TRANSBALTICA XI: Transportation Science and Technology: Proceedings of the International Conference TRANSBALTICA, May 2-3, 2019, Vilnius, Lithuania ... Transportation and Infrastructure) 3030386651, 9783030386658

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Lecture Notes in Intelligent Transportation and Infrastructure Series Editor: Janusz Kacprzyk

Kasthurirangan Gopalakrishnan Olegas Prentkovskis Irina Jackiva Raimundas Junevičius Editors

TRANSBALTICA XI: Transportation Science and Technology Proceedings of the International Conference TRANSBALTICA, May 2–3, 2019, Vilnius, Lithuania

Lecture Notes in Intelligent Transportation and Infrastructure Series Editor Janusz Kacprzyk, Systems Research Institute, Polish Academy of Sciences, Warszawa, Poland

The series “Lecture Notes in Intelligent Transportation and Infrastructure” (LNITI) publishes new developments and advances in the various areas of intelligent transportation and infrastructure. The intent is to cover the theory, applications, and perspectives on the state-of-the-art and future developments relevant to topics such as intelligent transportation systems, smart mobility, urban logistics, smart grids, critical infrastructure, smart architecture, smart citizens, intelligent governance, smart architecture and construction design, as well as green and sustainable urban structures. The series contains monographs, conference proceedings, edited volumes, lecture notes and textbooks. Of particular value to both the contributors and the readership are the short publication timeframe and the world-wide distribution, which enable wide and rapid dissemination of high-quality research output.

More information about this series at http://www.springer.com/series/15991

Kasthurirangan Gopalakrishnan Olegas Prentkovskis Irina Jackiva Raimundas Junevičius •

•

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Editors

TRANSBALTICA XI: Transportation Science and Technology Proceedings of the International Conference TRANSBALTICA, May 2–3, 2019, Vilnius, Lithuania

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Editors Kasthurirangan Gopalakrishnan SRM University-AP Amaravati, India Iowa State University Ames, IA, USA Irina Jackiva Transport and Telecommunication Institute Riga, Latvia

Olegas Prentkovskis Vilnius Gediminas Technical University Vilnius, Lithuania Raimundas Junevičius Vilnius Gediminas Technical University Vilnius, Lithuania

ISSN 2523-3440 ISSN 2523-3459 (electronic) Lecture Notes in Intelligent Transportation and Infrastructure ISBN 978-3-030-38665-8 ISBN 978-3-030-38666-5 (eBook) https://doi.org/10.1007/978-3-030-38666-5 © Springer Nature Switzerland AG 2020, corrected publication 2020 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Preface

International Scientific Conference “Transbaltica: Transportation Science and Technology” is a continuing traditional event of the Faculty of Transport Engineering at Vilnius Gediminas Technical University and is organized in cooperation with partners since 2001 for every two years. The 11th Transbaltica Conference took place on 2–3 May 2019 in Lithuania. Authors from 33 countries presented their researches and covered wide areas of scientific problems in the field of transport engineering, transportation and logistics, and interdisciplinary sciences related to transport. This proceedings represents the conference topics: Topics related to Transport Infrastructure cover research areas related to transport system elements, its lifetime and the integration of different transport modes. Research in the field of Transport Safety present various solutions for the safety of roads, airports and railway transport. Presentations in the area of Environment-Friendly Technologies cover such topic like engine technologies and a new type of fuel mixtures usage in transport means. Research papers in the field of Traffic Modelling and Control presents the results of city transport problem solutions such as traffic congestions and emission reduction or integration of different transport modes. Research papers related to the topic of Railway Systems present various solutions in the area of wear reduction of wheel and track, vehicle dynamics, vibration and other scientific problems. Similarly, Vehicle Engineering cover related problems in areas like hydrodynamics, engine technologies, durability or drive train system research. Logistics and Multimodal Transport papers present the organization of transport flows, freight and passenger mobility, environmental impact, operations at transport and logistics companies, issues of safety and security, new circumstances affecting the carriage of goods and passengers. Presentations, related to Autonomous Solutions together with the usage of new sources of energy for transport in the cities, present the importance of making timely decisions and selecting the proper city transport modes. The program committee of the 11th International Scientific Conference “Transbaltica: Transportation Science and Technology”, the organizers and the editors of the proceedings would like to acknowledge the participation of all v

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Preface

reviewers who helped to refine the contents of this volume and evaluated conference submissions. Our thanks go to all members of the program committee: • Dr. Kasthurirangan Gopalakrishnan, Iowa State University, USA—Chairman • Prof. Olegas Prentkovskis, Vilnius Gediminas Technical University, Lithuania— Co-Chairman • Dr. Vidas Žuraulis, Vilnius Gediminas Technical University, Lithuania— Co-Chairman • Dr. Raimundas Junevičius, Vilnius Gediminas Technical University, Lithuania— Secretary • Daina Rinkevičienė, Vilnius Gediminas Technical University, Lithuania— Co-Secretary • Prof. Aleksander Sladkowski, Silesian University of Technology, Poland • Prof. Andrii Bieliatynskyi, National Aviation University, Ukraine • Prof. Christos Pyrgidis, Aristotle University of Thessaloniki, Greece • Prof. Gianluca Dell’Acqua, University of Naples Federico II, Italy • Prof. Gintautas Bureika, Vilnius Gediminas Technical University, Lithuania • Prof. Irina Yatskiv (Jackiva), Transport and Telecommunication Institute, Latvia • Prof. Marijonas Bogdevičius, Vilnius Gediminas Technical University, Lithuania • Prof. Nijolė Batarlienė, Vilnius Gediminas Technical University, Lithuania • Prof. Pavlo Maruschak, Ternopil Ivan Pul’uj National Technical University, Ukraine • Prof. Rafal Burdzik, Silesian University of Technology, Poland • Prof. Sergejus Lebedevas, Klaipėda University, Lithuania • Prof. Zdenek Dvorak, University of Žilina, Slovakia • Prof. Edgar Sokolovskij, Vilnius Gediminas Technical University, Lithuania • Dr. Artem Bezuglyi, State Road Research Institute Named M.P. Shulgina, Ukraine • Dr. Dalibor Barta, University of Žilina, Slovakia • Dr. Jadranka Jovič, University of Belgrade, Serbia • Dr. Jonas Matijošius, Vilnius Gediminas Technical University, Lithuania • Dr. Juris Smirnovs, Riga Technical University, Latvia • Dr. Katerina Krayushkina, State Road Research Institute Named M.P. Shulgina, Ukraine • Dr. Kristina Čižiūnienė, Vilnius Gediminas Technical University, Lithuania • Dr. Laima Miliauskaitė, Vilnius Gediminas Technical University, Lithuania • Dr. Rolandas Makaras, Kaunas University of Technology, Lithuania • Dr. Viktor Skrickij, Vilnius Gediminas Technical University, Lithuania • Dr. Virgilija Vasilienė-Vasiliauskienė, Vilnius Gediminas Technical University, Lithuania • Dr. Yonggang Wang, Chang’an University, China • Dr. Giedrius Garbinčius, Vilnius Gediminas Technical University, Lithuania

Preface

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• Dr. Algirdas Šakalys, East-West Transport Corridor Association, Lithuania • Vytenis Surblys, Vilnius Gediminas Technical University, Lithuania Thanking all the authors who have chosen “Transbaltica: Transportation Science and Technology” as the publication platform for their research, and we would like to express our hope that their papers will help in further developments in design and analysis of complex systems, offering a valuable and timely resource for scientists, researchers, practitioners and students who work in these areas. Kasthurirangan Gopalakrishnan Olegas Prentkovskis Irina Jackiva Raimundas Junevičius

Contents

The Survey of Transport Vehicle Delays at the Traffic Light Intersections of the Urban Arterial Streets . . . . . . . . . . . . . . . . . . . . . . . Oleksandr Stepanchuk, Andriy Belyatynskyi, and Olexander Pylypenko

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Supporting of Ecological Safety of Run-off from the Territory of Objects of Road Infrastructure, Contaminated by Petroleum Products . . . . . . . . . . . . . . . . . . . . . . . . . . Valentina Iurchenko, Oxana Melnikova, Larysa Mykhailova, Elena Lebedeva, and Nikolay Mikhalevich

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Comparison of FRAM and CPN Approaches for Analysis of Incidents in Aerodrome Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Paulina Rutkowska, Malwina Okulicz, and Jacek Skorupski

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Influence of the Information Disruptions in A-CDM System on the Time of Readiness for Take-off . . . . . . . . . . . . . . . . . . . . . . . . . . Malwina Okulicz, Paulina Rutkowska, and Jacek Skorupski

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Degradation of Transport Infrastructure Under Breach of Drainage: Strain and Corrosion Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pavlo Maruschak, Andriy Sorochak, Denys Baran, and Olegas Prentkovskis Images of Vibrations of a Passing Railway Vehicle . . . . . . . . . . . . . . . . Rafał Burdzik and Paweł Słowiński

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Application of Modern Monitoring Measures in Lithuanian Dangerous Cargo Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Erikas Mazėtis and Nijolė Batarlienė

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User Acceptance of Driverless Public Transportation: A Questionnaire-Based Study in Budapest . . . . . . . . . . . . . . . . . . . . . . . Mohammad Maghrour Zefreh and Adam Torok

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Assessment of Crash Risks at Highway Access Points with Restricted Sight Visibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sujata Basu and Pritam Saha

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Basic Methods to Support City Bus Fleet Conversion Towards a 100% Electric Bus Fleet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Krzysztof Krawiec

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Analysis of Pedestrian Movements on Sidewalks: A Case Study in Kolkata, India . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Deotima Mukherjee, Soumyadip Das, Pritam Saha, and Sudip K. Roy

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Simulation Processes of Construction of Optimal Routes for the Delivery of Goods by Road Transport on Urban Road Network in Mountainous Cities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Viktor Danchuk, Talal Ameen, Olena Bakulich, and Vitaliy Svatko Analysis of Quality of Car Rental Services Following Example of “Citybee” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Kristina Čižiūnienė and Rolandas Vitkūnas Assessment of the Interoperability of Railway and Maritime Transport in Lithuania . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 Aldona Jarašūnienė, Vladislav Lagunovič, and Kristina Čižiūnienė Modernizing of the Rail Transport Curriculum and Study Process . . . . 139 Enno Lend and Wladimir Segercrantz Comparison of Studies of Dangerous Cargo Flow Distribution Between Rail and Road Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 Gediminas Vaičiūnas, Olha Porkuian, and Jelena Nozhenko Applying the Business Model Canvas to Increase Enterprise Competitiveness: A Case Study of Transport Company . . . . . . . . . . . . . 158 Virgilija Vasilienė-Vasiliauskienė, Aidas Vasilis Vasiliauskas, Monika Donculaitė, and Ieva Meidutė-Kavaliauskienė Comparison of Railway Routes Enabling Freight Transportation from the Eastern Border of Poland to the West . . . . . . . . . . . . . . . . . . . 171 Wojciech Kamiński and Aleksander Sładkowski The Impact of the Bioethanol Fuel on the Exhaust Gas Emission of a Two-Stroke Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Keio Küüt, Risto Ilves, Arne Küüt, and Jüri Olt Research of Mathematical Model of Movement of Six-Axle Locomotives with Controllable Wheelsets Installation . . . . . . . . . . . . . . 193 Serhii Kliuiev, Dmytro Bobyr, Gediminas Vaičiūnas, and Stasys Steišūnas

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Arrangement of the Continuous Welded Rail on the Curved Tracks of Short Radius . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 Volodymyr Tverdomed, Viktor Tkachenko, Svitlana Sapronova, Oleksandr Aharkov, and Liudmyla Drahiieva Modeling of Management Strategies for Manufacturing Technological Processes in Metro Power Supply Projects . . . . . . . . . . . . . . . . . . . . . . . 211 Ivan Kulbovskyi, Halyna Holub, Svitlana Sapronova, Viktor Tkachenko, and Marina Musorina Improving the Dynamics of Bogies of Railway Freight Cars by the Spring Suspension Enhancement . . . . . . . . . . . . . . . . . . . . . . . . . 220 Mykola Gorbunov, Serhii Kara, Olegas Lunys, and Gediminas Vaičiūnas The Strength Simulation of a Predeformed Design of a Hatch Cover of Open Car . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Oleksij Fomin, Nikolai Gorbunov, Alyona Lovska, and Yuliia Fomina Study of Dynamic Loads in the Wheel and Rail Contact Influence on the Maximum Adhesion Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . 235 Nikolai Gorbunov, Gintautas Bureika, Maksim Kovtanets, Gediminas Vaičiūnas, Olga Prosvirova, and Oksana Sergienko The New Simulation Approach to Tramway Safety Against Derailment Evaluation in Term of Vehicle Dynamics . . . . . . . . . . . . . . . 245 Dariusz Kalinowski, Tomasz Szolc, and Robert Konowrocki Modeling of Hybrid Autonomous Vehicle Fuel Consumption . . . . . . . . . 255 Imre Zsombók and Máté Zöldy Justification of Influence of the Form of Nozzle and Active Surface of Bernoulli Gripping Devices on Its Operational Characteristics . . . . . 263 Volodymyr Savkiv, Roman Mykhailyshyn, Frantisek Duchon, and Pavlo Maruschak Evaluation of Intelligent Transportation System in Security Consideration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 Hakan Basargan, Szalay Zsolt, and Árpád Török Application of New Materials During Rehabilitation of Road Structures Using Cold Recycling Technology . . . . . . . . . . . . . . . . . . . . . 283 Kateryna Krayushkina, Tetiana Khimeryk, Olena Oliynyk, Liliia Gnatiuk, and Hanna Novik Research of Dynamic Processes of the System “Track – Vehicle”, When Wheel Is with 0.7 mm Metal Scale . . . . . . . . . . . . . . . . . . . . . . . . 290 Marijonas Bogdevičius and Rasa Žygienė

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Dynamic Charging of Electric Buses as a Way to Reduce Investment Risks of Urban Transport System Electrification . . . . . . . . . . . . . . . . . . 297 Mikołaj Bartłomiejczyk and Marcin Połom Multibody Simulation of Rail Vehicle Running Considering Track Flexibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 Ján Dižo, Miroslav Blatnický, and Stasys Steišūnas Preparation of Parametric Model of Underground Metro Door Force Acting on Coarse Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 Miroslav Blatnický, Ján Dižo, and Gediminas Vaičiūnas Investigation of Hydrodynamic Processes in the System – “Pipeline-Fittings” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331 Mykola Karpenko and Marijonas Bogdevičius Innovative Technical Solutions to Improve the Cooling Efficiency of Friction Brake Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341 Juraj Gerlici, Kateryna Kravchenko, Vladimir Hauser, Mykola Gorbunov, Tomas Lack, and Valentin Mogila Research on the Rotation Vibration in the Transmission with Gear Box Defects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350 Paulius Bogdevičius, Marijonas Bogdevičius, and Olegas Prentkovskis Application of Virtual Prototype to Heavy-Duty Gearbox Housing Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361 Kamil Rehak, Pavel Kucera, and Ales Prokop Modeling of Diesel Engine Energy Efficiency Parameters and Evaluation of Different Combustion Models . . . . . . . . . . . . . . . . . . 369 Linas Jonika, Sergėjus Lebedevas, and Vygintas Daukšys On the Issue of Wheel Flange Sliding Along the Rail . . . . . . . . . . . . . . . 377 Evgeny Mikhailov, Stanislav Semenov, Svitlana Sapronova, and Viktor Tkachenko Ensuring the Cycling Safety by Improving Bicycle Infrastructure . . . . . 386 Irina Makarova, Aleksey Boyko, Ksenia Shubenkova, and Anton Pashkevich Climatic Chamber Testing of Innovative Brake System for Rolling Stock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397 Tasko Smileski and Gligorche Vrtanoski Adapting a One-Dimensional Mathematical Model to the Dual Fuel Engine In-Cylinder Processes Modelling . . . . . . . . . . . . . . . . . . . . . . . . 407 Sergėjus Lebedevas, Vygintas Daukšys, and Linas Jonika

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Building on a Traffic Code Violating Monitor for Autonomous Vehicles: Trio Overtaking Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415 Dan M. Costescu Evaluation of Sustainability of the Transport System of Urbanized Areas Considering the Development of Bicycle Transport . . . . . . . . . . . 427 Irina Makarova, Vadim Mavrin, Kirill Magdin, Ksenia Shubenkova, and Aleksey Boyko Planning Method for the Maintenance and Repair of the Vehicle Fleet Based on the Life Cycle Contract . . . . . . . . . . . . . . . . . . . . . . . . . 434 Irina Makarova, Eduard Mukhametdinov, Larisa Gabsalikhova, Anton Pashkevich, and Ilsur Giniyatullin Simplified Mathematical Model of Changes in Sound Power Level Caused by the Perpendicular Forces that Arise When the Rail Contacts the Wheel with Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445 Viačeslav Petrenko and Vladas Kukėnas The Challenges and Opportunities for Road Freight Transport . . . . . . . 455 Edvardas Liachovičius and Viktor Skrickij Organization of Damaged Road Rehabilitation in the Village of Rybany . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 466 Peter Durech and Zdenek Dvorak Criticality Assessment of Railway Bridges . . . . . . . . . . . . . . . . . . . . . . . 474 Zdenek Dvorak, Maria Luskova, David Rehak, and Simona Slivkova Energy and Ecological CI Engine Indicators Having Replaced Diesel with Chicken Fat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 484 Alfredas Rimkus, Tadas Vipartas, Jonas Matijošius, Saulius Stravinskas, and Oleksandra Shepel Improvement of Fuel Economy and Starting Properties of the Diesel Engine by Heating the Air at the Inlet . . . . . . . . . . . . . . . . 494 Mykola Dmytrychenko, Yurii Gutarevych, Yevhenii Shuba, Oleksandr Syrota, Dmitrij Trifonov, and Jonas Matijošius Analysis of Operational Characteristics of Pneumatic Device of Industrial Robot for Gripping and Control of Parameters of Objects of Manipulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504 Volodymyr Savkiv, Roman Mykhailyshyn, Frantisek Duchon, Olegas Prentkovskis, Pavlo Maruschak, and Illia Diahovchenko Riga International Coach Terminal: Safety and Security Risk-Based Decision-Making Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 511 Vaira Gromule and Irina Yatskiv (Jackiva)

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Use of Container and Piggyback Services in International Railway Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521 Mykola Kurhan, Laura Černiauskaitė, and Dmytro Kurhan Influence of Parameters of Electric Locomotive on its Critical Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 531 Irina Klimenko, Jan Kalivoda, and Larysa Neduzha The Environment of Extremist Textual Content Threatening Transportation Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 541 Olga Zervina Decision-Support Framework for the Urban Public Transport System Sustainable Planning: Riga Case Study . . . . . . . . . . . . . . . . . . . . . . . . . 552 Irina Yatskiv (Jackiva) and Evelina Budilovich (Budiloviča) Study of Field Testing on Car Body Vibrations of Moving Passenger Car with Wheel Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562 Stasys Steišūnas, Gintautas Bureika, Olha Porkuian, and Volodymyr Nozhenko About Physical Aspects of Increasing Durability of Aluminum Alloys Due to Impact-Oscillatory Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572 Mykola Chausov, Pavlo Maruschak, Elena Zasimchuk, Andrii Pypypenko, Roman Bishchak, and Iurii Burda Special Aspects of Determining the Dynamic Load of the Tank Container During Its Transportation in an Integrated Train Set by a Railway Ferry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 581 Alyona Lovska, Juraj Gerlici, Oleksij Fomin, Kateryna Kravchenko, Yuliia Fomina, and Tomas Lack Analysis of the Combustion Process of a Compression Ignition Engine Running on Diesel and Natural Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . 591 Saulius Stravinskas, Alfredas Rimkus, and Donatas Kriaučiūnas Anti-wear Properties of Jet Fuel with Camelina Oils Bio-Additives . . . . 601 Anna Yakovlieva, Igor Trofimov, Sergii Boichenko, Hubert Kuszewski, and Kazimierz Lejda The Model for Evaluating Criteria Describing the Internal Safety of a Railway Trip by International Train . . . . . . . . . . . . . . . . . . . . . . . 610 Lijana Maskeliūnaitė and Henrikas Sivilevičius Analysis of Existing Train Lines and International Railway Transport Corridors of Ukraine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622 Evgeniya Ugnenko, Anna Shevchenko, Oleksander Matviienko, Anatoliy Maliavin, Gintas Viselga, and Vytautas Turla

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Control Technology of Railway Traffic Safety: A System Approach and Digitalization . . . . . . . . . . . . . . . . . . . . . . . . . . 633 Valerii Samsonkin and Oleksii Goretskyi Correction to: About Physical Aspects of Increasing Durability of Aluminum Alloys Due to Impact-Oscillatory Loading . . . . . . . . . . . . Mykola Chausov, Pavlo Maruschak, Elena Zasimchuk, Andrii Pypypenko, Roman Bishchak, and Iurii Burda

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Author Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639

The Survey of Transport Vehicle Delays at the Traffic Light Intersections of the Urban Arterial Streets Oleksandr Stepanchuk(&), Andriy Belyatynskyi, and Olexander Pylypenko National Aviation University, Kiev 03058, Ukraine [email protected]

Abstract. The survey of traffic light intersections of the Kyiv street network has been analyzed. The certain regularities leading to the delays and traffic difficulties were revealed in results obtained. Keywords: Traffic light intersections length


Average delay of vehicles
Queue

1 Actuality of the Subject Matter The interrelation between vehicular and pedestrian traffic in conditions of significant number of traffic light intersections along the urban arterial roads has the certain characteristic regularities, especially in the intersection zones. Such problem has been extensively studied in many scientific papers for uncontrolled intersections mainly, where the transport flow models have been developed and techniques to obtain necessary accurate data have been proposed. But for signalized intersections such type exact results are very difficult to obtain [1, 2]. One of the reasons of such situation is that any vehicular traffic cannot be considered as a stationary process, since it is subjected to periodic changes determined by the length of traffic signal cycle.

2 Problem Solution The other reason is that the transport vehicle approaching along arterial road to traffic light intersection is under the significant influence of the upstream traffic light intersections where traffic flows are formed mainly as some compact groups of vehicles called “platoons”. In such conditions, the traffic light intersections even under the perfect traffic light control leads to traffic flow instability such as deceleration, braking, acceleration, stopping, and stopped delay of vehicles. The delay under the traffic light control occurs when that vehicles arriving to the intersection during red indication must wait the green indication to continue moving. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 1–9, 2020. https://doi.org/10.1007/978-3-030-38666-5_1

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O. Stepanchuk et al.

It should be noted also that the delay at the traffic light intersection within its single cycle consists of two components: the delay during the red phase and the delay during the green phase until the vehicle as a platoon’s member starts moving. Delay of transport vehicle at the traffic light intersection is one of the generally accepted in the world practice functional criteria for assessment of traffic management and traffic control levels. The purpose of traffic management and traffic control is to minimize the delays and maximize the traffic lanes capacity, accordingly. The studies described in [3] confirm that a single vehicle’s delay depends on the red phase length, approach time and queue move-up time. The average delay of vehicles at the signalized intersection depends on the following factors: the length of traffic light cycle, the effective green time, the rate at which the vehicles approach the intersection, the rate at which vehicles in a queue start moving up from the intersection at the green phase, the number of vehicles gathered in a queue before the red phase of the light for drivers occurs. Nowadays there are a number of known methods (Bekmen, Webster, Newell, McNeill and others) to determine the transport delays at the signalized intersections of different types. It should be noted that the authors of these papers have made a significant contribution to world science dealing with development and improvement of delay determination models; these models can be used to determine the average delay at a certain signalized intersections and they should be used to implement traffic lights at the intersections and automated traffic control systems. The objective of our study was to assess how the signalized intersections influence the traffic speed. The study was conducted in three stages: – determination of the number of forced stops as a consequence of vehicle arrival during the red interval of traffic light; – determination of the average delay time of vehicle at the signalized intersections where queues do not occur (there is a free mode of traffic); – determination of the average delay time of vehicle at the signalized intersections where queues has been formed and exists during a long time. The 568 traffic lights are located on the Kyiv highways network. Therefore, any vehicle route along the Kyiv street network includes, on average, about 10 traffic light intersections. Nowadays, there are different methods of coordinated traffic control on the street network of cities, like green wave, but forced stop of vehicles caused by red signal of traffic light will always be observed. The question naturally arises, how often any vehicle will need to stop at the red signal of the traffic light and how many intersections it will drive without stops. To answer this question, it was conducted the survey aimed to determine the number of forced stops of vehicles caused by red signal of traffic light with respect to the total number of traffic lights located along the same traffic route. The survey was conducted on the Kyiv street network during 2012–2017. This survey’s results are represented on Fig. 1. The correlation coefficient is: r = 0.917.

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3

By the value of the correlation coefficient, it can be concluded that strong connection exists between the number of traffic lights along the vehicle’s traffic route and the number of forced stops caused by the red signal of traffic light.

Fig. 1. The correlation field of the number of traffic lights along the traffic routes to the forced stops at them.

Based on the obtained result and the performed correlation analysis, it was built the regression model of dependence between the number of traffic lights located along the traffic route and the number of forced stops caused by the red signal of the traffic light. The regression equation has the form: y ¼ 0:3285x þ 0:054:

ð1Þ

The determination coefficient: R2 = 0.845. The objective of the second stage of the study was to determine the average delay of vehicles at a signalized intersection, which allows determining some optimal extra time necessary to drive through signalized intersections under any traffic conditions. Regulatory criteria are the average delay and the queue length that occurs at the intersection. Minimization of these two criteria is achieved at the minimum values of the cycle time that are possible under certain traffic conditions. To determine the delay time of vehicles at the signalized intersection, we use the well-known technique [3], which allows us to determine the average delay, saturation flow and the intersection efficiency rate. 25 signalized intersection along the Kyiv arterial streets were selected for this survey. All necessary indicators were taken along the most loaded traffic route and each intersection was observed during twenty cycles of traffic lights operation [4]. By analysis of the survey results it was concluded the following: – the average delay per vehicle at signalized intersection is 28.3 s that involves two components: the average stopped delay (25.4 s) caused by arrival of vehicle during the red interval of traffic light and queue move-up time (2.9 s) taken during the green interval when the queue of vehicles that had formed during the previous red

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interval has not yet fully dissipated. It should also be noted that the average number of vehicles stopped at the intersection was 12, while those that drove the intersection without stopping was 16; – the average efficiency rate of signalized intersection is 0.57. But it should be noted that this rate varies significantly at the different intersections, namely: on the arterial roads functioning according to traffic control system’s strategy “green wave”, it ranges within 0.75–0.80 on average while on collector roads and even arterial roads without “green wave” control strategy it ranges only within 0.15–0.20. It is also necessary to note that according to the data obtained during the survey, the great correlation (r = 0.945) was found between the red interval of traffic light and the average delay per vehicle at the intersection at the red signal of the traffic light (see Fig. 2). By the results of the correlation analysis, the regression model of the dependence between the red interval of traffic light and the average delay per vehicle at the intersection has been deduced: y ¼ 0:602x þ 1:47:

ð2Þ

The determination coefficient R2 = 0.892.

Fig. 2. The correlation field of the red interval of traffic lights.

The analysis of the observation results argues that the presence of traffic lights on the city’s street network leads to inevitable time delays. To study the causes of queue formation at the traffic light intersections along the arterial streets of the Kyiv city, there were used only the intersections where the queues were observed during the whole day. The results of this survey were processed according to the technique [5]. In our case, as an example, for a more detailed analysis of queue formation at traffic light intersections, let’s consider the intersection of the O. Teliga and O. Olzhich streets. This intersection is located on the main city street.

Number of vehicles driven through the intersection, units

– 948 1,120 1,125 1,116 1,133 1,174 1,120 1,100 1,026 1,003

Number of vehicles arrived at the intersection, units

– 948 1,216 1,289 1,254 1,163 1,120 1,094 1,029 930 897

The completion time of observation

7:01 7:30 7:59 8:28 8:57 9:26 9:55 10:24 10:53 11:22 11:51

– 0 96 164 138 30 −54 −26 −71 −96 −106

The number of vehicles that haven’t driven through the intersection during the period, units

The number of vehicles that haven’t driven through the intersection per cycle, units – 0 8.00 13.67 11.50 2.50 −4.50 −2.17 −5.92 −8.00 −8.83 – 0 96 260 398 428 374 348 277 181 75

Number of vehicles in queue, units

– 1.32 1.11 1.11 1.12 1.10 1.06 1.11 1.13 1.22 1.24

Time interval between vehicles, sec

– 0.00 8.91 15.16 12.86 2.75 −4.78 −2.41 −6.71 −9.73 −10.99

Delay time per period, sec.

– 0.000 0.055 0.094 0.079 0.017 −0.031 −0.015 −0.041 −0.055 −0.061

The queue increase rate, vehicles/sec

Table 1. The main characteristics of queue formation at the intersection according to observation data.

– 0 336 910 1,393 1,498 1,309 1,218 969.5 633.5 262.5

Queue length, m

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The initial data for this intersection consist of the following information: the T intersection, having six lanes on the Olena Teliga street and two lanes on the Oleg Olzhich street; traffic light cycle is Tc = 145 s with two phase traffic signal operation; the green interval tgreen = 105 s; red interval tred = 34 s; amber interval tamber = 6 s. The distance between vehicles in the queue along the same lane is accepted 2 m; the estimated vehicle length is 5 m; driver reaction time tr = 1 s. To simplify necessary calculations, the total observation time was divided into certain periods of 12 traffic light cycle (29 min) long each, so the number of vehicles arriving at the intersection was quantified during precisely these time periods, that is, within 29 min each. To ease the calculations all survey results are formed in the Table 1. The first lane of the carriage way was excluded from the calculation for it is assigned for public transport only. The number of vehicles that haven’t driven through the intersection at the end of each period was defined as the difference between the number of vehicles arrived at the intersection during the specified period and the number of vehicles driven through the intersection during the same period. The number of vehicles that haven’t driven through the intersection per cycle is defined as the difference between the number of vehicles arrived at the intersection during a specified period and the number of vehicles driven through the intersection for the same period, then dividing the obtained value by the number of traffic light cycles during the same survey period. The queue length Lqueue at the end of each 12-th cycle was defined as the product of the number of vehicles that haven’t driven through the intersection for the current period and the vehicle length, taking into account the distance between vehicles (7 m). Based on the calculations performed it was found that the maximum quantity of the vehicles arrived at the intersection was at 8:28 and amounts to 1,289 units (0.741 vehicles/sec), which is on 278 units (0.066 vehicles/sec) more than the maximum traffic lane capacity (see Fig. 3). With time, the intensity decreases somewhat and at 9:26, it becomes almost equal to the intersection traffic capacity (Nmax). It is during this period that queue reaches its maximum of 428 units. As the traffic intensity decreases and became lower than the intersection traffic capacity, the queue begins to reduce. Graphically, one can estimate the time period during which the queue fades away. In this case such period is about two hours – from 9:55 to 11:51 (see Fig. 4).

Fig. 3. Arrival of vehicles at the intersection during the observation period.

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Fig. 4. The number of vehicles in the queue in front of the traffic light.

The crucial factors of the queue formation are the number of vehicles that haven’t driven through the intersection during every traffic light cycle, and the time period during which such problem takes place. In this observation, the maximum number of vehicles that had no time to drive through the intersection during one traffic lights cycle, was 14 units, and as such period of intersection overload lasted for a considerable time, so the total length of the queue had increased up to 1,498 m. Thus, the traffic delay at the intersection occurs because number of vehicles arriving at the intersection exceeds its traffic capacity on average 9.4%. In this case, to eliminate the queue of 1,498 m long completely it is necessary 7.7 min even at the condition when another vehicles do not arrive at the intersection at all (see Fig. 5).

Fig. 5. The number of vehicles in the queue and time of its fading away.

The curve on Fig. 5 was approximated by cubic parabola: y ¼ 0:6921x3  30:28x2 þ 267:1x  268:97: The determination coefficient R2 = 0.9636.

ð3Þ

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How to solve such type problems was one of the tasks of this survey. In the other words, how much time the transport vehicle requires to overcome the queue at the traffic lights intersection when its traffic capacity doesn’t meet the traffic needs and certain traffic congestion has been formed at this intersection already. In this way, there were analyzed all data characterizing the time necessary to overcome the queue depending on its length. By the results of this analysis, it was found that correlation is observed between the time taken to arrive at the waiting queue (traffic congestion) at the traffic light intersection and the queue length (see Fig. 6).

Fig. 6. Dependence between the time required by vehicles queue to travel through the intersection and the queue length.

The correlation coefficient r = 0.976. The regression equation: y ¼ 0:241x þ 14:8:

ð4Þ

The determination coefficient R2 = 0.954.

3 Conclusions This approach is very important for creating an efficient traffic flow management system because the main the task of traffic flows management is to minimize the probability of traffic congestion formation at the intersections of urban arterial streets having the “saturated” traffic flow. The purpose of the traffic flow management system is to prevent traffic congestion and, whenever the congestion occurs, to provide possible alternative routes that will enable to redistribute the flows and minimize the time losses because all this are required to determine the effective traffic routes of vehicles. Hence, by applying the approaches analyzing above to the system of monitoring and management of traffic flows, it can be determined the expected number of vehicles at the intersections at rush hours and made timely decisions on their redistribution between parallel streets, which, in turn, minimizes the time of traffic delays throughout the city street network.

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References 1. Hayмoвa, H.: Teopeтичecкиe ocнoвы и мeтoды yпpaвлeния тpaнcпopтными пoтoкaми cpeдcтвaми мeзocкoпичecкoгo мoдeлиpoвaния, 331 (2015) 2. Stepanchuk, O.: Surveying of Traffic Congestions on Arterial Roads of Kyiv City/O. Stepanchuk, A. Bieliatynskyi, O. Pylypenko, S. Stepanchuk/ Procedia Engineering. 187, pp. 14–21 (2017) 3. Meтcoн, T., Cмит, У., Xapд, Ф.: Opгaнизaция движeния, 464 (1960) 4. Peйцeн, Є.: Opгaнiзaцiя i бeзпeкa мicькoгo pyxy, 454, Київ (2014) 5. Бaxтинa, O.: Paзpaбoткa мeтoдoв pacчeтa и oцeнки зaтopoвыx cocтoяний тpaнcпopтнoгo пoтoкa нa yличнo-дopoжнoй ceти гopoдoв (нa пpимepe г. Кpacнoдapa) (2006)

Supporting of Ecological Safety of Run-off from the Territory of Objects of Road Infrastructure, Contaminated by Petroleum Products Valentina Iurchenko1(&), Oxana Melnikova1, Larysa Mykhailova2, Elena Lebedeva1, and Nikolay Mikhalevich3 1

Kharkiv National University of Civil Engineering and Architecture, Sumskaya 40 str., Kharkiv, Ukraine [email protected], [email protected], [email protected] 2 Brandenburg University of Technology at Cottbus, Konrad-Wachsmann-Allee 6, Cottbus, Germany [email protected] 3 Kharkiv National Automobile and Highway University, Petrovskoho 26 str., Kharkiv, Ukraine [email protected]

Abstract. In the experimental studies it was found that open run-off settling in comparison with the close settling systems improves the effect of PP disposal by 1.3 times, hexane fraction of PP – nearby 2 times, separate alkanes C22–C27 – by 2–3 times. Duration of open settling of run-off, formed in the territory of suburban parking areas, shall be 3–10 days. The effect of run-off purification from PP under sedimentation is mainly conditioned by disposing of fraction of nominally complex PP. Keywords: Suburban road infrastructure facilities
Run-Off treatment from petroleum products
Petroleum products fractionation
Settling parameters of Run-Off
Mathematical description

1 Introduction Transport is a required condition of operation of the industrial society. As the result, the essential problem is ecological safety of operation of motor roads and objects of road infrastructure (ORI), such as fuel filling stations, parking areas, tire fitting centers, service stations, car wash and others, providing great man-made impact on natural ecosystems due to strong emission of ingredient and parametric contamination [1, 2]. In regards to rate of excess of MPC for water and soil ecosystems in the territories, boarded on the objects of motor roads, the biggest ecological hazard is petroleum products (PP) [2–4] – hydrocarbon mixture and their derivatives [5, 6]. The main petroliferous environs, generated by ORI, are exhaust gases of cars and run-off – wash-off from road way and territories of ORI [7, 8]. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 10–17, 2020. https://doi.org/10.1007/978-3-030-38666-5_2

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For the protection of soil and water ecosystems in the territories, boarded on ORI, from ecologically hazardous run-off, formed in these objects, it is necessary to produce effective engineering system for collecting, disposing and treatment of these sewages. Specifically such requirement is relevant to suburban ORI, located in the territories without centralized sewage facilities. In CIS and foreign countries it is recommended to use mechanical purification facilities of both open and close types for clearing of washoff from the surface of motor roads and bridge works [9]. However, the proposed facilities have not achieved large-scale implementation in Ukraine (particularly on the suburban objects) because of the range of technologic, operating and economic problems. Based on local and international experience in clearing of run-off [7, 10], formed on ORI, economic parameters of construction and operation of purification facilities, the mechanical method of clearing of run-off by means of settling is the advanced method for implementation on suburban ORI. The work goal is evaluation of efficiency of clearing of run-off, formed on ORI from various fractions of PP under settling and impact of process parameters on it. Research objectives: 1. Experimental study of the effectiveness of the treatment of surface wastewater generated in the suburban ORI from PP during settling. 2. Identification of hydrocarbons in flushes from the ORI territories before and after cleaning by settling. 3. Modeling the dependence of the purification effect of run-off from the ORI territories on the sedimentation parameters.

2 Objects and Research Methods The objects of the experimental researches are: – Run-off in winter season – snow cover, formed in the territories of suburban ORI; – Run-off in summer season – artificial wash-off from waterproof coating of traffic areas of suburban ORI. The snow samples were collected at 0.5 m from the edge line of traffic area of ORI on the 12th day after the snowfall. The samples of the run-off from ORI territories were obtained by wash-off method (the period without rains before sampling was 10–15 days). The wash-off was performed with cotton tampon in the definite volume of distilled water from the definite coat area, limited by the wooden grid [10]. In the experimental researches the processes, occurring under the settling of run-off in open and close tanks, were prototyped. The studied sewage water was placed into graduated glasses and settled within 130 days. For modeling of close settling system, the glasses were closed with plastic lids. The settling in winter period occurred in laboratory conditions at a temperature of 15 °C and air velocity 0 m/s, in summer period – 22–26 °C and air velocity 0.5–2 m/s. Water samples of supernatant liquid were collected with the probe, without damaging of settled sludge and surface film (in those variant, where it was formed).

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PP content in water environment (melted snow) was determined by gravimetric method [11]. From the water PP were extracted with chloroform, then the solvent was removed under vaporization, and the rest was dissolved in hexane and the polar compounds were separated on treatment on the column with aluminum oxide. The solvent was vaporized and the rest weight was gravimetrically measured [11]. During analysis performance PP extraction only with hexane usage was carried out at the same time [11]. It allowed to fractionate PP [12], contaminating run-off, by means of separating them into the fraction of nominally aliphatic PP – petrol, kerosene oil, diesel fuel (hexane extract), and the fraction of nominally complex PP – high-molecular and heterorganic (the difference between PP content, that are extracted with chloroform + hexane, and PP, that are extracted only with hexane). Identification and quantitative determination of the concentration of special saturated hydrocarbon, included in PP composition of studied water environment, were performed by means of the gas-liquid chromatography (chromatographer Fisons 8065, HT8 column), using the mass-spectrometer detector (Fisons MD800). Hewlett Packard standard alkanes Part. No. 18710-60170 was used for quantification and identification of general hydrocarbons and n-alkanes. The mathematical treatment of the experimental data, building of the surface areas were performed in software Microsoft Excel.

3 Results and Discussion Comparison of efficiency of PP disposing under open and close settling of run-off in winter season (the initial concentration of PP 82.4–186.5 mg/dm3) was performed after 30 days of exposition (see Table 1). The identification results of alkanes (extracted with hexane), which contaminate run-off, formed in the territory of suburban fuel filling stations, and alkanes, which contaminate the same run-off after close and open settling during 30 days, are presented in Fig. 1. Table 1. Average values of surface wastewater treatment, formed in the territories of out-oftown ORI, from PP after 30 days of sedimentation. Settling mode

The residual volume of sewage in relation to the initial, %

Efficiency of water purification (%) of PP Conditionally Conditionally aliphatic PP complex PP

Mass of remote PP, mg

Close settling Open settling

100

50.4

82.0

71.0

+91.1 (+31.4)*

92.1

70

44.2

53.3 75.7 (67.5)* (83.1)*

()* – taking into account the reduction of the volume of sewage

By theory in the simulated purification facilities reduction of PP content in the treated run-off occurred principally due to three processes: vaporization and spreading of fugitive PP; settling of suspended and emulsified PP independently or under adsorption on mineral suspended matters; oxidative destruction of PP.

Share in the sum of identified alkanes, %

Share in the sum of identified alkanes, %

Supporting of Ecological Safety of Run-off from the Territory of Objects 50 45 40 35 30 25 20 15 10 5 0

50 45 40 35 30 25 20 15 10 5 0

C20 C21 C22 C23 C24 C25 C26 C27 C28

C19 C20 C21 C22 C23 C24 C25 C26 C27 C28 C29 C30 C31

Alkanes

Alkanes

a) Share in the sum of identified alkanes, %

13

b)

50 45 40 35 30 25 20 15 10 5 0 C19 C20 C21 C22 C23 C24 C25 C26 C27 C28 C29 C30

Alkanes

c)

Fig. 1. Identification of alkanes in run-off of the winter season (snow) from the parking lot of trucks before and after clearing by sedimentation: (a) initial sample; (b) after closed settling; (c) after open settling.

After such long sedimentation in the open system the liquid volume decreased by 30–35% due to vaporization in different variants of the experiment. Consequently the purification measures in this variant of the experiments were corrected, considering decrease of the volume of the settled liquid. As it is seen from the data of Table 1, the purification efficiency of the run-off from PP in the open settling system significantly (by 1.3 times) exceeded this factor in the close settling system, specifically for hexane fraction of PP (almost by 2 times). After open settling the increase of the concentration of nominally complex fraction of PP, extracted with chloroform + hexane, is conditioned, it appears that, by enrichment of products oxidation of hydrocarbons in the environment – heterorganic compounds, not extracted with hexane. This hypothesis is confirmed by the data gas chromatography analysis. As it is seen from the data of Fig. 1, in crude sewage C22–C27 essentially prevailed among alkanes, that composed above 80% of identified. After the close settling the concentration ratio of alkanes in run-off marginally changed: alkanes C19, C21, C24–C26 prevailed, whose proportion composed almost 60% of identified, and the content of C22–C27, in comparison with crude sewage, decreased approximately by 38%. The concentration ratio of alkanes in run-off after open settling changed more fundamentally under intensive air exchange. In run-off among alkanes C19 prevails (above 47% of identified). The proportion of alkanes C22–C27 is substantially lower than the proportion C19, and their concentration in comparison with crude sewage decreases by 2–3 times.

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Effect of purification, %

Consequently, open settling of run-off, that provides active air exchange, facilitating vaporization and spreading of fugitive PP, and also oxygen supply oxidative destruction of PP with microorganisms, is preferable for purification of run-off from PP, formed in the suburban ORI. It is found that settling time shall not exceed 7–10 days (particularly in summer season), as under the further settling the thick biofilm appears on the surface of the settled liquid, that prevents free airing and creates conditions for close settling, that has a negative impact on efficiency of purification from PP [2, 13]. The dynamics of purification efficiency of run-off from PP, formed in the suburban parking areas, under open settling, is presented in Fig. 2. As it is seen, on the 3rd day of surface sewage water settling the effects of purification from PP in the samples practically became stable (75–80%). In the process of sedimentation not only general content of PP, but also the fraction ratio of PP nominally aliphatic and complex changed in treated sewage water. 100 80 60 40 20 0 0

2

4

6

8

10

12

Time of settling, day Parking №1

Parking №2

Fig. 2. Efficiency of purification of surface wastewater generated in the territories of suburban parking places, from PP.

In the process of sedimentation (see Fig. 3) the fraction concentration of nominally complex PP sustainably and efficiently decreased (purification effect 94%), while fraction concentration of nominally aliphatic PP became stable practically in 1 day with a very low effect of purification – 20%. Consequently, the purification effect from PP under sedimentation was attributed to disposal of mainly fraction of nominally complex PP, presented apparently, with different heterorganic derivatives of PP. Basing on the experimental data (initial content of PP – 85–341 mg/dm3, sedimentation time – 0–10 days) the graphic rendition of the surface, specifying interrelation of the purification effect of run-off from PP from the territory of the suburban parking areas and sedimentation time under the different initial content of PP, is presented (see Fig. 4).

Concentration of PP, mg/dm

3

Supporting of Ecological Safety of Run-off from the Territory of Objects

15

400 350 300 155

250 200 150

134

100

186

50

128

124

22

16

11

3

6

10

124

69

0 0

1

Time of settling, day

conditionally complex PP

conditionally aliphatic PP

Fig. 3. Dynamics of fractional composition of PP in run-off generated in the parking lot during the settling process.

Effect of purification, %

100 90 80 70 60 50 40 30 20 10 0 85 205 Original content PP, mg/dm3

6

10

3 1 3410 Time of settling, day

Fig. 4. The surface, specifying the dependence of disposal effect of PP from surface sewage water on sedimentation time and initial concentration of PP (averaged experimental data).

According to the theoretical surface (Fig. 4), it is possible to estimate the range of the greatest disposal efficiency of PP from run-off from the territory of parking areas. According to the calculations, the highest purification effect (within the range under study 85–341 mg/dm3) is achieved under the initial concentration of PP within the range 125–210 mg/dm3 on the third day of sedimentation.

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4 Conclusions In the laboratory experimental researches it was found that open settling of run-off (that facilitates vaporization and dispersion of fugitive PP, and also oxygen supply oxidative destruction of PP) in comparison with close settling systems increases effect of PP disposal by 1.3 times, hexane fraction of PP almost by 2 times, separate alkanes C22– C27 – by 2–3 times. Duration of open settling of run-off, formed in the territory of the suburban parking areas, shall be 3–10 days (for achieving of the maximum purification effect 75–80% and without formation of the biofilm). The purification effect of run-off from PP under sedimentation is conditioned by disposal of mainly nominally complex fraction, presented apparently with different heterorganic derivative PP. According to the calculation, the highest purification effect from PP (within the studied range) is achieved under the initial concentration of PP 125–210 mg/dm3 on the 3rd day of sedimentation.

References 1. Kobza, J., Geremek, M.: Do the pollution related to high-traffic roads in urbanised areas pose a significant threat to the local population? Environ. Monit. Assess. 189(1), 33 (2017). https://doi.org/10.1007/s10661-016-5697-1 2. Wang, D., Ma, J., Li, H., Zhang, X.: Concentration and potential ecological risk of pahs in different layers of soil in the petroleum-contaminated areas of the Loess Plateau, China. Int. J. Environ. Res. Public Health 15(8), 1785 (2018). https://doi.org/10.3390/ijerph15081785 3. Yurchenko, V.A., Melnikova, O.G., Bakhareva, A.Y., Yachnik, M.V.: Research of mechanical purification of rain-storm runoffs, formed on the objects of auto-road complex. East Eur. J. Adv. Technol. 6/6(78), 71–77 (2015) 4. Adrion, A.C., Singleton, D.R., Nakamura, J., Shea, D., Aitken, M.D.: Improving Polycyclic aromatic hydrocarbon biodegradation in contaminated soil through low-level surfactant addition after conventional bioremediation. Environ. Eng. Sci. 33(9), 659–670 (2016). https://doi.org/10.1089/ees.2016.0128 5. Stewart, M., Holden, A., Haveroen, M., Ulrich, A.: Quantification of hydrocarbon contaminants meltwater and sediment a city snow pile. J. Environ. Eng. 139, 295–301 (2013). https://doi.org/10.1061/(ASCE)EE.1943-7870.0000606 6. Maximum possible concentrations (MPC) of chemicals in soil: hygienic standards of HS 2.1.7.2041-06 (ratified by the Main state health-officer of Russian Federation), Мoskow (2006) 7. Rysukhin, V.V.: Protection of surface watercourse from contamination with mineral washoff. Extended abstract of dissertation for procuring of scientific degree of PhD in Technical Science. Кyiv (2013) 8. Yu, L., Han, M., He, F.: A review of treating oily wastewater. Arab. J. Chem. 10, S1913– S1922 (2017). https://doi.org/10.1016/j.arabjc.2013.07.020 9. Soda, S., Hamada, T., Yamaoka, Y.: Constructed wetlands for advanced treatment of wastewater with a complex matrix from a metal-processing plant: Bioconcentration and translocation factors of various metals in Acorus gramineus and Cyperus alternifolius. Ecol. Eng. 39, 63–70 (2012)

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10. DBN В.2.5. – 75 Sewage Systems. External networks and building. Substantive provisions of planning (2013) 11. Yu, L.: Analytical chemistry of industrial effluents, Chemistry, Мoskow (1984) 12. Glyaznetsova, Y.S., Zuyeva, I.N., Chalaya, О.N. et al.: IV the International internet is a symposium on a persorption and extraction. 25 April–30 September, pp. 212–218 (2011). http://www.ich.dvo.ru/*isse/2011/images/stories/files/extraction.pdf. Accessed 21 Nov 2018 13. Iurchenko, V., Melnikova, O., Mikhaylova, L., Lebedeva, E.: Contamination and “SelfCleaning” of soils, boarded on the objects of automobile and road complex, from petroleum products. In: Proceedings of the 10th International Scientific Conference, 4–5 May 2017, Vilnius Gediminas Technical University, Vilnius, Lithuania. http://creativecommons.org/ licenses/by-nc-nd/4.0/. Accessed 21 Nov 2018

Comparison of FRAM and CPN Approaches for Analysis of Incidents in Aerodrome Traffic Paulina Rutkowska(&) , Malwina Okulicz and Jacek Skorupski

,

Faculty of Transport, Warsaw University of Technology, 00-662 Warsaw, Poland {pru,mokulicz,jsk}@wt.pw.edu.pl

Abstract. A proactive approach to safety management in transport requires a wider use of information coming from events with low severity of consequences. Therefore, in safety studies, it is necessary to use systemic methods of traffic flow and its control modeling that allow focusing on the planned operation and possible deviations that are inevitable, especially since we are dealing with a sociotechnical system. The aim of the paper was to compare the possibility of analyzing the operation of systems while using various traffic and its control models. The analysis is carried out in terms of traffic safety assessment. For comparison, Functional Resonance Analysis Method (FRAM) and Colored Petri Net (CPN) simulation modeling were selected. Models of the aerodrome traffic system built on the basis of both these approaches allow achieving the main objective of the analysis that is identifying such system function variability scenarios that lead to an undesirable event. However, each of these methods has its advantages and disadvantages. The analysis allows proposing the use of hybrid traffic flow and control models using both the FRAM method and the CPN approach. Keywords: Aerodrome traffic safety
Traffic flow and control modeling Functional Resonance Analysis Method
Colored Petri Nets




1 Introduction Air traffic is carried out in a dynamic environment in which random disruptions affecting the operation may arise. The organization of the air traffic system enforces the existence of safety barriers, which prevent from accidents. Therefore, a good source of information for studying the safety of the air transport is conflict situations and incidents that are more frequent. Even if they did not lead to an accident, they provide data on the system’s resilience. The research on incidents allows identifying those safety barriers that prevented the accident but require strengthening – technical, legal or organizational. It also allows finding threats that have not been identified so far. The study of incidents is in line with the Safety II proactive approach, which becomes popular in safety research. Its main assumption is to accept that the system may operate differently than planned by its developers. The dangerous event is treated as a special case of system functions outputs variability. But generally, such variability © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 18–28, 2020. https://doi.org/10.1007/978-3-030-38666-5_3

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should be treated as something normal and unavoidable, especially when humans are involved. Therefore, according to Safety II, the focus is on understanding the operation of the system. Analysis of an adverse event focuses on the effects of possible variability of the functions. For this type of analysis, the Functional Resonance Analysis Method (FRAM) is used. It is a systemic method that goes beyond cause-effect relations. It helps describing the possible variability of functions and searching for combinations of variabilities (called the functional resonance), which may lead to the unsafe state of the system. The analysis assumes different levels of variability determined in a qualitative way. Another approach to systems safety is their formal analysis using Colored Petri Nets (CPN). It allows analysis of concurrent processes, whereby the simulation of the system operations allows observing the variability of its functions. In contrast to the FRAM method, in CPN the functions variability can be described quantitatively. In this paper, we study the aerodrome traffic, which is a complex sociotechnical system. We focus on one aspect of this system – on the ground handling vehicle whose route intersects the route of the aircraft. We developed two models of this system using FRAM and CPN. They allow us to compare both methods in terms of usefulness for analyzing the transformation of a traffic situation into an incident or an accident.

2 Aerodrome Traffic The object of the analysis is the aerodrome traffic system where both aircraft and ground support equipment (GSE) vehicles may operate at the same time. As the aerodrome traffic, we will understand the traffic of aircraft on taxiways, especially taxiways near and on the apron, as well as the traffic of all vehicles on the apron and on service roads. The airport management is responsible for the organization of vehicle and pedestrian traffic, while the ground air traffic controller (GND) is responsible for the aircraft traffic. Only authorized persons, properly trained, and only in a strictly defined zone may participate in aerodrome traffic. The movement is limited to the necessary cases resulting from the work performed. According to [5], vehicles movement on runways and taxiways and their crossing, can only be performed with the ATC controller’s permission, and on the apron with the permission of the airport manager. All vehicles must be appropriately marked and may use only special routes at airside of the airport. Every employee moving around the airport must be extremely cautious and follow signs, signals and signaling lights. Each vehicle must give way to towed, pushed, as well as taxiing, taking-off and landing aircraft. Each airport can establish their own speed limits in various areas of the airport, specifying them in the operating manuals of vehicle and pedestrian traffic.

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3 FRAM The Functional Resonance Analysis Method (FRAM) was developed by Hollnagel [4] for studying complex socio-technical systems. Creating a model and analyzing the system with the use of that model consists of the following stages: 1. 2. 3. 4.

Identification of basic system functions. Checking the consistency and completeness of the constructed model. Description of possible variations of the function. Analysis of the functions and their couplings variability for determination of functional resonance. 5. Analysis of the possibility of affecting the functional resonance to achieve the desired effects. Each function performed is described by six aspects: 1. Input (I) – the value that begins the function execution. 2. Output (O) – result of the function. 3. Preconditions (P) – conditions that must be met before the function can be performed. 4. Resources (R) – required or used during the implementation of the function. 5. Time (T) – defines the start or end time of the function. 6. Control (C) – methods, constraints and procedures that define how the function is controlled.

There is a group of papers that use the FRAM method in application to aviation. Yang et al. [12] used the method for analyzing the Minimum Safe Altitude Warning system. Studic et al. [10] demonstrated the need for a systemic approach to managing the risk of ground handling services. They developed a hybrid model of apron safety management in which FRAM was also used. Recently, Patriarca et al. [6] suggest using a Monte Carlo simulation to extend the FRAM with quantitative analysis. The extension of research proposed in our paper consists to use colored Petri nets for quantitative analysis. As mentioned earlier, our analysis of the aerodrome traffic system will be focused on searching for the mechanism of creation of a certain class of aviation events. Therefore, in the model presented in Sect. 5.1 we will use the FRAM approach proposed in [11] named FRAMA. It contains some detailing of the basic method, which allow easier analysis of aviation incidents. The analysis is carried out in seven steps. 1. 2. 3. 4.

Identification of the system functions by the analysis of its operation “as expected”. Description of the aspects of functions used. Determining the couplings between functions. Identification of variability in function operation. In general, four categories of function variability are distinguished: a. The function works according to the time and accuracy requirements. b. The function is not executed – it does not give an output value or is performed insufficiently (with unacceptable precision). c. An incorrect function is performed, that gives unacceptable output data.

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d. The correct function is performed sooner or later than it is required or out of order. 5. Determination of the variabilities of aspects affecting the performance of functions. 6. Definition of safety constrains. This step allows determining if there is a violation of restrictions. If so, the system goes into a state in which an accident may occur. 7. Determination of undesirable scenarios, by analyzing the possibility of cumulative variability.

4 CPN Petri nets allow formal analysis of complex concurrent systems, so they can be used to model traffic flow and control in transport. Petri net are built on bipartite directed graph. It consists of places, transitions and arcs that allow description of the static structure of transportation processes and tokens that are used to model their dynamics. The Colored Petri Net (CPN) is an extension to the low-level Petri net. In CPN, tokens have colors, so that they may be distinguished. Colors correspond to data structures analogous to programming languages. CPN can be written as: SAT ¼ fP; T; A; M0 ; s; X; C; C; E; R; r0 g;

ð1Þ

where P – set of places; T – set of transitions T \ P ¼ ;; AðT  PÞ [ ðP  T Þ – set of arcs; M0 : P ! Z þ  R – marking which defines the initial state of the system; s : T  P ! R þ – function determining the static delay relating to activity (event) t; X : T  P ! R þ – random time of carrying out an activity (event) t; C – finite set of colors which correspond to the possible properties of tokens; C – function determining what kinds of tokens can be stored in a place: C : P ! C; E – function describing properties of tokens that are processed; R – set of timestamps (also called time points) RR; r0 – initial time, r0 2 R. There are papers that use CPN to analyze air traffic processes. For example, Davidrajuh & Lin [2] used them to optimize air traffic management at Evenes airport in Norway. Similarly, in [3] Petri nets were used to model NextGen ATC system. In turn, in [9] a method was developed that allows analysis of sequence of landing aircraft. Petri nets are also used for modeling enroute air traffic [1]. For modeling of aviation incidents and accidents Petri nets were used in [8].

5 Models of a Conflict Situation in Aerodrome Traffic The incident No. 1099/2015 took place at the Warsaw Chopin Airport in 2015. The participants of the incident were: a fuel tanker truck (TT) and Embraer 170 aircraft (EMB). The employee of a ground service agent operating the TT was driving on the service road parallel to the taxiway used by EMB taxiing to the parking stand. Then the TT driver turned left and crossed the taxiway without stopping in front of it. This forced the EMB crew to limit the speed significantly. None of passengers or crew members were injured. The report prepared and published by the State Commission on

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Aircraft Accident Investigation [7] claims that the cause of the incident was the failure of the tanker driver to maintain proper caution and giving way to the taxiing aircraft. The following sections present models of the incident which were developed using the FRAM and CPN methods and used to compare their applicability to the analysis of aerodrome safety. The idea behind both models is to describe the conflict situation at the intersection of the taxiway and the service road with the proper use of all rules by the taxiing aircraft crew and the GSE vehicle driver. Then we analyze the effects of deviations from the correct situation resulting from the precision variability and time variability of the performed operations. These variabilities are normal and cannot be avoided in a real-life system. Our analysis focuses on searching for combinations of variabilities that can lead to an accident. Finding them allows proposing proactive preventive measures. 5.1

The FRAM Model

As explained in Sect. 3, the creation of a FRAM model describing the proper operation of the system required its specification by: – system functions identification, – description of the aspects of the functions, – determining the couplings between functions. These steps are summarized in Table 1, while the graphical form of the model created with the use of FRAM Model Visualiser (FMV) program is shown in Fig. 1. Table 1. Description of functions, aspects and couplings in FRAM model of 1099/2015 incident Function F1 - EMB start taxiing F2 - EMB make sure that CA is free F3 - EMB take the CA F4 - EMB continue taxiing F5 - TT turn towards ZB2 F6 - TT make sure that CA is free F7 - TT stop F8 - TT continue driving

Input – EMB in DA EMB – CA free EMB in CA – TT in DA

TT in DA TT – CA free DA – Decision Area, CA – Collision Area

Output EMB in DA EMB – CA free EMB in CA EMB outside CA TT in DA TT – CA free TT stands –

Precondition – – –

Time – TT stands –

–

–

– EMB outside CA EMB in DA –

– – – –

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Fig. 1. FRAM model of the incident 1099/2015.

5.2

The CPN Model

As described in Sect. 4, the creation of a model of airport traffic flow and control as a colored Petri net for the analysis of an accident possibility at the intersection of taxiway and service road, requires the definition of: – places that characterize system states, – transitions representing events occurring in the system, – arcs determining conditions necessary for the occurrence of an event and its effects. A graphical representation of the model created in the CPN Tools 4.0 environment is presented in Fig. 2, while Table 2 provides an explanation of selected places, transitions and arcs.

Fig. 2. CPN model of the incident 1099/2015.

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Table 2. Description of places, transitions and arcs in CPN model of 1099/2015 incident. Object

Meaning

Object

Meaning

Transition Tx Place EMB DA Transition EMB Cnt Transition Brkng Place TT Wtg

EMB is taxiing EMB in DA EMB is continuing taxiing EMB is braking emergency TT is standing

Place Incid Place TT DA Transition Stop Transition TT Cnt1 Transition TT Cnt2

An air incident occurred TT in DA TT is stopping TT is not stopping TT is continuing driving (after stopping)

6 Analysis of the Accident Occurrence Possibility As already mentioned, the analysis is aimed at seeking such deviations from the proper operation of the system, which may lead to an accident. Possible variabilities of functions must be defined and analyzed in a way adequate to the nature of both methods. However, the purpose of this paper is not a complete analysis of the studied class of events, but a comparison of both methods. Therefore, in each of them we consider the same, but only selected function variabilities, which can lead to unfavorable functional resonance (FRAM) or achievement of unfavorable final marking (CPN). Finally, we will compare the effectiveness of both approaches. 6.1

FRAM Analysis

To check the possibility of an accident the analysis consisting in subsequent steps of the method [11] was conducted: – determining the variability of functions and their propagation through aspects (steps 4 and 5), – establishing safety constrains (step 6), – determining the undesirable scenarios (step 7). Based on the analysis of functions performed by the system, all their potential variabilities were determined. Table 3 shows the correct outputs and variabilities of these functions, which can contribute most to the accident. Table 3 shows the variabilities within the function itself. They may be amplified by the influence of variabilities of aspects which are the inputs of the function. This way, the variability propagates. A part of the analysis made is shown in Table 4. The variabilities of outputs in Table 3 and Table 4 indicate where the deviation from the operation “as expected” may occur. However, not every deviation causes the system to go into an unsafe state. Therefore, in the next step, there is a need to specify safety constraints that allow determining whether a specific combination of variabilities can cause an incident or an accident. There are several factors leading to an incident or an accident for the analyzed event. For example, for the presented part of the analysis, those are:

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Table 3. Examples of functions variability. Function Variability Description F2 F2V0 EMB correctly knows that CA is free F2V1 EMB is convinced that CA is not free (and it is) F2V2 EMB is convinced that CA is free (and it is not) F4 F4V0 EMB is continuing taxing on time F4V1 EMB is continuing taxing too late F6 F6V0 TT correctly knows that CA is free F6V1 TT is convinced that CA is not free (and it is) F6V2 TT is convinced that CA is free (and it is not) F7 F7V0 TT is stopping on time F7V1 TT is stopping too late F7V2 TT is not stopping at all

Table 4. Example of variability propagation rules. Function Input Precondition Time F2 F1 output – F7V0 – F7V1 – F7V2 F6 F5 output F4V0 – F4V1 –

Output F2V0 F2V1 F2V1 F6V0 F6V1

– EMB crew is convinced that CA is not empty (F2V1) and implements emergency braking. This means an incident, as this maneuver should not take place and potentially could damage the equipment or injure passengers. – Both the EMB crew and the TT driver are convinced that the CA is empty, and in fact it is not (F2V2 and F6V2). In this situation, continuation of the movement of both vehicles follows and an accident involving the collision is possible. The safety constraints allow defining scenarios leading to an incident or accident. In our case, these events consist in an emergency stop of the EMB (an incident) or collision of vehicles (an accident). There is a number of these scenarios and they can be described using appropriate transition graphs. However, all of them contain one of the combinations of factors outlined above. 6.2

CPN Analysis

In this section, studies on time variabilities in the CPN model will be presented. Simulation experiments consisted in modifying the duration of actions modeled by transitions. Using the functionality of the CPN model, it was assumed that they are represented by random variables with discrete probability distribution over a given interval.

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Examples of simulation results are presented in Table 5. They were chosen to compare results with the FRAM model. For this purpose, a description of the simulation results in accordance with the nomenclature adopted in FRAM has been added in the last column. The remaining columns show the time when elementary events occurred: EMB DA – EMB reaches the DA, TT DA – TT ends the turn, TT Wtg – TT stops, TT Pass – TT passes the CA. Table 5. Sample results of experiments with the CPN model. ZB2 0 0 2 2 4 4 6 6 6 8 8 8 10 10

EMB DA TT DA TT Wtg TT Pass Description 10 8 13 – F7V1 & F2V1 10 5 9 – F7V0 = safe 8 10 13 – F7V0 = safe 9 6 11 – F7V1 & F2V1 14 10 11 – F7V0 = safe 11 9 12 – F7V1 & F2V1 11 8 13 – F7V1 & F2V1 16 5 – 12 F7V2 & F2V0 14 9 10 – F7V0 = safe 18 10 11 – F7V0 = safe 18 7 – 17 F7V2 & F2V0 16 7 – 17 F7V2 & F2V2 17 8 – 18 F7V2 & F2V2 20 9 – 17 F7V2 & F2V0

= incident

= incident = incident = incident & F6V0 = safe

& F6V0 = safe = accident = accident & F6V0 = safe

The results presented in Table 5 are ordered in relation to the time of the EMB appearance in the analysis area. This allows observing the dependence of the function variability on its initial position. A similar analysis was carried out for an identical situation as in the FRAM model, when the initial distance of both vehicles from the collision point is the same. It confirmed quantitatively the dependence that the moment of TT’s stoppage should be earlier than the moment EMB emerged in the decision area.

7 Summary and Conclusions The paper presents the results of the research, which aimed at analyzing the aerodrome traffic safety when the taxiing aircraft and the GSE vehicle are on the collision routes. We used two models of this potentially collision situation made in two different techniques – FRAM and CPN. The aim of the research was to compare these methods for proactive analysis of aerodrome traffic control systems. Both methods allow to track the proper system operation when the variability of its functions is low, and it does not propagate, or there is no amplification of variability that may lead to an accident. Thanks to this, it is possible to better understand the way the system works “as expected”.

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In the FRAM analysis, many scenarios can be distinguished, which have a common sequence of variabilities leading to a hazardous event: – false conviction of the EMB crew that the TT will not stop and applying emergency braking (F2V1 variability) or, – false conviction of both the EMB crew and the TT driver that the collision area is empty and continuation of movement (variability of F2V2 and F6V2). Finding these crucial variabilities is beneficial for the proactive approach to the safety of the analyzed system, as it allows focusing on the most important problems. The former case results in an incident, in the latter also an accident is possible. The former case is probable, while the latter case is rather not, as it would require a significant deviation from the expected action. However, the FRAM method does not allow to estimate these probabilities. If there is a need to prioritize risk to determine the order of preventive measures implementation, this is an inconvenience of the FRAM method. A second drawback of this method is a relatively large number of scenarios to consider. When analyzing using the CPN model, it is possible to quantify the variability of system functions. This is very beneficial, because it allows defining more precisely what kind of preventive measures are necessary. For example, thanks to the analysis it is possible to determine the distance from the collision area where the taxiing aircraft should pay special attention to moving GSE vehicles. An additional warning signs may be installed in this zone. Another advantage of using the CPN-based approach is the possibility of simulating the variability by their random generation according to the given probability distribution. With a sufficiently large number of simulation runs, we can observe combinations of variabilities that are rare and could remain undetected when analyzed by other methods. The simulation approach also allows estimating the frequency of their appearance, and that eliminates the disadvantage of the FRAM method. The disadvantage of the method based on CPN is the lack of direct information to what variability of the output may the variability of aspects lead. The interpretation of variability in accordance with the FRAM approach requires additional analysis. A comparison of the FRAM and CPN methods shows that using both methods together is a good approach. FRAM may be the primary one, and CPN may be its complement allowing more precise estimation of variabilities. Alternatively, CPNbased approach may be the primary one, and FRAM may be complementary, delivering a synthetic description of those situations that require proactive prevention. The development of such hybrid methods is planned in further stages of research. Acknowledgements. The research, which became the basis for preparation of this article, was partially carried out within the research project POIR.04.01.04-00-0059/16 “SimAirHandling – Innovative mobile training simulator for ground handling operators” financed by the Polish National Centre for Research and Development under the Smart Growth Operational Program 2014-2020, co-financed by the European Regional Development Fund.

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References 1. Bakker, G., Obbink, B.K., Klompstra, M., Blom, H.: DCPN specification of a free flight air traffic operation, working document. Technical report. National Aerospace Laboratory NLR, Amsterdam (2004) 2. Davidrajuh, R., Lin, B.: Exploring airport traffic capability using Petri net based model. Expert Syst. Appl. 38(9), 10923–10931 (2011) 3. Hang, W.: Modeling next generation air traffic control system with Petri net. New Jersey Institute of Technology, Department of Electrical and Computer Engineering (2011) 4. Hollnagel, E.: FRAM – The Functional Resonance Analysis Method. Ashgate, Farnham (2012) 5. ICAO: Aerodrome Design and Operations. Annex 14 to the Convention on International Civil Aviation, Aerodromes vol. I, Montreal, Canada (2016) 6. Patriarca, R., Di Gravio, G., Costantino, F.: A Monte Carlo evolution of the Functional Resonance Analysis Method (FRAM) to assess performance variability in complex systems. Saf. Sci. 91, 49–60 (2017) 7. PKBWL: State Commission on Aircraft Accident Investigation. Information on the Occurrence No: 1099/2015, Warszawa (2015) 8. Skorupski, J.: The risk of an air accident as a result of a serious incident of the hybrid type. Reliab. Eng. Syst. Saf. 140, 37–52 (2015) 9. Skorupski, J., Florowski, A.: Method for evaluating the landing aircraft sequence under disturbed conditions with the use of Petri nets. Aeronaut. J. 120, 819–844 (2016) 10. Studic, M., Majumdar, A., Schuster, W., Ochieng, W.Y.: A systemic modelling of ground handling services using the functional resonance analysis method. Transp. Res. Part C Emerg. Technol. 74, 245–260 (2017) 11. Tian, J., Wu, J., Yang, Q., Zhao, T.: FRAMA: A safety assessment approach based on Functional Resonance Analysis Method. Saf. Sci. 85, 41–52 (2016) 12. Yang, Q., Tian, J., Zhao, T.: Safety is an emergent property: Illustrating functional resonance in Air Traffic Management with formal verification. Saf. Sci. 93, 162–177 (2017)

Influence of the Information Disruptions in A-CDM System on the Time of Readiness for Take-off Malwina Okulicz(&) , Paulina Rutkowska and Jacek Skorupski

,

Faculty of Transport, Warsaw University of Technology, 00-662 Warsaw, Poland {mokulicz,pru,jsk}@wt.pw.edu.pl

Abstract. The concept of Airport Collaborative Decision Making (A-CDM) is a joint venture between Airports Council International Europe, European Organization for the Safety of Air Navigation, International Air Transport Association and Civil Air Navigation Services Organization. It was implemented in many airports in the world as a response to the growing amount of information necessary for the proper functioning of an airport. The essence of the A-CDM system is to provide information on stages of the flight and to collect them in a shared database. The aim of the paper was to analyze the process of generating, transmitting and using data in terms of possible disturbances and the effects they may bring for punctuality of the take-off operation. The research was divided into two stages. The first uses the developed model in the form of a Petri net for analyzing the impact of information disruptions in A-CDM on target off-block time (TOBT) which is crucial for the on-time takeoff operations. In the second stage, a simulation model of the aircraft pushback and taxiing process was used to analyze the impact of TOBT disruption on the readiness to take-off. Following a series of simulation experiments quantitative results showing both these dependencies were obtained. It has been shown that even minor disturbances in the A-CDM can cause changes to the TOBT, and thus delay the moment the aircraft is ready to leave the parking stand. In turn, these small delays may escalate during pushback and taxiing which results in noticeable delays in the take-off. Keywords: Air traffic
Airport operations
Petri nets
Simulation modeling
Airport Collaborative Decision Making
A-CDM

1 Introduction Airports are complex elements of the transport system which includes infrastructure, management and control of passenger and aircraft traffic, and maintenance processes. Due to the constantly increasing air traffic, the amount of data necessary for the proper functioning of the airport is increasing. Their timeliness and integrity are extremely important, with data being produced and consumed by numerous entities performing their tasks at airports. Therefore, the emphasis is placed on improving the exchange of © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 29–39, 2020. https://doi.org/10.1007/978-3-030-38666-5_4

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information between them. A-CDM (Airport Collaborative Decision Making) system constitutes a comprehensive and systemic solution. Due to the complexity of the system and its dispersed architecture, it may be sensitive to several types of interference. The biggest threat is the interruption of information flow. In such cases there may be significant delays of flight operations. In the studies so far, mainly statistical methods [11] and models based on mixed linear programming were used to analyze delayed taxi times and departure times [7]. Under uncertainty, in the presence of numerous disturbing factors, it is beneficial to use simulation methods to analyze real-time traffic situations. This type of simulation analysis was carried out, for example, in [6] to determine the most advantageous airport configuration, while identifying potential problems and capacity constraints. The strategic goal of this work is to examine to what extent, even the smallest deviations from the planned traffic schedule can affect airport operations. In this study, the impact of disturbances in the A-CDM on the readiness for take-off was analyzed. It depends on the taxi time, and this in turn depends on the determination of the TOBT (Target Off-Block Time). In the first stage of research, the model in the form of a Petri net was used to analyze possible sources of disturbance and its effects depending on the place of using the TOBT value. In the second stage, a simulation model was developed and experiments using CAST (Comprehensive Airport Simulation Technology) were carried out to analyze taxi times depending on the disturbance [1].

2 The A-CDM System The A-CDM system is a complex anthropotechnical system whose fundamental components are: users involved in ground services, devices used by them, communication systems and a common database called Information Sharing Platform (ISP). The ISP allows one to closely monitor the progress of flight operations in real time. The entities involved in the A-CDM concept are [4]: – – – – –

Ground Handling (GH), Air Traffic Control (ATC), Aircraft Operator & Airlines (AO), Airport Operations Centre (AOC), Network Manager Operations Centre (NMOC).

These entities, on the one hand, modify information in the ISP, and on the other hand use it to plan their activities depending on its content. 2.1

Information Exchange Process

For each piece of information, including TOBT analyzed in this article, one can define the process by which it is created, transmitted and used (Fig. 1). The process starts with the identification of an event, which is the basis for updating the data. Such identification may be made by a person or it may be carried out automatically. The second stage of the process is the introduction of this information to the A-CDM system via an intermediary device (mobile operator terminal, system console). The next steps are the

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transmission of information to the central database and its update. Data prepared in this way are consumed by system users. This involves the transmission of information to peripheral output devices and their presentation on these devices.

Fig. 1. Information flow diagram within A-CDM system (own study).

The effectiveness of A-CDM is determined by the precise and timely introduction of key data, called Milestones (MS), describing the various stages of the flight operation. They are presented in Table 1. Table 1. A-CDM Milestones (own study based on [4]). Milestone number 1

Flight stage

2

ATC Flight Plan activation Flight data update

3 4 5 6 7 8

Take off from outstation Airborne Final approach Landing Taxi-in In-block

Milestone number 9 10 11 12 13 14 15 16

Flight stage Deboarding Ground handling service Boarding Ground handling ends Start-up request Pushback Taxi-out Take off

Data used in the A-CDM system are short information about the planned ones and the actual time of occurrence of traffic events. Any inconsistencies have a significant impact on the correctness of activities of the participants of the A-CDM system. 2.2

Information Disturbances in the A-CDM System

At each stage of information processing in the A-CDM system, data may be distorted or lost. The causes of irregularities may include adverse weather conditions, failures of

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technical infrastructure or simple human error [8]. Identification of interferences in the information flow will be presented for the TOBT, as being extremely important from the point of view of the punctuality of the flight operation. The following inconsistencies can be distinguished: – total lack of TOBT in ISP, – lack of information about TOBT on the display of Visual Docking Guidance System, – no update or too late update given in the ISP, – incorrect estimation of TOBT – too high or too low value, – intentionally incorrectly entered value, – disappearance of data in the Information Sharing Platform.

3 Information Flow Model in A-CDM The information exchange process discussed in Sect. 2.1 can be used to analyze the punctuality of the departure dependent directly on the time of readiness for take-off. Therefore, a model of this process was developed in the form of a colored, timed, hierarchical Petri net with priorities. The overall structure of this net is as follows: SATC ¼ fP; T; A; M0 ; s; C; C; G; E; R; r0 ; Bg;

ð1Þ

where P – set of places; T – set of transitions T \ P ¼ £; AðT  PÞ [ ðP  T Þ – set of arcs; M0 : P ! Z þ  R – marking defining the initial state of the system; s : T  P ! R þ – function determining the static delay relating to activity (event) t; C – finite set of colors which correspond to the possible properties of tokens; C – function determining kinds of tokens stored in a given place: C : P ! C; G – the conditions that must be fulfilled for a given event to occur; E – function describing the properties of tokens that are processed; R – set of timestamps (also called time points) R  R; r0 – initial time, r0 2 R; B : T ! R þ – function determining the priority of a transition. The developed model has been computer-implemented in the CPN Tools 4.0 programming environment [5, 9, 10]. Such a model allows simulation experiments to be carried out, which will show a quantitative relationship between the disturbances in A-CDM and the time of readiness for take-off. 3.1

Data Update in ISP

The developed model of information flow within the A-CDM allows visualization of the flight process and analysis of the related time parameters [2]. It is a mesoscale model that allows to do research on information anomalies, information overflow and information distortion. The form of the Petri net representing selected milestones responsible for updating the TOBT [4] is presented in Fig. 2. This net consists of two parts. The first one shows the model of the aircraft movements. Transitions (Flight, Taxiing, Deboard, Service, Board and Pb Clear) represent phases of the flight, ground movements and ground handling. Completion of each phase indicates the occurrence of

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the appropriate state of flight operations (places Touch down, On block, Empty, Ready, Boarded, Off block) and is equivalent to achieving the appropriate milestone (places MS6, MS8, MS9, MS10, MS11, MS14).

Fig. 2. Information flow model within A-CDM milestone approach (own study).

The lower part of Fig. 2. shows the procedure and mathematical function used to update the TOBT. In earlier phases, this function contains many variables for which a predicted value should be assumed. For example, when updating the TOBT value in the milestone 6 (Landing), it is necessary to approximate the time of five successive service steps – taxiing (variable PTaxiTime), deboarding (PDeboardTime), ground handling (PServiceTime), boarding (PBoardTime) and pushback (PPbClearTime). It is obvious that the TOBT value placed in the ISP at the time of the touchdown is subject to high uncertainty. On the other hand, the update of TOBT at the time of reaching the milestone number 11 (Boarding), carried out after finishing passenger boarding is much more accurate, as it contains only one variable necessary for approximation. 3.2

Use of Information in A-CDM

The essence of the A-CDM system is the participation of various services in updating data in the ISP, and at the same time the ease of their use. Table 2 presents the cases of using the TOBT for planning and organizing the work of A-CDM participants identified for Warsaw Chopin Airport. Real-time field measurements allowed to determine the activation moments of operations and, as a result, to draw the first conclusions. The number of activities dependent on the TOBT is significant and the planning horizon is not compatible with the sequence of activities. For example, determining the position in the departure queue takes place as the first of the activities. At the same time, the departure itself is the last of all activities. Any inconsistencies in the data with

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respect to the TOBT may result in distortions in the ground handling process and ultimately delay of take-off. In extreme cases, negative effects on safety are also possible. In the moments specified in the last column of Table 2, appropriate actions of individual services are taken. They consist in either starting certain maintenance activities or planning them. An example of a Petri net illustrating the use of TOBT by ground handling is presented in Fig. 3. Table 2. TOBT usage by A-CDM participants (own study). Information consumer Air Traffic Controller Ground handling Airport Management Ground handling Ground Coordinator Ground handling Aircraft Operator Ground handling Aircraft operator

Operation Aircraft assignment in departure queue Planning passengers’ transport to aircraft Final stand allocation Resources arrangement for aircraft servicing Follow Me vehicle departure to parking stand Tanker reservation for refueling time Calling ATC for pushback clearance Delivering loadsheet to pilot’s cockpit Beginning of departure procedures

Time [min] TOBT-120 TOBT-100 TOBT-90 TOBT-80 TOBT-65 TOBT-60 TOBT-15 TOBT-15 TOBT-5

Fig. 3. Petri net modeling the use of TOBT by the handling agent (own study).

The individual transitions (Fuel, LdSh, Service and Pax D) are responsible for detecting the moment when action (or planning the action) should be taken. Their result is placing the token in place, which means readiness to start specific maintenance activities (respectively: Fuel rdy, Ldsh rdy, Svc rdy and Bus rdy). The current stage of the research assumes that necessary resources are available without any restrictions.

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35

Simulation Experiments

Thanks to experiments, the information about the moment of starting departure procedure is obtained. This value depends on the duration of maintenance activities, and on possible disruptions in the ISP. The nominal TOBT and the effect of disturbances for the time when the aircraft may leave the stand for departure (actual off-block time AOBT) has been determined. The results are presented in Table 3. In these experiments, the random nature of the execution time of traffic and service operations has not yet been considered. This requires taking field measurements and will be included in further publications. Table 3. Results of experiments using the information flow model in A-CDM (own study). Type of experiment No interferences – nominal value Too late update of data after completion of deboarding (MS9) No update of the data after completion of ground handling (MS10) Too high data value estimated after landing (MS6) Data value too small estimated after locking the airplane wheels (MS8) Intentional distortion of data after termination of the boarding (MS11) After 120 min of simulation, the data is lost for 20 min

AOBT [min] 194 197 194 196 194 204 201

Simulation results clearly indicate the possibility of delay in leaving the parking stand in the event of disturbances in the process of TOBT information exchange. The amount of delay depends on the location of the disturbance, as well as on its type. Presented deviations from nominal time are small due to slight (3–5 min) distortion. In further research plans, consideration is given to the randomness of the duration of operations, as well as the limitations in the availability of hardware and human resources.

4 Analysis of the Impact of TOBT Disturbance on the Time of Readiness for Take-off As the analysis presented in Sect. 3 showed, the disturbances in the information on traffic events sharing process may cause delayed readiness to leave the stand. In this section, the impact of possible delay on aircraft maneuvers followed is analyzed. The ground handling agent and the ATC are responsible for the maneuvers on the apron and traffic on taxiways. The location of parking stands results in a variable taxi time. Also, the current situation in the airfield, has an impact on this variability. The ATC decides about the sequence of pushback from parking stand and taxiing to the runway threshold. Based on the TOBT, the ATC queues individual aircraft for departure, considering the preferences of the air carrier, aircraft operator and minimizing the taxiway congestion if possible. In addition to the traffic benefits, it also reduces noise and fuel consumption [3, 4].

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The difference between AOBT and TOBT used to sequencing take-offs has an impact on the formation of queues on taxiways, which results in a longer taxiing time and delay in take-offs, but also in blocking parking stands. This may result in the need of stand reallocation for subsequent arriving aircraft. Accumulation of this type of phenomena can significantly lower the runway capacity and airport service capability. To evaluate quantitatively the impact of possible delay in leaving the parking stand in relation to the nominal value of TOBT for the estimated taxi-out time (EXOT) and for delaying the calculated take-off time CTOT, a simulation model was created of an exemplary airport shown in Fig. 4. It includes the last three Milestones of the A-CDM concept. The case studies were carried out in a specialized CAST simulation program. This program is a software consisting of modules for airport simulation, capacity planning, resource allocation and real-time forecasting of airport operations [1]. The simulation results were presented for two scenarios, the essence of which is presented in Fig. 5.

Fig. 4. Scheme of modeled aircraft movement to departure (own study).

Fig. 5. Scenarios for leaving the aircraft stand: (a) on the planned TOBT time (b) sooner or later than the planned TOBT time (own study).

In Scenario 1, there is a situation when the aircraft leaves the stand just after leaving from blocks, at the planned TOBT time. However, in Scenario 2, disturbances have

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been introduced, whose values are comparable to the values obtained as a result of the analysis in Sect. 3.3 (from 2 to 10 min). The AOBT was changed for 7 aircraft. The assumptions for the simulation model of traffic at the analyzed airport are: 1. 2. 3. 4. 5.

The analysis includes approximately 140 pushing and taxiing operations. The time of performing the pushback operation is constant for all aircraft. The routes chosen by aircraft in the direction of the runway are the same. The allocation of parking stands is fixed earlier and invariable in both scenarios. All take-offs are carried out on one direction of the runway.

The results for Scenario 1, in which all the pushback and taxi operations started in accordance with the nominal TOBT are shown in Fig. 6. Results for Scenario 2, in which the pushback and taxi operations were subject to the effects of disruptions in the information exchange within the A-CDM are presented in Fig. 7. They show the average taxiing delay, and thus the delay of readiness for take-off. As one can see, for Scenario 1 the largest delay in taxi time was 1 min 37 s. This is a slight deviation from the schedule, which does not lead to disturbance of daily airport traffic. However, for Scenario 2 there was a significant increase in the peak of the taxi delay time (10 min 28 s). In addition, the time of these maximum delays has moved for the evening hours, which is due to the domino effect initiated by the delay of only a few air operations at different times of the day. Compared to Scenario 1, the average taxi-out time has also increased, which translates into the efficiency of using the runway, and further the operational capabilities of the airport. This indicates the need for ongoing monitoring of the information exchange, hence flight operation processes and the prevention of possible disruptions already at the early stages of the A-CDM system implementation.

Fig. 6. Results in Scenario 1 – average delay time in the queue for departure (own study).

Fig. 7. Results in Scenario 2 – average delay time in the queue for departure (own study).

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5 Summary and Conclusions The paper presents a two-stage analysis of the impact of information disturbances in the A-CDM system on the time of readiness for take-off. Analyzes of this kind are useful to all participants of the A-CDM concept, who can identify those places in the structure of information flow, which are particularly susceptible to interference and which have the greatest impact on the success of the system implementation. Thanks to this, they will be able to plan their activities better. The first phase involved modeling of the traffic and information flow, including the data update and their use. The model in the form of a colored, timed, hierarchical Petri net with priorities was developed. Simulation experiments were conducted showing quantitatively the influence of disturbances in the process of generating, transferring and using information about TOBT on the final readiness to leave the parking stand. The second phase included modeling of pushback and taxiing for departure maneuvers following notification of readiness to leave the aircraft stand. Considering the results of the first phase, two simulation experiments were carried out, showing the impact of TOBT interferences on the time of readiness for take-off. In total, both phases allowed to show the impact of information disruptions in the A-CDM system on the time of readiness for take-off. The results obtained indicate that disruptions in the information processing in A-CDM cause TOBT delays, what in turn causes an increase in the average taxi time and a significant delay in flight operations, mainly due to longer time spent in the departure queue. Even relatively small disturbances of the TOBT cause lengthy delays of the readiness for take-off. This calls for further research aimed at seeking tools to eliminate disruptions in the processing of data in A-CDM system or to mitigate their effects. The mesoscale model used in the first phase of the analysis allows for a detailed analysis of the internal structure of the system, including the disturbance origin and their escalation or mitigation. This may constitute a wider point of view to consider in the future and initiate challenges for airport authorities.

References 1. ARC, CAST Aircraft – Aircraft Flow and Process Simulation, Airport Research Center. https://arc.de/cast-simulation/. Accessed 04 Jan 2019 2. Durugbo, C., Alcock, J., Tiwari, A.: Modelling information flow for organisations: A review of approaches and future challenges. Int. J. Inf. Manag. 33(3), 597–610 (2013) 3. EUROCONTROL: Airport CDM Applications Operational Concept Document, Edition 3.0, Brusseles (2006) 4. EUROCONTROL: Airport CDM Implementation - The Manual, Version 5.0, Brusseles (2017) 5. Jensen, K., Kristensen, L., Wells, L.: Coloured Petri Nets and CPN Tools for Modelling and Validation of Concurrent Systems. Int. J. Softw. Tools Technol. Transfer 9(3–4), 213–254 (2007) 6. Mota, M., Boosten, G., de Bock, N., Jimenez, E., de Sousa, J.: Simulation-based turnaround evaluation for Lelystad Airport. J. Air Transp. Manag. 64A, 21–32 (2017)

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7. Murça, M.: A robust optimization approach for airport departure metering under uncertain taxi-out time predictions. Aerosp. Sci. Technol. 68, 269–277 (2017) 8. Okulicz, M., Skorupski, J.: Analysis of possible interferences in A-CDM information flow. Scientific Works of Warsaw University of Technology. Transport 122, 1–14 (2018). (in Polish, in press) 9. Ratzer, A., Wells, L., Lassen, H., Laursen, M., Qvortrup, M., Stissing, M., Westergaard, M., Christensen, K., Jensen, K.: CPN Tools for Editing, Simulating, and Analysing Coloured Petri Nets. In: 24th International Conference on Applications and Theory of Petri Nets, LNCS, vol. 2679, pp. 450–462. Springer, Heidelberg (2003) 10. Skorupski, J.: Quantitative methods of air traffic incidents analysis. Warsaw University of Technology Publishing House, Warsaw (2018). (in Polish) 11. Zhang, Y., Wang, Q.: Methods for determining unimpeded aircraft taxiing time and evaluating airport taxiing performance. Chin. J. Aeronaut. 30(2), 523–537 (2017)

Degradation of Transport Infrastructure Under Breach of Drainage: Strain and Corrosion Damage Pavlo Maruschak1(&), Andriy Sorochak1, Denys Baran1, and Olegas Prentkovskis2 1

Ternopil Ivan Pul’uj National Technical University, Ruska 56 str., Ternopil, Ukraine [email protected], [email protected], [email protected] 2 Department of Mobile Machinery and Railway Transport, Faculty of Transport Engineering, Vilnius Gediminas Technical University, Plytinės 27, 10105 Vilnius, Lithuania [email protected]

Abstract. Main damage types of transport infrastructure under breach of drainage were systematized and their causes were discovered. The causes of those failures were found mainly linked to poor drainage, traffic overloading, expansive subgrade soils, and the use of low quality materials in construction. Keywords: Degradation


Transport infrastructure
Analysis

1 Introduction We know that existing buildings and structures of Ternopil belongs to different historical periods, but most of them were constructed in Soviet times. The separation of the Soviet Union and Ukraine’s transition to a capitalist form of development caused a significant reduction of building projects financed by state funds. Major problems with maintaining the proper technical condition have arisen with objects in municipal ownership of cities and villages. Usually exploitation of such facilities takes place in violation of applicable regulatory requirements and restoring or repairing measures are insufficient. Those facilities (bridge constructions, retaining walls, stair constructions) in one way or another are exposed to the external environment. In particular on transport facilities most of reinforced concrete structures receiving damage of various degrees because of corrosion processes. Over time, these processes can lead to ultimate damage that could lead to the danger of exploitation of such facilities [1, 2]. Damaged structures and buildings should be repaired, restored or reinforced to maintain or increase their carrying capacity [3]. Sometimes during reconstruction, it is not possible to completely withdraw the facility from service. That is why very important activity is a preliminary technical diagnostics of building and establishing the causes of its damage, development of activities and technical documentation to its recovery.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 40–46, 2020. https://doi.org/10.1007/978-3-030-38666-5_5

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The aim of this work is to research the degradation processes of number of facilities in Ternopil (Ukraine) and systematization of revealed defects.

2 Research Technique Infrastructure facilities located at “Druzhba” district of Ternopil were investigated: retaining wall between Karpenko and Myru streets and stair construction, which serves as a descent from the Myru street to the Hydropark. Facilities locations marked with arrows on the district map (see Fig. 1).

Fig. 1. Investigated facilities location (Ternopil, “Druzhba” district).

2.1

Retaining Wall

Retaining walls of different types are designed for secure fixing of the soil in areas of significant level differences, i.e. serve as a protective element [4]: fixing the slopes in the area and preventing the risk of slipping of the soil. They were designed and constructed considering SNIP 2.09.03-85 (nowadays replaced with DSTU-N B.2.131:2014) “Design of retaining and basement walls”. We analyzed the structure constructed more than 50 years ago. It has as reinforcement destination as performs decorative functions. At that, the wall resists force factors only by its own geometry and weight. Conducted research found a number of damages of this retaining wall (see Fig. 2) that are systematized in Table 1.

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Retaining wall made of rubble stone and exposed to two types of loading [5]: – shear; – tipping due to horizontal pressure on its upper part and lateral surface.

Fig. 2. Types of retaining wall and asphalt damage: failure of the retaining wall fragment – a; destruction and washing out of cement mortar – b; wall surface soaking – c, d; potholes on the road passing over the retaining wall; marks see in Table 1.

It is noticeable that detected defects of the retaining wall are inherent for such loading conditions and can be attributed to the typical for this kind of structures. Moreover, violation of groundwater drainage scheme was found that eventually can

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Table 1. The main causes and types of retaining wall damage. Marking Observed damage A

Causes

Failure of the retaining wall fragment

Washout and cement adhesion violation between separate fragments of wall Destruction and washing out of cement Violation of the drainage system on the upper level of mortar between the stones of the wall retaining wall due to clogging of drainage canals that laid in the wall Drenching of separate wall fragments, Influence of snowmelt and rainwater caused by the wall profile deformation, subsidence reasons set forth in p. 2 Numerous masonry fragments falling- Influence of snowmelt and rainwater caused by out violation of asphalt on the road located at the upper level of the retaining wall

B

C D

lead to washing out the foundation and already is cause of structure partial destruction. Proper retaining wall drainage will solve this problem and its arrangement not require significant financial investments. Thus, the reconstruction of the retaining walls requires capital repair of the drainage system, which would avoid destruction of structure under the influence of rain and ground water. Moreover, a prerequisite for its successful exploitation is reconstruction of the road at the top of the retaining wall with full asphalt restoration. 2.2

Stair Construction

The built-up stair construction located at the descent from Myru Street to the Hydropark was diagnosed. A number of damages were found (see Fig. 3), including: – – – – –

stair flights offset in horizontal and vertical direction (A1); soil subsidence at horizontal stair landings (B1); destruction of horizontal protective covering slabs (C1); facing destruction (D1); ultimate corrosion of ramps for disabled people (E1).

In our opinion, the main causes of stair construction degradation are incorrect technical decisions on water removal and insufficient protection of metal parts against corrosion. Identified damage and its causes are systematized in Table 2. Table 2. The main causes and types of stair construction damage. Marking Observed damage A1, B1 C1 D1 E1

Stair flights offset

Causes

The uneven subsidence of ground base during significant structure lifetime Subsidence at horizontal Over wetting and ground base subsidence caused by the stair landings malfunction of drainage system Corrosion of concrete slabs Chemical corrosion of reinforcement bars Ramp corrosion Local corrosion damage of ramp surface

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Fig. 3. Stair construction damage: shear deformation of stair flights – a, b; subsidence – c; chemical corrosion of protective covering slabs reinforcement – d; corrosion of the ramp surface – e.

Stair flights are constructed on the concrete base over consolidated soil. It was established that due to uneven subsidence of ground base during significant structure lifetime it received noticeable cross fall. There is no danger of destruction at this stage but further process development can lead to the structure withdrawal out of exploitation. A significant subsidence and destruction of sidewalk coverage on stair landings are caused by problems in the drainage system. Snowmelt and rain water penetrating into the soil base cause it’s over wetting and significant subsidence. To prevent the development of this process it is necessary to carry out the restoration of drainage system of the stair construction.

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3 Protective Covering Slabs Destruction and Reinforcement Corrosion Numerous damage of horizontal protective plates was revealed (D1). Changes of geometry, local wall losses and destruction of the surface layer of these structural elements were established. During exploitation its structure was degraded. Under the influence of different environmental factors including water, periodical freezing and unfreezing in winter, material was partially destroyed. Significant reinforcement corrosion was revealed, which as it is known is one of the most dangerous types of reinforced concrete structures damage and causes a number of negative consequences [6, 7]: – reducing adhesion between reinforcement bars and concrete; – cracking and destruction of concrete protective layer due to the wedging impact of corrosion products; – bearing capacity reduction of structural element; – brittle fracture capability. During concrete protective covering slabs diagnosis bare reinforcement bars were found. Many outward signs of corrosion were detected: cracks in concrete protective layer along reinforcing bars, traces of rust, detachment of concrete protective layer etc. A visual inspection of the reinforcing bars in areas of concrete protective layer destruction and their fracture surface analysis were conducted. Found that the cross section of reinforcement bars has significant deviations from the original one, which is evidence of active corrosion (see Fig. 4).

Fig. 4. Cross section of degraded reinforcing bar (a) and micro mechanisms of its fracture (b–d).

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Fracture micro mechanisms of reinforcing bar are brittle, which indicates a significant material damage. At the same time, it is noticed material lamination during deformation that indicates accumulation of structural defects and weakening of grain boundaries [7]. Multiple corrosion damage were found on the ramp surfaces, some of which are crosscutting. It should be noted that in most cases they are located in areas of local deformation of the ramp material.

4 Conclusions The basic regularities of facilities degradation were established for retaining wall and stair construction. Main damage types were systematized and their causes were discovered. Obtained results will allow substantiating repair activities and the volume of necessary work. Causes and micromechanisms of corrosion damage for concrete slabs reinforcement and ramp material were analyzed.

References 1. Nicholson, A.J., Du, Z.P.: Degradable transportation systems: an integrated equilibrium model. Transp. Res. 31B, 209–223 (1997) 2. Maruschak, P.O., Konovalenko, I.V., Maruschak, O.V.: Digital image analysis of local multiple cracking zones of asphalt pavement. In: Proceedings of the 16-th International Conference “Transport Means”, Kaunas, Lithuania, 25–26 October 2012, pp. 65–68 (2012) 3. Popov, V.P., Popov, D.V., Davidenko, A.Yu.: On technology of hydraulic engineering structures retaining walls production. Procedia Eng. 111, 656–659 (2015) 4. Fishman, Yu.A.: Stability of concrete retaining structures and their interface with rock foundations. Int. J. Rock Mech. Min. Sci. 46, 957–966 (2009) 5. Ching, S., Chang, S.J.: Discrete element analysis for active and passive pressure distribution on retaining wall. Comput. Geotech. 16, 291–310 (1994) 6. Söylev, T.A., François, R.: Quality of steel-concrete interface and corrosion of reinforcing steel. Cem. Concr. Res. 33(9), 1407–1415 (2003) 7. Maruschak, P.O., Sorochak, A.P., Maruschak, O.V.: Fractodiagnostics of reasons of degradation and failure of steel water pipes. In: Proceedings of the 16-th International Conference “Transport Means”, Kaunas, Lithuania, 25–26 October 2012, pp. 183–186 (2012)

Images of Vibrations of a Passing Railway Vehicle Rafał Burdzik(&)

and Paweł Słowiński

Faculty of Transport and Aviation Engineering, Silesian University of Technology, Krasińskiego 8 str., 40-019 Katowice, Poland {Rafal.Burdzik,Pawel.Slowinski}@polsl.pl

Abstract. The paper presents the results of preliminary rail vibration tests generated by the passage of a rail vehicle. As part of the study, vibrations were recorded in three orthogonal axes, analyzing longitudinal, transversal and vertical vibrations. The results show time waveforms, signal spectra and timefrequency distributions. On the basis of the analysis of each of the forms of signal presentation, various vibration properties and interrelationships between propagation axes can be observed. Keywords: Vibration


Railway transport
Spectrogram

1 Introduction 1.1

Vibration in Railway Transport

Railway transport after many years of stagnation, and even degradation in the context of declining interest in the transport market, tries to improve its image and compete with other branches of transport. As a result, many activities aimed at improving the comprehensive rail transport system have been observed in recent years. Starting from modernization of infrastructure, production and purchase of modern rolling stock as well as improvement of traffic control systems. All this results in gradual rebuilding of the market position and increased interest in rail transport services [12, 13]. The railway is undergoing a renaissance in many countries and its ecological importance is recognized, as well as contributing to the sustainable development of the national economy [14]. Due to the technological possibilities of modern rolling stock and infrastructure, many carriers as well as infrastructure managers in particular countries modernize it to be able to use the maximum capacity of given lines, by increasing the maximum speed of moving warehouses [15]. Rail transport, although it belongs to an environmentally friendly group, generates and will generate noise and vibrations [4, 5, 16]. With the increase of the speed of trains and the frequency of their running, this problem can be significant. An important aspect is also the characteristics of urban agglomerations, where the development is characterized by linearity or location along the railway lines. The path of propagation of vibrations in the ground, for any geological substrate, at any distance from the reference measurement point, in which vibrations were recorded, taking into account the geometric damping and soil absorption index, the approximate amplitude of the © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 47–56, 2020. https://doi.org/10.1007/978-3-030-38666-5_6

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vibration wave can be determined [10]. For this purpose, a simplified dependence describing the absorption of surface waves is used [3]:
ar ¼ a0

r0 ri

w

eaðrr r0 Þ ;

ð1Þ

where a0 – vibration amplitude at the reference measuring point; r0 – distance of the reference point from the vibration source; ar – amplitude of vibrations intended at point i; rr – distance of the reference point from the vibration source; w – coefficient of geometric damping and soil absorption; a – coefficient defining the type of geological substrate. It is important to reduce the negative impact and counteract the phenomena of excessive vibration and noise. An important analysis in this respect is the mechanisms of generating and occurrence of these phenomena. It is additionally very important to correctly identify the propagation of vibration and acoustic waves generated by moving rail vehicles. Figure 1 shows a general scheme of propagation of vibrations and noise in the immediate vicinity of railway infrastructure.

Fig. 1. Ground borne vibrations modelling [7].

The development and availability of advanced computing devices has enabled the development of mathematical models describing the phenomena of railway vibration and noise generation. Increasingly, the level of complexity of these models makes their correct application and correct interpretation of results difficult [17, 18]. Therefore, the area of measurement of these quantities should be developed in order to broaden empirical knowledge and the possibility of verification of theoretical models. In this approach, the analysis of the capacity of the information of vibroacoustic signals is important. Due to the non-preferential characteristics of these signals, it is advisable to observe changes in the time and frequency domains [19]. The article presents exemplary results of a comprehensive analysis of changes in vibration signals in the field of time, frequency and using synchronous time-frequency distributions.

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1.2

49

Sources of Noise and Vibration of Rail Vehicle

According to [3], vibrations originating from means of transport affecting the environment most often belong to the group of paraseismic vibrations of a random and nonexistent nature. This is due to the variety of simultaneous sources of vibrations. One of the significant sources of vibrations in rail vehicles is the variable forces created in the wheel-rail contact zone. Variable distribution of these dynamic forces is the result of geometrical inequalities of the track, characteristics and vulnerability of railway sleepers, elastic properties of the rails themselves and dynamic interaction as a result of the movement of the rail vehicle [3]. The publication [1] presents the “TWINS” (Track-Wheel Interaction Noise Software) model of vibration generation in the wheel-rail contact area (Fig. 2). This model is a development of Remington’s work from the 70s.

Fig. 2. Model for rolling noise generation [1].

The highest amplitudes of vibrations occur in the resonance area, when the frequency of excitations is close to the natural frequency of the rail vehicle track system [6]. In this case, it is important to analyze both the own frequencies of the rails (tracks) and the resonant frequencies of unsprung masses of suspension of rocking vehicles.

Fig. 3. Schematic diagram of rolling noise generation by the wheel/rail interaction [8].

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The sources of noise of a moving train are also wheel contact phenomena, but also aerodynamic resistance. In both cases, the noise increases with increasing driving speed [20–23]. Wheel-rail interaction and dynamic forces, generate rail vibration and rolling noise. The above mechanisms have been presented in the form of a general scheme in Fig. 3 [8].

2 Research Methodology The defined research problem was the analysis of synchronous vibroacoustic images as instantaneous sets of vibration signals and acoustic pressure. The aim of the presented research was to assess the information capacity of the rail vibration signals recorded in three wave propagation directions: longitudinal, transverse and vertical. Signal registration was performed in the LabVIEW environment. The measurement system used for this study included: – 3 accelerometers with sensitivity 100 mV/g; – data acquisition unit (DAQ) with signal conditioner, 24 bit; – computer with software (Fig. 4).

Fig. 4. DAQ system components and transfer [11].

Accelerometers are attached to the rail by means of a handle in three axes X, Y, Z, where X axis (along the axis of the track), Y axis (transverse to the axis of the track), Z axis (vertically to the axis of the track). In addition, during the preliminary verification tests, vibration signals were recorded using a 3-axis sensor glued directly to the rail near the measuring holder. This was to control the combination of signals recorded on the holder and directly on the bus. The mounting bracket and sensors installed during measurements are shown in Fig. 5.

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Fig. 5. Mounting bracket and sensors installed during measurements.

3 Analysis of Results The paper presents results of vibration signals acquired during passage of electric multiple unit ELF 2. The name Elf is acronym of electric low floor. It is an electric multiple unit developed by Polish rolling-stock manufacturer Pesa SA. The tested train is a 34WEa model, i.e. a 2-unit vehicle equipped with 4 motors with 400 kW power with the Bo‘2’Bo axis system, which means two two-axle bogies with an individual drive and one rolling trolley. The PESA trolley is 27MNd with 2.7 m spacing, and the intermediate PESA 40A trolley with 3 m wheelbase. The service weight is 83.2 t, length 42.65 m. All these construction parameters affect the image of vibration signals, due to the distance (time) of subsequent impulses and dynamic forces proportional to the mass [24, 25].

Fig. 6. Acceleration of vibration signals in the observation window: X axis red, Y axis blue, Z axis orange.

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In order to comprehensively observe the signals and evaluate the information capacity, time courses were presented in the X, Y and Z measuring axes. Figure 6 shows the observation window, i.e. vibration signals recorded directly during the passage of the train in three orthogonal axes. After applying three runs on each other, the highest amplitude of vibrations in the Y axis, i.e. in the transverse direction to the track axis, where the amplitude of vibration exceeded the recorded range was noted. Then the signal spectra were calculated to analyze the frequency distribution. For this purpose, the converted data from the LabView program to the data format in Matlab. The analysis of signal spectra makes it possible to evaluate the dynamics of vibrations and identify the dominant frequency components (Fig. 7) [2]. The presented example shows a slight similarity in the dynamics of longitudinal and vertical waves, whereby the Z axis oscillation signal is characterized by a greater number of frequency components, which causes that their amplitudes are smaller at a comparable value of the total signal energy with vibrations on the X axis. Monotonicity of the frequency components was observed for the transverse wave, which cumulate around 1,000 Hz. In this case, the local maximum of Y axis oscillation is by far the largest compared to the X and Z axes.

Fig. 7. Spectrums of the signals (units: Hz, ms−2): (a) longitudinal vibrations (X axis); (b) transverse vibrations (Y axis); (c) vertical vibrations (Z axis).

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Due to the non-stationary character of the signals, they were transformed into time and frequency domains. This makes it possible to analyze signal changes over time for subsequent frequency components. For this purpose, signal spectrograms have been calculated, which can be described as scalar products of a signal with window g modulated frequency n [9]: Z cn;t0 ¼

sðtÞgðt  t0 Þeint dt;

ð2Þ

Based on the analysis of the spectrogram of longitudinal vibrations (X axis, Fig. 8), signal gain can be observed in the frequency band from a few hundred Herzs to approx. 7 kHz. The biggest amplification occurs in the range from a few Hz to about 4 kHz during the passage of the composition, which has been taking place for 30 s. At the same time, the maximum signal energy is definitely around 1 kHz.

Fig. 8. Spectrogram of longitudinal vibrations (X axis).

The analysis of t-f representation of transverse vibration (Y axis, Fig. 9) reveals a clear accumulation of signal energy at a frequency of about 1 kHz. The signal frequency path is visible in the 30–34 s window, almost in the entire frequency range, however their amplification is small except for frequencies of about 1, 2 and 4 kHz. Time-frequency distribution of vertical vibration (Z axis, Fig. 10) is similar to the X-axis oscillation spectrogram. However, it can be noticed that the signal gain in the whole band up to 5 kHz is greater than for the vibrations recorded on the X and Y axis. As in Fig. 8, the excitation of the largest number of frequencies occurs in the following seconds in the range of 30–34 s.

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Fig. 9. Spectrogram of transverse vibrations (Y axis).

Fig. 10. Spectrogram of vertical vibrations (Z axis).

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4 Summary The paper presents the results of preliminary tests of rail vibrations forced by the passage of a rail vehicle. For a comprehensive analysis, vibrations were recorded in three perpendicular axes: along the rail axis, perpendicular and vertical. The analysis was carried out in the domain of time as a distribution of vibration accelerations in the subsequent seasons of registration, which makes it possible to identify the observation window. Additionally, in order to analyze the dynamics of the signal, frequency spectra have been determined that allow the assessment of frequency components. Due to the fact that the recorded signals belong to the group of non-stationary signals, they were also transformed into the t-f representation by calculating the spectrograms. Thanks to this, you can observe the time distribution for specific frequency bands. A comprehensive comparison of the results obtained allows the observation of vibroacoustic images, which can be treated as a trace and signature of a passing train. Consequently, a set of data is obtained, which can be analyzed according to various criteria, including the assessment of the impact of vibrations and noise by means of transport.

References 1. Thompson, D.: Railway noise and vibration: the use of appropriate models to solve practical problems. In: The 21st International Congress on Sound and Vibration, Beijing, China, 13– 17 July 2014 (2014) 2. Lyons, R.: Introduction to Digital Signal Processing. WKŁ, Warszawa (2006). (in Polish) 3. Nader, M.: Vibrations and noise in transport - selected issues. Oficyna Wydawnicza Politechniki Warszawskiej, Warszawa (2016) 4. Burdzik, R., Konieczny, Ł., Deuszkiewicz, P., Vaskova, I.: Application of time-frequency method for research on influence of locomotive wheel slip on vibration. J. VibroEng. 20(8), 2998–3008 (2018) 5. Burdzik, R., Słowiński, P., Juzek, M., Nowak, B., Rozmus, J.: Dependence of damage to the running surface of the railway rail on the vibroacoustic signal of a passing passenger train. Vibroeng. Procedia 19, 226–229 (2018) 6. Chromański, W.: Simulation and optimization in the dynamics of rail vehicles. Oficyna Wydawnicza Politechniki Warszawskiej, p. 141 (1999) 7. University of Edinburgh Homepage. https://www.eng.ed.ac.uk/research/themes/railwayengineering. Accessed 08 Feb 2019 8. Thompson, D.J., Jones, C.J.C.: A review of the modelling of wheel/rail noise generation. J. Sound Vib. 231(3), 519–536 (2000) 9. Durka, P.J.: Between time and frequency: elements of contemporary signal analysis. Wydział Fizyki Uniwersytetu Warszawskiego (2004) 10. Cisielski, R., Maciąg, E.: Road vibrations and their impact on buildings. Wydawnictwo Komunikacji i Łączności, Warszawa, p. 248 (1990) 11. NI Homepage. http://www.ni.com/data-acquisition/what-is/. Accessed 08 Feb 2019 12. Jacyna, M., Wasiak, M., Lewczuk, K., Kłodawski, M.: Simulation model of transport system of Poland as a tool for developing sustainable transport. Arch. Transp. 31, 23–35 (2014) 13. Siergiejczyk, M., Pas, J., Rosinski, A.: Issue of reliability–exploitation evaluation of electronic transport systems used in the railway environment with consideration of electromagnetic interference. IET Intel. Transport Syst. 10(9), 587–593 (2016)

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14. Fedorczak-Cisak, M., Furtak, M., Gintowt, J., Kowalska-Koczwara, A., Pachla, F., Stypuła, K., Tatara, T.: Thermal and vibration comfort analysis of a nearly zero-energy building in Poland. Sustainability 10(10), 3774 (2018) 15. Burdzik, R., Nowak, B.: Identification of the vibration environment of railway infrastructure. Procedia Eng. 187, 556–561 (2017) 16. Nowakowski, T., Komorski, P., Tomaszewski, F.: The efficiency of tram articulations compared to vibroacoustic emissions. Arch. Transp. 44, 55–63 (2017) 17. Chilinski, B., Zawisza, M.: Analysis of bending and angular vibration of the crankshaft with a torsional vibrations damper. J. VibroEng. 18(8), 5353–5363 (2016) 18. Burdzik, R., Wegrzyn, T., Lisiecki, A.: Research on influence of fatigue metal damage of the inner race of bearing on vibration in different frequencies. Arch. Metall. Mater. 59(4), 1275– 1281 (2014) 19. Burdzik, R.: Novel method for research on exposure to nonlinear vibration transferred by suspension of vehicle. Int. J. Non-Linear Mech. 91, 170–180 (2017) 20. Ortiz, J.O., Betancur, G.R., Gomez, J., et al.: Detection of structural damage and estimation of reliability using a multidimensional monitoring approach. Proc. Inst. Mech. Eng. Part F J. Rail Rapid Transit 232(4), 1021–1032 (2018) 21. Gutierrez-Carvajal, R.E., Betancur, G.R., Castaneda, L.F., et al.: A fractional Fourier transform-based method to detect impacts between the bogie and the car body of a railway vehicle: a data-driven approach. Proc. Inst. Mech. Eng. Part F J. Rail Rapid Transit 232(1), 288–296 (2018) 22. Gutierrez-Carvajal, R.E., Betancur, G.R., Barbosa, J., et al.: Full scale fatigue test performed to the bolster beam of a railway vehicle. Int. J. Interact. Des. Manuf. IJIDEM 12(1), 253–261 (2018) 23. Sawczuk, W., Tomaszewski, F.: Evaluation of the wear of friction pads railway disc brake using selected frequency characteristic of vibrations signal generated by the disc brake. Diagnostyka 14(3), 69–74 (2013) 24. Myamlin, S., Lingaitis, L.P., Dailydka, S., Vaičiūnas, G., Bogdevičius, M., Bureika, G.: Determination of the dynamic characteristics of freight wagons with various bogie. Transport 30(1), 88–92 (2015) 25. Jurevičius, M., Turla, V., Bureika, G., Kilikevičius, A.: Effect of external excitation on dynamic characteristics of vibration isolating table. Eksploatacja i Niezawodność 17(2), 260–265 (2015)

Application of Modern Monitoring Measures in Lithuanian Dangerous Cargo Transportation Erikas Mazėtis(&) and Nijolė Batarlienė Vilnius Gediminas Technical University, Plytinės str. 27, 10105 Vilnius, Lithuania [email protected], [email protected]

Abstract. Lithuanian territory carrying thousands of tons of dangerous materials within the country and international routes. In case of hazardous and accident situations, the transport control and assistance services do not have much information - they lack knowledge of the nature and characteristics of the dangerous goods being transported, as well as their impact and risk. The paper presents the technologies used to monitor dangerous goods for locating a cargo area, presenting status parameters and other necessary information. It examines the main tools and products used for monitoring dangerous goods in Lithuania, as well as their most important functions. A survey was carried out to identify the most important monitoring tools and the most important functions of the monitoring of dangerous goods by road. Estimated Kendal’s match factors when there are no related ratings. Research has shown that the most important monitoring functions are real-time cargo handling, fast transfer of necessary information to drivers, real-time recording of cargo condition (changes, temperature). Keywords: Dangerous goods


Monitoring
Modern measures

1 Introduction Dangerous freight – is a hazardous substance that is defined by the Dangerous Substances Act, to be dangerous [5]. Dangerous goods are classified on the basis of immediate physical or chemical effects that may impact on people, property or the environment – explosive, flammable, corrosive, chemically reactive, highly combustible, acutely toxic, radioactive or infectious. Various types of cargo are transported by road, with an annual increase in the volume of cargo transported, from industrial goods to non-standard cargo. Such cargoes are described as dangerous and are usually liquid (petroleum products), gaseous (gas), various chemicals, radioactive materials. Dangerous goods are subject to restrictions, additional documentation, control, safety measures are needed, which makes the complexity of organization of the transport process more difficult [6]. As far as vehicles carrying dangerous goods are concerned, they are treated in the same way as every other vehicle and do not have special safety conditions [2].

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However, the safety of both the dangerous goods and the vehicle transporting them must be ensured, as people and the environment would suffer negative consequences in the event of an accident. For the control and monitoring transport of dangerous goods by road, it is necessary to prepare for its transportation, to follow the movement of cargo, to regularly check the condition of cargo and vehicle, to be able to assess the emerging risks and safety aspects. In the event of dangerous and accident situations, the authorities do not have much information – they lack knowledge of the nature and characteristics of the goods transported, as well as their impact and risks. The services must rely only on minimal knowledge of the dangerous goods, which can lead to inappropriate elimination of the consequences or damage to the environment and the surrounding environment. The aim of the article is to analyze monitoring technologies of dangerous goods, to identify the modern measures of transport monitoring, to perform analysis of them used in Lithuania, to investigate what functions of monitoring measures are considered to be most important. It was calculated the Kendall Concordance coefficient when there are no related rankings. The lowest value of the Concordation coefficient Wmin is also calculated, with which it can be stated that expert opinions are considered to be harmonized.

2 Measures for Monitoring of Dangerous Goods Freight monitoring services, which can be used to ensure cargo safety during transportation or monitor its condition parameters or to control the direction of movement, by means of tracking tools, are increasingly included in the services provided by the carrier. Cargo monitoring is particularly important for the transport of dangerous goods, because by using the tools necessary for monitoring, it is possible to foresee a potential danger, give instructions to drivers in a timely manner, ensure a safe journey of the vehicle. Ensuring safety and developing risk management strategies as a preventive measure to mitigate the potential consequences of transporting dangerous goods is essential, but Laarabi and others [9] say that there is no unified risk management model on an international scale. The authors believe that this issue will be resolved in the future, as research is already underway, advanced technologies are being developed, and the need for managing dangerous goods is emerging. One of the most commonly used tools is GPS systems. It allows the tracking of various objects, vehicles with their exact geographical location [3]. GPS systems for transporting dangerous goods allow to determine how the transport plan is complied with, as well as the amount of hazardous materials in the vehicle if it is equipped with special sensors. Systems can also be useful in choosing an efficient route for transporting hazardous materials, bypassing densely populated areas and other locations. Dangerous goods transport involves complex technical and hazard reduction issues; thus GPS systems need to provide quality information. Hong and others [7] argue that this is not always the case, because the positioning gaps in the interface between GPS data points and road maps, as well as data collection constraints, create uncertainty of true positioning [7]. This is manifested by inaccurate system reporting of the system, for example,

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without updating the data on new roads built and other infrastructure. The operation of GPS system is based on GSM/GPRS or WIFI communication, which remotely or wirelessly transmits data from the vehicle to the facilities where the transport and other procedures related to the carriage are monitored. According to Laarabi and others [9] GPRS-based data transmission is widely used for real-time monitoring of various remote objects (such as vehicles) and their status, and the main purpose is to secure security, collect information, improve service quality for strategic purposes, tactical or operational solutions. In practice, a GPRS-enabled GPS system can transmit a large amount of data [1], thus not only the location of the area that could be tracked during the transportation of dangerous goods, but also additional measures to improve the quality of cargo monitoring. Various sensors and other measuring instruments are used for this purpose, which analyze the condition of the vehicle and the load in real time and transmit the necessary information to the central carrier database via GPRS. With the help of the sensors, the vehicle is widely monitored – speed, distance traveled, technical parameters. These measures can be used to transport dangerous goods in tanks when it is necessary to carefully monitor the transport. Dangerous goods vehicles are increasingly equipped with emergency buttons that allow emergency rescue services to be automatically informed of an imminent disaster. All vehicle sensors are connected by a single on-board unit that sends the stored messages and parameters to the carrier’s data server and saves them. The widespread transportation by container also drives attention to the transportation of dangerous goods, as this transport capacity combines road, rail and water transport [11]. When intermodal transport modes change, dangerous goods remain in containers, so each operator must monitor the condition of the cargo being transported. For this purpose, Ding and others [4] distinguish the Internet of Things technology. According to the author, it combines various technologies for gathering, analyzing and forwarding information such as RFID, GPS, laser, infrared sensors. Connected devices and objects are able to communicate with each other, automatically recognize and send information about the object being monitored to the database via the Internet. The importance of sensors in containers was also examined by Xu with other authors [15] who emphasized the arrangement of different types of sensors to specifically know the information on humidity, temperature, vibration or gas leakage. To accurately determine humidity, vibrations, etc. the size of the container must be taken into account. 40-ft containers are commonly used in logistics, so there should be more sensors in doors, side walls, ceilings, rear walls. Sensor work in containers is based on sensorgathered information that is systematized and remotely transmitted via GPS, 4G, 5G or GPRS to the monitoring platform. In this case, the carrier or other users may connect to this platform during the transport of the dangerous goods and monitor the condition of the container in real time. Pirník, together with other authors [12], is investigating the problem of modern dangerous cargo monitoring. According to them, the main lack of monitoring is also the frequent absence of direct information on the location of dangerous goods. The authors mention the co-operation between the transport of dangerous substances and the safety authorities and highlight the need for the use of Intelligent Transport Systems (ITS). ITS can be understood as a system of application of various information and

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communication technologies in the field of transport. It manifests itself in the rapid and accurate exchange of data between vehicles, road infrastructure equipment and passenger communication tools [10]. According to Pirník [12], the goal of ITS is to optimize and regulate road transport flows, mobility, transport safety, addressing transport, public transport or environmental issues. ITS systems are integrated into the road infrastructure, thus, according to the author, vehicles carrying dangerous goods with the required load sensors could interact with special infrastructure equipment, such as equipment at border crossings or national and international highways. This would provide important information to the relevant authorities and ensure efficient freight tracking and emergency assistance. In addition to GPS systems, RFID technologies are actively used to monitor the transport of dangerous goods. If a liquid or gaseous cargo is transported, then a variety of vehicle sensors is sufficient to monitor the transport, but it is not enough to carry the loads contained in the packages, so in this situation the most appropriate way is to choose RFID technology equipment. RFID is an object tagging and tracking technology that helps manage inventory and promotes supply chain efficiency, radically changes business and consumer relationships [14], is able to determine the exact location of an object, protects information about an object [13], allows you to determine not only the abstract product type, but also provides the exact specification [8]. The operation of the RFID system is ensured by recording and retrieving the information contained in the RFID tag during the use of the radio frequency signal. The system consists of an RFID tag (chip), an RFID reader and software. All the necessary cargo information (names, address of consignor and consignee, quantity, instructions on handling the goods during transportation and incidents) is stored in the RFID tag before transportation. Tags can be of two types - active (using their own power source) and passive (receiving energy from the reader’s signal). The RFID system can exchange available information with both the parent carrier database and the freight driver via the mobile terminal. If the load is damaged or deformed during transportation, the information immediately reaches all the participants in the system. In this way, the safety aspects of the dangerous goods transport can be ensured, the exact location of the cargo, the emergency authorities are informed in a timely manner and it does not take much time to explain the potential threat, as all the necessary data are provided instantly.

3 Investigations of Monitoring Measures Used in Lithuania 3.1

Method

An expert survey was conducted to find out the main monitoring measures used by various road haulage companies in Lithuania. Experts selected to carry out the research in the field of transport of dangerous goods have been selected for a minimum of 5 years. This target group has been selected as the most appropriate to specify the main monitoring measures currently used in the dangerous goods transport market. 24 dangerous freight transport specialists participated in the expert survey.

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Summarizing the results, it can be stated that monitoring of the dangerous goods transport market is mainly carried out with the help of GPS tracking devices. With these measures, proper customer service and accurate cargo information is ensured. According to experts, GPS tracking systems help to control compliance with work and driving time rules, control fuel consumption, monitor real-life hazardous cargo parameters. Slightly less vehicles use different temperature sensors. According to experts, these devices are more suitable for use in liquid or other sensitive materials for chemical or physical processes (see Fig. 1).

Sensors for detecƟng changes of cargo

6

Cargo temperature sensors

7

Cameras inside/outside vehicle

1

Real Ɵme GPS Tracking systems

10 0

2

4

6

8

10

12

Fig. 1. Expert opinions on the most used dangerous cargo tracking systems in Lithuania.

The same applies to cargo physical change detecting sensors. In order to integrate them into a common monitoring system, there is a need for additional intellectual infrastructure and technical solutions that are often reluctant for a smaller transport company to take on financial grounds. According to experts, the monitoring of the camera’s exterior and interior is rarely used, although it helps to protect against vehicle damage, theft and so on. The expert survey carried out showed that the most frequently used GPS technologies for transporting dangerous goods by road are in Lithuania. Currently, the market offers a wide range of tracking and tracing products. Companies can select telematics products such as Ecofleet, Ruptela, Transics, Wialon, BCE, Fleetboard, Loctracker, Mapon, Sycada, Totemas for tracking dangerous goods and etc. Ecofleet, Ruptela and Totemas are often used not only in Lithuanian companies, but also in foreign transport companies. The popularity of the products is due to the ability to control the fleet of vehicles, fuel control, automated accounting, fast recording of tachograph data and contact with drivers, without the main tracking function, to ensure safety (trailer door sensors, remote engine blocking), monitor cargo temperature and other settings. Due to the abovementioned possibilities, more efficient and safer transportation of dangerous goods is organized – the exact location, condition of the cargo is known, fuel costs are reduced, the working time of the drivers is effectively used and the risk is reduced.

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Results and Discussion

The experts were asked to fill in a table according to a ten-point system to assess the most important functions for monitoring dangerous goods. The scores obtained for the ten functions were summed up. An alphabetical letter is assigned to each monitoring function to provide correct statistics: • • • • • • • • • •

A – Real-time load motion detection, B – Real-time load status recording, C – Individual cargo (static, pallet) tracking, D – Vehicle tracking, E – Vehicle tracking with sensors, F – Fast cargo information transfer to database, G – fast forwarding of information to drivers, H – protection against theft and burglary, I – possibility to predict accident and incident scenario, J – possibility to evaluate main risk factors.

Calculations have shown that the assessment of the 10 most important monitoring measures of 24 respondents in the transport of dangerous goods by road, the respondents’ opinions overlap, and the opinion of all respondents is summarized. It was calculated the Kendall Concordance coefficient when there are no related rankings.
j for each criterion are further calculated. The averages of the rankings R P10
1 ¼ i¼1 Rij ¼ 14 ¼ 1;4; Criterion A rank average: R 10 P1010 Rij 36 i¼1
2 ¼ Criterion B rank average: R ¼ 10 ¼ 3;6; P10 10
3 ¼ i¼1 Rij ¼ 88 ¼ 8;8; etc. Criterion C rank average: R 10 10 Summing up the averages of all grades, 55 is the sum of the significance factor. In addition, the difference between the rank amounts and the constant size was calculated, as well as the number of rank amounts and squares of a constant size. P Criterion A difference: ni¼1 Rij  12 nðm þ 1Þ ¼ 14  10ð102 þ 1Þ ¼ 41; P Criterion B difference: ni¼1 Rij  12 nðm þ 1Þ ¼ 36  10ð102 þ 1Þ ¼ 19; P Criterion C difference: ni¼1 Rij  12 nðm þ 1Þ ¼ 88  10ð102 þ 1Þ ¼ 33; etc. The number of rank amounts and the constant-sized squares are calculated. Square of Criterion A difference: X n

2 1 n ð m þ 1 Þ R  ¼ ½14  552 ¼ ½412 ¼ 1681: i¼1 ij 2

ð1Þ

Differences in remaining criteria are calculated using the same methodology. After calculating the squares, the next step is to calculate the Kendall concordance coefficient when there are no related rankings.

Application of Modern Monitoring Measures

W¼

12S 12  5296 ¼ ¼ 0;642; n2 ðm3  mÞ 102 ð103  10Þ

63

ð2Þ

the number obtained is greater than 0.5, so it can be said that the respondents’ opinions are harmonized. Number of monitoring features and security factors m > 7, there are no associated values, thus the weight of concordance coefficient is calculated and a random size is found. v2 ¼

12S 12  5296 ¼ ¼ 57;77: nmðm þ 1Þ 10  10ð10 þ 1Þ

ð3Þ

Then number of degrees of freedom is determined v = m − 1 = 10 − 1 = 9, the significance level is selected a = 0,01, thus critical value v2kr ¼ v2v;a ¼ 21;66: The estimated v2 value 57,77 is higher than the critical value v2kr (21,66), thus the expert opinion is considered to be harmonized, and the average rank shows the overall opinion. The lowest value of the Concordation coefficient Wmin is also calculated, with which it can be stated that expert opinions are considered to be harmonized. Wmin ¼

v2v;a 21;66 ¼ 0;241  0;642: ¼ nðm  1Þ 10ð10  1Þ

ð4Þ

Estimated average grades of monitoring measures have shown that criterion A (real-time load detection) is more important than the rest. In order to determine more precisely each factor is more important than the other, additional calculations were made to calculate the correlations of the criteria
qj , their reverse sizes dj and the importance indicators Qj. Criterion A correlation is calculated: R1
q1 ¼ Pm j¼1

Rj

¼

1; 4 ¼ 0;025: 55

ð5Þ

Criterion A correlation reverse size: d1 ¼ 1 
q1 ¼ 1  0;025 ¼ 0;975:

ð6Þ

Criterion A importance indicator is calculated by dividing the reverse size by the sum of all criteria m − 1: dj Qj ¼ Pm

j¼1 dj

¼

dj 0;975 ¼ 0;108: ¼ 9 m1

ð7Þ

On the same principle, correlations of the remaining criteria, their inverse values, weight are calculated. The results are shown in Table 1 and Fig. 2.

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E. Mazėtis and N. Batarlienė Table 1. Evaluation of criteria for importance of monitoring functions.

Indicator mark

Symbol of monitoring function A B C D E

F

G

H

I

J


qj dj Qj
j Q Placement of criteria by importance

0.025 0.975 0.108 0.175

0.065 0.935 0.104 0.135

0.160 0.840 0.093 0.040

0.155 0.845 0.094 0.045

0.118 0.882 0.098 0.082

0.091 0.909 0.101 0.109

0.051 0.949 0.105 0.149

0.091 0.909 0.101 0.109

0.109 0.891 0.099 0.091

0.135 0.865 0.096 0.065

1

3

10

9

7

4

2

5

6

8

Figure 2 shows the main monitoring functions by ranking method.

Fig. 2. Monitoring functions by ranking method.

In summary, the most important function of monitoring dangerous goods is the real-time movement of cargo. Other key features include fast transfer of required information to drivers, real-time recording of cargo status (temperature and changes). The least important functions were the tracking of individual cargo units (pallets, structures, etc.), vehicle tracking by cameras.

4 Conclusions 1. The main technologies used to organize the monitoring of dangerous goods and to carry out real-time monitoring are GPS tracking, RFID tagging and tracking, vehicle condition and cargo parameter sensors, Internet of Things. GPS tracking measures allow to determine the exact location of the load and the vehicle, as well as to control various parameters related to the load temperature and other status aspects. 2. RFID technology may be used to mark dangerous goods during which all the necessary information is transferred to a special tag that records the changes occurring during transport and transmits information to the databases.

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3. The Internet of Things technology allows tracking of container locations, forecasting arrival and unloading times, recognizing the type of cargo being carried and can be used not only during transport but also to ensure the smooth operation of the container terminal. 4. The expert survey carried out showed that in Lithuania, GPS technologies are used for the monitoring of dangerous goods transport by road. 5. Due to the supply of large cargo monitoring products and their functional capabilities, companies can not only track vehicles, but also monitor cargo condition, fuel consumption, drivers’ working time, vehicle safety, and manage the fleet. 6. Qualitative research has shown that the most important monitoring functions are real-time cargo handling, fast transfer of necessary information to drivers, real-time recording of cargo condition (changes, temperature).

References 1. Aydin, G., Qi, Z., Pierce, M., Fox, G., Bock, Y.: Architecture, performance, and scalability of a real-time global positioning system data grid. Phys. Earth Planet. Inter. 163(1–4), 347– 359 (2007) 2. Batarlienė, N.: Pavojingųjų krovinių vežimo pagrindai. Technika, Vilnius (2007) 3. Boulmakoul, A., Laurini, R., Zeitouni, F.: Spatial monitoring and routing system for the transportation of hazardous materials. In: Rautenstrauch, C., Patig, S. (eds.) Environmental Information Systems in Industry and Public Administration, pp. 227–236. IGI Global, Hershey (2001) 4. Ding, L., Chen, Y., Li, J.: Monitoring dangerous goods in container yard using the Internet of Things. Sci. Program. 1–12 (2016) 5. European Agreement concerning the International Carriage of Dangerous goods by road (ADR) and protocol of signature. United Nations, New York and Geneva, Volume I, II (2017) 6. European road safety action programme mid-term review. Communication form the Commission. Brussels, 22/02/2006 COM 74 final (2006) 7. Hong, S., Heo, J., Vonderohe, A.P.: Simulation-based approach for uncertainty assessment: integrating GPS and GIS. Transp. Res. Part C Emerg. Technol. 36, 125–137 (2013) 8. Juban, R.L., David, C.W.: Would you like chips with that? Consumer perspectives of RFID. Manage. Res. News 27(11/12), 29–44 (2004) 9. Laarabi, M.H., Boulmakoul, A., Sacile, R., Garbolino, E.: A scalable communication middleware for real-time data collection of dangerous goods vehicle activities. Transp. Res. Part C 48, 404–417 (2014). https://doi.org/10.1016/j.trc.2014.09.006 10. Lacey, D.: Vehicle-to-Vehicle Technologies for Intelligent Transportation Systems: Development, Challenges and Security Proposals. Nova Science Publishers, New York (2014) 11. Monios, J.: Institutional Challenges to Intermodal Transport and Logistics: Governance in Port Regionalisation and Hinterland Integration. Transport and Mobility Series. Routledge, Farnham (2014) 12. Pirník, R., Spalek, J., Halgaš, J.: Monitoring dangerous cargo via satellite toll systems. Ann. Fac. Eng. Hunedoara Int. J. Eng. 13(2), 241–244 (2015) 13. Roberts, C.M.: Radio Frequency Identification (RFID). Comput. Secur. 25, 18–26 (2006)

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14. Turri, A.M., Smith, R.J., Kopp, S.W.: Privacy and RFID technology: a review of regulatory efforts. J. Consum. Aff. 51(2), 329–354 (2006) 15. Xu, S., Zhang, S., Cao, W.: Study on the multi-sensors monitoring and information fusion technology of dangerous cargo container. In: AIP Conference Proceedings, vol. 1890, no. 1, pp. 1–5 (2017)

User Acceptance of Driverless Public Transportation: A Questionnaire-Based Study in Budapest Mohammad Maghrour Zefreh(&)

and Adam Torok

Budapest University of Technology and Economics, Budapest 1111, Hungary [email protected], [email protected]

Abstract. The modern transportation system is walking step by step toward automation. As automated technology continues to develop, the new technology offers a considerable opportunity to enhance public transportation systems especially in the development and promotion of the sustainable mobility concepts. The driverless public transportation can only become a reality if they are fully accepted by their target/potential users. Hence, user acceptance studies are of great importance since they will investigate what factors can influence this acceptance. In the current study, the relationship between acceptance of driverless public transportation (PT) and PT passengers’ personal characteristics has been examined using Fisher’s Exact Test. The results showed that the user acceptance of driverless PT has a significant relationship with the health condition of the passengers, frequency of PT usage, age, level of education and the motivation of the trip made by public transportation. Keywords: User acceptance


Driverless technology
Public transportation

1 Introduction Self-driving vehicle technology has the potential to bring lots of benefits to the transportation system. Though the potential benefits for private vehicles have attracted significant research attention, the new technology also offers great opportunity to enhance public transportation systems [1–3]. Public transportation is a crucial part of urban mobility that should be fully paid attention since it has a great role in reducing congestion in the cities [4, 5]. Furthermore, the so-called automated public transport offers great potential for the development and promotion of sustainable mobility concepts [6]. At the moment, there are some available automated public transportations in the world (e.g. in Sion, Lyon, Michigan, Frankfurt, Paris, Vancouver) [6, 7]. Furthermore, in Europe there are some projects seeking for feasibility of automated public transportation. For instance, CityMobil2 Automated Road Transport Systems, Funded as part of the European Commission’s Seventh Framework Program. The main aim of this project was to test the feasibility of such vehicles in providing an alternative public transport option to urban environments across Europe [8].

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Apart from the issues related to the technical feasibility, ethical and legal aspects [9], driverless public transportation (taking all means of public transportation into account) can only become a reality if they are fully accepted by their target/potential users. 1.1

User’s Acceptance of Technology

Technology Acceptance Model (TAM) is one of the most widely cited theoretical models that has been developed to explain users’ acceptance of technology [10]. In this framework, “ease of use” and “perceived usefulness” are considered to be the two most important factors that influence the user’s decision in technology use. The TAM has been continuously expanded since TAM is capable of being extended to include additional external variables. Unified Theory of Acceptance and Use of Technology (UTAUT) is an extension of TAM formulated by Venkatesh et al. [11] that aims to explain user intentions in acceptance of technology. UTAUT has four key constructs (i.e., performance expectancy, effort expectancy, social influence, and facilitating conditions) that influence behavioral intention to technology use. According to [11], performance expectancy, effort expectancy and social influence are direct determinants to influence behavioral intention to use a technology, while facilitating conditions determine technology use. Also, individual variables including age, gender, experience and voluntariness of use are considered to be the moderators of the impacts of these four key constructs on usage intention and behavior. The UTAUT were further extended in UTAUT2 [12] in which three constructs were added to UTAUT model, namely hedonic motivation, price value and habit. Figure 1 shows the proposed UTAUT2 [12].

Fig. 1. UTAUT2 model [12].

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In 2017, Madigan et al. expressed the importance of user acceptance studies for automated transportation systems in order to provide a viable alternative to other modes of transport, and for their value to be recognized by public organizations investing in such systems [13]. In the area of automated transportation system, literature mainly considered a limited number of moderators (e.g. age and gender) of the relationship between the main model variables (e.g. performance expectancy, effort expectancy, social influence facilitating conditions, hedonic motivation [12]) that influence consumer behavioral intentions towards automated transportation system [6, 13]. However, the present research work is, seeking for the other potential important users’ characteristics (passengers’ characteristics in public transportation domain) that might influence on their technology acceptance to be considered either as new moderators of the model or even a new model variable for the possible potential Budapest driverless public transportation user acceptance model. The reminder of this paper is organized as follows. In Sect. 2, the hypotheses have been formulated followed by a short description about the collected passenger’s personal characteristics. In Sect. 3, the results of the Fisher’s Exact Test have been presented and discussed. Finally the paper has been concluded in Sect. 4.

2 Methodology In this paper, the relationship between acceptance of driverless public transportation and passengers’ characteristics including gender, level of education, age, health condition, frequency of PT usage, motivation of trip made by PT, overall satisfaction from PT, and car ownership status has been examined using Fisher’s Exact Test (FET). FET is a statistical test used to determine if there are nonrandom associations between two categorical variables. The main reason we used FET (and not other frequently used tests of independences including Chi-square test of independence) to evaluate our hypotheses were: 1. FET is an exact test, therefore significance of the deviation from the “null hypothesis” can be calculated exactly, rather than relying on an approximation, however it requires more computational effort. 2. It can exactly evaluate the independencies between the studied variables in both small and unequally distributed datasets. 3. The assumptions of the simpler methods (e.g. chi-square test of independence) were violated in our dataset (e.g. expected values in the contingency tables for each cell should be more than 5 with no expected value less than 1 in chi-square test of independence). To do so, the following hypotheses have been formulated: H0(i): There is no significant relationship between passengers’ personal characteristic (i) and driverless PT user acceptance. H1(i): There is a significant relationship between passengers’ personal characteristic (i) and driverless PT user acceptance.

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where i = 1, …, 8 representing “gender”, “level of education”, “age”, “passenger’s health condition”, “frequency of PT usage”, “PT trip motivation”, “overall satisfaction from PT” and “car ownership status” of the passengers. In Fisher’s Exact Test, taking the m  n matrix of the observed states of the user acceptance-passenger characteristics into account, the conditional probability of getting the actual matrix given the particular column and row sums will be calculated as follows [14]. Pcutoff ¼

ðR1 !R2 !


Rm !ÞðC1 !C2 !


Cn !Þ Q ; N! i;j ai;j !

ð1Þ

where Ri (i = 1, …, m) = row sums in matrix of the observed values; Cj (j = 1, …, n) = column sums in matrix of the observed values; N = total sum of the matrix; ai, j = number of observations in which passenger characteristic is i and acceptance option is j. Furthermore the conditional probability (Pcutoff) of all the possible m  n matrices consistent with the row and column sums Ri and Cj will be calculated using the Eq. 1. Then the P-value of the test can be further calculated by sum of all p-values which are  Pcutoff. In the current paper, the above mentioned hypotheses were tested using Fisher’s Exact Test (FET) with the help of R programming language software. 2.1

Description of Data

In the current study, a questionnaire has been distributed in both the printed and electronic version in Budapest in which 374 (53.7% Male, 46.3% Female) respondents filled the questionnaire correctly. Overall, the sample consists of frequent public transport users (88.5% of daily users) with the car owner ship status of 15.8%. The majority of the participants fell between 18–28 (78.6%) and 28–38 (10.2%) age ranges. The respondents were all the normal public transportation users and not necessarily the already experienced driverless PT users. It should be highlighted that the respondents were asked to give their opinion regarding numerous aspects of public transportation including the availability of driverless public transportation in Budapest. Table 1 shows the collected personal characteristics of the respondents. Table 1. Collected passengers’ personal characteristics. Characteristic Gender Male Female Age range 14–18 18–28

N

%

201 53.7 173 46.3 6 1.6 294 78.6

Characteristic Level of education Primary Secondary University student/grad. Health condition Normal

N

%

8 2.1 109 29.1 257 68.7 321 85.8 (continued)

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Table 1. (continued) Characteristic N % Characteristic 28–38 38 10.2 Wheel chair 38–48 18 4.8 Visually impaired 48–58 8 2.1 Deaf 58–65 3 0.8 Dumb 65–75 4 1.1 Pregnant Above 75 3 0.8 Elderly Freq. of PT usage Mentally disabled < once per month 9 2.4 Car ownership At least once per month 6 1.6 Has car At least once per week 25 6.7 Doesn’t have car Daily 331 88.5 PT overall satisfaction Never 3 0.8 Very unsatisfied PT trip motivation Unsatisfied Study 256 68.4 Neutral Work 79 21.1 Satisfied Leisure 27 7.2 Very satisfied Other 12 3.2

N 4 8 5 9 3 11 13

% 1.1 2.1 1.3 2.4 0.8 2.9 3.5

59 15.8 315 84.2 4 1.1 10 2.7 78 20.9 186 49.7 96 25.7

3 Results and Discussion Initially the overall driverless public transportation (PT) user acceptance has been graphically investigated in Fig. 2.

Fig. 2. Overall evaluation of driverless PT user acceptance.

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By taking a wide look at Fig. 2, it is clearly obvious that the majority of the respondents had a positive orientation (50.5% selected “It is nice to try it” and 28.3% selected “Should be available” options) about driverless public transportation in Budapest, however, they are not fully sure (compare the number of respondents in “It is nice to try it” and “Should be available” options). This fact might show the necessity of improving the public information about driverless PT in Budapest. Moreover, a considerable portion of the respondents expressed that they are afraid of using driverless PT. It might be related to their health condition, level of education, their previous experiences etc. Furthermore, in the current study, the relationship between acceptance of driverless public transportation against gender, level of education, age, health condition, frequency of PT usage, motivation of trip made by PT, overall satisfaction from PT, and car ownership status has been examined using Fisher’s Exact Test. Table 2 shows the results of the Fisher’s Exact Test between each of the passengers’ characteristics and their idea (acceptance) about driverless public transportation. By taking a wide look at Table 2, one would find out that health condition of the passengers, frequency of PT usage, age, level of education and the motivation of the trip made by public transportation had the significant relationship with the acceptance of driverless PT transportation in Budapest. Table 2. Results of the Fisher’s Exact Test for driverless PT user acceptance – passengers’ personal characteristics relationship. Characteristics P-value Gender 0.08149 Level of education 0.01957* Age 0.00065*** Health condition 0.00003*** Frequency of PT usage 0.00054*** PT trip motivation 0.03141* PT overall satisfaction 0.1673 Car ownership status 0.6085 Significance: ***P  0.001, * P  0.05

The strong relationship between health conditions of the passengers with their acceptance opinion would emphasize the concept of equity whose relevance has been confirmed by studies in driving domain [15] as well as user acceptance studies of driverless vehicles [16]. This is a real fact that the passengers with special needs are a part of the entire passengers that should be carefully considered in the future driverless transport system including public transportation. Taking the Fig. 3 into account, the results of the current research shows the fact that passenger’s gender does not have a significant relationship with the acceptance of driverless public transportation unlike the user acceptance studies on automated driving systems that clearly showed men have a higher interest in automated driving than women, more positive orientation to automated driving [17–19].

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Fig. 3. Driverless PT user acceptance according to the gender of respondents.

Fig. 4. Driverless PT user acceptance according to the level of education of the respondents.

Hence, there is a significant difference between the user acceptance of driverless individual vehicles and driverless public transportation. Furthermore, it is interesting to mention that in the original UTAUT and UTAUT2 models proposed by Venkatesh et al. [11, 12] the gender of the users has been considered to be a moderator in the

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model while the results of the current study shows that, in the case of technology acceptance in public transportation unlike the private cars, the passengers gender does not have a significant relationship with their technology acceptance in public transportation. Moreover taking the level of education into account, Fig. 4 shows the fact that the respondents that were in the primary school level were not enough sure about their attitudes toward the driverless public transportation (the “should be available” and “should not be available” options are nearly zero). However, a considerable portion of the respondents in the secondary and university level of education are not aware of the potential consequences of these technologies in public transportation (pay attention to the “no idea” section in Fig. 4).

4 Conclusions The modern transportation system is walking step by step toward automation. As automated technology continuous to develop, the new technology offers a considerable opportunity to enhance public transportation systems especially in development and promotion of the sustainable mobility concepts. In general, driverless public transportation (taking all means of public transportation into account) can only become a reality if they are fully accepted by their target/potential users. In the current study, we were seeking for the other potential important users’ characteristics (passengers’ characteristics in public transportation domain) that might influence on their technology acceptance in public transportation domain to be considered as either the new moderators of the model or even a new model variable for the possible potential Budapest driverless public transportation user acceptance model (could be considered as the extension of UTAUT model for passengers’ technology acceptance in public transportation domain). To do so, the relationship between passengers’ personal characteristics and the acceptance of driverless public transportation has been examined by the means of Fisher’s Exact Test using the questionnaire survey done in Budapest. The results showed that the acceptance of driverless public transportation has a significant relationship with passengers’ age, health condition, frequency of public transport usage, level of education and motivation of the trip made by public transportation. It should be highlighted that the results of the current study showed that, unlike the private cars, the passengers’ gender does not have a significant relationship with their technology acceptance in public transportation. Acknowledgments. The authors would like to thank Mr. Blawal Hussain for his effort in data collection. The research reported in this paper was supported by the Higher Education Excellence Program of the Ministry of Human Capacities in the frame of Artificial Intelligence research area of Budapest University of Technology and Economics (BME FIKP-MI/FM). Moreover, the authors are grateful for the support of HAS (Hungarian Academy of Science) for providing the Janos BOLAYI Scholarship.

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References 1. Larsen, R.: Feasibility of advanced vehicle control systems for transit buses. Transp. Res. Rec. 1604(1), 155–162 (1997) 2. Lutin, J.M., Kornhauser, A.L.: Application of autonomous driving technology to transitfunctional capabilities for safety and capacity. Transp. Res. Rec. Paper (2014) 3. Winston, C., Mannering, F.: Implementing technology to improve public highway performance: a leapfrog technology from the private sector is going to be necessary. Econ. Transp. 3(2), 158–165 (2014) 4. Saif, M., Maghrour Zefreh, M., Torok, A.: Public transport accessibility: a literature review. Periodica Polytech. Transp. Eng. 47(1), 36–43 (2019). https://doi.org/10.3311/PPtr.12072 5. Hussain, B., Maghrour Zefreh, M., Torok, A.: Designing the appropriate data collection method for public transport passenger satisfaction analysis. Int. J. Traffic Transp. Eng. 8(2), 177–183 (2018). https://doi.org/10.7708/ijtte.2018.8(2).03 6. Pakusch, C., Bossauer, P.: User acceptance of fully autonomous public transport. In: Proceedings of the 14th International Joint Conference on E-Business and Telecommunications, vol. 4, pp. 52–60 (2017) 7. Fraszczyk, A., Mulley, C.: Public perception of and attitude to driverless train: a case study of Sydney, Australia. Urban Rail Transit 3, 100–111 (2017) 8. Madigan, R., Louw, T., Dziennus, M., Graindorge, T., Ortega, E., Graindorge, M., Merat, N.: Acceptance of automated road transport systems (ARTS): an adaptation of the UTAUT model. Transp. Res. Procedia 14, 2217–2226 (2016) 9. Riek, L., Howard, D.: A code of ethics for the human-robot interaction profession. In: Proceedings of We Robot (2014) 10. Davis, F.D.: Perceived usefulness, perceived ease of use, and user acceptance of information technology. MIS Q. 13(3), 319–340 (1989) 11. Venkatesh, V., Morris, M.G., Davis, G.B., Davis, F.D.: User acceptance of information technology: toward a unified view. MIS Q. 27(3), 425–478 (2003) 12. Venkatesh, V., Thong, J.Y., Xu, X.: Consumer acceptance and use of information technology: extending the unified theory of acceptance and use of technology. MIS Q. 36(1), 157–178 (2012) 13. Madigan, R., Louw, T., Wilbrink, M., Schieben, A., Merat, N.: What influences the decision to use automated public transport? Using UTAUT to understand public acceptance of automated road transport systems. Transp. Res. Part F Traffic Psychol. Behav. 50, 55–64 (2017) 14. Weisstein, E.W.: “Fisher’s Exact Test.” From MathWorld–A Wolfram Web Resource. http:// mathworld.wolfram.com/FishersExactTest.html. Accessed 19 Feb 2019 15. Adell, E., Várhelyi, A., Nilsson, L.: Modelling acceptance of driver assistance systems: application of the unified theory of acceptance and use of technology. In: Horberry, T., Regan, M.A., Stevens, A. (eds.) Driver Acceptance of New Technology: Theory, Measurement and Optimization, pp. 23–34. CRC Press, Boca Raton (2014) 16. Nordhoff, S., van Arem, B., Happee, R.: Conceptual model to explain, predict, and improve user acceptance of driverless podlike vehicles. Transp. Res. Rec. 2602(1), 60–67 (2016) 17. Kyriakidis, M., Happee, R., de Winter, J.C.: Public opinion on automated driving: results of an international questionnaire among 5000 respondents. Transp. Res. Part F Traffic Psychol. Behav. 32, 127–140 (2015) 18. Howard, D., Dai, D.: Public perceptions of self-driving cars: the case of Berkeley, California. In: Transportation Research Board 93rd Annual Meeting, vol. 14, no. 4502, pp. 1–16, January 2014 19. Schoettle, B., Sivak, M.: A survey of public opinion about autonomous and self-driving vehicles in the US, the UK, and Australia (2014)

Assessment of Crash Risks at Highway Access Points with Restricted Sight Visibility Sujata Basu(&)

and Pritam Saha

Indian Institute of Engineering Science and Technology, Shibpur, Howrah, India [email protected], [email protected] Abstract. The paper describes an approach of crash risk assessment at midblock access points of highways where sight visibility is restricted due to inadequate corner clearance and also prevailing traffic is mixed in character. Field study was conducted at two junctions on two-lane highways and site details as well as associated traffic data were captured; proportion of twowheeler and non-motorized vehicles was found to be significant at both the sites. A study of effects of mixed traffic on vehicle movements reveals that faster vehicles especially the bike riders often exhibit a tendency to swiftly overtake slower ones when they are impeded and accordingly sight distance needs for such vehicles increase to a considerable extent. Further, existence of vending shops at the corner of access points obstructs sight lines and reduces the sight distance available to drivers. On the basis of a descriptive statistical analysis, the paper demonstrated the effect of sight visibility on safety margins at access points. It was concluded that existence of vending shops significantly exaggerates crash risk at access points in the event of mixed traffic situations. Keywords: Access point Reliability


Crash risk
Sight visibility
Mixed traffic


1 Introduction Crash occurrences on highways largely depend on geometric elements and characteristics of traffic. It is observed that crash rate reduces significantly if the width of carriageway is increased [1] and a restriction on movement of heavy vehicles is imposed [2, 3]. Investigations indicate that additional road space acts as a buffer that helps in rectifying driving errors. Traffic segregation by way of providing exclusive truck lane eliminates interaction of truck and relatively faster vehicles, thereby, reduces the chances of such crashes. Further, at times drivers take risk while performing overtaking operations which eventually increases the chances of crashes to a considerable extent. Notably, such attempts are frequent on two-lane roads especially when the prevailing traffic is composed of vehicles with speed ranging from very slow to very fast. Faster vehicles are impeded and platoons are formed in consequence. Part of impatient drivers becomes reluctant to move in following and take overtaking attempts even if they do not have or cannot appropriately assess acceptable gap [4] for such operation. A study observed that assessment of acceptable gap is relatively easy during night time [5]; headlight helps in identifying the position of oncoming vehicle well in advance and minimizes the risk. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 76–88, 2020. https://doi.org/10.1007/978-3-030-38666-5_9

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Another major issue is direct accesses to adjoining areas; frequent access points interfere with the movement of main stream traffic which eventually increases the chances of vehicle conflicts. A number of studies have reported that highway crashes increase significantly when density of mid-block access is high [6–11]. Type and layout of such access points [12, 13] and inadequate sight distance and road signs [14] are observed to affect safety aspects significantly. Chances of risk exaggerate further if the prevailing traffic is mixed in character; a wide range of vehicles in terms of their static and dynamic characteristics under such traffic results in large speed differentials which have an impact in traffic operational characteristics. The current paper investigated the fact on the basis of a pilot study conducted on two-lane highways in India which exhibit mixed traffic and provide frequent access to abutting properties. Two sections were selected respectively on National Highway (NH) – 12 and 112 in a way such that in one section restrictions on sight visibility is high (NH-12) in majority of the access points whereas it is moderate in the other one (NH-112). Crash occurrences in the last five years both, in terms of total accident and casualty incidents were plotted (see Fig. 1) to inspect the impact of access points on road safety under mixed traffic. As anticipated, crash rate expressed as number of accidents/km/year (see Fig. 1a) and also, severity of those incidents examined using casualty incident data (see Fig. 1b) were found to be reasonably high on NH-12. For years, several studies have suggested measures like, full or even partial access control for improving highway safety [15–19]. However, it is not easy on two-lane roads due to practical reasons. Besides, under mixed traffic situation, many a time it is observed that slower vehicles especially the non-motorized ones make use of highway segments for local transportation due to easy access. At times faster vehicles are compelled to maneuver swiftly to avoid impedance caused by such slower ones, thereby, resulting in a considerable increase in sight distance needs for such vehicles. This fact along with restricted sight visibility at access points makes uncontrolled highway access extremely unsafe. Accordingly, it seems imperative to systematically assess the root causes of crash risk at such access points.

2 Objectives of the Study Crash rates on highways with mixed traffic are found to be considerably high in the event of frequent access points. Investigations indicate that such mishaps aggravate further especially when sight visibility at those access points is inadequate. Accordingly, it seems imperative to take initiatives aimed at understanding the impact of such uncontrolled access on highway crash occurrences. Therefore, the present study made an attempt to meet the following objectives: • Investigating the extent of variation in sight distance needs across vehicle types under mixed traffic situations. • Evaluating reliability of safety margins in terms of sight visibility at access points.

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Fig. 1. Accident statistics on highway sections with moderate (NH-12) and poor (NH-112) sight visibility at access points: (a) crash occurrences; (b) casualty incidents.

Fig. 2. Camera view at study sites (image by author): (a) access point type ‘A’ – sight visibility is moderately restricted; (b) access point type ‘B’ – sight visibility is highly restricted.

3 Data Description 3.1

Field Study

Both the highway sections (NH-12 and NH-112) considered in the current study were observed to exhibit similar roadway and traffic characteristics in terms of width of carriageway and shoulders, pavement condition, speed limit, composition and volume of traffic. However, rate of crash occurrences and also, severity of such crashes were found to be significantly high on one of the highway sections (NH-12) (see Fig. 1). On the basis of field investigation, it was made apparent that restrictions on sight visibility due to the existence of vending shops at majority of the access points on NH-12 is possibly the root cause of such higher rate. While, sight visibility at most of the access points on NH-112 was observed to be fairly good. Accordingly, two access points were selected respectively on NH-12 and NH-112 in a way that one of them is having moderate restriction on sight visibility whereas such restriction is high in the second one.

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They were designated as ‘access point type-A’ and ‘access point type-B’ respectively (see Fig. 2). Width of access roads was about 4.5 and 5.5 m respectively at type ‘A’ and ‘B’ access points. Table 1. Sample traffic data collected on the intersecting roads at access points. Vehicle type Time in (sec) Two-Wheeler 00:06:11:771 LCV 00:06:11:404 Three-Wheeler 00:06:24:584 Three-Wheeler 00:06:38:265 Bus 00:06:51:313 Three-Wheeler 00:06:04:893 Two-Wheeler 00:07:30:552 HCV 00:07:30:786 … … … … Note: LCV - Light Commercial

Time out (sec) 00:06:12:872 00:06:13:006 00:06:26:186 00:06:39:966 00:06:54:048 00:07:67:328 00:07:32:787 00:07:32:453 … … Vehicle; HCV -

Lapsed Time (sec) 1.101 1.602 1.602 1.701 1.735 1.435 1.235 0.667 … … Heavy Commercial

Speed (km/h) 32.70 22.50 22.50 21.16 20.75 25.09 29.15 53.97 … … Vehicle

Field study was conducted at the selected access points to capture the characteristics of traffic at both the intersecting roads. Video photographic survey technique was adopted in the current study for the purpose of collecting traffic data. A video camera was mounted on a stand height of which was adjusted in a way such that it can cover 100 m road stretch keeping some margin on either ends; ten traps each of 10 m wide were delineated on the road surface using reference lines. Traffic data was videotaped separately on both, access and main roads each for about 30 min. While extracting data, video files were played on a computer and time (t0, t1 …. t10) was noted when a vehicle just crosses the reference lines. Accordingly, trajectories of individual vehicle and their speeds were noted. Mean approach speed on both the highway sections was found to be in the range of 25–30 km/h, whereas, it was about 20 km/h on the access roads. Table 1 shows the sample traffic data collected on the intersecting roads at the study sites. Figure 3 displays observed vehicle composition at both the study sites. A look into the figure reveals that composition of traffic is more or less similar at both the highway sections. Proportion of two-wheeler and car was found to be significant: in the range of 33–37% and about 20%. On the road section next to the ‘access point type-B’, proportion of three-wheeler and non-motorized vehicles (NMV) was found to be somewhat higher compared to the other one; around 5%. On the access roads, proportion of NMV was observed to be significantly high; in a way that it shares about 30–50% of total traffic. This is attributable to the fact that on access roads number of motorized vehicles was considerably less except two wheelers. Further, narrow width of access road at access point type ‘A’ makes it difficult for drivers’ in maneuvering heavy vehicles like bus and truck. Notably, no such vehicles were observed on this road during field study except light commercial vehicles (LCV) which are used for transporting agricultural and commercial products (see Fig. 3b).

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Fig. 3. Observed traffic composition: at access point type ‘A’ – (a) main & (b) access road and at access point type ‘B’ – (c) main & (d) access road.

Fig. 4. A comparison of vehicular speeds based on fitted normal distribution function: (a) access point type ‘A’; (b) access point type ‘B’.

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3.2

81

Vehicle Speed Characteristics

At access points, it was felt imperative to examine the adequacy of sight visibility in meeting sight distances requirements at main and access roads. Accordingly, the current paper aimed at performing experiments with a wide range of percentile speeds in order to assess the safe speeds at such intersection. However, computation of percentile speeds necessitates describing speed data mathematically using a distribution function. Typically, speed data (v) follows a symmetrical distribution about a central value and is expressed statistically using normal distribution function (see Eq. 1).   1 1 v  l2 f ðvÞ ¼ pffiffiffiffiffiffi  exp  ; 2 r r 2p

ð1Þ

where l – mean and r – standard deviation of the distribution. Maximum likelihood estimation (MLE) [20], method of moments [21], minimum chi-square method [22], and simultaneous numerical estimation [23] are generally used for the purpose of obtaining a calibrated expression of distribution functions. However, the current study applied maximum likelihood method since it has been found effective even if the sample size is not large [24]. Parameters were estimated (see Table 2) by maximizing the log-likelihood function (Eqs. 2 and 3) for the speed data obtained at the study sites. ^Þ ¼ Lðu ^Þ ¼ ln Lðu

Yn i¼1

Xn i¼1

f ðhi j^ uÞ;

ð2Þ

ln f ðhi j^ uÞ;

ð3Þ

^ Þ parameter vector; f ðhi j^ where ðu uÞ – probability density function. Further, in traffic engineering problems, chi-square test and the Kolmogorov– Smirnov (K-S) test are commonly used for the purpose of testing goodness-of-fit of the selected distributions. The current study, however, used Kolmogorov–Smirnov (K-S) test since it offers certain advantages over chi-square test: it can use data with a continuous distribution and there is no minimum frequency per test interval [25]. Table 2 displays the K-S test statistic values computed by determining the difference between the cumulative percentage of the measured and expected frequency. Hypothesis tests were also performed and interpretations were made based on p-value and level of significance (a) of the test. The null hypotheses for each test were as follows: the compatibility hypothesis of speed distribution with fitted model was rejected (Pvalue < a) or not rejected (P-value > a). Table 2 shows that null hypothesis is ‘not rejected’ when the speed data, collected at the intersecting roads at both the access points, are fitted to normal distribution function. Figure 4 contemplates the calibrated expressions of normal distribution respectively for type ‘A’ and ‘B’ access points. At access point type ‘A’, it was found that presence of speed bumps reduces speed to a considerable extent at the access road. While at access point type ‘B’, due to nonexistence of such bumps speed differential at the intersecting roads was found to be insignificant.

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Table 2. Goodness-of-fit test details and the estimated parameters of the fitted distribution. Access type

Intersecting road

Mean, km/h

Standard deviation, km/h

K-S test statistic

pvalue

a

Null hypotheses

A

Main Access Main Access

31.50 16.70 22.95 20.40

12.75 8.44 10.81 8.585

0.103 0.073 0.083 0.132

0.116 0.059 0.216 0.786

0.05 0.05 0.05 0.05

Do Do Do Do

B

not not not not

reject reject reject reject

4 Results and Discussions 4.1

Intersection Sight Distance Requirements

Prevailing traffic at the study sites was observed to be mixed in character and composed of a wide range of vehicle types including non-motorizes ones. A large variation in approach speeds, ranging from very slow to even about 30 km/h, was observed for such vehicles. Besides, it is anticipated that drivers’ of such vehicles considerably vary in their responses especially in the event of complex and unexpected information. Thus, sight distance requirements significantly differ across vehicle types which eventually pose an additional challenge in providing safe road environment at access points under such traffic. Stopping sight distance was calculated using Eq. 4: distance that a vehicle travels during perception-reaction time of the driver plus braking distance needed to stop the vehicle. SSD ¼ 0:278Vt þ

V2 ; 254f

ð4Þ

where SSD – stopping sight distance, m; V – speed of the vehicle, km/h; t – perceptionreaction time of the driver, s; f – coefficient of longitudinal friction between vehicle tires and road pavement. Perception-reaction time depends on both, human factors like driver’s age, gender, and experience and also, situational factors like expectation, urgency and cognitive load [26]. A study has shown that in general the mean value of drivers’ perceptionreaction time to an unexpected object scenario lies between about 1.1–1.28 s while 95th percentile value was found to be 2 s for the same condition [27]. Indian roads congress guidelines, however, suggests a high value of 2.5 s as perception reaction time of drivers in order to take the variability of driver characteristics into account in design [28]. Current study, however, performed experiments with 0–3 s to understand the impact of drivers’ perception on sight distance needs. Further, coefficient of longitudinal friction depends on speeds of vehicles and the manual suggests values ranging between 0.35–0.40; the value reduces with the increase of speed. Assessment of stopping sight distance under such traffic was made considering the fact that speeds vary across vehicle types and operating conditions as well. It was observed that the 98–40th percentile range, V98–V40, reasonably approximates the speed of almost all types of motorized vehicles prevalent at the intersection; distributions of approach speed were used to determine vehicle speed percentiles (see Fig. 4). Figure 5

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Fig. 5. Chart showing sight distance requirements at: access point type ‘A’ – (a) main & (b) access road and access point type ‘B’ – (c) main & (d) access road.

displays requirements of sight distance at the intersecting roads of access point type ‘A’ and ‘B’ respectively. A look into the plot reveals that sight distance needs at the study sites are more or less similar. This signifies that the primary grounds of road mishaps at such access points are attributed to restriction in sight visibility. 4.2

Assessment of Safety Margins

As hypothesized in Sect. 4.1, under mixed traffic situation sight distance requirements vary considerably across vehicle types. Empirical investigations indicate that speeds of motorized vehicles could be reasonably approximated in terms of percentile speeds ranging between V98–V40. The current study, however, considered a range of V85–V50 at the time of analyzing safety aspects keeping in view the fact that insignificant proportion vehicles was observed outside of such speed range at the time of field study. Subsequently, sight triangles were formed on the basis of sight distance scenarios prevalent at main roads and zones clear of obstructions in the vicinity of the access points. Such triangles were placed over the layouts of the access points and available sight distances were accordingly determined (see Fig. 6) to evaluate safety margins: defined as the difference between available and required sight distance. Subsequently, an attempt was made to assess safety and reliability of traffic at both the access points. A spectrum of studies suggested the use of probability of noncompliance, ‘Pnc’ in order to point out the probability of a design that does not meet the

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standard [29–32]. Mathematically, a design situation can be described in terms of a performance function or limit state function g(x) wherein x is an n-dimensional design variable vector; this is represented as a balance between supply and demand [33]. Equation 5 demonstrates the function considering a simple two-variable system; in the context of the current study, available sight distance (ASD) can be considered as supply and stopping sight distance (SSD) can be considered as demand. Equation 7 demonstrates the way of obtaining ‘Pnc’, wherein f(x) is the joint probability distribution function for input design variables [34]. gð xÞ ¼ ASD  SSD ;

ð5Þ

ðxÞ  0 () Failure or noncompliance; ZZ Z Pnc ¼ Pðg  0Þ ¼ . . . . . . f ð xÞdx:

ð6Þ

gðxÞ  0

ð7Þ

Equations 8 and 9 represent mean (ls ) and standard deviation (rs ) of safety margin considering the fact that ASD and SSD are uncorrelated. The reliability index (b) of a system which is assumed to be normally distributed is explained by the standard normal variate of performance function, g(x) [33] and can be expressed by Eq. 10 based on the assumptions that both, ASD and SSD are also normally distributed. A study suggested simplified approach of determining probability of noncompliance, ‘Pnc’ and expressed it in terms of Eq. 11; where U is the standard normal cumulative distribution function [34]. Eventually, the system reliability that refers to the complements to the probability of noncompliance can be derived from Eq. 12. ls ¼ E ðASDÞ  E ðSSDÞ;

ð8Þ

pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi rs ¼ Var ðASDÞ þ Var ðSSDÞ;

ð9Þ

b¼

ls EðASDÞ  EðSSDÞ ¼ pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ; rs Var ðASDÞ þ Var ðSSDÞ

ð10Þ

Pnc ¼ UðbÞ;

ð11Þ

Reliability ðRÞ ¼ 1  Pnc :

ð12Þ

Table 3 summarises the probability of noncompliance scenario of available and stopping sight distance at the access roads (both, at type ‘A’ and ‘B’ access points). It was found that at type ‘A’ access point reliability of ‘stopping sight distance less than available sight distance’ is about 30% which however reduces to around 10% in case of type ‘B’ access point. This is primarily attributable to restricted sight visibility to the drivers of approaching vehicles at such access points.

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Fig. 6. Restrictions on sight visibility due to obstructions: access point (a) type ‘A’ (b) type ‘B’. Table 3. Probability of noncompliance scenario of available and stopping sight distances. Access point ASD (m) SSD (m) b [Ref: Eq. 10] Pnc = u(−b) R = 1 − Pnc Mean SD Mean SD Type A 9.384 0.661 15.626 2.397 −0.505 0.693 0.307 Type B 2.792 0.427 18.282 2.520 −1.186 0.882 0.118 Note: ASD: available sight distance at access roads, SSD: stopping sight distance at access roads, SD: stand. deviation, b: reliability index, Pnc: probability of noncompliance, R: reliability of available sight distance

Fig. 7. Vehicle trajectories on highway segments next to access point (a) type ‘A’ (b) type ‘B’.

A further attempt was made to explore vehicle-following movement under mixed traffic using trajectory data. Figure 7 illustrates vehicle trajectories captured on the main roads at intersection approach in which gradient of any trajectory denotes a particular vehicle speed. A look into the plots reveals that such trajectory largely depends on dynamics of the following vehicle. For instance, a few cars and two-wheelers were observed to take overtaking attempts even at intersection approach resulting in larger

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stopping sight distance needs. High speed vehicle manoeuvre at access point, consequently, poses additional challenges in providing safe road environment.

5 Conclusions Easy access on highways often encourage the drivers of slower vehicles especially the non-motorized ones to make use of highway segments for the purpose of local transportation. The resultant traffic on the highway segment then exhibits a character of truly mixed traffic; composed of vehicles with speed ranging from very slow to very fast. Many a time, drivers’ of faster vehicles, especially bike riders, are observed to have a tendency to maneuver swiftly to avoid impedance caused by slower ones. As a result of it, sight distance needs for such vehicles increase to a considerable extent and quite often it is found to exceed the sight distance available to drivers. Chances of risk aggravate further when roadside vending shops are observed to exist at access points. Presence of these shops beyond acceptable limits results in inadequate corner clearance at such location. Sight lines are then obstructed which subsequently make available sight distance insufficient in meeting the safe stopping sight distance needs. Accordingly, it was felt imperative to conduct a study aimed at assessment of crash risks at midblock access points of highways where sight visibility is restricted due to inadequate corner clearance. While performing field investigations, two junctions were selected on two-lane highways; in a way such that at both the locations the prevailing road traffic is mixed in character and also, sight visibility is restricted significantly at one junction whereas such restrictions are somewhat less in the other one. Inspection of field data shows that at both the study sites, proportion of two-wheeler and non-motorized vehicles (NMV) is significant and majority of bike riders attempt to swiftly overtake NMVs without even shifting to the adjacent lane. This entails a need of evaluating sight distance needs across vehicle types under such traffic and subsequently examining the instances when such needs exceed the available sight distance. Eventually, the paper presented a descriptive statistical analysis of the effect of sight visibility on safety margins at these access points. It was found that sight distance needs are more or less similar at both the study sites; however, historical data indicates one of the study sites to have high crash occurrences. Field reconnaissance and subsequent empirical investigations eventually substantiate the fact that sight visibility significantly exaggerates crash risk at access points especially in the event of mixed traffic situations. Acknowledgement. The authors would like to thank The Institution of Engineers (India) for providing financial assistance under IEI R&D Grant-in-Aid scheme. Project No.: R.6/2/DR/201819/RDDR2018001 [Permanent ID: DR2019001].

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References 1. Harwood, D.W., Bauer, K.M., Richard, K.R., Gilmore, D.K., Graham, J.L., Potts, I.B., Torbic, D.J., Hauer, E.: NCHRP Web-Only Document 129, Phases I and II: Methodology to Predict the Safety Performance of Urban and Suburban Arterials. Transportation Research Board of the National Academies, Washington, D.C. (2007) 2. Kobelo, D., Patrangenaru, V., Mussa, R.: Safety analysis of Florida urban limited access highway with special focus on the influence of truck lane restriction policy. J. Transp. Eng. 134(7), 297–306 (2008) 3. Reddy, G.V., Thakkar, J., Vargas, F.: The effect of lane use restriction for trucks on traffic operations and safety. In: Enhancing Transportation Safety in the 21st Century, ITE International Conference (1999) 4. Khoury, J.E., Hobeika, A.G.: Assessing the risk in the design of passing sight distances. J. Transp. Eng. 133(6), 370–377 (2007) 5. Llorca, C., Moreno, A.T., García, A., Pérez-Zuriaga, A.M.: Daytime and nighttime passing maneuvers on a two-lane rural road in Spain. Transp. Res. Rec. J. Transp. Res. Board 2358, 3–11 (2013) 6. Elvik, R.: A synthesis of studies of access point density as a risk factor for road accidents. Accid. Anal. Prev. 107, 1–10 (2017) 7. Cafiso, S., DiGraziano, A., DiSilvestro, G., LaCava, G., Persaud, B.: Development of comprehensive accident models for two-lane rural highways using exposure geometry, consistency and context variables. Accid. Anal. Prev. 42(4), 1072–1079 (2010) 8. Brimley, B.K., Saito, M., Schultz, G.G.: Calibration of highway safety manual safety performance function: development of new models for rural two-lane two-way highways. Transp. Res. Rec. J. Transp. Res. Board 2279(1), 82–89 (2012) 9. Avelar, R.E., Dixon, K.K., Brown, L.S., Mecham, M.E., Van Schalkwyk, I.: Influence of land use and driveway placement on safety performance of arterial highways. Transp. Res. Rec. J. Transp. Res. Board 2398(1), 101–109 (2013) 10. Huang, B., Zhang, Y., Lu, L., Lu, J.J.: A new access density definition and its correlation with crash rates by microscopic traffic simulation method. Accid. Anal. Prev. 64, 111–122 (2014) 11. Alluri, P., Gan, A., Diaz, A., Steiner, R.: Safety impacts of access management features near roundabouts. Transp. Res. Rec. J. Transp. Res. Board 2517, 28–36 (2015) 12. Li, J., Abdelwahab, W., Brown, G.: Joint effects of access and geometry on two-lane rural highway safety in British Columbia. Can. J. Civ. Eng. 21(6), 1012–1024 (1994) 13. Tang, C.C., Zhang, T.J., Wu, L.T.: Safety impact on accesses in two-lane highways. J. Highw. Transp. Res. Dev. 2(2), 103–107 (2007) 14. Basu, S., Roy, N., Saha, P.: Assessment of safety performance on two-lane roads under mixed traffic: a review of recent research and future research needs. In: 97th Annual Meeting of the Transportation Research Board, no. 18-01404 (2018) 15. Gwynn, D.W.: Accident rates and control of access. Traffic Eng. Institute of Traffic Engineers, Washington, D.C. 37(2), 18–21 (1966) 16. Box, P.C., Associates: Traffic control and roadway elements - their relationship to highway safety. Chapter 4. Intersections; Chapter 5. Driveways. In: Highway Users Federation for Safety and Mobility (1970) 17. Stover, V.G., Adkins, W.G., Goodknight, J.C.: Guidelines for medical and marginal access control on major roadways. NCHRP Report 93, Transportation Research Board, Washington, D.C. (1970)

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18. Roy Jorgensen Associates, Inc.: Cost and safety effectiveness of highway design elements. NCHRP Report 197, Transportation Research Board, Washington (1978) 19. OECD: Road safety research: a synthesis. Organization for Economic Co-operation and Development, Paris, France (1986) 20. Myung, I.J.: Tutorial on maximum likelihood estimation. J. Math. Psychol. 47, 90–100 (2003) 21. Wang, X., Peng, Z.: Method of moments for estimating uncertainty distributions. J. Uncertain. Anal. Appl. 2(1), 5 (2014) 22. Kominek, Z.: Minimum chi-squared estimation of stable distributions parameters: an application to the Warsaw Stock Exchange. J. Appl. Stat. 29(5), 729–744 (2002) 23. Vasconcelos, L., Silva, A.B., Seco, Á., Silva, J.P.: Estimating the parameters of Cowan’s M3 headway distribution for roundabout capacity analyses. Baltic J. Road Bridge Eng. 7, 261–268 (2012) 24. Luttinen, R.T.: Properties of Cowan’s M3 headway distribution. Transp. Res. Rec. J. Transp. Res. Board 1678, 189–196 (1999) 25. Ye, F., Zhang, Y.: Vehicle type-specific headway analysis using freeway traffic data. Transp. Res. Rec. J. Transp. Res. Board 2124, 222–230 (2009) 26. Mehmood, A., Easa, S.M.: Modeling reaction time in car-following behaviour based on human factors. Int. J. Appl. Sci. Eng. Technol. 5(14), 93–101 (2009) 27. Fambro, D.B., Koppa, R.J., Picha, D.L., Fitzpatrick, K.: Driver perception–brake response in stopping sight distance situations. Transp. Res. Rec. J. Transp. Res. Board 1628, 1–7 (1998) 28. Recommended Practice for Sight Distance on Rural Highways (IRC-66). Indian Roads Congress (IRC), Ministry of Road Transport & Highways (MORTH, formerly MOST). New Delhi (1976) 29. Essa, M., Sayed, T., Hussein, M.: Multi-mode reliability-based design of horizontal curves. Accid. Anal. Prev. 93, 124–134 (2016) 30. Richl, L., Sayed, T.: Evaluating the safety risk of narrow medians using reliability analysis. J. Transp. Eng. 132(5), 366–375 (2006) 31. Hussein, M., Sayed, T., Ismail, K., Van Espen, A.: Calibrating road design guides using riskbased reliability analysis. J. Transp. Eng. 140(9), 04014041 (2014) 32. Navin, F.P.D.: Safety factors for road design: can they be estimated? Transp. Res. Rec. J. Transp. Res. Board 1280(1), 181–189 (1990) 33. You, K., Sun, L., Gu, W.: Reliability-based risk analysis of roadway horizontal curves. J. Transp. Eng. 138(8), 1071–1081 (2012) 34. de Santos-Berbel, C., Essa, M., Sayed, T., Castro, M.: Reliability-based analysis of sight distance modelling for traffic safety. J. Adv. Transp. (2017)

Basic Methods to Support City Bus Fleet Conversion Towards a 100% Electric Bus Fleet Krzysztof Krawiec(&) Faculty of Transport, Silesian University of Technology, Krasinskiego 8, 40-019 Katowice, Poland [email protected]

Abstract. The transition process taking place in public transport, from conventional bus fleet towards a 100% electric one, requires a scientific approach. Proper formulation and description of the fleet conversion process is a complex, multithreaded and multi-faced task, in solving which basic methods may be helpful. These include: an identification model based on statistical methods, an optimisation model based on multi-criteria optimization methodology, an interaction model based on the methods of discrete Markov chains and economic models, enabling realistic consideration of any proposed solution based on simulation methods. The article formulates requirements for basic methods, their input and output data and divide them into groups with regard to social, technological, economic, environmental and political analysis (known as STEEP analysis). These methods may contribute to a formal formulation of a fleet conversion optimisation problem. The paper also describes intermediate stages in fleet conversion process as well as three different approaches to city bus fleet conversion to achieve a fully electric city bus fleet in transit company. Keywords: Public transport


Battery electric bus
Electromobility

1 Introduction Processes to phase out the exploitation of Diesel buses that take place in transport (including public transport), lead to forward-looking discussions on future of urban bus fleet among scientists and practitioners. In these discussions the following – among others – are to be taken into account: limited range resulting from imperfect battery technology and the necessity of purchasing charging facilities [1]. Numerous research works and implementation projects have been carried out over the last few years [2–5]. A general objective of these projects is to achieve an increase in the number of electric buses in public transport. However, they do not solve the problem of reaching a 100% share of electric buses used in the fleet of a transit companies. This is a subject matter of the PLATON ‘Planning Process and Tool for Step-by-Step Conversion of the Conventional or Mixed Bus Fleet to a 100% Electric Bus Fleet’ project, being performed by a multi-national consortium [6]. Major basic stages in creating electric bus fleet are presented in [7], whereas essential functionalities of the project are presented in [8].

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 89–98, 2020. https://doi.org/10.1007/978-3-030-38666-5_10

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Proper formulation and description of the bus fleet conversion process is a complex, multi-threaded and multi-faceted task and is not sufficiently presented in the literature. In this paper a few basic methods are presented that may support the process of city bus fleet transition into an all-electric city bus fleet.

2 Basic Methods 2.1

An Overview

There are numerous determinants of the city bus fleet conversion process, which should be mapped in the form of variables describing the states of the system within the process. The analysis of these states enables the identification of factors and their influence on the process. The group of basic methods includes: • • • •

An identification model based on statistical methods. Optimisation model, based on multi-criteria optimization methodology. Interaction model, based on the methods of discrete Markov chains. Economic models, enabling realistic consideration of any proposed solution based on simulation methods. • Information technology (IT) methods necessary for the development of a computeraided application. The identification model is used for qualitative description of the tested system and its environment and for full specification of basic problems being the subject of analysis. It requires detailed specification of the following elements [9]: • The area served by the transit company, considering landscape planning and potential for its development and the resulting changes. • Transport systems in the analysed area with their characteristics. • Transport infrastructure pertinent to the process. • Public transport organisation and fleet policy in the transit company. • The time scope of the analysis, including time frames defined at the strategic and operational level. • Stakeholder groups, taking into account the relationships between them as well as their objectives and needs in terms of fleet conversion in strategic and operational terms (each potential stakeholder should also be assessed in terms of the capacity, constraints and decision-making conditions for taking a variety of actions related with the process). • Political and socio-economic conditions in which the fleet conversion process takes place. The identification model should be constructed in a way that takes into account the system approach, in which internal elements and elements of the environment are distinguished.

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The optimisation model is a quantitative tool which should be used to shape the strategy of fleet conversion. It provides scientific research methods and tools, enabling a multifaceted approach to the analysed issues. When building the optimization model one should consider mapping of transport infrastructure (with a particular attention to public transport infrastructure), bus fleet structure, issues related to batteries and charging stations. One should also investigate the environmental impact of fleet conversion process and assess its cost and resulting therefrom benefits. Interaction model is based on the methods of discrete Markov chains. It requires the mapping of a set of relations, which can be analysed in different cross-sections and categories, depending on the way of how disciplinary subsets are defined, but also current research needs. It should be emphasized that the relations are illustrated by very complex hierarchical relationships and functional dependencies that may occur between elements of the fleet conversion process. The model has to include – among others – the fleet transition matrix, an initial distribution across the state space and Kolmogorov–Chapman equations. Practical implementation of interaction model will require time mapping in the form of complex systems of discrete events. Economic models are based on standards methods of calculation of short, medium and long-term cost and benefits structure, adequately for each proposed solution. The results of the economic models will depend on the results of simulations of electricity consumption, the cost structure of the company and the strategy of fleet conversion. Examples of economic models are presented among others in [10–12]. The IT methods necessary for the implementation of a computer application should be divided into three subgroups: • Methods for data collection. • Methods for recording interactions. • Methods enabling the creation of a modern interface that encourages the use of the IT tool. For all the base methods it is necessary to define the input variables, the range of values they can take and their availability in the case to be analysed. 2.2

Inputs of Basic Methods

The set of inputs of the basic methods is divided into five thematic areas, referring to the STEEP analysis [13]: • • • • •

Inputs Inputs Inputs Inputs Inputs

of of of of of

basic basic basic basic basic

methods methods methods methods methods

related related related related related

to to to to to

social factors. technological factors. economic factors. environmental factors. political factors.

In the whole society, as well as in its local structures, there is a growing awareness that conventional way of travelling is burdened with excessive social costs. Thus, inputs of basic methods related to social factors shall include, among others, the level of social pressure associated with reducing air pollution, the degree of understanding of the inevitability of change in terms of fleet conversion, the level of belief of transport

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organisers and operators (as well as passengers) of desirability of inducting electricpowered fleet in public transport. In terms of basic methods related to technological factors, all the parameters associated with electric buses and charging facilities should be taken into account. Particularly important are the following: the range of the bus, battery capacity, the way of charging and its efficiency and availability of time intervals for charging. It must be noted that there is a strong impact of local conditions for technological issues in the fleet conversion process. For the implementation of economic models, it is necessary to estimate the cost structure and expected effects in short, medium and long-term. Assumed context of the objective function (achieving the 100% electric bus fleet in transit company) suggests that the cost structure should be defined in two dimensions: long-term and mediumterm costs in the field of fleet conversion and long-term and medium-term costs in the field of electric bus exploitation. Significant inputs are these related with ecological issues. Admittedly, electric buses do not emit harmful substances in the place of operation, but greenhouse gases arise at the stage of electricity production. For the prepared life cycle of electric buses, the carbon footprint method can be used to calculate the environmental impact of greenhouse gas emissions. We must not forget that the fleet conversion process is affected by political factors. Legislative amendments, instability of transport policy at European and national levels may cause significant fluctuations in the process. 2.3

Outputs of Basic Methods

Output data of basic methods are the following: results, calculations and suggestions in terms of bus fleet conversion. Among these the most important are: • Results of simulation of fleet conversion process as a suggestion for public transport organiser (e.g. local authorities) and operator (e.g. transit company). • Economic calculation of fleet conversion process. • Suggestions in terms of charging strategy and technology. • Hierarchy (ranking) of vehicle cycles, liable to be operated by electric buses. In Fig. 1 the concept of graphical representation of the set of outputs of the basic methods in their relation to the set of inputs related to social, technological, economic, environmental and political factors, as well as to the basic methods themselves, are presented. Choosing the proper basic method depend on local conditions, financial situation of the stakeholders and espoused fleet conversion strategy. An outline of a way to achieve a 100% electric bus fleet is presented in further part of the paper.

Basic Methods to Support City Bus Fleet Conversion Input data of basic methods

Set of basic methods

Output data of basic methods

Input data related with social factors

Idenficaon model based on stascal methods

The results of the simulaon of the exchange proces as a sugeson for public transport organisors and operators

Input data related with technical and organizaonal factors

Opmisaon model based on mul-criteria opmisaon methodology

Input data related with econimic factors

Interacon model based on the methods relang to discrete markov chains

Input data related with ecological factors

Economic models based on simulaon methods, enabling realisc consideraon of any proposed soluon

Input data related with polical and juridical facors

IT methods necessary for the implementaon of computer applicaon

93

Economic calculaon of the conversion process

Suggesons for conversion-related infrastructure

Hierarchy (ranking) of transport tasks

Fig. 1. Input and output data of basic methods of fleet conversion process.

3 Towards an All Electric Bus Fleet in Transit Company Due to limited financial resources and vibrant technology development it is to be expected that the fleet conversion process will take place in stages. Striving for a 100% stake of electric buses it is necessary to apply intermediate stages which assume only partial fleet exchange. In Fig. 2 multifarious ways to achieve fully electric bus fleet are presented. Different markings of lines have been introduced to improve readability of various approaches to the fleet conversion process.

Share of electric buses [%]

100

0 Time

Fig. 2. Intermediate stages in fleet conversion process (own study based on [14]).

Decisions on subsequent purchases of electric buses are taken at different time points, depending in particular on financial resources, but also on technical and organizational circumstances. It should be noted that time points in which intermediate stages in fleet conversion process take place are theoretical. These time points may also result from a simulation which is to be carried out with the use of other methods.

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On the grounds of research and consultations with fleet conversion stakeholders, three approaches to city bus fleet conversion process are defined: • Partial replacement of conventional buses with electric ones without changing the bus schedule. • Partial replacement of conventional buses with electric ones without changing bus schedule on the basis of a hierarchy of vehicle cycles. • Aiming to replace 100% of the fleet allowing bus schedule corrections. In the first case we are to check out which vehicle cycles are capable to be operated by electric buses. A vehicle cycle is understood as a sequence of bus stops on the route carried out by a bus on bus lines around the clock from the moment of leaving the depot to the return to the depot. In this case unwillingness to fit (change) the bus schedule to the specificity of electric buses in assumed. This means that such vehicle cycles are sought after, during the realisation of which no discharging of battery will occur. The concept of partial replacement of conventional buses with electric ones without changing the bus schedule is presented in Fig. 3.

Vehicle cycle no. 1 (Diesel bus)

Test for discharging in case of operation of the vehicle cycle no. 1 by an electric bus

Vehicle cycle no. 1 (electric bus)

It is possible to operate this vehicle cycle by an electric bus

Vehicle cycle no. 2 (Diesel bus)

Test for discharging in case of operation of the vehicle cycle no. 2 by an electric bus

Vehicle cycle no. 2 (diesel bus)

It is NOT possible to operate this vehicle cycle by an electric bus

Vehicle cycle no. 3 (Diesel bus)

Test for discharging in case of operation of the vehicle cycle no. 3 by an electric bus

Vehicle cycle no. 3 (electric bus)

It is possible to operate this vehicle cycle by an electric bus

Vehicle cycle no. 4 (Diesel bus)

Test for discharging in case of operation of the vehicle cycle no. 4 by an electric bus

Vehicle cycle no. 4 (electric bus)

It is possible to operate this vehicle cycle by an electric bus

n-th vehicle cycle (Diesel bus)

Test for discharging in case of operation of n-th vehicle cycle by an electric bus

n-th vehicle cycle

It is (or it is NOT) possible to operate this vehicle cycle by an electric bus

Fig. 3. Partial replacement of conventional buses with electric buses without changing the bus schedule.

In a given transport network there are n vehicle cycles, operated by conventional buses at the start of the simulation. Subsequent vehicle cycles are analysed for discharging characteristics in case of operation by electric buses. Supposing – on the basis of simulations – battery discharge, it is not possible for this very vehicle cycle to be operated by an electric bus at this stage of technological development. If, as a result of a simulation a bus will be able to return to the depot after fulfilling the entire vehicle cycle without being discharged, that means that it is possible to operate this vehicle cycle with the use of electric buses. Consequently, we have a set of vehicle cycles divided into these which are and which are not possible to be operated by electric buses.

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The fact that there are vehicle cycles which are not possible to be operated by electric buses does not mean that achieving a target of a 100% share of electric buses is infeasible. This only means, that these vehicle cycles are not suitable to be operated by electric buses at this stage of battery and charging technology development. It is to be expected that over time, with the increase of battery capacity, an increase in advancement in charging technologies and energy efficiency of buses, the number of vehicle cycles being ready for operation by electric buses will be increasing. The next case differs from the former one in the formation of the hierarchy (ranking) of vehicle cycles which are capable to be operated by electric buses (carried out on the basis of formerly performed energy-demand analysis). With the increase in the share of electric buses, a new decision problem arise: which vehicle cycles should be operated by electric buses, considering the economic limitations and technological (most of all: battery capacity, charging infrastructure, limited range of a bus). In case of limited funds and the consequent lack of purchase opportunities of the required number of electric buses (equal to the number of vehicle cycles) the following selection becomes necessary: which vehicle cycles (of those which are possible) select to be operated by electric buses first? Figure 4 sets out the issue of a partial replacement of conventional buses with electric buses without changing the bus schedule.

Vehicle cycle no. 1 (electric bus)

SEARCHING FOR THE MOST SUITABLE VEHICLE CYCLES TO BE OPERATED BY ELECTRIC BUSES

HIERARCHY (RANKING) OF VEHICLE CYCLES READY TO BE OPERATED BY ELECTRIC BUSES Vehicle cycle no. 3 (electric bus) T HE EASIEST TASK T O BE OPERATED BY AN ELECTRIC BUS

Vehicle cycle no. 2 (diesel bus)

Vehicle cycle no. 4 (electric bus) T HE SECOND EASIEST TASK T O BE OPERATED BY AN ELECTRIC BUS

Vehicle cycle no. 3 (electric bus)

Vehicle cycle no. 4 (electric bus)

Vehicle cycle no. 1 (electric bus) T HE MOST DIFFICULT, BUT POSSIBLE VEHICLE CYCLE T O BE OPERATED BY AN ELECTRIC BUS

SET OF OTHER VEHICLE CYCLES UNREADY TO BE OPERATED BY ELECTRIC BUSES (at this stage of battery technology development) Vehicle cycle no. 2 (diesel bus) BUSINESS AS USUAL OPERATION

n-th vehicle cycle (diesel bus)

n-th vehicle cycle (diesel bus) BUSINESS AS USUAL OPERATION

Fig. 4. Partial replacement of conventional buses with electric buses without changing the bus schedule on the basis of a hierarchy of vehicle cycles.

Similarly as in the case described above, in Fig. 4 we have n vehicle cycles. Here, however, these vehicle cycles are not only tested for discharging – the most suitable vehicle cycles shall be sought having regard to selected decision variables using multicriteria decision support methods. This results in the hierarchy (ranking) of vehicle

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cycles ordered from the easiest vehicle cycle to the most difficult one – but still possible to be operated by an electric bus. If, as a result of the application of the above mentioned methods, no serviceability by electric buses will be achieved the following possibilities are to be considered: • Partial change of bus schedule by increasing time slots on bus stops equipped with charging infrastructure to charge battery to sufficient level. • Decision on a brand new bus schedule developed for compliance with limitations of electric buses. • Implementation of the new charging infrastructure in order to condense the charging facilities throughout the network. • Postulates regarding required bus parameters which should be met in the future. A graphical illustration of this issue is presented in Fig. 5.

SET OF POSSIBLE SOLUTIONS FOR FURTHER INVESTIG ATION

Partial change of bus schedule SET OF OTHER VEHICLE CYCLES UNREADY TO BE OPERATED BY ELECTRIC BUSES (at this stage of battery technology development)

Vehicle cycle no. 2 (diesel bus)

Searching for a new bus schedule

Decision on a brand new bus schedule

BUSINESS AS USUAL OPERATION

n-th t vehicle cycle (diesel bus)

Implementation of the charging infrastructure

BUSINESS AS USUAL OPERATION

Postulates regarding required bus parameters

Fig. 5. Aiming to replace 100% of the fleet allowing bus schedule corrections.

It is noteworthy that any change of bus timetable made solely because of the technical limitations of electric buses is highly unwelcomed by transit companies and organisers of public transport. In certain countries, there is also a sort of subordination of transit company to local authorities, which means the transfer of responsibility for the fleet conversion process at political level.

4 Summary The inevitability of public transport electrification seems to be foredoomed. To support this process, basic methods presented in the article might be used. The correct choice of basic methods, iterative definition of input and output variables can allow a methodological approach to the achievement of a 100% electric bus fleet in transit company operating a public transport system.

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Due to financial and organizational limitations, an one-off exchange of conventional buses with electric ones seems unlikely to happen in the majority of cities. This view is based on financial constraints, the structure of bus fleets and the observation of the fleet conversion process in many European cities. Hence, it should be considered at which points in time how many electric buses to exchange. In the article intermediate stages are defined – partial replacement of conventional buses with electric buses without changing the bus schedule with the aim to replace 100% of the fleet allowing bus schedule corrections. In the first case the vehicle cycles are divided into these which are capable to be operated by electric buses and others, not ready to be operated by electric buses yet. The division is made on the grounds of discharging characteristics analysis, carried out with the use simulation methods. In the second case vehicle cycles capable to be operated by electric buses are organised based on a hierarchy (ranking) of vehicle cycles. The purpose of this is to help interested parties in deciding on allocation of newly purchased or planned to be purchased electric buses to the vehicle cycles in a given transport network. The hierarchy of vehicle cycle will facilitate decision making in terms of the choice of vehicle cycles to be operated by electric buses first. It is worth noting that only these vehicle cycles are included in the hierarchy, which are not at risk of discharging of battery. In the last case, aiming to replace 100% of the fleet allowing bus schedule corrections, the vehicle cycles unable to be operated by electric buses (at this stage of technology development) are analysed. As a solution to this problem the following are proposed: partial or complex change of the timetable, implementation of the new charging infrastructure and postulates regarding required bus parameters to fulfil these vehicle cycles with the use of electric buses. Acknowledgments. The present research has been financed from the means of the National Centre for Research and Development as a part of the international project within the scope of ERANET EMEurope programme ‘Planning Process and Tool for Step-by-Step Conversion of the Conventional or Mixed Bus Fleet to a 100% Electric Bus Fleet’.

The project "Planning Process and Tool for Step-by-Step Conversion of the ConvenƟonal or Mixed Bus Fleet to a 100% Electric Bus Fleet” has been financed from the means of the NaƟonal Centre for Research and Development (Poland) within the scope of ERANET EMEurope programme.

References 1. Varga, B.O., Iclodean, C., Mariasiu, F.: Electric and Hybrid Buses for Urban Transport Energy Efficiency Strategies. Springer, Cham (2016) 2. Naumann, S., Büchter, H., Janecki, R., Karoń, G., Sierpiński, G.: CACTUS models and methods for the evaluation and the optimal application of battery charging and switching technologies for electric busses. Deliverable 3.1 Methods (2015). http://www.cactusemobility.eu/CACTUS_Deliverable_3.1_Methods.pdf. Accessed 21 Feb 2019

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3. ZeEUS eBus Report. An overview of electric buses in Europe. http://zeeus.eu/uploads/ publications/documents/zeeus-ebus-report-internet.pdf. Accessed 21 Feb 2019 4. ZeEUS eBus Report No. 2. An updated overview of electric buses in Europe. http://zeeus.eu/ uploads/publications/documents/zeeus-ebus-report-2.pdf. Accessed 21 Feb 2019 5. ASSURED project Homepage. https://assured-project.eu/. Accessed 21 Feb 2019 6. PLATON project Homepage. http://platon.publictransport.info/. Accessed 21 Feb 2019 7. Algin, V.: Electrification of urban transport. Basic stages in creating electric buses fleet. Mech. Mach. Mech. Mater. 3(44), 5–17 (2018) 8. Algin, V.B., Czogalla, O., Kovalyov, M.Y., Krawiec, K., Chistov, S.: Essential functionalities of ERA-NET electric mobility Europe PLATON project. Mech. Mach. Mech. Mater. 4(45), 24–35 (2018) 9. Karoń, G., Krawiec, K., Krawiec, S., Kłos, M.J., Markusik, S., Sobota, A., Żochowska, R.: Naukowe instrumenty wsparcia inwersji floty autobusów miejskich z floty konwencjonalnej na zasilaną elektrycznie. Pr. Nauk. Tolitechniki Warszawskiej Transp. 121, 125–134 (2018) 10. Krawiec, S., Karoń, G., Janecki, R., Sierpiński, G., Krawiec, K., Markusik, M.: Economic conditions to introduce the battery drive to busses in the urban public transport. Transp. Res. Procedia 14, 2630–2639 (2016) 11. Jwa, K., Lim, O.: Comparative life cycle assessment of lithium-ion battery electric bus and diesel bus from well to wheel. Energy Procedia 145, 223–227 (2018) 12. Li, X., Castellanos, S., Maassen, A.: Emerging trends and innovations for electric bus adoption—a comparative case study of contracting and financing of 22 cities in the Americas, Asia-Pacific, and Europe. Res. Transp. Econ. 69, 470–481 (2018) 13. Fleisher, C., Bensoussan, B.: Strategic and Competitive Analysis: Methods and Techniques for Analyzing Business Competition. Prentice Hall, Upper Saddle River (2002) 14. Krawiec, S., Łazarz, B., Markusik, S., Karoń, G., Sierpiński, G., Krawiec, K., Janecki, R.: Urban public transport with the use of electric buses – development tendencies. Transp. Probl. 11(4), 127–137 (2016)

Analysis of Pedestrian Movements on Sidewalks: A Case Study in Kolkata, India Deotima Mukherjee1

, Soumyadip Das2(&) and Sudip K. Roy3

, Pritam Saha3

,

1

2

Civil Engineering Department, Indian Institute of Technology Delhi, Delhi 110016, India [email protected] Civil Engineering Department, National Institute of Technology Durgapur, Durgapur 713209, India [email protected] 3 Civil Engineering Department, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India [email protected], [email protected]

Abstract. This paper focuses on investigating the effect of sidewalk frictions on pedestrian movements. The study accordingly analysed the characteristics of pedestrians on five sidewalk zones selected on the basis of their land-uses. Traffic data was videotaped and bi-directional movement was captured. Empirical investigations demonstrate that hourly flow at the public transport terminal is significantly high throughout the day, while in recreational area usually it starts increasing since afternoon. Presence of buffer has an effect on speed of female pedestrians; however, such effect was insignificant in case of males. Speed of pedestrians reduces considerably if they carry baggage. Notably, it was more in commercial areas compared to public transport terminals. This is attributable to the fact that majority of daily commuters carry lighter baggage which has little or no effect on their speeds. Capacity drops down with the decrease in effective width which however does not have considerable impact on free-flow speeds. Also, the study found that sidewalk frictions affect speeds of pedestrians’ irrespective of their age and gender and capacity as well. Keywords: Pedestrians
Sidewalk facility parameters
Mixed traffic


Land use
Traffic flow

1 Introduction Walking is a vital mode of transportation. Every person, irrespective of their social stature, is a pedestrian at some point of the day, as all journeys start and end as a walking trip. Thus, the importance of pedestrian movements is accepted globally and cannot be overlooked. Walking directly influences the use of other modes and a good walking facility is essential in connecting the users with the mass transit facilities. In this age of high fuel cost, encouraging walking also helps in improving the economy to some extent. Further, growing number of road traffic results in an increase of air and noise pollution. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 99–111, 2020. https://doi.org/10.1007/978-3-030-38666-5_11

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Development of recreational and shopping areas near residential localities is a common affair these days. Proper sidewalk facility may encourage pedestrians to opt for walking rather than using automobiles to reach their destinations. This, accordingly, warrants construction of distinctive pedestrian facilities in terms of sidewalks or footpaths, or at least marking a space on the road for the safe movement of pedestrians, in case an exclusive facility cannot be provided. Often movement of pedestrians is also affected due to frictions like, on-street parking and encroachment of street vendors. Shoulders of urban roads are sometimes observed to function as sidewalks; however, in several occasions, it is noticed that they are occupied either by vehicles for the purpose of parking or by street vendors. Further, poor maintenance of the sidewalks compels pedestrians to spill onto the carriageway and move along with the vehicular traffic. As a result, chances of conflicts between the pedestrians and vehicles increase to a great extent. This calls for an initiative to investigate characteristics of pedestrian movement under prevailing traffic conditions while taking infrastructure related decisions. The current paper, accordingly, made an attempt to analyse pedestrian movements on sidewalks in different land uses where variation in traffic characteristics is significant.

2 Literature Review The movement of pedestrians in metropolitan cities is essential for sustaining a good socio-economic as well as a healthy life. Smooth and safe movements of pedestrians, however, call for facilities that provide adequate space to them. Appropriate planning and designing of such facilities warrant an extensive knowledge on their walking behaviour. For years a number of researchers reported the characteristics of pedestrian flow in the urban context. A number of studies on pedestrians’ speed reveal that male pedestrians walk faster than female pedestrians, and also walking speed reduces with their age [1–5]. Fitzpatrick et al. [6] observed that the 15th percentile walking speed of younger pedestrians (1.15 m/s) is larger than those of older pedestrians (0.92 m/s). In another study, Arango and Montufar [7] compared the walking speed of older pedestrians using canes with those who walk without such assisting devices. They observed that older males walk faster than older females without the supportive devices. However, they did not observe any impact of gender difference on walking speed when the supports are used. Tarawneh [3] and Carey [8] studied the effect of group movements on walking speed extensively and opined that group size comprising of more than two pedestrians causes an incremental increase in relative interaction between them; this results a significant reduction in walking speed. Kadali et al. [9] conducted a study in India on pedestrian gap acceptance behaviour. They suggested use of multi-linear regression (MLR) as well as Artificial Neural Network (ANN) as effective tools in assessing contributing factors influencing gap acceptance process. Several international studies have reported that walking speeds are greatly influenced if pedestrians perform any sort of activity while walking. Morrall et al. [10] observed that people carrying baggage walk slower than those without any baggage. In a study conducted in airport terminals, Young [11] found no significant variation in the walking speed of pedestrians who carry baggage. However, Rastogi et al. [12] observed

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significant impact of carrying of baggage on walking speed. They also observed such speeds to vary with age, gender and type of sidewalk facilities. An experience of pedestrian movements in New York indicates that pedestrians wearing headphones and those who talk on cell phones walk slowly [13]. Loeb and Clarke [14], however, reported adverse effects of cell phone usage on pedestrian’s speed and safety as well. Effect of land uses on pedestrian speeds is considerable. Al-Masaeid et al. [15] found that land use pattern of the surroundings is an important factor influencing the walking speed of pedestrians in developing countries. They also observed a significant difference in the walking speeds of pedestrians due to the variations of land uses, such as business, residential and shopping areas. Lam and Cheung [16] observed that pedestrian speed in commercial areas are faster than those in recreational areas, and the walking speed of the pedestrian is dependent on the surrounding environment. Daamen and Hoogendorn [17] elucidated the fact that speed of pedestrians is influenced by various characteristics like width, type of facility, and environmental factors. McDonald [18] suggested that social environment is an important factor influencing the walking behaviour of child pedestrians, and also for short-distance walking trips. Wells and Yang [19] found that land-use pattern also affects the walking behaviour, and reported that pedestrians in non-residential areas have less tendencies to walk. Bornstein and Bornstein [20] pointed to the fact that pedestrians living in cities with a large population walk faster than those living in cities with small population. They opined that a relationship exists between the walking speed and population of the city. The speed of pedestrians varies with geographic locations. For instance, mean walking speed of pedestrians on sidewalks was found to be about 79 m/min in Haifa, Israel [2], 74 m/min in Singapore [21], 65 m/min in Riyadh [22]. A number of studies, on the other hand, reported that walking behaviour is even governed by facility types. Lam and Cheung [16] compared pedestrian speeds on different facilities and concluded that pedestrians on indoor walkways walk slowly than those on outdoor walkways; this attributes to the effect of the environment. Kumar and Parida [23] observed that pedestrian crossing activities have a higher rate of fatality than other activities like standing or walking on roadside. Parida et al. [24] also observed that a grade separated facility (skywalk) provides a safe and comfortable journey to the pedestrians. Basile et al. [25] proposed a methodology for assessing safety level of pedestrian crossings, across 17 European cities, irrespective of the presence and absence of traffic light. Kretz [26] and Polus et al. [2] defined Level of Service concept respectively through a microscopic simulation based on the original density-based scheme and three regime linear speed density regression models. Majority of the above cited studies are carried out in more or less homogeneous traffic situations. There have been a handful number of studies that have so far reported the characteristics of pedestrian movements under mixed traffic situations. Thus, the current study made an attempt to examine pedestrian flow characteristics under mixed traffic conditions at sidewalks.

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3 Study Sites and Field Data Five locations were selected in the city of Kolkata covering a wide range of land-use pattern for the collection of field data. These were precisely residential, educational, commercial and recreational areas. The study locations are categorized as ‘sidewalk’ provided along the side of the carriageway to facilitate walking. The sidewalks are separated from the carriageway by means of un-mountable curbs and guard rails along its sides; this makes pedestrian movements free from any vehicular conflicts. Zones that encompass commercial hubs and public transport terminals are observed to have sidewalk width of about 4.5 m in order to accommodate high volume of pedestrians. In residential zones, about 3 m sidewalk width is observed. However, presence of a restaurant along the road side creates bottleneck and obstructs the flow in consequence. As a result, pedestrians needed to maintain a buffer distance in several occasions. Encroachments of book stalls in educational area create a buffer and significantly reduce the effective width of the facility. The study site in such area is observed to have a width of 2.6 m. The width in recreational area was appreciable as there was no confinement in terms of physical barrier. However, street furniture, like benches, and trees seem to reduce the effective width to 3.5 m. Video-photographic survey technique was adopted while collecting field data (Fig. 1). A video camera was mounted at an elevation, away from the view of pedestrians, which captured bi-directional flow of pedestrians on each of the chosen sites. The recording was done covering morning and evening peak hours, as well as off-peak hours from 8 a.m. to 9 p.m., on a typical weekday. The recorded video files were then played in a computer and pedestrian volume count was conducted to contemplate the hourly traffic variations. The time taken by a random pedestrian to cross the trap length of 10 m was, also, noted keeping an accuracy of 0.01 s. The pedestrian speeds were accordingly determined on the basis of such lapsed time.

Fig. 1. A view of video photographic survey: showing the camera (inset) fitted to an elevated mast.

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Fig. 2. Observed hourly flow variation of pedestrians at the study sites.

The recorded pedestrian volume was plotted against time to interpret the hourly traffic variation pattern. Figure 2 depicts such variation across the selected locations. The volume at the public transport terminal was significantly higher, as compared to all the other locations, throughout the day. The flow rate in educational and commercial area was observed to be moderate and also, the trend line passes through insignificant changes. Conversely, morning and evening peaks of such flow was apparent in residential area. This is owing to the fact that most of the residents go to their work place in the morning and return during the evening. However, flow variation pattern is somewhat different in the recreational site where flow reaches its peak during the afternoon and after around 6 p.m., suddenly it drops and becomes almost zero. The opening and closing time of the nearby tourist spot seems to be the cause of such variation. Characteristics of pedestrians, such as age and gender, as well as associative activities such as carrying any baggage, were also noted from the videos. The age of the pedestrians was assumed based on approximate eye estimation. The age groups were classified as children: age up to 15 years, adult: age 16–45 years and elderly: above 45 years. The flow parameters were then evaluated for the selected study sites.

4 Pedestrian Speed Statistics Walking speeds were observed in regard to age and gender of pedestrians and also if they carry any baggage. Pedestrians who move with light baggage were, however, considered in the category of without baggage. As anticipated, the mean speed of the elderly pedestrians was the lowest at all the study sites (Fig. 3a). Further, their walking speed was observed to be significantly lower for the commercial and educational zones where it was in the range of 60–64 m/min. This is due to the fact that in these areas, presence of buffers, like book stalls, street vendors etc. reduced the effective width, which eventually compelled them to compromise their desired speed. Whereas, in

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residential and recreational areas they mostly walk to keep them physically and mentally fit and accordingly their speed increases even up to 69 m/min. The presence of buffer, also, hindered the movement of female pedestrians in the educational area as they try to maintain a “shy distance” with the buffer (Fig. 3b).

a)

b)

c) Fig. 3. Pedestrian characteristics and walking speeds at different land uses: (a) effect of age; (b) variation with gender; (c) impact of carrying luggage.

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However, variations in mean speed of male pedestrians were observed to be insignificant, ranging between 70–75 m/min, in almost all the locations; this is owing to the fact that even in highly congested situations, male pedestrians prefer to maneuver, rather than lowering their speeds (Fig. 3b). Effect of carrying baggage on pedestrians’ speed is illustrated in Fig. 3c. It is evident that carrying baggage has an impact on their speed which is maximum in commercial areas where weight of such luggage is expected to be quite high. However, in public transport terminals pedestrians are mostly daily commuters and generally they carry comparatively lighter baggage. Further, such effect was found to be the least in the recreational area since pedestrians were observed to carry light baggage which does not affect their speed. Observations indicate a mean speed of about 70–75 m/min for those who do not carry baggage while it was in the range of 68–73 m/min in the event of carrying any baggage. Variation in mean speed was insignificant for female pedestrians, even if they carried any baggage.

5 Parameter Extraction and Empirical Investigations 5.1

Speed-Density Relationship by Land Use

The general relationship adopted for the analysis is derived from the single-regime model and given by: S ¼ a  bD;

ð1Þ

where S – pedestrian speed; D – density. Scatter plot of the data points exhibits a linear relationship between speed and density of pedestrians: average speed of pedestrians’ decreases with the increase in density and it continues until density reaches the jam condition, wherein pedestrian movement completely stops (Fig. 4a). Table 1 displays the relationships, obtained with reasonable statistical validity in terms of R2. The free flow speeds of pedestrians at different land uses were observed in the range of 72–82 m/min; similar results were also obtained in a fairly recent study conducted in India [27]. In commercial areas, it is typical that pedestrians move quite swiftly in most of the occasions, thereby, resulting in high free speed. Frequent book stalls in educational zones act as a buffer and cause hindrance to the pedestrian movements; this consequences significant reduction in free speed values. Moreover, the presence of wider sidewalk results in comparatively higher jam density values in public transport terminal and recreational areas. 5.2

Speed-Flow Rate Relationship by Land Use

The parabolic relationship of speed-flow rate is expressed by the following equation: Q ¼ Sa  where Q – pedestrian flow rate.

S2 ; b

ð2Þ

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The established relationships reveal that the average speed of pedestrians decreases gradually with the increase of flow, till it reaches to the capacity. Thereafter, frequent interaction under jammed conditions results in simultaneous decrease of both speed and flow (Fig. 4b). The parabolic relationships that best fit the data points exhibit acceptable statistical validity in terms of R2 (Table 1). As expected, the capacity at the recreational area turned out to be the maximum, among all the sites, with a value of 86.9 ped/m/min and that for the educational site was the lowest with a value of 49.02 ped/m/min. This is owing to the fact that the recreational area has comparatively wider sidewalks, whereas for the educational area, the effective width of the sidewalk is significantly reduced by the buffer. The observed results are to some extent comparable with the capacity values provided in the Indian Roads Congress guidelines [28]: wherein capacity for a sidewalk of width 2.6 m is about 3,654 ped/m/hr or 60.9 ped/m/min. 5.3

Flow Rate-Density Relationships by Land Use

The flow rate-density relationship also follows a parabolic trend as expressed in Eq. (3). Q ¼ aD  bD2

ð3Þ

The established relationship implies that the density of pedestrians increases with an increase in the flow rate. This is attributed to the fact that along with a rise in the flow rate, the number of pedestrians using the sidewalk facility increases thus raising the density as a subsequence (Fig. 4c). This trend continues till capacity is reached, wherein pedestrian streams reach the critical density. Beyond this point, density keeps increasing as more pedestrians enter the stream; however, in such condition, the flow starts decreasing due to frequent interaction and consequent congestion. Table 1 provides the density-flow rate relationships obtained for different land uses. 5.4

Flow-Area Module Relationship by Land Use

Area module is the reciprocal of density. Accordingly, the flow-area module relationship (see Eq. 4) is obtained by replacing density in Eq. (3). Q¼

a b  2; M M

ð4Þ

where M – area module or space of pedestrian. At the zero flow condition, the space requirement for an individual pedestrian is equal to the projected area of the body ellipse, which indicates that the area module cannot be equal to zero (Fig. 4d). Table 1 provides the flow rate-area module relationships for different land uses. Figure 4d indicates that in the public transport terminal and recreational sites, space required per person is more as compared to other land uses. Majority of the pedestrians carry baggage with them and also move hurriedly in the former while in recreational zones they usually expect to have ample space so as to walk comfortably. Also, the presence of guard rails along the sidewalks in public

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transport terminal area further restricts the available space and hinders the movements; this necessitates pedestrians to walk faster in that inadequate space, rather than compromising their desired speed. The minimum area module is observed in the range of 0.21–0.35 m2/ped, while at maximum flow level it is in the range of 0.46–0.93 m2/ped (see Table 2). Table 1. Relationships of flow parameters at sidewalks for different land use characteristics. Land use

Relation

Commercial

Speed-Density Speed-Flow rate Flow rate-Density Flow rate-Area Module Recreational Speed-Density Speed-Flow rate Flow rate-Density Flow rate-Area Module Residential Speed-Density Speed-Flow rate Flow rate-Density Flow rate-Area Module Educational Speed-Density Speed-Flow rate Flow rate-Density Flow rate-Area Module Public transport terminal Speed-Density Speed-Flow rate Flow rate-Density Flow rate-Area Module

Model equation

R2 value Sample size

S = 85.82 − 23.75D Q = S(85.82 − S)/23.75 Q = D(85.82 − 23.75D) Q = 85.82/M − 23.75/M2 S = 77.76 − 17.38D Q = S(77.76 − S)/17.38 Q = D(77.76 − 17.38D) Q = 77.76/M − 17.38/M2 S = 81.81 − 21.35D Q = S(81.81 − S)/21.35 Q = D(81.81 − 21.35D) Q = 81.81/M − 21.35/M2 S = 72.91 − 26.11D Q = S(72.91 − S)/27.11 Q = D(72.91 − 27.11D) Q = 72.91/M − 27.11/M2 S = 80.71 − 19.16D Q = S(80.71 − S)/19.16 Q = D(80.71 − 19.16D) Q = 80.71/M − 19.16/M2

0.366 0.572 0.994 0.994 0.478 0.503 0.997 0.997 0.302 0.628 0.899 0.899 0.445 0.566 0.991 0.991 0.723 0.800 0.995 0.995

1,240

647

585

1,043

1,648

Table 2. Descriptive statistics of pedestrian flow at sidewalks for different land uses. Location

Free-flow speed (m/min)

Jam density (ped/m2)

Max. flow rate (ped/m/min)

Area module (m2/ped) At qmax. Min.

Commercial Educational Recreational Public transport terminal Residential

85.82 72.91 77.76 80.71

3.61 2.79 4.47 4.21

77.52 49.02 86.90 84.99

0.55 0.74 0.46 0.48

0.28 0.35 0.21 0.24

81.81

3.83

63.21

0.93

0.28

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a)

b)

c)

d) Fig. 4. Characteristics of pedestrian flow parameters at selected land uses: (a) speed-density; (b) speed-flow rate; (c) flow rate-density; (d) flow rate-area module relationships.

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Table 3. Gender and age distributions observed at study sites. Location

Gender frequency (%) Male Female Commercial 89.91 10.09 Educational 82.16 17.83 Recreational 75.11 24.88 Public transport terminal 88.17 11.83 Residential 81.02 18.97

Age frequency (%) Children 0.16 0.28 0.31 0.78 1.02

Adult 89.91 82.16 75.11 88.17 81.02

Elderly 10.09 17.83 24.88 11.83 18.97

Table 3 illustrates the distribution of gender and age at the study sites. Proportion of male pedestrian was considerably higher than the females in all the locations. The presence of elderly was significant at the recreational site, as they prefer such locations for morning walks or leisure trips. Similarly, maximum number of children and adults emerged at the residential zone, because of school and work based trips.

6 Conclusions Walking behaviour varies significantly with the change in land-use pattern. Thus, the location-specific characteristics of pedestrian traffic flow warrant comprehensive study at the facilities of different zones in a city. This paper identified five zones on the basis of their land uses and analysed the characteristics of pedestrian traffic at sidewalk facilities of these zones; they were designated as facilities at commercial, educational, recreational, public transport terminal and residential respectively. Empirical investigations revealed that trends of speeds change with regard to both, locations and genders, and also, patterns of temporal flow variations of different zones vary considerably with the land use. Further, meticulous examination focused on macroscopic parameters indicates considerable variation in capacity and jam density as well. Notably, hourly flow rate at the public transport terminal was tremendously high throughout the day. In residential zone, peak flow typically occurs during morning and evening periods, because of home based and work based trips. While for the rest of the day, flow was, however, observed to be very less with not much of variation. Commercial and educational zones exhibit a consistent rate of flow during working hours. In case of recreational areas, the nearby tourist spot regulates the demand flow which, was quite less in the morning period and gradually starts increasing since the afternoon. The impact of various factors on the pedestrian speed, like age and gender of pedestrians and also when they carry any baggage, was quantified for different land uses. The decrease in the effective width of a facility, owing to buffers, like book stalls, street vendors etc., has in general, caused reduction in walking speeds. While, it is the opposite for pedestrians walking in residential areas; this is because of low volume of pedestrians when compared to other sites and also, sizable proportion of exercisewalkers. Another noteworthy fact is that presence of buffer mostly hinders the movement of female pedestrians as usually they try to maintain a ‘shy distance’. Expectantly, speed reduction of pedestrians with baggage is large in commercial areas,

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which, however is insignificant in public transport terminals wherein mostly they are daily commuters and carry comparatively lighter baggage. Further, the mean speeds of the elderly pedestrians are found to be lowest at all the study sites and variation in these speeds is insignificant. The present study finds that proportion of males is higher than females irrespective of land uses. Share of elderly was more in recreational site and that of children and adults was more in residential zone. Observations indicate that the elderly prefer such locations for morning walks or leisure trips whereas school and work based trips account for larger proportion of children and adults as revealed. Empirical investigations indicate satisfactory relationships between macroscopic flow parameters: pedestrian speed, flow, density and area module. Pedestrians’ speed is purpose specific. This could be exemplified by their behaviour in commercial area where they have the tendency to move swiftly in most of the occasions resulting in higher free flow speeds. Moreover, wider space in sidewalks, as observed in public transport terminal and recreational zones, increases the jam density as more number of pedestrians could be trapped inside. Accordingly, capacity of sidewalks in those locations increases significantly and also the area module was observed to be the least. Acknowledgement. The paper is based on a part of the data collected in the CSIR-CRRI, New Delhi sponsored project “Development of Indian Highway Capacity Manual (INDO-HCM)”. The authors sincerely acknowledge CSIR-CRRI.

References 1. Fruin, J.J.: Pedestrian Planning and Design. Metropolitan Association of Urban Designers and Environmental Planners, New York (1971) 2. Polus, A., Schofer, J.L., Ushpiz, A.: Pedestrian flow and level of service. J. Transp. Eng. 109 (1), 46–56 (1983) 3. Tarawneh, M.S.: Evaluation of pedestrian speed in Jordan with investigation of some contributing factors. J. Saf. Res. 32(2), 229–236 (2001) 4. Montufar, M., Arango, J., Porter, M., Nakagawa, S.: Pedestrians’ normal walking speed and speed when crossing a street. Transp. Res. Rec. J. Transp. Res. Board 2002(1), 90–97 (2007) 5. Finnis, K.K., Walton, D.: Field observations to determine the influence of population size, location and individual factors on pedestrian walking speeds. Ergonomics 51(6), 827–842 (2008) 6. Fitzpatrick, K., Brewer, M.A., Turner, S.: Another look at pedestrian walking speed. Transp. Res. Rec. 1982, 21–29 (2006) 7. Arango, J., Montufar, M.: Walking speed of older pedestrians who use canes or walkers for mobility. Transp. Res. Rec. 2073(1), 79–85 (2008) 8. Carey, N.: Establishing pedestrian walking speeds. Portland State University, Portland (2005) 9. Kadali, B.R., Vedagiri, P., Rathi, N.: Models for pedestrian gap acceptance behavior analysis at unprotected mid-block crosswalks under mixed traffic conditions. Transp. Res. Part F: Traffic Psychol. Behav. 32, 114–126 (2015) 10. Morrall, J.F., Ratnayake, L.L., Seneviratne, P.N.: Comparison of central business district pedestrian characteristics in Canada and Sri Lanka. Transp. Res. Rec. 1294, 57–61 (1991)

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11. Young, S.B.: Evaluation of pedestrian walking speeds in airport terminals. Transp. Res. Rec. 1674, 20–26 (1999) 12. Rastogi, R., Thaniasaru, I., Chandra, S.: Design implications of walking speed for pedestrian facilities. J. Transp. Eng. 137(10), 687–696 (2011) 13. Pedestrian Level of Service: Phase I, Department of City Planning, Transportation Division, New York (2006) 14. Loeb, P.D., Clarke, W.A.: The cell phone effect on pedestrian fatalities. Transp. Res. Part E: Logist. Transp. Rev. 45, 284–290 (2009) 15. Al-Masaeid, H.R., Al-Suleiman, T.I., Nelson, D.C.: Pedestrian speed flow relationship for central business areas in developing countries. Transp. Res. Rec. 1396, 69–74 (1993) 16. Lam, W.H.K., Cheung, C.: Pedestrian speed/flow relationships for walking facilities in Hong Kong. J. Transp. Eng. 126(4), 343–349 (2000) 17. Daamen, W., Hoogendoorn, S.P.: Free speed distributions—based on empirical data in different traffic conditions. In: Waldau, N., Gattermann, P., Knoflacher, H., Schreckenberg, M. (eds.) Pedestrian and Evacuation Dynamics 2005, pp. 13–25. Springer, Heidelberg (2007) 18. McDonald, N.C.: Travel and the social environment: evidence from Alameda County, California. Transp. Res. Part D: Transp. Environ. 12(1), 53–63 (2007) 19. Wells, N.M., Yang, Y.: Neighborhood design and walking: a quasi-experimental longitudinal study. Am. J. Prev. Med. 34(4), 313–319 (2008) 20. Bornstein, M.H., Bornstein, H.G.: The pace of life. Nature 259, 557–559 (1976) 21. Tanaboriboon, Y., Hwa, S.S., Chor, C.H.: Pedestrian characteristics study in Singapore. J. Transp. Eng. 112(3), 229–235 (1986) 22. Koushki, P.A.: Walking characteristics in Central Riyadh, Saudi Arabia. J. Transp. Eng. 114 (6), 735–744 (1988) 23. Kumar, P., Parida, M.: Vulnerable road users in multi-modal transport system for Delhi Journeys, LTA (2011) 24. Parida, P., Shah, J., Gangopadhyay, S.: Feasibility of providing a skywalk for pedestrian in Chandni Chowk, Delhi. Indian Highw. 42, 20–29 (2014) 25. Basile, O., Persia, L., Usami, D.S.: A methodology to assess pedestrian crossing safety. Eur. Transp. Res. Rev. 2(3), 129–137 (2011) 26. Kretz, T.: A level of service scheme for microscopic simulation of pedestrians that integrates queuing, uni- and multi-directional flow situations. Eur. Transp. Res. Rev. 3(4), 211–220 (2011) 27. Kotkar, K.L., Rastogi, R., Chandra, S.: Pedestrian flow characteristics in mixed traffic conditions. J. Urban Plan. Dev. 136(1), 23–33 (2010) 28. IRC: 103. Guidelines for pedestrian facilities (First revision). The Indian Roads Congress, New Delhi (2012)

Simulation Processes of Construction of Optimal Routes for the Delivery of Goods by Road Transport on Urban Road Network in Mountainous Cities Viktor Danchuk1 , Talal Ameen2, Olena Bakulich1 and Vitaliy Svatko1(&) 1

,

National Transport University, Kyiv 01010, Ukraine [email protected] 2 Himiko Tech, 170150 Quito, Ecuador

Abstract. A method of optimization of cargo delivery routes in the conditions of non-stationary dynamics of traffic flows on the urban road network sections for cities located in mountainous areas is proposed. In doing so, the emergence of such non-stationary states is due to the influence of natural factors on the structural characteristics of the urban road network (seismically-active influences, floods, mudflows, landslides, etc.). The method is based on the use of a modified ant algorithm. In the frameworks of the proposed method, a test simulation is carried out for the mountainous city of Quito, the capital of Ecuador. The obtained results of the research point to the prospect of application of the proposed method for finding the optimal routes for the delivery of goods, taking into account the specifics of the road network of cities, within which transportation is carried out. Keywords: Optimal route
Ant algorithm
Traffic flow
Mountainous terrain

1 Introduction Accelerated motorization in the conditions of backlog development of urban road networks (URN) leads to a sharp increase in the number of vehicles on highways, the intensification of traffic. This, in turn, significantly affects the workload of URN, contributes to the occurrence of the congestion and a decrease in the speed of traffic. Long congestion on the roads is increasingly causing not only temporary, but also economic losses. The main thing in urban transport logistics is the solution of routing problems using such methods of route optimization that would effectively take into account the actual dynamics of traffic flows on URN. The reasons for the constant change in the dynamics of traffic flows may be road traffic accidents, large numbers of vehicles, road conditions, natural phenomena affecting the state of the URN. Particularly interesting is the consideration of the dynamics of transport flows of the URN in cities located in the mountains under conditions of seismically-active influences such as earthquakes, floods, landslides, etc. These natural phenomena can lead to sudden, unpredictable © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 112–121, 2020. https://doi.org/10.1007/978-3-030-38666-5_12

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destruction of URN sites and, accordingly, affect the infrastructure of transport systems. This, in turn, causes the emergence of non-stationary states of the dynamics of traffic flows at certain sections of the URN and the need for an operational solution to the problems of routing in such conditions. Thus, the relevance of the study is determined by the need to develop, implement and apply appropriate models, methods and software to optimize and manage the transport process in conditions of non-stationary dynamics of traffic flows on the URN. The use of such developments will increase the efficiency of transportation of goods within cities, especially in those cities that are located in mountainous areas. The paper considers the application of the method based on the use of the modified ant algorithm for the construction of optimal routes for the delivery of goods on the URN. This URN is characterized by the presence of sections of increased steepness, curvature, limited visibility and high accident rate. Simulation has been conducted for the URN of the mountainous city of Quito, the capital of Ecuador.

2 Data Analysis and Problem Statement. Case Study in Quito Nowadays a small amount of work is dedicated to solving the problems of constructing optimal routes in mountainous areas. Authors in [1] proposed an approach to addressing the issue of routing passenger routes within the framework of the mountain city of Covilha. In [2], the method of routing in a city road network in a mountainous area based on macroscopic and microscopic data is presented. It should be also noted that to date, there are no works that address the issues of optimal routing of goods delivery in mountain cities, taking into account the nonstationary dynamics of traffic flows, associated with the peculiarities of the functioning of the URN cities in mountainous terrain. In this paper, we propose a method for constructing optimal routes for the delivery of goods on URN, which takes into account the peculiarities of the non-stationary dynamics of traffic flows in the conditions of mountainous terrain. In this paper, we propose a method for constructing of optimal routes for the delivery of goods on URN, which takes into account the peculiarities of the nonstationary dynamics of traffic flows in the conditions of mountainous terrain. This method is based on the use of the modified ant algorithm [3]. In the frameworks of the proposed method, a test simulation is carried out for the mountainous city of Quito, the capital of Ecuador. The roads in Ecuador are classified as follows [4]: Class A – Primary Roads: International trunk roads linking international boundaries, international ports or provincial capitals, Class B – Secondary Roads: Recollection of traffic from rural or urban area and linking it to the Primary Roads, Class C – Tertiary Roads and local tracks: They connect Parishes and production areas to the National Road Network. The road network of Ecuador, especially the urban route network of Quito, has undergone significant improvements in recent years, mainly due to recent investments in the country’s infrastructure, the introduction of road charges, and so on. According to the World Economic Forum, Ecuador is ranked 24th out of 138 countries in the ranking for the quality of the road network [5].

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However, according to [6] most of the territory of Ecuador (76.21%) is located in mountainous areas, namely: 31.77% – Hills, 8.83% – Low mountains, 13.45% – Midaltitude mountains, 20.77% – High mountains, 1.39% – Very high mountains. The whole road network of Ecuador is 43,200 km, of which: paved roads 8,161 km, gravel roads 23,055 km, dirt roads 12,000 km [4]. As the territory of Ecuador is mostly located in mountainous terrain, most of its road infrastructure is characterized by the presence of sections of increased steepness, curvature, limited visibility and high accident rates. Although some of Ecuador’s roads and highways have improved significantly in recent years, Ecuador’s road trips are still dangerous. Some roads are poorly serviced or damaged by heavy rains and landslides. On mountain roads, there are insufficient items of security, such as emergency barriers or safety rails. The capital of Ecuador is Quito, which is located at an altitude of 2,800 m in the narrow valley of the Andes. According to the analysis [7] of the traffic flow, public transport accounts for about 60% of all trips with trends indicating a strong growth in individual transport. The number of private vehicles has been growing by 7% every year on average throughout the last decade, aggravating the problem of congestion. One way to combat the traffic congestion of the road network was implemented, from the year 2010 onwards a strategy called “Pico y Placa” (“Peak and Plate”) [7]. The circulation of vehicles is restricted during peak hour once per week depending on the license plate. Restriction periods: 7:00–9:30 and 16:00–19:30. The whole urban road network of the city consists of roads with 3, 2 and 1 roads of traffic flow. Depending on the number of roads, the traffic flow at free traffic is 70 km/h, 50 km/h and 40 km/h respectively. A characteristic feature of the urban road network in the mountainous area is the presence of a significant number of factors that affect the ability to use it in full. Among such factors is: • Natural: earthquakes, landslides, mudflows and heavy precipitation leading to partial or complete destruction of the road; • Geographic: a large number of roads characterized by steep rise or descent (longitudinal slope) and winding (a large number of turns used to reduce the longitudinal slope).

3 Simulation of the Processes of Constructing Optimal Routes in Mountainous Cities on the Example of URN in Quito For the simulation of the processes of providing the optimal routes of delivery of goods was selected a fragment of the urban road network of Quito, as shown in Fig. 1. As known [6], the URN of the city of Quito is characterized by a large curvature, longitudinal slopes and a different number of lanes in certain sections of the network.

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Fig. 1. Scheme of the location of cargo delivery points in the URN of Quito.

The data on the distance between the points of delivery of goods, the average speed of vehicles on the URN in Quito in stationary conditions is given in Table 1.

Table 1. Data on the distance and the actual speed of movement between the points of delivery of the goods on the URN of Quito.

Value of distances between points, km

Item numbers

The value of the velocities of traffic flow between the points, km/h 1

2

3

4

5

6

7

8

9

10

1

0

55

63

69

57

60

65

59

64

57

2

3.7

0

50

61

42

56

50

47

54

47

3

4.5

1.3

0

60

49

70

65

68

63

56

4

5.2

1.9

2

0

58

50

57

59

61

55

5

5.7

2.7

2

1.4

0

51

53

57

54

57

6

5.6

2.3

1.4

1.4

1

0

43

50

55

43

7

6.5

2.7

2.2

2.1

2.5

1.5

0

40

44

40

8

6.2

3.3

2.8

2.7

2.9

1.9

0.7

0

45

44

9

5.7

3.9

3.4

3.3

3.9

3.2

2

1.7

0

40

10

6.7

4.7

4.2

4.1

4.2

3.2

2

1.7

1

0

* Under the main diagonal are the distances between the respective delivery points, over the main diagonal of the matrix - the average speed of vehicles between these points in stationary conditions.

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The addresses shown in Fig. 1 and in Table 1 correspond to the following data: 1 – Antonio Jose de Sucre Y Manosca; 2 – America Y Brasil; 3 – Mañosca; 4 – Juan Pablo Sanz 3617; 5 – Centro Comercial El Jardin; 6 – 10 de Agosto Y Mariana de Jesus 2; 7 – San Gabriel Y Alava; 8 – Fray Bartolomé de las Casas 1633; 9 – Mariscal Sucre Y Bartolome de Las Casas; 10 – Primavera 4. The solution of the routing problem, taking into account the actual behavior of the traffic flow under the influence of natural factors (earthquakes, floods, mudflows, landslides, etc.), will be carried out with the help of the modified ant algorithm [3]. According to [3], we will consider the URN as a dynamically two-way oriented weighted graph. The lengths of the edges in this graph determine the average travel time of the vehicle in the traffic flow at certain parts of the network between the points of delivery (nodes of the graph). It should be noted that the fundamental difference between the modification of the algorithm [3] and the classical and current to date other modifications of the ant algorithm [8–11] is that in [3] the cyclic movement ant colony where the ants move with steady speeds replaced by the asynchronous movement of each ant with a certain speed. In addition, it is possible to record the results of optimization of the partly traversed path, to calculate the further route when changing the length of the edges of the graph during movement. It allows to carry out simulation of route optimization in the conditions of real dynamics of transport flow on URN, where ant agents, as analogues of vehicles, move with corresponding speeds. It is important, then, that the ant algorithm is based on the use of the effects of self-organization of the corresponding ant agents. This, unlike other methods of optimization, makes it possible for its application to describe the corresponding non-equilibrium, non-stationary transport processes and phenomena. For example, such phenomena are observed in the case of phase transitions of molecular crystals [12, 13], when considering the effects of self-organization of enterprises under the influence of external stochastic and discrete (sharp) changes in the factors of the nonlinear market environment [14], the dynamic of high-density transport flows [15]. The corresponding simulation studies on the construction of the optimal route were carried out within the limits of the traveling salesman problem according to the proposed method, for the 10 nodes that correspond to the points of delivery of the load (see Fig. 1 and Table 1). The parameters of optimization were chosen minimum time of passing the route and its length. Before the simulation of the route optimization processes in the conditions of the influence of natural factors on the dynamics of transport flows, with the help of method [3], an optimal time route for the specified 10 delivery points in stationary conditions of the traffic flow dynamics was determined (see Fig. 1 and Table 1). When constructing this route, it was decided that the traffic flow at certain sections of the URN occurs in free flow, without any complications. The cargo delivery route that has been optimally designed for such conditions is as follows: 1–2–3–6–5–4–7–8–10–9–1 (numbering of delivery points is shown in Fig. 1). At the same time, the passage of the specified route is 21.92 min, and its length – 20 km.

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In order to simulate the processes of constructing the optimal route in the conditions of non-stationary traffic dynamics were selected three sections of the URN that are part of the previously found optimal route: 1–2 (Antonio Jose de Sucre Y Manosca; America Y Brasil); 4–5 (Juan Pablo Sanz 3617; Centro Comercial El Jardin); 3–6 (Mañosca 170508; 10 de Agosto Y Mariana de Jesus 2). It is assumed that in these sections there may be sharp changes in conditions of traffic flow under the influence of natural factors (earthquakes, floods, mudflows, landslides, etc.). Each of these sections of the route is characterized by length, speed and time of passage of the plot. It is also known [7] that each of these sections is divided into fragments having a different number of lanes and, accordingly, different traffic flow velocities on them. Table 2. Characteristics of the sections of the URN of Quito, on which changes in the conditions of traffic flow under the influence of natural factors. Section

L, km T, min

Three lanes road

Two lanes road

One lane road

l, km t, min v, km/h l, km t, min v, km/h l, km t, min v, km/h

1

2

3.7

4.03

1.8

1.54

70

1.2

1.44

50

0.7

1.05

40

3

6

1.4

1.20

1.4

1.20

70

–

–

–

–

–

–

4

5

1.4

1.46

1

0.86

70

0.4

–

–

–

0.6

40

For the simulation, roads of sections of the URN were selected 1–2, 3–6; 4 to 5, which contain three lanes. In Table 2, these sections of the URN are highlighted in yellow. Natural factors, such as earthquakes, floods, mudflows, landslides, etc., can lead to these sections of the URN from partial to complete destruction of the road. The simulation of non-stationary dynamics of traffic flows was conducted in such a way as to gradually reduce the number of lanes in which the movement of vehicles is possible. Reducing the number of lanes on road will respectively increase the time of travel on these sections of URN. This, in turn, leads to a change in the passage time of the entire route. In addition, it can be assumed that with certain reductions in the average speed of traffic flows in these sections, it is possible to reconstruct the optimal routes for the delivery of goods, that is, the change in the sequence of the passage of the route points. Simulation of the construction of optimal routes under the influence of natural factors is divided into three groups: • change in the number of lanes and speed, respectively, in one of the three identified lanes of the URN route; • changes in the number of lanes and, respectively, the speed on two of the three designated lanes of the route; • changing the number of lanes and, accordingly, the speed at all three designated lanes of the URN route at a time.

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In the first iteration, a situation was simulated in which part of the road between points 1 and 2 was destroyed. Here the number of lanes decreases in the corresponding section from 3 to 2. The speed of the traffic flow decreases to 50 km/h. The time of passage of the road fragment increases from 4.03 min to 4.65 min (the average speed of the traffic flow in the entire section decreases from 55 km/h to 48 km/h). At the same time on all other sections of the route the number of lanes did not change. The route obtained after optimization has the following configuration: 10–9–1–2–3–6–5–4–7–8– 10 and the passage time is 22.54 min. As you can see, the configuration of the route has not changed. But the time of its passage increased by 0.62 min due to an increase in the passage time between points 1 and 2 (see Table 3). Similarly, the simulation of the route optimization process was carried out for all subsequent iterations. The number of lanes in the corresponding of URN sections 1–2, 3–6 and 4–5 was successively reduced due to the destruction of these lanes under the influence of natural factors. The results of simulation of the process of constructing optimal routes taking into account the change in the speed of traffic flow on the corresponding sections of the URN are given in Table 3. Table 3. Results of simulation of the processes of constructing optimal routes. Iter. 1 2

4-5, km/h 70

10-9-1-2-3-6-5-4-7-8-10

Change route 22.54 no

70->50

70

10-9-1-2-3-6-5-4-7-8-10

22.40

1-2, 3-6, km/h km/h 70->50 70 70

Optimal Route

T, min

70

70

70->50

3-6-5-4-7-8-10-9-1-2-3

22.26

no

4

70->40

70

70

3-2-4-5-6-7-8-10-9-1-3

22.71

yes

5

70

70->40

70

1-9-10-8-7-6-5-4-3-2-1

22.61

yes

6

70

70

70->40

3-6-5-4-7-8-10-9-1-2-3

22.56

no

70->50 70->50

8

70->50

70

10-9-1-3-2-4-5-6-7-8-10

22.71

yes

70->50

10-9-1-2-3-6-5-4-7-8-10

22.88

no

9

70

70->50 70->50

70

10 70->40 70->40 11 70->40

Х Х

3-4-5-6-7-8-10-9-1-2-3

22.95

yes

70

3-2-4-5-6-7-8-10-9-1-3

22.71

yes

Х Х

Х Х Х

70->40

4-2-3-1-9-10-8-7-6-5-4

22.88

yes

1-2-3-4-5-6-7-8-10-9-1

23.25

yes

13 70->50 70->50 70->50

3-2-4-5-6-7-8-10-9-1-3

23.05

yes

Х

Х

14 70->40 70->40 70->40

3-2-4-5-6-7-8-10-9-1-3

23.35

yes

Х

Х

15 70->40 70->40 70->0

5-6-4-2-3-1-9-10-8-7-5

23.68

yes

Х

Х

70

4-5

Х

70->40 70->40

12

70

3-6

no

3

7

1-2

Х

Х

Simulation Processes of Construction of Optimal Routes

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4 Results and Discussion Based on the results of simulation of the routes optimization processes, taking into account changes in the dynamics of traffic flows, due to the possible negative influence of natural factors on the structural characteristics of the URN, a number of features were identified in the construction of optimal routes for the delivery of goods. Thus, when changing the number of lanes from 3 to 2 at the fragment of one of the selected sections (1–2, 3–6 or 4–5), respectively, the speed of the traffic flow decreases from 70 km/h to 50 km/h. Here, the optimal route does not change, but the passage time of all points of the route increases for a time that corresponds to an increase in travel time in selected sections of the URN (see Table 3, iterations 1–3). When changing the number of lanes from 3 to 1 on the fragment of one sections 1–2 or 3–6, the optimal route is restructured as a result of reducing the speed of the traffic flow in these sections from 70 km/h to 40 km/h (see Table 3, iterations 4–5). For a section URN 4–5, the reduction of the speed of up to 40 km/h does not lead to a restructuring of the optimal route, which can be explained by the short length of the three lanes sections of this site (see Table 3, iteration 6). The next step in simulation processes of constructing optimal routes was to change the speed of traffic flow on two sections simultaneously. Thus, the reduction of the lanes from 3 to 2 in the corresponding fragments of two sections of URN 1–2 and 3–6 leads to a decrease in the traffic flow velocity in these sections from 70 km/h to 50 km/h. The simulation results show that with such changes there is a reorganization of the optimal route, where the received route does not already contain these sections (see Table 3, iteration 7). When simultaneously changing the number of lanes from 3 to 2 in the corresponding fragments of two sections 1–2 and 4–5 and reducing the speed to 50 km/h, the optimal route remains the same as during the iteration 2. However, this increases the time of passing the route (see Table 3, iterations 8, 2). With a decrease in speed at sections 3–6 and 4–5 up to 50 km/h at the same time, we obtain a new optimal route in which the site 3–6 is removed, and 4–5 remains (see Table 3, iteration 9). In the next iteration 10, we change the number of lanes from 3 to 1 in the corresponding fragments of two sections of the URN (1–2 and 3–6) at the same time. The speed of traffic flow here decreases to 40 km/h, which leads to an increase in the passage time of these points. As a result, we have a new optimal route, which does not have the corresponding sections of URN 1–2 and 3–6 (see Table 3, iteration 10). With a decrease in the number of lanes in sections 1–2 and 4–5 from 3 to 1 at a time and the reduction here to speeds up to 40 km/h, we obtain a new optimal route (see Table 3, iteration 11). The peculiarity of the results obtained in this iteration is that section 1–2 from the route is deleted, and 4–5 remains. Similar results are obtained with the same reduced number of lanes in sections 3–6 and 4–5 at the same time (see Table 3, iteration 12). The next step in simulation processes of constructing optimal routes was the simultaneous change in the speed of movement on three section due to the reduction of the number of lanes from 3 to 1 (see Table 3, iterations 13–14). In this case, there is a

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restructuring of the optimal route, in which there are no sections 1–2 and 3–6, and section 4–5 remains. In the last iteration, a situation was considered where the number of lanes from 3 to 1 in the corresponding fragments of sections 1–2 and 3–6 (decrease of speed up to 40 km/h), and in section 4–5 destruction of all three lanes in the corresponding fragment of this section of the URN (here the speed decreases to 0 km/h). According to the results of the simulation, the optimal route is obtained, where all three studied sections of the URN are missing 1–2, 3–6 and 4–5 (see Table 3, iteration 15).

5 Conclusion A method of optimization of cargo delivery routes in the conditions of non-stationary dynamics of transport flows in the sections of road network for cities located in mountainous area is proposed. In the frameworks of the proposed method, a test simulation is carried out for the mountainous city of Quito, the capital of Ecuador. To do this, 3 sections were allocated on the Quito city road network. At each of these sections, the number of lanes from 3 to 1 was gradually reduced. The reasons for reducing the number of lanes may be both natural and geographical factors. A number of effects are detected during the simulation. These effects are related to the rebuilding of optimal routes at a decrease of average speeds of vehicles on model sections of the URN to certain limit values. Thus, with the decrease in the number of lanes, the speed of the traffic flow from 70 km/h to 50 km/h and 40 km/h respectively changed, which in most cases led to a change of the route of delivery of the cargo and the removal of the relevant sections of the optimal route. Particular attention should be paid to section 4–5, which is part of the optimal route. Here, with a decrease in the speed of traffic from 70 km/h to 40 km/h or less – this section remains in the optimal route. To extract it, it is necessary that the speed of the traffic flow decreases to 0. Only in this case, this section is not taken into account when constructing the route of cargo delivery. For solving this task we use a computer program to find the optimal route. This program was written by us in Delphi. The optimal route build with help of a modified ant algorithm. The analysis of the results of simulation studies gives grounds to consider that the proposed method allows to optimize adequately the routes of cargo delivery in the conditions of non-stationary dynamics of transport flows on the sections of URN. In the future, it can find its application in solving the problems of operational control of the transportation process in mountainous cities, namely, the formation in the online mode of the optimal routes, taking into account the real traffic on the URN.

References 1. Virtudes, A., Azevedo, H., Abbara, A., et al.: Soft mobility as a smart condition in a Mountain city. In: Materials Science and Engineering, vol. 245 (2017)

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2. Yuan, M., Cheng, W., Jin, Ch.: Road network optimization for mountainous city based on macroeconomic forecasts and microscopic simulation. Procedia Soc. Behav. Sci. 96 (2013) 3. Danchuk, V., Bakulich, O., Svatko, V.: An improvement in ant algorithm method for optimizing a transport route with regard to traffic flow. Procedia Eng. 187, 425–434 (2017) 4. Ecuador Road Network. https://dlca.logcluster.org/display/public/DLCA/2.3+Ecuador +Road+Network 5. World Economic Forum: The global competitiveness report 2016–2017. http://reports. weforum.org/pdf/gci-2016–2017-scorecard/WEF_GCI_2016_2017_Scorecard_EOSQ057. pdf 6. Briceño-Garmendia, C., Moroz, H., Rozenberg, J.: Road networks, accessibility, and resilience: the cases of Colombia, Ecuador, and Peru (2015). http://pubdocs.worldbank.org/ en/780311492653985192/P147268-LCR-RegionalStudy-with-annexes.pdf 7. Factsheet: Urban Mobility Challenges in Ecuador and Quito. https://www.sutp.org/files/ contents/documents/News/Factsheet-Ecuador-ENG.pdf 8. Karmakar, R.: Solving TSP using improved elitist ant system based on improved pheromone strategy and dynamic candidate list. MAYFEB J. Comput. Sci. 1, 8–15 (2016) 9. Stützle, T., Hoos, H.: MAX-MIN ant system and local search for the traveling salesman problem. In: IEEE International Conference on Evolutionary Computation, pp. 309–314 (1996) 10. Dorigo, M., Gambardella, L.M.: Ant colony system: a cooperative learning approach to the traveling salesman problem. IEEE Trans. Evol. Comput. 1, 53–66 (1997) 11. Mavrovouniotis, M., Changhe, L., Shengxiang, Y.: A survey of swarm intelligence for dynamic optimization: algorithms and applications. Swarm Evol. Comput. 33, 1–17 (2017) 12. Puchkovska, G.O., Danchuk, V.D., Makarenko, S.P., et al.: Resonance dynamical intermolecular interaction in the crystals of pure and binary mixture n-paraffins. J. Mol. Struct. 708(1–3), 39–45 (2004) 13. Puchkovska, G., Makarenko, S., Danchuk, V., et al.: Temperature study of resonance intermolecular interaction in normal long-chain carboxylic acid crystals using IR absorption spectra. J. Mol. Struct. 744–747, 53–58 (2005) 14. Danchuk, V.D., Kozak, L.S., Danchuk, M.V., Kravchuk, A.P.: Stress testing of business activity using the synergetic method of risk assessment. Actual Probl. Econ. 171(9), 189– 198 (2015) 15. Kerner, B.S.: The Physics of Traffic, 683 p. Springer, Heidelberg (2004)

Analysis of Quality of Car Rental Services Following Example of “Citybee” Kristina Čižiūnienė1(&) and Rolandas Vitkūnas2 1

2

Vilnius Gediminas Technical University, Plytinės str. 27, Vilnius, Lithuania [email protected] International School of Law and Business, Laisvės ave. 58, Vilnius, Lithuania [email protected]

Abstract. This article analyses the quality of car rental services, analysing quality criteria of car rental services. A survey of respondents was conducted on the basis of services provided by a car rental company established in Vilnius, the Republic of Lithuania, aiming to identify car rental criteria and to determine their importance. The article presents the survey results and their analysis, also providing conclusions and a list of references. Keywords: Car rental


Service quality

1 Introduction Car rental has become a high demand service popular both throughout the world and in Lithuania. A car is a vehicle often used by people today to meet their daily needs without giving any thought thereto. Demand for rental car services has also been growing. Such services are necessary to meet transportation and travel needs if a person does not have a car. Car rental companies, like any other companies existing in the market, face increasing competition. The changing business environment obligates to continuously improve the quality of the services provided, thus retaining a competitive advantage. Expectations of organizations providing services and customers become an important criterion in the analysis of the provision of car rental services. Service quality depends on the matching/mismatch of these expectations. Since ensuring service quality for customers has become one of the key criteria of competitive advantage and successful activities, car rental companies have to periodically investigate and improve the quality of their services in light of the continuously changing user needs and expectations, which allows stating that in order to remain competitive, companies have to consider service quality assessments. Usually, before making decisions, car rental companies rely on a biased and subjective opinion rather than on analysed objective decisions. It should be emphasized that in the process of the assessment of the service quality, companies should take into account the results of an objective research. Such research allows learning much more relevant information than subjective assumptions.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 122–131, 2020. https://doi.org/10.1007/978-3-030-38666-5_13

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2 Models for the Assessment of Service Quality and Their Criteria With customers becoming more and more demanding, companies have to try to serve them impeccably. Each company must know and understand the user approach to service and to find out customer opinions for quality improvement purposes. According to observations made [5, 8], service companies have finally realized what production enterprises understood long time ago – quality will not improve if there are no assessments and research thereof. Various research models widely applied throughout the world at this time combining the theory and practice have been used to this end. According to [1], a service quality assessment model is a system the use of which allows considering only the most important and influential criteria affecting quality. Some authors [2–5, 7] unanimously agree that, depending on their nature, models can be divided into three groups illustrated in Fig. 1

Fig. 1. Classification of models for the assessment of service quality (created by authors).

Currently, there is a number of models assessing service quality presented in scientific literature, which are very similar to each other but yet different [1]. Systemized quality assessment models widely used throughout the world (see Table 1), which helped to obtain the assessment of the quality of the service being analysed by analysing user opinions. The information presented in the Table 1 above allows stating that literature provides an abundance of models for assessing service quality, and their abundance reveals the complexity and significance of the assessment of service quality. The said models define the service quality and its assessment differently due to the fact that, as per observations made by Šimkus et al. [9], researchers of service quality discuss and cannot come up with a unanimous opinion, which quality assessment model is the most objective, best reflecting the quality perceived by the user and providing most opportunities for its improvement. Thus, authors researching service quality reveal different aspects that may be important in researching quality.

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K. Čižiūnienė and R. Vitkūnas Table 1. Service quality models and their essence.

Quality model A. Parasuraman, V. A. Zeithaml and L. Berry (1985) – model of service quality gaps

Essence of the quality model Two factors shape quality: the user and the service provider. The model reveals how various gaps in the service provision process can affect the user’s perception of quality E. Gummesson (1987) - 4Q quality model The quality perceived by the user affected by user expectations, experience and image of the service provider, and the 4 key sources determining the quality: design, production, presentation and relations Quality model by A. Mayer and R. User contribution and 4 quality components, Mattmuller (1987) namely, the quality of potential service provider, user, process and the outcome, affect the quality B. Edvardsson and B. O. Gustavsson (1988, This model helps analyse quality errors and the 1990) – assessment model emerged problems, revealing areas, factors, structures and processes that should be modified A. Brogowicz, I. Delen and D. Lynth (1990) The concept of technical and functional quality – summarized service quality model is at the centre of the model, supplemented with quality gaps, dimensions and factors affecting its perception Ch. Gronroos (1990) – overall perceived The overall quality is characterized in two service quality model dimensions: technical (what the user receives from the service) and functional (how the service is provided) W. Muller (1993) – quality model This is a personal assessment of service quality of users till the use of the service, during its use and after the use R. Norman (1994) – model of faulty and Service quality depends on mutual satisfaction positive circles of the client and the service provider as well as on employee motivation

When it comes to the models listed in Table 1, the model of service gaps, also known as Servqual model, developed by foreign researchers A. Parasuraman, V. A. Zeithaml and L. L. Berry has been widely used throughout the world nowadays. According to this model, the user and the service provider shape quality. Service quality is a gap between the service quality, which the user would like to receive, i.e. the expected service, and the quality, which, in the perception of the user, he received – the so-called experienced service. The developers of this model name the perceived quality as the user’s opinion on the overall correspondence of products or the provided services as well as expectations and needs. This is why a quality assessment tool, the SERVQUAL methodology, is used to assess the quality of the provided services quantitatively. This model has been recognized the best and has become a standard in the past twenty years. According to [1], the Servqual methodology was developed based on the approach that the users’ perception of service quality is the most important. This quality

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assessment method, even though it is quite simple, effectively reveals the advantages and disadvantages of the quality of the services provided. According to [3], this methodology was designed to assess the perceived service quality at a certain time, regardless of the general process of its formation. Thus, this methodology focuses on how the user perceives a quality service. According to [1], “this methodology may be used to measure the quality of different services, because very few organizations operating in the service sector can be characterized by such exceptional qualities, which the parameters of this methodology cannot reflect”. The Servqual quality assessment criteria or dimensions include: reliability, response, competence, accessibility, helpfulness, communication, confidence, security, familiarity (understanding customers) and tangibility. It is also important to emphasize that the above-mentioned methodology has a very simple structure, which allows assessing aspects that affect service quality in order to help companies to set goals and improvement priorities in pursuit of the best results. Although the universality of the Servqual methodology has been heavily criticized, it still is considered the main scheme for various assessments of service quality. If necessary, this methodology can be supplemented with situation-relevant criteria. The quality assessment criteria allow assessing the quality and defining it as bad, average or excellent. In 1992, J. J. Cronin and S. A. Taylor created a SERVPERF model based on the Servqual methodology, which is a simplified modification of Servqual. The Servqual method assesses the perceived service quality in comparison with the expected quality, while the Servperf method assesses the perception of the quality of the service received only. The Servperf model consists of 22 aspects of perceived quality and it does not analyse user expectations whatsoever.

3 Service Quality Gaps and Remedies Assurance of service quality is a rather complicated process, the complexity of which is affected by the changing experienced quality of services and the way employees provide services. It must be admitted that the implementation of this is not easy due to the increasing rotation of employees in the service sector. Employees lack the necessary qualifications, and thus the provision of services is of poor quality. As a result, customers are less satisfied with services. When a service is provided to a customer, user expectations are less tangible, because expectations are affected by the behaviour of the servicing employee, the quality of service itself, the environment and other criteria. According to [6], all areas of operations of companies are organized and improve in light of the quality strategy. The areas of operation of companies require different actions in order to improve the service quality. Thus obviously all the services provided must be subject to high-quality standards, but often there are various gaps in the assurance of service quality, which result in consumer dissatisfaction with service quality.

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In the assessment of service quality, certain quality gaps become apparent, and they can be characterized as follows: • Knowledge gap is understood as the knowledge (planning) that service providers have about user expectations and the difference between actual customer needs and their expectations. • Gap in standards is the difference between management’s understanding of user expectations and the implemented service provision quality standards. • Presentation gap is the difference between certain service provision standards and actual provision of services by the service provider. • Gap in internal communication is the difference between what the company believes to be product properties, performance or a service quality level and what the company can actually offer to users. • Gap of perception is the difference between what was actually provided to the user and what he perceives to have received. • Gap of interpretation is the difference between promises made by means of communication of the company and what users believe to have actually been promised. • Service gap is the difference between user expectations and their perception of the actually provided service. Some researchers [1, 10] offer solving the identified gaps in quality in application of respective remedies. They believe that having noticed discrepancies between user expectations and the supplier’s ability to understand them, the following is recommended: improving communication between managers and customer service staff; reducing the number of levels in the management system; through direct communication of managers with users; hearing out users and clearing up what they expect from the service, what are their goals and needs.

4 Research of the Service Quality in the Car Rental Company “CityBee” CityBee is a company established in the city of Vilnius in 2012, which provides car and bicycle rental services. In 2013, attempts were made to also develop car sharing activities in Kaunas, but they were unsuccessfully. A repeated attempt to develop this service in Kaunas in 2016 was successful, and as from 2017, the services have also been provided in seaside resorts of Lithuania: Klaipėda, Nida and Palanga. The main users of the services provided by CityBee are residents of Lithuania and visiting tourists, who are 18 to 65 years old and earn the lowest, average or the highest income. Thus, car rental services provided to the market are affordable to both lowincome and wealthy residents. CityBee offers a fleet of cars designated to meet the needs of customers with different needs and income level, which differ in price, vehicle class, have a mechanical or automatic gearbox, air conditioning, USB connection, a spacious luggage compartment and more – and these are only the key service benefits offered to users. Currently, the offered cars are divided into four groups: practical, comfortable, cargo

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and luxury. Thus the company uses a differentiated marketing strategy having selected cars in light of the needs and expectations of each segment of users. Car stations are set up at the busiest points of cities, so customers can easily access the rented CityBee cars. The services market should focus on improving the quality of services. Therefore, finding out how customers assess the quality of services provided, what their expectations are and what factors affect them is important. This research assessed the quality perceived by customers of the car rental company CityBee in application of the Servqual quality assessment model dimensions (criteria). In order to see quality improvement opportunities in CityBee, respondents were asked to assess the criteria describing the quality of the services provided by the company: their tangibility – obviousness, response, competence, security, communication, reliability, helpfulness, and familiarity (understanding) of users. Each dimension was broken down into the respective attributes of that criterion, i.e. statements corresponding to the essence of the criterion. This model was chosen as the most popular service quality assessment model. Research Methods. A quantitative research method was used to conduct a survey of respondent opinions and a direct survey using a standardized questionnaire was used to collect data. This method of collecting data was chosen because of a survey being one of the most popular methods of empirical research; the standardization of questions ensures the comparability of measured variables in the population. Sample. Non-random (targeted) selection of respondents using the convenience method was used to carry out the research. In the targeted selection, the respondents, who were able to provide meaningful information about the researched object - customers using the services of the car rental company CityBee – were interviewed. The method of convenience allowed selecting respondents, who can be easily located and are nearby – live in Vilnius. Thus, the general sample was residents of Vilnius. On 1 January 2018, there were 635,886 residents living in the capital district (according to the Department of Statistics), of which 151,660 people were under 18 years of age and 136,278 were older than 65, thus there are 347,948 drivers, who could potentially rent a car. The research sample was calculated according to the Paniott formula (1): n¼

1 D þ 2

1 N

;

ð1Þ

where n – the necessary number of respondents; D – tolerance (recommended 0.01– 0.04); N – total number of members of the totality. n¼

1 0; 042 þ

1 347948

; ðrespondentsÞ:

When N = 347, 948, the calculated research sample is n = 400, however, respondents were very passive, and only 202 of them were interviewed.

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The reliability of demand is calculated according to the formula (2): rffiffiffiffiffiffiffiffiffiffiffiffiffi 1 1 þ D¼ n N

ð2Þ

The degree of the statistical reliability of the conducted research is calculated according to the formula (3): P ¼ 1  D; rffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi 1 1  ¼ 0:0703391; D¼ 202 34798 P ¼ 1  0:0703391 ¼ 0:929

ð3Þ

The statistical degree of reliability of the conducted research is 92.9%. 61.88% of the respondents having participated in the survey were men and 38.61% were women, of whom pupils accounted for 9.90%, students – for 23.3%, the employed accounted for 46%, housewives – for 5.94%, unemployed persons – for 10.9% and pensioners – for a mere 3.96%. The majority of respondents were 25–29 years old (32.2%) and 30–39 years old (24.3%). A somewhat smaller share (19.8%) of respondents indicated they were 40–49 years of age, 17.8% were 18–24 years old and 5.94% – 50–59 years of age. The research results reveal that users rent cars offered by the company at a significantly varying frequency. Still, most often respondents used the services of the company several times per month (42%). Usually, participants in the survey rented cars for the period of time of about 1 h (38.1%) and shorter (26.2%). In order to identify the opportunities of improvement of the quality of the services provided by CityBee, respondents were asked to assess the criteria of the Servqual model describing the quality of the services provided by the company, namely: the tangibility/obviousness, responsiveness, competence, security, communication, reliability, accessibility, helpfulness, and familiarity (understanding) customers. The criterion of confidence was not included in the research, because the manifestations of reliability and confidence criteria are very similar thus avoiding repetition of statements in the questionnaire. In the survey, each dimension was broken down into the manifestations corresponding to each of the criteria listed above. During the research, respondents were asked to rate statements related to these criteria, with 1 being “absolutely unimportant”, “very bad”, and 5 – “I absolutely agree” or “very good”. In the analysis of the results of the assessment of the above mentioned statements, the 5 closest results are rated as excellent and are considered ideal quality. The results of the research revealed that users were not satisfied with the response of CityBee in the provision of services. The assessment of all the statements disclosed a gap between expectations and actual experience: the highest gap (−1.98 points) was observed in the assessment of the response to the problems emerged, and the lowest (−0.72 points) was noticed in assessing the speed of the possibility to order services, because no contracts must be concluded. In order to meet the need of fast resolution of

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problems of customers, the company should take into consideration the gap existing in the problem solving. In case of emergencies, customers should be served as soon as possible, otherwise the image and reputation of the company may suffer severely. The research revealed that the knowledge and skills of CityBee’s staff and the necessary answers to customer questions were rated the best. Meanwhile, the respondents identified the inability of staff to provide accurate and correct information, and their failure to react to the comments made as the major gap in the competence of the company’s staff. In the assessment of these statements, gaps between expectations and the actual experience received −1.98 and −1.82 points, respectively. Thus, customers can be said to be dissatisfied with the competence of employees in answering questions accurately and correctly. Customers also believed their feedback to be ignored. The survey revealed that the language which staff used was clear without any technical jargon and exceeded customer expectations. There was an obvious 0.36 point advantage of experience of the quality received versus the expectations. These results allow stating that service quality from the communication perspective is relatively high. Meanwhile, when assessing the ability of staff to communicate in the language spoken by customers, the highest overall gap (of −2.38 points) was observed. The company should pay attention to foreign language skills of its employees. When evaluating the accessibility, respondents were presented with seven statements reflecting the essence of this dimension: the creation of uniform conditions for all users; having become a client of the company, a possibility to use the services every time when they are needed without any additional registration; fast, simple process of ordering car rental; simple contacting of the company by phone, online or in person; a possibility to get help 24/7 in case of an emergency; conveniently located parking stations; the possibility to pick up a car in one city and to leave it in another. The results revealed that the possibility to pick up a car in one city and to leave it in another offered by the company exceeded customer expectations. The obvious advantage of the quality received over expectations totaled 0.44 points. Meanwhile, simple contacting of the company by phone, online or in person was rated the worst, resulting in the overall gap of −1.72. Customers seem to have trouble contacting the company and engaging in a dialogue, if necessary. The research revealed that even though the possibility to use cars in every city was seen as very positive, customers lack means to contact the company when they face some problems. When assessing the criterion of familiarity and understanding of customers, respondents were presented with six statements related to customer preferences and cost-to-quality ratio of services: drivers having less than two years of driving experience can rent a car; children and pets can be carried in a car; there is a wide range of offered car models; no need to worry about car cleanliness and maintenance; no additional CityBee service usage fees; no need to pay for fuel to CityBee (the price of fuel is included in the rent and is not distinguished). In the assessment of the statement that customers do not need to worry about car cleanliness and maintenance, the overall rating of quality exceeded customer expectations. The quality received obviously outweighed expectations by 0.35 points, meanwhile the assessment of the statement that customers do not need to pay for fuel

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revealed the highest gap of −1.42 points. The research data allow stating that there are no significant quality problems from the perspective of familiarity of customers. The research revealed that 26.2% of respondents did not face any problems when using CityBee” services, while the remaining 73.8% of respondents faced one or another problem. The questions on reasons having led to the problem was answered by respondents having ended up in a problem situation only (Fig. 2). The majority of them named several problematic situations.

Fig. 2. Problems, which respondents faced when using the services provided by CityBee.

5 Conclusions 1. The results of the research revealed that the most common problem faced by CityBee customers was “rude communication of the company’s staff” (57.9%) followed by “staff fails to always provide accurate and correct information” (46%) and “incorrect invoices” and “written service-related information is not always clear” ranked third (with 42.1%, respectively). Even though 26.2% of respondents agreed with the statement “disregarded customer needs”, it still is important to take the fact that customers see this aspect as a problem in CityBee’s service quality into consideration. 2. Problems of technical nature relating to car locks, the e-app that is often faltering or down, cars damaged by other users, etc., are also quite frequent. 3. The research results allow concluding that when it comes to the assessment of CityBee service quality, it is mainly related to the behaviour and competence of the company’s staff. Even though customers face problems with cars or their equipment, customer service-related problems in particular prevail.

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References 1. Bagdonienė, L., Hopenienė, R.: Paslaugų marketingas ir vadyba [Service Marketing and Management]. Technologija, Kaunas (2009) 2. Jakštaitė, G., Varnauskas, M.: Paslaugų kokybės modeliai [Models of Service Quality]. Kauno technologijos universitetas, Kaunas (2014) 3. Kinderis, R., Žalys, L., Žalienė, I.: Paslaugų kokybės vertinimas viešbučių versle [Service Quality Assessment in Hotel Business]. Ekonomika ir vadyba: aktualijos ir perspektyvos 1 (21), 86–100 (2011) 4. Pena, M.M., Santos da Silva, E.M., Tronchin, D.M.R., Melleiro, M.M.: The use of the quality model of Parasuraman, Zeithaml and Berry in health services. Rev. Esc. Enferm. US 47(5), 1227–1232 (2013) 5. Poškutė, V., Bivainienė, L.: AB, “Šiaulių bankas” paslaugų kokybės vertinimas [Quality Assessment of Services in “Šiaulių Bankas”]. Ekonomika ir vadyba: aktualijos ir perspektyvos 3(23), 55–64 (2011) 6. Ramanauskienė, J., Gargasas, A.: Kokybės aktualumas kaimo turizmo verslo vadyboje [Quality Relevance in Rural Tourism Business Management]. Vadybos mokslas ir studijos – kaimo verslų ir jų infrastruktūros plėtrai 10(3), 93–100 (2007) 7. Serafimas, D.: Kokybės vadybos teorijos praktinis taikymas [Practical Application of Quality Management Theory]. Vilniaus universitetas, Vilnius (2011) 8. Shang, R.A., Chen, Y.C., Liao, H.J.: The value of participation in virtual consumer communities on brand loyalty. Internet Res. 16(4), 398–418 (2006) 9. Šimkus, A., Mikalauskas, R., Alekrinskis, A., Bulotienė, D.: Rekreacinių paslaugų kokybės vertinimas: regioninio parko atvejis [Quality Assessment of Recreational Services: Case of Regional Park]. Reg. Form. Dev. Stud. 2(16), 89–103 (2011) 10. Urban, W.: Customers experiences as a factor affecting perceived service quality. Ekonomika ir vadyba 15, 820–826 (2010). http://web.ebscohost.com/ehost/pdfviewer/ pdfviewer?vid=8&hid=123&sid=240a2563-4e1a-4be4-918a-0c3ca333dc30% 40sessionmgr115

Assessment of the Interoperability of Railway and Maritime Transport in Lithuania Aldona Jarašūnienė(&), Vladislav Lagunovič, and Kristina Čižiūnienė Department of Logistics and Transport Management, Vilnius Gediminas Technical University, Plytinės 27, 10105 Vilnius, Lithuania [email protected]

Abstract. Interaction between rail and maritime transport is a priority. This interaction can be distinguished when transport distances are greater than 300 km. When analyzing the interaction between rail and maritime transport it is important to pay attention to the essence, benefits and need of this synergy. However, there are some problems in various areas that are being tackled by organizing a sustainable transport system. These are different technical, legal, departmental and other emerging issues. They need to be investigated in detail, propose solutions, and then the interaction between rail and water can be developed more effectively. In order to indicate the problems in the context of rail and maritime transport synergy it is important to make questionnaire. The study of the interaction between rail and maritime transport in Lithuania is carried out in stages. In the article is presented questionnaire. Economic entities selected for the survey: railway, maritime and railways freight forwarding companies. The questionnaire is carried out in three parts, with the aim of obtaining opinions from different actors involved questionnaire. Keywords: Railway and maritime transport
Intermodal transport Interoperability
Sustainable transport system




1 Introduction Land and maritime transport routes merge in the territory of Lithuania. There are seaports, railways, public logistics infrastructure, but the potential for transport interoperability is not being exploited to its full potential, as road haulage is more prevalent, causing more environmental pollution and congestion in cities. Reducing the abovementioned problems by transporting goods on international routes can be achieved by organizing the interaction between rail and maritime transport. However, in most cases, ineffective, but convenient door-to-door, one-way road transport is used for transportation. Interaction between transport modes is analyzed by many scientists, but problem areas remain, especially with regard to Lithuanian transport. Transport is important for the economy of the country, because its functioning is related to other branch of economy. Globalization is driving international trade and economic growth, leading to increased traffic flows across Europe. Freight flows are on the rise, with the transport fleet growing and road transport in particular.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 132–138, 2020. https://doi.org/10.1007/978-3-030-38666-5_14

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The acceleration of globalization processes and the intensification of international cooperation have led to longer freight transport routes, which requires new solutions to make the most efficient use of the various modes of transport [4].

2 The Importance of Intermodal Transport in Ensuring Interoperability Between Rail and Maritime Transport The combination of two or more modes of transport is well established and regularly practiced in the freight transport business [3]. Intermodal transport can be summed up as a shipment from a shipper to a customer using two or more different vehicles, with uniform rates with billing and confidence. The main idea of intermodal transport is that the service and service prices of the modes of transport involved are combined to increase the utility of the transport system [1]. The advantages of intermodal transport are first and foremost the fact that combining the advantages of different modes of transport means a rational balance of transport costs and travel time. The harmonious integration of different modes of transport into one complex system allows synchronization of the use of transport modes and high level control [5, 9]. Intermodal transport facilitates the availability of rail and maritime transport, thus improving the efficiency of the entire freight system. For this reason, economic growth can be observed as it is linked to the demand for transport. However, from a different angle, freight transport has a negative impact on the environment, as resource losses and costs of transshipment occur [1]. It is claimed that the need for multimodal transport is expressed in terms of benefits: environmental protection, energy savings, large cargo flows [2]. One of the main reasons for using interactions between transport modes is to reduce the overall cost of freight transport [10]. International experience has shown that the integration of rail and national ports is important for improving the competitive position of ports, increasing the opportunities for efficient and sustainable land use, improving the efficiency of transport services, enabling ports to grow and interact with other modes of transport [6]. Rail and maritime transport can be distinguished as the dominant mode of transport for freight, as these modes operate in the highest energy saving mode [8]. After analyzing the researches of the world scientists’ certain problems of organizing the interaction between rail and maritime transport were identified: lack of compatibility in international communication (ports are the weakest link); wagon downtime at access points due to inadequate port infrastructure for cargo storage; lack of rolling stock due to possible damage in the port; shortcomings in technological, organizational interactions; lack of technical and administrative interaction (lack of reliability and efficiency); problems of rail traffic compatibility due to ongoing passenger and freight traffic; long documentation process. In order for the interaction to be organized in a rational way, a unified technology combining the work of freight fronts and the railway station is needed [10]. In order to optimize the efficiency of intermodal transport, the European Commission has determined that by 2030, 30% of freight transported by road over 300 km

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will be handed over to rail or maritime transport, and by 2050 to 50%. To achieve these results, seaports will be provided with rail freight and inland waterway transport. This is due to the steady growth of containerized freight transport, increasing road congestion and rising fuel prices [7].

3 Investigation of Interoperability of Rail and Maritime Transport in Lithuania In order to analyze the current situation of organizing the interaction between rail and maritime transport in Lithuania, the method of empirical research – questionnaire survey – was chosen. This method has been chosen because the data collected in the investigation process must verify the assumptions made. Therefore, when interviewing defined entities of Lithuanian transport economy, one can find out their position in relation to investigative interaction. As the object of the research is the interaction between rail and maritime transport, respondents were selected according to the type of transport and services specified in their activity. Questionnaire questions were designed to respond to rail, maritime transport, and freight forwarders. Respondents were collected from the Lithuanian Business Directory. By selecting “Transport Services”, “Forwarding”, and selecting by keyword: “Railways, Maritime”, 47 companies operating in the following areas were found, including 42 marine and railway companies involved in stevedoring, shipping, forwarding, 5 railway companies. After the sample size calculations it was found that if the population size of 47 respondents was chosen, choosing 95% probability and error equal to 10 would require 32 respondents. According to the established criteria, a list of respondents who are eligible to participate in the study was drawn up. It was found that 29 respondents would participate in the survey. This number is almost the same as the previously set sample size.

4 Research Results During the research, respondents were asked which rail freight unit is mostly used by railway companies. Respondents pointed out that containers are mostly used by 18.9%, less wagons, semi-wagons, tank wagons – 13.5%, and less platform, universal, coated wagons are used – 10.8%, the least respondents use special wagons – 8.1%. From this it can be concluded that the railways use containers that are not only easy to transport, but can easily be reloaded into another vehicle. Maritime carriers companies have indicated that they often use dry cargo ships for cargo transportation – 42.9%, at least uses specialized dry cargo vessels (refrigerators, ro-ro, balers), loading vessels (tankers, gas transportation), combined cargo – 14.3% of respondents chose these types of ships. Also, 14.3% of respondents indicated another response and indicated containers. It can therefore be argued that the majority of maritime carriers use vessels designed to carry containers, which contributes to intermodality.

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Therefore, the research was aimed at finding out the opinion of the respondents about the spread of railway and maritime transport interaction in Lithuania in the transportation of cargo. The results of the study showed that the interaction of rail and maritime transport in Lithuania is only partially developed. However, it is important to keep in mind the factors that influence the interaction between these modes of transport (see Fig. 1).

The lower cargo transportaon costs

10.7% 25%

The ability to carry a larger quanty of goods

17.9% Customer request

Simpler state border crossing procedures 21.4%

25% Decrease in social costs

Fig. 1. Factors determining the organization of rail-maritime transport interoperability.

The main factors noted by respondents to organize the interaction between rail and maritime transport, the lower costs of freight transportation and the possibility to carry more cargo, the answers were the same, 25%. It was also pointed out that at the request of the clients, the organization of interaction is carried out, which was indicated by 21.4% of the respondents. 17.9% of respondents pointed out that in the case of freight transport using interoperability, there are simpler border crossing procedures. And with regard to noise, congestion and reduction of emissions in cities, only 10.7% of respondents noted this as a factor in organizing interactions between transport modes. However, respondents, who did not respond to this question were asked the opposite question: what factors determine their indifference to the organization of railmaritime transport interactions. Most of the answers were –37.5% of respondents chose this option because their customers do not require. The answer was the same, with the following options: lack of necessary infrastructure, lack of necessary superstructure, long haulage, no unified information and/or legal framework for interoperability. However, it should be kept in mind that the interoperability of these modes of transport alone is not enough for the wishes of companies or customers, and that some decisions at national level have to be taken in this case. Therefore, the study aimed to find out what additional measures the state should take to promote the interoperability of rail-maritime transport (see Fig. 2).

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30%

26.5%

25% 20%

17.6%

17.6% 14.7%

14.7%

15% 10%

8.8%

5% 0% Liberalizaon Invest in the Financial Reduce rail Increase Increase road of Lithuanian development assistance to infrastructure polluon tax for road Rail Market of seaport companies ulizaon rates charges for vehicles infrastructure developing railroad transport and marime operators suprastructure interacons

Fig. 2. Additional measures to be taken by the state to promote interoperability between rail and maritime transport.

The largest share of respondents –26.5% said that it would be necessary to invest in the development of the infrastructure and superstructure of the seaport by improving the condition of access roads and railways, by acquisition of loading cranes with higher lifting capacity. 17.6% of respondents believe that the Lithuanian rail market needs to be liberalized, thus enabling private companies to engage in transportation and cooperation with maritime transport companies, and the same number of respondents believe that financial support to companies expanding research interactions will attract more interest in intermodal freight transport. 14.7% of respondents indicated that rail infrastructure utilization rates should be reduced, as in the current monopoly situation, the rates for companies are different and the lowest for infrastructure managers. The same number of respondents point to the need to increase road haulage charges and to choose less polluting transport alternatives, which is to promote co-modality, as the current situation is that road transport is predominant in freight transport. At least 8.8% of respondents believe that increasing the use of road charges could also help to improve the interoperability of transport modes. As the results of the study have shown, in this interplay of modes of transport, state intervention is necessary, not only for domestic but also transit traffic. Therefore, the study aimed to find out what role the state should play in promoting transit through the territory of Lithuania (Fig. 3). According to many respondents, the state should cooperate effectively with the transport systems of neighboring countries and create a unified transit strategy (60.4%). 16.3% of respondents believe that granting tax relief to transport companies that carry out transit transfers would increase the number of flows and similar businesses. 14% of respondents believe that a balance should be struck between state regulation and free market conditions. The lowest number of respondents –9.3% indicated that a new legal

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Effecve cooperaon with neighboring countries' transport systems

9.3%

Creang a unified transit strategy

30.2%

14.0%

Providing tax relief for transport companies

16.3% Ensure a balance between state regulaon and free market condions

30.2% Improvement of the legal framework

Fig. 3. The role of the state in promoting transit through Lithuania, taking into account the opinion of respondents.

base is needed. Also, the vast majority of respondents confirmed that investments in infrastructure of Klaipėda Seaport will have an impact on more frequent organization of rail and maritime transport interaction.

5 Conclusions 1. Analysis of scientific literature has clarified that the interaction between rail and maritime transport is being considered as part of intermodal and multimodal transport, which is of great importance for the organization of a sustainable transport system. However, interaction between rail and maritime transport still has some problems: lack of compatibility in international communication; shortcomings in technological, organizational interactions and etc. 2. The study of the interaction of rail and maritime freight transport in Lithuania, carrying cargo on international routes, showed that the provision of this service lacks the customer’s need, smooth and fast organization of the work process, as well as the positive attitude towards to the intermodal benefits. 3. In order to ensure the full organization of freight transport by rail and maritime transport, it is necessary to have an interest in the parties involved in the freight transport process, to provide more information on the interplay of money on the Internet and on social networks; to organize trainings, seminars, conferences on collaborative interoperability issues and to collaborate on joint sustainable transport projects; review the proposed transportation rates and provide more money to loyal customers, thus increasing the popularity of infrastructure and transport. 4. It is important to create the demand for organizing the interaction between rail and maritime transport; to encourage more companies and private individuals involved in organizing research interactions in freight transport and to provide better loan facilities to finance related projects.

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References 1. Behrends, S.: The significance of the urban context for the sustainability performance of intermodal road-rail transport. J. Elsevier. Procedia Soc. Behav. Sci. 54(2012), 375–386 (2012) 2. Beškovnik, B., Twrdy, E.: Green logistics strategy for South East Europe: to improve intermodality and establish green transport corridors. Transport 27(1), 25–33 (2012). ISSN: 1648-4142 3. Crainic, T.G., Kim, K.H.: Intermodal transportation, Canada, 81 p. (2005) 4. Filimanavičienė, A.: Krovinių pervežimai geležinkeliais, jūrinių ir kelių transportu: sąveikos, privalumai, galimybės. Žurnalas “Transporter Railways” 1(23) (2014) 5. Jaržemskis, A., Jaržemskis, V.: Krovininis transportas, 264 p. Technika, Vilnius (2014) 6. Komisijos komunikatas tarybai, Europos Parlamentui, Europos ekonomikos ir socialinių reikalų Komitetui ir regionų Komitetui. Krovinio transporto logistika – tvariojo judumo pagrindas. Briuselis. KOM, 336 galutinis (2006) 7. Leal Matamala, E., Perez Salas, G.: Port-rail integration: challenges and opportunities for Latin America. Bulletin FAL. no. 310, 11 p. (2012) 8. Mortimer, P., Ribeiro, J., Kula, P., Balik, S., Mistodie, O.A.: Design of integrated and coordinated multimodal transport systems – North sea – Mediterranean corridor. Transp. Probl. 9, 71–88 (2014) 9. Muller, G.: Intermodal freight transportation. Eno Transportation Foundation, Inc., New York (1999) 10. Rodrigue, J.P., Comtois, C., Slack, B.: Geography of Transport Systems, 284 p. Routledge, Abingdon (2010) 11. Šakalys, R.: Intermodalinių terminalų sąveikos tarptautiniuose transporto koridoriuose tyrimas. Vilniaus Gedimino technikos universitetas (2013) 12. Пpaвдинa, H.B.: Tpaнcпopтнoe oбecпeчeниe кoммepчecкoй дeятeльнocти. [Transportation support of commercial activities]. Ульянoвcк: УлГTУ, 95 c. (2007) 13. Coкoлoв, A.A., Coлoвьёв, A.A.: Ocнoвы взaимoдeйcтвия жeлeзнoдopoжнoгo и вoднoгo (мopcкoгo) тpaнcпopтa (нa пpимepe Mypмaнcкoгo тpaнcпopтнoгo yзлa). [Fundamentals of interaction of railway and water (sea) transport (for example, the Murmansk transport hub)]. Becтник MГTУ. Toм 18 no. 1, 48–52 c. (2015)

Modernizing of the Rail Transport Curriculum and Study Process Enno Lend(&) and Wladimir Segercrantz Institute of Logistics, TTK University of Applied Sciences, Tallinn, Estonia {enno.lend,wladimir.segercrantz}@tktk.ee

Abstract. In recent years, the European Commission has raised the question of how to improve the market position of rail transport. The key success factors beyond the development of rail transport infrastructure are safety (control and command systems of rail traffic), opening the rail transport market to competition and improving the interoperability. A holistic approach to these issues will certainly help to solve the complex problems, but more attention at present should be paid to the development of railway education, including professional higher education. The modernized curricula and more integrated competences are definitely important factors for improving the position of railway transport in the future. In this paper, the authors analyse the current situation of the railway education in Central Baltic region (incl. Finland, Estonia, Latvia) and discuss the new concepts and designs of a more harmonized and less fragmented railway education curricula. In the authors’ opinions, these results can be used to promote railway education more widely. The paper also focuses on the experience of using simulation environment in study process. The paper is based on the study reports of the Interreg Central Baltic Programme 2014–2020 Project EDURAIL-Harmonized and Modernized Multidisciplinary Railway Education, Interreg Programme for Central Baltic [8]. Keywords: Railway transport
Modernized curricula of railway engineering
Simulation in railway education
E-learning

1 Introduction Rail transport is the economic sector encompassing the rail transport of goods and passengers, as well as railway asset management, legislative framework, opening markets for rail cargo and passenger markets; and also related curricula and R&D activities, which is supporting the development and sustainability of these issues. In this paper, the authors analyse the current position of rail transport in Finland, Estonia and Latvia and make suggestions for improving railway related (professional) higher education, thereby improving the competitiveness of rail transport in the future. As the rail transport business and also the railway traffic management have been historically poorly harmonized, the same trends have been dominating in the field of rail transport education. Much of the overall problem in goods transportation in Europe is focused on railway transportation. It is a comparatively old transport sector (about 150 years) that has decreased in various aspects over many years [1]. Cross-border cooperation of © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 139–150, 2020. https://doi.org/10.1007/978-3-030-38666-5_15

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higher education institutions enables to achieve the necessary methodological strength to develop integrated approach to railway education and support the regional railway enterprises to pave the way to the European Railway Area. The main objective of this paper is to elaborate on the methodological approach for less fragmented, innovative and more competence based (professional) higher education for railway sector. The paper is prepared by using the results of the project EDU-RAIL, the leading partner of the project was TTK, and the project partners were TSI, RTU, HAMK and KRAO1. This paper is by nature an applied research, which encompasses the new methodology for designing curriculum, using e-learning, cross-study and simulators possibilities for railway education.

2 National Railway Sectors of CB Region (Finland, Estonia, Latvia) Today’s geopolitical situation and the EU’s Trans-European Transport Network’s (TEN-T) regional initiative Rail Baltic are linking the region’s railway sector’s needs closer together than ever. Due to the cross-border nature of railway transport and the joint need of regional enterprises for further integration with European Railway system, the project aims to reduce fragmentation of railway education and R&D in the region. About 10 years ago, Enarsson has mentioned that railways in Europe are today an undeveloped transport market, neither deregulated nor harmonized [1]. The primary reason for this is that there exist so many different conditions when it comes to electrical power suppliers, signalling systems, track conditions, operating rules, driver training and language difficulties. Today, the market share of rail transport in Estonia and Latvia is low. The same situation can be seen in the majority of the EU countries. As noted by Briginshaw, the rail’s share of the European freight market is just 11–12%, well short of the European Union’s ambition to reach 30% by 2030 [2]. For the rail freight businesses of Estonia and Latvia, the transit services for Russia and other CIS countries are obviously important. The sea ports in these countries were developed to serve foreign trade of neighbours. Liquid and dry bulk cargo flows used to be dominating. At the beginning of the 2000s, yearly cargo volumes were increasing and this positive development was estimated to continue. The favourable situation in transit business for Estonia started to change dramatically after the year 2007. The main factor lies in Russia’s economic and political decision to use more of Russia’s own ports for transit transported cargo sent abroad with rail transport and port services, instead of using the railway and ports of Estonia. The rail freight volumes throughout the year 2015 in Estonia were 28 million tons, of which domestic shipment volume was 15 million tons (annual capacity reduction of 25%), and international operations amounted to 13 million tonnes (20% reduction). For Latvian rail sector, the impact of change of Russian transport policy was not so dramatic. Rail cargo transportation

1

TTK – Tallinn University of Applied Sciences, TSI – Transport and Telecommunication Institute/Riga, RTU – Riga Technical University, HAMK – Häme University of Applied Sciences/Finland, KRAO – Kouvola Railway and Adult Education Company.

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accounts for 52% of the total amount of cargo transported by land and this number increased until 2015. Transit transportation by rail accounts for approximately 85% of the total amount of cargoes transported by rail – mainly from the ports of Russia and Belarus to the ports of Latvia (East – West transit corridor). The Latvian rail freight transport operates in general on the East – West route, and is the largest compared to the other EDU-RAIL partner countries. Finally, it is necessary to point out that Latvian ports and transit corridors are more attractive for Russian shippers. Rail freight transport of Finland is serving mainly the needs of country’s own foreign trade and domestic industry. In 2015, the total volume of goods transported by rail was 33.4 million tonnes, while the transport performance amounted to 8.5 billion tonne-kilometres. Railway freight transport serves the forest, metal and chemical industry, as well as the transit traffic. The key types of goods are forest products and wood-based raw materials. The role of transit volumes is not so dominant as in Estonia and Latvia. The Eastern traffic is serving the Finnish own import of energy products and other raw materials for the needs of industry. The role of domestic passenger transport differs much from partners. Historically, the rail passenger transport in Finland has had an important role for local, intercity and international passenger transport. There is an overnight train service from South of Finland to Lapland. This service includes the transport of cars in the same train. Passenger train connections with Russia have been developed. For example, there is a 3-h service between Helsinki and St. Petersburg. The future Rail Baltic, when opened, will increase the international connections between partners and might facilitate the opening of the joint labour market. Taking into account the impact of railway regulations to the railway operators, “the set of railway legislation, adopted 2016, aims to remove technical, regulatory and legislation obstacles, the rail sector in development in terms of market opening, competitiveness and interoperability incl. “Technical Pillar” and “Market Pillar” [6]. In Fig. 1 shows the volumes of freight and passenger transport.

200000 150000 Finland

100000

Latvia Estonia

50000 0 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Fig. 1. Performance of rail freight transport in Finland, Estonia and Latvia in million tkm (Source: Eurostat, 12.01.2018).

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The data provided in Fig. 2 show the dynamics of rail transport of passengers in Estonia, Latvia and Finland. Passenger transport in Finland due to its large territory and connections with Russia is much bigger than in partner countries. 5000 4000 3000

Estonia

2000

Latvia Finland

1000 0 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

Fig. 2. Rail transport of passengers in Estonia, Latvia and Finland, million passengers/km (Source: Eurostat, 12.01.2018).

3 Methodological Approach for Improving Curriculum of Railway Engineering Rail companies are, in most cases, multi-service enterprises that provide different types of freight and passenger transport services. Dictated by internationalization and social needs, the higher education is currently changing from an input-output based, professor-led approach towards a more integrated competence-based student led approach, aiming at employing deep thinking to develop deep understanding of multidisciplinary concepts and environment to guarantee a sustainable growth across industrial, technological and service sectors [3]. For the development of improved study modules, qualitative research methods were used, as they enable to open the perception and understanding of a focus group by conversational communication. The main objective was to develop five multidisciplinary study modules for railway engineering. A module is a short course of study that may consist different subjects, which, together with other completed courses, can count towards particular learning outcomes needed to fulfil the requirements of the curriculum and/or acquire professional qualification. The scheme of qualitative research is given on Fig. 3. In this study, a qualitative research method was used with phenomenological study. Conducting interviews with key persons and roundtable discussions took place within the qualitative study, where participants could also clarify their positions and make preferences (Fig. 3, Interim findings I). The next part of the phenomenological study was the reading of different development plans, curriculum, projects, best practice examples and also visiting universities and educations centres, etc., regarding the railway education suppliers (Interim findings II).

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Fig. 3. Scheme of qualitative research.

As a result of the two-part phenomenological study, the content of the modules and the volumes of subjects were formulated. The semi-structured interviews focused on the following topics: • highlighting the current legal and operational environment in Finland, Estonia and Latvia to estimate the development of railway sector in the next years (next 5 years): opening of the market for passenger and freight services, competition, newcomers, etc.) in the light of railway sector employers’ necessity for the profile of engineers and VET qualifications; • exploring the impact factors for the needs of railway employers (EU level, regional, country level) about the skills of experts; • exploring how the changes in the operational environment of the railway undertakings will impact the needs of skills and profile of the above mentioned experts; • monitoring how the five multipurpose study modules, if implemented in teaching and training process, will meet the needs of employers; • outlining the name and content of module.

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As a result of national round tables and interviews, it was pointed out that the study modules should give a clear understanding of the related EU and national level safety and operational regulations. Professional knowledge related to the railway transport should include the basic professional knowledge of railway technologies and infrastructure. In the future, a common safety language might be necessary, e.g. for Rail Baltic, it would be English. Also, the dynamic nature of developing the curricula of safety related professions (train drivers, traffic controllers and dispatchers), was stressed, because of the continuous process of changing the laws and regulations. The interviews also brought out the importance overcoming language barriers and of opening up the role of cross-border safety related databases and EU covering registers of rail safety, in order to show the role of the ERA (European Railway Agency) in the process. The necessity of presenting the opening of the markets of rail freight and passenger services to competition was also highlighted. Three regional study reports (Finland, Estonia and Latvia) and the summary report were developed during the EDU-RAIL project. The study modules were defined as follows: • Module 1 “The Single European Railway Area”. • Module 2 “General Professional Knowledge and Requirements Regarding the License”. • Module 3 “Service Oriented and Intelligent Transport System in the Context of Opening Markets”. • Module 4 “Control and Command Systems of Rail Traffic”. • Module 5 “Logistic Management and Operating of Rail Transport”. An Example. Module 5. Logistic Management and Operating of Rail Transport, 15 ECTS. The aims of the module: this module is centred on the holistic transportation system and on the role of rail freight systems and their components. The module provides the knowledge and skills in field of logistics management and in the field of railway technology and management. After completing the module, the students have the systematic knowledge of the logistics and transport systems and of the operating of rail transport. The use of the study modules in different countries will reduce the fragmentation of railway engineering education and support the better understanding the EU Railway System and legislation. This module provides a common understanding of the railway system, freight transport operations, management and technology required for sustainable and intelligent rail freight system design. The content of module is shown Table 1. The developed module within the learning material is used for formal and continuing education for students.

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Table 1. The content of module: logistic management and operating of rail transport. Content of module

Guidelines by themes

1.

Role of the rail transport in the supply chain

2.

Policy and regulations in the rail transport

3.

Railway freight operations and management

4.

Railway asset management and pricing

5.

Rail environment and crew management

• Role of transport in the supply chain management • Rail transport and transport system, design of intelligent transport system • Multi- and intermodal transportation • Real-time path coordination, tracking and tracing • Standards • New generation of rail vehicles and smart infrastructure • Legislation and regulation • Agreements • COTIF & SMGS freight area • Railway system • Services and quality • Planning of International Transportation Operations • Safety and security of transportation operations • Railway asset management framework • Pricing of rail transport • Freight forwarding of rail transport • Green & sustainable rail transportation • Rolling stock selection • Training of employees • Border crossing operations (rolling stock & crew rotation)

Volume of studies 3 ECTS

3 ECTS

3 ECTS

3 ECTS

3 ECTS

The developed module, Logistic Management and Operating of Rail Transport consists of five subjects, each with a volume of 5 ECTS, and the total of module is 15 ECTS. In future is possible to increase the scope of covered subjects.

4 Use of E-Learning and Simulation Environment in Rail Engineering Education 4.1

E-Learning Environment

E-learning is a system, mode, or form of learning that relies heavily on electronic resources. E-learning can be used to complement classroom methods (lectures, in-class problem solving, face-to-face discussions, etc.) or can be the primary mode of delivery,

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where all contact is limited to interaction with online services (a learning environment or various online tools) and direct contact with instructors or other learners may or may not be foreseen. When e-learning is the primary mode of delivery, it provides the learner with a lot more control over his or her learning. The individual learner can decide by him- or herself when to learn and how much time to spend learning (engaged with some element of the online resources). If there is no active instructor or facilitator, learning can be entirely self-paced (with automatic feedback). E-learning is actually much more than making available the structured teaching/ learning materials online. Since it is in effect a tool for independent study, effective elearning also relies on the structuring of the learning process itself. This means that materials should be organized in a way which takes into account the idiosyncrasies of learning online, learning objectives should be clearly stated, and there should be activities (exercises, problems, tests, etc.) that support these objectives. Good elearning is much like a good (well-structured) textbook but goes beyond it by taking advantage of the learning opportunities provided by online “interaction” (through online activities that give instant feedback). E-learning can take many forms. It is often carried out by using a learning management system (LMS), where users need to register before accessing course materials. The use of an LMS can offer several advantages. The main advantage is that it makes it possible to track learner progress and monitor learner activity. This is important in an institutional setting, where assessment may depend at least in part on results recorded in the LMS. The ability to track one’s own progress over time across multiple activities also helps learners to engage more consciously in the learning process and more effectively focus their efforts [8]. There are, in fact, many learning management systems to choose from. Moodle was chosen in the project because of its reputation and user-friendliness: as an open-source relatively robust feature-rich LMS in wide use around the world with a very active user and developer community. Moodle is a learning platform designed to provide educators, administrators and learners with a single robust, secure and integrated system to create personalized learning environments [7]. 4.2

Use of Railway Simulators in Study Process

One part of the railway simulator is a model railway (1:87 scales) of one station of the main track (Fig. 4). This model gives a good overview to students about the functionality of station route table and the functionality of outdoor infrastructure components in station. The station model can be simulated with interconnection to the main system for creating abnormal situations, component failures and their impact to the main functionality of the entire system. With failure simulations, restrictions to traffic capacity can be evaluated, and the main activity rules in case of failures understood. It is possible to perform the following laboratory works: 1. 2. 3. 4.

interlocking system architecture and work principle; subsystem integration; interface, failure save interface; point machine and components;

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5. track vacancy detection systems functionality and function principles; 6. level crossing system functionality, architecture and integration depending on system location; 7. failures in subsystems; 8. interlocking power systems; 9. signals; 10. Hot-Box detectors system (HABD) functionality; 11. adjustment of the subsystems and restarts, rules and restrictions; 12. radio and telecommunication systems on the railway infrastructure; 13. high-speed railway. The study program in TTK University of Applied Sciences (TTK) is built up so that the beginners who have interest in railway signalling technology will get their initial knowledge and know-how of the railway automation environment. They will get the first overview of railway technology and begin to understand the practicalities of railway infrastructure. Through performing practical tasks in the laboratory, they will be introduced to the functionality of the system and the real size of railway environment. They will also learn to understand the main railway hazards and rules to avoid them.

Fig. 4. Main interlocking simulator.

For engineers, training courses at TTK offer practical knowledge about subsystem integrations, finding failures and principles of localization, as well as knowledge on dealing with general errors, principles of system upgrades and new legal regulations in Estonia and in the EU. As the main activities of a railway signalling engineer will be carried out in an electrified environment, it is required that the students of railway signalling and technology have fundamental knowledge about handling of low power electricity (Fig. 5).

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Fig. 5. Hot/box and hot wheel detector.

They must have first basic knowledge about the hazards of the electrified environment and must understand the basic rules about electro-mechanical subjects. The students who are interested in increasing their qualification should have previous practical experience and knowledge about railway signalling technology. The qualification can be raised according to the Estonian occupational qualifications system. The rise in qualification requires good knowledge about signalling roles and legal requirements, as well as of international standards like CENELLEC. The training is divided into individual and group work. Individual study usually covers the acquisition of knowledge about unplugged safety system components and subsystems, and work with drawings and documentations. The group work tasks cover practical team works on the real system and on the study process. In the simulation, it is possible to move the train to the desired location, to a signal or a mark, and to clarify why a particular signaling element is necessary. It can also be illustrated in the ALSN system, the signals of which light up in the driver’s console depending on the signals outside on the track. In addition, the simulation can illustrate the interdependence of signals. In other words, in the simulation, it is possible to see two traffic lights simultaneously and show how the traffic lights depend on each other. That is, what is the signal in a traffic light if there is, for example, a yellow signal in the next (or previous) traffic light. If the illustrative part of the simulation is in a virtual environment and with variable routes, it is also possible to display different signals of the main traffic lights (entrance and departure traffic lights) depending on the train’s route. It is also possible to explain to the students the principles of train traffic and shunting, and how the shunting work is carried out in the railway station. In addition, it is possible to play different shunting scenarios and explain why the shunting process takes so much time [6]. The outcomes of the EDU-RAIL project will be further developed by a grant of the ERASMUS+ programme for the project “Digitally Supported and Virtual Study Practices for Modern Logistic Systems”. The main focus areas of the project are:

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• digitalization. To fully benefit from this innovation, it is vital to improve curricula and study processes of transport technology towards digitalization. The education of new graduates must give them readiness to work in a new digitally supported operational environment of transport sector; • international approach. National approach will not answer the needs of the new operating environment for the transport sector of the EU. The curricula have to meet this challenge – to educate and train experts prepared to work in multinational enterprises and teams. To meet the above mentioned challenges, higher education institutions and training providers strive to develop innovative virtual study environment(s) for selected themes of logistics.

5 Conclusions This paper is focusing on the development of railway education in terms of curriculum and study environment. The nowadays technology and methods used to develop rail infrastructure, systems, traffic management equipment etc., also put pressure on the deployment of learning environment and the improvement of curriculum. The opportunities that the digitalization process and rapid technological innovation deployment bring can have a deep effect on enhancing competitiveness in various key areas - e.g. products and system solutions, skills, cost optimization, improved manufacturing, new markets, boosted productivity and performance [5]. The main results of the study were: highlighting the current legal and operational environment in the Baltic region and taking into account the development trends in the railway sector. It was found it is necessary to contribute to better harmonization of railway education: • exploring how the changes in the operational environment of the railway undertakings will impact the needs of expected competences of the railway engineers. The education of new specialists must give them readiness to work in a new digital environment of railway sector; • creation of the multipurpose study module and the using simulation tools with virtual study environment to provide the opportunity to use cross-study between different education institution. We think that above mentioned approach and topics are universal and might be interesting for other educational institutions from other countries of wider Baltic area; • taking into account the fragmentation of railway education, the authors considered to be necessary to expand cooperation in the development of study materials and development of methodological approach for e-learning materials based on Carpe Diem learning design process – to use a team-based learning design [4]. Aligned modernized study modules will significantly improve the quality and cross-border cooperation abilities of the future workforce in the railway sector and help to reduce the fragmentation of railway education. It is possible to use the results in outside of Central Baltic area – for that access to results is possible.

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Acknowledgment. The authors of this paper would like to acknowledge the EDU-RAIL project team for the collaboration and the Interreg Central Baltic Programme 2014–2020 for funding our initiative to improve the railway education.

References 1. Enarsson, L.: Future Logistics Challenges, pp. 267–268. Copenhagen Business School Press DK (2006) 2. Briginshaw, D.: Time is not on the side of European rail freight operators. Int. Railw. J. 58(8), 4 (2018) 3. Marinov, M., Faszczyk, A.: Curriculum Development and Design for University Programmes in Rail Freight and Logistics, p. 1167 (2014). www.sciencedirect.com 4. Salmon, G.: Carpe Diem - A team based approach to learning design. https://www. gillysalmon.com/carpe-diem.html. Accessed 20 Mar 2019 5. Shift2Rail Multi Annual Action Plan, Executive view, Part A. Shift2Rail Joint Undertaking, Brussels (2018) 6. Fourth railway package of 2016. https://ec.europa.eu/transport/modes/rail/packages/2013_en. Accessed 10 Jan 2019 7. MoodleDocs:Overview. https://docs.moodle.org/33/en/ 8. Harmonised and Modernised Multidisciplinary Railway Education (EDU-RAIL). http:// eprints.tktk.ee/4123/. Accessed 15 Jan 2019

Comparison of Studies of Dangerous Cargo Flow Distribution Between Rail and Road Transport Gediminas Vaičiūnas1(&), Olha Porkuian2, and Jelena Nozhenko2 1

Vilnius Gediminas Technical University, Plytinės str. 27, 10105 Vilnius, Lithuania [email protected] 2 Volodymyr Dahl East Ukrainian National University, pr. Central 59-a, Severodonetsk, Ukraine [email protected], [email protected]

Abstract. The article compares the results of different studies of dangerous cargo flow distribution between rail and road transport. The dependency has been examined by example of actual data that assesses the percentage ratio variation of transported dangerous cargo by rail and road transport when the total quantity of cargo changes by one percent. The results of this study have been compared to the results of expert survey on the issues of competitiveness of dangerous cargo transportation between rail and road transport. Keywords: Dangerous cargo
Railway transport
Road transport
Cargo flow distribution

1 Introduction Cargo transportation is one of the most popular activities and the transportation of dangerous cargo is one of the areas of this business. It has its own peculiarities of legal regulation, as well its own regularities of scale variation. The researchers usually assume that the peculiarities of transportation of these goods can be solved by interviewing the specialists involved in their transportation [7]. One of the peculiarities of dangerous cargo transportation is their flow distribution between rail and road transport. Expert opinion surveys are performed frequently in order to clarify the regularities of the said transport competitiveness during the transportation of dangerous cargo. However, it should be borne in mind that as the scale of the economy changes not only the overall level of cargo turnover but also its distribution among types of transport varies. The objective of this study is to establish the variation of dangerous cargo flow distribution between the said types of transport when the economic scale indicators change and compare these regularities with results of expert survey on the issues of competitiveness of the said transport types.

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2 Overview of Information Sources According to research data, the road transport is currently more competitive than the rail transport [2]. The researcher from Vilnius A. Bernatavičius established in its final master thesis based on expert opinion that the most important assessment criteria of rail competitiveness during transportation of oversized loads is the safety (53% significance). The least significant criteria is the delivery time (9.3%). In experts opinion, the most important criteria in rail competitiveness during transportation of dangerous loads is also safety (55%); the least significant criteria is the costs (9.1%). The researcher assessed the expert opinions comparing the road and rail transport in transportation of oversized cargo and established that the costs are lower, as well as ecology and safety are greater when transporting the cargo by rail transport. In expert’s opinion, the delivery time is shorter in transportation of cargo by road. After having assessed the experts’ opinion in comparing the road and rail transport in transportation of dangerous cargo, the researcher established that the costs are lower, as well as ecology and safety are greater when transporting the cargo by rail transport. In expert’s opinion, the delivery time is shorter in transportation of cargo by road. After having used expert assessment and multi-criteria AHP method, the researcher established that the rail transport is approximately 80% more competitive in transportation of oversized and dangerous cargo. The use of AHP method was the original solution having in mind that this method is applied to similar studies [6]. However, the deficiency of the said study is the fact that it gives very little attention to the impact of changes in economic indicators on different types of transport. The Lithuanian scientist Batarlienė offers to calculate the costs by applying the probability theory [1, 9]. However, the said study of the scientist was over without any generated solutions. A literature source offers the studies of dangerous cargo flow dependency on the quality of rolling stock fleet [4]. Some authors look for analogies of dangerous cargo flow regularity with regularities of passenger flows by assessing the reliability of rolling stock [12]. They also offer to examine the dynamics of the number of failures of rolling stock fleet to dangerous cargo similarly as in passenger rail [3, 5]. There are studies that assess the physical aspects of dangerous cargo transportation, for instance, the dynamics of carriage [8], but this is slightly different area of studies. The objective of this study is to examine how the flows of dangerous cargo directly depend on changes of economic indicators based on the example of statistical data. The formal objective of the research is to establish whether the correlation of dangerous cargo flow distribution (flow ratio) between rail and road transport with gross domestic product, percentage of unemployment and total flow of transported cargo (not only dangerous) matches with experts’ opinion about competitiveness of transport types.

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3 Methodology of the Research The distribution of dangerous cargo flow between rail and road transport can be assessed by ratio of the total transported dangerous cargo by rail and road transport (per annum): RR;A ¼

LR ; LA

ð1Þ

where LR – the amount of dangerous cargo transported by rail per annum, millions of tonnes; LA – the amount of dangerous cargo transported by road per annum, millions of tonnes. In the studies of the author created three functions of indicator RR,A based on statistical data that assess the change of gross domestic product, change of unemployment rate in the country and the change of transported cargo amount accordingly: RR;A ¼ f ðXGDP Þ; RR;A ¼ gðXU Þ;

ð2Þ

RR;A ¼ hðXL Þ: where XGDP – gross domestic product, billions of Euro; XU – unemployment rate in the country, percent; XL – total amount of transported cargo, millions of tonnes. The values of square of correlation coefficient R2 have been calculated for each of these functions. They showed that all functions actually correlate with the statistical data. Studies have shown that the total flow of transported cargo is most correlated with the ratio of dangerous goods transported by rail and road transport. Therefore, it is appropriate to investigate in further studies. Two dependencies have been developed for further studies: the dependency of dangerous cargo amount transported by rail and road transport (per annum) ratio on the total amount of transported cargo and the dependency of annual percentage change in the ratio of dangerous cargo transported by rail and road transport on the annual percentage change of total amount of transported cargo. The latter will assess the percentage change of ratio of dangerous cargo amount transported by rail and road transport, when the total amount of cargo changes by one percent. It is obvious indicator of competitiveness of the said transport types. This dependency is compared with the results of expert opinion (on issues of transport type competitiveness). Survey data were processed by AHP method.

4 Study Process The data used in the study (amount of dangerous cargo transported by rail; amount of dangerous cargo transported by road; ratio of dangerous cargo transported by rail and road transport; total amount of cargo) are provided in Table 1.

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Year

Amount of dangerous cargo transported by rail, millions of tonnes

Amount of dangerous cargo transported by road, millions of tonnes

Ratio of dangerous cargo transported by rail and road transport

2012 2013 2014 2015 2016 2017

12.31 13.63 13.02 11.57 12.99 12.68

1.399 1.535 1.712 2.03 2.16 2.893

8.80 8.88 7.61 5.70 6.01 4.38

Total amount of cargo, millions of tonnes 121.3 120.7 123.3 127.1 127.1 131

Ratio of the total amount of cargo transported by rail and road transport

Dependency graph and dependency function with calculated value of square of correlation coefficient R2 of indicator assessing the distribution of dangerous cargo flow between rail and road transport (RR,A) are prepared based on data of Table 1. The dependency of ratio of the total amount of cargo transported by rail and road transport (per annum) on the total amount of transported cargo is provided in Fig. 1. 15 y = -0.4536x + 63.635 R² = 0.9907

10

5

0 115

120

125

130

135

Total amount of transported cargo, millions of tonnes

Fig. 1. The dependency of ratio of the total amount of cargo transported by rail and road transport (per annum) on the total amount of transported cargo.

Although the chart in Fig. 1 shows the obvious regularity, such method of examination has a deficiency – the total amount of cargo is directly related to one or another country or region. The examination of relative indicators would be more correct. If the dependency assessed the percentage change of ratio of dangerous cargo amount transported by rail and road, when the total amount of cargo changes by one percent, it would propose study that is more objective. This connection is provided in Fig. 2.

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Change of ratio of dangerous cargo amount transported by rail and road transport, percent

10 y = -8.4425x + 1.1672 R² = 0.9415

0 -10 -20 -30 -1

0

1

2

3

4

Change of total amount of cargo, percent

Fig. 2. The dependency of annual percentage change of ratio of dangerous cargo amount transported by rail and road transport on annual percentage change of the total amount of cargo.

Figure 2 shows that the increase of total amount of cargo by one percent decreases the ratio of dangerous cargo amount transported by rail and road transport approximately by 8.44% (the value of square of correlation coefficient is approximately equal to 0.942 – it is a strong correlation). According to physical meaning, it is easy to understand that the directional coefficient of linear function provided in Fig. 2 is an indicator stating the competitiveness of rail transport in respect of road transport (in such case, when transporting the dangerous cargo). In this case, it is clear that rail transport is highly uncompetitive in respect of road transport. Other issue is the expert survey results by applying AHP research method. The expert assessment the results of which are used for application of AHP methodology in further research has been selected to carry out the qualitative analysis of the issue. The assessment criteria are established after the literature analysis of Lithuanian and foreign authors who examine the competitiveness of rail and other transport types. According to Sivilevičius and Maskeliūnaitė, the main criteria describing the development of entire railway system are related to traffic safety, competitiveness and quality of provided services [11]. The safety is especially important aspect in assessment of dangerous cargo transportation, because of high probability of environmental damage in case of accident. Therefore, one of the examined criteria of competitiveness in the study is the ecological aspects. Other two criteria (costs and delivery time) are not related to the quality of provided services. Thus, four criteria are used for comparison of rail and road transports that are also selected by many authors [10] to assess the competitiveness of transport types when transporting various cargos. These are costs, delivery time, safety and ecological aspects. Six experts whose work is directly related to the transport of dangerous goods by road and rail, as well as experts who are familiar with this topic in the area of science have been interviewed to carry out the study. The result of expert assessment shows that the level of competitiveness of rail transport is 81.64%, road transport – 18.36%.

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5 Conclusions 1. After having used the expert assessment and multi-criteria AHP methods, it was established that the rail transport is approximately 80% more competitive in transporting the dangerous cargo. 2. Statistical data analysis shows that if the total amount of transported cargo increases by one percent, the ratio of dangerous cargo amount transported by rail and road transport decreases approximately by 8.44%. It means the rail transport is extremely uncompetitive in terms of road transport. 3. Since the expert assessment result essentially contradicts the results of statistical data analysis, there are grounds to assert that the examination of the competitiveness of the types of transport in the market of dangerous cargo cannot be based on the results of expert evaluation. Acknowledgment. This research was funded by a grant (No. S-LU-18-12) from the Research Council of Lithuania. This research project “EFFECT-RAIL” was performed in cooperation with the Volodymyr Dahl East Ukrainian National University, Ukraine.

References 1. Batarlienė, N.: Risk analysis and assessment for transportation of dangerous freight. Transport 23(2), 98–103 (2008) 2. Bernatavičius, A.: Investigation of rail transport competitiveness in transportation of dangerous and oversized cargo. Master’s thesis work. VGTU, 63 p. (2018) 3. Gelumbickas, G., Vaičiūnas, G.: Analysis of passenger rolling stock faults and its statistics in Lithuania. Transport 26(3), 315–319 (2011). ISSN 1648-4142 4. Juršėnas, V., Vaičiūnas, G.: A survey of methods used for assessing the performance of Diesel locomotives. Transport 22(1), 28–30 (2007). ISSN 1648-4142 5. Kleiva, E.: Research on the specifics of large and heavy goods transport. Transport Engineering and Management, 15th collection of articles by Lithuanian Young Scientists Conference “Science - The Future of Lithuania”, Vilnius, Lithuania, 4th May 2012, pp. 169– 172 (2012) 6. Maskeliūnaitė, L., Sivilevičius, H.: Expert evaluation of criteria describing the quality of travelling by international passenger train: technological, economic and safety perspectives. Technol. Econ. Dev. Econ. 18(3), 544–566 (2012). ISSN 2029-4913 7. Mikulėnas, M., Vaičiūnas, G.: Research on the competitiveness of freight rail transport. Transport engineering and management. A collection of articles from the 15th Lithuanian Young Scientists Conference “Science - The Future of Lithuania”, Vilnius, Lithuania, 4 May 2012, pp. 334–337 (2012) 8. Myamlin, S., Ten, A., Neduzha, L., Shvets, A.: Spatial vibration of cargo cars in computer modelling with the account of their inertia properties. In: 15th International conference on Mechanika 2010: Proceedings of the 15th International Conference. Mechanika Kaunas University of Technology, pp. 325–328 (2010) 9. Motiejūnaitė, D., Batarlienė, N.: Ensuring the requirements for the transport of dangerous goods by road in Lithuania. Transport Engineering and Management, 15th collection of articles by Lithuanian Young Scientists Conference “Science - The Future of Lithuania”, Vilnius, Lithuania, 4 May 2012, pp. 242–246 (2012)

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10. Petraška, A.: Research on the problem of heavy and oversized road transport. Science is the future of Lithuania. Transportation, pp. 504–508 (2007) 11. Sivilevičius, H., Maskeliūnaitė, L.: The numerical example for evaluating the criteria describing the quality of the trip by international train. E&M Econ. Manag. (2), 73–86 (2014) 12. Vaičiūnas, G., Lingaitis, L.P.: Investigating the dynamics of passenger rolling stock deterioration. Transport 23(1), 51–54 (2008). ISSN 1648-4142

Applying the Business Model Canvas to Increase Enterprise Competitiveness: A Case Study of Transport Company Virgilija Vasilienė-Vasiliauskienė1(&), Aidas Vasilis Vasiliauskas2, Monika Donculaitė1, and Ieva Meidutė-Kavaliauskienė2 1

Vilnius Gediminas Technical University, Plytinės str. 27, 10105 Vilnius, Lithuania [email protected], [email protected] 2 General Jonas Žemaitis Military Academy of Lithuania, Šilo str. 5, 10332 Vilnius, Lithuania {aidas.vasilisvasiliauskas,ieva.meidute}@lka.lt

Abstract. The increase of business competitiveness in today’s market is associated with businesses addressing client demands and their ability to create a value that is anticipated by consumer. Thus, a great attention should be paid to business system, as well as maintaining the relationships between balanced business elements. To obtain this goal, it is necessary to use the structure of the business model and to anticipate all the links and its interaction pertaining to value creation and proposition. The aim of this paper is to present the competitiveness improvement strategy and to show that deployment of the Business Canvas Model enables to accurately identify realistic business situation and its weaknesses. A detailed analysis of the company’s activities and external environment is carried out and the data is presented according to the structure of the chosen model. A case study under analysis shows tangible application possibilities, limitations, as well as threats of using the Business Canvas Model that may have effects on maintaining competitiveness. The methods of thematic synthesis and scientific literature analysis, as well as business modelling in accordance with the structure of the Business Model Canvas were applied. The obtained result – a new business activity model. Keywords: Competitiveness Business Model Canvas


Competitive advantage
Business model


1 Introduction In recent decades, a particular attention has been paid to enterprise competitiveness and measures to increase it [1]. There is a widespread discussion about ever increasing competition and companies’ ability (or not) to compete in domestic and foreign markets. According to [2, 3], companies’ competitiveness pertains to rapid and adequate reaction toward market changes and the ability to react before changes will become a reality. Thus, considering that changes in the markets are intense, and active management and © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 158–170, 2020. https://doi.org/10.1007/978-3-030-38666-5_17

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quick response are required to remain competitive, only the selection of the right business model for a specific company or group of companies can ensure the competitiveness [4, 5]. The definition of the “business model” itself is relatively new and understood as a modern business organization approach that helps to achieve a competitive advantage by applying the appropriate organizational principles, and ensuring the efficiency of the company’s performance management [6, 7]. Transport business is of no exception, as it also faces the demands of competitive advantage. Companies in transport sector often solve such matters as continuous improvement of business competitiveness, as well as measures to be taken to obtain this goal. In view of this, this article aims to show that there are certain business management models that can actually contribute to solving the problems mentioned above. To serve this purpose, the Business Model Canvas and its practical applications in a company providing transport services are discussed and analysed. Therefore, the purpose of this article is to provide solutions to increase the competitiveness of a transport company applying the Business Model Canvas. The rest of this paper is organized as follows. The second part of the article provides the concepts on business model, competitiveness of business performance and influential factors. The third part of the article is dedicated to the analysis of the transport company and the applicability of the Business Model Canvas on a specific company, using auxiliary analytical tools, such as competitive environment, consumer demands and macro environment analysis. The fourth part of the article presents the proposed solutions for increasing competitiveness and a project for its implementation. Section five offers conclusions and suggests paths for future research.

2 The Concept of Company’s Competitiveness and Influential Factors. Building Competitive Advantage As previously mentioned, competitiveness in companies and preconditions for its development are one of the most relevant topics in modern business. Its relevance is determined by the growing competition between companies, industries or even countries. Table 1 presents several concepts for competitiveness. The definitions presented show that competitiveness is understood as company’s ability to respond and adapt to market changes [8–12]. Moreover, in his definitions on competitiveness, [13] presented the structure i.e. competitive potential, competitive advantage and competitive position. Author claims that competitiveness is in fact a result of multiplying these factors and distinguished structural elements of competitiveness show the advantage of one economic unit against another or how these elements are lagging from one another. In assessing the elements, the advantage or backwardness is determined considering different points in time as adequately selected factors constitute a good start in a competition process. A good competitive position means a place won in a competitive battle throughout the whole strategy implementation period. Thus, competitive advantage can be regarded as a link between a competitive potential and competitive position.

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Author Navickas and Malakauskaitė [8]

Beniušienė and Svirskienė [9] Keršienė [10] Clucow [11]

Simanavičienė et al. [12]

Concepts of competitiveness Competitiveness expresses a relative positioning of a company, branch of industry, region, country or a group of countries (economic, social, technological, etc.) in respect to other companies, branches of industry, regions, countries or a group of countries Competitiveness is a complex category rather than a situation or state. It is an intricate concept defining the ability of an object or entity to compete in terms of time, location and conditions Competitiveness is linked to operational efficiency and the extent of economic value to be created largely depend on it In a global market, company’s competitiveness is associated with its ability to respond rapidly to changing market conditions and maintain its position in it In a broad sense, competitiveness is defined as the ability to produce goods and services that meet the needs of international markets, as well as ensures and enhances actual citizen’s income. In the narrow sense, only separate foreign trade and macroeconomic indicators are used to define competitiveness

Adomaitis [14] suggests dividing the factors of competitiveness into the following two groups: external and internal. External environmental factors form opportunities and constraints, while internal activities are directly related to company’s operations. On the basis of the Factor Analysis, companies have opportunities to prioritize it and identify the possible impact of these factors on overall results, in this case – competitiveness, since accurate identification of factors and response measures constitute efficient competitiveness in the market. According to [6] and [15], the primary focus should be technologies and innovations, however, [14] suggests taking a broader and deeper look into this process, i.e. he claims that determining or limiting reasons should also be taken into account. Company’s activities should be assessed in a comprehensive manner, i.e. financial, human resources, internal processes and client perspectives – all must be well considered. And it is necessary to do that gradually: at first, the simplest performance improvement solutions that do not require high investments or additional competencies, are implemented; further on, more complex and substantial changes to company’s activities are taken. [16, 17] claim that creation of competitive advantages, maximum satisfaction of consumer demands, and timely adaptation to changing conditions have the greatest impact on enterprise competitiveness. Table 2 provides researchers’ attitudes and approaches to competitive advantage.

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Table 2. The approaches to competitive advantage (compiled by authors). Heading level Hakkak and Ghodsi [16] Korsakienė [17]

Liučvaitienė and Peleckis [18]

Christensen [19]

Example Competitive advantage is defined as a reason for which revenues increase over expenses Competitive advantage determines the ways in which managers should assess their competitive position and implement adequate actions Competitive advantage is a very broad concept comprising comparative and absolute advantages. Absolute advantage is defined as the ability to deliver products to the market at lower costs. The interaction between absolute and comparative advantages can ensure the competitive advantage, which means that it is not sufficient to manufacture cheap products nowadays, rather, there are other important factors, such as product quality, its variety and placing it on the market prior competitors do. This constitutes the comparative-competitive advantage Competitive advantage is any form of value created by business that motivates clients (or end-users) to purchase this product or service instead of purchasing it from competitors. This value prevents other potential competitors from emerging

Definitions presented in Table 2 indicates that researchers emphasize value and advantage over competitors [17–19]. To sum up the aforementioned opinions, it is possible to claim that competitive advantage is the ability to create effective value that exceeds the value created by competitors and increases profitability in the long run. This advantage over competitors is acquired when the company can offer the highest value possible to the consumer. One of the measures in creating and increasing competitive advantage is the use of business model in company’s activities.

3 Applying the Business Model Canvas to Build Competitiveness Every company strives to gain a competitive edge and therefore relies on several assumptions and calculations in its operations, and no matter what the activities of the company are, it must always have a business model, albeit not clearly defined. Hence, the activities of every company can be analysed on a basis of a particular business model. According to [20–22] all companies directly or indirectly apply business models that determine value creation design and architecture at the same time indicating mechanism for activities to be improved. [6] states that the essence of business models is to define the ways in which a company presents value created, encourages consumers to pay for that value, and turns it all into profit. The company needs to know the preferences of its clients and how to meet these demands in the best way possible. Business model reflects company’s business logic and shows what is offered to clients and how to reach and further on maintain relationships with clients and partners and earn money.

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According to [23] business model is something that connects strategy and its implementation, it is the essence of business concept that is later on transferred into practice. In other words, strategy is a plan according to which business model is adapted. It is possible to claim that business models support companies in executing activities successfully, maintaining competitiveness and gaining competitive advantage. It should be noted that acting according to certain business model alone is not enough, as it is important to constantly observe market and adjust business model based on timely changes taking place. A business model is considered as tool (a method or a logic) that describes a company’s ways of achieving profit by evaluating and describing different segments of business model. To assess business model through value creation, it is possible to rely on business model definition proposed by [24] in which two components are distinguished – valuerelated activities and sales-related activities. Value creation covers such elements as design, production and supply. In terms of obtaining value, (i.e., activities pertaining to sales), consumers (its segmentation and identification), sales, transactions, presentation and delivery can be distinguished as separate elements in a business model. [25] highlight that applicability of business models is understood as a method to experiment and test the business hypothesis for creating and capturing value. Better decisions can be made if there is an understanding on how the entire business system works. In this article, the analysis of the company’s activities is based on the Business Model Canvas, which was designed to help displaying business elements schematically and turning them easy and comfortable to model. Model developers, Fritscher and Pigneur [25] define the Business Model Canvas as a visual tool for analysing company’s activities and creating value for consumer. Authors claim that this model is not aimed at generating processes, however, it shows company’s performance on the map and provides an overview of the current environment for its participants. The Business Model Canvas can be used at different stages of company’s life and as a reference point whilst implementing the most appropriate solution. Typically, the following positive features of the Business Model Canvas are distinguished: • visual representation of the model structure and interconnection between structural elements; • model is easily developed and altered under changing environment, as well as simply adaptable to newly-established goals; • everything it takes to start a work is a new Business Model Canvas drawn on any suitable surface; • structural elements can be grouped or even replaced during the creation process; • this model is useful for seeing the perspective, determining close links between structural elements and establishing components that are lacking in company’s activities. [7] define the Business Model Canvas as an open business model, aiming at capturing innovative strategies that improve the performance of the firm and the use of this model helps to better plan and identify the sources of value creation and the links with business strategy. The application of this model enables to simultaneously explore market and changes in product or service developments. According to [25], the main idea behind the Business Model Canvas is to create a dynamic business tool that has a

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certain flexibility and easily adapts to changing market conditions. Structural parts of this model: customer segments, value propositions, channels, customer relationships, revenue streams, key resources, key activities, key partners and costs. Thus, the application of the Business Model Canvas will enable to determine company’s problem areas and increase competitiveness after eliminating it. In order to properly analyse company’s activities and to create a Business Model Canvas, additional information is required, which can be obtained from company’s performance analysis. Table 3 presents performance logic of transport companies and stages enabling to determine problem areas. Table 3. Logic and stages of business performance analysis in transport company (compiled by authors). Stages

Analysis

External and internal environment analysis for drawing Business Model Canvas

• • • • • • • • • •

Drawing Business Model Canvas

Competitive environment analysis

Analysis on consumer demands

Macro-environment analysis

SWOT of a company under analysis

Identifying business performance problem

profitability analysis; partner analysis; cost analysis; analysis on constant consumer change; analysis on revenue streams; analysis on key resources; analysis on key performance positions; analysis on consumer relationships; consumer segmentation the results of the analysis enable gradual implementation of the Business Model Canvas; • the main aim is to determine the present situation of the company under analysis; • potential business problems are forecasted • the main aim is to determine activities carried-out by companies engaged in similar type of business; • Porter’s five forces framework is applied; • comparison of the range of offered services by the company under analysis to services offered by other companies • interview with constant consumers of a company under analysis; • identified are the services they are mostly interested; • potential and prospective consumers are analysed • market analysis from Import/Export perspectives; • the main aim is to determine possibilities of a company under analysis in implementing transportation services • The SWOT analysis is applied to summarize and identify company‘s strengths, weaknesses, opportunities and threats • possible problems and improvement directions in a company are identified; • decisions to increase competitiveness are made

After completing the Business Model Canvas and analysis (see Table 3) in accordance with the aforementioned stages, it is possible to determine the current state

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of a company, its core values and forecast possible issues. The main objective of the competitive environment analysis is to determine what do other companies engaged in a similar type of business offer to their consumers (this will enable to compare the range of services offered by a company under analysis with the services offered by its competitors). At the same time, analysis on consumer demands will help to determine whether services package provided by a company is in line with the needs established by present consumers and if there is a demand for new services. The Macro-environment analysis shows the trends prevailing in the current market and performance possibilities in a company. SWOT analysis enables to determine all weaknesses, strengths, possibilities and threats as well as a problem is identified. After identifying the problem, the directions for improvement will be determined and certain decisions to increase company’s competitiveness will be made.

4 Customizing the Business Model Canvas for Transport Company According to the structural elements of the Business Model Canvas, a comprehensive company’s analysis has been carried-out. Figure 1 presents a developed business model for transport company under analysis (based on the structure of Business Model Canvas). The company’s analysis was carried-out in accordance with the Business Model Canvas which enabled to understand the proposed value to the customer. The proposed value is the major element that affects and drives the entire mechanism in a company. This analysis helped to identify the underlying problem in a company, i.e. the shortage of support given to competitiveness (see Fig. 2). This characteristic is manifested in such factors as the decline in company’s profitability indicators, number of regular customers, and the like.

Fig. 1. Business model of transport company under analysis (based on business model canvas development logic).

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Fig. 2. Identification of performance problems in transport company under analysis (compiled by authors).

Additionally, the following analyses on company performance were carried-out. Competitive Environment Analysis. The competitive environment was analysed in accordance with the Porter’s five forces framework. After completing this analysis (Table 4) it has been noted that transport company is facing a great competition in Lithuanian market. The analysis has shown that a great number (89%) of other companies, i.e. competitors, offer a wider range of services, which leads to a greater advantage over the company under analysis. Also, companies offering a wider range of services are much more attractive to consumers and can make long-term contracts. It is necessary to systematically analyse consumer demands under changing market conditions and eliminate/add certain elements to company’s activities accordingly. Table 4. Competitive environment analysis results of transport company. Threat factor Current competitors Service substitutes Suppliers Buyers Potential competitors

Impact The company under analysis offers a narrow range of services, while most other companies mainly operate in the EU and offer additional services Considering that the researched company operate only in Lithuania and its territory is small in comparison to other European countries, the threat of service substitutes is particularly evident The power of suppliers is minimal, as providers of this service have a tendency to compete and focus on consumer demands The majority of buyers are legal entities At all times, both in the economic upturn and in the downturn, there is a high risk of potential competitors in this area

Analysis on Consumer Demands. To assess possibilities and performance development in a transport company, an expert method is applied to determine services that consumer would be interested in. After completing this analysis, it was determined that

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transport company indeed has a potential consumer who would be interested in company’s services provided in further locations. In this way transport company would establish itself well in a position manufacturer ! consumer as the main obstacle preventing from it is a narrow geography of the service provided. There are a lot of potential consumers, but it is necessary to have an edge over competitors providing similar services to attract them. Macro-Environment Analysis. The Macro-Environment analysis shows that Lithuania is becoming an attractive base for foreign companies which further on enables to assume that the commodity/production exchange will continue, and businesses will expand. Having researched the macro environment, we realise that transportation service is necessary and its provision is expanding to larger markets and this fact manifests in service geographic area development. SWOT Analysis. This analysis (see Table 5) enabled summarizing all of the obtained results. According to data from this analysis, a decision has to be made with regard to such factors as the ways and methods to apply one’s strengths and opportunities, expand service area into the EU, eliminate weaknesses and improve internal environment. Table 5. SWOT analysis of transport company Strengths • Long-term experience; • High quality of service provision in the territory of Lithuania; • Close cooperation with regular consumers and partners Possibilities • Long-term experience; • High quality of service provision in the territory of Lithuania; • Close cooperation with regular consumers and partners

Weaknesses • Narrow geographical territory for provision of transportation services; • A narrow package of additional services; • Permits allow the service to be provided only in the territory of Lithuania Threats • Narrow geographical territory for provision of transportation services; • A narrow package of additional services; • Permits allow the service to be provided only in the territory of Lithuania

Having identified the problem of transport company and carried-out some other additional analyses, the range of company’s services were expanded and supplemented by new services. With the launch of the new transportation and forwarding services within the EU in Lithuania, the company will be able to propose a greater value to consumers. The change of structural elements (colored in green) within business model can be seen in Fig. 3. Here are reflected aspects that increase company’s competitiveness. To discuss each structural element in this model, it can be observed that activities carried out in the company will be supplemented by a new one – freight forwarding. Additionally, the company will be able to offer a wider range of services to its consumer with the added services like transportation services in the EU territory and freight forwarding in Lithuania. It is expected that after adding certain services, a

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company will become more attractive to present and potential consumers, the number of regular consumers will be higher and overall profitability will increase. The company will be able to enhance its competitiveness after the aforementioned indicators are increased.

Fig. 3. Business model for transport company with new services added.

Implementing New Services and Anticipated Benefits. According to present rates and costs, the implementation process of transportation services in the EU territory consists of 3 months and requires an investment of 4,150 Eur. Implementing forwarding services in the territory of Lithuania takes approximately 5 weeks (this includes searching of a new employee, preparing contract template and finding at least 3 new clients). Financial resources are also required – 1,300 Eur. The realistic forecasts, shows that the required investment into implementing transportation service would pay off throughout the first month in the EU territory. The same situation can be detected in an optimistic forecast. Considering the pessimistic forecast, there is a turning point that illustrates that the investment would pay off after 6 weeks. Considering realistic and optimistic forecasts, it is possible to claim that investments are likely to pay off during the first month of a new service execution. However, an investment will pay off only after 4 months should the pessimistic forecast is to be confirmed. The analysis of the Return on Investment has shown that newly installed and implemented services will pay off during the first month with an assumption that regular consumers will execute freight transportation at fixed and previously analysed prices. A decision to expand company’s operations is positive and a company is expected to enhance its competitiveness. Specific results are anticipated after launching new transportation and forwarding services in the EU and Lithuanian territories. Introducing of new services is expected to

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increase company’s competitiveness. The increase of company’s competitiveness is expected to emerge in the form of the following results: • • • • •

Satisfying Demands of Present and Regular Consumers; Increasing the Number of Regular Consumers; Increasing Performance Profitability Indicators; Faster Business Performance Development; Competitive Edge over Competitors.

All of the mentioned measures will benefit company in improving its performance, as well as in expanding its activities. The consumer demands are expected to be satisfied by providing a wider range of services. Thus, the application of the Business Model Canvas enabled to identify the problem and come up with optimal solution methods that did not require huge investments from the company.

5 Conclusions The analysis on the concepts of competitiveness has shown that it can be defined as an ability to manufacture goods or provide services in order to satisfy demands of consumers in a particular market. Both – internal and external factors are important in assessing company’s competitiveness. Company’s activities must be assessed in a comprehensive manner, not only from financial, but also from the perspectives of internal processes, performance and other indicators in order to evaluate reasons that limit company’s competitiveness. A competitive advantage is the ability to create effective value that exceeds the value created by competitors and increases profitability in the long run. The ultimate goal of a company operating in a particular market must be obtaining a competitive edge over its competitors. Having examined the Business Model Canvas as a measure to gain a competitive advantage, it is possible to claim that the use of this model helps to better plan and identify value creation sources and relationships with business strategy. The application of this model simultaneously researches market, services provided or product changes. Upon exploring the activities in a transport company, the Business Model Canvas was applied, as well as the value proposed to consumer and the present situation were determined. The compiling and drawing of company’s Business Model Canvas enabled to identify one major problem in a company – shortage of competitiveness. This problem manifested itself in the decline of profitability indicators, as well as in reduced numbers of consumers and other aspects. Having researched company’s macro-environment in the area of transportation, it was noted that import/export demand is growing within the EU whilst it is reducing toward CIS countries. It was also determined that EU market is attractive for expanding the service area geographically. Having carried-out the competitive environment analysis and expert interview, it was concluded that if company’s competitiveness is declining, the number of regular users and profitability indicators are also in decline. Interviews with regular consumers have shown that their demands and needs are not satisfied due to limited services offered.

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The introduction of new services will provide opportunities to increase company’s competitiveness. There is an anticipation that company’s performance indicators as well as the number of regular consumers will increase and it will have an impact on faster development of company’s activities.

References 1. Chikán, A.: National and firm competitiveness: a general research model. Compet. Rev. Int. Bus. J. 18(1/2), 20–28 (2008) 2. Schaltegger, S., Lüdeke-Freund, F., Hansen, E.G.: Business cases for sustainability: the role of business model innovation for corporate sustainability. Int. J. Innov. Sustain. Dev. 6(2), 95–119 (2012) 3. Baker, W., Sinkula, J.: The complementary effects of market orientation and entrepreneurial orientation on profitability in small businesses. J. Small Bus. Manag. 47, 443–464 (2009) 4. Casadesus-Masanell, R., Ricart, J.E.: From strategy to business models and onto tactics. Long Range Plan. 43(2–3), 195–215 (2010) 5. Andries, P., Debackere, K.: Business model innovation: propositions on the appropriateness of different learning approaches. Creat. Innov. Manag. 22(4), 337–358 (2013) 6. Teece, D.J.: Business models, business strategy and innovation. Long Range Plan. 43(2–3), 172–194 (2010) 7. Trimi, S., Berbegal-Mirabent, J.: Business model innovation in entrepreneurship. Int. Entrep. Manag. J. 8(4), 449–465 (2012) 8. Navickas, V., Malakauskaitė, A.: Konkurencingumo vertinimo metodologinės problemos ir ribotumas [Methodological problems and limitations of competitiveness]. Bus. Theory Pract. 11(1), 5–11 (2009) 9. Beniušienė, I., Svirskienė, G.: Konkurencingumas: Teorinis aspektas [Competitiveness: theoretical aspect]. Ekonomika ir vadyba: aktualijos ir perspektyvos 4(13), 32–40 (2008) 10. Keršienė, R.: Įmonės konkurencingumas globalizacijos sąlygomis [Competitiveness under circumstances of globalization]. Econ. Bus. 13, 546–550 (2008) 11. Clucow, V.: The resource-based view and value: the customer-based view of the firm. J. Eur. Ind. Train. 31(1), 19–35 (2007) 12. Simanavičienė, T., Šimberova, I., Bruneckienė, J.: Regionų konkurencingumo vertinimo teoriniai aspektai. [Theoretical aspects of regions copetetiveness assessment]. Economics 77, 68–81 (2007) 13. Žitkus, L.: Lietuvos geografinė padėtis Europos Sąjungoje kaip strateginis vystymosi veiksnys. ES ekonominės politikos įtaka Lietuvos ūkio plėtrai [Lithuanian geographical situation in EU as strategic factor for development]. Lith. Annu. Strat. Rev., 113–130 (2009) 14. Adomaitis, S.: Konkurencingumas Lietuvos įmonėse. [Competitiveness in Lithuanian companies]. Accessed 18 Jan 2019 15. Bracey, G.: What is Competitivness? https://www.huffingtonpost.com/gerald-bracey/whatis-competitiveness_b_77532.html?guccounter=1. Accessed 18 Jan 2019 16. Hakkak, M., Ghodsi, M.: Development of a sustainable competitive advantage model based on balanced scorecard. Int. J. Asian Soc. Sci. 5(5), 298–308 (2015) 17. Korsakienė, R.: Konkurencinį pranašumą lemiantys veiksniai ir internacionalizacija: sąsąjų tyrimas [Determinants of competitive advantage and internationalization: investigation of interrelationships]. Bus. Theory Pract. 13(4), 283–291 (2012)

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18. Liučvaitienė, A., Peleckis, K.: Konkurencinio pranašumo formavimas globalioje rinkoje: teorinės prielaidos ir vertinimo galimybės. In: Contemporary Issues in Business, Management and Education, 2011 Proccedings, Technika, Vilnius, pp. 181–194 (2011) 19. Christensen, H.K.: Defining customer value as the driver of competitive advantage. Strat. Lead. 38(5), 21–22 (2010) 20. Zott, C., Amit, R., Massa, L.: The business model: recent developments and future research. J. Manag. 37(4), 1019–1042 (2011) 21. McGrath, R.G.: Business models: a discovery driven approach. Long Range Plan. 43(2–3), 247–261 (2010) 22. Philipson, S.: Radical innovation of a business model: is business modelling a key to understand the essence of doing business? Compet. Rev. 26(2), 132–146 (2016) 23. Kinderis, R.: Verslo modeliai – jų semantinė raiška ir struktūra [Business models - their semantic form and structure]. Ekonomika ir vadyba aktualijos ir perspektyvos 1(25), 17–27 (2012) 24. Magretta, J.: Why business models matter. Harward Bus. Rev. https://hbr.org/2002/05/whybusiness-models-matter#. Accessed 19 Jan 2019 (2002) 25. Osterwalder, A., Pigneur, Y.: Business Model Generation: A Handbook for Visionaries, Game Changers, and Challengers. Wiley, Hoboken (2010)

Comparison of Railway Routes Enabling Freight Transportation from the Eastern Border of Poland to the West Wojciech Kamiński(&)

and Aleksander Sładkowski

Faculty of Transport, Silesian University of Technology, Krasińskiego 8, 40-019 Katowice, Poland {Wojciech.Kaminski,Aleksander.Sladkowski}@polsl.pl

Abstract. This article presents railway routes currently used in freight transportation from the eastern border of Poland to western countries. Due to increasing number of transported containers, new alternative routes have been proposed. Then was made a comparison of these routes to determine if the parameters of the proposed routes do not differ significantly from the parameters currently used routes. In order to comprehensively compare the parameters, coefficients have been introduced allowing them to be combined with each other. Parameters that have been included among others the length of route, the number of tracks and the cost of access to the infrastructure. Subsequently calculation the average value of all parameters allow to evaluate the particular route and compare it with the others. Keywords: Railway transport


Railway lines
Freight transport

1 Introduction Due to the large volume of imported goods from Southeast Asian countries in recent years, there is an increase of freight transport in containers mainly from China to Western European countries. Most of the goods are delivered by sea, but some of them are transported by rail through the territory of Poland. A certain threat to the use of rail transport in freight transport from China to Western European countries is the imposition on Russia, through which runs all railways corridors, economic sanctions. In the first quarter of 2014, the turnover between Russia and the countries belonging to the European Union decreased by 3.4% [1]. The use of rail transport reduces transport time from 42–45 days in the case of sea transport, up to 15–17 days by using a train with containers [2]. In 2008, a little over 25 thousand tons of goods were transported in intermodal transport, and in 2013 it was already over 27 thousand tons. Still this transport in Poland is mainly related to the transport of containers to ports in Gdynia and Gdańsk, using mostly by car transport, however, the number of containers transported by rail transport also increases [3]. In 2011 according to the Office of Rail Transport, container transport services were offered by 7 railway carriers, who transported 30% more containers than in the previous year [4]. In 2018 container transports accounted for 97% of the total intermodal transport in Poland and their size was © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 171–184, 2020. https://doi.org/10.1007/978-3-030-38666-5_18

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characterized by an upward trend, because 32.5% more of containers were transported than in the previous year. The vast majority of intermodal transport, as much as 73% was made in international transport [5]. Until the early 1990s, due to political and economic reasons, it was not possible to create a pan-European integrated intermodal rail network. The ongoing process of economic transformation has enabled the transformation of domestic large railway enterprises and the rise of new railway operators on the market, which allowed for the development of international transport [6]. Countries in Asia, such as China, Mongolia, Kazakhstan, have railway infrastructure in different condition, as well as various types of handling terminals, which is a certain difficulty when performing international transport [7]. Another factor to be taken into account in the performance of international transport is the cost of domestic rail transport in China, because production is concentrated mainly in the eastern regions and on the coast. Due to the considerable territorial size of the country, transport to the west, towards the border with Kazakhstan, is time-consuming and expensive [8]. Recently, the trans-Asian railway network has been developing, including railway connection Singapore-Kunming [9]. The international east-west transport corridor is not a single rail route. There is a connection of northern Europe with the Persian Gulf and various variants of routes leading from the east coast of Asia to the countries of Western Europe. The most important of them is the corridor of the Trans-Siberian railway route, then through Belarus, via Poland from Małaszewicze to Kunowice, then to Western Europe or via Ukraine, Slovakia and the Czech Republic to the west [10]. The connection of China via Kazakhstan, Russia, Belarus and Poland to western Europe was presented in 2004 as one of the versions of the Eurasian land bridge. The most involved in these activities were China, because the efficient connection enables problem-free export of goods, which is important for the Chinese economy [11]. Two main railway corridors are used to transport goods between the eastern and western Polish borders, from Małaszewicze to Kunowice and from Medyka to Bielawa Dolna. In connection with the increasing number of containers transported by these routes and the possible gradual overload of currently used container terminals, the possibility of using other terminals and planning new routes to them should be analyzed. The purpose of this article is to present new communication routes that can be used in freight transport from across the eastern Polish border to the west and their comparison with currently used communication routes. The parameters of currently used transport corridors and alternative transport routes will be compared.

2 Container Terminals in Poland Due to the differences between the gauge used in Eastern Europe (1,520 mm) and in Central and Western Europe (1,435 mm) during transport goods from the east (e.g. from China) to Western countries it is necessary to make transshipment or change the wheelbase of wagons. The time required for reloading goods or changing the wheel spacing of wagons together with the document flow process at the border can reach up to 46% of the total time needed to complete the transport order. Changing the wheel spacing of wagons can be implemented by: replacing whole bogies, replacing wheelsets, or using a system of extended wheelsets [12]. The use of the SUW2000 system of

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extended wheelsets, which has been tested in cross-border passenger transport at relatively short distances during freight transport over long distances is difficult [13]. It would be necessary to solve technical problems associated with the carriage of freight wagons over long distances, on different types of rails. Another limitation for this solution is the high cost of the system extended wheelsets, which makes it much cheaper to reload containers at a terminal located on the border or to change the bogies [14]. Wide gauge lines reach the eastern border of Poland, while normal-gauge lines are used for further transport. Container terminals are used for transshipment. Currently are over 20 container terminals in Poland located inside the country. Their number in the last 10 years has increased by 2/3, but they are distributed very unevenly. There are over 10 container terminals located on the Polish borders. They are located at the eastern border of the country with Ukraine and Belarus, at the western border with Germany and in the area of the Gulf of Gdansk serving sea transport [20]. All container terminals present in Poland are shown in the Fig. 1. Most container terminals are located in the vicinity of Warsaw, Poznań, Łódź or Wrocław, while at the same time remaining areas without container terminals, what occurs in Podlasie, Warmia and Mazury and in Kujawy. One of the problems encountered during the construction of new container terminals is the fact that such an investment requires considerable financial outlay. The incurred costs are reimbursed after a long period of time, as a result of which investors choosing to build terminals limit their size to the minimum in relation to the planned use. Later, when there is an increase in transshipments, a terminal that does not have a significant reserve of its use requires expansion, which lasts a certain period of time, making it impossible to significantly increase container transshipment. The consequence of such a situation may be the loss of customers in the case of domestic transport for other types of transport, e.g. car transport, and in the case of international transport (as transporting East to the West) for other transport routes [15]. Due to the limited capacity of container terminals in Poland, railway transport corridors should be run in such a way as to enable the use of existing container terminals to the maximum extent.

3 Main Railway Lines in Poland The map of major railway lines located on the territory of Poland is shown in the Fig. 2. This map shows the permissible speeds on these lines. Different colors correspond to the maximum speeds allowed on railway lines. The maximum speed allowed on the railway network in Poland is 200 km/h, which is reached only by passenger trains. In the case of railway lines with permissible speeds above 120 km/h, such a speed applies only to passenger trains, and freight trains do not exceed 120 km/h [21]. Currently, as the main directions of rail transport development in Poland (2020– 2030), the following were adopted: modernization and revitalization of existing railway lines, modernization of existing ones and building new container terminals, modernization of stations and stops, and undertaking measures to improve the integration of rail transport with road transport [16].

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Standard-Gauge Lines

The largest infrastructure manager on standard-gauge lines in Poland is Polish National Railways (PNR) Polish Railway Lines S.A. The company manages 18,513 km of railway lines, of which approx. 12,000 km (about 60%) is electrified. These lines are in a different technical condition and have different permissible speeds [22]. The percentage structure of maximum timetable speeds in the 2017/2018 train schedule is shown in the Fig. 3.

Fig. 1. Container terminals in Poland [20].

3.2

Broad-Gauge Lines

The longest broad-gauge line in Poland is the Broad-gauge Ironworks Line (BIL) running to Euroterminal in Sławków from the Ukrainian border in Hrubieszów through Zamość, Biłgoraj and Sędziszów. This line has the number 65. The total length of this line is 394 km, it is entirely monorail and non-electrified. The maximum speed is 80 km/h. The train traffic is run by the company PNR, which almost exclusively uses ST44 series locomotives and modernized ST40 version. The company is also the infrastructure manager of this broad-gauge line. The BIL line was built for the purpose of transporting goods, so its route bypasses larger cities and only freight train movements are run there. There are 9 stations on this line: Hrubieszów, Zamość Bortatycze (there is a rolling stock plant here), Szczebrzeszyn, Zwierzyniec Towarowy, Biłgoraj,

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Wola Baranowska, Staszów, Sędziszów, and Sławków. In addition, there are 13 turnouts on the line [21]. The BIL wide-gauge line is a well-functioning, almost independent of the standard-gauge system lines.

Fig. 2. Permissible speed on railway lines in Poland [21].

5.20%

1% 10.40%

200 km/h 160 km/h

24.30%

32.70%

120-160 km/h 26.40%

80 - 120 km/h 40 - 80 km/h less than 40 km/h

Fig. 3. Structure of maximum speeds on railway lines in Poland [22].

Other broad-gauge lines are: line number 217 from the country border in Braniewo to Bogaczewo, open in freight transport from Braniewo to Wielkie Wieżno, line number 205 from the country border in Wielewo to the fuel base in Kotki, line number 57 from the country border in Kuźnica Białostocka to Geniusze use from Kuźnica

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Białostocka to Sokółka, line number 59 from the country border in Siemianówka to Chryzanów, line number 60 from the country border in Terespol to Kobylany, line number 63 from the country border in Dorohusk to the fuel base in Zawadówka, line number 116 from the country border in Werchrata to Kalpisze, use in freight transport from the border to the station Werchrata and line number 92 from the country border in Medyka to Przemyśl Główny, which is the only one of the broad gauge lines in Poland used in passenger traffic [21].

4 Currently Used Communication Routes Different transport corridors are used for freight transport between China and Western Europe. One of them runs along the Trans-Siberian Railway route, the use of which is possible in two different ways: the shortest route from China to Western Europe is the variant running through Kazakhstan, while the most advantageous parameters have a route through Mongolia [17]. This route runs through the territory of Poland. The map of railway lines showing used communication routes on the territory of Poland enabling transportation of goods from east to west is presented in the Fig. 4. Broadgauge railway lines are marked with blue color, standard-gauge lines allowing for freight transportation on the East-West routes with green color, while black color shows normal-gauge railway lines use in passenger and freight transport, and lines open only in freight traffic are marked with red color. 4.1

Use of Standard-Gauge Lines from Małaszewicze to Kunowice

One of the connections used in transport between east and west is the communication route from the terminal in Małaszewicze to Kunowice on the country border using the international railway transport corridor E20. Railway lines located on it are doubletrack and electrified. Freight trains from Małaszewicze goes to Łuków via modernized railway line number 2. The speed limit in freight transport in this section is 120 km/h, both freight and passenger trains run on this line. The section from Łuków to Skierniewice passenger trains passes through Siedlce and Warsaw, however, for freight trains is most often used, the Warsaw Ring Road line number 12 via Pilawa, which is an element of the CE20 transport corridor. This line, except for the short section Piława-Czachówek Wschodni, is deprived of passenger traffic, while the quantity of freight trains on this section is systematically increasing. The speed limit for freight trains in this section is currently 40–80 km/h; there are also numerous speed limits. Currently only are conducted works to maintain the current operating parameters, however, the manager of infrastructure is seeking to modernize this line, which will allow for traveling freight trains a speed 120 km/h in the future. From Skierniewice the continuation of the transport corridor for transit freight trains runs along line number 11 to Łowicz Główny. On this line the permissible speed in freight transport is between 60 and 100 km/h. Both freight and passenger trains run this line. The section from Łowicz Główny to the country border in Kunowice through Kutno, Konin, Swarzędz, the freight beltway by Poznań, Zbąszynek and Rzepin, freight trains runs by railway line number 3. Both passenger and freight trains operate on this line. For freight trains the

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maximum permissible speed is 80–100 km/h. Currently the section of line number 3 between Poznań and Warsaw is undergoing modernization. The section between Września and Konin has been opened for traffic, however, the works are been continued on the section between Konin and Kutno, which means that this section is closed to train traffic. The trains are routed through Toruń Główny and Gniezno. The completion of modernization works is planned for August 2019, and the entire investment will cost 2.6 billion PLN [18].

Fig. 4. Currently used communication corridors on the East-West route [21].

4.2

Use of Standard-Gauge Lines from Medyka to Bielawa Dolna

Another standard-gauge transport route from east to west border of Poland is the use E30 transport corridor. This corridor consists of two-track and electrified railway lines. On these sections, except for the final Węgliniec - Bielawa Dolna, both passenger and freight traffic is carried out. Freight trains from Medyka to Kraków pass by the railway line number 91 through Przeworsk, Rzeszów Główny and Tarnów. The maximum speed in freight transport along the entire length of the line is 120 km/h with the exception of the section Przemyśl Zasanie - Przemyśl Główny, where the speed is 50 km/h. In Krakow freight trains use the freight beltway, then go by line number 133 to Jaworzno Szczakowa. This line, just like the entire railway junction in Krakow, is being modernized. The completion of works is planned for the second half of 2020, and

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the cost of this investment will amount to over 2 billion PLN [18]. Currently the speed limit on this section is from 50 to 100 km/h. After completion of modernization works, the speed for freight trains will be 120 km/h. The line is modernized in stages, and the closures are implemented in a single-track manner, which makes it possible to carry out continuous train traffic on it, however, due to the significant reduction in capacity, freight trains are now routed there mainly at night. From Jaworzno Szczakowa the trains go to Mysłowice, by modernized line number 134, where the speed allowed for freight trains is 120 km/h. Then, getting to Katowice is possible thanks to the fragment of line number 138 from Oświęcim. The maximum speed on this section is 100 km/h. Further part of the route runs along line number 137 to Gliwice. This line is modernized, the maximum speed for freight trains is 120 km/h here. From Gliwice to Opole Główne it is possible to get through Kędzierzyn-Koźle, which requires continuation running the line number 137, and then from there via the line number 136 to Opole Groszowice, where it connects with the line number 132 running towards Wrocław Glowny. These lines have an acceptable speed depending on the section between 50 and 100 km/h. The international transport corridor E30 runs through KędzierzynKoźle. Another option is to run from Gliwice Łabędy to Pyskowice by a line number 135. This line is modernized and the speed allowed there for freight trains is 120 km/h. In Pyskowice is an entry to the line number 132 running through Strzelce Opolskie, Opole Główne, Brzeg, Oława to Wrocław. With the exception of the section Opole Groszowice-Opole Zachodnie, where is a speed limit 70 km/h, the maximum speed for freight trains in this section is 120 km/h. From the Wrocław Brochów station, freight trains use the freight beltway by Wrocław, so that after passing it, go to line number 275 to Miłkowice via Legnica. The speed allowed on this section for freight trains is 120 km/h. In Miłkowice, the freight trains commence driving on line number 282 through Bolesławiec to Węgliniec. Also on this section the speed allowed in freight transport is 120 km/h. From Węgliniec freight trains towards the country border go through modernized railway line number 295 to Bielawa Dolna. In this section, passenger traffic is not carried out, while freight trains run at a maximum speed 120 km/h. The route of the international transport corridor E30 from Węgliniec runs towards the country border in Zgorzelec. However, due to the fact that this line is unelectrified, freight trains are directed mainly towards Bielawa Dolna. Currently works related to the electrification of railway line number 278 from Węgliniec to Zgorzelec have begun. However, until the electrification of the line also on the German side of the border, which is currently not planned, this electrification will not increase the possibility of using this line in freight transport.

5 Alternative Communication Routes Possible to Use There are also other lines, currently unused, in transit transport from east to west of Poland using standard-gauge routes or a broad-gauge BIL route. The map of railway lines with marked (green color) possible to use communication routes on the territory of Poland enabling freight transport from east to west is shown in the Fig. 5.

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179

Use of Broad-Gauge Line BIL and Euroterminal Sławków

An alternative to terminals located directly at the eastern Polish border in Małaszewicze or in Medyka is the possibility of using during reload goods Euroterminal located in Sławków. The terminal has a storage area of 3,500 TEU. On its area are over 24 km standard-gauge tracks and approx. 17.5 km broad-gauge tracks. To this terminal reaches the Broad-gauge Ironworks Line (BIL) runs from the Ukrainian border in Hrubieszów [19]. From the terminal in Sławków, after transshipment or change the wheelbase of wagons, it is possible to continue driving using standard-gauge lines. It is possible to go from Sławków to the Sosnowiec Maczki station and from there by line number 134 to Mysłowice. The further route from Mysłowice towards the border in Bielawa Dolna can be done in the same way as in the case of transport from Medyka described in Sect. 4.2. An additional advantage of use the broad-gauge BIL line may be the fact that there are no passenger trains running on it, which have priority over freight transport and in case of high intensity they may significantly limit the capacity of routes.

Fig. 5. Communication routes possible to use on the east-west route [21].

5.2

Use of Standard-Gauge Lines from Chryzanów to Kunowice

Another terminal that can be used as an alternative to Medyka or Małaszewicze for transit transport through Poland is the one located at the eastern border in Chryzanów near Narewka. Freight train from Narewka go by railway line number 131 to Siedlce. This line is unelectrified, which forces the locomotive change at the Siedlce station or service the entire section with diesel traction. The line from Narewka through

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Hajnówka to Czeremcha is single-track, on the further stretch through Siematycze and Mordy, it is double-track. With the exception of the Narewka-Hajnówka section, where only freight traffic is carried out, passenger trains run on this line. The speed limit on this line is from 80 to 120 km/h. Freight train from Siedlce go to Mińsk Mazowiecki by the electrified, double-track line number 2. The maximum speed in freight transport on this line is 120 km/h. From Mińsk Mazowiecki train should go through the single-track line number 13 to Pilawa. The permitted speed here is 60–100 km/h. In Pilawa, the freight train can enter line number 12 to Skierniewice and continue ride to the border in Kunowice, similarly as in the case drive from Małaszewicze. 5.3

Use of Standard-Gauge Lines from Kuźnica Białostocka to Kunowice

There is also the option of using a logistics center for transshipment in Łosośna near Kuźnica Białostocka. Both broad and standard-gauge tracks reach this center. Transshipment goods such as coal and wood are carried out in this center it mainly for the needs of the nearest region. The center can also be used to reload containers transported from the east to Western Europe. After transshipment to standard-gauge wagons from Kuźnica Białostocka, the freight train may go by line number 6 to Tłuszcz. This line is electrified, on the section from Kuźnica Białostocka to Białystok it is single-track, on the further section it has two tracks. The permissible speed on the section Kuźnica Białostocka-Sokółka is 80 km/h, on the Sokółka - Białystok section it is 100 km/h. The further part of the route after modernization within the framework of the Rail Baltica project will have the speed limit for freight trains 120 km/h. From Tłuszcz freight train should go by line number 13 to Pilawa. It is an electrified line, single-track, the permissible speed almost its entire length is 60 km/h. Further the freight train can go to Kunowice similarly as in the case drive from Małaszewicze.

6 Comparison of Various Communication Routes The list of selected parameters of individual railway routes is presented in the Table 1. Comparison the length of communication routes is presented in Table 2. For its implementation, the length of the currently used communication route from Małaszewicze to Kunowice was assumed, due to the fact that it is part of the transport corridor from China via Mongolia to Western European countries and due to the fact that it is shorter than the route from Medyka to Bielawa Dolna. This comparison shows that there are significant differences in the length of railway communication routes. Another factor that has been analyzed is the cost of access to infrastructure on a studied route. This cost is affected by the length of the route and the category of railway lines through which communication routes run. The gross train weight 2,600 tonnes was assumed for the cost analysis. For the route from Hrubieszów to Bielawa Dolna using the Broad-gauge Ironworks Line (BIL), the cost of access to the infrastructure was not presented due to the fact that this line is managed by PNR BIL, which is both the infrastructure manager and the carrier.

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Table 1. Parameters of the analyzed railway communication routes. Route

Length, km

Traction power network

Number of tracks

Maximum speed, km

Minimum speed, km

Małaszewicze Kunowice Medyka Bielawa Dolna Hrubieszów Bielawa Dolna

650

on the whole route on the whole route except Hrubieszów Sławków except Chryzanów Siedlce on the whole route

2

120

40

2

120

50

1 – section to Sławków; 2 – the rest of the route

120

40

1 – section to Czeremcha and between Minsk and Pilawa; 2 – the rest of the route; 1 – section to Białystok and between Tłuszcz and Pilawa; 2 – the rest of the route;

120

40

120

40

667 753

Chryzanów Kunowice

723

Kuźnica Białostocka Kunowice

760

Table 2. Comparison of the length of analyzed railway communication routes. Route

Lenght, km

Małaszewicze - Kunowice Medyka - Bielawa Dolna Hrubieszów - Bielawa Dolna Chryzanów - Kunowice Kuźnica Białostocka - Kunowice

650 667 753 723 760

Difference with the current variant (in %): – 2.62% 15.85% 11.23% 16.92%

This company presents summary rates for freight transport, but it does not determinate the cost of access to the infrastructure itself. The cost comparison is presented in Table 3. Similarly like in case of routes length to compare the costs of access to the infrastructure, the access price is compared to the currently used communication route from Małaszewicze to Kunowice, because it is the most used and is part of the transport corridor from China through Mongolia to European countries west. This comparison shows that the price differences for access to the infrastructure for communication routes amount to several thousand PLN, and the cheapest way is ride from Medyka to Bielawa Dolna. Table 3. Comparison costs to infrastructure access on the analyzed railway communication routes. Route:

Cost

Małaszewicze - Kunowice Medyka - Bielawa Dolna Hrubieszów - Bielawa Dolna Chryzanów - Kunowice Kuźnica Białostocka - Kunowice

13,315.50 11,723.47 – 14,403.51 15,029.40

Difference with the current variant (in %): PLN PLN PLN PLN

– −11.96% – 8.17% 12.87%

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The aim of a comprehensive comparison of the most important parameters of railway communication routes has been introduced coefficients allowing them to be combined with each other. The parameters taken into account are: – length of the route: were assumed values from 0 to 1. For the route from Małaszewicze to Kunowice, the shortest communication route, the value 1 was assumed, while for the longest route from Kuźnica Białostocka to Kunowice the value 0 was assumed. The proportional intermediate values were assigned to the remaining routes; – traction power network: were assumed value 1 for the route electrified along its entire length, the value 0 for non-electrified routes and the value 0.5 for routes electrified partly, regardless of the length of non-electrified section. This is due to the fact that the non-electrified section forces the exchange locomotives generating additional travel time or handling the whole route with two-traction locomotives; – number of tracks: this parameter takes values from 0 to 1. Its value depends on the length of the double-track section occurring on the whole route, was calculated according to the following formula: Wi ¼

DD ; DC

ð1Þ

where Wi – coefficient including the number of tracks on a route; DD – length of the double-track section (in kilometers); DC – the total length of route (in kilometers). Using this formula double-tracks routes received the value of 1, whereas for singletrack routes the obtained value would be 0. For partially double-tracks routes, values between 0 and 1 were obtained, taking into account the length of single-track and double-tracks sections. – cost of access to the infrastructure: were assumed values from 0 to 1. For the route from Małaszewicze to Bielawa Dolna, the cheapest variant in terms of access to infrastructure, the value 1 was assumed, and for the route from Kuźnica Białostocka to Kunowice for the access to which cost is the highest value was 0 assumed. The other routes received proportional intermediate values. Due to the inability to determine the cost for access to the infrastructure for the route from Hrubieszów to Bielawa Dolna, this parameter was omitted in this case. The comparison of parameters railway communication routes is presented in Table 4 which shows the average value of all analyzed parameters. Due to the lack of data regarding the cost of access to the infrastructure on the broad-gauge route from Hrubieszów to Bielawa Dolna, in the case of this route, the average value concerns only the other three parameters.

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Table 4. Comparison of parameters railway communication routes. Route

Length Traction power network

Number of tracks

Cost of access to the infrastructure

Average value

Małaszewicze Kunowice Medyka - Bielawa Dolna Hrubieszów LHS Bielawa Dolna Chryzanów - Kunowice Kuźnica Białostocka Kunowice

1

1

1

0.52

0.88

0.85 0.06

1 0.5

1 0.46

1 –

0.96 0.34

0.34 0

0.5 1

0.90 0.89

0.19 0

0.48 0.47

The calculated average can take values from 0 to 1.

7 Conclusions Comparison of currently used communication routes enabling freight transport from the eastern border of Poland to western countries with proposed new, alternative routes allows to state that the most advantageous parameters have currently used routes from Medyka to Bielawa Dolna (0.96) and from Małaszewicze to Kunowice (0.88). The second route obtained a slightly worse average value of all parameters due to the fact that it consists of a large number of kilometers of main lines for which the cost of access to the infrastructure are high. The proposed three new communication routes are characterized by similar parameters (0.34–0.48), however noticeable worse than the routes currently used. The definitely lower average value of all parameters proposed new routes is related to the fact that they are longer, so the cost of access to the infrastructure belonging to PNR Polish Railway Lines is higher, because more kilometers must be paid. Moreover, not all new routes are double-track and electrified along their entire length. However, due to the continuous growth number of containers transported by rail through the territory of Poland on the East-West route and the capacity limitations currently used both routes and transshipment terminals in the future it may be necessary to propose new routes. Therefore, the proposed new alternative routes despite the worse parameters may be used allowing the increase of the freight transported by Poland.

References 1. Sładkowski, A., Cieśla, M.: Influence of a potential railway line connecting the caspian sea with the black sea on the development of Eurasian trade. Nase More 4(62), 264–271 (2015) 2. Sładkowski, A.: Prospects for the development of rail transport in the East-West connection. Mechanika Czasopismo Techniczne 14(109), 261–268 (2012). (in Polish) 3. Gajewska, T., Szkoda, M.: Analysis of intermodal transport in Poland. Logistyka 3, 1355– 1364 (2015). (in Polish) 4. Romanow, P., Frąś, J., Koliński, A.: Container transport in Poland in logistic supply chain. Res. Logist. Prod. 1(5), 43–51 (2015)

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5. Nader, M., Kostrzewski, A., Kostrzewski, M.: Technological conditions of intermodal transshipment terminals in Poland. Arch. Transp. 1(41), 73–88 (2017) 6. Rodrigue, J.-P., Notteboom, T.: Dry ports in European and North American intermodal rail systems: two of a kind? Res. Transp. Bus. Manag. 5, 4–15 (2012) 7. Regmi, M.B., Hanaoka, S.: Assessment of intermodal transport corridors: cases from NorthEast and Central Asia. Res. Transp. Bus. Manag. 5, 27–37 (2012) 8. Xu, H.: Domestic railroad infrastructure and exports: evidence from the silk route. China Econ. Rev. 41, 129–147 (2016) 9. Hanaoka, S., Regmi, M.B.: Promoting intermodal freight transport through the development of dry ports in Asia: an environmental perspective. IATSS Res. 1(35), 16–23 (2011) 10. Rodemann, H., Templar, S.: The enables and inhibitors of intermodal rail freight between Asia and Europe. J. Rail Transp. Plann. Manag. 3(4), 70–86 (2014) 11. Lin, C.: China’s new silk road to the Mediterranean: the Eurasian land bridge and return of Admiral Zheng He. ISPSW Strategy Ser.: Focus Defense Int. Secur. 165, 1–23 (2011) 12. Szkoda, M.: Assessment of reliability, availability and maintainability of rail gauge change systems. Eksploatacja i Niezawodność – Mainten. Reliab. 3(16), 422–432 (2014) 13. Graff, M.: The SUW2000 system in 1435/1520 mm changeover communication. Technika Transportu Szynowego 1–2, 34–53 (2016). (in Polish) 14. Sładkowski, A.: Problems of railway container transportations between Europe and Asia. Transp. Eng. 32, 18–23 (2019) 15. Kadłubek, M.: Railways in intermodal transport in Poland. Res. Logist. Prod. 3, 203–211 (2011) 16. Jendryczka, V.: Safety system in rail transport in Poland. Autobusy: technika, eksploatacja, systemy transportowe. 6(18), 1692–1694 (2017). (in Polish) 17. Islam, D.Z., Zunder, T.H., Jackson, R., Nesterova, N., Burgess, A.: The potential of alternative rail freight transport corridors between Central Europe and China. Transp. Prob. 4(8), 45–57 (2013) 18. Błaszkiewicz, D., Szabłowska, G.: Impact of projects implemented by PNR Polish railway lines included in the national railway program until 2023 for transport infrastructure in Poland. Autobusy: technika, eksploatacja, systemy transportowe 6(19), 800–803 (2018). (in Polish) 19. Gąska, D., Margielewicz, J.: Development of the Silesian Logistic Centers in Terms of handling improvement in intermodal transport on the east-west routes. In: Sładkowski, A. (eds.) Transport Systems and Delivery of Cargo on East-West Routes. Studies in Systems, Decision and Control, vol. 155, p. 421. Springer, Katowice (2018) 20. Office of Rail Transport Homepage (in Polish). www.utk.gov.pl. Accessed 22 Nov 2018 21. Nationwide railway base Homepage (in Polish). www.bazakolejowa.pl. Accessed 08 Dec 2018 22. PNR Polish Railway Lines Homepage (in Polish). www.plk-sa.pl. Accessed 03 Dec 2018

The Impact of the Bioethanol Fuel on the Exhaust Gas Emission of a Two-Stroke Engine Keio Küüt(&), Risto Ilves, Arne Küüt, and Jüri Olt Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56, Tartu, Estonia [email protected]

Abstract. The production of exhaust gas emissions in combustion engines has been the subject of many studies all over the world, including exhaust gas emissions produced in the combustion of biofuels. The studies have mainly focused on the production of exhaust gas emissions from using various fuel mixtures in various types of engines. The effect of biofuels on the exhaust gas emissions of two-stroke spark-ignition engines has been studied less. The reason for that is the fact that the two-stroke engines in widespread use have no engine lubrication system and the engine is lubricated by lubricant mixed into the fuel. For example, when using bioethanol, the addition of lubricant to the fuel is complicated because fuel oils generally stratify out of bioethanol. The goal of the article was to investigate the effect of bioethanol fuel blends on the exhaust gas emissions on a two-stroke engine. Particularly, the effect of bioethanol fuel blends on the compounds contained in the exhaust gas emissions of a two-stroke engine was studied. The weight shares of the following compounds were studied: CO, CH, NO2, C3H4O, C4H6, HCHO. The test fuels were petrol with the octane number of 95, medical bioethanol 96.3% (water content 3.7%) and low-grade bioethanol (LGBE80, water content 20%). The additives added to the fuels were Addinol MZ408 two-stroke engine oil, hot-pressed rape oil and refined rape oil. The test data indicated that the use of biofuels in two-stroke engines produces higher shares of several toxic compounds (HCHO) than the use of petrol. Keywords: Regulated components
Alkalyte petrol
Low-grade bioethanol 1,3-butadiene
Acrolein
Formaldehyde




1 Introduction The use of biofuels made of lignocellulose material as engine fuels is a growing trend [1–5]. A big advantage over the use of second-generation biofuels is that no raw materials intended for human consumption are used [1, 4, 6, 7]. An additional advantage of biofuels over conventional fuels is the low concentration of hazardous compounds e.g. carbon monoxide in exhaust gas emissions [8–11]. Exhaust emissions of ethanol fuels must be studied more thoroughly because they are more used in transportation sector. The reason to investigate ethanol exhaust emissions on 2-stroke © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 185–192, 2020. https://doi.org/10.1007/978-3-030-38666-5_19

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engines is the production of smaller engine vehicles: mopeds, moped cars etc. Also, hybrid cars can have 2-stroke power engine. Last, but not least in urban landscaping are used tools that mainly have 2-stroke engines. The main problems are the lubricating properties of ethanol fuel in two-stroke engines and the addition of lubrication-improving additives to the fuel. A two-stroke engine normally has no separate lubricating system and lubricant must be applied together with the fuel. Generally, additives can be classified by their properties, for example additives improving the fuel’s frost-resistance (antifreeze agent), detonationresistance (antiknock), oxidation-resistance (antioxidant), etc. [12]. The emission component of an engine’s exhaust gas emissions are normally divided into two groups: regulated and unregulated emission components. Regulated components of exhaust gas emissions are CO, CH and NOx, while the most well-known unregulated components of exhaust gas emissions N2, NO2, C4H6, C3H4O, HCHO, etc. [13, 14]. It is important to study the effect of bioethanol fuels on the exhaust gas emissions of two-stroke engines because the equipment with such engines are used mainly near the person, which is why humans are directly affected by their exhaust gas emissions. Moreover, very few studies have been conducted regarding two-stroke engines. Among some of the studies, the tests of Favre et al. [15] on regulated and unregulated exhaust gas emissions of mopeds with 4-stroke and two-stroke internal combustion engines are worth mentioning. As the tests were performed with only one fuel (petrol 98), vehicles with various fuel systems were used in tests, assessing the differences in the production of exhaust gas emissions resulting from the formation of different mixtures. Mainly, the effect of bioethanol on the exhaust gas emissions of 4-stroke internal combustion engines has been studied. A good overview of the production of exhaust gas emissions from conventional engine fuels in 4-stroke engines is provided by Hendriksen’s report [14] to TNO Automotive. Upon preparing that export, the regulated and unregulated components of exhaust gas in the emissions of passenger cars were measured. The fuels used were petrol, diesel fuel, LPG and CNG. One author also accounted for the sulphur content of the fuels at the time and tried to replicate future fuels through that [14]. Hendriksen measured all regulated components for every fuel, plus additional 15 different aldehyde components, 22 variously shaped aromatic hydrocarbon components, 40 different hydrocarbon components (C1 to C12) and last, small amounts of nitrated polycyclic aromatic hydrocarbons [14]. Additionally, similar tests with biofuels have been conducted nowadays. For example, the regulated and unregulated components of exhaust gas emissions from combusting ethanol fuels in non-vehicle diesel engines have been measured by Merritt et al. [16]. Also, tests on diesel engines with conventional diesel fuel and ethanol fuel mixtures were conducted by Haupt et al. [17]. Two of the best among the chosen fuels in terms of hazardous compounds in exhaust gas emissions were ethanol fuel mixtures. Also, Guarieiro [18] has studied the effect of biofuels on the exhaust gas emissions of vehicles. There is a general trend that upon using biofuels and biofuel mixtures in spark-ignition engines, the most widespread components of exhaust gas emissions (CO, HC and NOx) are reduced. The goal of the article was to investigate the effect of bioethanol on the exhaust gas emissions on a two-stroke engine. Particularly, the effect of bioethanol fuel on the compounds contained in the exhaust gas emissions of a two-stroke engine was studied.

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The weight shares of the following compounds were studied: CO, C4H6, NO2, CH, C3H4O, HCHO. The test fuels were petrol with the octane number of 95, medical bioethanol 96.3% (water content 3.7%) and low-grade bioethanol (LGBE80, water content 20%). The additives added to the fuels were Addinol MZ408 two-stroke engine oil, hot-pressed rape oil and refined rape oil. As a comparison, the test data for alkalyte petrol are provided.

2 Material and Method The tests were performed on an NPEGG780-2 generator with a two-stroke engine with generator max power output 650 W, nominal 500 W. Generator engine power is rated at 1.5 kW 3,000 rpm. For the use of biofuels, the diameter of the engine’s nozzle hole was modified in the carburetor. The test fuels were petrol with the octane number of 95, medical bioethanol 96.3% (water content 3.7%) and low-grade bioethanol (LGBE80, water content 20%). The additives added to the fuels were Addinol MZ408 two-stroke engine oil and refined rapeseed oil. For adding oil to the test fuel, a special device was used where old was sprayed into the ethanol fuel as small droplets, for the reason that water-containing ethanol does not mix with oils and the usual methods of mixing will have the oil stratifying out of the fuel mixture. The method used for mixing is new and it is not discussed in more detail in this paper, in order to retain the patent’s novelty value. The rate of mixing lubricant into the fuel was 2%. This was due to the usage manual of the oil Addinol MZ408. The ratio of adding rape oil was 2%, in order to ensure comparability of the data. The tests used a generator with a two-stroke engine, in order to ensure stable test conditions. During the tests, mainly the engine’s load and the environmental conditions were monitored. The tests were conducted under three different generator loads: PG = 100, 200, 300 W and at the engine’s crankshaft rotation speed of ne = 3,000 rpm. The following parameters were chosen based on tests, which showed stable generator output up to 350 W. An AVL SESAM-FTIR device was used for measuring particles in the exhaust gas emissions, enabling to register 27 different components. In the course of the tests, the components of the engine’s exhaust gas emissions were measured. The shares of the emission components CO, CH, NO2, C3H4O, C4H6, HCHO were analysed. Under each stated generator load, the exhaust gas emissions were measured for 60 s, at 1-s intervals. Measurements were made for 3 times in each test point. Based on the results, average results and measurement deviations were calculated. For the LGBE80 and rape oil mixture, two nozzles were used in the test, one of them corresponding to the ordinary bioethanol fuel’s dimensions and the other adapted for the use of LGBE80 fuel, in order to compensate for the decrease of energy content in the fuel due to the 20% share of water. In the diagrams, the tests with different nozzle openings are marked as: “LGBE80 Rapeseed oil” and “LGBE80 Rapeseed oil, nozzle ch.”.

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3 Results and Discussion For nitrogen dioxide (NO2) (see Fig. 1a) the highest share occurred when using a BE96 and rapeseed oil mixtures. Also, more NO2 emission was produced when using a BE96 Addinol mixture, alkalyte petrol, and petrol, compared with other ethanol fuels. At the highest load (300 W), the NO2 share was the highest when using alkalyte petrol. The lowest NO2 share (*0 ppm) occurred with LGBE80 fuels. The big difference in NO2 content in exhaust gas emission of BE96 with rapeseed oil could be caused by higher combustion temperature. At given results it is not possible to fully declear and it needs additional research.

Fig. 1. The concentration of nitrogen dioxide at different loads (a); the concentration of carbon oxide at different loads (b).

The highest indicators of carbon monoxide (CO) (see Fig. 1b), occurred when using petrol (petrol with Addinol MZ408) and alkalyte petrol. With the petrol and oil mixture at medium loads, the CO indicator was approximately 60% lower than with alkalyte petrol. The lowest CO share in exhaust gas emissions (just 1,000 ppm) occurred with BE96 Addinol oil mixture. CO production shows how unefficient fuel combustion is. Petrolfuel mixtures have heavy fractions, which is why the air-fuel mixture vaporisation and combustion take more time, leaving more CO in exhaust emission. But with higher power output, LGBE80 fuel mixtures have higher CO concentration, because it seems that water decrease combustion temperature. Interesting fact is that all fuel mixtures with rapeseed oil have their CO exhaust emission increasing parallel with power. Bioethanol with Addinol oil has CO content stable on all loads. C3H4O or also acrolein is a compound produced only with biofuel using BE96 and LGBE80 (see Fig. 2a) because it is a rest product of the combustion process of fatty compounds (lubrication oil) for alcohol-based fuels. This compound’s share in exhaust gas emissions is generally very similar, regardless of the lubricant in the fuel mixture and the load, remaining in the range of 5 to 6 ppm. This compound is not produced in any significant amount when using petrol mixtures. The production of acrolein in 4-stroke engines using ethanol fuels must also be researched.

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Fig. 2. The concentration of acrolein at different loads (a); the concentration of 1,3-butadiene at different loads (b).

C4H6 i.e. 1,3-butadiene emission occurs in higher shares when using a petrol and Addinol oil mixtures (see Fig. 2b) but also when using alkalyte petrol. For fuels BE96 and LGBE80, the indicators are near 2 ppm. Based on that, it can be said that when using an engine with alkalyte petrol and with a petrol and oil mixture exhaust gas, the concentration of 1,3-butadiene in air may exceed the permitted norm. The concentration of HCHO, also known as formaldehyde, in BE96 and LGBE80 fuel mixture exhaust gasses is significantly higher than when using alkalyte petrol and petrol mixture. In a BE96 Addinol mixture exhaust gas, it even exceeds 85% in places. Formaldehyde has so much higher exhaust emission production with biofuels, since it is produced by incomplete combustion of alcohols.

Fig. 3. The concentration of formaldehyde at different loads (a); the concentration of hydrocarbons at different loads (b).

The summary share of hydrocarbons (total hydrocarbons, HC) is presented in Fig. 3b. The results indicate that the emissions are the lowest when using petrol and Addinol MZ408 oil mixture. This result differs from the results of some other authors’ work [12, 20]. The emission indicators of carbohydrates for ethanol fuel mixtures are lower than those of Alkalyte petrol, which corresponds to the results of the previous authors.

CO2, ppm

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Alkylate petrol BE96 Addinol MZ408 BE96 Rapseed oil

100

200 Test Load, W

300

LGBE80 Rapseed oil LGBE80 Rapseed oil, nozzle ch. Petrol with Addinol MZ408

Fig. 4. The content of carbon dioxide at different loads.

Figure 4 presents the averaged shares of CO2 in a two-stroke engine’s exhaust gas emissions. It can be said that up to 50% less CO2 is produced both in using bioethanol and in using LGBE fuel mixtures, compared to the usual petrol mixture. Similar results were obtained by Elfasakhany and Ghazikani et al. [19, 20]. The highest difference of CO2 shares occurred at light engine loads (100 W) and the smallest difference occurred at medium engine loads (200 W). Across all results, the lowest CO2 indicator was displayed by a medical bioethanol (BE96 Addinol MZ408) mixture. The high share of carbon dioxide when using petrol is caused by more efficient combustion of petrol compared with ethanol fuels. CO2 content differences between different loads are caused by equivalent of air-fuel mixture ratios. At lower loads with carburetor engines the air-fuel mixture are higher with biofuel mixtures. On higher loads, more fuel is directed into cylinder to compensate the energy loss caused by biofuel mixtures. This is the reason for higher CO2 concentration in exhaust gas emissions of biofuel mixtures. The data presented in this article highlight the problems entailed in the use of bioethanol fuels. The use of bioethanol fuels in two-stroke engines is possible but if the engine is not redesigned then the exhaust gas emissions produced in the combustion of ethanol fuels can be more harmful to human health than the exhaust gas emissions produced in the combustion of crude oil-based fuels, particularly petrol. It is important to note here that the shares of e.g. HCHO and C3H4O are significantly higher than in the use of ordinary fuels. Important to note is that the modification of engine carburetor were made to ensure the correct air-to-fuel ratio in the cylinder at low engine loads. In addition ignition angle may affect the production of exhaust gas components. Given study can be developed further to study the impact of engine adjustment on the exhaust gas emissions.

4 Conclusion This article is one of the initial investigations into the exhaust gas emissions produced when using bioethanol fuels, studying regulated and unregulated exhaust gas emissions. The results are the basis for further research. The results indicate that by using bioethanol fuels, the shares of CO, NOx and C4H6 in the exhaust gas emissions of a two-stroke engine decrease. The share of substances carcinogenic or toxic to human

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health in an engine’s exhaust gas emissions increases significantly in places when using biofuels. Main results based on tests: • Using ethanol fuel mixtures, the CO exhaust emission is 3 times lower than it is for regular fuel mixtures. Only exception is BE96 Addinol MZ408 mixture, which has concentration of CO in exhaust gas is 14 to 19 times lower all over the board than with regular fuel mixtures. On lower loads BE96 fuel mixtures produce around 19 times less CO exhaust emission and LGBE80 fuel mixtures produce up to 7 times less CO exhaust emissions compared to regular fuel mixtures. • Concentration of NO2 in Low-grade Bioethanol fuel mixture (LGBE80) exhaust gasses is *0 ppm. On lower generator loads BE96 rapeseed oil mixture exhaust gas concentration of NO2 is 4 to 8 times higher than with regular fuel mixtures, although at higher loads its concentration gets lower than with regular fuel mixtures. • Acrolein (C3H4O) is only produced in exhaust gas emission of ethanol-based fuel mixtures. Concentration of Acrolein is changing a little on different loads. • 1,3-butadiene in ethanol fuel mixtures exhaust gas emissions is at least 4 times smaller than with regular fuel mixtures. Ethanol fuel mixtures exhaust gas emission of 1,3-butadiene does not change on different loads. Regular fuel mixtures exhaust gas concentration of 1,3-butadiene is lower on higher loads. • Formaldehyde (HCHO) concentration in regular fuel mixtures exhaust gas is around 5 times lower than with ethanol fuel mixtures. It is important here that the use of bioethanol fuels can be more environmentfriendly, but the increased share of toxic compounds may mean a rapid decline of human health. It is thus important to continue studying this field.

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9. Deh Kiani, M.K., Ghobadian, B., Tavakoli, T., Nikbakht, A.M., Najafi, G.: Application of artificial neural networks for the prediction of performance and exhaust emissions in SIe nõgine using ethanol–gasoline blends. Energy 35, 65–69 (2010) 10. Koç, M., Sekmen, Y., Topgul, T., Yucesu, H.S.: The effects of ethanol–unleaded gasoline blends on engine performance and exhaust emissions in a spark-ignition engine. Renew Energy 34, 2101–2106 (2009) 11. Najafi, G., Ghobadian, B., Tavakoli, T., Buttsworth, D.R., Yusaf, T.F., Faizollahnejad, M.: Performance and exhaust emissions of a gasoline engine with ethanol blended gasoline fuels using artificial neural network. Appl. Energy 86, 630–639 (2009) 12. Mokhtar, A., Atan, N., Rahman, N., Khalid, A.: Review of performance and emissions characteristics of bio-additive fuel on SI engine fuelled by biopetrol. In: Applied Mechanics and Materials, vol. 5, pp. 773–774 (2015). ISSN: 104028. www.scientific.net/AMM773774430 13. Khalek, I.A., Blanks, M.G., Merritt, P.M., Zielinska, B.L.: Regulated and unregulated emissions from modern 2010 emissions-compliant heavy-duty on-highway diesel engines. J. Air Waste Manag. Assoc. 65(8), 987–1001 (2015) 14. Hendriksen, P.: Regulated and unregulated exhaust gas components from LD vehicles on Petrol, Diesel, LPG and CNG TNO Automotive, 1993, 93.OR.VM.029/1/PHE/RR, Projectnr 733150002 (1993). https://www.tno.nl/media/6376/report-lpg-cng-1993.pdf 15. Favre, C., May, J., Bosteels, D., Tromayer, J., Neumann, G., Kirchberger, R., Eichlseder, H.: Regulated and Non-regulated Emissions of Selected State-of-the-Art European Mopeds, AECC SIA 2011. Congress, Strassburg (2011) 16. Merritt, P., Ulmet, V., McCormick, R., Mitchell, W., Baumgard, K.: Regulated and Unregulated Exhaust Emissions Comparison for Three Tier II Non-Road Diesel Engines Operating on Ethanol-Diesel Blends. SAE Technical Paper 2005-01-2193 (2005). https:// doi.org/10.4271/2005-01-2193 17. Haupt, D., Nordstroem, F., Niva, M., Bergenudd, L., Hellberg, S.: “Swedish Transport and Communications Research Board”: The determination of regulated and some unregulated exhaust gas components from ethanol blended diesel fuels in comparison with neat diesel and ethanol fuel, Feb 1999, 29 p (1999). ISSN 1401-1271 18. Guarieiro, L.L.N., Guarieiro, A.L.N.: Vehicle emissions: what will change with use of biofuel? In: Fang, Z. (ed.) Biofuels. IntechOpen (2013). https://doi.org/10.5772/52513. https://www.intechopen.com/books/biofuels-economy-environment-and-sustainability/ vehicle-emissions-what-will-change-with-use-of-biofuel19. Elfasakhany, A.: Investigations on the effects of ethanol–methanol–gasoline blends in a spark-ignition engine: performance and emissions analysis. Int. J. Eng. Sci. Technol. 18(4), 713–719 (2015). https://doi.org/10.1016/j.jestch.2015.05.003 20. Ghazikhani, M., Hatami, M., Safari, B., Ganji, D.D.: Experimental investigation of performance improving and emissions reducing in a two stroke SI engine by using ethanol additives. Propul. Power Res. 2(4), 276–283 (2013)

Research of Mathematical Model of Movement of Six-Axle Locomotives with Controllable Wheelsets Installation Serhii Kliuiev1, Dmytro Bobyr2(&), Gediminas Vaičiūnas3, and Stasys Steišūnas3 Department «Logistic Management and Traffic Safety», V. Dahl East-Ukrainian National University, Tsentralnyi Av. 59a, Sievierodonetsk, Ukraine [email protected] 2 Department «Locomotives», Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Lazaryan Str. 2, Dnipro, Ukraine [email protected] Vilnius Gediminas Technical University, Plytinės 27, Vilnius, Lithuania {gediminas.vaiciunas,stasys.steisunas}@vgtu.lt 1

3

Abstract. Research of mathematical model of movement of six-axial locomotive with controllable wheelsets installation. Based on the general system of nonlinear variable coefficient differential equations of the vehicle movement in a rail track with inequalities in plan, the mathematical model of movement dynamics of locomotive of improved design with the axial formula 30-30 as an object of automatic control of the wheelsets position in the rail track is considered. Movement simulation is performed on the example of a six-axle locomotive at the speeds of movement and parameters of the curvilinear track sections, which coincide with the conditions of the experiment presented in the thesis work of V. N. Yazykov. The article presents research results of the mathematical model of movement of the improved locomotive bogie with controllable wheelsets installation in the curvilinear track sections using the Matlab/Simulink software package. The results of experimental studies of the All-Russian Scientific-Research and Design Technological Institute of Rolling Stock and the performed theoretical studies show that the efficiency of the improved system for controlling the wheelset position is higher than that of the serial design, in all modes of movement. The improved system of automatic control of wheelsets position makes it possible to reduce guiding forces by 35%. The possibility of using the mathematical model of locomotive movement of the axial formula 30-30 of improved bogie design with axle-box links of adjustable length, taking into account the dynamics of the automatic control system of the wheelsets installation in the rail track, is theoretically substantiated. The theoretical research found out the reduction of lateral forces in the improved bogie design during the passage of curvilinear track sections. The use of the explored mathematical model of locomotive movement reduces the volume and complexity of research works, as well as increases the reliability of engineering calculations when designing new and improving existing designs of the locomotive underframe. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 193–202, 2020. https://doi.org/10.1007/978-3-030-38666-5_20

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S. Kliuiev et al. Keywords: Mathematical model
Dynamics
Curvilinear track section
Radial installation
Wheelset
Controllable movement
Numerical methods

1 Introduction In modern operating conditions of the existing rolling stock there is a problem of intensive tread reduction of wheelsets, which is related to the force interaction of the wheel and the rail, especially in the curvilinear track sections. Speed increase of the railway rolling stock increases the dynamic component of the forces acting in the wheel-rail system, which leads to unproductive energy consumption for traction and premature wear of the running gear of locomotive and rail track [1]. In this regard, the task is to reduce the force action of the wheel tread on the rail, the wear of wheels and rails, as well as to ensure the movement safety and stability. Theoretical studies and practice of domestic and foreign experience have established that 80% of the causes of tread damage are due to imperfect design of rolling stock and about 20% – for the reasons dependent on the track condition. Dynamic properties of a vehicle in the horizontal plane and side wear of the wheel flange and rail head depend on the wheel climbing angle on the rail, condition of the locomotive underframe, which can be effectively influenced by automatic control of the wheel movement process. Bogies with passive installation of the wheelsets are subjected to increased undulatory movement in the straight track sections and do not allow wheelset to turn in horizontal plane when passing the curvilinear track sections [2–7].

2 Problem Statement In modern operating conditions of the existing rolling stock there is a problem of intensive tread reduction of wheelsets, which is related to the force interaction of the wheel and rail, especially in the curvilinear track sections. This results in the increased costs for repair and maintenance of locomotives and track. Solution of this problem is connected with the creation and research of fundamentally new vehicle designs.

3 Analysis of Research and Publications The promising direction of reducing the force interaction of wheel and rail and, as a consequence, of reducing the intense wear in the wheel-rail system is the application of rational designs of locomotive underframe, completed by a system of active control of the wheelsets’ turning in the horizontal plane when moving in the curvilinear track sections [6, 8–10].

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4 Purpose The article is aimed at theoretical investigation of the dynamic processes occurring in the mechanical part of the improved bogie of the locomotive and the wheel-rail contact when passing the curvilinear track section.

5 Methodology Movement simulation is performed using the example of six-axle locomotive at the speeds of movement and parameters of the curvilinear track sections, which coincide with the conditions of the experiment presented in the thesis work of Yazykov [11].

6 Main Material The modern approach to the development of any technical system with a mechanical part involves performing theoretical studies of its behavior in the conditions close to the real ones. The most commonly used research method at the stage of designing a system or machine is the computer simulation method. The basis of this method is a mathematical model and software tools. The software complex, developed on the basis of the proposed models and algorithms, makes it possible to conduct research of the railway vehicle dynamics when moving in the track of arbitrary profile. The study of dynamic processes of curve negotiation is of significant interest. Using the developed computer model of the six-axle locomotive movement, the calculations on curve negotiation were made. According to the mathematical model, the research of dynamic processes was carried out both during controllable and uncontrollable curve negotiation of the diesel locomotive and the results reliability was assessed. During the tests, a number of parameters were measured, of which the value of the frame and side forces when passing a curved track sections are of interest. Frame forces were determined by the transverse displacements of the box relative to the bogie frames, which were multiplied by the rigidity of the transverse connection of the box with the bogie frame. The rigidity of transverse connection was determined by the calibration. Friction forces of the bearings were excluded. The task of studying the locomotive dynamics in a full spatial position when moving along the curvilinear track sections requires the creation of the complex mathematical model. Necessary mathematical apparatus includes positions of analytical and differential geometry, mathematical analysis, differential equations, numerical methods for solving the systems of differential, differential-algebraic, non-linear, and linear algebraic equations. The mathematical model of the six-axle vehicle movement is considered using the example of the locomotive 2TE116. The underframe of the locomotive 2TE116 axial formula 2(30-30) consists of four three-axle bogies. Each wheelset is with motor. The springing is individual. In the axle box stage of spring suspension, four spring kits and two friction dampers as oscillation

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damper were applied for each axle box. The jawless type of axle box is connected to the bogie frame with the help of axle-box link located skew-symmetrically. The axlebox links are equipped with joints with rubber-metal elements, allowing elastic vertical and transverse displacements of the boxes. During simulation, underframe of the locomotive 2TE116 is represented as a nonlinear mechanical system consisting of solid bodies, connected by joints or elastic elements, with which the oscillation dampers of viscous or dry friction are paralleled. The rail track is considered as two beams lying on a homogeneous elastic base; in the transverse direction the rails are presented as a spring with viscous friction. It is considered that the load, evenly moving along one of the rail beams, does not affect the other and the rail deformation under adjacent wheels; reciprocal displacements of rails and bases, as well as their longitudinal displacements are absent. The track weight is reduced to the wheel in the area of its contact with the rail. By the moment of the flange contact with the side edge of the rail, the transverse component of the friction force in the wheel and rail contact does not cause rail displacement. Such assumptions simplify solution of the problem without significant loss of the calculation accuracy. It is assumed that the position of the mass centers of locomotive elements does not depend on the oscillations of the sprung parts, the load is evenly distributed on the wheels, the profile contour form of all the treads is the same, and the forces of traction or braking are constant at a given movement speed. Elastic and dissipative elements are taken as weightless. When setting the elasticdissipative parameters, the following assumptions were taken: the body pivots are elastically connected with the bogie frames in the longitudinal direction. For the description of the dissipative properties of the rubber body mounts, a linear model of viscous friction was taken. The friction of friction dampers of the axle-box suspension and the traction motors’ noses along the crossbar of the elastic suspension is described by the Coulomb model. When describing the macrogeometry of the rail track, the ratios of differential geometry are used. The random vertical and horizontal inequalities of the rails are imposed on the ideal track geometry. The model of force interactions in the wheel-rail contact is based on the nonlinear theory of the Kalker’s creep. The friction forces at the contact points of the wheel and rail are determined as the forces of dry friction, they are constant when moving in the curvilinear track section. The proposed improved bogie design and the automatic control system (ACS) for the wheelset installation is presented in the works [12, 13]. The system of automatic control of the wheelset position contains the control object, the measuring block, the computing device and the actuating unit. The climbing angle is measured by the method of acoustic emission. The sound intensity is determined by microphones, and the speed of the locomotive by the tachometers installed on the bearing bodies of the traction gearbox. Parameters of the curved track section are determined by the track model based on the data of the GPSreceiver. The functions of the control device include the processing of information coming from the microphones, tachometers and the GPS-receiver, forming a controlling influence of the regulator, which is fed to the actuating unit.

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The controlling influence of the regulator is formed taking into account the undamped centrifugal acceleration of the locomotive movement and the direction of its turning in the track section. The climbing angle is controlled by the actuating unit through the corresponding rod movement. The actuating unit with the help of power cylinders pivotally connects the axes that do not turn with the bogie frame and the body. As a source of energy, it is proposed to use a pneumatic reservoir of the brake system of the locomotive connected to the actuating unit by means of pipelines equipped with adjustable electromagnetic valves. Pneumatic cylinder was selected as the actuating mechanism of this unit. Hydraulic cylinders are installed on the last wheelsets of the bogie. Determination of the climbing angle of the wheel on the rail is performed by processing the acoustic signal arising in the wheel-rail contact, the processing algorithm of which is given in the work [13]. Based on the general system of nonlinear variable coefficient differential equations of the vehicle movement in the track with inequalities in plan, the mathematical model of movement dynamics of locomotive of improved design with the axial formula 30-30 as an object of automatic control of the wheelsets position in the rail track is considered. The mathematical model of the locomotive movement with the axial formula 3030, proposed in the works [8, 14, 15], is taken as the basis. The modes of locomotive movement with constant speed are studied; it is considered the steady movement of a vehicle at constant curvilinearity value and the superelevation of the outer rail: the track has geometric inequalities in the rails in plan, which are set according to the recommended real random disturbances from the rail track [11, 16–18]. According to the Lagrange algorithm of the second kind, the operations of differentiation of the expressions for the kinetic, potential energies and the energy dissipation function of the system are carried out. Given that the solution of the problem in the time domain entails a large amount of calculations when integrating differential equations, the Runge-Kutta integration algorithm of the fourth order with a variable step of integration is used. In the process of modeling to determine the radius of the curvilinear track section, the following dependence was used: 1=R ¼ X=V;

ð1Þ

where R – is the radius of the curvilinear track section; X – is the angular speed of the bogie frame turn; V – is the linear speed of locomotive. Inertial properties of the vehicle with such a system of radial installation of wheelsets (RIWS) do not change, that is, the matrix of inertial coefficients of the model varies according to the determined turning angle of the wheelset. In the basic mathematical model [8] the equations describing the hunting of the wheel-motor blocks are changed: 2 € i þ IijZ u € ij ¼ KAn € þ IijZ u IijZ ¼ u  ðyAij   yij yAij Þuij þ MTij þ Mij pg;

ð2Þ

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where I – are the main central moments of inertia of these masses; i – is the bogie € ij – is number; j – is the wheelset number; z – is the number of the wheel-motor block; u the turning angle of the i-th wheelset of the j-th bogie relative to the body; KAn – is the  rigidity coefficient and damping in the longitudinal direction; yAij  – is the distance from the bogie axle to the oscillation dampers; yij – is the distance from the bogie axle to the wheelset axle; MTij – is the moment of forces in the wheels and rails contact; Mij – is the weight of the wheel-motor block; p – is the vector projection of instantaneous angular velocity; g – is the gravitation acceleration. The functional dependence of the turning angle of the wheelset relative to the bogie, depending on the parameters of the actuating unit, is substituted in the mathematical model of the movement of the improved six-axle railway vehicle. The functional dependence of the turning angle of the wheelset relative to the bogie, according to the ACS installation of the wheelset in the railway track, has the form: d 3 uij d 2 uij duij ¼ a1 dMðtÞ dt þ MðtÞ; dt3 þ a2 dt2 þ a1 dt þ uij q ffiffi 2 2nT1 T T1 T k4 Mı M~n J b ~n c ; n ¼ 2
c ; k5 ¼ k 2 k 3 k 5 ; a2 ¼ k 2 k 3 k 5 ; a1 ¼ k 3 ; T ¼

a3

a3 ¼

;

ð3Þ

where J – is the inertia moment of the wheelset; c, b – are the elastic and dissipative components of the springing; Mi – is the moment of external load; M~n – is the moment of friction when turning the wheelset; M(t) – is the difference between the moment of friction when turning the wheelset and the moment of external load; k2 – is the coefficient of the sensor transmission; k3, k5 – is the coefficient of the regulator transmission; T1 – is the time constant; n – is the constant of spring suspension. The sequence of movement in track sections is as follows: straight track section, incoming transition curve, arc of radius circle, outgoing transition curve, and straight track section. Superelevation in the transition curve varies according to the linear law. The length of the original straight track section was taken equal to 100 m, the length of the transition curves is 75 m, and the length of the curve arc of the constant radius is 300 m. Transverse elasticity of the rail is taken as a constant value. In the second case, the movement in the track with inequalities is considered. Vertical and horizontal inequalities of the track were constructed in accordance with the methodology of simulation of random disturbances in the railway vehicle-track system. As a result of movement simulation of the 2TE116 locomotive’s bogie of the serial production and the improved system in the Matlab/Simulink package, the results are shown in Figs. 1 and 2.

7 Findings The comparison of the values of the frame and lateral forces obtained as a result of calculations and measured during the tests makes it possible to conclude that the presented mathematical model of the mechanical part of the locomotive 2TE116

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provides reliable results. It can be used for further study of dynamic processes during movement in the curvilinear track sections. The results of experimental studies of the All-Russian Scientific-Research and Design Technological Institute of Rolling Stock and the performed theoretical studies show that the efficiency of the improved system for controlling the wheelset position is higher than that of the serial design, in all modes of movement. The improved system of automatic control of wheelsets position makes it possible to reduce guiding forces by 35%.

Fig. 1. Results of movement simulation of locomotive 2TE116 (R = 300 m, V = 90 km/h): (a), (b) – proposed design; (c), (d) – serial design.

Fig. 2. Theoretical values of the hunting angle of the first wheelset of the locomotive during controlled and uncontrolled passage of the curvilinear track section: 1 – during controllable movement; 2 – during uncontrollable movement.

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The results of the tests are confirmed by the calculation data obtained in the theoretical studies of the six-axial locomotive 2TE116. The calculated values of the frame forces in a curve with the radius of 300 m at the speeds of 70 km/h were 56 kN (maximum) and 33 kN (quasistatic), and the horizontal body accelerations – 0.21 g. As one can see from the presented graphs, the use of the improved bogie design of the locomotive and the developed ACS installation of the wheelsets in the rail track makes it possible to reduce simultaneously the guiding force values within 30%, the climbing angle of the wheel in 3.2 times. Reducing the lateral forces increases the locomotive traffic safety in terms of derailment [9, 11]. The climbing angles of the guiding wheelsets decreased to 3.2 times, depending on the curve radius and the mode of locomotive movement. The greatest effect from the developed ACS installation of the wheelsets in the rail track is observed in the curves with radius from 300 m to 600 m, and slightly less – in the curves with radius in the range of 125–200 m and more than 600 m. Also, the lateral forces between the wheels, wheel flanges and rails when passing the curvilinear track sections with radius from 300 to 600 m decreased in 1.3–1.9 times. The wheelset trajectories coincide with the trajectory of the guiding wheelset. Oscillations of the second wheelset lag behind the first about a quarter of the period, the amplitudes of its oscillations are less, and the contact between the flanges and rails is not observed. The frequency of oscillations of the third wheelset is slightly higher than the first, the amplitude is less, the contact between the flanges and rails is also absent. The locomotive body also makes transverse oscillations in plan with a frequency close to the oscillation frequency of the front wheelsets of bogies with the amplitudes within a few millimeters. The movement of such a locomotive in a straight track section with a speed of up to 100 km/h can be considered as stable, as the development of lateral oscillations of its elements is not observed.

8 Originality and Practical Value The possibility of using the mathematical model of locomotive movement with the axial formula 30-30 of the improved bogie design with the links of adjustable length, taking into account the dynamics of the ACS installation of the wheelsets in the rail track was theoretically substantiated. The theoretical research found out the reduction of lateral forces in the improved bogie design during the passage of curvilinear track sections.

9 Conclusions The results of experimental studies of the All-Russian Scientific-Research and Design Technological Institute of Rolling Stock and the performed theoretical studies show that the efficiency of the improved system for controlling the wheelset position is higher than that of the serial design, in all modes of movement. The improved system of automatic control of wheelsets position makes it possible to reduce guiding forces by 35%.

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The developed mathematical model of the movement of improved six-axial locomotive, taking into account the link of adjustable length makes it possible to predict and compare the dynamic and operation indicators with the reference design. As well, it allows determining the prospects of their application in different railway sections and scientifically substantiating the design of devices for controlling the wheelsets’ position in the curvilinear track sections with the confidence coefficient of 0.98.

References 1. Kapitsa, M., Bobyr, D., Desiak, Y.: Determining permissible speed of tilting train in curved track. Science and transport progress. Bull. Dnipropetrovsk Nat. Univ. Railw. Transp. 4(70), 29–40 (2017). https://doi.org/10.15802/stp2017/109537 2. Bodnar, B.Y., Nechaiev, Y.H., Bobyr, D.V.: Teoriia ta konstruktsiia lokomotyviv. Ekipazhna chastyna [Manual]. PP «Lira LTD» Dnipropetrovsk (2009) 3. Klimenko, I., Kalivoda, J., Neduzha, L.: Parameter optimization of the locomotive running gear. In: 2018 Proceedings of 22nd International Scientific Conference Transport Means, pp. 1095–1098 (2018) 4. Koch, M.: Method for curve recognition and axle alignment in rail vehicles. In: Koch, M., Hentschel, F.G., Himmelstein, R. (eds.) Krouzilek Patent US6571178 B61F 5/00 (2003) 5. Kyryl’chuk, O., Kalivoda, J., Neduzha, L.: High speed stability of a railway vehicle equipped with independently rotating wheels. In: 2018 Proceedings of 24th International Conference on Engineering Mechanics, pp. 473–476. (2018). https://doi.org/10.21495/91-8473 6. Klimenko, I., Černiauskaite, L., Neduzha, L., Ochkasov, O.: Mathematical simulation of spatial oscillations of the “underframe-track” system interaction. In: The 12th International Conference on Intelligent Technologies in Logistics and Mechatronics Systems, ITELMS’2018, 26–27 April 2018, Panevėžys. Kaunas University of Technology, Kaunas (2018, preprint) 7. Mei, T.: Practical strategies for controlling railway wheelsets independently rotating wheels. J. Dyn. Syst. Measur. Control 125, 354–360 (2008). T. Mei, R. Goodall 8. Masliev, V.G.: Scientific basis for the selection of design and technological parameters of devices to reduce wear on the tires of locomotive wheels: Ph.D. thesis in Engineering Science, p. 497, Kharkiv (2002). (in Russian) 9. Teplyakov, A.N.: Ways to reduce the intensity of wear of the crests of wheel pairs of locomotives: Ph.D. thesis in Engineering Science, p. 197, Habarovsk (2004). (in Russian) 10. Pollard, M.: Studies of dynamics of vehicles with cross – braced bogies. Veh. Syst. Dyn. 6 (2–3), 213–216 (1977) 11. Yazykov, V.N.: Application of the model of non-Hertz wheel-rail contact for assessing the dynamic qualities of a freight locomotive: Ph.D. thesis in Engineering Science, Bryansk, p. 155 (2004). (in Russian) 12. Kliuiev, S.: Experimental study of the method of locomotive wheel-rail angle of attack control using acoustic emission. East-Eur. J. Progress. Technol. 2/9(82), 69–75 (2018). https://doi.org/10.15587/1729-4061.2018.122131 13. Spiryagin, M., Lee, K.S., Yoo, H.H., Spiryagin, V., Klyuyev, S.: Study on using noise for development of active steering control system of rail vehicle. In: Proceedings of the 23nd National Conference and Exposition on Noise Control Engineering (Noise-Con 2008) (and the Sound Quality Symposium), 28–31 July 2008, Dearborn, Michigan. USA, pp. 499–506. Curran Associates, Inc. (2009)

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14. Andrievsky, S.M., Krylov, V.A.: Wheel off the rail. Bull. VNIIJT 393, 20–41 (1969). (in Russian) 15. Kalnitsky, L.A.: Theoretical studies of horizontal oscillations of a car on 2-axle bogies with radial installation of wheel sets. Bulletin of TsNIITEI MPS 2884/84, pp. 1–8 (1984). (in Russian) 16. Chernyak, A.Y.: Simulation of random disturbances in the “rail carriage-path” system. Bull. SNU 9, 173–177 (2003) 17. Ban, T.: Friction moderating system to reduce wheel/rail interface problems at sharp curves. Railw. Technol. Avalanche 18, 104–105 (2007) 18. Bruni, S.: Control and monitoring for railway vehicle dynamics. Veh. Syst. Dyn. 45, 733– 779 (2007)

Arrangement of the Continuous Welded Rail on the Curved Tracks of Short Radius Volodymyr Tverdomed1(&) , Viktor Tkachenko1 , Svitlana Sapronova1 , Oleksandr Aharkov1 , and Liudmyla Drahiieva2 1

State University of Infrastructure and Technology, Kirilivska street 9/3, Kiev 04080, Ukraine [email protected], [email protected], [email protected], [email protected] 2 Izmail State University of Humanities, Repina street 12, Izmail 68610, Ukraine [email protected]

Abstract. The jointed track design with timber sleepers is conventional for the trunk lines of Ukraine with radius less than 350 m. Such design is not rational. The fact that the big number of the rail joints is the reason why the dynamic forces of interaction in both vertical and horizontal plane are increasing and, consequentially, development of residual deformation on the rail as well. The transient loads are the main reason why the resources of the rail and vehicle structural members work are decreasing. Considering the continuous welded rail design in the curves of short radius, especially the one which is less than 350 m, need engineer estimate. During the work performed some theoretical study on the possibility to arrange the continuous welded rail of temperature-stress type on the ferroconcrete sleepers in the curves of short radius, especially 300–350 m. Provided the results of the calculations of factors of longitudinal and transverse stability of the railway track with taking into consideration the distinctive features of driving the train. Made the respective conclusions concerning the possibility to operate the continuous welded rail of temperature-stress type in the curves of the radius 300–350 m. Keywords: Longitudinal forces Transverse stability


Continuous welded rail
Curved track


1 Introduction The trunk lines of Ukraine contain the sections of the rail, where the radius of the curve is 350 m and less. The mileage of such sections does not exceed 5% of the total lengths of the main and the station tracks. But we can see the heightened wear-out of the rails exactly in these sections, and also of the wage wheels flanges and intensive storage of the residual deformations of the length of the rails. Almost 30% of the rails, which have errors of contact failure origin on the surface of rolling, including side wear of the tops of rails, are located exactly in such curves. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 203–210, 2020. https://doi.org/10.1007/978-3-030-38666-5_21

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The curves of radius 350 m and less are located mostly in the mountainous areas, where interaction of the rail gage and the rolling stock is complicated by availability of significant longitudinal forces, caused by the grades of railroad lines. Taking into consideration that in the curves of radius less than 350 m they use jointed track design on the timber sleepers, transition to continuous welded rail design with ferroconcrete sleepers will allow significantly reduce the interaction forces between the length of the rails and wage wheels flanges [1]. This allows to hope that the resource of the structural members of the upper construction of the rail gage increases, and the supporting pole of the train movement decreases along with expenditures on repair of the rolling stock and the rail gage [2, 3]. Arrangement of the continuous welded rail in the curves of radius less than 350 m requires improvement of the superstructure rail gage construction comparing to e structure used in the curves of big radius. The need to use the other structures of the railroad line is caused by forceful factors [4, 5], which have an influence on transverse and longitudinal stability and strength of the railroad line. In order to design the new structures of the members of the superstructure of the rail gage or improve the existing one need to know the operation characteristics and values of the forces, which will have an influence on the rail gage. Some researchers use numerical methods to solve this problem [6–9], while others use analytical methods [10].

2 Methods and Course of the Study The railroad line is under dynamic loads from the wheel of the rolling stock, and also of the atmosphere, climate and operation factors. In the curve sections of the rail gage the additional forceful factors occur the value of which depends on the radius of the curve. As the radius of the rail gage section decreases, so the side, frame and directing forces increase and the longitudinal stability of rail and sleeper lattice gate deteriorates [11, 12]. The additional transverse force from the compression effect in the train during braking also will influence on the transverse stability of the rail gage. The additional transverse horizontal forces occur during movement of the train by means of refractions and compressions on tangent and curved sections of the rail gage. The reasons these forces occur are associated with distinctive features of design equipment of the draw bars, namely with availability of eccentricity of packing up of the coupler socket in horizontal and vertical plane. During quasistatic compression of the train his rings are trying to twist during movement. They are held in the main position by their lateral rods of bogies with buffer springs and wage wheels. As quasistatic compression of the train increases, so do twists, causing increase of the longitudinal horizontal and vertical group effect of the wage wheels on the rail gage. Upon that the wheels of contiguous bogies have a different effect on different lengths of the rail, trying to unclamp the rail gage or remove it by the contiguous bogies into the opposite sides.

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The transverse stability of the continuous welded rail in the curved sections depends on the design of the superstructure of the rail gage, is state, value of the force interaction relationship in vertical and horizontal planes and resistance of the rail and sleeper lattice concerning transverse shear [13, 14]. Resistance of the rail and sleeper lattice of the transverse shear depends on characteristics and state of the surfaces of under rail poles, degree of compaction and type of ballast, the way the loads are transferred to the poles. Stability of the rail and sleeper lattice will be provided in the case when the highest possible frame force, transmitted from the wage wheels on the rails, will not exceed the ultimate shearing resistance of the rail and sleeper lattice in the transverse direction [15]. The force interaction of the vehicle and the rail gage in horizontal plane during movement in the curved sections of the rail gage depends on the diagram of guiding of vehicle in curve [16]. During dynamic guiding should distinguish three absolutely different diagrams of guiding of vehicles in curve: free one, twisted one and chord one. These three diagrams correspond to three different diagrams of force interaction. The values of the horizontal transverse forces, which effect on the rail gage, can be determined from consideration of every specific diagram of guiding. Upon that their meaning in all the cases depends on position of the turning center, on value of vertical axial loading and coefficient of friction in the contacts of the wheels with rails. The transverse component of this force also depends on quasistatic force, which refracts the train, the curve radius, distance between the axes of automatic coupling of the vehicles. It is oriented into the middle of the curve during effect of refraction forces. The less radius of the curve and the less distance between automatic coupler sockets, the bigger additional group side interaction of the wage wheels on the rail gage will be, conditioned by quasistatic refraction force in the train. During quasistatic compression of the train in tangent tracks the additional side forces in the wage wheels and rails occur through twists of the train cars according to “herringbone” diagram. An important detail – consideration of the side interaction forces of the wage wheels and the rail gage is important during calculations of stability of the rail gage in the curves. The worst conditions during calculations of transverse stability of the rail and sleeper lattice will occur if the train brakes sharply in the curved section of the rail gage due to occurrence of additional group side forces of the wage wheels interaction and the rail gage from compression of the train. These forces effect in the train outside the locomotive and oriented on outside diameter of the curve. The calculations of the transverse stability in horizontal plane of the rail-sleeper lattice against the transverse shear for the curved sections of such radiuses as 250, 300 and 350 m. In calculations, the design of the track with typical KB joints and the nonsupporting structure of the track with elastic fasteners KPP-5-Кwere taken (for bogies 2-axis of truck wagon of the model TSNII-HZ, for bogies 2-axis of passenger wagon of the model 68-7013 without/with taking into consideration the transverse force from braking). Results of calculation of the stability coefficients (see Table 1).

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Radius of the curve, m

KB, density KB, density KPP-5-K, density KPP-5-K, density 2000 1840 2000 items/km 1840 items/km items/km items/km Truck wagon 2-axis bogies of the model TSNII-HZ (without taking into consideration the transverse force from braking) 250 1.69 1.6 1.61 1.58 300 1.86 1.76 1.77 1.74 350 2.09 2.04 2.01 1.96 The freight wagon 2-axis bogies of the model TSNII-HZ (with taking into consideration the transverse force from braking) 250 1.22 1.16 1.17 1.14 300 1.32 1.25 1.26 1.24 350 1.43 1.4 1.38 1.34 The passenger wagon bogies of the model 68-7013 (without taking into consideration the transverse force from braking) 250 1.39 1.27 1.29 1.24 300 1.8 1.65 1.67 1.62 350 2.12 2.03 1.99 1.91 The passenger wagon bogies of the model 68-7013 (with taking into consideration the transverse force from braking) 250 1.2 1.18 1.12 1.1 300 1.38 1.27 1.28 1.24 350 1.55 1.49 1.46 1.4

The temperature-stressed design of the continuous welded rail is the reason why the significant longitudinal temperature forces during change of the rails temperature concerning temperature of fastening. Upon that temperature stress has a principal effect on longitudinal stability of the rail gage. For this reason when use the continuous welded design of the rail gage need to pay particular attention to the conditions of providing its longitudinal stability. It especially concerns the design of the rail fastening junction. When need to provide the longitudinal stability of the superstructure of the rail gage, need to carry out the following conditions [17]: 1. the longitudinal forces which effect the length of the rail must not exceed the sleepers shear resistance forces in the ballast; 2. the longitudinal forces which effect the length of the rail must not exceed the sleepers shear resistance forces in the rail fastenings. In other words, the longitudinal stability of the rail gage will be provided, if the joint longitudinal dislocation of the sleepers and longitudinal sliding of the rail base on supporting poles will not happen.

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The first condition can be provided in case if the elastic longitudinal reaction of each supporting pole will not exceed allowable resistance of dislocation of this supporting pole along the rail gage, in other words need to carry out inequality [17]:  pr 
 W0 pr aver set max pzg þ pbr ;
lsl þ pt
lsl  Kz

ð1Þ

where ppr zg – is running longitudinal force from the elastic bending of the rail, kN/m; paver – is distributed braking force, transmitted from the wheels of the rolling stock on br the length of the rail, kN/m; lsl – is a distance between the axes of the sleepers, (width of the 1st sleeper span) m; pset t – is distributed longitudinal temperature force, which effects on the  rail (at the joint track) or the welded rail (at the continuous welded rail), kN/m; W pr 0 – is the allowable resistance to displacement of the sleeper along the rail gage (classified as part of one length of the rail), kN; jz – is safety factor on longitudinal stability ðK z ¼ 1:15Þ.

3 77%

2 14%

1 9%

a) 3 67%

2 25%

1 8%

b) 2 48%

3 47%

1 5% 1

2

3

c) Fig. 1. Ratio of the forming total longitudinal sliding force during construction of the rail gage with the rail fastenings KPP-5-K: a – during the service braking; b – during emergency braking; c – during regeneration braking; 1 – a force from elastic bend of the rail; 2 – braking force; 3 – temperature force.

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The second condition will be done in case if total longitudinal forces of rail sliding (together with temperature longitudinal forces) do not exceed force resistance to longitudinal displacement, provided by the rail fastenings [17]: X

 pur  2
R0n aver set phijac þ tem ¼ maxðppr ; zg þ pdr Þ þ pt  rfas þ Kz
lbp

ð2Þ

  r where rpur fas ¼ Kz – is allowable sliding resistance of the length of rail, provided by the fastenings (kN/m). lbp – length of welded rails, m; R0n – value of resistance of longitudinal displacement of welded rails in rail joints, kN. On the basis conducted calculations can determine percentage ratio of sliding forces, which form value of the total longitudinal sliding force. In Fig. 1, presented the examples in form of the results, obtained for the case of movement of the truck van of weight 4,500 t at a speed of 60 km/h. As it is seen in Fig. 1, the longitudinal skidding force from the elastic bend of the rail has no significant on formation of value of the total longitudinal force. In percentage ratio it is located within 5–9%.

3 Research Results The longitudinal braking forces mostly effect on formation of the total longitudinal sliding force and depend on mass of the running vehicles and movement speed. The percentage ratio of the braking force and total longitudinal sliding force depends on regime of running the train (Fig. 1). It achieves the highest meaning – 48% – during regeneration braking. The value of the longitudinal braking force during regeneration braking is significantly affected by longitudinal slope of the track. The longitudinal stability of the rail gage is lost during movement of the truck van of weight of 4,500 t at the speed exceeding 60 km/h during regeneration braking on the lope with heavy grade. The temperature forces have the biggest influence on formation of the total longitudinal sliding force value (Fig. 1). The longitudinal temperature force is the rail temperature deviation function concerning fastening temperature and longitudinal rigidity of the rail fastening junction.

4 Conclusions Analysis of technical condition of the railways tracks in the curves of radiuses 350 m and less, confirmed that there is an extreme need in using more reliable designs of the superstructure of the rail gage, especially on heavy traffic sections with excessive gradients in mountainous areas. Can improve reliability of the railways tracks in the curves of short radius by replacing the timber sleepers on ferroconcrete ones simultaneously with arrangement of the continuous welded rail of temperature-stress type.

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Arrangement of the continuous welded rail of temperature-stress type in the curves of short radius should go on simultaneously with improvement of the rail and sleeper lattice longitudinal displacement resistance in ballast layer. When need to lessen forceful effect of the vehicles on the rail gage, need to introduce additional spreading of the rail track, calculated on the basis of guiding the bogies of the vehicles. Based on the conducted theoretical calculations of the transverse stability of the rail gage along with typical fastenings of the design office and elastic fastenings KPP-5-K, can make the following conclusions: – the best indexes of transverse stability of the rail and sleepers lattice are shown by the design of the rail gage on the ferroconcrete sleepers and typical fastenings of the design office. The rail gage with rail fastenings KPP-5-K has the transverse stability of the rail and sleeper lattice less on 8% comparing to the fastenings of the design office; – the transverse stability of the rail and sleeper lattice in the curve of radius of 300 m, at the average decreases on 10%, comparing to the curve of radius of 600 m; – additional effect of the transverse horizontal force, which occurs during severe braking of the train, lowers the transverse stability of the rail gage nearly on 30%. Based on the results of longitudinal stability calculations can make the following conclusions: – the longitudinal stability of the rail track during under-rail design in case if the train weighing 4,500 t moves at a speed of 60 km/h and at different braking regimes has higher stability index bigger on 5% comparing to the fastening type KB. – the value of the sliding resistance of the lengths of the rail during change of density of the sleepers with 2,000 items/km to 1840 items/km lowers in all the types of fastenings on 8–9%.

References 1. Sapronova, S., Tkachenko, V., Fomin, O., Gatchenko, V., Maliuk, S.: Research on the safety factor against derailment of railway vehicles. Eastern Eur. J. Enterp. Technol. 6/7(90), 19–25 (2017). https://doi.org/10.15587/1729-4061.2017.116194 2. Tkachenko, V., Sapronova, S., Kulbovskyi, I., Fomin, O.: Research into resistance to the motion of railroad undercarriages related to directing the wheelsets by a rail track. Eastern Eur. J. Enterp. Technol. 5(89), 65–72 (2017). https://doi.org/10.15587/-4061.2017.109791 3. Mikhailov, E., Semenov, S., Tkachenko, V., Sapronova, S.: Reduction of kinematic resistance to movement of the railway vehicles. In: MATEC Web of Conferences, vol. 235, p. 00033. EDP Sciences (2018). https://doi.org/10.1051/matecconf/201823500033 4. Martínez, I.N.: Analytical model for predicting the buckling load of continuous welded rail tracks. Proc. Inst. Mech. Eng. Part F J. Rail Rapid Transit 229(5), 542–552 (2015) 5. Rakshit, U.: Study on longitudinal forces of a freight train for different types of wagon connectors. IFAC-PapersOnLine 51(1), 283–288 (2018) 6. Pucillo, G.: Thermal buckling and post-buckling behaviour of continuous welded rail track. Veh. Syst. Dyn. 54(12), 1785–1807 (2016) 7. Lim, N.H.: Parametric study on stability of continuous welded rail track – ballast resistance and track irregularity. Int. J. Steel Struct. 8, 171–181 (2008)

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8. An, R.: Analysis of relationship between lateral stability and dynamic characteristic of continuous welded rail track. Appl. Mech. Mater. 488–489, 1027–1030 (2014) 9. Khatibi, F.: Analysis of railway track lateral resistance. Soils Found. 57(4), 587–602 (2017) 10. Gesualdo, A.: A model for the mechanical behaviour of the railway track in the lateral plane. Int. J. Mech. Sci. 146–147, 303–318 (2018) 11. Hasan, N.: Threshold radius of a ballasted CWR curved track: curve classification. J. Transp. Eng. Part A Syst. 143(7), 4017026 (2017) 12. Danilenko, E., Molchanov, V., Danilenko, T.: The variability of elastic stiffness characteristics of the rail threads side bending and torsion depending on the correlation of acting wheel loads Pdyn/Hdyn. Collected Sci. Works Ukr. State Univ. Railway Transp. 179, 66–82 (2018) 13. Ciotlaus, M.: Ballast bed cleaning and recycling – influence on stability of continuously welded rail track. Procedia Manuf. 22, 294–300 (2018) 14. Dong-Ho, C.: Parametric study of thermal stability on continuous welded rail. Int. J. Railway 3(4), 126–133 (2010) 15. Pucillo, G.P.: On the lateral stability of the sleeper-ballast system. Procedia Struct. Integrity 12, 553–560 (2018) 16. Danilenko, E.I., Chernitskyi, R., Yosyfovych, R., Molchanov, V., Olinyk, L., Soroka, O.: The introduction of accelerated and high-speed trains on the railways of Ukraine requires the development and application of new regulatory tolerances on the width of the rail track in the straight lines and curves. Sci. Pract. J. Railway Transp. Ukr. 2, 36–47 (2017) 17. Tverdomed, V., Karpinskyi, S., Soroka, O.: Influence constructional appearance assembly of rail fastening longitudinal stability of long-welded rails. Collected Sci. Works Ukr. State Univ. Railway Transp. 169, 66–82 (2017)

Modeling of Management Strategies for Manufacturing Technological Processes in Metro Power Supply Projects Ivan Kulbovskyi1(&) , Halyna Holub1 , Svitlana Sapronova1 Viktor Tkachenko1 , and Marina Musorina2

,

1

2

State University of Infrastructure and Technology, Kirilivska street 9/3, Kiev 04080, Ukraine {kulbovskiy,golub.galina}@ukr.net, [email protected], [email protected] Danube Institute of National University «Odessa maritime academy», Fanagoriyska street 9, Izmail 68600, Ukraine [email protected]

Abstract. At the present, metro power supply units used the production and technological potential not to its full extent. The main reasons for this situation are the lack of strategies for the effective formation and implementation of management actions aimed at ensuring the necessary level of utilization of the power supply. Appropriate strategies for effective formation and implementation of administrative actions aimed at ensuring the necessary level of utilization of production and technological potential of metro power supply units are considered. On the basis of modern control technologies, a computer system for controlling operating modes of electric networks can be implemented, which ensures increased reliability, energy efficiency and traffic safety. The intellectual system of metro power supply organized this way is a breakthrough assembly of interconnected electric traction networks with computer environment and technologies for its management, consumers, generating capacities and means of protection, united on the basis of modern principles of a single information space, self-regulation, self-renewal, the principle of supporting a united model of primary data, the principle of synchronous information exchange. Carrying out a complex of organizational changes and construction of new process models are planned, along with attraction of new solutions in the field of information technologies, finding new ways and means of informatization, as well as intellectualization of the processes of power supply management [1], implementation of control and reliability forecast, increase of operational efficiency, optimization of power consumption and increase of movement safety and innovations in the field of creation of technological processes automated control system, which requires a qualitatively new level of informatization [2]. Increasing the efficiency of modern information technologies is possible only through research of joint properties of mathematical models, methods, algorithms, management problems, features of modern and advanced network technologies along with architectural features of power supply networks and information management of computer systems.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 211–219, 2020. https://doi.org/10.1007/978-3-030-38666-5_22

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I. Kulbovskyi et al. Keywords: Power supply system
Strategy
Management
Productiontechnological process
Potential
Project
Metro
Computer systems
Automation

1 Introduction Management of production processes of power supply is one of the main tasks of improving the efficiency of using its production and technological potential. From cybernetics point of view production processes can be considered as controlled feedback processes. At the same time the principle of combined management is implemented, which takes into account the management of deviation, perturbation and condition. As proved by researches this approach, provides the most rational use of production and technological potential of power supply. The main task of managing the production processes of power supply is multifaceted, it implements various strategies for the use of its production and technological potential. When implementing organizational and technical measures for effective solution of applied tasks of power supply, it is necessary to use the assessment of the competitiveness of the services of the organization departments. This is done through marketing analysis based on the widespread use of media. Marketing analysis is an integral part of system analysis and includes the commercial activity of a structural unit. Depending on the scale of an organization and its marketing activities, its goal and many other factors, systemic marketing requirements are formed. Marketing activities should ensure: – reliable information on the situation in the market, including its structure and dynamics of demand for power supply services, etc., that is information about the external environment; – the formation of works meeting the market requirements; the necessary influence on consumers and demand, which provide the maximum possible control over the scope of implementation. Marketing analysis involves the formation of requirements for the quality and quantity of electrical work: – formation of strategy, tactics and methods for assessing demand, as well as mechanisms for stimulating the implementation of services; – evaluation of the results of activity of separate structural units and development of ways for their improvement. The main organizational tasks of marketing can be divided into external and internal ones. External tasks include: – study of patterns and trends of changes in the main indicators of production and economic activity and market conditions; – assessment of the impact caused by scientific and technological progress on the results of the power supply, taking into account the actual state and variants of development of its production and technological potential;

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– analysis of demand volumes in the context of individual indicators that characterize it, market segmentation; monitoring of competitors and quality of works carried out by him. Internal tasks include: – research of scope of services and estimation of clients’ level of satisfaction; – analysis of the causes of defects, violations of the normal operation of metro, failures in the operation of devices and electrical equipment; – estimation of volumes of potential orders not implemented by the structural unit; – research of possible profits from new kinds of repair services of power supply; – assessment of investments necessary for solving new problems of improving the efficiency of the production and technological potential of power supply; – assessment of the risk level in relation to the effectiveness of the implementation of tasks and planned organizational and technical measures; – simulation of the logical structure of goals, functions, tasks and methods of their solution to ensure their system connection in the realization under real-life conditions. The main criteria for evaluating marketing can be: – reduction of the cost of performed work; – growth of the nomenclature of orders; – growth in incomes from sales of services, etc.

2 Methods and Course of Research In market conditions, the operation of power supply is heavily dependent on the structure of the power supply service. Accordingly, there is a need for research on demand and the formation of commercial, technical and technological behavior of power supply on this basis, including the formation of pricing policy. Under real-life conditions of the electricity supply units (ESU) operation, the following pricing strategies can be used: – price change is proportional to the excessive demand; – price change is proportional to the excessive supply; – price changes correspond to demand and supply. Stability of prices is that demand for products (Z), services of the company’s electricity is satisfied. Let us consider the main strategies for using the production and technological potential of ESU. Taking into account the peculiarities of the ESU production processes and the level of its production-technological potential utilization, three alternative strategies for using the production and technological potential can be distinguished (see Table 1). Table 1 shows that the strategies for using the production and technological potential of ESU differ by the ratio between the demand for ESU N1ij products and the supply (production and technological potential of PKG) – N2ij and indicators of quality and efficiency of management of ESU production processes (P), which respectively are determined:

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0t 1  R QðtÞ  QðtÞdt B C B0 C qf ¼ 1  B C; t R @ A QðtÞdt

ð1Þ

0

0t 1   Rt  R P1 ðtÞ  P1 ðtÞdt þ P2 ðtÞ  P2 ðtÞdt B C B0 C 0 ef ¼ 1  B C: t t R R @ A P1 ðtÞdt þ P2 ðtÞdt 0

ð2Þ

0

Table 1. Strategies for using the production and technological potential of metro power supply units. Strategy

Designation Supply and demand correlation The value of the criteria Quality Effectiveness N1ij = N2ij qf = 1 ef = 1 1st strategy S1 2nd strategy S2 N1ij < N2ij qf < 1 ef < 1 3rd strategy S3 N1ij > N2ij qf = 1 ef = 1

Improvement of the level of use of ESU production and technological potential in the implementation of the strategies provided in Table 1 can be achieved by solving a set of corresponding tasks. The first strategy – S1 = S1{N1ij = N2ij ^ qf = 1 ^ ef = 1 ^ Zij = ∅} presumes the full utilization of the production and technical potential of the structural units. This strategy is the most rational (optimal) that can take place in the real-life conditions of the ESU functioning. In the implementation of the S1 strategy, all tasks that are part of the system model of the functioning of the ESU are solved in full, which ensures the maximization of quality and efficiency indicators of the structural unit production processes (qf = 1, ef = 1). Due to the fact that the optimization of the processes of managing the ESU production processes and the use of its production-technological potential comes down to creating external and internal conditions that would lead to the implementation of the first strategy S1. The second strategy of the production-technological potential use involves exceeding the supply over the demand S2 = S2 {N1ij < N2ij ^ qf < 1 ^ Zjk = Zjk}, which causes incomplete use of power supply repair production and technological potential and, consequently, decreases quality and efficiency of management (qf < 1, ef < 1). To balance demand and supply, prices for products and ESU services may be reduced according to the previously set recommendations. In addition, in order to ensure the necessary level of use of ESU production and technological potential, it is necessary to solve different sets of tasks by optimizing the technical level of production. The search for effective financial mechanisms, the interaction between ESU and structural units

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that use their services and products, can substantially improve the use of production and technical potential and, as a result, the financial position of the structural unit. The third strategy for the use of production-technological potential involves dissatisfaction with market demand   S3 ¼ S3 N1ij [ N2ij ^ qf ¼ 1 ^ ef ¼ 1 ^ Zjk ¼ Zjk : Excess of demand over supply (N1ij> N2ij) allows for stable operation. However, in order to meet the demand of the task solution reserve: – providing of power supply units with modern technological processes; – optimization of technological processes of repair of power supply devices; – optimization of the use of technological devices and equipment, etc. Effective solution of these and other technical, technological, economic and organizational tasks ensures an increase in the level of use of production and technological potential, and allows demand exceeding the supply (existing ESU production and technological potential). Under real-life conditions, at this stage, this strategy is less common than strategy S2, due to the general decline in production. Thus, choosing the appropriate strategies, you can manage the production processes of the departments of the power supply sector, ensuring the most efficient use of its production and technological potential.

3 Research Results Over the last years automatic performance of the electrical objects and monitoring of their functioning received a new impulse due to wide implementation of the presentday and perspective computer technologies, and also different microprocessor software based controllers. Rapid development of the microprocessor technology and especially technology of centralized information processing laid the foundation to moving towards decentralized control, which provided the opportunity of automatic performance of administrating the geographically distributed objects and this became the foundation for creating computer driven power supply control system, and its automatic performance requires solution of wide range of economic, dispatching, engineering and operation management. Creation of engineering and manufacturing processes methodology, namely as computer data management enterprise systems of research, optimization and management of modes transient engineering processes of power supply is based on the research of distinctive features of ensemble of engineering processes of the perpetual power supply mode, for each of them the appropriate mathematical model is being formed. We can determine the ensemble of models as follows: the mathematical model of formation of primary information of the mode parameters as the unified information synchronized space, the mathematical model of formation of the unified information model of primary information on the prism of reciprocity, the mathematical model of verification, archiving and cryptographic protection of the primary information, the mathematic model of the distributed data processing of the tasks of optimization of

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power supply regimes of advanced intellectual complexity and dimensionality, the mathematic model of multilevel identification of regimes, segments and power supply networks, the mathematical model of intellectual accounting by differential rates, the mathematical models of the regimes monitoring, assessment of the engineering condition and forecast of the residual life [3]. Based on the obtained ensemble of the mathematical models we can form the generalized mathematical model of the functioning regime of the railroad and the powerful rectifier substation electrical objects power supply. The mathematical models, which are describing the appropriate engineering processes of the network regime functioning in collaboration with generalized mathematical model are the foundation for creation of the unified information model of the primary information of the power networks parameters regimes. The generalized mathematical model and the unified information model, which describe the power supply network functioning regime if the foundation for creation the ensemble of the computer oriented algorithms. The main computer-oriented algorithms are the following ones: the algorithms of identification and determination of the places of abnormal modes, algorithms of intellectual processing and determination of engineering condition and forecast of life of the electrical objects, algorithms of research, situation modeling, analysis and optimization of electric energy consumption, algorithms of correcting the errors of formation of the primary information, algorithms of intellectual accounting, perpetual “sliding” monitoring [3]. The obtained algorithms are the foundation for arrangement of architecture of the enterprise information control system for research, analysis and optimization of the power supply modes. In order to arrange the information exchange by the information control system with outdoor environment and implementation of data export/import procedure we can form the unified information exchange protocols [4]. There is a data base structure being constructed to store the primary information, which reflects the regime of the network functioning, arrays of standard, reference, report information, and also the primary data, manual entering and auxiliary data. When we need to automate electronic document workflow and form the outcome data, we should the program set which performs some functions, such as generation of reports for the ministry, electric power market, statistical reporting and technological information to conduct operation of the equipment. We also implement formation of express and complete emergency and commercial information transfer it to all levels of management. The enterprise information control system of research, analysis and optimization of the power supply networks also can be used efficiently enough to conduct situation modeling to make strategic decision on administration and development of the electric power network, and also to form the financial payment documents to arrange reciprocal payment, which is the foundation for production and engineering potential. The functional and information link between the diagnostic procedures of development of the models and using can be presented as a diagram (Fig. 1). This is the basis for the system of intellectual support of decision making in assessment of the electrical equipment [5], and also the perspective planning and timely technical maintenance and repair.

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Data processing subsystems Database on operation of the equipment

Clustering of data on operation of the equipment

Optimization of the fuzzy model parameters

Technical maintenance and repair of systems of designing

The key systems of monitoring the diagnostic parameters

4

4

3

2

1

2

3 Approval of Conclusion * * * the decisions X =(X1 ,…,Xn ) according to according to the task of the actual Y*=(Y1*,…,Yn*) diagnostics condition

Making decisions level

Expert analysis of the features of the work of the equipment

F=(X,Y)

Level of assessment of actual condition of the electrical equipment

1 The parameter synthesis of the diagnostic model

The structure synthesis of the diagnostic model

Level of structure of the diagnostic model of the electric equipment

X=(X1,….,Xn)

Y=(Y1,….,Yn)

Formal understanding of the power supply equipment object

Level of analysis of the researched object

Fig. 1. The model of intellectual support of decision making on equipment diagnostics processing of the subsystem data.

Analysis of the power supply network object (level I) includes research of structure and function distinctive features of the electrical equipment. We need the list of the key parameters, which are the diagnostic sings of the subsystems and components of the electrical equipment, set of the screening methods and list of defect states for each type of the equipment object [6, 7]. The diagnostic assessment of the electrical equipment is determined by the task of classification: X ¼ ðx1 ; x2 ; . . .:; xn Þ ! Y ¼ ðy1 ; y2 ; . . .:; yn Þ

ð3Þ

where Xi ¼ ðx1 ; x2 ; . . .:; xni Þ are the diagnostic parameters of the equipment, aggregated under principle of uniting with its elements and presented as in the hierarchy; Y – variety of classes of the microprocessor devices state and state of electrical equipment, associated with algorithms of effects on the researched object. The diagnostic models conduct the structural synthesis for different types of microprocessor devices and electrical equipment. The expert is supposed to determine: the list of the incoming linguistic variables, which correspond to the chosen controlled classification of parameters; the number of additive components and type of the membership function for each member; set of fussy rules; the parameters of fuzzy algorithms of logical inference (type of the model, implication method and so on). The fuzzy rules are also generated by the expert. They simulate the logic of the experts while they assess the condition of the electrical equipment and form the knowledge base, constructed in a hierarchy way [8, 9]. Therefore we can obtain comprehensive assessment of the overall condition of the electrical equipment, and also assessment of the condition of its models. The fuzzy diagnostic models of the synthesis parameters (level III) are performed in two phases. The first one is about determination of the parameters of the incoming variables by fuzzy terms of the membership function. We use the clustering methods to

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determine the membership function on the basis of the controlled diagnostic parameters of trends formed in the monitoring system. Therefore there is an opportunity to adapt the diagnostic models on function of work of the devices and equipment and to design the membership function automatically. In the second phase we solve the problem of fussy diagnostic optimization of the model parameters using classical or heuristic methods [10]. The variable weight coefficients of the rules of the knowledge base and the criteria of distance between the intended and real outcome of the fuzzy plurals during classification of the weighted depending on availability/unavailability is incorrect [10]. The obtained fuzzy model is used to assess the actual engineering condition Y* depending on monitoring the data about the parameters X* (level III). Recommendations (level IV) for operation, technical maintenance and the repair works are formed based on results of diagnostics and are used by the engineers during planning. We can develop recommendations on some individual elements, including analysis and elimination of the typical defects, and also on the comprehensive assessment of the conditions of the devices and the equipment respectively. Generally it helps to determine the further strategies of functioning of the entire equipment. Therefore, the offered method opens the opportunity of interaction of system monitoring control and diagnostics and planning of the subsystem of the electrical complex on the basis of actual engineering state. At the same time monitoring can be performed from time or in on-line regime. The possibility to create the information environment of electrical housing is a key element of the approach. Its presence allows to generate the data about work of the microprocessor devices and the power supply equipment and use it to improve reliability of diagnostics and efficiency of making decisions, oriented on operational expenditures of optimization.

4 Conclusions Appropriate management strategies are proposed for effective formation and implementation of actions aimed at improving the level of utilization of production and technological potential of subdivisions of the metropolitan electricity supply sector, which allows reducing energy consumption and increasing the technological potential by 2.4%, increasing labor productivity by 16%. The prospective introduction of intellectual technologies, computerization and intellectualization of the fast-moving technological processes of electricity supply and intellectualization of the power supply system are shown. The methodology of production-technological processes as an information-control system of the research of the modes of the power supply system, which is focused on research and management of the metropolitan’s electricity supply, is presented.

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References 1. Stognij, B.S., Kyrychenko, O.V., Butkevych, O.F., Levitskyi, V.G.: Informing and intellectualization of the electrical power: priorities and practical know-how. Proj. Electrodynamics Inst. Nat. Acad. Sci. Ukr. 3(3), 4–18 (2002) 2. Mikhailov, E., Semenov, S., Tkachenko, V., Sapronova, S.: Reduction of kinematic resistance to movement of the railway vehicles. In: MATEC Web of Conferences, vol. 235, p. 00033. EDP Sciences (2018). https://doi.org/10.1051/matecconf/201823500033 3. Stasiuk, A.I.: Mathematical models of computer intellectualization of technologies for synchronous phasor measurements of parameters of electric networks. Cybern. Syst. Anal. 52(5), 825–830 (2016) 4. Stasiuk, A.I.: Method for assessing cybersecurity of distributed computer networks for control of electricity consumption of power supply distances. J. Autom. Inf. Sci. 49(7), 48– 57 (1985) 5. Sytnik, V.F., Karagadova, Je.A.: Mathematical models in planning and managing the enterprise (1985). К. 214 p. 6. Sapronova, S., Tkachenko, V., Fomin, O., Gatchenko, V., Maliuk, S.: Research on the safety factor against derailment of railway vehicles. Eastern Eur. J. Enterp. Technol. 6/7(90), 19–25 (2017). https://doi.org/10.15587/1729-4061.2017.116194 7. Golub, G.M.: Reliability control of failure-free operation of power supply system of railroad and its components by methods of intellectualization and informatization. Metall. Min. Ind. 5, 8–13 (2017) 8. Kulbovskyi, I.I.: Information model of railway transport power supply system computer monitoring data flow. Metall. Min. Ind. 2, 31–36 (2018) 9. Kulbovskyi, I.I.: Investigation of computer-oriented technologies for the optimization of electric supply and energy saving of railway transport. In: Proceedings of the 2nd Annual Conference on Technology Transfer: Fundamental Principles and Innovative Technical Solutions, Tallinn, Estonia, pp. 1–2 (2018) 10. Shtovba, S.D., Pankevich, O.D., Nagorna, A.V.: Analyzing the criteria for fuzzy classifier learning. Autom. Control Comput. Sci. 49(3), 123–132 (2015)

Improving the Dynamics of Bogies of Railway Freight Cars by the Spring Suspension Enhancement Mykola Gorbunov1(&), Serhii Kara2, Olegas Lunys3, and Gediminas Vaičiūnas3 1

2

Department of Railway and Road Transport, Lift and Care Systems, Volodymyr Dahl East Ukrainian National University, Central pr. 59a, Severodonetsk 93400, Ukraine [email protected] Department of Dynamics and Strength, Branch of the PJSC “Ukrzaliznytsia” “Scientific Research and Engineering Institute of the Railway Transport”, I. Fedorova street 39, Kyiv 03038, Ukraine [email protected] 3 Department of Mobile Machinery and Railway Transport, Vilnius Gediminas Technical University, Vilnius, Lithuania {olegas.lunys,gedimimnas.vaiciunas}@vgtu.lt

Abstract. The paper contains main structural disadvantages of 18-100 bogies, namely large unsprung mass, instability of characteristics, low critical velocity, intense wear and others. The experience of domestic and foreign developments, devoted to improving the dynamics and energy efficiency indicators of freight wagon undercarriage, indicates the need for fundamentally new structures or deep modernization of existing bogies. To study the dynamics of freight wagon, the dynamic model in the licensed software complex “UM 6.0” was improved. As the first stage of verification of the model, a simple model of vertical vibration of a wagon with one degree of freedom was calculated. As the second stage of the verification of the computer model of the wagon dynamics, the data of measurements of accelerations of the elements of the wagon during the running dynamic tests performed in an empty and loaded state are used. According to the results of the simulation, the values of the dynamic coefficients of the spring-suspended and unsprung elements of the bogie are obtained. Technical solution and concept of new bogie are developed. Keywords: Bogie


Dynamics
Spring suspension

1 Introduction Increasing the running qualities of freight wagons and reducing their power performance on the track is one of the most pressing problems of rail transport on the 1,520 mm track. The solution of this problem essentially depends on the dynamic characteristics of the wagon’s bogies, which constitute an important component in the modular architecture of the freight wagon [5]. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 220–224, 2020. https://doi.org/10.1007/978-3-030-38666-5_23

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For many decades, the basis of the running parts of freight wagons of 1,520 mm track is an 18-100 bogie model and their counterparts. By constructive execution, this bogie is a deteriorated version of the three-element Barber bogie of the 1928 model. The 18-100 model bogie according to the technical documentation should provide the speed of wagons up to 120 km/h. However, due to a number of fundamental deficiencies, the bogie of this type is not used for the operation of wagons at speeds above 80 km/h. The main structural disadvantages of 18-100 bogies include: – a large unsprung mass, which is almost 90% of the mass of the bogie; – instability and non-compliance of characteristics of spring suspension in the empty and loaded states of the wagon (insufficient damping in empty mode, and excessive – in loaded); – low critical velocity with respect to self-oscillation; – intense wear of the center plate bearing surfaces; – enlarged, in comparison with the Barber bogie, gaps between the axle box and side frames; – insufficient reliability of side frames and bolster beams; – low inter-repair mileage. The experience of domestic and foreign developments, devoted to improving the dynamics and energy efficiency indicators of freight wagon undercarriage, indicates the need for fundamentally new structures or deep modernization of existing bogies. A rational solution to the problem under consideration is seen in two approaches. Namely, for freight wagons intended for the carriage of bulk cargoes, it is advisable to go through the modernization of running parts, whereas wagons for high-speed container and piggyback transportations must be equipped with bogies of fundamentally new constructions. In both cases, the proposed technical solutions should be based on comprehensive studies of the dynamics and strength of wagons, with emphasis on ensuring the guaranteed safety of technical operation [1, 2].

2 Research of Dynamics To study the dynamics of freight wagon, the dynamic model in the licensed software complex “UM 6.0” was improved on the basis of the basic model of the open wagon dynamics, taking into account the design features of open wagons on 18-100 bogie models, with the possibility of variation of dissipative characteristics of all bogie links. The wagon model includes 19 solids: body, 2 bolster beams, 4 side frames, 8 wedges, 4 wheel pairs. For each solid, 6 degrees of freedom are provided, thus the mechanical system has 114 degrees of freedom. When developing a computer model of the dynamics of a freight wagon, the approach of subsystems is used. Application in modeling the approach of subsystems gives the opportunity to form the same type of subsystem once and use them in the model the required number of times. As the first stage of checkup (verification) of the model, a simple model of vertical vibration of a wagon with one degree of freedom was calculated. The results of

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modeling (numerical integration) of the computer (mathematical) model in comparison with the results of the analytical decision of the differential equation of oscillation (1) and the result of solving the problem of determining the proper vibrations of the body wagon (2): m
€z þ b
z_ þ C
z ¼ 0;

ð1Þ

where m – is mass, b – is the coefficient of damping of oscillations, C – is elasticity. rffiffiffiffi C f ¼ 2p ; m

ð2Þ

where f – is the frequency of torsional oscillations. According to the results of the first stage of model verification, the original error value is 1… 3%. As the second stage of the verification of the computer model of the wagon dynamics, the data of measurements of accelerations of the elements of the wagon during the running dynamic tests performed in an empty and loaded state are used. Accelerometers were installed on the four axle boxes of the first bogie, on the left side frame over the first and second wheel pairs and on the bolster beam. As the estimates of the adequacy of the mathematical model, the Tail’s difference coefficient is used e: qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi Pn p 2 e i¼1 ðxi  xi Þ qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ; e ¼ qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi Pn Pn p 2 e 2 i¼1 ðxi Þ þ i¼1 ðxi Þ

ð3Þ

where xpi and xei – predicted and experimental values; n – the number of verifiable values. According to the standard deviations of acceleration of the wagon elements determined by the data of measurements, and those obtained by the computer model of dynamics, the coefficients of the Tail’s difference are calculated. The values obtained do not exceed 0.11, which indicates the permissible differences between calculated and experimental data. According to the results of the spectral analysis of accelerations realized during running dynamic and strength tests and obtained by simulation, the main frequencies of the running gears were determined. The total relative mean deviation of calculated and measured frequencies is 7.47%. Thus, the experimentally obtained frequencies are quite close to the estimated ones. In the directions of the bogie improvement in order to improve the dynamic indicators, the direction for introducing the axle box grade of spring suspension is chosen. The simulation was carried out for speeds of 30, 60 and 90 km/h for a single wagon equipped with bogies 18-100 type (without axle box grade of spring suspension) in the normal technical condition (hereinafter the existing wagon), and for a wagon equipped with bogies 18-100 type with a draft axle box degree – 15 mm and 30 mm (stiffness of the kit of spring suspension of one axle box, respectively, C1 = 1.8 MN/m and 3.6 MN/m).

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According to the results of the simulation, the values of the dynamic coefficients of the spring-suspended (bolster beam) and unsprung (side frame) elements of the bogie are obtained, which are presented in the Table 1. A technical solution is proposed based on the combination of the design of the pedestal tie bar with elastic elements (Fig. 1). According to this decision, bogie contains a bolster beam 1, which is based on the spring kits that include spring elements 2 and friction shock absorbers 3, side frames 4, wheel pairs 5 with axle boxes, on the jaws of the axle knots, the pedestal tie bar 6 with holes are, axles are made in in the form of cassette bearings 7 in the case 8 with traction passing through the openings of the pedestal tie bars 6 and coupled with elastic members 9 (for example, springs), which rests on pedestal tie bars 6.

Table 1. Comparison of dynamics coefficients

18-100 bogie type 18-100 bogie type with an axle box grade of spring suspension (C1 = 1,8 MN/m) 18-100 bogie type with an axle box grade of spring suspension (C1 = 3,6 MN/m) 18-100 bogie type 18-100 bogie type with an axle box grade of spring suspension (C1 = 1,8 MN/m) 18-100 bogie type with an axle box grade of spring suspension (C1 = 3,6 MN/m)

30 km/h 60 km/h Bolster beam 0.31 0.51 0.30 0.49

0.68 0.66

0.29

0.47

0.63

Side frame 0.38 0.58 0.37 0.56

0.76 0.73

0.35

0.70

0.53

Fig. 1. Technical decision of a bogie with an axle box.

90 km/h

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3 Development of Concept To solve the task of creating a new generation of bogie (concept) with fundamentally new dynamics indicators [3, 4], a concept was created based on the following requirements: 1. Use of elastic-dissipative elements instead of separate supporting elements and suspension elements, which allows to reduce mass-dimensional indicators. 2. Use of rolling carriers instead of castings for frame structures, which cannot be elastically dissipative. This allows you to reduce the mass of elements due to the higher values of permissible stresses. 3. Creation of the pre-stressed state of the most loaded elements. This allows to reduce the maximum values of stresses in operation, to bring the structure closer at the maximum load to the equally stressed. Acknowledgment. This research was funded by a grant (No. S-LU-18-12) from the Research Council of Lithuania. This research project “EFFECT-RAIL” was performed in cooperation with the Volodymyr Dahl East Ukrainian National University, Ukraine.

References 1. Gerlici, J., Gorbunov, M., Nozhenko, O., Pistek, V., Kara, S., Lack, T., Kravchenko, K.: About creation of bogie of the freight car. Communications 19(2A), 29–35 (2017) 2. Gorbunov, M., Gerlici, J., Kara, S., Nozhenko, O., Chernyak, G., Kravchenko, K., Lack, T.: New principle schemes of freight cars bogies. Manuf. Technol. 18(2), 233–238 (2018) 3. Fomin, O., Kulbovskiy, I., Sorochinska, E., Sapronova, S., Bambura, O.: Experimental confirmation of the theory of implementation of the coupled design of center girder of the hopper wagons for iron ore pellets. Eastern Eur. J. Enterp. Technol. 5(1), 11–19 (2017) 4. Fomin, O.V., Lovska, A.O., Plakhtii, O.A., Nerubatskyi, V.P.: The influence of implementation of circular pipes in load-bearing structures of bodies of freight cars on their physicomechanical properties. Sci. Bull. Nat. Min. Univ. 6, 89–96 (2017) 5. Myamlin, S., Lingaitis, L.P., Dailydka, S., Vaičiūnas, G., Bogdevičius, M., Bureika, G.: Determination of the dynamic characteristics of freight wagons with various bogie. Transport 30(1), 88–92 (2015)

The Strength Simulation of a Predeformed Design of a Hatch Cover of Open Car Oleksij Fomin1(&), Nikolai Gorbunov2, Alyona Lovska3, and Yuliia Fomina4 1

4

State University of Infrastructure and Technology, Kyrylivska street 9, Kyiv 04071, Ukraine [email protected] 2 Volodymyr Dahl East Ukrainian National University, Central pr. 59a, Severodonetsk 93400, Ukraine [email protected] 3 Ukrainian State University оf Railway Transport, Feuerbach square 7, Kharkiv 61050, Ukraine [email protected] University of Zilina, Univerzitná 8215/1, 01026 Žilina, Slovakia [email protected]

Abstract. To ensure the strength of the hatch cover of a general-purpose open car under operating conditions of the load, it is proposed to sheathe with a smooth sheet, which has a convex configuration and preload. The hatch cover rails are filled with a viscous substance having damping properties. The strength analysis of the improved design of the hatch cover is carried out for the main schemes of its load under operating conditions, as well as additional ones. The maximum equivalent stresses arising in the hatch cover of an improved design under operational load conditions have been determined. It is established that the strength of the hatch cover is ensured. The results of the research can be used in the designing of new-generation cars with improved technical, economic and operational indicators. Keywords: Open car


Hatch cover
Construction load
Strength

1 Introduction Prospects for the development of foreign economic relations between Eurasian states make it necessary to put into operation railway rolling stock, as one of the most important components of the transport industry, with improved technical, economic and environmental indicators. To solve this problem at the stage of the rolling stock designing, it is important to introduce fundamentally new solutions for its features, which will ensure durability for reliable operation under operating load conditions.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 225–234, 2020. https://doi.org/10.1007/978-3-030-38666-5_24

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2 The Analysis of Recent Research Questions on improving the design of the hatch cover of an open car are given in papers [1, 2]. A feature of the proposed design is the change in the profile sheet, which has a stepped configuration in the part of the fastening, which provides support on the inside part of the hatch of the open car body. In these works, the study of the strength of the hatch cover of an open car under operating conditions is not carried out. The features of theoretical and experimental studies on the implementation of joined execution of the back frame of the pellet cars are considered in the work [3]. The obtained results confirm the constructive efficiency of the joined execution of the back frame of the pellet cars during the established fifteen-year service life. The argumentation for extending the service life of open wagons that have exhausted their standard service life is shown in the paper [4]. To determine the dynamic loading of the open wagon body during shunting, a mathematical model has been built. The results of its solution are taken into account when studying the strength of the open car body, taking into account service wears of structural components. The task of determining the strength indicators of the elements of the car body with regard to their previous loading is not set in these works. The results of determining the type and degree of influence of various freight bogies on the strength properties of the bearing systems of the wagons are given in the work [5]. Studies have been conducted in relation to three types of freight car bogies in the speed range 40–120 km/h. The issues of introducing of cars with improved dynamic characteristics on Barbertype bogies are considered in the paper [6]. Motion simulation of the car was carried out in the “Universal mechanism” software. The work does not pay attention to the issue of improving the carrying structure of the open car body. The peculiarities of the creation of a promising concept of a draw gear of railway open cars are given in [7]. Mathematical and computer modeling of the loading of an open cars body during shunting was carried out to substantiate the use of the proposed concept. Measures to improve the carrying structure of the open car body to ensure the reliability of its fastening on the deck of a railway ferry were proposed in [8, 14]. The paper presents the results of the strength analysis of the body, taking into account its fastening relative to the deck for the proposed structural units when moving in waves. However, the task of determining the strength indicators of the hatch cover of an open car is not set in considered works. Features of the development of technology for the modernization of freight cars during periodic repairs are considered in the paper [9]. Within the framework of the project, it is proposed to produce the car body from composite panels, and to paint it with anti-corrosion materials. It should be noted that there is no study of the strength of the hatch cover under operating conditions in these works.

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A description of the new method of passing of a vehicle through a curved section of the track using multifunctional computing software is given in [10]. The question of determining the strength indicators of the construction elements of vehicles are not considered in the work.

3 The Purpose of the Article Definition of features of the strength simulation of the predeformed construction of the hatch cover of a general-purpose open car. To achieve this goal, the following tasks are defined: – determination of the optimum thickness and radius of the sheet of the rail of the hatch cover; – the construction of a three-dimensional model of the hatch cover and the strength analysis under the main operational loads; – the strength analysis of the hatch cover at the additional operational loads.

4 The Main Content of the Article To ensure the strength of the hatch cover of the general-purpose open car under operating loads, it is proposed to make a sheath with a smooth sheet. In order to ensure sufficient strength of the sheath at shock loads, the sheet has a convex configuration, that is preloading, and the hatch cover rails are filled with a viscous substance having damping properties. To determine the optimal thickness and radius of the sheet of the rail of the hatch cover, it was considered as a spherical shell of a certain radius [11]. Then, the Laplace formula for stress calculation will be: req ¼

P
R ; 2t

ð1Þ

where R – radius of the shell, m; P – value of the pressure acting on the shell, MPa; t – thickness of the shell, m. The calculation has been made for the most unfavorable load mode – a drop of a cargo weighing 150 kg from a height of 3,000 mm onto the hatch cover. This operation conditions are characteristic of car body load with a grab bucket and cause the greatest force impact on its bearing structure. To determine the value of the pressure on the spherical segment, we use the formula: P¼

m
g
hD ; V

ð2Þ

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where m – mass of the load falling on the hatch cover on impact, MN; hD – height of the load drop on the hatch cover, m; V – volume of the spherical segment (surface of the hatch cover), m3. The volume of the spherical segment is determined by:   1 V ¼ p
h2 R  h ; 3

ð3Þ

where h – the length of the perpendicular from the center of the base to the intersection with the surface of the sphere, m.   Then, we can write taking into account the allowable stresses req ¼ 220 MPa, on the hatch cover: 



req ¼

m
g
hD p
h2 ðR13hÞ


R

2t

:

ð4Þ

Then, R¼

2p


2 3 3p
h
r
t h2
r
t  m
g


hD

:

ð5Þ

Therefore, the thickness of the sheet of the hatch cover versus its radius response characteristic has been plotted (see Fig. 1). It can be seen from the figure that the thickness of the sheet of the hatch cover has a linear dependence on its radius.

Fig. 1. The thickness of the sheet of the hatch cover versus its radius response characteristic.

In the calculation, the assumption that the shell has a circular base has been taken into account. For the possibility of making such an assumption, the strength of the hatch cover has been calculated. The thickness of the sheet has been assumed to be 2.5 mm. In order to simulate the strength of an improved hatch cover design, a threedimensional model was built in the SolidWorks software (see Fig. 2).

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In a very elementary stage of the study, the calculation was made for the case when a cargo weighing 150 kg falls from a height of 3,000 mm onto the hatch. The calculation was carried out in the CosmosWorks software using the finite elements method [12]. To take into account the preloading of the sheet of the hatch cover, an elastic connection was established between it and the auxiliary plane, which was used to install the elastic elements (see Fig. 3). Elastic elements are preliminarily kept under pressure of 120,000 N/m2. The pressure value is selected on the basis of the condition of ensuring the strength of the hatch under this load condition. The hatch cover was fastened with the hinges, and an impact load reaction was applied to the locking brackets. а)

b)

c)

d)

Fig. 2. The hatch cover of the improved design: (a) the top view; (b) the bottom view; (c) the side view; (d) the front view.

а)

b)

Fig. 3. Related to the strength calculation of the hatch cover: (a) the strength model; (b) the finite element model (bottom view).

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Isoparametric tetrahedras were used as finite elements. The optimal number of mesh elements is determined using the graphic-analytic method. The finite element model of the hatch cover is shown in Fig. 4. In this case, the number of mesh elements was 56,770, nodes – 17,401. The maximum size of the mesh element is 49 mm, the minimum is 9.8 mm, the maximum aspect ratio of the elements is 411.32, the percentage of elements with an aspect ratio of less than three is 70.7, more than ten is 4.2. In this case the maximum equivalent stresses arise in the hinges and are about 220 MPa, the maximum displacements in the construction nodes concentrated in the locking brackets and are about 13 mm, the maximum deformations are 1.91  10−3. That is, at the assumed loading case, the strength of the hatch cover is ensured [13]. The strength calculations of the hatch cover have also been calculated under other load patterns. The calculation results are shown below. The calculations showed that the strength of the improved design of the hatch cover at the applied load scheme is maintained.

а)

b)

Fig. 4. Results of the strength calculation of the hatch cover: (a) stress state; (b) moving in nodes.

The maximum equivalent stresses at the uniformly distributed load of Pe = 69.9 kN action occur in the hinge areas and are about 140 MPa, the maximum displacements in the construction nodes are in the locking brackets and are about 14 mm, the maximum deformations are 1.61  10−3. Under a distributed load of Pe = 50 kN acting in the center of a hatch cover nan area of 25  25 cm maximum equivalent stresses occur in the corners formed by the longitudinal and cross rails, as well as in the middle hinge area and are about 130 MPa. The maximum displacements in the construction nodes concentrate in the locking brackets and are about 10 mm, the maximum deformations amounted to 1.14  10−3. For the strength analysis of the hatch cover under cyclic shock loads, the numerical value of which is 500, the fatigue strength has been calculated. The conducted calculations made it possible to conclude that the strength of the hatch cover is maintained when testing.

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In addition to the basic schemes for loading of the hatch cover, additional ones are taken into account in operation: 1. imitation of the hatch cover opening when discharging cargo – the nonsimultaneous (first on one of the supports) impact of the hatch with the supports of the cross-bearer of the car frame without a torsion bar (excluding work of a torsion bar (-s)) with the maximum opening angle; 2. imitation of the hatch cover opening when unloading cargo – the simultaneous impact of the hatch cover with the supports of the cross-bearer of the car frame without a torsion bar (excluding work of a torsion bar (-s)) with the maximum opening angle; 3. non-simultaneous opening of latch hooks – supporting of the hatch of a loaded car on one latch hook on one bracket (a case when one latch hook is broken, and the other one is still not broken) 4. tightening (closing) of the hatch cover of the unloaded car with a crowbar. The calculation results are shown in a Table 1. Table 1. Results of the strength calculation of the hatch cover. Loading case I II III IV

Maximum equivalent stresses, MPa 183.5 85.9 214.2 6.3

Movement in structural nodes, mm 3.41 0.94 17.9 0.36

Deformations 1.24  10−3 7.06  10−4 2.1  10−3 3.75  10−5

Table 1 shows that the maximum equivalent stresses act on the hatch cover during the III additional loading case. The maximum equivalent stresses in this case occur in the angular hinge of the hatch cover, and the maximum displacements in the structural nodes are in the lock bracket area (see Fig. 5). a)

b)

Fig. 5. The results of the strength calculation of the hatch cover in the case of the nonsimultaneous opening of the latch hooks (a) stress state; (b) moving in nodes.

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The distribution of equivalent stresses along the length of the hatch cover sheet is shown in Fig. 6. Maximum stresses in this case are concentrated in the interaction of the sheet with the cross rail area.

Fig. 6. Distribution of equivalent stresses along the length of the hatch cover sheet.

Fastening of the sheet to the hatch cover rail is done by welding. Calculation has been made to study the strength of the joint weld at the most unfavorable loading pattern of the hatch cover. It was the case when a cargo weighing 150 kg falls from a height of 3,000 mm onto it. In this case, the strength condition has the form [11]: rj ¼

3
M N
2 þ  RrY ; F b
hj
l j

ð6Þ

where M – the bending moment acting in the cross section of the joint; b  hj – the effective throat thickness; b – the weld penetration factor; lj – the effective joint length; N – the calculated force acting on the joint; F – the joint area; RrY – the design joint resistance. Taking into account the calculations, the value rj = 123 MPa is obtained for RrY ¼ 196:1 MPa. That is, the strength condition is fulfilled. The research of statistic data of damages to open cars in operation allows us to conclude that hatch covers are one of the most frequently damageable elements of their bearing structures. To maintain the strength of the manhole cover it has been proposed a fundamentally new design. A special feature of the hatch cover is that the lining is made of a smooth sheet, which has a convex configuration and preload, the hatch cover rail is filled with a viscous substance having damping properties. When designing the hatch covers of general-purpose open cars at car production facilities, the main schemes of their operational loads are taken into account. It is important to note that the regulatory documents to which the hatch covers are designed do not take into account additional schemes of their operational loads: imitation of the hatch cover opening when discharging cargo – the non-simultaneous (first on one of the supports) impact of the hatch with the supports of the cross-bearer of the car frame

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without a torsion bar (excluding work of a torsion bar (-s)) with the maximum opening angle, imitation of the hatch cover opening when unloading cargo –the simultaneous impact of the hatch cover with the supports of the cross-bearer of the car frame without a torsion bar (excluding work of a torsion bar (-s)) with the maximum opening angle, non-simultaneous opening of latch hooks – supporting of the hatch of a loaded car on one latch hook on one bracket (a case when one latch hook is broken, and the other one is still not broken), tightening (closing) of the hatch cover of the unloaded car with a crowbar. Therefore, to ensure the strength of the open car hatch cover, it is proposed to introduce a new design and in addition to the main schemes to take into account the additional load ones at the design stage. The research will facilitate reducing the cars operation and repair cost, as well as improving the efficiency of their operation.

5 Conclusions 1. An improved design of the hatch cover of a general-purpose open car has been developed. In this context, the hatch cover lining is made of a smooth sheet which has a convex configuration and preload and its rail is filled with a viscous substance having damping properties; 2. The strength of the hatch cover at the main and additional operating load conditions has been calculated. Studies have made it possible to conclude that the hatch cover strength under operating load conditions is provided taking into account measures to improve it. The maximum equivalent stresses in the hatch cover occur when a load weighing 150 kg falls onto it from a height of 3,000 mm and is about 220 MPa. That is, they do not exceed the permissible ones; 3. The conducted research will contribute to the creation of a new generation of the railway rolling stock and to increase the efficiency of its operation.

References 1. Kebal, I.Yu., Myamlin, S.V.: Sovershenstvovanie konstruktsii kryishki lyuka poluvagona. Vagonniy Park 7–8, 41–43 (2016) 2. Myamlin, S.V., Baranovskiy, D.N., Kebal, I.Yu.: Kryishka lyuka universalnogo poluvagona. Byulleten nauch. rab. BryanskogofilialaMIIT Sb. nauch. rabot 7, 45–48 (2015) 3. Fomin, O., Kulbovskiy, I., Sorochinska, E., Sapronova, S., Bambura, O.: Experimental confirmation of the theory of implementation of the coupled design of center girder of the hopper wagons for iron ore pellets. Eastern Eur. J. Enterp. Technol. 5(1), 11–19 (2017). https://doi.org/10.15587/1729-4061.2017.109588 4. Okorokov, A.M., Fomin, O.V., Lovska, A.O., Vernigora, R.V., Zhuravel, I.L., Fomin, V.V.: Research into a possibility to prolong the time of operation of universal semi-wagon bodies that have exhausted their standard resource. Eastern Eur. J. Enterp. Technol. 3/7(93), 20–26 (2018). https://doi.org/10.15587/1729-4061.2018.131309

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5. Myamlin, S., Lingaitis, L.P., Dailydka, S., Vaičiūnas, G., Bogdevičius, M., Bureika, G.: Determination of the dynamic characteristics of freight wagons with various bogie. Transport 30(1), 88–92 (2015) 6. Gorbunov, M., Gerlici, J., Kara, S., Chernyak, G., Nozhenko, O., Kravchenko, K., Lack, T.: New principle schemes of freight cars bogies. Manuf. Technol. 18(2), 233–238 (2018) 7. Fomin, O.V., Lovska, A.O., Plakhtii, O.A., Nerubatskyi, V.P.: The influence of implementation of circular pipes in load-bearing structures of bodies of freight cars on their physicomechanical properties. Sci. Bull. Nat. Min. Univ. 6, 89–96 (2017) 8. Lovska, A.A.: Peculiarities of computer modeling of strength of body bearing construction of gondola car during transportation by ferry-bridge. Metall. Min. Ind. 1, 49–54 (2015) 9. Placzek, M., Wrobel, A., Buchacz, A.: A concept of technology for freight wagons modernization. In: 20th Innovative Manufacturing Engineering and Energy Conference. IOP Conference Series: Materials Science and Engineering, vol. 161, pp. 1–12 (2016) 10. Hauser, V., Nozhenko, O.S., Kravchenko, K.O., Loulová, M., Gerlici, J., Lack, T.: Car body and bogie connection modification for track curves pass ability improvement. In: MATEC Web of Conferences, vol. 157, 14 March 2018 11. Feodosev, V.I.: Soprotivlenie materialov. Uchebnoe posobie dlya vuzov, pp. 398–399. Izdvo MGTU im. N. E. Baumana, Moskva (1999) 12. Alyamovskiy, A.A.: SolidWorks/COSMOSWorks 2006–2007. Inzhenernyiyanaliz metodom konechnih elementov, pp. 398–412. DMK, Moskva (2007) 13. Railway applications – structural requirements of railway vehicle bodies - Part 2: Freight wagons. EN 12663-2 14. Steišūnas, S., Bureika, G., Vaičiūnas, G., Bogdevičius, M., Lunys, O.: Estimation of ambient temperature impact on vertical dynamic behaviour of passenger rail vehicle with damaged wheels. J. Mech. Sci. Technol. 32(11), 5179–5188 (2018)

Study of Dynamic Loads in the Wheel and Rail Contact Influence on the Maximum Adhesion Coefficient Nikolai Gorbunov1(&), Gintautas Bureika2, Maksim Kovtanets1, Gediminas Vaičiūnas2, Olga Prosvirova1, and Oksana Sergienko1 1

2

Volodymyr Dahl East Ukrainian National University, Central Avenue 59a, Sewerodonetsk 93400, Ukraine [email protected], [email protected], [email protected], [email protected] Vilnius Gediminas Technical University, Plytinės 27, 10105 Vilnius, Lithuania {gintautas.bureika,gediminas.vaiciunas}@vgtu.lt

Abstract. A scientific method for estimating the effect of dynamic loads arising at the wheel and rail contacts during locomotive movement is proposed, which most accurately describes the behaviour of a real rolling stock and complies with existing standards on the criteria of vertical and horizontal dynamics, as well as indicators of the movement stability. The dependences allowing illustrating the influence of the coefficient of vertical dynamics and relative horizontal slip on the tractive qualities of a locomotive are obtained. Keywords: Railway transport
Wheel-Rail contact
Adhesion coefficient Slip & slide
Dynamic coefficient
Safety factor for friction




1 Introduction The main priority of the development of railway transport is to increase the speed of the rolling stock, which is justified by increase in passenger and goods traffic. At the same time, the main areas of research can be considered as an increase in traction and dynamic qualities of rolling stock, provided that traffic safety is ensured. When studying traction on mathematical models, modeling the locomotive boxing introduces a number of assumptions, as a result of which the physical coefficient of adhesion is considered as the friction coefficient. This is usually associated with a large amount of mathematical calculations and time-consuming. In real conditions of locomotive movement, accompanied by dynamic interaction of wheelsets with rails, a number of factors arise that significantly reduce the maximum coefficient of adhesion of the locomotive relative to the physical. Therefore, the reason for the drawbacks of the known methods is the need to take into account both experimental and theoretical studies of unsteady undercarriage motion modes. In connection with the foregoing, the creation of a methodology for assessing the impact of dynamic loads that occur in the wheel and rail contacts during locomotive movement on their coupling qualities, which most accurately describes the behaviour of a real undercarriage, and complies with © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 235–244, 2020. https://doi.org/10.1007/978-3-030-38666-5_25

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existing standards on the criteria of vertical and horizontal dynamics, as well as stability indicators movement is an urgent task [1].

2 Overview of Information Sources Analysis of studies devoted to the problem of wheel and rail interaction proves that the traction and dynamic characteristics of undercarriage movements, resistance forces and traffic safety depend on the processes that occur in the wheel-rail contact [1, 2]. There are a large number of works devoted to the study of the effect of speed on the maximum realizable coupling coefficient of a locomotive [2]. The decrease in traction capabilities of the wheel contact with the rail with increasing rolling speed is explained by two main reasons. First, an increase in the intensity of dynamic processes in the wheel-rail system. Second, the phenomena associated with the duration of the contact, the plasticity of the wheel and rail materials. Conducting research on the model of a pair of wheels in 1:5 full size, determined the characteristics of adhesion under constant and variable loads from the wheel to the rail. It is noted that the friction coefficient decreases under variable load by 40% [3]. Tests carried out in [1] showed that the maximum adhesion force implemented by the locomotive is lower than the limit due to dynamic effects, and decrease in the coefficient of adhesion on the butt track is 8…27%, and on the joint path – 4…17% depending on the movement speed [2]. Rail joints as the main irregularities of the track have the most significant effect on the dynamic pattern of loads in contact. The second most important factor can be considered the wave-like nature of the rolling surface of the rails. Analysis of existing studies related to the assessment of the impact of dynamic loads occurring in the wheel-rail contacts on the maximum adhesion coefficient shows that the solution to this problem should be carried out on the basis of an integrated approach that most accurately describes the behaviour of a real undercarriage.

3 Emphasizing the Unsolved Problem Coupling has a complex physical nature of the contact molecular-mechanical interaction of wheels and rails. Moreover, the locomotive is a complex dynamic non-linear oscillatory system, subject to random disturbances, which makes it difficult to numerically determine the forces responsible for adhesion. Numerous factors affect adhesion stability, including specific for different roads: types and parameters of locomotives and ways, their technical condition; operating modes and speeds of locomotives and trains; climatic and weather conditions, etc. Calculation of traction qualities is also a technical and economic problem, which is solved from the standpoint of conflicting requirements: on the one hand, with increasing load from the wheel set on the rails, weight standards and carrying capacity of roads increase, which increases efficiency and traction performance, and on the other, damage increases rails, wear of tires and rails, which reduces the efficiency of the rolling stock. It is known that 98% of cases of rail breaks occur by contact stresses, and wheel slip at 90% determines wear and service life of wheel pairs. According to statistical observations of electric

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locomotives for every 10 thousand km, the thickness of the tires decreases from 0.5 to 1.5 mm [4, 5]. All this together creates uncertainty and complicates the construction of a design model of traction force on the adhesion, which would be quite reliable and universal to account for factors acting on the entire network of roads, and, finally, satisfying the technical and economic requirements.

4 Methodology of the Research When choosing a design scheme, a mathematical model should most accurately describe the particular behavior of a real undercarriage and, at the same time, due to correct simplification and the introduction of reasonable assumptions, it should be fairly simple to conduct computer studies. A wheel-motor unit (WMU) with an aftersuspension spring suspension was adopted as the design scheme, on which the frame of the bogie with a mass equal to 1/6 of the body weight plus 1/3 of the mass of the frame of the 2TE116 locomotive truck was installed. In this case, the following assumptions were made: the characteristics of elastic and dissipative elements in the mates of the pair of wheels with the bogie frame are assumed to be linear; all elements in the system are treated as absolutely solid bodies; the galloping of the bogie frame is neglected, and the change in the vertical axle load caused by the galloping in a real locomotive is taken into account when considering bouncing oscillations; angular stiffness of axle harnesses in the longitudinal-vertical plane is taken into account when choosing the stiffness of the springs of the first stage of spring suspension; the damping characteristics of spring suspension elements are assumed to be linear with respect to the strain rate; there are no gaps in the motor-axial bearings in the radial and transverse direction; the suspension of the nose of the traction motor is made rigid; the presence of a gap between the end face of the axle and the axle box is neglected; it is assumed that there are no gaps in the engagement of the drive train; the external characteristic of the traction motor in the vicinity of the operating point is assumed to be linear; the slope of the rolling surface of the band is adopted variable and is taken into account by the value of the equivalent slope depending on the position of the contact point; the magnetic interaction between the armature and the stator TE, which causes the occurrence of the traction moment is modelled by the application of two external oppositely directed torques, one of which is applied to the anchor, the other to the stator; resistance to movement from the composition is modelled by applying to the frame of the cart a force directed against the movement of the undercarriage; according to studies [4] and taking into account that movement is being investigated up to speeds of 50 km/h, the path is taken in the form of two sections of rails lying on the ground, equally-elastic in the vertical and transverse directions; the base is able to resist forces acting both down and up; deformations of the base are equal to the corresponding movements of the rails at the points of contact of the wheels; the mass of the path under each wheel is taken according to [5–8] to be equal to the mass of the rail with a length of 4 m. The design scheme includes six solids: a bogie frame, a wheel set with a gear wheel and axle boxes, a stator anchor for the traction power train and rails. Considering the accepted assumptions, we introduce the notation for their movements (Table 1, Fig. 1).

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TE stator TE anchor Rails Xd Xa – !d !a !rj Zd Za Zrj ud ua – hd ha – kd ka –

Fig. 1. The WMU design scheme.

In the general case, the configuration of the system under study is described by 33 coordinates. To describe the design features of WMU, taking into account the accepted assumptions, we impose on the system the corresponding constraints in the form of equations describing the dependencies between displacements of individual elements. The design of WMU with support-axial suspension of the traction motor causes the following of them: 1. the equality of movement of the wheelset, the stator and the armature of the traction motor in the direction of coordinates X; h; k X 0 ¼ X d ¼ X a ; h0 ¼ hd ¼ ha ; k0 ¼ kd ¼ ka ; 2. connection of lateral displacements of the same elements by the formulas

ð1Þ

Study of Dynamic Loads in the Wheel and Rail Contact Influence

Ya ¼ Y0  k0
‘a ; Yd ¼ Y0  k0
‘d ;

239

ð2Þ

3. connection of vertical displacements with displacements of TE, anchor and wheel axle Zd ¼ ð1 

‘d Z k1 þ Z k2 ‘d ‘a Z k1 þ Z k2 ‘a þ
Zb ; Za ¼ ð1  Þ
þ
Zb ; Þ
‘b 2 ‘b ‘T 2 ‘b Zb ¼

‘T i 1
‘b
u0 
ðZk1 þ Zk2 Þ:
ua  1þi 2 1þi

ð3Þ ð4Þ

Among the generalized forces acting on the system, we can distinguish external forces that have a unilateral effect on the elements of the system, and internal, always paired. External forces include train resistances and the returning moment applied to the bogie frame, and longitudinal traction forces acting at the wheel and rail contacts [9]. Depending on the mode of movement being studied (acceleration, movement at a constant speed, braking), the resistance force of the train can be assigned values that are smaller, equal or greater than the traction force. The thrust force, in turn, depends on the power implemented on the mode of motion: FT ¼

Nd
i ; R0
#d
ua

ð5Þ

where Nd – power sold TE in accordance with the position of the controller-driver; i – ratio of reducer gear; R0 – average wheel radius; #d – stiffness coefficient traction characteristics; ua – the angular velocity of rotation of the anchor TED. The expression for the coefficient of use of the adhesion, obtained experimentally in [5], has the form: wxj ¼ w0 ¼

ae2xj

exj 1 ; 2 þ b exj þ c deyj þ 1

ð6Þ

where exj – longitudinal and transverse sliding. exj ¼

y_ kj  y_ pj  k0
x_ 0 u
R j  xk ; eyj ¼ ; u
Rj u_ kj
Rj

ð7Þ

where Rj – the radii of the rolling surfaces of the wheels; u; x_ k ; y_ kj ; y_ pj – angular, longitudinal and transverse velocities of the wheels and rails; a, b, c, d are constants. The radii of the rolling surfaces of the left and right wheels are determined by the mutual position of the wheelset and the track in the transverse direction: Rj ¼ R0 þ DRj ;

ð8Þ

where DRj is the change of wheel radius in the process of winding movement of the wheelset

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DRj ¼ ð1Þ j
ykj  ypj  hrt
kej ;

ð9Þ

where ykj–ypj – lateral displacement of the tires and wheels tires at the points of contact relative to the origin of the system; kej – effective taper of the tires at the points of contact; hrt – horizontal rail roughness. A number of generalized forces that cannot be taken into account when drawing up equations by the Lagrange method are presented as internal forces. Such internal forces will be considered as the torque and reactive moments of the TE and shear forces in the contacts of the wheels with the rails applied to the rails and tires. The torque TE on the external characteristics of the locomotive is changed according to the law Md ¼

Nd : u_ a
vd

ð10Þ

Depending on the mode of motion under study (starting, acceleration, driving at a constant speed in the thrust and on coasting) a certain value of the power of the TE (Nd) is selected. The transverse cohesive forces in the contacts, as well as the longitudinal, are determined by the experimental dependencies: Fyj ¼ Phj
w0
Kyj  ð1Þ j
Phj ;

ð11Þ

where Kyj is the longitudinal use ratio of the adhesion; Phj – horizontal or gravitational component of the vertical wheel load on the rail. Kyj ¼

eYJ 1
; f
e2yj þ q h
exj

ð12Þ

where exj – relative lateral slip in the contacts of the ear with the rails; f, q, h – constants. Accounting for the gravitational lateral force makes sense due to the variable taper of the surfaces of the wheels kej: Pgj ¼ Pj
kej :

ð13Þ

The vertical load in the contacts of the wheels with the rails can be described depending on the parameters of the rails: Pj ¼ P0  mr
Z€r  bP
Z_ rj  br
Zrj :

ð14Þ

Equations of motion are compiled using the Lagrange equations of the second kind d dK dD dP ð Þþ þ ¼ QK ; dt d q_ K d q_ K dqK

ð15Þ

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where qk ; q_ k – generalized coordinates and speeds of movement of system elements; Qk – generalized forces; K, P, D – kinetic, potential and energy dissipation of a mechanical system. The kinetic energy of the undercarriage is equal to the sum of the kinetic energies of the system of bodies entering it, moving along independent coordinates. The results of calculations to determine the traction qualities of the wheel-motor unit are presented in Figs. 2, 3, 4, 5 and 6. Since the influence of fluctuations of the vertical dynamic load and relative horizontal slips in the contacts of the wheelset with the rail on its traction qualities is investigated, at the first stage of the research, the dependence of Kg and ey on the speed of movement was revealed (Figs. 2 and 3). At the same time, ey is determined for three values of the returning moment Mb ¼ Ssp
kb , where kb is the rotation angle of the bogie (1 – Ssp = 64 kN/mm; 2 – Ssp = 96 kN/mm; 3 – Ssp = 148 kN/mm). At the second stage of research, dependencies of the coefficient of safety on adhesion s0,7, with a normalized value of thrust coefficient K0 = 0,7, on the speed of movement (Fig. 4), and also s0,7 dependence on the coefficient of vertical dynamics and relative horizontal slip were obtained. (Figures 5 and 6). In the course of the calculations, the integration procedure described in the article was carried out, and the graphs were based on the mean value of s0,7 [10–12].

Fig. 2. Dependence of the coefficient of vertical dynamics on the speed of movement.

Fig. 3. The dependence of the relative lateral slip of the wheelset on the speed of movement.

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Fig. 4. The dependence of the safety factor of adhesion on the speed of movement.

Fig. 5. The dependence of the safety factor of the coupling of the coefficient of vertical dynamics.

Fig. 6. The dependence of the safety factor of adhesion on the relative lateral slip.

5 Conclusions 1. A method is proposed for assessing the impact of dynamic loads that occur in the wheel-rail contacts during locomotive movement, which most accurately describes the behavior of a real undercarriage and, due to correct simplification and the introduction of reasonable assumptions.

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2. As a result of mathematical modeling of WMU motion using a criterion such as a adhesion margin (s0,7) to assess its traction, dependences were obtained that illustrate the effect of the vertical dynamics coefficient and relative horizontal slip on the locomotive traction qualities. 3. From the analysis of the dependences obtained, it follows that with an increase in the speed of movement of the wheel-motor unit, the coefficient of vertical dynamics and the relative horizontal slip increase. In the speed range of 5…50 km/h, Kg increases from 0.075 to 0.18 and ey increases from 0.08…0.152 to 0.225…0.25. In this case, the greater the stiffness of the connection of the body with the locomotive cart, the smaller the horizontal lateral slip of the wheel pair in the rail track. So at a speed of 5 km/h ey for Mb3 is 48% less than for Mb1 (curves 3 and 1 in Fig. 3, respectively), and for a speed of 50 km/h, this difference decreases by 12%. The safety factor of adhesion decreases with increasing speed, Fig. 4, which is caused by an increase in the oscillations of the vertical dynamic load and the relative horizontal slip (Figs. 2 and 3). At the same time, with an increase in speed from 5 to 25 km/h, a decrease of s0,7 is less intense than with an increase in speed from 25 to 50 km/h. So in the range of change of speed 5…25 km/h s0,7 varies from 0.97…0.9 to 0.947…0.886 and in the range of 25…50 km/h to 0.853…0.81. With the increase of turning moment, the effect of speed on the safety factor of the adhesion becomes less significant, and s0,7 with Mb3 is 6…7% more than with Mb1 (Mb3 > Mb1). Thus, with an increase in the speed of motion of the WMU, and hence with an increase in the oscillations of the vertical dynamic load and the relative horizontal sliding of the wheelset along the rails, the safety factor of the adhesion decreases significantly. At a speed of 25 km/h, the reduction is 5…12%, at a speed of 50 km/h – 15…19%. The change in the safety factor of adhesion depending on the coefficient of vertical dynamics is presented in Fig. 6, and from the relative horizontal cross slip – in Fig. 6. The presented dependences show that with an increase in the dynamic coefficient from 0.05 to 0.2, the safety factor for adhesion decreases from 0.97 to 0.925, i.e. by 4.5% with an increase in the relative lateral slip from 0.075 to 0.25%–0.97…0.92. Acknowledgment. This research was funded by a grant (No. S-LU-18-12) from the Research Council of Lithuania. This research project “EFFECT-RAIL” was performed in cooperation with the Volodymyr Dahl East Ukrainian National University, Ukraine.

References 1. Gorbunov, M., Pistek, M., Kovtanets, O., Nozhenko, S., Kara, P., Kučera, P.: Research to improve traction and dynamic quality of locomotives/JVE international LTD. Vibro Eng. Procedia 13, 159–164 (2017). ISSN 2345-0533 2. Gorbunov, N.I.: Increase of traction qualities of diesel locomotives at the expense of improvement of elastic ties of bogies, Ph.D. disseration, Dnipropetrovsk (1987). 180 p. 3. Voronin, S.V., Karpenko, S.S., Volkov, O.V., Bacchin, K.O.: Analysis of work on friction and clutch control in the «wheel-rail» contact. UkrAZZ Scientific Papers, no. 141, pp. 247– 253. UkrDazT, Kharkiv (2013)

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4. Gorbunov, M., Kovtanets, A., Kostyukevich, V., Nozhenko, O., Vaičiūnas, G., Steišūnas, S.: Development of the theory and methodology of controlling the local tribological contact thermomechnical loading. In: The Proceedings of the 22nd International Scientific Conference. Transport Means, Trakai, Lithuania, 03–05 October 2018, pp. 1383–1388 (2018) 5. Dusza, M.: The wheel-rail contact friction effect on high speed vehicle model stability. Transp. Probl. 10(3), 73–86 (2015) 6. Macheret, D.A.: Economic significance trends and prospects for increasing the speed of traffic on railway transport. Bull. OUS JSC «Russ. Railw». 2, 13–23 (2013) 7. Gorbunov, M., Pistek, V., Kovtanets, M., Nozhenko, O., Kara, S., Kučera, P.: Supplying system abrasive material with automatic dosing control. Vibroeng. Procedia 18, 207–214 (2018). ISSN PRINT 2345-0533 8. Gorbunov, N.I., Slashchev, V.A., Kovtanets, M.V., Kravchenko, E.A.: Experimental justification for choosing an effective method for increasing the clutch in the wheel-rail system. Railw. Transp. Ukr. 3/4, 48–51 (2012) 9. Dyomin, Yu.V., Chernyak, G.Yu.: The dynamics of an empty car and the safety of the train. Railw. Transp. Ukr. 3, 50–52 (2007) 10. Gorbunov, N., Kovtanets, M., Prosvirova, O., Garkushin, E.: Adhesion control in the system of «wheel rail». Silesian Univ. Technol. Fac. Transp. (Poland) Transp. Probl. 7(3), 15–24 (2012) 11. Kostukevich, A., Gorbynov, N., Nozgenko, V., Kovtanets, M., Tsiganovski, I.: Friction interaction management in two-point “wheel-rail” tribocontact. Silesian Univ. Technol. Fac. Transp. (Poland) Transp. Probl. 7(3), 53–59 (2012) 12. Vaičiūnas, G., Bureika, G., Steišūnas, S.: Research on metal fatigue of rail vehicle wheel considering the wear intensity of rolling surface. Eksploatacja i Niezawodnosc Maint. Reliab. 20(1), 24–29 (2018)

The New Simulation Approach to Tramway Safety Against Derailment Evaluation in Term of Vehicle Dynamics Dariusz Kalinowski1(&) , Tomasz Szolc2 and Robert Konowrocki2 1

,

PESA Bydgoszcz SA, Zygmunta Augusta 11 Str., Bydgoszcz, Poland [email protected] 2 Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B Str., Warsaw, Poland

Abstract. The existing European standard EN 14363 covers all necessary tests for different railway vehicles, but it is inadequate for tram vehicles, especially in safety against a derailment examination. Its operational conditions are much different. Trams overcome horizontal curves with much smaller radii than railway vehicles. There is a large diversity in wheel-rail pairing, i.e. almost every public transport operator uses a different wheel profile. In the running gear design much more rubber-metal elements are used in order to ensure a low-floor interior and to keep the kinematic envelope. Apart from standard vehicle configuration, i.e., a carbody on two bogies, in modern tram designs numerous arrangements are applied: wagons with one outer bogie, wagons with one centered bogie, wagons without bogies (sedan) etc., where twisting shims cannot be used to achieve the required twist. The described issues imply that the methodology of safety against derailment described in EN 14363 standard cannot be applied without any modifications. This paper presents a new proposal for a simulation safety against derailment for a vehicle with an arbitrary configuration of wagons and running gears. The numerical analyses have been performed by means of the Simpack Rail software. Keywords: Safety against derailment
Tram vehicle
Numerical simulation Running dynamics
Simpack rail software




1 Introduction Safety of railway vehicles is the subject of investigation for researchers worldwide [4, 8, 12, 13, 15]. In many cases, the main mechanism causing the derailment of the vehicle is a loss of lateral stability [1, 10]. Such phenomenon causes an increase of transverse force value in the wheel-rail contact zone. It may occur due to various conditions resulting the loss of lateral track guidance during a normal operation of the vehicle. It should be mentioned: raise of the wheel flange, track gauge widening, rail inclination, track condition like reduction of lateral stiffness of rails fastening system and sleepers anchorage system [7]. In most cases the assessment criteria of safety against derailment are based on the values of derailment index Y/Q, wheel unload factor and wheel raise Dz. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 245–254, 2020. https://doi.org/10.1007/978-3-030-38666-5_26

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This publication is an introduction to the study of light rail vehicles to classify the impact of their design on safety against derailment issues. At this stage of the work, an identification of key features of the vehicle design and numerical simulations of vehicle dynamics were carried out, focusing on the safety against derailment index Y/Q.

2 Numerical Simulations of Tram Vehicle Dynamic Behavior 2.1

Physical and Numerical Model

In order to check theoretical values of forces in the wheel-rail contact zones, computerbased models of three tram vehicles were built. Generally, the physical models of these vehicles were treated as a system of rigid bodies joined together by means of flexible and damping elements. This approach to modeling is called the multibody simulation (MBS) method [5, 14] and is very often used in the commercial software, i.e. Vampire, Adams/Rail, VI-grade/VI-Rail, Autodyn and Simpack Rail. In this method, the structural elements of the vehicle are assumed as non-deformable bodies and suspension elements are modelled as flexible elements [2, 3]. Movement limitations of these bodies result from imposed constraints [11]. To verify safety against derailment, simulation models of tram vehicles were prepared in various configurations shown in Fig. 1. Different kinds of inter-carbody couplings were also considered here (Fig. 1). A

β1, γ1

β1, γ1

α2, β2, γ2

α2, β2, γ2

B

α2, β2, γ2

α2, β2, γ2

C

β1, γ1

γ1

α2, β2, γ2

α2, β2, γ2

Fig. 1. Tram configurations for safety against derailment with inter-car couplings designation: (A) – 3-car articulated tram with non-swiveling bogies; (B) – 3-car articulated tram with swiveling bogies; (C) – 3-car articulated tram with centered non-swiveling bogies.

In tram configurations A, B and C the wheelset was modeled as a classic solution. Presented trams were equipped with identical lower joints of adjacent carbodies

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(ball joints) a2, b2 and c2, but the upper connections vary, which is indicated by the symbols of angular degrees of freedom a1, b1 and c1 (Fig. 1). Each symbol refer to the rotational movements of an exact point with regards to axes x, y and z respectively. In order to ensure safe operation and stability of the vehicle, in most cases it is necessary to use an upper coupling that allows adjacent carbodies to rotate around the transverse axis y. Such technical solution allows to negotiate vertical curves (convex or concave) without collision with infrastructure elements. It could be achieved by using so-called Panhard’s rods. Such connection was implemented in the tram C between carbodies 1 and 2. In tram C instead of top joint inter-carbody hydraulic dampers were introduced in order to diminish the relative movements of adjacent carbodies. Each of the tram simulation models was divided into three basic elementary groups, which are wheelsets, bogie frames and carbodies. The wheelset was assumed as a rigid body with three degrees of freedom (DOF). The bogie frame is represented by a rigid body with five degrees of freedom, and the carbody model has five degrees of freedom, as well. By taking into account the constraints of inter-carbody couplings, the tram models created for numerical tests were respectively with: A – 29 DOF, B – 55 DOF and C – 40 DOF. Motion of the models of the tram vehicles are described by a system of differential equations. Motion of such structures of tram vehicle is mathematically described by means of second order ordinary differential equations. Assuming that oscillations of each particular tram model relative to the reference system can be regarded as small, such motion can be described by means of the system of linear equations formulated here – in the matrix form:  2 2  Md =dt þ Cd=dt þ K
q ¼ F;

ð1Þ

where q denotes the vector of generalized coordinates; M is the symmetrical mass matrix; C describes the damping matrix; K is the stiffness matrix; F denotes the force vector and d/dt is the differential operator. By using the Newmark methods a respectively system of linear algebraic equations is created. This system of equations is solved with a time step of Dt = 0.1 s. The scheme of the physical model of the single tram carbody with the bogie is shown in Fig. 2. MCB, ICB

Φ

Θ

MCB, ICB Y

X Z cII cI

dI

Z cII

dII MBF, IBF cI dI

mW

cI

dII dI

cII

MBF, IBF cI dI

mW wheel-rail contacts

wheel-rail contacts

Fig. 2. The physical vehicle model in general form.

dII

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Depending on the number of bogies and used carbodies, the presented model can be properly complicated. 2.2

Wheel-Rail Contact Model

The mathematical models of tramway vehicles have been integrated with the algorithms and numerical procedures that determine the wheel-rail contact. The numerical procedures for wheel-rail contact were used to determine the values of forces and their areas of operation in contact zones. The contact model was based on the simplified Kalker’s theory and the FASTSIM algorithm [9]. To calculate tangential contact forces, normal pressure forces were determined, friction coefficient was assumed equal 0.36, the length of the semi-axis a and b of the contact area ellipse was calculated using Hertz’s theory [6]. The tangential contact forces Tx and Ty were determined using the FASTSIM procedure. The contact geometry parameters depending on the transverse displacement of a particular wheel as input values to the FASTSIM procedure have been show in (Fig. 3). This approach reduced the calculation time of vehicle motion dynamics simulation. The nominal PST profile shape (according to standard [17]) was assumed as a wheel profile and Ri60N profile shape was used for rails in simulation models for testing dynamic properties of tram vehicles. The contact geometry of modelled tram wheel/rail is shown in Fig. 4.

Fig. 3. Parameters of wheel-rail contact geometry for the wheel profile PST and rail profile Ri60N as a function of wheelset lateral displacement y.

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Fig. 4. Contact point of the wheel profile PST and rail profile Ri60N.

2.3

Simulation Cases

Safety against derailment of railway vehicles is defined in standard EN 14363:2016 [16], but it does not apply to light trams. To confirm the safety of railway vehicle negotiating small radius curves, the safety against derailment index Y/Q is determined and measurements of guiding wheel lift Dz is performed. The tests take place on a curved track with radius R = 150 m one, with 3% twisted section. In accordance with EN 14363, the twist is achieved by changing the height of outer rail. Here, a typical UIC60 rail profile is used. EN 14363:2016 [16] recommends that safety against derailment tests should be carried out on a track with gauge of 1,440–1,465 mm. During tests on a twisted track it is also necessary to measure a friction coefficient between wheel and rail as well as a wheel/rail contact angle. The friction coefficient determined in this way is used to assess a validity of guiding force and vertical force measurements. A combination of the wheel/rail contact angle and the static wheel load (values measured before the safety derailment test) is used to determine the friction coefficient on the dry rails T dry, according to the methodology given in EN 14363:2016 [16]. The minimum wheel-rail friction coefficient for which the safety against derailment test is valid is equal to 80% of the friction coefficient on dry rails. For each tested vehicle, the least-convenient load combination and non-linear stiffness of the suspension elements should be determined. The most unfavorable case is a condition of empty vehicle, where the wheel loads are the smallest. EN 14363 [16] also requires additional twist of bogies and carbodies, implemented with shims in the primary and secondary suspension. The standard EN 14363 [16], as already mentioned in the paper, does not apply to trams. The methods presented there cannot be directly referred to these vehicles. The classic trams and their low-floor varieties have much more complex kinematic systems than railway vehicles. The trams operate most often in the urban area, during ride negotiating horizontal curves with much smaller radii than the required by standard (nominal radius of test track R = 150 m) [16]. Such a normative curve does not have to be a critical curve radius of track for tram vehicles. In view of the above, due to the lack of normative guidelines, the authors developed an original methodology for testing safety against the derailment of trams on curves with various radii. The track geometry was defined on the basis of the document “Technical guidelines for the design and maintenance of tram tracks” [18], which defines the radii of track curves used in to Polish tram systems and it provides the minimum and recommended cant value for these arcs (Table 1).

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Trams are equipped with a significant number of rubber and metal elements, which stiffness values depends on manufacturing tolerances and atmospheric conditions. This was taken into account by introducing a stiffening factor for rubber-metal elements equal to 2 for each of the simulation cases. For simulation purposes, uniformity of mass distribution on the right- and left-hand side of the tram has been assumed. Therefore, safety against derailment was only tested for the right-hand curve.

3 Results of Numerical Simulation The purpose of this work was to present the development of safety against derailment index for each tram wheel in various configurations as a function of the track gauge and horizontal curve radius. As the original contribution of the paper to the numerical studies a different track configuration has been assumed than the track defined in the standard [16]. The simulation scenarios were defined for a combination of: 5 different track gauges, 4 different horizontal curve radii and 3 various tram configurations (with classic wheelsets), which gave a total number of 60 simulation cases. The critical load case of the vehicle’s operational configuration was assumed, i.e. a tram in the empty condition. During simulation vertical Q and lateral Y wheel forces were recorded in the wheel/rail contact region. On the basis of these forces in the contact zone, safety against derailment indexes Y/Q were determined as the maximum value of the ratio of transverse force to the vertical wheel load force. This criterion is based on the contact force equilibrium in the inclined plane of contact between the wheel and rail, and for the assumed wheel profile PST and friction coefficient. Its limit value is determined from relation (2): tga  l jY j  ; jQj 1 þ l
tga

ð2Þ

where a denotes the wheel flange inclination angle; and l is the wheel-rail friction coefficient. For the wheel flange inclination angle a = 70° of the assumed the wheel profile PST and for the predefined friction coefficient l = 0.36, the limit of safety against derailment index is (Y/Q)lim = 1.20. An exceeded limit value may result in an increased probability of the derailment. Safety against derailment indexes Y/Q for each wheel of the investigated tram configurations as a function of the curve radius and track gauge, is shown in Figs. 5, 6 and 7. The results for the first bogie of each tram type are presented in these figures. In the figures each wheel has its own two-letter index i.e. – the first letter is responsible for the location of the front/rear wheelset (F/R) while the other second one defines the left-/ right-hand side (L/R).

The New Simulation Approach to Tramway Safety Against Derailment Evaluation

Fig. 5. Y/Q index for the first bogie of tram type A.

Fig. 6. Y/Q index for the first bogie of tram type B.

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Fig. 7. Y/Q index for the first bogie of tram type C.

The motion of trams on curves with small radii results in higher values of Y/Q index than in the case of larger radii. There was no definite answer in the dependence between safety against derailment index and track gauge, however, the research results showed a significant trend. It indicates that simultaneously with the track gauge increase the Y/Q index for attacking wheel decrease (FL wheel for the right-hand curve of the railway) and for the wheel located diagonally to the guide wheel, i.e. RR wheel, while it increased for the FR and RL wheels (Figs. 5 and 6). The increase of the spacing of the rails on a tramway track affects wheel flange-rail clearance extension and it reducing the distance between outer side of wheel flange and rail groove. The simulation results presented in the form of graphs shown in Figs. 5, 6 and 7 lead to conclusion that the guidance is transferred to the wheel on inner side of curve, resulting in an increase of the transverse force at the contact point. Despite the high Y/Q values achieved, there was no risk of derailment with no wheel lift. It was a consequence of the fact that the outer side of the flange from rail groove is more inclined, i.e. ca. 79° for the wheel profile PST than the inner side.

4 Summary and Conclusion In the paper an important issue of safety against a derailment of the light railway vehicles has been raised. The investigations of vehicle-track dynamic interactions were performed by means of numerical simulations. Based on the obtained computational results, an essential influence of various municipal tramway vehicle designs and configurations on wheel-rail contact forces, in particular, on the derailment factor Y/Q, is discussed. The simulation results confirm the assumption that the track conditions for

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safety against derailment described in standard [16] addressed to the railway vehicles are not suitable for investigations of the light municipal trams. In the mentioned standard the minimal radius of the test track arc is equal to R = 150 m. With such track curvature the considered vehicles did not indicate any exceeding of the limit value of the derailment factor Y/Q. But here, for various municipal tram track curvatures assumed for several simulation scenarios, significantly worse derailment factor values have been obtained. From the simulation results it follows that the derailment factors Y/Q corresponding to various tramway designs become too large at low values of track curvature radii together with a rise of the track gauge. Moreover, an application of swiveling bogies in the tram vehicles leads to an improvement of their dynamic properties of running on tracks with curvatures typical for the municipal conditions. Thus, one can remark that relatively low travelling speeds of trams do not guarantee a sufficient safety against derailment. Basing on the results of numerical simulations carried out in a framework of this research, it should be concluded that a need of development of some new testing procedures regarding an approval of tramway vehicles for operation is very required. But anyway, one ought to be conscious that this article does not cover a full safety analysis against derailment of all designs and configurations of tramway vehicles, in particular of these characterized by wheelsets with independently rotating wheels. A development of testing procedures addressed to such unconventional solutions is still in progress.

References 1. Bogacz, R., Konowrocki, R.: On new effects of wheel-rail interaction. Arch. Appl. Mech. 82, 1313–1323 (2012) 2. Bogdevičius, M., Žygienė, R.: Research of dynamic processes of the system “vehicle – track” using the new method of vehicle wheel with metal scale. Eksploatacja i niezawodność – Maintenance Reliab. 20(4), 638–649 (2018) 3. Dailydka, S., Lingaitis, L.P., Myamlin, S., Prichodko, V.: Mathematical model of spatial fluctuations of passenger wagon. Eksploatacja i niezawodność – Maintenance Reliab. 4(40), 4–8 (2008) 4. Elkins, J., Wu, H.: New criteria for flange climb derailment. In: Proceedings of the ASME/IEEE Joint Railroad Conference, pp. 1–7 (2000) 5. Garcia de Jalon, J., Bayo, E.: Kinematic and Dynamic Simulation of Multibody Systems. Springer, New York (1994). 6. Hertz, H.: Über die berührung fester elastischer Körper (On the contact of rigid elastic solids). J. reine und angewandte Mathematik 92, 156–171 (1882) 7. Iwnicki, S. (ed.): Handbook of Railway Vehicle Dynamics. CRC Press Inc., Boca Raton (2006) 8. Kalinowski, D.: Current knowledge regarding safety against derailment (Aktualny stan wiedzy dotyczący zagadnienia bezpieczeństwa przed wykolejeniem, Pojazdy Szynowe). Railway Veh. 4, 44–53 (2013). (in Polish) 9. Kalker, J.J.: A fast algorithm for the simplified theory of rolling contact. Veh. Syst. Dyn. 11 (1), 1–13 (2007)

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10. Kardas-Cinal, E.: Running safety of a railway vehicle in the presence of random track irregularities. Pojazdy Szynowe 4, 1–10 (2012) 11. Konowrocki, R., Bajer, C.I.: Friction rolling with lateral slip in rail vehicles. J. Theor. Appl. Mech. 47(2), 275–293 (2009) 12. Opala, M.: Study of the derailment safety index Y/Q of the low-floor tram bogies with different types of guidance of independently rotating wheels. Arch. Transp. 38(2), 39–47 (2016) 13. Sato, Y., Matsumoto, A., Ohno, H., Oka, Y., Ogawa, H.: Wheel/rail contact analysis of tramways and LRVs against derailment. Wear 265, 1460–1464 (2008) 14. Shabana, A.: Dynamics of Multibody Systems, 3rd edn. Cambridge University Press, Cambridge (2005) 15. Weinstock, H.: Wheel climb derailment criteria for evaluation of rail vehicle safety, Paper no. 84-WA/RT-1, ASME Winter Annual Meeting, New Orleans, LA, November (1984) 16. EN 14363:2016 – Railway applications – Testing and Simulation for the acceptance of running characteristics of railway vehicles – Running behavior and stationary tests (2016) 17. PN-K-92016:1997 – Tram wheel sets, flexible – Surfaced tires – Requirements and testing (1997) 18. Technical guidelines for the design and maintenance of tram tracks, Ministry of Administration, Local Economy and Environmental Protection, Department of Public Transport and Roads, Warsaw (1983)

Modeling of Hybrid Autonomous Vehicle Fuel Consumption Imre Zsombók and Máté Zöldy(&) Department of Automotive Technologies, BME Technical and Economical University of Budapest, Műegyetem rkp 3, Budapest 1111, Hungary [email protected]

Abstract. Autonomous vehicles role in the road mobility is increasing day by day. Their propulsion system is not yet decided, our research focuses on plug-inhybrid vehicles that are merging the most relevant propulsion systems: the electric drivetrain and the internal combustion engine. Mileage and refueling of autonomous vehicles is a rarely investigated area, but it role in a successful implementation of autonomous vehicles is inevitable. In our research, we aiming to set up a model that describes the main influencers on vehicle energy balance and optimize its refueling according to drivers/owners preference. To test and simulate the model and simulation environment is a must. In our work we investigated three commonly used modeling software and according to its capabilities one was chosen for the first tests. In this paper we give a short outlook about the status of the research, the selection process of the simulation software and the first test results about fuel consumption. Keywords: Autonomous vehicles consumption
Modelling


Plug-in-Hybrid vehicles
Fuel

1 Introduction Autonomous and connected vehicles will unquestionably have a significant role in the near future of transportation. Plug-in-hybrid (PHEV) automobiles are the most complicated according to the state of art technology [1] in propulsion aspect. A few research only is aiming to construct energy economy and based on that refueling forecast for PHEV autonomous vehicles. Several environmental and on-board influencers have quantifiable and extrapolative influence on energy consumption and refilling [2]. On board vehicle parameters have in most of the cases minor influence on fuel consumption but these long term effect can be followed by trend analysis. Road related [3] and external environment parameters can be perceived with radars, and signals are processed within the vehicle in most of the cases [4]. Utilization related parameters are to be reached via CAN network of vehicle. A well established mixture of these data and signals is aimed to be the base of vehicles refueling decision extended with refueling stations data.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 255–262, 2020. https://doi.org/10.1007/978-3-030-38666-5_27

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2 Literature Overview Continuous development of vehicle design is one of the most important factors of uncertainty for the energy performance of autonomous and connected vehicles. In the literature a there is a huge difference regarding to identify which parameters should drive the automobile design optimization and decision-making procedures that will affect autonomous vehicles-related fuel and energy efficiency and emissions [5]. Not only life-cycle assessment based approaches but also several other studies as well about characterization of energy and environmental benefits of different autonomous vehicle designs under different real-world scenarios are it should be a first level priority to concentrate on quantifying energy efficiency developments that are achievable with state-of-the art autonomous vehicles. Special designed proving grounds and test facilities are necessary to able to demonstrate that at least a part of the theoretical energy saving of the connected and autonomous vehicles (CAV) is achievable [6]. Bhavsar et al. [7] work main aim was to understand and describe the energy reduction opportunities for connected and autonomous plug-in hybrid vehicles (PHEV). They defined and tested four energy saving strategies. The baseline strategy was the conventional human driver behavior. An optimized strategy was used the available knowledge of state of the art traffic signals in approaching intersections. Third scenario allowed for the test vehicle to use the information of all leading vehicles headway. The most developed fourth strategy enabled no only use headway information but any approaching light’s status was available as well. All four scenarios were simulated and energy consumption was estimated. For full adoption case a fuel consumption savings of 75% was reachable, 71% energy saving was found in case of intersection only strategy and 69% for the headway only strategy. Another research results [8] shows, that in case a vehicle follows a control algorithms that is designed without focus on energy economy performance could perform even worthier than a human driver, while control systems designed to focus on energy efficient decision could even exceed the reference human driver performance in EPA (Environment Protect Agency) fuel economy tests. As today there is no incentives for autonomous vehicle control algorithm developments, manufacturers may not have in focus to design for improved energy economy. They drivers of development of today are to maximize vehicle speed and acceleration. Wu et al. [9] investigation was focusing on partial automation potential energy saving effect. They investigated if vehicle is able to use the information of actual traffic signal status and it is able to schedule its intersection approach, compared to traditional human driver given the same type and amount of information. In case of manual drive the vehicle dashboard could propose velocities to approach the intersection and human driver would attempt to follow the guidance. During the test the speed profile of real human drivers were recorded. A speed profile was developed as next stage to demonstrate what would have been happened in case of guidance been followed faultlessly in the expected partial automation case. EPA’s standard vehicle simulator was used to simulate energy consumption. As result it was concluded, that partial automation could increase energy efficiency up to 5–7% compared to a traditional driver.

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Rajamani and Shladover paper [10] is focusing on cooperative adaptive cruise control (CACC) systems as they assumption is that these could ascertain a huge capacity increase and parallel decrease in headway possible. They state that a reduction of headway to 1 s result near a capacity doubling from the range of 3,000 vehicles/lane/hour for to 6400 vehicles/lane/hour. An adaptable ACC strategy could be as well an option. Such a system will able to adopt itself to actual traffic conditions and act according to the optimal way. In case of 5% of the vehicle will be equipped with such systems in can be followed with a tangible reduction in congestions. Setting variable speed limits for cooperative and self-driven vehicles reported as an efficient tool to moderate traffic patterns and improves energy efficiency. Connected and automated vehicles can positively effect delay time, fuel economy and emissions at intersections [11]. In a mixed environment of automated and nonsensor equipped vehicles they found that with ratio increase of vehicle that are ready for vehicle-to-infrastructure up to 16% savings are available [12]. Literature shows that driverless vehicles fuel consumption is researched mainly as following driver attitudes [7, 9] or handles the vehicle as part of a connected environment [10–12], main decision focus of self driving vehicles is rarely the emission and fuel consciousness [8]. We see that fuel consumption prediction and based on that in the future fuel recharging prediction of autonomous vehicles should be put more in the focal point of the researches. It will have effect not only on travelling habits but environmental load of self driving cars as well. As simulating environments has an increasing role in testing, validation and homologation of autonomous vehicles based on their complexity, we put into the centre of our work the simulation of fuel consumption and its prediction for autonomous vehicles. As the demand for automotive especially for autonomous and connected vehicle simulating environments are increasing there are more and more available tools. In our project we had the opportunity to compare three of them that are broadly utilized in the automotive industry. Our aim is set up a model for energy consumption and recharging necessity of plug in hybrid self-driving vehicles and for that the best environment was chosen. Modeling and simulation the fuel economy consumption and refueling of autonomous vehicles is an enabler to have a clear picture about their effect on the environment. Three modelling and simulation environments [13–15] was reviewed and based on its capacities IPG Carmaker was chosen. It provides an environment, where it is possible accurately model real-world test scenarios in a virtual world with the entire surrounding environment. IPG Carmaker has real-time capable models for vehicles, different road types, drivers and traffic situations. It is an open integration and test platform and can be applied throughout the entire development process. It has features to model- to software- to hardware- to vehicle-in-the-loop tests. Program environment is able to test execution with various vehicle state variables, as velocity, engine rotation speed, traveled distance, ore ach wheels lateral acceleration, can be calculated, recorded and displayed in diagrams. IPG Carmaker is a multi-modal tool for autonomous vehicle modelling and simulation, and according to its manual [14] and our trial it has special feature to model fuel consumption and with external extension emission modeling is available as well.

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As summary of the literature overview it can be concluded that autonomous and connected vehicles will have an important role in the future of the road mobility. As future of propulsion technology is unclear yet, our approach is to focus on plug in hybrid technology while it cover the two strongest applicant: electric vehicle and internal combustion engine as well.

3 Fuel Consumption Model Our autonomous plug-in-hybrid vehicle fuel consumption and refueling prediction model aiming to able to calculate the expected energy consumption of the vehicle based on on-board and environmental influencers and with the help of destination and refueling options data optimize the route of the vehicle. In our previous work [1, 2] fuel consumption related parameters were summarized. As next step a graph model was set up. Basis of our approach is to use the shortest distance model method. To define this N  N matrix that contains all potential points (towns, recharging points, staring point, destination etc.) that can be starting or finishing or intermediary point of the route. The matrix contains the distances of all points. The unavailable points that are out of the vehicles actual range have the distance of ∞. With the help of the graph network of filling points (peaks) and routes (lines) cab be represented, to which points and capacities can be assigned as well as time and cost items for each lines. Since route planning and optimization are the basis of our research, the graph will be a weighted, directed graph (see Fig. 1).

Fig. 1. Graph will be a weighted, directed graph [16].

Route graph is generated based on geo-informatic systems data. Peaks of the graph are the potential points and the lines are the potential routes. Routes can be divided into subparts if these subparts have special effect on fuel consumption as relief or quality of road surface. This process helps to improve the reliability of the method. Weight parameters of the graph are determined based on the previous work. Before running the optimization the main optimization parameter or the sequence of the parameters should be decided. Decision parameters can be environmental (minimize the emission), lowest fuel consumption, fastest route, minimal cost route. In case of electric vehicles and plug in hybrid vehicles but as well in case of internal combustion vehicles the distance of refueling or recharging points, its occupancy ratio,

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expected time of recharging and expected time of waiting to be recharged, inventory are important parameters of the optimization. In time and cost optimized cases it can easily happen that electric recharging is proposed to done only parallel to traditional refueling. Complicates the search for optimum that while conventional fuel level in the vehicle has a decreasing tendency between two refueling, the status of the battery can be various based on its utilization type. This phenomena results more complicated range and refueling prediction.

4 Simulation of Hybrid Vehicle Fuel Consumption As first step of testing the graph based fuel consumption prediction model a route was chosen. Main aim of this step was to test the chosen simulating environment with creating a specified route and on that run a simulation of a PHEV. A circle road track was modelled with two different speed limits: the external curve has the limit of 90 km/h and internal part has the limit of 50 km/h. When selecting the modeled road section, it was an important aspect to be expandable with intersections for later simulation and validation of decision situations. In addition, we have been looking for a road section that can be used exclusively during the tests, and is allowed to test autonomous vehicles and even autonomous vehicles in the development phase. A further aim was to make the road section suitable for carrying out the comparative fuel tests of self-driving vehicles in the future. The map of the track is to see in Fig. 2.

Fig. 2. Figure Test track for simulation.

Maneuver of the test vehicle starts from a chosen null point, and it was set like to aiming to reach speed limit (high speed zone 90 km/h and low speed zone 50 km/h). Tested vehicle was a plug-in hybrid test vehicle, which has a parallel hybrid drivetrain (which means that the two axles are drove separately). It contains combined the elements of traditional internal combustion engine equipped and electric vehicles. Main goal of the simulation was to test simulations environment with a basic dataset if it is able to model fuel and energy consumption. IPG Control built-in extension of IPG Carmaker is the right tool to follow vehicle on-board combined energy balance.

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The simulation is run to see the fuel consumption of the vehicle. With this built-in tool, the user can show figures about the simulation. In this case, x axis is the driven distance [m] and y is the fuel consumption (absolute fuel consumption, actual fuel consumption, absolute electric consumption and actual electric consumption). Results are presented with and without extra on board consumer on Fig. 3.

Fig. 3. Results of fuel and energy consumption simulation.

Figure 3 shows that simulations with and without extra on-board consumers have a very similar energy consumption profile. In this model 1,500 W heating energy consumption was modelled. Expected fuel consumption increase was 7.15% based on vehicle measurements and overall result of the simulations was 7.1%. Main difference between the two presented test scenarios is to see around 1,200 m, where the increased electric consumption was recharged by an extra utilization of the internal combustion engine. It resulted the difference in absolute fuel consumption with same amount of used electric energy.

5 Conclusion In our research paper it is highlighted the importance of fuel consumption prediction of autonomous plug-in-hybrid vehicles, as these vehicles containing all state of the art propulsion technologies that will play important role in the mobility of the next decades. We overviewed three commonly used model- and simulation environment and based on their potential utilization one was chosen. In this test environment a basic set up was built up to do basic test about its potential utilization and validate is with tests. Our test resulted that modelled fuel consumption method could be tested in simulation for hybrid autonomous vehicles in the future. It is an important outcome, while

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autonomous vehicles testing will be more and more done in virtual test environment. Our next research step is to extend the reality based test environment with potential decision points and improve the testing with more factors that are influencing the fuel consumption of the vehicle. Acknowledgements. The project has been supported by the European Union, co-financed by the European Social Fund. EFOP-3.6.2-16-2017-00002. The research was supported by the Hungarian Government and co-financed by the European Social Fund through the project “Talent management in autonomous vehicle control technologies” (EFOP-3.6.3-VEKOP-16-201700001).

References 1. Zöldy, M., Zsombók, I.: Modelling fuel consumption and refuelling of autonomous vehicles.. In: Horizons of Railway Transport 2018, MATEC Web of Conferences, vol. 235, p. 00037 (2018). https://doi.org/10.1051/matecconf/2018235000 2. Zöldy, M., Zsombók, I.: Influence of external environmental factors on range estimation of autonomous hybrid vehicles. CzOTO 1(1) (2018) 3. Geiger, A., Holló, A., Thernesz, A., Durgo, R., Czibor, S., Bartha, L, Gergó, P.: Chemically Stabilized Rubber Bitumen, EEC, Istanbul, Turkey, pp. 1–8 (2012). ISBN/EAN 978-90802884-0-9 4. Torok, A., Torok, A., Heinitz, F.: Usage of production functions in the comparative analysis of transport related fuel consumption. Transp. Telecommun. J. 15(4), 292–298 (2014). https://doi.org/10.2478/ttj-2014-0025 5. Szalay, Z., Tettamanti, T., Esztergár-Kiss, D., Varga, I., Bartolini, C.: Development of a test track for driverless cars: vehicle design, track configuration, and liability considerations. Periodica Polytechnica Transp. Eng. 46, 29–35 (2017). https://doi.org/10.3311/PPtr.10753 6. Taiebat, M., Brown, A.L., Safford, R.H., Qu, V.S., Xu, M.: A review on energy, environmental, and sustainability implications of connected and automated vehicles. Environ. Sci. Technol. 52, 11449–11465 (2018). https://doi.org/10.1021/acs.est.8b00127 7. Bhavsar, P., He, Y., Chowdhury, M., Fries, R., Shealy, A.: Energy consumption reduction strategies for plug-in hybrid electric vehicles with connected vehicle technology in urban areas. Transp. Res. Rec. J. Transp. Res. Board 2424, 29–38 (2014). https://doi.org/10.3141/ 2424-04 8. Mersky, A.C., Samaras, C.: Fuel economy testing of autonomous vehicles. Transp. Res. Part C (2016). https://doi.org/10.1016/j.trc.2016.01.001 9. Wu, G., Boriboonsomsin, K., Xia, H., Barth, M.: Supplementary benefits from partial vehicle automation in an ecoapproach and departure application at signalized intersections. Transp. Res. Rec. J. Transp. Res. Board 2424, 66–75 (2014). https://doi.org/10.3141/2424-08 10. Rajamani, R., Shladover, S.E.: An experimental comparative study of autonomous and cooperative vehicle-follower control systems. Transp. Res. Part C: Emerg. Technol. 9, 15–31 (2001). https://doi.org/10.1016/S0968-090X(00)00021-8 11. Antonya, C., Butnariu, S., Beles, H.: Parameter estimation from motion tracking data. In: Duffy V. (ed.) Digital Human Modeling. Applications in Health, Safety, Ergonomics and Risk Management: Ergonomics and Health, DHM 2015. Lecture Notes in Computer Science, vol. 9185. Springer, Cham (2015)

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12. Feng, Y., Head, K.L., Khoshmagham, S., Zamanipour, M.: A real-time adaptive signal control in a connected vehicle environment. Transp. Res. Part C Emerg. Technol. 55, 460– 473 (2015). http://dx.doi.org/10.1016/j.trc.2015.01.007. Engineering and Applied Sciences Optimization (OPT-i) – Professor Matthew G. Karlaftis Memorial Issue 13. Prescan TASS – Users Manual, © 2018 TASS International Version 8.4.0 14. IPG Carmaker – Users Guide, User’s Guide Version 7.0.1 15. ITD Vires-Format Specification, Rev. 1.4 – DRAFT 16. Tankovtar. https://www.tankonyvtar.hu/hu/tartalom/tamop425/0038_informatika_Geda_ Gabor_Hernyak_Zoltan-Algoritmizalas_es_adatmodellek/ch04.html. Accessed 17 Jan 2019

Justification of Influence of the Form of Nozzle and Active Surface of Bernoulli Gripping Devices on Its Operational Characteristics Volodymyr Savkiv1, Roman Mykhailyshyn1(&), Frantisek Duchon2, and Pavlo Maruschak1 1

Ternopil Ivan Pul’uj National Technical University, Ruska str. 56, 46001 Ternopil, Ukraine [email protected] 2 Slovak University of Technology in Bratislava, Ilkovičova 3, SK 812 19 Bratislava, Slovak Republic [email protected]

Abstract. The advantages of application on production of radial flow gripping devices of industrial robots are justified. The mathematical model for numerical modeling of dynamics of air flow in nozzle of radial flow gripping devices and in radial interval between its active surface and surface of object of manipulation is presented. For this purpose it is used averaging on Reynolds of NavierStokes’s equation of dynamics of viscous gas, SST model of turbulence and c-model of laminar and turbulent transition. Technical requirements to design of radial flow grippers are defined and options of their constructive improvement are offered. The formula for calculation of the minimum diameter of nozzle of radial flow gripper is offered. By the results of numerical modeling in the program Ansys-CFX environment influence of geometrical parameters of nozzle and active surface of radial flow gripping devices on the nature of distribution of pressure in radial interval and its upward force is defined. Keywords: Bernoulli gripping device
Object manipulation
Nozzle
Radial flow
Industrial robot
RANS
SST-model of turbulence

1 Introduction In industrial production for the solution of problems of automation of loading and unloading operations with use of industrial robots, transportation and pickings of objects of production the Bernoulli gripping devices (BGD) [1–6] are widely used. BGD are characterized by high safety in operation and durability of operation due to lack of mobile elements. They have high dynamic characteristics (time of gripping of objects of manipulation is less than 0.5 s) [7]. Due to simplicity of design of BGD, lack of special requirements to material and accuracy of their production - they possess low prime cost. The main difference of BGD from other grippers is the lack of mechanical contact (or the minimum contact piece) with surface of the object of manipulation (OM) that is important during the work from easy deformed, fragile, heated or objects with external coverings, unstable to attrition. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 263–272, 2020. https://doi.org/10.1007/978-3-030-38666-5_28

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Now BGD are widely used in the radio-electronic industry for manipulation of semiconductor plates, solar elements and printed circuit boards [8]. Application of BGD in polygraphy at production and the subsequent use of lithographic printing forms [9] is also known, in the food industry for manipulation of cut meat [10] and vegetable [11] plates, in the textile industry [12]. There is a wide prospects of application of BGD in pharmaceutical industry. It is most of all investigated and introduced on production BGD with cylindrical or circular nozzle and vortex grippers. For the purpose of minimization of energy consumption of Bernoulli gripping device when performing handling operations by authors of the article the method of optimization of gripper orientation in the course of manipulation was developed. The method of optimization of Bernoulli gripping device orientation when performing transport operations on a rectilinear and arc trajectory is provided in the articles [13, 14]. Influence of force of front resistance of Q1, Q2 on the minimum necessary lifting force is investigated in article [15]. The description of experimental installation and the analysis of the received experimental results on application of a method of optimization of Bernoulli gripping device orientation is described in the paper [16]. Gasdynamic analysis of the Bernoulli grippers interaction with the surface of flat objects with displacement of the center of mass carried out in [17, 18]. Also authors in the article [19] deals with the topical issue of reducing energy consumption for transportation of industrial objects. The energy efficiency of the process of objects manipulation with the use of the orientation optimization method while gripping with the help of different methods has been studied. The economic efficiency of the use of the optimal orientation of Bernoulli gripping device while transporting the object of manipulation in comparison to the transportation without reorientation has been proved. Influence of parameters of a gripping system on power expenses of the industrial robot during transportation is investigated in article [20]. However, condition and dynamics of course of gas stream in snivel and in radial interval between the interacting surfaces of BGD and OM [21], methods of increase in lifting ability of these devices due to optimization of their design data are insufficiently studied and demand further research. Therefore the questions concerning justification of parameters of radial flow gripping devices is relevant and expedient, considering expansion of the sphere of their use in productions. In particular BGD surfaces on its operational characteristics are of the practical interest of probe on influence of form of nozzle and active (interacting with object of manipulation). The objective is solved with application of methods of computing hydraulic gas dynamics and information technologies for imitating numerical modeling by the finite element method (FEM). FEM allows to define distributions of pressure, speeds with high precision, to receive lines of current and other parameters of streams.

2 Methodology The principle of work of BGD consists in the following. Compressed air through nozzle 1 of the Bernoulli gripping device (Fig. 1) via nozzle 2 by radius rn follows into the camera between its face surface and the surface of OM 3. At the same time on rn radius, at hc < rn/2, the stream experiences the biggest narrowing. In the place of the

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biggest narrowing, with excessive pressures of food of gripper by compressed air more than 30 kPa, the stream reaches critical speed, equal to acoustic speed for these conditions. As a result of further increase in the area of radial stream, its supersonic speed grows, and the static pressure upon surface of OM decreases to size smaller than atmospheric. At some distance from the center of nozzle there is hard braking of supersonic stream, to the subsequent its transition in subsonic that is followed by formation of pressure jump. As a result of further of times expansions the speed of subsonic stream falls, and static pressure in spacing slowly increases up to the size of atmospheric pa. Action of depression on surface of OM leads to its levitation. Side offset of OM prevent thrust blocks 4.

Fig. 1. Constructive scheme of BGD.

Operational characteristics of BGD depend on parameters of source of the power and those geometrical parameters influencing formation of air flow in radial interval, in particular rn nozzle radius, external radius of gripper of rg, hc distance from edge of nozzle to OM. The mathematical model of course of air in radial interval between the interacting surfaces of BGD and OM is based on Navier-Stokes’s (Reynolds averaged NavierStokes equations) equations (RANS) average according to Reynolds [22, 23]. Neglecting mass forces the system of the equations will have the following appearance: @q @ðq
Vj Þ þ ¼ 0; @t @xj

ð1Þ

equation of continuity of stream: q

@Vi @Vi @Pji þ q
Vj
¼ ; @t @xj @xj

ð2Þ

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energy equation: q

 @E @E @qj @
þ q
Vj
¼ þ Pji
Vi ; @t @xj @xj @xj

ð3Þ

ideal gas law equation: q¼

pa þ p ; R
T

ð4Þ

where i, j – indexes, accept values 1, 2, 3; q – air density; t – time; x – coordinate; V – vector of speed of the movement of air; p – excessive pressure of air; P – tensor of tension; E – total energy of air; q – the vector of density of heat flux considering transfer of heat due to heat conductivity and diffusion; R – gas constant; T – absolute air temperature. For carrying out modeling the system of the Eqs. (1–4) has to model of turbulence becomes isolated. For the description of turbulence it is chosen, the model of transfer of tension of shift (Shear Stress Transport) (SST) created Mentera [24]. Later SST model of turbulence it is complemented with models of transition [25, 26] that has allowed to predict the provision of laminar and turbulent transition. These models are based on use of intermediate factor c which value in the set point is defined by the relation current of which the turbulent mode by the general time of observation is observed. In article [27] the model of laminar and turbulent transition with the friend the differential equation for size c is offered (c-model): @ðpcÞ @ðpVj cÞ @ þ ¼ Pc  Ec þ @t @xj @xj

   l @c lþ t ; rc @xj

ð5Þ

where Pc , Ec – respectively generative and dissipation members of managing directors of laminar and turbulent transition; l – molecular dynamic viscosity of gas; lt – turbulent dynamic viscosity of gas; rc ¼ 1:0 – model constant. Together with c-model use the modified equations of the SST model:   @ @ @ @k ~ k þ Plim ~ ðqkÞ þ ðqVj kÞ ¼ P  D þ ðl þ r l Þ ; k k t k @t @xj @xj @xj

ð6Þ

  @ @ Pk @ @x ðqxÞ þ ðqVj xÞ ¼ a  Dx þ Cdx þ ðl þ rx lt Þ ; @t @xj @xj @xj vt

ð7Þ

where k – kinetic turbulent energy; x – the specific speed of dissipation of kinetic energy of turbulence; Pk , Dk – original generation and dissipation of the SST model; – the additional part, which provides the correct gain of turbulent viscosity in Plim k transitional area at very low level of turbulent viscosity of the running stream; vt – turbulent kinematic viscosity of gas; rk , a, a1 – empirical constants of model.

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3 Results and Discussions Power and account characteristics of radial flow gripper generally depend on design data of nozzle and active surface and also on pneumo magistral parameters. The main requirement to rational design of radial flow grippers is existence of smooth active surface provides smooth expansion of air flow and has no performances which would interfere stream [21, 28]. Providing smooth entrance and exit from nozzle reduces losses of energy of air flow and reduces jog force in zone opposite to nozzle. The active surface of gripper can be flat, conical, spherical, toroidal or consist of combination of these elementary surfaces. Rational designs of radial flow grippers, which provide maximum sucking force, are given in Fig. 2.

Fig. 2. Schemes of radial flow grippers with various combinations of forms snuffled also active surface: (a) cylindrical nozzle and flat surface; (b) the rounded-off nozzle and flat surface; (c) the rounded-off nozzle and flat surface from ladders - which; (d) the rounded-off nozzle and flat and toroidal surface.

At the expense of nozzle curve (Fig. 2, b) and special blading of active surface radial flow gripping devices (Fig. 2, d, c) losses of energy of stream at entrance to radial play decrease and by viscous friction in this interval, big degree expansion of air flow is reached. It allows to use more effectively energy of air flow and to increase lifting ability of radial flow grippers at contactless manipulation of flat objects.

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For reduction of size of repellent force at the time of gripper of object of manipulation (h0 > 1 mm) it is expedient that the stream when passing through nozzle was narrowed with the subsequent expansion on entrance to radial play between active surface of BGD and flat object. Such geometry of stream is provided by the BGD design with the rounded-off nozzle (Fig. 2, b). Diameter of the smallest section of the rounded-off nozzle should be chosen from condition that the area of this section pd02 =4 was on 30–50% more than the area of critical section S ¼ 2prn hc d0 ¼

pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ð10:4. . .12Þrn hc :

ð8Þ

For definition of distribution of pressure upon surfaces of object of manipulation numerical modeling of the BGD with such geometrical parameters is carried out: external BGD radius rg = 30 mm, nozzle radius rn = 3 mm, diameter of the smallest section of nozzle of d0 = 2.5 mm, height of radial interval of hc = 0.2 mm, width round ache facets d = 0.3 mm, radius r1 =12 mm. Numerical modeling was carried out in the environment of computing hydro-gas dynamics by ANSYS-CFX with use of SST of c-model of turbulence. For carrying out calculations means this program environments in settlement area have constructed unstructured final and differential grid (Fig. 3).

Fig. 3. Settlement grid of final elements of air flow.

The total number of knots in settlement area makes 3.2 million. Knots of grid are united in volume elements (tetrahedrons and prisms). Total number of volume elements of grid it is equal to 7 million. The total number of tetrahedrons makes 3.2 million. As material is used air as ideal gas from libraries of the program. Boundary conditions for model of air flow are presented on Fig. 4. By the results of the executed calculations with use decisive the sonicTurbFoam module (for turbulent streams of the compressed gases moving with sound and supersonic speeds) schedules of distribution of pressure upon surfaces of OM have been constructed (Fig. 5) and schedules of change of average flow rate in radial play (Fig. 6).

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Fig. 4. Extreme conditions for air flow model.

4,00,000 3,50,000 3,00,000

Pressure (Pa)

2,50,000 2,00,000 1,50,000 1,00,000 50,000 0 -50,000

0

2

4

6

8

10 12 14 16 18 20 22 24 26 28 30

-1,00,000

r (mm) 1

2

3

4

5

Fig. 5. Schedules of distribution of pressure upon surfaces of object of manipulation for various options of design of BGD: 1 – the rounded-off nozzle and flat and toroidal surface; 2 – the rounded-off nozzle and flat surface; 3 – cylindrical nozzle and flat surface; 4 – the rounded-off nozzle and flat surface from ladders - which; 5 – (theoretical) cylindrical nozzle and flat surface.

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600 500

V (m/s)

400 300 200 100 0 0

5

10

15 r (mm)

Fig. 2,d

20

25

30

Fig. 2,a

Fig. 6. Schedules of change of average flow rate in radial play.

Apparently from Fig. 5, when using in design of BGD of the rounded-off nozzle the excessive pressure in zone opposite to nozzle decreases. In comparison with the BGD with flat active surface, when using combination flat and toroid-ache surfaceswidth of supersonic zone of depression (Fig. 6) grows. At the same time in subsonic zone instead of excessive pressure (in case of flat surface) to affect surface of OM depression (in case of combination of flat and toroidal surface). It in general leads to increase in lifting force gripper of object of manipulation which is determined by integration of distribution of absolute pressure of pr on flat surface of the last: Zrg ðpa  pr Þrdr:

F ¼ 2p

ð9Þ

0

As a result of integration of data of distribution of pressure upon surfaces of object of manipulation it is established that gain of upward force for improved versions of design of the BGD (Fig. 2c, d) increases on 50…70% in comparison with basic design (Fig. 2a). At the same time data of computational modeling show gain of a consumption of compressed air when using of the rounded-off nozzle only on 6–9%.

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4 Conclusions The mathematical model for numerical modeling of dynamics of air flow in the nozzle of radial flow gripping devices and in radial interval between its active surface and surface of object of manipulation is presented. Options of constructive improvement of radial flow gripping devices of industrial robots are offered. On the basis of probes it is established that rounded nozzles radial flow gripping devices it is expedient to choose diameter of the smallest section so that the area of this section was on 30–50% more than the area of critical section. It is established that when using in design of the radial flow gripper of the roundedoff nozzle – the excessive pressure on surface of object of manipulation in zone opposite to nozzle decreases. If the work face of radial flow gripper is consecutive combination of flat and toroidal surfaces – the size of supersonic zone of depression increases and depression size grows in subsonic zone. Such constructive improvements allow to increase power characteristics of radial flow grippers on 50…70%. At the same time the consumption of compressed air increases only on 6–9%.

References 1. Li, X., Kagawa, T.: Development of a new noncontact gripper using swirl vanes. Robot. Comput. Integr. Manuf. 29(1), 63–70 (2013) 2. Li, X., Kagawa, T.: Theoretical and experimental study of factors affecting the suction force of a bernoulli gripper. J. Eng. Mech. 140(9), 04014066 (2014) 3. Festo AG & Co, Bernoulli gripper OGGB. https://www.festo.com/net/sv_se/SupportPortal/ default.aspx?cat=4564 4. SMC. http://www.smcworld.com/products/en/vacuum/s.do?ca_id=1036 5. Aventics. Non-contact transport system. https://www.aventics.com/en/products/pneumaticproducts/vacuum-technology/non-contact-transport-system/ 6. Schmalz, J., Schmalz, J.: Floating Suction Cups SBS > Special Grippers. https://www. schmalz.com/en/vacuum-technology-for-automation/vacuum-components/special-grippers/ floating-suction-cups/floating-suction-cups-sbs 7. Ozcelik, B., Erzincanli, F., Findik, F.: Evaluation of handling results of various materials using a non-contact end-effector. Ind. Robot Int. J. 30(4), 363–369 (2003) 8. Stühm, K., Tornow, A., Schmitt, J., Grunau, L., Dietrich, F., Dröder, K.: A novel gripper for battery electrodes based on the Bernoulli-principle with integrated exhaust air compensation. Procedia CIRP 23, 161–164 (2014) 9. Contactless handling of objects [Text]: pat. 6601888 United States: Int. Cl.7: B25J 15/06 Lon McIlwraith, Andrew Christie; Assignee: Creo Inc., Burnaby (CA) – Appl. No.: 09/810408; filed 19.03.2001; date of patent 05.08.2003; priority 19.09.2002, US 2002/0130524 A1 10. Erzincanli, F., Sharp, J.M., Erhal, S.: Design and operational considerations of a non-contact robotic handling system for non-rigid materials. Int. J. Mach. Tools Manuf 38(4), 353–361 (1998) 11. Davis, S., Gray, J.O., Caldwell, G.: An end effector based on the Bernoulli principle for handling sliced fruit and vegetables. J. Robot. Comput. Integr. Manuf. 24(2), 249–257 (2008)

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12. Ozcelik, B., Erzincanli, F.: A non-contact end-effector for the handling of garments. Robotica 20(4), 447–450 (2002) 13. Savkiv, V., Mykhailyshyn, R., Fendo, O., Mykhailyshyn, M.: Orientation modeling of bernoulli gripper device with off-centered masses of the manipulating object. Procedia Eng. 187, 264–271 (2017) 14. Savkiv, V., Mykhailyshyn, R., Duchon, F., Mikhailishin, M.: Modeling of Bernoulli gripping device orientation when manipulating objects along the arc. Int. J. Adv. Rob. Syst. 15(2), 1729881418762670 (2018) 15. Mykhailyshyn, R., Savkiv, V., Duchon, F., Koloskov, V., Diahovchenko, I.: Analysis of frontal resistance force influence during manipulation of dimensional objects. In: 2018 IEEE 3rd International Conference on Intelligent Energy and Power Systems (IEPS), pp. 301–305 (2018) 16. Mykhailyshyn, R., Savkiv, V., Mikhalishin, M., Duchon, F.: Experimental research of the manipulatiom process by the objects using bernoulli gripping devices. In: Young Scientists Forum on Applied Physics and Engineering, pp. 8–11 (2017) 17. Mykhailyshyn, R., Savkiv, V., Duchon, F., Maruschak, P., Prentkovskis, O.: Substantiation of bernoulli grippers parameters at non-contact transportation of objects with a displaced center of mass. In: Transport Means - Proceedings of the International Conference, pp. 1370–1375 (2018) 18. Savkiv, V., Mykhailyshyn, R., Duchon, F., Fendo, O.: Justification of design and parameters of Bernoulli–vacuum gripping device. Int. J. Adv. Rob. Syst. 14(6), 1729881417741740 (2017) 19. Savkiv, V., Mykhailyshyn, R., Duchon, F., Mikhalishin, M.: Energy efficiency analysis of the manipulation process by the industrial objects with the use of Bernoulli gripping devices. J. Electr. Eng. 68(6), 496–502 (2017) 20. Mykhailyshyn, R., Savkiv, V., Duchon, F., Koloskov, V., Diahovchenko, I.: Investigation of the energy consumption on performance of handling operations taking into account parameters of the grasping system. In: 2018 IEEE 3rd International Conference on Intelligent Energy and Power Systems (IEPS), pp. 295–300 (2018) 21. Wagner, M., Chen, X., Nayyerloo, M., Wang, W., Chase, J.G.: A novel wall climbing robot based on Bernoulli effect. In: 2008 IEEE/ASME International Conference on Mechtronic and Embedded Systems and Applications, pp. 210–215 (2008) 22. Snegiryov, A.Y.: High-performance computing in technical physics. Numerical Simulation of Turbulent Flows, S. Petersburg, Polytechnic University Publ. (2009) 23. Garbaruk, A.V.: Modern approaches to modeling turbulence. St. Petersburg, Polytechnic University Publ. (2016) 24. Menter, F.R.: Two-equation eddy-viscosity turbulence models for engineering applications. AIAA J. 32(8), 1598–1605 (1994) 25. Menter, F.R., Esch, T., Kubacki, S.: Transition modelling based on local variables. In: Engineering Turbulence Modelling and Experiments, pp. 555–564 (2002) 26. Menter, F.R., Langtry, R.B., Vӧlker, S.: Transition modelling for general purpose CFD codes. J. Flow Turbul. Combust. 77, 277–303 (2006) 27. Menter, F.R., Smirnov, P.E., Liu, T., Avancha, R.: A one-equation local correlation-based transition model. Flow Turbul. Combust. 95(4), 583–619 (2015). https://doi.org/10.1007/ s10494-015-9622-4 28. Savkiv, V., Mykhailyshyn, R., Duchon, F.: Gasdynamic analysis of the Bernoulli grippers interaction with the surface of flat objects with displacement of the center of mass. Vacuum 159, 524–533 (2019)

Evaluation of Intelligent Transportation System in Security Consideration Hakan Basargan1(&), Szalay Zsolt2, and Árpád Török2 1

2

Department of Control for Transportation and Vehicle Systems, Budapest University of Technology and Economics, 1111 Stoczek st. 2, Budapest, Hungary [email protected] Department of Automotive Technologies, Budapest University of Technology and Economics, 1111 Sztoczek st. 6, Budapest, Hungary {zsolt.szalay,arpad.torok}@gjt.bme.hu

Abstract. Intelligent Transportation System has been the driving forces to enable the paradigm of autonomous vehicles, smart roads and Internet of Things (IoT). For the safety and security of the traffic and transportation, stabilization of the technology and system is necessary. In addition to this, security of intelligent transportation system also influences the smart security and safety of vehicles, pedestrians and drivers. Thus, it is one of the most important application for the daily technology. There has been significant study related to security in vehicular network systems for intelligent transportation system usages. In this study, smart road and intelligent transportation system terms were explained. Attacks and threats of intelligent transportation system were evaluated with their security solutions while security objectives and architecture of intelligent transportation system and smart road were examined. During the evaluation, The European Telecommunications Standards Institute security standards were considered. It is possible to deduce that with developed technology, attack and threats level will be much bore pre-cariousness. New threats and attacks have to be investigate and simulate to find the solution for them. Keywords: Security of intelligent transportation system
Smart road security
Attack and threat of intelligent transportation system

1 Introduction Smart road which can be defined as road infrastructure which is integrated with advanced communication and network systems is the main component of the Intelligent Transportation System (ITS). Compose of advanced structural materials, information centrals, communication and perceptive networks, self-adaptation, continuous energy supply and energy systems are smart road [1]. The main idea of smart road is centered on the realization of intelligent capabilities [2]. Compared with a conventional road, a smart road be able to extend its service life like improving service quality, reducing safety risk and increasing its performance [3]. The smart road can interact with external factors using discrimination and perception dynamically [4]. Smart road can by symbol of the future transportation system. The envisioned future transportation system can be © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 273–282, 2020. https://doi.org/10.1007/978-3-030-38666-5_29

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characterized as a “five-zero” system, as zero delays, zero casualties, zero emissions, zero maintenance, and zero failure [4]. ITS covers new generation transportation systems. ITS technologies include stateof-the art wireless, electronic, and automated technologies with a goal to improve surface transportation safety, efficiency, and convenience. Collectively, these technologies have the potential to integrate vehicles (public transit, trucks, and personal vehicles); system users; and infrastructure (roads and public transit) [5] (Fig. 1).

Fig. 1. Concept of intelligent transportation system [5].

The technical basis of ITS is the implementation of information and control technologies in transport system operations. These technologies include communication, automated control and computer hardware and software, and adaptation of these technologies to transport requires knowledge of many engineering fields, such as civil, electrical, mechanical, industrial and related disciplines [6]. There are many impact of intelligent transportation systems. Travel time reliability improvements, improved control over travel choices, environmental benefits due to smoother traffic flow, privacy compromise due to data/surveillance nature of some ITS applications, higher risk of implementation due to high technological content and hence higher uncertainty attached to impact predictions [7].

2 Objectives of Smart Road Possible to classify objective of smart roads as security and safety, connectivity, information and comfort. Number of traffic accident can be reduced because of provided real time information. Vehicle and driver can be informed real time about traffic situation and behavior of other vehicles. Safety of pedestrian also is ensured by smart road. Connectivity is the most important objective of smart roads. It provides the communication between vehicles, infrastructures and pedestrians. Information is generated; and provided by connectivity, as a result comfort and security and safety are occurred (Fig. 2).

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Smart Road

Security and safety

Comfort

InformaƟon

ConnecƟvity

Fig. 2. Objectives of smart road.

Comfort which is consist of smart roads by using connectivity provides high level journey for passengers, drivers and pedestrians. It is a very important parameter for user satisfaction. Today, drivers do not want to give full attention to vehicle use. The drive parameter can now be eliminated by making the vehicles more intelligent and integrating these smart vehicles into smart roads. 2.1

Performance Components

For performing smart road application, three performance components are necessary [8]. These components work together with exact order as data collection, data analysis and data transfer (Fig. 3).

Data collecƟon

Data analysis

Data transfer

Fig. 3. Performance components of smart road.

Data collection components collect all monitorable data from transportation system for the traffic situation further analysis. Generally, inductive loop detectors which is electro-mechanic detection system that uses a magnet integrated vehicle or alternating current to induce an electric current in nearby wire [9] and pneumatic tubes which can detect the passing of the vehicle with pressure change of the tubes [10] have been used to gather traffic information like traffic volume, traffic density and spot speed.

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Recently implementation cost and traffic impact during installation make them unpopular. Nowadays, due to technological development especially on sensing and imaging; usage of high definition cameras [11] and radio frequency identification (RFID) systems [12] are increasingly preferred for traffic data collection. High definition cameras can be installed different location of road and take photo and video for processing them with image processing technology for the collecting traffic data such as speed, traffic flow, vehicle types etc. [13]. RFID systems are used to for the road payment [14], collecting traffic data and vehicle localization [15]. At the same time; smart phone, blue-tooth technology, wireless technology and global positioning system (GPS) also provide collected traffic data for the analysis. Data analysis components of smart road provide several information, management and control measures with using the collected traffic data from data collection components. Generally, pre-defined and pre-calibrated models have been adopted for evaluating traffic conditions and providing involved response. Because of new sources of data which was introduced, these models have been extended to the using the new data to improve accuracy and evaluations detail. Data transfer components of smart road support communication between collected and analyzed data and operation center to evaluate and disseminate the data to passengers, drivers, pedestrians, vehicles and infrastructures. Data can be transferred by using wires, optical wires or wireless network such as 3G, 4G, 5G and WIFI with cloud platform.

3 Architecture It is important to evaluate framework of smart road which is the most important element of ITS (see Fig. 4). The framework of smart road has 5 interrelatedness parts. Infrastructure-based data which is provided by infrastructure sensors, vehicle-based data which is provided by vehicle sensors, road server, traffic service provider and wireless communication. Infrastructure and vehicle sensors collect data of infrastructure and vehicle. These data is forwarded by with wireless communication which can be proprietarily described as infrastructure to infrastructure (I2I) and vehicle to infrastructure (V2I) to the server which is located roadside. Road-side server keeps the all these data and share with traffic service provider. Information of traffic service can be provided real-time to vehicle, infrastructure, driver and passenger. ITS architectures are different forms and levels, ranging from specific structures like layout of communication system or individual ITS element design to high level concepts representing underlying framework. Traffic data collection, traffic management and control, road surface condition monitoring and communication networking are fields concerning traffic and infrastructure are addressed by the overall approach of ITS. There are many solution to generate required performance such as driver information, safety control, emergency response, infrastructure protection and vehicle probes. Architecture of smart road is shown with different layers as Space layer, road infrastructure layer, road surface monitoring layer, management and control systems and traffic, vehicle and user layer (see Fig. 5) [16].

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Fig. 4. Framework of smart road.

Fig. 5. Architecture of ITS [16].

Space and airborne layer include intelligent communication and monitoring systems such as localization elements, monitoring elements, communication elements and mapping elements. GPS and Galileo positioning systems are used for the localization and positioning. Satellite and airborne cameras are used for monitoring and digital maps or other mapping systems are used for the mapping. Traffic, vehicle and user layer include passengers, vehicles and other all traffic parts. Vehicle sensors and systems, vehicles, intelligent vehicles, autonomous vehicles, are in this layer and mostly use space layer, road infrastructure layer and management & control system layer.

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The vehicles, pedestrians and passengers are in this layer to use intelligent road layer for the travel from one to other point. All this interactions are performed in road infrastructure layer. This layer connect with all of other layers (mostly 2 way connection). Road surface monitoring layer include all sensors which are connected to the road surface such as surface sensors, friction sensors, weather sensors and environment sensors. This layer provide and receive information from vehicles. Management & control system later include traffic control center and pavement managing system. Traffic control process are performed in this layer. It is possible to evaluate security architecture according to the study of Hamida classified the ITS security system architectures in three category as Public Key Infrastructure (PKI) based, Crypto based and ID based security architectures [17]. PKI-based security architecture depends on decryption and encryption algorithms to unsure security service like certificate generation, revocation and renewal, issuing and checking. Crypto-based security architecture based on asymmetric and symmetric algorithms to ensure security services. ITS security scheme which provide privacy, integrity and certificated public key cryptography scheme. ID-based security architecture may be adopted, for the purpose of cancel the general of CRL and PKI based approaches. Goal of ID-based security method is to guarantee privacy of ID. Main point of this method is avoiding in generating exact algorithm for pseudonyms based on an ID with firm confirmation [17].

4 Intelligent Transportation System Security Objectives According to European Telecommunications Standards Institute (ETSI) TR 102 893 V1.1.1 standards [18] there are 5 objectives which are confidentiality, authenticity, integrity, availability and accountability for ITS and each of them have functional security requirements. 4.1

Confidentiality

Confidentiality is the state of keeping or being kept secret or private. Information sent or received to an ITS user must not be accessed by unauthorized persons. As requirements, ITS system should provide a means of assign exact information as limited, the limited information should be encrypted, in transmitting process to limited in-formation to another user, ITS user needs to authenticate itself to recipient and if the user receives limited information, it is need to authenticate from sender. The information which held within the ITS-S needs to be protected from unauthorized access. As requirements, ITS needs to permit just authorized ITS applications to access security parameter information and just authorized ITS users must be permitted to access limited information. Information about identity and service capacities shouldn’t be revealed to any other unauthorized users. Management information which sent to or from an ITS needs to be protected from unauthorized. As functional security requirements, management information needs to be accepted only from an authorized source, transmitted management information need to be restrict to access to authorized ITS users and just authorized ITS users need to have important permit as installing

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management information. Management information needs to be protected from unauthorized access; stored management information such as software updates and service profile data need to be restricted to access to authorized ITS users. It should not be possible for an unauthorized party to deduce the location or identity of an ITS user by analyzing communications traffic flows to and from the ITS user’s vehicle; the means to identity information and protect location during transmission need to be have and persistent user identity needs to be included with data of location send to limited multicast address [18]. 4.2

Integrity

The information which is located in ITS needs to be protected from unauthorized deletion and modification; only authorized ITS users and applications need to be permitted to modify or and delete service profile information. The information which sent or received needs to protected against malicious or unauthorized or manipulation during transmission; It needs to implement one or more methods for preventing the manipulation or modification of data which transmits or receives. Management information which performed in ITS need to be protected from unauthorized deletion and modification. Management information which sent to or from an ITS need to be protected against malicious or unauthorized modification or manipulation during transmission [18]. 4.3

Availability, Accountability and Authenticity

For availability, accessing and operating of ITS services by authorized users need not be forestalled by malevolent activity within the ITS environment; the denial of service attack patterns needs to be detected easily. Objective of accountability; The changes about security parameters and applications need to be possible to audit such as additions, deletions and updates; all request for the changes to ITS application and security parameter information need to be recorded [18]. According to authenticity; It should not be possible for an unauthorized user to pose as an ITS-S when communicating with another ITS-S; just authorized ITS-S need to be accessed to emergency vehicle services, ITS message need to be sent in case of suitability authorized, the message need to be sent only if authorized if suitably authorized and the messages which are received from unauthorized source need to be rejected. Receiving and processing management and configuration information from unauthorized user need not to be possible. Restricted ITS services should be available only to authorized users of the ITS; Only authorized ITS users need to be transmit the messages identifying the vehicle as emergency vehicle [18].

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5 Threats and Attacks of Intelligent Transportation System Hamida [17] described main threats, attacks and security solution of ITS. Possible to see main ITS threats and attacks related to availability, authenticity, confidentiality, integrity and non-repudiation (see Fig. 6). At the same time, solution of threats and their attacks are also listed.

Fig. 6. ITS threats, attacks and security solution [17].

Threats to availability of ITS systems consist denial of services (DoS) attacks as a result like having malicious software and high volume spam message. Such attacks might results in ITS station failing to receive, relay, respond to and sending traffic safety message. Methods of attack include deliberately and falsely generating a high volume of false messages, malware which manipulate the receiving or sending capabilities of ITS station and by accident generating a high volume false message. Threats to integrity of ITS consists loss, corruption and manipulation of information. Accessing unauthorized to restricted information is possible with using malware which injected in ITS station. Loss of information might be result of unauthorized access to restricted information. Authenticity is important security problem in ITS as all ITS stations have the capability to receive, replay and send all types of message. Ensuring authenticity of information processed and received by ITS include: protecting of ITS station from attack, exposure of wrong GNSS signals and protection against wrong broadcast messages.

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Threats to confidentiality of information include illegal collection of data and collection of location information. At the same time, attacker can construct a profile of ITS by observing which services are used regularly, when and where. This traffic analysis may be used to gain information on private emergency vehicles. Accountability can be cause of wormhole and loss of event traceability. Trusted hard-ware which can be modified only by authorized is solution of these threats.

6 Conclusion Introduction of intelligent transportation system and smart road were mentioned while, objectives of smart road and its security component were investigated based on The European Telecommunications Standards Institute standard. Security architecture of smart road and ITS, Threats and attacks of ITS were evaluated and categorized. For future ITS system applications, security measures should be taken at a higher level. After the integration of autonomous vehicles into the infrastructure, security vulnerabilities will increase. Autonomous vehicles should be integrated into intelligent transport systems and should be considered together. Vehicle to everything (V2X) communication type should be considered to analyze new kind of threats and attacks. Therefore, the standards of the future transport system should be different from current one, the autonomous vehicle and the ITS should be considered together. With the development of technology, it will be possible for attackers to turn to different levels and different targets. Thusly, the future attacks should be predicted and analyzed. Simulation and investigation of new threats and attacks are necessary to find the solution for them. Acknowledgement. The research reported in this paper was supported by the Higher Education Excellence Program of the Ministry of Human Capacities in the frame of Artificial Intelligence research area of Budapest University of Technology and Economics (BME FIKP-MI/FM). The project has been supported by the European Union, co-financed by the European Social Fund. EFOP-3.6.2-16-2017-00002.

References 1. Zhao, H., Wu, D.: Definition, function, and framework construction of a smart road. In: Proceedings of 2015 International Symposium on Frontiers of Road and Airport Engineering, pp. 204–218. American Society of Civil Engineer, Shanghai (2015) 2. Zhao, H., Zhu, X., Tu, H., Yang, Z.: Concept and framework of smart pavement. J Tongji Univ. J. Nat. Sci. 45(8), 1131–1135 (2017) 3. Lajnef, N., Chatti, K., Chakrabartty, S., Rhimi, M., Sarkar, P.: Smart pavement monitoring system. Federal Highway Administration, US (2012) 4. Sun, L., Zhao, H., Tu, H., Tian, Y.: The smart road: practice and concept. J. Eng. 4(4), 436– 437 (2018)

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5. Shaheen, S.A., Finson, R.: Intelligent Transportation Systems. Reference Module in Earth Systems and Environmental Sciences. Elsevier Inc., US (2016) 6. Andersen, J., Sutcliffe, S.: Intelligent Transport Systems (ITS) - an overview. IFAC Proc. 33 (18), 99–106 (2000) 7. Newman-Askins, R., Ferreira, L., Bunker, J.: Intelligent transport systems evaluation: from theory to practice. In: Conference of the Australian Road Research Board, pp. 1011–1026 (2003) 8. Sumalee, A., Ho, H.W.: Smarter and more connected: future intelligent transportation system. IATSS Res. 42(2), 67–71 (2018) 9. Liu, H.X., He, X., Recker, W.: Estimation of the time-dependency of values of travel time and its reliability from loop detector data. Transp. Res. Part B: Methodol. 41(4), 448–461 (2007) 10. Nordback, K., Kothuri, S., Phillips, T., Gorecki, C., Figliozzi, M.: Accuracy of bicycle counting with pneumatic tubes in Oregon. Transp. Res. Rec. J. Transp. Res. Board 2593, 8– 17 (2016) 11. Setchell, C., Dagless, E.L.: Vision-based road-traffic monitoring sensor. IEE Proc. Vis. Image Signal Process. 148(1), 78–84 (2001) 12. Saad, A.A., El Zouka, H. A., Al-Soufi, S.A.: Secure and intelligent road traffic management system based on RFID technology. In: World Symposium on Computer Applications & Research (WSCAR), pp. 41–46. IEEE (2016) 13. Zhang, G., Avery, R., Wang, Y.: Video-based vehicle detection and classification system for real-time traffic data collection using uncalibrated video cameras. Transp. Res. Rec. 1993(1), 138–147 (2007) 14. Blythe, P.: RFID for road tolling, road-use pricing and vehicle access control. In: RFID Technology, vol. 123, pp. 1–8. IET (1999) 15. Hahnel, D., Burgard, W., Fox, D., Fishkin, K.: Mapping and localization with RFID technology. In: IEEE International Conference on Robotics and Automation. ICRA 2004, vol. 1, pp. 1015–1020. IEEE (2004) 16. Mayke, D.: INTRO Project Final Summary Report, Germany (2010) 17. Hamida, E.B., Noura, H., Znaidi, W.: Security of cooperative intelligent transport systems: Standards, threats analysis and cryptographic countermeasures. Electronics 4(3), 380–423 (2015) 18. ETSI TR 102 893 V1.1.1: Technical Report, Intelligent Transport Systems (ITS); Security; Threat, Vulnerability and Risk Analysis (2010)

Application of New Materials During Rehabilitation of Road Structures Using Cold Recycling Technology Kateryna Krayushkina1(&), Tetiana Khimeryk2, Olena Oliynyk2, Liliia Gnatiuk2, and Hanna Novik2 1

2

M.P. Shulgin State Road Research Institute, Derzhdor NDI, Peremohy Ave. 57, Kiev 03113, Ukraine [email protected] National Aviation University, NAU, Komarova Ave, 1, Kiev 01123, Ukraine {khimerik,archiprestig}@ukr.net, [email protected], [email protected]

Abstract. The economic attractiveness of cold recycling technology provides, first of all, the reuse of the existing material on the road for the arrangement of new pavement layers, so there is no need to equip special sites for the storage and disposal of old asphalt concrete. The essence of cold recycling technology which is most commonly used for arranging the subbase in Ukraine is that the defective and destroyed layers of road pavement are reinforced on-site by combined additives of organic and mineral binders. Cold recycling by complexity of works is divided into several types depending on the depth of milling. The choice of a rehabilitation type depends mainly on the general state of the pavement structure state which is determined before the beginning of repair work. In Ukraine, the main focus of R&D in cold recycling technology is the use of new materials such as fiber - basalt or polymer, stabilizing additives, industrial waste - slag of various types of industries or other byproducts. Conducted research has shown that the use of organic and mineral mixtures from an optimal mix design with the introduction of basalt fibers increases the crack resistance and durability of the arranged subbase. Keywords: Rehabilitation
Mineral mixtures
Cold recycling
Basalt fibers
Road construction

1 Introduction Road repair and construction organizations in Ukraine annually perform big scopes of work to eliminate defects and deterioration of highways. Rehabilitation of pavement is carried out by different ways, methods and materials which jointly determine the lifetime, the cost and the quality, i.e. the efficiency of the repairs performed. The main purpose of these works is to ensure safe and continuous traffic of motor vehicles with the given speeds [1]. Traditional repair of non-rigid pavements is carried out by their leveling using asphalt mixture and by the arrangement of an additional reinforcing layer. As a result, © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 283–289, 2020. https://doi.org/10.1007/978-3-030-38666-5_30

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the material of the old layers becomes partly a ballast and a source of reflected cracks in the new pavement. The modern way of repair is a cold recycling of asphalt concrete. Analysis of the method of cold recycling in Ukraine and in other countries showed that regenerating additives such as cement and bituminous emulsion are most often introduced in the milled mixture. It is known that in Russia the complex regenerating additives with the addition of cement are widely used. In Poland there is an experience of using slow-hardening mineral slag binder and viscous bitumen diluted with light hydrocarbon diluents, both separately and in complex. In a number of European countries [9–11], granular slag and fly ashes from the heat plants are used as regenerative additives of which slow-hardening mineral binders are prepared. The activators for them are cement and lime. For hydrolysis and hydration of mineral binders the water is introduced into the mixture. In Ukraine, there is little experience in the use of tar cement binder based on 5 Portland cement of M 500 grade and of high-temperature resin of the viscosity C30 ¼ 57c corresponding to the viscosity of D-1 brand. However, only the mix designs that include fibers are characterized by the highest strength, water resistance and frost resistance, resistance to cracks formation and plastic deformations, that is, they are of high deformation ability. The addition of reinforcing fibers to the mix design of the complex regenerating additive results in the formation of a fibrous structural bond in the mixture and in the reduction of its porosity at compaction which contributes to the formation of a durable framework, improved performance and durability of the placed pavement.

2 Statement of Problem During the recent years in Ukraine, for arranging the non-rigid pavements, the cold recycling method was used on the basis of machines – a recycler, a concrete – water suspension preparation plant and a milling cutter [2]. Usage of the milling cutters allows milling the existing asphalt pavement resulting in the formation of so called asphalt crumbs. The reclaimed mixture designed by the authors is used on the roads of Ukraine and includes asphalt crumb, cement, bituminous emulsion and basalt fiber in the volume of up to 5% of total mass of mixture.

3 Materials and Research The dispersion-reinforced mixture used in the study was obtained on the basis of recycled milled asphalt. The usage of basalt fiber improves the strength characteristics of asphalt mixture based pavements, increases the carrying capacity of pavement layers in 1.2–1.5 times and prolongs their lifetime by 40–50% [3]. The source material for basalt fiber is basalt rock which is a fine-grained, effusive raw material of volcanic origin. Basalt fiber is obtained by melting of basalt stone and

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drawing fiber from the resulting melt. The strength of basalt fiber with the diameter of 12–16 microns is 1,500–2,600 MPa, and the density is of 2.8-3.3 g/cm3 respectively. The material is resistant to acids and alkalis. The optimal fiber length based on its even dispersion conditions in the mixture, is 20–25 mm. The general view of fiber is shown (see Fig. 1).

Fig. 1. Basalt fiber (fiber length is 20–25 mm and diameter is 13–20 mkm).

Concrete mixture was prepared according to the following procedure: PC 400 cement, bitumen emulsion (cationic, of average decomposition) and fiber were added to the mixture of milled asphalt crumb, followed by thorough mixing. After preparing the samples at laboratory, the compaction load within the range from 20 MPa to 40 MPa was applied for approximately 3 min. Schematic representation of the organic-mineral mixture with basalt fiber is shown (see Fig. 2).

Fig. 2. Structure of dispersed-reinforced organic-mineral mixture: 1 – asphalt crumb; 2 – film of cement paste with the inclusion of droplets of emulsion bitumen; 3 – basalt fiber; 4 – grains of asphalt crumb with size less than 2 mm; 5 – air voids.

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4 Results According to the research [4], the application of basalt fiber reduces friction between the grains of asphalt granulate that improves the compaction of the reclaimed mixture, increases the number of inter-granular bonds and reduces the inter-granular voids that increases the density of the mixture and makes it possible to open traffic on the reclaimed layer almost immediately after compaction. When the fiber is added to the organic-mineral mixture, a composite material is formed in which the matrix (binder) is significantly strengthened. Due to this the mixture has high bending strength. It is known that the structure of the reclaimed mixture with the addition of bitumen emulsion (cationic) is formed over a sufficiently long time. The application of basalt fiber accelerates the process of structure formation of such mixtures due to chemical interaction with bitumen droplets during the breakdown of emulsion. Basalt fiber improves the electrostatic bonding of bitumen droplets with the surface of mineral grains and prevents their movement, increases the viscosity of the mixture and provides plastic-free flowing consistency. The grading of the organic-mineral mixture using the bitumen emulsion as a binder and cement and basalt fiber is shown (see Fig. 3) [5]. The sleeve size of the screens are indicated according to the current “SDU 45.2-00018112-061: 2011 in Ukraine. Building materials. Organic-mineral road mixes made from milled pavement materials, manufactured using cold recycling technology”.

Fig. 3. Grain size distribution of the selected organic-mineral mixture.

When analyzing the grading curves (Fig. 3) of the selected organic and mineral mixture, it is evident that the mix design with 4% of cement, bituminous emulsion and 5% of basaltic fibers is characterized by a continuous grading, higher content of

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crushed stone fractions as compared with two other mixtures, and it has a small specific surface area (smaller than in the mix designs with non-continuous grading). As a rule, at the technical stages of placement and compaction, such mixtures are subjected to higher compaction efforts, and the formation of the film bitumen on the grains of the aggregates will occur faster providing higher values of bonding forces between the particles thereby contributing to the average strength of the mixture itself. Physical and mechanical characteristics of the designed organic-mineral mixture with basalt fiber, depending on different degrees of compaction load, are given in Table 1. Table 1. Physical and mechanical parameters of the organic-mineral mixture with basalt fiber. Property

Type and consistency of the binder (4% emulsion and 5% cement) Compaction load, MPa 20 30 40 2.24 2.26 2.39 7.1 6.2 4.8 0.7 0.3

Average density, g/cm3 Water saturation, % by mass Swelling, % by mass Compressive strength, MPa, at the temperature of: 0 °C 7.6 20 °C 3.4 50 °C 1.1 Coefficient of short-term water resistance 0.80 Coefficient of long-term water resistance 0.83

8.3 3.7 1.3 0.82 0.87

8.7 3.9 1.4 0.87 0.89

Analysis of the data indicates that the increase of the compaction load decreases the level of concrete water saturation, increase the average density, and increase the compressive strength and the water resistance coefficient (both, short-term and longterm). The optimal choice of the binder’s quantity of cement, emulsion and basalt fiber was confirmed by determining the dependence of frost resistance coefficient on different quantity of binder, as shown (see Fig. 4). When analyzing the data shown in Fig. 4, it is evident that the mix designs have increased frost resistance. The value of the coefficient of frost resistance for the milled mix design with the introduction of regenerating additives of another type (foamed bitumen, slag cement, stabilizer) is 10–20% as compared with the obtained results (Кмpз = 1–0,78) for cycles 0–50, respectively. This indicates that the selected mix design has sufficient deformability at negative temperatures and will provide crack resistance during the operation during in winter. As it can be seen from the data shown in Fig. 4 [6–8], the organic-mineral mixture including 4% of cement, 5% of bitumen emulsion and 5% of basalt fiber corresponds to the highest values of frost resistance.

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Frost resistance coefficient

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Number of freezing-thawing cycles Fig. 4. Dependence of frost resistance coefficient on different quantity of binder.

5 Conclusions 1. The conducted studies showed that the introduction of basalt fiber (fibers 20– 25 mm in length) into a complex regenerating additive in asphalt concrete crumbs forms fibrous structural bonds in it and allows obtaining the mixture with a stable framework and of increased density (q = 2.39 kg/cm3) and compressive strength (Rsch = 3.9 MPa). 2. The optimum composition of the dispersed-reinforced milled mixture is developed which includes asphalt crumb and complex regenerative additive consisting of Portland cement – 4%, bitumen emulsion – 5% and basalt fiber – 5% of the mass. 3. Due to the formation of chemical bonds in basalt fiber and bituminous emulsion, when mixed, the milled mixture is homogeneous and not subject to plastic deformations which is determined by high physico-mechanical parameters of strength at 50 °C, R50 = 1.4 MPa, water saturation W = 4.8%, that is, it will ensure the reliability of pavement during operation. 4. The optimality of selection of the amount of regenerating additives contributes to higher values of frost resistance coefficient Кмpз = 1–0.78 within the range of freezing-thawing cycles from 0 to 50, respectively, and increased density of the mix design (q = 2.39 kg/cm3). 5. High frost resistance of the reclaimed mixture indicates its deformability under the influence of reduced temperatures and crack resistance during the operation of pavement. Thus, the use of organic-mineral mixtures of milled asphalt with basalt fiber is possible in the upper pavement layers of roads of all categories and significance, as well as ensuring the durability of the layer and the compliance of operating ability of roads with the requirements of traffic.

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According to the results obtained in the research and on roads in operation, the application of basalt fiber provides durability and strength to the layer built with it during the inter-repair time.

References 1. Ilchenko, V.V.: Restoration of pavement using cold milling technology. Collection of Scientific Works (Branch Mechanical Engineering, Construction), no. 18. PoltNTU, Poltava (2006) 2. Draft Guidelines “Road pavement recycling”. PIARC Version (2002) 3. Sasko, M.F.: Cold Recycling, Its Benefits and Prospects, Avtoshlyachovyk Road Worker of Ukraine, no. 2, pp. 37–40(2004) 4. Golovko, S.K.: Cold Recycling - Effective Pavement Rehabilitation Technology, Avtoshlyachovyk (Road Worker) of Ukraine, no. 6, pp. 34–35 (2003) 5. Kostelev, M.P.: Cold Recycling Technology, no. 3. Road technique (2004). http://library. stroit.ru 6. Dolgilevich, Yu.P., Kostelev, M.P., Hakkert, J.: Experience in applying road pavement cold recycling technology in USA. Road Technique, no. 1 (2005). http://library.stroit.ru 7. Malyutin, A.: Technique for cold recycling. Funds, no. 7 (2008). http://www.os1.ru 8. Livitina, V.V., Mamontov, B.P., Mitroshin, A.V.:: Cold recycling – an effective technology for the rehabilitation of asphalt pavement of airfields and highways. Bulletin of Construction Machinery, no. 9 (2007). http://stroy.dbases.ru 9. Turenko, F.P., Filatov, S.F., Shipicin, V.V.: Improving the efficiency and environmental friendliness of road asphalt concrete pavement repair by cold regeneration using slow hardening mineral and organic additives. Omsk Sci. Herald 3(36), 89–91 (2004) 10. Barackh, G.S.: The influence of the structure of asphalt granulobeton on its properties, p. 60 (automobile roads: Inform. Sb./Informautodor: rel. 3) (2001) 11. Prokopets, V.S., Filatov, S.F., Ivanova, T.L., Tarasova, M.V., Pomorova, L.V.: Restoration of asphalt concrete pavements by cold recycling and chemical additives. Bashkir Chem. J. 13 (5), 61–65 (2006)

Research of Dynamic Processes of the System “Track – Vehicle”, When Wheel Is with 0.7 mm Metal Scale Marijonas Bogdevičius1(&) and Rasa Žygienė2 1

Department of Mobile Machinery and Railway Transport, Vilnius Gediminas Technical University, Plytines G. 27, 10105 Vilnius, Lithuania [email protected] 2 Department of Study Program of Motor Transport Electronics, Kaunas University of Applied Engineering Sciences, Tvirtoves al. 35, 50155 Kaunas, Lithuania [email protected]

Abstract. The appearance of a metal scale on the wheel’s surface causes technical and maintenances problems for the rolling stock. Railway standards limit the speed of movement that depends on a certain size of metal scale. Introduced in this article, the results obtained after researching the system “Vehicle – Track”, when the wheel has a metal scale, help to better understand and evaluate the impact of metal scale on wheel on dynamic loads of rail and vehicle and the regularities of their movement. When analysing the interaction between vehicle wheel with a metal scale and rail in the system “Vehicle – Track”, the changes of the kinematic and dynamic parameters of the wheel and rail contact points in time are examined, depending on the height of the 0.7 mm metal scale, when the length of the metal scale is 100 mm and the speed of movement is different. Keywords: Rail-wheel interaction area
Force


Spatial model of metal scale
Contact

1 Introduction In order to avoid dangerous events in railways, when the vehicle wheel has a metal scale, to anticipate the potential impact their shortcomings are a necessity constantly monitor the technical condition, mechanical structures and continuous development more accurate and reliable test methods or systems. The dynamics of railway vehicles have changed over the last decades. Multicriteria decision-making is widely used in all areas. Multicriteria assessment models are presented in the field of transport [1, 2]. Using the [1] multicriterion additive model, it was found that the main parameter of the technical condition of the railway track is the speed of the wagon. The influence of contact forces on the deformation of rolling carload wheels and rails, and the influence of this deformation on the redistribution of the contact stresses is also investigated [3]. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 290–296, 2020. https://doi.org/10.1007/978-3-030-38666-5_31

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Initial surface of vehicle wheel profile is symmetric. However, during exploitation, roughness appears on the surfaces of wheel and rail profiles, due interaction between vehicle wheel and rail, and their different geometrical surfaces. Furthermore, the wheel profile constantly changes. The paper shows results, how the dynamic parameters of a wheel change (forces and other parameters and other parameters), depending on the geometry of metal wheel scale, movement speed and other parameters of the system “Vehicle – Track”. Damages on surfaces of wheel and rail mostly appear due to their interaction and damages are rarely found on initial stages of exploitation, and over time, the damages increase and may cause irreversible consequences.

2 Materials and Methods The Scope of Calculations and Numerical Characteristics of an Adhesive Joint. During exploitation, the metal scale on wheel can take on various forms. This article uses a method for forming a wheel metal scale that allows you to generate a wheel profile with a metal scale if the exact geometry is known. When the geometrical model of metal scale of vehicle wheel, these assumptions and conditions are considered: – The metal scale of the vehicle wheel consists of Nlayer layers. – The profile of metal scale is generated in local coordinate system XCP , YCP , ZCP . – Each centre of metal scale layer can be moved in Z axis by a value of ZCPi0, but ZCP10 = 0. – Geometrical parameters of each metal scale layer (starting from the second layer) are independent values that are selected in such way, that total profile of metal scales would be generated as accurate as possible. The geometry of the wheel with the metal scale on it is shown in Fig. 1.

Fig. 1. The geometry of the wheel with the metal scale.

When interpreting the geometry of a metal case, it is assumed that the number of layers of the calculated metal sheet is Nlayer = 3.

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General function of metal scale profile is described as:   nZPk       ZCP  ZCPk0 _ H ZCP þ bPk_  H ZCP  bPk_ aPk_ 1  bPk_ ð1Þ k¼1 qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi 2 2 2 2  RW  ZCP  RW  bP1 :

fP ðZCP Þ ¼ UðZCP Þ

N layer X

where UðZCP Þ is one of the possible metal scale alignment functions; aPk ; bPk ; bP1 are halves of the layer length of metal scale, where nzc is exponent; RW is nominal wheel radius; H is Heaviside step function. General metal scale function fP ðZCP Þ is used when examining the metal scale profile XCP in ZCP plane, in further calculations. Mathematical Model of System “Vehicle – Track”. When analysing the interaction between elements in system “Vehicle – Track”, these assumptions and conditions are considered: – – – – – – – – – – –

rail deformation in XCP , ZCP plane; initial bending of the rails; interaction between roadbed and rail, as an elastic foundation; possible gap between the sleeper and roadbed; the effect of rail axial forces on rigidity (due to differences in temperature); possible gap between rail and sleeper; bending of rail that is between two sleepers; interaction of soil layers, that is under two adjacent sleepers; length of wheel and rail contact and geometrical unevenness appearing on it; contact zone is examined as linear contact according to XCP coordinate; wheel profile with metal scale.

The system “Vehicle – Track” is examined in vertical plane. System of movement equations of “Vehicle – Track” with the metal scale of wheelset wheel is equal to: ½M f€qg þ ½C fq_ g þ ½Kfqg ¼ fFNL ðq; q_ Þg þ fF ðtÞg

ð2Þ

_ tÞg; fF ðtÞg are mass, damping and stiffness matrices, where ½M; ½C; ½K; fFNL ðq; q; nonlinear generalized force vector and external force vector, respectively; fqg; fq_ g; f€qg are the system generalized displacements, velocities and accelerations vectors, respectively. Each of the computational parameters, given in the mathematical model, are averaged depending on the length of the wheel-rail contact. The computational process continues until the condition of t  Tmax is true. Initial Data of Research. The purpose of the research is to determine the interaction between wheel and rail, show how the wheel and rail movement changes and introduce the impact of geometrical parameters of metal scale on the dynamical loads occurring during the wheel-rail contact, by using the mathematical model of the system “Vehicle – Track”, when the wheel has a metal scale. The system “Vehicle – Track” is analysed,

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when the vehicle wheel has radius R_W = 0.495 m and has a metal scale, is moving on the rail (R-65) at different speeds (V = 60, 80, 100 km/h), when the length of scale is L = 100 mm and the maximum height of scale is hmax ¼ 0:7 mm. The data of system “Vehicle – Track”, used in the calculations is published in previous author’s works [4, 5]. A profile of a vehicle with scaled wheel is described using Fourier transformation, number of harmonics is equal NH = 401. The calculations assume, that average value of friction coefficient between the vehicle wheels in relation to the rail is l = 0.135, obtained from experiments carried out by the authors [4, 5]. Results. The normal force FN increases in the contact zone of wheel with metal scale and rail, when the metal scale is in the contact zone, shown in Fig. 2.

a)

b)

c) Fig. 2. The normal force FN, when height of vehicle wheel scale is 0.7 mm and when the vehicle is moving at the different speed, at time interval from 1.0 s to 1.7 s: (a) 100 km/h; (b) 80 km/h; (c) 60 km/h.

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The value of this force depends on the size of the metal scale and the movement speed. When the movement speed of wheel is V = 100 km/h and the maximum height of metal scale is hmax = 0.7 mm, the maximum normal force FN is equal to 328 kN. The friction force Ffric increases in the contact zone of wheel with metal scale and rail, when the metal scale is in the contact zone, shown in Fig. 3.

a)

b) Fig. 3. The normal force Ffric, when height of vehicle wheel scale is 0.7 mm and when the vehicle is moving at the different speed, at time interval from 1.0 s to 1.7 s: (a) 80 km/h; (b) 60 km/h.

When the movement speed of wheel is V = 80 km/h and the maximum height of metal scale is hmax = 0.7 mm, the maximum friction force Ffric is equal to 52.82 kN. The mechanical power of the friction forces NT increases in the contact zone of wheel with metal scale and rail, when the metal scale is in the contact zone, shown in Fig. 4. The value of this force depends on the size of the metal scale and the movement speed. When the movement speed of wheel is V = 60 km/h and the maximum height of metal scale is hmax = 0.7 mm, the maximum normal force NT is equal to 391.45 W.

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a)

b) Fig. 4. The mechanical power of the friction forces NT, when height of vehicle wheel scale is 0.7 mm and when the vehicle is moving at the different speed, at time interval from 1.0 s to 1.7 s: (a) 80 km/h; (b) 60 km/h.

3 Conclusion The mathematical model allows evaluating the rotation of the vehicle wheel about its longitudinal axis Y, in order to evaluate the rotation of the vehicle wheel and determine its slip on the rails. The developed method allows determining the forces and moments occurring in the contact between wheel withy metal scale and rail. It also allows to adjust the loads on wheel bearings, the permissible wagon speed, depending on the geometry of the wheel with metal scale, and determine the heat release in the contact, the speed and size of the wheel and rail wear, the reduction in ride comfort, etc. By using this method, it is possible to create monitoring systems for damaged wheels with metal scales. It is determined, that when the height of metal scale is hmax ¼ 0:7 mm and the length of scale is L ¼ 100 mm, the maximum normal contact forces FN is 328 kN, when the speed of moving wheelset alters V ¼ 100 km/h, static wheel load is 100 kN and average wheel radius is RW ¼ 0:495 m. When the movement speed of wheel is V = 80 km/h, the maximum friction force Ffric is equal to 52.82 kN. When the height of metal scale is hmax ¼ 0:7 mm, the length of scale is L ¼ 100 mm and speed V ¼ 60 km/h, mechanical power of the friction forces NT ¼ 391:45 W. Part of mechanical power turns is converted to heat per unit of time, due to that, the temperature of wheel scale gets higher and the metal scale can be heavily worn.

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References 1. Sivilevičius, H., Maskeliūnaitė, L.: The numerical example for evaluating the criteria describing the quality of the trip by international. E&M Econ. Manag. 2, 73–86 (2014) 2. Turskis, Z., Zavadskas, E.K.: A new fuzzy additive ratio assessment method (ARAS-F). Case study: the analysis of fuzzy multiple criteria in order to select the logistic centers location. Transport 25, 423–432 (2010) 3. Sladkowski, A., Sitarz, M.: Analysis of wheel–rail interaction using FE software. Wear 258 (7–8), 1217–1223 (2005) 4. Bogdevičius, M., Žygienė, R., Bureika, G., Dailydka, S.: An analytical mathematical method for calculation of the dynamic wheel–rail impact force caused by wheel flat. Veh. Syst. Dyn. 54(5), 689–705 (2016) 5. Žygienė, R., Bogdevičius, M., Dabulevičienė, L.: A mathematical model and simulation results of the dynamic system railway vehicle wheel–track with a wheel flat. Sci. Future Lith. Transp. Eng. 6(5), 95–101 (2014)

Dynamic Charging of Electric Buses as a Way to Reduce Investment Risks of Urban Transport System Electrification Mikołaj Bartłomiejczyk1(&)

and Marcin Połom2

1

Faculty of Electrical and Control Engineering, Gdańsk University of Technology, G. Narutowicza 11/12, 80-233 Gdańsk, Poland [email protected] 2 Faculty of Oceanography and Geography, Department of Regional Development Geography, University of Gdansk, J. Bazynskiego 4, 80-309 Gdańsk, Poland [email protected] Abstract. Night charging and fast charging are currently the two most common systems for charging electric buses. Despite the fact that numerous trial installations were started, neither of these two systems has obtained unqualified approval of the users. The alternative is to charge vehicles in motion - dynamic charging which combines the advantages of trolleybus transport and of electric buses. One of the advantages is the reduction of risks associated with the electrification of urban transport. The investment in the construction of the traction network allows you to reduce the costs associated with the purchase and replacement of traction batteries, as well as increase the flexibility of the transport system. The article presents the financial benefits resulting from the use of a dynamic charging system. Keywords: Electric bus
Trolleybus
Traction batteries
Dynamic Charging
In Motion Charging
LCC
Investment risk

1 Introduction Despite the continuous development of electrochemical batteries technology and the multitude of electric buses on offer, it is still not possible to exploit electric buses in urban transport on all-day basis without the necessity of charging them. Therefore it is necessary to build point-to-point contact charging stations or induction charging stations at the terminals. This results in substantial financial outlays connected with the construction of charging stations, and in the necessity to extend the stopping time at the terminals; there are also problems which arise in the situation where the route is changes. The alternative solution is the so-called Dynamic Charging, also called In Motion Charging (IMC). It consists in building an infrastructure allowing for charging vehicles in motion, most often with the use of overhead contact line (Fig. 1) [1–3]. What is more, in the cities where tram network is already exploited, there is a possibility to use the elements of the tram infrastructure when constructing the catenary for the Dynamic Charging system. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 297–308, 2020. https://doi.org/10.1007/978-3-030-38666-5_32

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Fig. 1. The idea of In Motion Charging system (IMC) [© Vossloh Kiepe].

In the dynamic charging system, part of the route is covered with a trolleybus traction network, which allows for the charging of traction batteries during movement (Fig. 2). The vehicles cover the rest of the route, i.e. the part in which there is no contact line, using traction battery power. This allows for the charging of the vehicle without stopping, increasing the flexibility and functionality of the system. In addition, covering a section of the route with a traction network reduces the length of the route to be travelled in battery mode, which in turn allows for a reduction in the capacity of the traction batteries.

Fig. 2. Idea of dynamic charging system (In motion charging).

The construction of a traction network is associated with significant financial outlays and is the most expensive element of dynamic charging system. For this reason, it is advisable to limit its length. The length of sections accompanied by contact line must be sufficient to charge the traction batteries with energy at least equal to the energy necessary to cover the catenary-free section. With currently used vehicles, the minimum degree of coverage with the traction network is at a level of 40–50% [3]. This value can be reduced by increasing charging power to 25%. In the case of a supply

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system of 750 V DC it is possible to decrease this rate to 20% [1–3]. In the case of a reduction in the heating power of the vehicle or use thermal pumps, it is possible to reduce the degree of coverage below 20%. Figure 3 shows an estimation of the minimal coverage rate in function of charging power, based on, the energy consumption for a standard vehicle was assumed to be 3 kWh/km (winter) and, correspondingly, for an articulated vehicle 3.9 kWh/km [1].

Fig. 3. Minimum catenary coverage in function of maximal charging power [1].

2 The Benefits of Dynamic Charging The benefits of using dynamic electric bus charging will be illustrated by an example of line with a length 10 km, which is operated by standard length electrical buses. Maximal energy consumption at the level 3 kWh/km is assumed. There are analyzed 3 alternative systems of line electrification (Fig. 4): – operation by standard electrical bus with one charging station and Terminus 1. The charging power is 400 kW; – operation by dynamic charged battery bus with one 3 km wired section (variant 1); – operation by dynamic charged battery bus with two wired sections: 1 km and 2 km (variant 2). The average charging power of dynamic charging system is 140 kW, the average velocity in wired section is 20 km/h. The minimal charge level is assumpted at 50%. The Fig. 5 presents the graph of battery charge level of analyzed variants. In case of standard battery bus the maximal discharge level is 60 kWh. With a minimal discharging rate 50%, this requires a 120 kWh traction battery. In fist variant of dynamic charged bus the battery is discharged with energy 42 kW, what allows the required battery capacitance to 84 kWh. In the second variant battery is maximally discharged

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with power 15 kWh. As a result of that, the traction battery with capacitance 30 kWh will be enough to fulfill transportation route conditions.

Fig. 4. The scheme of an example of route operated by standard electrical bus and two variants of dynamic charged buses.

Fig. 5. Diagram of battery charge level during operation of route by standard electrical bus and two variants of dynamic charged buses.

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Covering part of transportation route allows to reduce the required traction battery. The capacitance reduction is bigger in case of using more than one wired sections. This allows to alternate work in mode charging - discharging - charging - discharging. Thanks to this, the depth of discharge is significantly reduced. Considering that the price of the battery is 4,000 to 6,000 PLN for 1 kWh of capacity, the use of overhead contact line saves 400,000 PLN on one vehicle. In addition, the dynamic charging system does not require stops for charging the vehicle, therefore the number of vehicles necessary to operate the line is smaller than in the classic electric bus. Stationary charging involves the necessity to stop the vehicle while it is being charged so for charging time vehicle is unavailable for user. Time is money – so we are losing money while vehicle is charged. What is more, it may result in the need to increase the number of vehicles necessary to operate the line. The table presents the exemplary charging times when we operate route 15 km and charging stations are localized at both terminuses (Table 1). Table 1. The comparison of charging time of electric bus with opportunity charging system. Type of vehicle Charging time* 12 m vehicle 9 min 15 m vehicle 10 min 18 m vehicle 12 min 24 m vehicle 16 min *Assumed energy consumption Energy consumption: 2.2 – 2.6 – 3.2 – 4 kWh/km

3 The Elements of Risk in Transportation Systems with Electric Buses Electric buses are a relatively new means of transport, so there is not enough experience in operation. The electric vehicle market is developing very dynamically and it is very difficult to determine trends in changes in the purchase price of electric vehicles in the future. In addition, there is no experience related to the operation of traction batteries with a large capacity. The key factor here is the battery life, which is currently difficult to assess. As a result, there is a high risk associated with the entry into service of this kind of transport. The following main elements of risk can be distinguished: – the risk related to the purchase price of new vehicles, – the risk related to the cost of replacing the battery, – risk related to traffic congestion and its influence on charging process. 3.1

The Risk Related to the Purchase Price of New Vehicles and the Cost of Replacing the Battery

Currently, the cost of the battery can be up to 50% of the vehicle price. Moreover, during the entire lifetime of the vehicle it will be necessary to replace the battery at least once. A decline in battery price can be expected, but the size of the reduction is very

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difficult to assess. What is important, the increase in the development of electromobility and the increase in demand for energy storage can negatively affect the battery prices. What’s more, for example in Poland the increase in interest in electric buses has caused their prices to rise recently. 3.2

The Risk Related to Traffic Congestion and Its Influence on Charging Process

Stationary charging requires an increase in the number of vehicles servicing the transportation line due to the need to provide an adequate time reserve for vehicle charging. This results in an increase in the number of vehicles in service and the number of drivers. This additional cost is difficult to estimate due to the differing ways of organizing driver service in various transport systems, but currently the cost of drivers accounts for up to 50% of all maintenance costs of the transport system. Thus even a slight increase in the number of rolling stock can cause a significant increase in costs. For this reason, this factor can also be treated as a random element. The necessity of stopping the vehicle during the time of charging is of primary importance in the context of traffic disturbances caused by traffic congestion. They cause a delay in the arrival time to the final stop (Fig. 6), which shortens the time left to recharge the vehicle. In the case of stationary charging, this may cause situations where the remaining stop time is too short to charge the vehicle and it becomes necessary to use on the reserve vehicle. An exemplary situation is shown of Fig. 7.

Fig. 6. Exemplary delays of arrival to final stop on bus route.

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Fig. 7. Influence of traffic delays on battery bus operation – during peak hours delays can cause reduction of stopping time, which can be too short for fully charging.

4 Financial Analysis of the IMC System The biggest difference between stationary charged electrical buses and dynamic charged electrical buses from the economic point of view is the cost structures – with the latter having a higher level of fixed costs and a lower level of variable costs. In order to compare the costs of stationary charged buses and dynamic charged buses a financial analysis was done – analysis of costs, including maintenance costs and costs of assets. A financial comparison of stationary charged electric buses and dynamic charged electric buses will be carried out on the basis of a discounted life cycle cost analysis – LCC. It shows total discounted costs (infrastructure and vehicle): NPV ¼ Ci þ

Xn¼T Cop ðnÞ SV  ; n¼1 ð1 þ r Þn ð1 þ r ÞT

ð1Þ

where Ci – initial costs; T – entire period of analysis; n – given time periods (years); i – financial discount rate; Cop (n) – operational costs in a given period n (year); SV – residual value of infrastructure and vehicles after period T of analysis. The purpose of the financial analysis was to find the extreme life cost values for various input values: the purchase price of a new vehicle, the price of battery replacement and the impact of traffic conditions on the charging process. To analyze the varied settings of given input data parameters, the Monte Carlo Statistics modeling method was used. The Monte Carlo method is based on the continuous repetition of a statistical experiment, which performs an analysis of the condition of the object using random input factors. The result is a distribution of probability of the output variable. The simulation model is based on the randomized input data: – price of purchase of the new vehicle, – price of exchange of the battery during lifetime of the vehicle, – additional charging time caused by traffic delays.

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The schematic diagram of testing the impact the parameters on LCC by means of Monte Carlo method has been presented in Fig. 8.

Fig. 8. The scheme of Monte Carlo calculation model.

The investment and operational costs are shown in Table 2. The cost of battery is the most uncertain element influencing the life cycle costs of transportation systems. The actual price of battery storage systems can be estimated at level 1,000 euro/kWh [4]. In 2017 a 25% reduction in battery price was observed. If this trend continues, the price of battery systems may decrease several more times. On the other hand, many experts are of a different opinion [4]. For this reason, the risk analysis assumes a drop in the price of the battery to 25% of the present value in the optimistic variant and maintenance of the current prices in the pessimistic scenario. Due to the lack of experiences in the field of battery systems lifespans, one and two battery changes were assumed during the lifetime of the vehicle (number of battery exchange was also randomized). Another element with a randomly determined value is the purchase price of a new vehicle. The reason for this is the fact that in the currently dynamically changing market of electric vehicles it is very difficult to determine the purchase price of an electric bus. The third factor of random character taken into account in the simulation model was the impact of traffic congestion on the charging process. In the case of static charged electric buses there is a need to ensure a guaranteed charging time at end points. This increases the required number of vehicles and the number of drivers. This charging

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time is influenced by random road congestion conditions and the organization of work by individual transport operators. For this reason, it should also be considered as a random factor. The maximum increase in the number of vehicles due to charging time kcharging can be expressed as: kcharging ¼

2
Tr þ Tcharg 2
Tr þ Tres

ð2Þ

where Tr – driving time in one direction; Tcharg – required charging time; Tres – time of minimal break at final stop. The minimal value of kcharging is 1, which means no need to ensure additional charging time. Charging station is localized on the one terminus. The value of kcharging was randomizing between the value calculated according to (2) formula and 1. The calculations were made with the following additional assumptions: – share of rides in peak hour is set at 25%, which is used to estimate the number of vehicles needed to serve the connection [4], lower share of rides in peak hour means that less vehicles are needed to serve the line, which influences total costs; share of rides in peak hour is defined as relative to the increasing frequency of transportation in peak hours in comparison to average all day frequency; – 3 rush hours per day were assumed; – number of workday equivalents per year is set at 310 [4], which equals 255 workdays and 110 non-workdays, with 50% daily supply of workdays; – rolling stocks reserve at 10%; – two ways of electrification by dynamic charging were compared: variant 1 (DCh ebus 1) and variant 2 (DCh ebus 2) according to Fig. 5. The influence of battery cost reduction is presented in Fig. 9.

Fig. 9. Influence of the battery price reduction on life cycle cost (mln. PLN) with assumption of one exchange of battery and transportation route interval 8 min.

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The calculations were made with an assumption of the same vehicle price for standard electric bus and dynamic charged electric bus 1,800,000 PLN. Figure 10 present life costs analysis and risk value of life costs for 20% coverage rate by catenary and traffic interval 8 min. Calculations were made with assumptions presented in Table 2. The structure of costs is presented on Fig. 11. It should be summed up that the investment in the traction network allows to reduce risk related to operating costs. This benefit is particularly visible in the high frequency of running vehicles. Table 2. The investment and operational cost of electric buses (C – certain cost; U – uncertain cost; HU – highly uncertain cost; S – static charged bus; D – Dynamic charged bus) [4, 5].

Investment costs

Operational costs

Annotation

Type of costs

Applicable for

Value, min. and max. values

Vehicle purchase

U

S, D

Traction substation Overhead catenary Charging station Drivers personal costs Battery exchange costs

C

D

– max. price: actual results of tenders and market Standard analysis electric bus: – min. price: assumption 75% reducing of battery 1,200– price 2,000 k PLN DChar Bus, variant 1: 1,400– 2,200 k PLN DChar Bus, variant 2: 1,300– 2,100 k PLN 1,200 k PLN Actual results of tenders

C

D

C U

S S, D

HU

S, D

U

S, D

C

D

100 k PLN/km

C

S, D

0.5 PLN/kWh

Vehicle maintenance cost Overhead catenary maintenance cost Energy

1,200 k PLN/km 1,200 PLN 3 PLN/km

Actual results of tenders

Standard electric bus: 140–600 k PLN DChar Bus, variant 1: 100–400 k PLN DChar Bus, variant 2: 40–160 k PLN 1.40 PLN/km

– max. price: assumpted price 4 k euro/kWh – min. price assumption 75% reducing of battery price – the calculation were made for two variants: battery exchange one time and twice per vehicle lifetime

Technical analysis

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Fig. 10. Life cost analysis (mln. PLN) with assumption of 20% coverage of transportation route by overhead wires (in case of dynamic charging) and transportation route interval 8 min.

Fig. 11. Analysis of life cost risk (mln PLN) with assumption of 20% coverage of transportation route by overhead wires (in case of dynamic charging) and transportation route interval 8 min.

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5 Conclusions Despite the fact that the number of cities exploiting electric buses in urban transport is increasing, the existing systems are test systems, and there is still no agreement among the users with regard to an optimal and universal solution for electric buses. The issue of charging is one of the biggest problems. On the other hand, trolleybus transport in numerous cities is considered to be outdated. Dynamic charging makes it possible to combine the advantages of trolleybuses and electric buses. The main financial benefits of dynamic charging system are shown on Figs. 10 and 11. By investment in infrastructure (right side of Fig. 11) we can reduce the risks associated with costs of batteries and influence of traffic congestion on charging process (left side of Fig. 11). The battery price is up to 50% of the purchase price of a new vehicle. Taking into account the dynamically changing market of electric vehicles and the battery life which is difficult to determine, the costs associated with the purchase and replacement of batteries are an important source of financial risk. Thanks to covering the route with the traction network it is possible to reduce the size of the battery, and thus reduce the risk associated with their replacement. The high cost of traction network construction is perceived as the main disadvantage of dynamic charging systems. However, it should be noted that it is incomparably smaller than the infrastructure costs for tram lines. What’s more, the trolleybus overhead contact line for dynamic charging systems has a simpler structure than the classic trolleybus network, because there is no need to build crossing. This significantly reduces the price and makes it competitive for stationary charged electricbuses. Acknowledgment. The research was funded by a grant from the Polish National Science Centre (No. 2016/23/D/HS4/03085).

References 1. Bartłomiejczyk, M.: Dynamic Charging of Electric Buses. De Gruyter Poland, Warsaw (2018) 2. Lenz, E.: Electric bus with IMC from Kiepe Electric: reliable, simple and more cost effective. Fachmagazin V+T Verkehr und Technik, editions 8 + 9 (2017) 3. Bartłomiejczyk, M.: Practical application of in motion charging: trolleybuses service on bus lines. In: 18th International Scientific Conference on Electric Power Engineering, Kouty nad Desnou, Czech Republic, 17–19 May 2017 (2017) 4. Wolański, M.: Economic efficiency of trolleybus transport. In: Wołek, M., Wyszomirski, O. (eds.) The Trolleybus as an Urban Means of Transport in the Light of the Trolley Project. Wydawnictwo Uniwersytetu Gdańskiego, Gdańsk (2013) 5. Lindgren, L.: Full electrification of Lund city bus traffic. A simulation study. Industrial Electrical Engineering and Automation, Lund Institute of Technology, Lund (2015)

Multibody Simulation of Rail Vehicle Running Considering Track Flexibility Ján Dižo1(&), Miroslav Blatnický1, and Stasys Steišūnas2 1

University of Žilina, Univerzitná 8215/1, 010 26 Žilina, Slovak Republic {jan.dizo,miroslav.blatnicky}@fstroj.uniza.sk 2 Vilnius Gediminas Technical University, J. Basanavičiaus g. 28, 03224 Vilnius, Lithuania [email protected]

Abstract. Computer simulations are nowadays widely used tools for investigation of interaction of a rail vehicle and a track. They enable to study many important aspects influencing running properties of a rail vehicle under various operation conditions without having a real vehicle as well as to detect and predict mechanisms of adverse effects incident during a rail vehicle running on a track. A rail vehicle is most often evaluated in terms of running safety and passenger ride comfort. For achieving adequate results from computer simulation there is necessary to create such a model of a rail vehicle and a track, which will represent a real object of the investigation. While in most cases of multibody simulations a model of a rail vehicle is build up and described relatively in detail, a model of a track is not always prescribed including stiffness and damping properties. Therefore the content of this article is focused on evaluation of the fact, how the flexibility of a track influences selected outputs quantities. For assessment of results values of accelerations were chosen. Keywords: Rail vehicle
Multibody model flexibility
Accelerations


Computer simulation
Track

1 Introduction The design of rail vehicles has to meet the relatively strict requirements for commissioning. Production and operation of rail vehicles is closely connected with economic factors. Computational simulations significantly contribute to the estimation and prediction of a vehicle running properties [1, 2]. But on this account there is necessary to create a representative multibody model, which will accurately enough reflect the actual operational conditions [3]. For purposes of simulations of railway vehicles commercial multibody programs are used, which functionalities allow to build up quite detailed model on one hand of a rail vehicle and on the other hand of a track [4, 5]. In virtual modeling and simulations a rigid model of a track is usually used. Such an approach does not always reflect actual operation conditions in wheel/track interaction [6, 7]. In many case of simulation computations the flexibility of a track influences dynamic responses of the whole rail vehicle/track mechanical system [8, 9], manly in case of various parameters of stiffness and damping of a track, e.g. when a rail vehicle enters and leaves a tunnel etc. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 309–319, 2020. https://doi.org/10.1007/978-3-030-38666-5_33

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2 Description of an Used Multibody Model In this work, influence of track flexibility on outputs quantities is presented. Model of a rail vehicle and a track were created in Simpack software. This computational program enables to build up various models of any mechanical system from quite simple subsystem of a transport means, such parts of suspension, and partial systems of drive mechanism (engines, gearboxes, etc.) [10–13], through rail vehicles bogies [14, 15], up to a whole rail vehicle with several bogies even entire trains [16]. 2.1

Model of a Rail Vehicle

For purposes of simulation computations a passenger rail vehicle was used. It is two bogies four axles rail vehicle. In terms of mechanics, it is mechanical system, which consists of rigid bodies connected to each other by means of force elements, which represent coil spring and hydraulic dampers. The rail vehicle multibody model composed of fifteen rigid bodies together, namely one body of wagon, two bogie frames, four wheelsets and eight axleboxes. Figure 1 shows this multibody model and a bogie of the carriage is shown in Fig. 2.

Fig. 1. Multibody model of the analysed carriage.

Fig. 2. A bogie of the analysed carriage.

A guidance of each wheelsets in ensured by axleboxes, which operate in the function of swinging arms. The analysed rail vehicle is equipped with primary and secondary suspensions. The system of primary suspension contains coil springs and hydraulic dampers mounted between each axlebox and a bogie frame in vertical

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direction. As usually, the sufficient comfort for passengers the secondary suspension supplies. The system of the secondary suspension interconnects a body of wagon with bogies. It includes coil springs and hydraulic dampers installed in compliance with Fig. 2, where particular abbreviations mean following: PVD – primary vertical damper, SVD – secondary vertical damper, LD – lateral damper, YD – anti-yaw damper. Table 1 contains some selected inertia parameters of the analysed carriage. Table 1. Selected parameters of the analysed carriage. Body of the carriage Body of wagon Bogie frame Axlebox Wheelset

Mass [kg] 38,000 2,850 215 1,690

Ixx [kg
m2] 58,000 1,950 4,55 880

Iyy [kg
m2] 23,000 1,665 7,1 190

Izz [kg
m2] 23,500 3,330 7,1 880

A model of the wheel/rail contact is one of the most important factors, which influences fidelity of simulation computation [17, 18]. In our model the Fastsim method for computation of the wheel/rail contact was defined. It insures sufficient accuracy and speed of calculation output quantities in the contact patch [19–21]. 2.2

Model of a Track

The track is represented by several data, such as the position coordinates (x, y, z) in respect of considered coordinate system and the orientation angles (u, w, h) representing roll, pitch and yaw angles [22]. Modeling Track Flexibility. Considering the track flexibility in simulation calculations brings more detailed and real sight to virtual simulations in multibody modeling. The used software enables to define track flexibility in several manners. There is

Fig. 3. Scheme of a flexible track.

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possible to add and activate in a model additional force elements for modeling track sleepers and ballast connections with defined stiffness and damping. The exemplificative scheme of a railway track with considered flexibility is shown in Fig. 3. As it is possible to see in Fig. 2, in case of modeling the track flexibility additional bodies representing track ballast with defined mass and inertia properties have to be created. During calculation the force element takes information from joint element about actual position, where the tested rail vehicle is currently located. In presented work, two options of track flexibility were defined. In one option, constant values of stiffness and damping coefficients of the track were chosen (below only ‘constant’) and in the other option, stiffness of the track foundation are prescribed by the sinusoidal function (below only ‘sinusoidal’). The second option simulates regular changes of stiffness-damping characteristics of a flexible track depending on sleepers’ position. In this case, values of stiffness and damping of the track vary in a sinusoidal manner in such a distance frequency, which corresponds to sleepers’ position. The stiffness of the track ki(s) in particular direction x, y or z marking by i varies regarding to the travelled distance s according to the following formulation: ki ðsÞ ¼ ki0 þ kiC
sinðFi
ðsðtÞ  s0 ÞÞ;

ð1Þ

where ki0 is constant stiffness, kiC is amplitude of the track stiffness, Fi is the nominal force acting due to the carriage gravity, s(t) is travelled direction as a depending on the integration time and s0 expresses an offset of the start position. Moreover, two values of stiffness were defined in simulation computations, lower values of stiffness (below only ‘soft’) and higher values of stiffness (below only ‘stiff’) in order to test effects of various values of stiffness on outputs quantities.

3 Simulation Results and Findings This section contains results from simulation computations of the passenger rail vehicle, which run on a track with defined track flexibility and these are compared with outputs quantities for the case of the wagon running on the track with rigid formulation. Influence of track foundation was assessed by means of evaluation of acceleration signals in the vertical directions, i.e. in ‘z’ axis direction, on two positions on the tested rail vehicle, because values of accelerations are standard output quantities, which are measured and evaluated in process of investigation of rail vehicle dynamics [23–25]. Accelerations were measured by two accelerometers located on the right axlebox of the first wheelset (considered in running direction) and on the body floor located over the centre of the first bogie. Simulations were carried out for various running speeds. When we take all values of speeds and various track foundations into account, it results to relatively numbers of performed computations, from which only several are presented. As representative samples results for 60 km/h, 100 km/h and 140 km/h were chosen. Values of accelerations are arranged below in accordance with defined track foundations depending on used combination of values of stiffness, i.e. ‘constant soft’, ‘sinusoidal soft’, ‘constant stiff’ and ‘sinusoidal stiff’ described above and depending on measured position on the rail vehicle, i.e. on axlebox and on floor.

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3.1

313

Evaluation of Accelerations on an Axlebox

Results for the Soft Track Foundation. Firstly, waveforms of accelerations for soft stiffness-damping characteristics on an axlebox are presented. There was selected a short time period for clear visualisation of results (Fig. 4).

Fig. 4. Acceleration on an axlebox for the ‘constant soft’ and ‘sinusoidal soft’ track foundation.

Fig. 5. Acceleration on an axlebox for the ‘rigid’ track foundation.

When reached results are compared each other, we can see, the sinusoidal definition of stiffness-damping characteristics (Fig. 4 lower) causes more significant excitation of the whole rail vehicle mechanical system in comparison with definition of track

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characteristics by constant values (Fig. 4 upper). When track flexibility foundation is compared with rigid track foundation (Fig. 5), certain specific findings are obvious. For chosen assessed operational conditions, definition of track flexibility by constant values of stiffness-damping characteristics does not cause such considerably differences of acceleration outputs in comparison with sinusoidal definition of track flexibility. In this case, values of acceleration are much greater, which would indicate marked vibration of unsprung masses of bogies. Further, we can observe influence of running speeds on values of accelerations. For this influential factor causes expected phenomenon, i.e. amplitudes of outputs are higher for the greater running speed, because it excites vibrations of the observed wheelset and thus also the axlebox. For constant stiffness and rigid track frequencies of accelerations are very close, but the sinusoidal stiffness of track foundation results to higher frequencies of output accelerations. Results for the Stiff Track Foundation. As further assessed results, waveforms of accelerations for stiff characteristics of the track foundation are introduced in Fig. 6. In case of rail vehicle running on the track with defined stiffness-damping parameters of higher values, for our tested running conditions, outputs accelerations on the axlebox have similar waveforms for constant stiffness values and rigid track in comparison with previous assessed conditions and amplitudes and frequencies of accelerations have similar values.

Fig. 6. Acceleration on an axlebox for the ‘constant stiff’ and ‘sinusoidal stiff’ track foundation.

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When the wagon runs on the track with sinusoidal definition of track flexibility, but with higher values, accelerations are even smaller, then in the case of running on the track with ‘softer’ stiffness-damping characteristics. We can note, waveforms of accelerations for running speed of 140 km/h have relatively high frequency of a course. It is obvious from graphs in Fig. 6 lower. 3.2

Evaluation of Accelerations on a Floor

This section contains resulting acceleration measured on the carriage floor. Outcomes for the Soft Track Foundation. Waveforms of accelerations measured on a floor for soft stiffness-damping characteristics are shown in Fig. 7. Looking on Fig. 7 we identify, that values of accelerations on a floor of the tested wagon are much smaller in comparison with values of acceleration measured on the axlebox. It is logical, since the floor of the wagon is isolated from unsprung masses by primary and secondary suspensions. In the case of definition of sinusoidal soft stiffnessdamping parameters greater oscillations of accelerations observed (Fig. 7 lower) in comparison with constant values of stiffness-damping parameters of the track foundation (Fig. 7 upper). Nevertheless, from accelerations waveforms shown in Fig. 7 there is evident, that at set parameters of simulations acceleration for constant values of stiffness and for the rigid track foundation are almost the same. The acceleration for the rigid track foundation are shown as well (Fig. 8).

Fig. 7. Acceleration on a floor for the ‘constant soft’ and ‘sinusoidal soft’ track foundation.

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Fig. 8. Acceleration on a floor for the ‘rigid’ track foundation.

Outcomes for the Stiff Track Foundation. Finally, Fig. 9 shows waveforms of accelerations found on the floor for stiff track foundation. Even in this case, accelerations reach much smaller values in comparison with accelerations on the axlebox. The reasons are the same as described in previous section. Moreover, we can observe, that values of accelerations measured on the wagon floor are for all parameters of the track foundation related to individual running speeds almost the same.

Fig. 9. Acceleration on a floor for the ‘constant stiff’ and ‘sinusoidal stiff’ track foundation.

From reached results of our research presented above following findings can be formulated.

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Decision about setting up the parameters of multibody model of a rail vehicle intended to analyzing its ride properties depends on what parameters the user wants to investigate. As the flexible track foundation increases number of bodies of a multibody model, it leads to increasing the degrees of freedom as well and thus also to increasing number of equations of motion, which have to be solved. Therefore, the computational time is increased as well. In our research, when flexibility of a track foundation was defined, the computational time was increased of approx. 30%. If one wants to investigate only phenomenon related to wagon body, e.g. ride properties for passengers, there would be sufficient to use the rigid track foundation. As ride comfort for passengers is evaluated based on accelerations [26–28], resultant ride comfort indices would not be very different. But, if it would be necessary to assess affects a rail vehicle running on a track, even in case of any wheel untruenesses formed on a wheel tread surface, then definition of track flexibility influences results more markedly. Therefore, future research in thus field will be focused on investigation in more detail, how flexibility formulation in a multibody model effects more outputs parameters.

4 Conclusion In this article modelling of track flexibility and results from simulation computations were presented. As there was presented in the findings and results, considering track flexibility may not always to be necessary and not always improve a multibody model itself. Waveforms of accelerations have shown that definition of track flexibility becomes evident on observed influences only slightly and it results in insignificant changes of outputs values of accelerations. But, in the opposite, various ways of definitions of stiffness-damping characteristics of railway track foundation lead to relatively different values of accelerations measured on rail vehicle’s parts, which belong to unsprung masses. Acknowledgement. The work was supported by the Cultural and Educational Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic in the project No. KEGA 077ŽU-4/2017: Modernization of the Vehicles and engines study program. The work was supported by the Slovak Research and Development Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic in the project No. VEGA 1/5058/18: Research of the interaction of a braked railway wheelset and track in simulated operational conditions of a vehicle running in a track on the test bench.

References 1. Gerlici, J., Sakhno, V., Yefymenko, A., Verbitskii, V., Kravchenko, A., Kravchenko, K.: The stability analysis of two-wheeled vehicle model. In: MATEC Web of Conferences, vol. 157 (2018) 2. Falendysh, A., Volodarets, M., Hatchenko, V., Vykhopen, I.: Software analysis for modeling the parameters of shunting locomotives chassis. In: MATEC Web of Conferences, vol. 116 (2017)

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3. Gerlici, J., Lack, T., Harušinec, J.: Realistic simulation of railway operation on the RAILBCOT Test Stand. Appl. Mech. Mater. 486, 387–395 (2014) 4. Hauser, V., Nozhenko, O.S., Kravchenko, K.O., Loulová, M., Gerlici, J., Lack, T.: Proposal of a mechanism for setting bogie wheelsets to radial position while riding along track curve. Manuf. Technol. 17(2), 186–192 (2017) 5. Nozhenko, O., Hauser, V., Kravchenko, K., Loulová, M.: Reducing tram car’s curve-pasing resistance by double treaded wheel profile. Manuf. Technol. 18(1), 79–83 (2018) 6. Lack, T., Gerlici, J.: A modified strip method to speed up the calculation of normal stress between wheel and rail. Appl. Mech. Mater. 486, 359–370 (2014) 7. Gerlici, J., Lack, T.: Rail geometry analysis (from the point of view of wearing in the operation). Komunikacie 5(1), 43–51 (2003) 8. Vaičiūnas, G., Lingaitis, L.P.: Investigation the dynamics of passenger rolling stock deterioration. Transport 23(1), 51–54 (2008) 9. Gelumbickas, G., Vaičiūnas, G.: Analysis of passenger rolling stock faults and its statistics in Lithuania. Transport 26(3), 315–319 (2011) 10. Baran, P., Štastniak, P., Kukuča, P., Brezáni, M.: Investigation of kinematic parameters of two nonconventional piston machines with wobble board. In: MATEC Web of Conferences, vol. 157 (2018) 11. Baran, P., Kukuca, P., Barta, D., Labuda, R., Drozdziel, P., Pukalskas, S.: The issue of balancing internal combustion engines with non-conventional crank mechanism. Commun. Sci. Lett. Univ. Zilina 19(2), 36–41 (2017) 12. Sapietova, A., Petrech, R., Petrovic, M.: Analysis of the dynamical effects on housing of the axial piston hydromotor. Appl. Mech. Mater. 474, 357–362 (2014) 13. Kasparek, J., Pokorny, P.: Analysis of the dynamics of a virtual prototype wheeled transport machine. In: 18th International Conference on Transport Means, TRANSPORT MEANS 2014, Kaunas University of Technology, Kaunas, Lithuania, pp. 99–102 (2014) 14. Gerlici, J., Gorbunov, M., Nozhenko, O., Pistek, V., Kara, S., Lack, T., Kravchenko, K.: About creation of bogie of the freight car. Commun. Sci. Lett. Univ. Zilina 19(2), 29–35 (2017) 15. Maňurová, M., Suchánek, A.: The analysis of a rail vehicle with a tilting bogie. Manuf. Technol. 16(5), 1020–1027 (2016) 16. Tartakovsky, E., Falendysh, A., Zinkivskyi, A., Mikheev, S.: Refining the models of performing service tests of upgraded locomotives. East. Eur. J. Enterp. Technol. 2(3), 26–31 (2015) 17. Gerlici, J., Lack, T.: Iterative method for railway wheel profile design. Komunikacie 11(2), 49–56 (2009) 18. Vaičiūnas, G., Gelumbickas, G., Lingaitis, L.P.: Methods of research of locomotive axes wear. Transp. Prob. 8(1), 95–103 (2013) 19. Golubenko, A., Sapronova, S., Tkachenko, V.: Kinematics of point-to-point contact of wheels with a rails. Transp. Prob. 2(3), 55–59 (2007) 20. Smetanka, L., Šťastniak, P., Harušinec, J.: Wear research of railway wheelset profile by using computer simulation. In: MATEC Web of Conferences, vol. 157 (2018) 21. Sapronova, S., Tkachenko, V., Kramar, N., Voron’ko, A.: Regularities of shaping of a wheel profile as a results of deterioration of the rolling surface in exploitation. Transp. Prob. 3(4), 47–54 (2008) 22. Kostrzewski, M., Chudzikiewicz, A.: Rail-track quality indicator towards rail vehicle driving dynamics. In: 14th Mini Conference on Vehicle System Dynamics, Identification and Anomalies, VSDIA 2014, Budapest University of Technology and Economics, Budapest, Hungary, pp. 211–218 (2014)

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23. Kostrzewski, M.: Analysis of selected acceleration signals measurements obtained during supervised service conditions – study of hitherto approach. J. VibroEng. 20(4), 1850–1866 (2018) 24. Melnik, R., Koziak, S.: Rail vehicle suspension condition monitoring – approach and implementation. J. VibroEng. 19(1), 487–501 (2017) 25. Melnik, R., Sowiński, B.: The analysis of rail vehicle model eigenvalues for suspension faults detection method. In: 14th Mini Conference on Vehicle System Dynamics, Identification and Anomalies, VSDIA 2014, Budapest University of Technology and Economics, Budapest, Hungary, pp. 39–46 (2014) 26. Gerlici, J., Lack, T., Ondrova, Z.: Evaluation of comfort for passengers of railway vehicles. Komunikacie 9(4), 44–49 (2007) 27. Loulová, M., Suchánek, A., Harušinec, J.: Evaluation of the parameters affecting passenger riding comfort of a rail vehicle. Manuf. Technol. 17(2), 224–231 (2017) 28. Gerlici, J., Lack, T.: Modified HHT method for vehicle vibration analysis in time domain utilization. Appl. Mech. Mater. 486, 396–405 (2014)

Preparation of Parametric Model of Underground Metro Door Force Acting on Coarse Structure Miroslav Blatnický1, Ján Dižo1(&), and Gediminas Vaičiūnas2 1 University of Žilina, Univerzitná 1, Žilina, Slovakia {miroslav.blatnicky,jan.dizo}@fstroj.uniza.sk 2 Vilnius Gediminas Technical University, J. Basanavičiaus g. 28, 03224 Vilnius, Lithuania [email protected]

Abstract. The article deals with the design and use of the underground metro door, taking into account the operational and normative requirements for the underground metro’s outer door. The dimensions of door gained from its previous design will serve as input data for performing technical calculations which will be used to determine the load conditions for the numerical simulation. The aim is using this preparation to obtain all the necessary data entering the analytical calculations for the parametric model creation. This will be able to be used for other door systems of a similar design thanks to the use of variables. The designed door system will meet all imposed requirements on safety, reliability and comfort. Keywords: Underground metro Loading


Door system
Analytical calculation


1 Introduction The number of cities with more than 1 million inhabitants is increasing in the world, and there is insufficient transport by road. There are not many options for solution of this problem [1]. One of them, over ground or underground ways are used. Metro or underground railway is a set of light wagons operated in urban public transport for fast passenger transport in cities [2]. Due to the fact that the metro is mainly in tunnels, the operational requirements are different from railway vehicles and trams operated on the ground [3–6]. The spatial layout of the lines affects the across dimensions of the vehicle and the way the electric current is supplied. Vehicle dimensions are also influenced by the required transport capacity, which affects the vehicle’s length, driving speed and the length of the driving interval. Some of them are equipped with special systems for improving running in curves. Moreover, rail vehicles of the metro have to meet relatively strict criteria related to passenger comfort [7–9] and related to the environment as well [10, 11]. The maximum speed of metro vehicles does not exceed 100 km/h and the typical speed is 80 km/h and the minimum driving range is 75 s. The exchange of passengers at the pit stops at individual stations does not last for more than 25 to 30 s. In the case © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 320–330, 2020. https://doi.org/10.1007/978-3-030-38666-5_34

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of a metro where the door opens and closes quite often, the doors and door mechanisms are heavily loaded, which results in extraordinary demands on the reliability of their function [12, 13]. As time goes by, requirements have been changed for how to open doors. The manual door opening is no longer used today, replaced by pneumatic and electrical systems. This is why there are increased requirements for the reliability of the whole system.

2 Design Requirements for the Underground Metro’s Outer Door In order to solve the problem properly, it is necessary to define the reference vehicle and its parameters to be used. The calculation deals with the real model of the underground metro M1. The main components of the designed door (Fig. 1) include door leaf 1, door control button 3 located on one of the leafs. The door mechanism 2 is located above the door and has a door control computer 5 built in. Emergency unlocking of the door 4 allows unlocking of the closed door and manual opening in case of emergency. The lower door guide 6 is at the bottom of the door.

Fig. 1. Main parts of the metro door.

2.1

A Reference Vehicle

The type drawing of the vehicle considered is shown in Fig. 2. Here can be seen the basic dimensions, the layout of the unit and its shape. It is the metro set of the underground metro M1. It consists of two front wagons (M1.1) and three loaded wagons (M1.2, M1.3, M1.2). Front wagons have cabs of a metro driver which allow equivalent control of the metro from both of these positions. Front wagons are equipped with semi-automatic couplings. Current collectors are located on each bogie on both sides, powered by a third rail. The cabin of each wagon is welded from large extruded aluminium profiles. On both sides of the wagon, there are four sliding doors with a clear width of 1,300 mm.

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Door Design

The minimum doorway width to allow comfortable entry and exit of the passengers is 800 mm. The door has to have a minimum ground clearance of more than 1,900 mm. They must also be equipped with a transparent window to allow passengers to check the presence of the platform. Safety glass must be used. Care must also be taken to a water drain. The door system must include means for diverting water from the roof of the vehicle away from the doorway.

Fig. 2. Drawing of the underground metro M1.

2.3

Door Mechanical Strength

The door must withstand the force that arises when the passenger leans or falls against the door. The force mustn’t cause non-elastic deformation or the door to be uncontrollable. For this purpose, the closed and locked door together with the glass must withstand the force applied from the interior of the vehicle to the door leaf. This load will be represented by the application of a load on a strip of 200 mm height, located l2 = 1,300 mm above the threshold.

Fig. 3. Point of application of loading from passengers.

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The value of this load is 1,000 N for each meter of the load mentioned above (Fig. 3 – 1 outer side of the door, 2 inner side of the door, 3 uncovered inner area, l1 = 100 mm, 12 = 1,300 mm, F = 1,000 N/m). The locking system on the sliding door must withstand a force of 1,200 N in the direction of opening. 2.4

Types of Static Loading of the Handles

Forces in the vehicle equipment handles can be calculated when the masses of the equipment are multiplied by the accelerations resulting from the practice, listed in Table 1. Table 1. Considered accelerations. Acceleration in axis Acceleration Acceleration multiple x g ±3 y g ±1 z g (1 ± c) c = 2 at the end of the vehicle and it decreases linearly up to 0.5 g in the centre of the vehicle. g = 9.81 m/s2

2.5

Definition of a Coordinate System

A coordinate system used for calculation is defined in Fig. 4. The positive direction of the x-axis is parallel to the longitudinal axis of the vehicle and is in the direction of travel. The y-axis corresponds to the transverse axis of the vehicle and is in the horizontal plane. The positive direction of the z-axis goes upward.

Fig. 4. Vehicle coordinate system.

Consequently, a number of requirements must be respected, namely related to fire protection, acoustic insulation, thermal insulation [14, 15], electronic devices, reliability, availability, maintainability, safety, protection against current and environmental conditions and loads caused because of vibration, which rise during running on a track

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at various speeds [16, 17]. The great emphasis is placed on noise protection, because this known negative phenomenon follows every braking process [18–20].

3 Design of a Technical Solution for the Metro Door This section presents a technical solution of the metro door. Virtual models were created by means of three-dimensional modeling, which is fully used in the process of development of rail vehicles [21, 22]. The designed door system is a sliding plug door type (Fig. 5a). The sliding plug doors work by combining two movements. The first movement pushes the door from the sidewall. The second movement moves the door alongside the sidewall. Door ejects in the range from 58 to 65 mm measured from the sidewall. The advantage of these doors is that in the closed position they are located in the plane of the sidewall, therefore they are suitable for mechanized washing, are more aesthetic and have a good tightness. The disadvantage is the duct or a drive that is more complicated than for sliding exterior and pocket door. The maximum dimensions of the system are the following: width 1,856 mm and height 2,190 mm. The height of the door leaf is 2,077 mm and the width is 781 mm. The weight of the door leaf is 50 kg and the top of the mechanism is 80 kg, meaning the entire system weighs 180 kg. The system is driven by an electric motor and the transmission of the power to open/close the door is done by means of a screw and guide nuts.

Fig. 5. Designed door system.

The door system is attached to a coarse structure with screws. In the top mechanism, there are eight screws, four of which are vertically and four horizontally screwed into C grooves on a coarse construction. Figure 5b shows the position of these screws. The remaining eight screws are located along the sides of the door leaves - four to the right and four to the left. The two screws are used to attach the holding arm and the remaining two screws are used to attach the arm of door conduct.

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4 Creation of the Parametric Model We assume that the vehicle is not moving and the doors are locked and closed. We will define the external forces that we will consider as well as the reaction forces that represent the action of the door system on the coarse construction. External forces can act in different combinations. These combinations will be defined in cases of the load. The calculation itself will be implemented in the parametric model and it was created in Microsoft Excel. This model can be used to a quick calculation of the forces acting on the coarse construction for various load cases with the possibility of inserting input parameters as required. The simplified model of the door is shown in Fig. 6. Areas numbered 1 to 7 are the places of attachment of the door system to the course structure. Also, points A, B, C, D, E, F, T1, T2 and T3 represent the effects of individual load forces, contacts of kinematic pairs and the position of weights of considered masses (Table 2).

Fig. 6. Schematically shown door model.

Table 2. A supplementary table to Fig. 6. Point A B C D E F T1 T2 T3

Meaning Point of force action of the passenger on the first door leaf Point of force action of the passenger on the second door leaf Contact place of the guide rail with guide wheel Contact place of the guide rail with guide wheel The socket on the support rod The socket on the support rod Centre of gravity of the upper mechanism Centre of gravity of the first door leaf Centre of gravity of the second door leaf

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Locations 1 and 3 in Fig. 6 are identical. It is the place of fixing the door system to a rough construction by two screws. One screw is placed vertically, the other horizontally. Position 2 consists of two vertically and two horizontally positioned screws (Fig. 7). In the calculation, it will be assumed that all three positions 1, 2 and 3 take the degrees of freedom in all three axes.

Fig. 7. Details of positions 1, 2 and 3.

Positions 4 and 5 represent the holding arm. These positions do not appear in the equations in every case because they only prevent the door from moving in the positive direction of the z-axis. To the rough construction is mounted with two screws. Positions 6 and 7 are bottom door guides. On the course structure, the force effect is transmitted from the door through the swinging arm. In the closed position of the door, they prevent the door from moving in the direction of the x and y-axes. It is attached to the course structure by two screws (Fig. 8).

Fig. 8. Details of positions 6 and 7.

The individual dimensions that will enter the analytical calculation were measured in the CATIA model (Fig. 9). Precise values are stated in Table 3. For a correct and simple solution, it is appropriate to determine which load case will be optimal for the overall solution. After analysing the model, it was determined that the optimal load case will be when a course structure will be loaded at all seven points of contact. Therefore, such load (the most unfavourable) variation has been chosen as given in Table 4.

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Fig. 9. 2D door model with marked dimensions. Table 3. Informative table to the Fig. 9. Dimension a b c d e F g

Value [m] 0.025 0.098 0.861 1.127 2.071 0.147 0.4875

Dimension h i j k l m n

Value [m] 0.7435 0.8226 0.878 0.1205 0.173 0.117 0.06

Table 4. Considered acceleration. Acceleration in axis Acceleration Acceleration multiple g −3 ax ay g −1 az g +3 In the y-direction, a number of additional loads must be counted. g = 9.81 m/s2

For accurate calculation, it is also necessary to consider the loads from the passengers, namely 1,000 N for each meter of the exposed door width in both directions and also the force of the door seal, i.e. 50 N per each meter of the door leaf seal length and reduced to the centre of the door leaf. Last but not least, it is necessary to consider the forces emerging from the difference in the outside pressure relative to the inside of the vehicle, i.e. 1,900 Pa and it is needed to apply the effect to the centre of gravity of the door leaves.

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Future research in this field will be focused on strength analyses of the designed structure using FEM and since there is structure [23], which will be submitted to dynamic loads, analysing of modal properties [24] and creation of a multibody system for identification of dynamic properties is intended [25–27].

5 Conclusion The article describes the issue of the technical design solution of the metro door, indicating all the aspects needed to be considered in their operation with regard to safety. The aim was to prepare the information, dimensions, variables and all the necessary data that are immediately necessary to perform the calculation of the force effect of the door on the course structure due to its operation. The most important aspect is that the door meets safety requirements while respecting all available standards as well as the requirements of the operator of such a set. It can be said that the objective of obtaining the necessary data has been fulfilled. Therefore, it is possible to proceed to the next step of solving this problem which will be the creation of an analytical calculation for obtaining a parametric model of the action of the door on the course structure. Acknowledgement. The work was supported by the Cultural and Educational Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic in the project No. KEGA 077ŽU-4/2017: Modernization of the Vehicles and engines study program. The work was supported by the Slovak Research and Development Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic in the project No. VEGA 1/5058/18: Research of the interaction of a braked railway wheelset and track in simulated operational conditions of a vehicle running in a track on the test bench.

References 1. Kendra, M., Babin, M., Barta, D.: Changes of the infrastructure and operation parameters of a railway line and their impact to the track capacity and the volume of transported goods. Procedia Soc. Behav. Sci. 48, 743–752 (2012) 2. Hauser, V., Nozhenko, O.S., Kravchenko, K.O., Loulová, M., Gerlici, J., Lack, T.: Impact of wheelset steering and wheel profile geometry to the vehicle behaviour when passing curved track. Manuf. Technol. 17(3), 306–312 (2017) 3. Guo, X.X., Pan, X.H., Wang, Z.L., Yang, J., Hua, M., Jiang, J.C.: Numerical simulation of fire smoke in extra-long river-crossing subway tunnels. Tunn. Undergr. Space Technol. 82, 82–98 (2018) 4. Wang, W.H., He, T.F., Huang, W., Shen, R.Q., Wang, Q.S.: Optimization of switch modes of fully enclosed platform screen doors during emergency platform fires in underground metro station. Tunn. Undergr. Space Technol. 81, 277–288 (2018) 5. Bureika, G., Gaidamauskas, E., Kupinas, J., Bogdevičius, M., Steišūnas, S.: Modelling the assessment of traffic risk at level crossing of Lithuanian railways. Transport 32(3), 282–290 (2017)

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6. Sumtsov, A., Falendysh, A., Chyhyryk, N., Vasilenko, O., Vykhopen, I.: Energy saving for the suburban rolling stock. Int. J. Eng. Technol. 7(4.3), 361–365 (2018) 7. Gerlici, J., Lack, T., Ondrova, Z.: Evaluation of comfort for passengers of railway vehicles. Komunikacie 9(4), 44–49 (2007) 8. Lack, T., Gerlici, J.: Analysis of vehicles dynamic properties from: the point of view of passenger comfort. Komunikacie 10(3), 10–18 (2008) 9. Loulová, M., Suchánek, A., Harušinec, J.: Evaluation of the parameters affecting passenger riding comfort of a rail vehicle. Manuf. Technol. 17(2), 224–231 (2017) 10. Leitner, B., Mocova, L., Hromada, M.: A new approach to identification of critical elements in railway infrastructure. Procedia Eng. 187, 143–149 (2017) 11. Luskova, M., Buganova, K., Leitner, B.: Enhancing security of critical infrastructure in sector transport. In: 2nd International Conference on Social, Education and Management Engineering, SEME 2016, pp. 25–29. Destech Publications, Bangkok (2016) 12. Grenčík, J., Poprocký, R., Galliková, J., Volna, P.: Use of risk assessment methods in maintenance for more reliable rolling stock operation. In: MATEC Web of Conferences, vol. 157 (2018) 13. Galliková, J., Stuchlý, V., Poprocký, R., Volna, P.: Model calculations of posterior reliability indicators for the proposal of the maintenance system. In: MATEC Web of Conferences, vol. 157 (2018) 14. Gerlici, J., Gorbunov, M., Kravchenko, K., Prosvirova, O., Lack, T.: Noise and temperature reduction in the contact of tribological elements during braking. In: MATEC Web of Conferences, vol. 157 (2018) 15. Zvolensky, P., Kasiar, L., Volna, P., Barta, D.: Simulated computation of the acoustic energy transfer through the structure of porous media in application of passenger carriage body. Procedia Eng. 187, 100–109 (2017) 16. Saga, M., Jakubovicova, L.: Simulation of vertical vehicle non-stationary random vibrations considering various speeds. Sci. J. Silesian Univ. Technol. Ser. Transp. 84, 113–118 (2014) 17. Yao, S.G., Xiao, X.L., Xu, P., Qu, Q.Y., Che, Q.W.: The impact performance of honeycomb-filled structures under eccentric loading for subway vehicles. Thin Walled Struct. 123, 360–370 (2018) 18. Gerlici, J., Gorbunov, M., Kravchenko, K., Prosvirova, O., Lack, T., Hauser, V.: Assessment of innovative methods of the rolling stock brake system efficiency increasing. Manuf. Technol. 18(1), 35–38 (2018) 19. Gerlici, J., Gorbunov, M., Kravchenko, K., Prosvirova, O., Lack, T.: The innovative design of rolling stock brake elements. Commun. Sci. Lett. Univ. Zilina 19(2), 23–28 (2017) 20. Suchánek, A., Harušinec, J., Loulová, M., Strážovec, P.: Analysis of the distribution of temperature fields in the braked railway wheel. In: MATEC Web of Conferences, vol. 157 (2018) 21. Šťastniak, P., Moravčík, M., Baran, P., Smetanka, L.: Computer aided structural analysis of newly developed railway bogie frame. In: MATEC Web of Conferences, vol. 157 (2018) 22. Šťastniak, P.: Wagon chassis frame design with adaptable loading platform. Manuf. Technol. 15(5), 935–940 (2015) 23. Svoboda, M., Soukup, J., Petrenko, A.: Use of FEM programs in solving general unbalance simple mechanical system of rigid, flexible stored bodies. In: 52nd International Conference on Experimental Stress Analysis, EAN 2014, Jan Evangelista Purkyně University in Ústí nad Labem, Marianske Lazne, Czech Republic (2014)

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24. Klimenda, F., Soukup, F.: Modal analysis of thin aluminium plate. Procedia Eng. 177, 11–16 (2017) 25. Svoboda, M.: Numerical verification of model multibody systems. Appl. Mech. Mater. 486, 239–244 (2014) 26. Sapietova, A., Bukovan, J., Sapieta, M., Jakubovicova, L.: Analysis and implementation of input load effects on an air compressor piston in MSC.ADAMS. Procedia Eng. 177, 554– 561 (2017) 27. Kostrzewski, M., Melnik, R.: Numerical dynamics study of a rail vehicle with differential gears. Procedia Eng. 192, 439–444 (2017)

Investigation of Hydrodynamic Processes in the System – “Pipeline-Fittings” Mykola Karpenko(&) and Marijonas Bogdevičius Vilnius Gediminas Technical University, Plytinės g. 27, 10105 Vilnius, Lithuania {mykola.karpenko,marijonas.bogdevicius}@vgtu.lt

Abstract. The article presents theoretical and experimental researching of hydrodynamic processes in hydraulic drives of vehicles, road building and mining machines. In this work, analyze the influence of hydrodynamic processes on the development of the turbulent flow of a fluid through a “pipeline-fittings” system. The analysis based on the numerical solutions of the Navier–Stokes equations for the velocity field. The research examines the dynamics of fluid flow in the hydraulic system “pipeline-fittings” with the main parameters: flow rate in a system from 20 l/min to 60 l/min, diameter of the pipeline 1/2″ and fittings DKOL standard. The methodology for modeling fluid flow in theoretical studies included high pulsations of the fluid and turbulence calculated. In the experimental part, the losses in the hydraulic system studied with one, two and three fitting connections. Keywords: Hydrodynamic losses


Pipeline
Fittings
Flow coefficient
Minor

1 Introduction High-pressure hoses (HPH) and fittings is two object in connection (see Fig. 1a) what can not existed in hydraulic system one without one. The end fitting of a flexible pipe is a critical component to terminate the ends of each flexible pipe and provide the required connection to mate with the production facilities. It also has a transition function from the low bending stiffness of the flexible pipe to a stiff end. In this type of system – “Pipeline-fittings” exists losses are of two types major and minor. Minor losses are losses due to the change in fluid momentum; they are mainly due to fittings due to bends, sudden changes in diameter, etc. Accuracy of hydraulic calculations is critical for the proper design, operation, and determination of cost for many types of piping systems in residential, commercial, and industrial applications. It is crucial that the engineer understand and apply the correct formula to prevent costly mistakes in the sizing and selection of equipment, operating within safety limits, and avoiding unnecessary modifications later in the process. One aspect that leads to mistakes is the misuse of coefficients that characterize the hydraulic performance of devices that have a fluid flowing through them. According to [1], to calculate losses at hydraulic connections can used the equivalent fitting length method, in which the length of the fitting is only added to the length © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 331–340, 2020. https://doi.org/10.1007/978-3-030-38666-5_35

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of the pipeline. The coefficient of losses at the fitting is replaced by equivalent losses in the pipeline section of a certain length. The main disadvantage of this method is a statics of researching (excluding turbulent losses). For cases requiring more detailed calculation using the empirical formula of DarcyWeisbach [2], whose advantage over the Hazen-Williams formulas is a possible calculation of pressure losses with a developed turbulent flow of an incompressible fluid on hydraulic resistances. The loss ratio Dp in a given local resistance to velocity head v2/2 is called the local resistance coefficient n and is denoted by Weisbach-Darcy formula by [2] for each local resistance, and, in sum, for all local resistances: Dp ¼

X v2 n q; 2

ð1Þ

where n – coefficient of local resistance (usually determined experimentally is in reference books); v2 – the average velocity of fluid flow; q – fluid density. To overcome the resulting hydraulic resistance is expended engine power, the calculation of which is carried out to the formula from [2]: DN ¼

n X i¼1

DNi ¼

n 1 X DQi Dpi ; gp gd i¼1

ð2Þ

where Dpi – hydraulic loses at the i-th hydraulic element of system, ηp – efficiency pump-motor, ηp – efficiency of pump-motor drive. Given the complexity and branching of modern hydraulic systems of transport vehicles, shown in Fig. 1b [3], sometimes the number of connecting fittings and HPH can reach more than hundreds, in the manipulator HANGCHA CPCD 160-G35 there are 128 of HPH with different fittings [3].

a

b

Fig. 1. Typical hydraulic components of the system: a – HPH with fitting; b – part of the hydraulic.

This significantly affects the pressure loss and power in the system, the dynamics of fluid flow, vibration and noise. At the same time, theoretical studies of pressure loss on fittings considered only at static fluid flow, and values taken approximate established experimentally in the middle of the 1970s and 1980s.

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The more different elements and adapters in the system, the greater the pressure loss, which negatively affect the energy parameters of the drive mechanism (energy consumption). Also on the loss of pressure affects the wrong selection of elements. The same elements but different diameters of the working fluid pass can reduce the pressure in the system in general, since more fluid is needed to pass their plane. The main task of researching accurately analyze the influence of numerous factors on the dynamic fluid behavior, pressure losses and resistance coefficient on the real model of connections fittings and HPH.

2 Object Parameters Depending on the shape, direction, standard and other parameters of the system, the fittings can have different shapes and diameters. The structure of any fitting, for connecting the HPH, includes two main elements or one of them when connected to hydraulic equipment: nipple with fixing nut or connecting nipple. There is a wide variety of fittings standards, according to the data of the company [4]. From data base can be noted the four most common standards in hydraulic systems: BSP, JIS, ORFS and DKOL (DKOS). For research selected most popular standard in Europe – DKOL. Shown in Fig. 2a DKOL/DKOS connection with cylindrical metric thread, made according to the European metrical standard [5]. For the accuracy of the simulation, was created 3D models of DKOL/DKOS fittings standard. 3D model of European standard DKOL/DKOS fittings shown in Fig. 2b. Inlet and outlet diameters of fittings connections 9.5 mm with growing size at middle of connection up to 14.3 mm. The main problem is the size changes, and the configuration of the cross-sectional area of the HPH fittings (the cut in the connection of the DKOL/DKOS fittings is shown in Fig. 2b). One with the most frequently used HPH diameter for replacement and the design of new hydraulic systems is with the number of conditional passage 08 DASH – which is equal to the diameters of the conditional pass 1/2″ or 12.7 mm, which is accepted for research.

a

b

Fig. 2. European standard fitting (metrical): a – DKOL/DKOS fittings standard; b – 3D modeling DKOL/DKOS fittings standard with incision of connecting.

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For modeling was using hydraulic oil Hydraux HLP 46 what conforms to the standard DIN 51524-2 [6]. Property of fluid showed at Table 1. Pressure in outlet of system set around 2 MPa, fluid flow rate rising from 20 l/min up to 60 l/min. Table 1. Oil properties. 3

Density (kg/m ) Temperature (°C) Kinematic viscosity (mm2/s) 874 40 46

3 “Pipeline-Fitting” System Modeling by CFD 3.1

Movement and Continuity Equations

Movement of liquid is accepted as 3-dimensional and unsettled, all local velocities are considered. The liquid movement is considered as 3-dimensional, all local velocity is equal to average velocity, and unsettled. Velocity and pressure depend on longitude coordinate and time. Such liquid movement is characterized by the wave of increased and reduced pressure which spreads from the place of change in each pressure vibration cross-section and in deformation of walls. The liquid is double-component mixture, including gas (air). The dynamics of an incompressible and Newtonian fluid flow is governed by the Navier–Stokes equations representing the momentum conservation. Since, from the mass conservation, the divergence of the velocity field is zero (∇u = 0). Movement and continuity equations of viscous, compressible fluid in pressure pipe have the following form [7]: h i @sxy @sxz 1 @sxx ¼  @p þ þ þ @x @y @z Re h @x i @ ðqv2 Þ @syy @syz @ ðqvÞ @ ðquvÞ @ ðqvwÞ @p 1 @sxy ; þ þ þ ¼  þ þ þ @y @y @y @z @t @x @z Re h@x i 2 @ qw ð Þ @syz @ ðqwÞ @ ðquwÞ Þ @szz 1 @sxz þ @ ðqvw ¼  @p @z þ Re @x þ @y þ @z @z @t þ @x @y þ

ð3Þ

@q @ ðquÞ @ ðqvÞ @ ðqwÞ þ þ þ ¼ 0; @t @x @y @z

ð4Þ

@ ðquÞ @t

þ

@ ðqu2 Þ @x

þ

@ ðquvÞ @y

þ

@ ðquwÞ @z

where x, y, z – coordinates; u, v, w – velocity components; t – time; q – density; s – stress; Re – Reynolds number. The computations are carried out with commercial CFD software ANSYS® FLUENT®. The simulation software was configured for steady-state fluid flow study in 3D geometry, the standard k – e turbulence model was chosen to conduct fluid flow

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analysis. When applying standard k – e turbulence model the following transport equations for turbulent kinetic energy k and turbulent dissipation e are implemented [8]:    l @k lþ t þ 2lt Eij Eij  qe; rk @xj    @ @ @ lt @e e e2 ðqeÞ þ ðqeui Þ ¼ lþ þ C1e ð2lt Eij Eij Þ  C2e q ; @t @xi @xj k re @xj k @ @ @ ðqkÞ þ ðqkui Þ ¼ @t @xi @xj

ð5Þ

where ui – velocity component for corresponding direction, Eij – component for rate of deformation, rk , re – turbulent Prandtl numbers for k and e, lt – eddy (turbulent) viscosity, determined from the following equation: lt ¼ qCl k 2 =e; C1e , C2e , Cl , are constants (see Table 2). Table 2. Constants of k – e turbulence model. Cl

C1e

C2e

rk

re

0.09 1.44 1.92 1.00 1.30

3.2

Boundary Conditions

There are number of boundary conditions that we will use to solve incompressible Navier-Stokes Equation and k – e turbulence model. The Fig. 3 shows an example how the boundary conditions could be applied. Inflow/Outflow Boundary Condition. For inlet, imposed velocity i.e. the velocity vector normal to the boundary can be specified by: u
n ¼ u0 ;

ð6Þ

which is denoted as the Inflow/Outflow boundary condition. In the above equation n is a unit vector that has a direction perpendicular to a boundary or normal to a boundary. Outflow/Pressure Boundary Condition. For outlet, we can impose a certain pressure in the Outflow/Pressure boundary condition: p ¼ p0   : pI þ l ru þ ðruÞT ¼ p0

ð7Þ

Slip/Symmetry Boundary Condition. The Slip/Symmetry condition states that there are no velocity components perpendicular to a boundary. n
u ¼ 0 or u ¼ 0:

ð8Þ

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Fig. 3. Boundary conditions of system “Pipeline-fittings” for ANSYS Fluent modeling.

3.3

ANSYS Fluent Modeling of “Pipeline-Fittings” System

Due to changes in the size and configuration of the cross-sectional area, the flow velocity, the separation of the transit flow from the walls of the channel and the formation of vortex occur at the fittings connection (see Fig. 4). In this case, there is a continuous exchange of fluid particles between the mainstream and the vortex part of it. The main vortex generates other, smaller whirlwinds that are carried away by the flow and at the same time disintegrate into even smaller whirlwinds. Thus, energy loss occurs not only in the main vortex, but also along the length of the next section of the flow. As a result getting pressure drop in system “Pipeline-fittings” (total pressure in system “Pipeline-Fitting” see Fig. 5 and turbulence kinetic energy see Fig. 6).

Fig. 4. Velocity magnitude by fluid flow vectors in system “Pipeline-fittings” by Fluent modeling.

Fig. 5. Total pressure in system “Pipeline-Fitting” by Fluent modeling.

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Fig. 6. Turbulence kinetic energy in system “Pipeline-Fitting” by Fluent modeling.

From modeling can be see that due to changes in the size and configuration of the cross-sectional area at fittings connection that turbulence kinetic energy grooving up from 0.689
10−4 m2/s2, at inlet of fittings connections, up to 4.92 m2/s2, at outlet of fittings connections, what produce big turbulence in system after passing fittings connections. 3.4

Results

As results from Fluent modeling getting fluid pressure drop thought DKOL fittings connection at different flow rate (see Tables 3 and 4). Table 3. Results of Fluent modeling (1/2). Flow rate (l/min) Flow speed (m/s) Pressure drop (Pa) 20 2.11 1,871 25 2.57 2,786 30 3.11 3,907 35 3.62 5,165 40 4.16 6,604 45 4.65 8,267 50 5.17 10,167 55 5.68 12,293 60 6.21 14,619 34* 3.47 4,827

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The local pressure losses corresponding by the valves and fittings in the hydraulic networks, conversely, it is possible to know the value of n according to the pressure loss: 2Δp ρ v2 ξ ξ= 2 Δp = ξ ð9Þ 2 ρv This calculation must be carried out separately for each pipe size, using the appropriate velocity within that pipe section. The flow coefficient of a device is a relative measure of its efficiency at allowing fluid flow. It describes the relationship between the pressure drop across an orifice, valve or other assembly and the corresponding flow rate. Mathematically the flow coefficient l (or flow-capacity rating of valve) can be expressed from equation: Q l ¼ pffiffiffiffiffiffiffiffiffiffiffiffiffi ; A 2Dp=b

ð10Þ

where b = (1 − (d/D)4); D – diameter of pipeline; d – average diameter of fitting; Q – flow rate; A – average cross section area; Dp – pressure drop; q – fluid density; l – flow coefficient (Fig. 7). Table 4. Results of Fluent modeling (2/2). Flow rate (l/min) Resistance coefficient Flow coefficient 20 0.998 0.829 25 0.953 0.848 30 0.931 0.859 35 0.901 0.872 40 0.883 0.881 45 0.874 0.886 50 0.872 0.887 55 0.870 0.888 60 0.870 0.8884 34* 0.916 0.866

Fig. 7. Flow coefficient of DKOL fitting connection.

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4 Experimental Part Experimental stand for researching hydrodynamic processes in the system “PipelineFittings” showed at Fig. 8. All parameters of stand equipment and flow characteristics introduced at [9]. Experimental stand included tank station with hydraulic fluid and axial-piston pumps inside 1, axial-pistons pump connections with AE. From the pump outlet through a metal pipeline 3 connecting distributor with safety valve 4 and electrical manometer with output signal 5. Though pipeline (HPH) 6 in system connected fittings 8 with two electrical manometers with output signal 7 on both sides of fittings. In outlet of hydraulic line system installed throttle 9. The hydraulic system has a closed circuit with an outlet back to the tank station. All electrical manometers with output signal connections with computer 10 for data recording.

Fig. 8. Experimental stand for researching hydrodynamic processes in system “HPH – fittings”.

At Fig. 9 showed fittings connection at experimental research and graph of different (pressure losses) pressure at outlet and inlet of fittings connections. The experimental data are presented for one two and three fitting connections in the hydraulic system. For each number of fittings, three experiments were conducted to eliminate data distortions.

a

b

Fig. 9. Fittings connection at experimental research: a – view of fittings connection; b – graph of different (pressure losses) pressure at outlet and inlet of fittings connections.

From the graph of different (pressure losses) pressure at outlet and inlet of fittings connections it can be seen that the losses at the fittings, although not significant but

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exponentially increase with the number of fittings (increased from 0.0045 MPa at one (what similar by Fluent modeling at flow rate around 34 l/min) to 0.0074 MPa at three fittings). Although the pressure losses for one fittings connection are not large, in modern transport vehicles can be over 200 different fittings connections that significantly affect the resistance and loss in the hydraulic system.

5 Conclusions On the basis of theoretical research was modeling hydrodynamic processes in the system – “Pipeline-fittings”. Results showed that due to changes in the size and configuration of the cross-sectional area, the flow velocity, the separation of the transit flow from the walls of the channel and the formation of vortex occur at the fittings connection. As a result, we get pressure drop in system “Pipeline-fittings” by different fluid flow (from 20 to 60 l/min) and determinate resistance coefficient (from 0.998 to 0.87) and flow coefficient (from 0.829 to 0.888) at this fluid flow. The difference between the data obtained in the simulation (pressure drops 4,827 Pa at fluid flow 34 l/min) and experimental data (around 4,500 Pa pressure drops at fluid flow 34 l/min) is 8%. On the basis of the experimental data, it is established that pressure losses at fittings, although not significant for one but increase with the increase in their quantity in the systems, from 0.0045 MPa at one fitting until 0.0074 MPa at 3 fittings.

References 1. Bashta, T.M., Rudnev, S.S., Nekrasov, B.B.: Hydraulics, Hydraulic Machines and Hydraulic Drives: A Textbook for Machine-Building Universities. Mechanical Engineering, Moscow, 423 p. (1982) 2. Technical paper. Flow of fluids through valves, fittings and pipe. Metric edition – SI units. Crane co., New York, 133 p. (1982) 3. Karpenko, M., Pelevin, L., Bogdevičius, M.: Prospect of using a hydraulic power-saving drive. Techno-technological problems of service, vol. 3, no. 41, pp. 7–12 (2017). (in Russian) 4. Internal statistics from Ltd. “Hydrohouse”. Kiev, Ukraine. Can be requested from the author. http://www.hydrohouse.com.ua 5. DIN 20066/3861. Metric hose fittings conform to DIN & SAE standards. German National Standard, Berlin, 17 p. (2006) 6. DIN 51524-2. Pressure fluids - Hydraulic oils - Part 2: HLP hydraulic oils, Minimum requirements. Standard by Deutsches Institut Fur Normung E.V. (German National Standard) (2017) 7. Foias, C., Manley, O., Rosa, R.: Navier-Stokes Equation and Turbylence. Cambridge University Press, Cambridge (2001) 8. Launder, B., Spalding, D.: Lectures in Mathematical Models of Turbulence. Academic Press, London (1972) 9. Karpenko, M., Bogdevičius, M.: Investigation of hydrodynamic processes in the system — “axial piston pumps – pipeline – fittings”. In: VII International Symposium of Young Researches – Transport Problems. Katowice, Poland, pp. 832–843 (2018)

Innovative Technical Solutions to Improve the Cooling Efficiency of Friction Brake Elements Juraj Gerlici1(&), Kateryna Kravchenko1, Vladimir Hauser1, Mykola Gorbunov2, Tomas Lack1, and Valentin Mogila2 1

University of Zilina, Univerzitná 8215/1, 01026 Zilina, Slovak Republic {juraj.gerlici,kateryna.kravchenko, vladimir.hauser,tomas.lack}@fstroj.uniza.sk 2 Volodymyr Dahl East Ukrainian National University, Central Avenue 59a, Severodonetsk 93400, Ukraine [email protected], [email protected]

Abstract. The article deals with the problem of friction brake elements cooling while braking. A significant increase in temperature on the brake elements surface dramatically reduces the friction coefficient. This negatively affects the braking performance, leads to wear increasing, cracks formation and to the failure of entire brake system. This way, vehicle safety can be reduced. While braking, it is necessary to stabilize the temperature of the brake friction elements. Nowadays, the most common construction to ensure stable operation of brake elements are using ventilated discs. The cooling of the discs is intensified by means of ventilation channels of various geometry types. The main advantage of this design is that disc cooling surface works when braking up to certain speed. But the significant disadvantage is that train movement resistance is increased because of air pumping effect also when discs does not need to be cooled. This paper proposed several methods for the brake friction elements temperature stabilizing by increasing the air circulation along brake disc vanes, as well as by using additional phase transition materials in brake pads. Keywords: Friction brake elements limiter
Half-Bell shaped elements


Phase transition material
Air flow

1 Introduction Safety of the vehicle strongly depends on stable operation of the braking system [1, 2]. The temperature in the friction elements contact has a significant effect on braking efficiency. Temperature in the contact zone considerably increases during operation of brake elements. In case of drag (downhill) braking, this occurs wear increasing and early crack forming. The tests carried out in laboratory conditions by using the friction test stand and the test bench [3–5] showed that the initial contact temperature rise results in increasing of the friction coefficient. The critical temperature depends on the contacting bodies’ materials and structure, the ambient air temperature and other factors. When it is reached, a severe decrease of friction coefficient occurs. This adversely © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 341–349, 2020. https://doi.org/10.1007/978-3-030-38666-5_36

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affects braking properties of the rolling stock. The designers and operators face the challenge of developing new construction of brake elements that will allow controlling the temperature in the contact, keeping the optimum friction coefficient and providing higher wear resistance of friction surfaces.

2 Analysis of the Friction Elements Temperature Stabilization Methods One of the factors which significantly affects safety of railway vehicles operations is the interaction of elements in the brake system, which ensures the braking process implementation reliability [6–8]. In rail transport, a significant part of the accidents is caused by the structural defects of the rolling stock, occurred as a result of problems with its brake equipment [9, 10]. Nowadays, the most common construction to ensure stable operation of brake elements are using ventilated discs. The cooling of the discs is intensified by means of ventilation channels of a different geometry, as shown in Fig. 1. It is necessary for the channel geometry to allow the flow of such an amount of air to provide the required cooling power of the brake elements. The main advantage of this design is that disc cooling surface works when braking up to certain speed. But the significant disadvantage is that train movement resistance is increased because of air pumping effect also when discs does not need to be cooled. According to the preliminary calculations and studies [10] dealing with disc brake resistance, the train power may be reduced by 2.3–4.2% depending on the speed and length of the rolling stock as well as by number of disks situated on the wheelset. Therefore in case of use such disk brake structure, it may be helpful to use construction elements to prevent the air flow in the brake discs ventilation channels while vehicle running.

Fig. 1. Brake discs geometry: (a) disc without channels; (b), (c), (d) disc with radial vanes; (e), (f) disc with ventilation bars; (g), (h) disc with tangential vanes; (i) disk with ventilation bars and protrusion system on the inner wall of the channels.

In operational practices as well as in scientific research works of leading scientists dealing with new construction of brake elements, ways for cooling and friction contact temperature stabilizing this options are investigated: • using ventilated discs [11]; • forced air flow supply in the friction elements contact [9];

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• forced air supply, the temperature of which is regulated depending on conditions and modes of operation; • using of pads with porophore inserts with forced air supply, the temperature of air is regulated [12]; • using of pads with cooling ribs [13]; • application of brake pads with outer surface cowered with heat dissipating material; • supply of friction activators in the friction elements contact zone.

3 Innovative Proposals for Stabilizing the Coefficient of Friction (by Temperature) in Tribocontacts “Brake Disk – Brake Pad” Authors proposed several innovative methods with the aim to create the optimum temperature regime while braking. To do this, new and modified elements in the brake assembly constructions were used. Materials with phase-transitions were used. For the proposed solutions, patent application have been placed. Three of them are described in the following. 3.1

Increasing of Heat Removing Effect from Brake Friction Elements by Brake Pads

By authors proposed method for creating the optimum temperature regime during braking, patent application number a201712235 from 2017-12-11 is the use of additional materials with first kind phase transition in the design of brake elements. The phase state is understood as the thermodynamic equilibrium state of the substance that differs in physical properties from other possible equilibrium states of the same substance. Within one aggregate state, the substance can be in several phase states, differing in their properties, composition and structure. The transition of a substance from one phase state to another - a phase transition - is always associated with qualitative changes in the properties of the substance (changes in the aggregate state of the substance or transitions associated with changes in the composition, structure, and properties of the substance). The first-order phase transition (thermal phase transition) is accompanied by heat absorption and is characterized by a constant temperature, changes in entropy and volume. The heat supplied to the body goes not to heating the body, but to breaking the interatomic bonds. Structurally, the brake pad with increased energy capacity contains cavities for placing materials with thermal phase transitions of the first kind. For the reason that depending on the volume of the material and the temperature of the thermal phase transition, the absorbing capacity of the heat from the pad varies, subsequently the design provides for the presence of several types of materials with phase transitions. For example, material n1 with a thermal phase transition temperature of 150–200 °C, n2-nn is above 200 °C. Such solution will allow to stabilize temperatures and friction coefficient over a wide range of values.

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When friction heating of the pad base material and it reach the temperature T1 of the f1 material thermal phase transition, a transition occurs from one phase state to another, which is accompanied by heat absorption Q1, Q2, …, Qn (Fig. 2) and temperature stabilization of the friction pair. The transition time is fixed (t1, t2, …, tn) and depends on the f1 material volume. Similar processes occur with other materials of fn inserts of the brake pad when reaching higher temperatures as shown in Fig. 2. When the train stops, the generation of heat from the friction pair also stops and a reverse phase transition occurs. By cooling the base material of the pad, the aggregate state returns to its original state.

Fig. 2. Changing the brake pad temperature with increased power consumption during braking.

It can be seen from the Fig. 2 that the critical temperature Tcr of the pad material, which leads to deterioration of the pad friction parameters and to increased wear, is not achieved when using elements with a phase thermal transition, which allows to stabilize the temperature and coefficient of friction in the contact, to improve the braking efficiency, to reduce wear and rolling noise level. 3.2

Increasing of Heat Removing Effect from Brake Disc by Adding New Elements

The bigger amount of air pass through the disc’s ventilation channels, the strongest heat removal effect from the friction surface can be reached. It is proposed to increase the amount of caught air for brake disc cooling by additional elements. The authors proposed two ways to do this (patents application a201712176 from 2017-12-11, a201712177 from 2017-12-11). (A) Using of two additional elements installed on the brake disc centre A significant increase in temperature on the brake elements surface dramatically reduces the friction coefficient. This negatively affects the braking performance,

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leads to wear increasing, cracks formation and to the failure of entire brake system [14, 15]. This way, vehicle safety can be threatened. While braking, it is necessary to stabilize the temperature of the brake friction elements. In this case, by the ventilation channels 3 (Fig. 3) and routing air into them. Air routing into the ventilation channels 3 of the brake disc 2 is provided by additional half-bell shaped elements 5. They are located in a vertical section of the brake disc 2 on both sides of its axial gaps 4 and are concentric with the axis of the wheelset 1. The half-bell shaped element 5 is faced to the axial gap 4 of the brake disc 2 (Fig. 3). While vehicle moving (braking), the half-bell shaped elements 5 are catching air and routing it into the axial gaps 4 of the brake disc 2 (Fig. 4). The speed and pressure of the air flowing through the ventilation channels 3 increases. Air-pumping resistance is reduced by increasing the pressure and speed of air flow through the ventilation channels 3. The pressure and speed of the air in cannels 3 are higher than the ones on the ambient air on brake disc perimeter. This fact leads to the reduction of the airpumping resistance.

Fig. 3. Brake disc with half-bell shaped elements.

Fig. 4. Air circulation visualisation.

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The authors have modelled the process in the SolidWorks Flow Simulation. According to the simulations, using of the proposed method can reduce the air pumping resistance and increase the volume of air flowing through the disc cooling channels. This will be helpful for increase the heat removal effect from the brake disc. Proposed method appears to be perspective for high-speed rolling stock. Improved cooling system can help to increase vehicle operation life and ride safety. Using the proposed design allows: – increase the speed and volume of air that flows through the ventilation channels; – reduce the brake disc air pumping resistance due to the fact that the speed and pressure of air in the ventilation ducts is higher than the ones of the ambient air; – increase wear-resistance of friction elements by increasing the heat outflow from them, thereby extending their service life and driving safety; – increase disk cooling, respectively stabilize the temperature of the brake disk, improve braking efficiency.

(B) Using of an additional element installed on the brake disc perimeter To improve the efficiency of the friction brake elements operation, it is proposed to limit incoming ambient air flow to the brake disk 2 and so increase the air flow to the ventilation channels 3 of the brake disk 2 (Figs. 5 and 6). For this purpose, a half-ring shaped limiter 6 was proposed. It is installed on the brake disc perimeter, with small clearance between disc and the limiter. The location of the limiter 6 need to be changed depending on the direction of vehicle ride.

Fig. 5. Brake disc with ambient air limiter.

When braking, to stabilize the temperature of the brake disc 2 installed on the wheelset axis 1, some air is caught by the gaps 4 of the brake disc 2 (Fig. 6). Next, the air enters the ventilation channels 3 and exits between the vanes on the perimeter 5 of

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the brake disc 2. The air leaving the ventilation channels 3 from the front side (in the vehicle ride direction) of the brake disc 2, enters the inner side of the limiter 6, follows it to its lower part and there is blown off to the ambient. At the same time, the oncoming air flow will not affect the movement of air that escapes from the brake disc. This will increase the amount of air that passes through the ventilation channels and so improves the cooling effect. The authors have modelled this process using SolidWorks Flow Simulation. The simulation have shown that the limitation of the ambient air in the openings 4 of the ventilation ducts 3 which are located on the brake disk 2 perimeter 5 allows an increase in the volume of air passing through the ventilation ducts 3, air pumping resistance can be significantly reduced.

Fig. 6. Air flow through brake disc-section view.

Using the proposed technical solution in operation can results in: – eliminate the pressure of the ambient air on the blown off air by installing a limiter; – increase the volume of air that flows through the cooling channels; – increase brake elements wear resistance by increasing the heat outflow from them, thereby extending their service life and improving ride safety.

4 Conclusions A significant increase in temperature on the brake elements surface dramatically reduces the friction coefficient. This negatively affects the braking performance, leads to increasing of wear, cracks formation and to the failure of the entire brake system. This way, vehicle safety can be threatened. While braking, it is necessary to stabilize the temperature of the brake friction elements.

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Using of the proposed methods can stabilize the temperature by thermal phase transitions in brake pads, reduce the air pumping resistance and increase the volume of air flowing through the disc cooling channels. This will be helpful for increase the heat removal effect from the brake disc. Proposed methods appears to be perspective for high-speed rolling stock. Improved cooling system can help to increase vehicle operation life and ride safety. Acknowledgements. The work was supported by the Cultural and Educational Grant Agency of the Ministry of Education of the Slovak Republic in project No. KEGA 077ŽU-4/2017: Modernization of the Vehicles and engines study program. The work was also supported by the project No. APVV-0842-11: Equivalent railway operation load simulator on the roller rig and VEGA No. 1/0558/18: Research of the interaction of a braked railway wheelset and track in simulated operational conditions of a vehicle running in a track on the test stand. Research-Educational Center of Rail Vehicles (VVCKV).

References 1. Gerlici, J., Lack, T., Harušinec, J., Müller, R., Doležel, P.: RAILBCOT rail vehicles brake components test stand. In: Proceedings of PRORAIL 2011 Žilina, Scientific and Technical Society at the University of Žilina, pp. 233–241 (2011) 2. Dižo, J., Steišūnas, S., Blatnický, M.: Simulation analysis of the effects of a rail vehicle running with wheel flat. Manuf. Technol. J. Sci. Res. Prod. 16(5), 889–896 (2016). ISSN 1213-2489 3. Gerlici, J., Lack, T.: Rail vehicles brake components test bench utilization. In: Applied Mechanics and Materials, 51st International Scientific Conference on Experimental Stress Analysis (EAN 2013), vol. 486, pp. 379–386 (2014) 4. Fomin, O.: Modern requirements to carrying systems of railway general-purpose gondola cars. Sci. Tech. J. Metall. Min. Ind. 5, 31–43 (2014) 5. Dižo, J., Steišunas, S., Blatnický, M.: Vibration analysis of a coach with the wheel-flat due to suspension parameters changes. Procedia Eng. 192, 107–112 (2017) 6. Gorbunov, M., Domin, R., Kovtanec, M., Kravchenko, K.: The multifunctional energy efficient method of cohesion control in the “wheel-braking pad-rail” system. In: Prace Naukowe Politechniki Warszawskiej – Transport. Międzynarodowej Konferencji Naukowej TRANSPORT XXI WIEKU, Arłamów, pp. 114–126 (2016) 7. Štastniak, P., Smetanka, L., Moravcík, M.: Structural analysis of a main construction assemblies of the new wagon prototype type zans. Manuf. Technol. 18(3), 510–517 (2018) 8. Smetanka, L., Štastniak, P.: Analysis of contact stresses of theoretical and worn profile by using computer simulation. Manuf. Technol. 17(4), 580–585 (2017) 9. Gorbunov, N., Kravchenko, E., Demin, R., Nogenko, O., Prosvirova, O.: Analysis of technical solutions aimed at improving the energy dissipating capacity of elements of brake systems, In: Visnik of the Volodymyr Dahl East Ukrainian National University, Lugansk, P1, vol. 18, no. 207, pp. 57–61 (2013) 10. Gorbunov, N., Kravchenko, E., Demin, R., Nogenko, O., Prosvirova, O.: Analysis of technical solutions aimed at improving the energy dissipating capacity of elements of brake systems. In: Visnik of the Volodymyr Dahl East Ukrainian National University, Lugansk, P1, vol. 18, no. 207, pp. 57–61 (2013) 11. Tirovic, M.: Energy thrift and improved performance achieved through novel railway brake discs. Appl. Energy 86, 317–324 (2009)

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12. Gorbunov, N., Kravchenko, E., Prosvirova, O., Nogenko, V.: Brake pad. Utility Model № 91592, Brake pad, № 13 (2014) 13. Lukonin, V.S., Maltsev, A.A.: Brake pad. Patent for Invention № 75974, Brake pad, № 6 (2006) 14. Gerlici, J., Gorbunov, M., Kravchenko, K., Prosvirova, O., Lack, T., Hauser, V.: Assessment of innovative methods of the rolling stock brake system efficiency increasing. Manuf. Technol. 18(1), 35–38 (2018) 15. Gerlici, J., Gorbunov, M., Kravchenko, K., Prosvirova, O., Lack, T.: The innovative design of rolling stock brake elements. Commun. Sci. Lett. Univ. Zilina 19(2), 23–28 (2017)

Research on the Rotation Vibration in the Transmission with Gear Box Defects Paulius Bogdevičius(&), Marijonas Bogdevičius, and Olegas Prentkovskis Department of Mobile Machinery and Railway Transport, Vilnius Gediminas Technical University, Plytinės g. 27, 10105 Vilnius, Lithuania [email protected]

Abstract. The article presents theoretical research of rotation vibrations in the transmission system. Transmission with an idle consists of electrical motor, gear box and connecting shafts. In the gear box some teeth have different size of the defects (0%, 20%, 50%, 80% of teeth width). In the dynamics model of gears, the deformation of each tooth and backlash between connection of the gear teeth are evaluated. The dynamics of the transmission is described using finite element method and discreet elements. The paper presents and analyses the results of mathematical experiment on this system. Keywords: Gearbox


Transmission
Contact
Mesh stiffness

1 Introduction Gearbox is the main transmission element in all transport machine applications for transmit power. Gear or gear teeth’s surfaces in particular excessively wear because of the difficult shape of geometry caused by intense loads in transmission systems. Defects such as gear tooth cracks and stress ruptures increase vibration levels and transmits noise simultaneously as gearbox continues to work. Early fault detection might be a crucial part for stopping incoming system failure. At present, many scientists perform mathematical modeling of gear tooth defects to understand their impact on system dynamic characteristics. Finite element modeling (FEM) is one of the popular methods to simulate dynamic behavior of gears with defects, however these models have large amount DOF therefore modeling process becomes quite difficult to proceed. For example, at [1] the proposed nonlinear tooth contact and mesh stiffness variation model using FEM, in [2] with the same gear teeth contact model indicated that uneven loading on the teeth was because of differing constraints on the two sides of the teeth compared to experiment results. In work [3] studied 3D dynamic contact problems. According to the results, mesh stiffness results were the same as calculated from the conventional methods, case of initial speed impact is considered, the contact time is independent from the initial speed and the impact time depends from geometric parameters of the gear drive and total contact force is proportional to initial speed and transmission load. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 350–360, 2020. https://doi.org/10.1007/978-3-030-38666-5_37

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To insure lifetime of the gear, stiffness calculation is one of the key parameters, which good being studied by [4] presented work of torsional stiffness evaluation in involute spur planetary gears in mesh using FEM. The theoretical gear contact position was determined using an ANSYS APDL software. With this at [5] investigated dynamics of two-stage gear system involving backlash and time dependent mesh stiffness. To satisfy some conditions, nonlinear dynamic system was linearized to linear dynamic system. Evaluating different crack size and pinion’s displacement one of main problem for mathematic simulation, for example, at [6] studied gear system using three different dynamic models from 6 to 12 degrees of freedom (DOF) evaluating different crack size and pinion’s displacement, from results could be seen influence of the friction in inter tooth from crack. At the same time [7], did dynamic investigation of cracked gear systems. The whole research was directed into 3 major important factors, crack propagation prediction, mesh stiffness calculation and vibration response calculation. For the object, they took three different gears. At work [8] studied model-based gear dynamic analysis and simulation research evaluating cracks propagation level. Results suggested that root mean square indication is a better statistical indicator than Kurtosis indicator to reflect the crack propagation in the early stages. The article examines the system “Electric Motor-Gearbox-Device” and its rotation vibrations. There are gaps between the teeth and one tooth has a defect. Defect estimated gear tooth stiffness reduction. The deformation of each tooth is assessed.

2 Mathematical Model of Transmission 2.1

The Scope of Calculations and Numerical Characteristics of an Adhesive Joint

A mathematical model of transmission system is considered (Fig. 1). Transmission system which includes asynchronous electric motor, gearbox and connection shafts. Electric motor main parameter are the moment of inertia I1, rotation angle u1, torque Meng. Gearbox includes two connected gear pairs, where the moment of inertia is evaluated I2, I3, I4, I5 rotational angles u2, u3, u4, u5 and Pitch gear radius R2, R3, R4, R5. Transmission system is loaded with constant resistance torque.

Fig. 1. Transmission system dynamic model.

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To evaluate the rotation of the transmission elements, a mathematical model suggested by Bogdevičius [9] may be used: _ eng þ dv Meng ¼ cv ðx0  u_ 1 Þ; M

ð1Þ

where Meng is the torque of the asynchronous electric motor; dv , cv are the parameters of the electric motor; x0 is an angular velocity of idle running; u_ 1 is an angular velocity of electric motor System of equations of rotating shaft has been considered applying the finite element method, € e g þ ½Ce fu_ e g þ ½Ke fue g ¼ fFe g; ½Me fu

ð2Þ

€ e g, where ½Me , ½Ce , ½Ke  are mass, damping and stiffness matrices, respectively; fu fu_ e g, fue g are acceleration, velocity, displacement vectors, respectively; fFe g is external torques vector. The dynamics of k gear i tooth is described below: € k ¼ Mk;trans  Ik u

nzk X

ðkki Rk ðRk uk  qki Þ þ cki Rk ðRk u_ k  q_ ki ÞÞ;

ð3Þ

i¼1

mki €qki ¼ kki ðRk uk  qki Þ þ cki ðRk u_ k  q_ ki Þ þ Fki;lj smesh;ki;lj ;

ð4Þ

where Ik is inertia moment; Mk;trans is k-th torque; mki is k-th gear i-th tooth mass, nzk is the number of gear teeth’s; Fki;lj is contact force between k-th gear i-th tooth and l-th gear j-th tooth; smesh;ki;lj is parameter (smesh;ki;lj ¼ 1 is contact between teeth, otherwise smesh;ki;lj ¼ 0). Contact force Fki;lj is determined by using Hertz’s theory.

3 Initial Data of Research The purpose of the research is to determine the dynamic characteristics (velocity and acceleration) by the effect size of the crack (50% defect) and of whole width on tooth’s surface with 100 lm gap between gear teeth’s. Initial conditions of the variables: at the initial time, the torque of the asynchronous electro engine, transmission systems angle of transmissionnand angular velocity vectors o are equal: (Meng ðt ¼ 0Þ ¼ Meng0 ; fuðt ¼ 0Þg ¼ fu0 g;

duðt¼0Þ dt

¼ fw0 g). External

resistance torque is equal 10 Nm. Gear 1 and gear 3 number of teeth‘s nz ¼ 30, gear 2 and gear 4nz ¼ 20. Integration time step is Dt ¼ 106 s. In the Table 1 the data of the transmission system is shown.

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Table 1. Data calculation of transmission system. Definition

Notation

Definition

R2 = 65.5  10−3 m Mass of inertia R3 = 45.5  10−3 m R4 = 65.5  10−3 m R5 = 45.5  10−3 m Poisson’s ratio 0.3 Young’s modulus Stiffness coefficient Gear tooth’s mass m = 50  10−3 kg of teeth’s Shaft shear modulus of rigidity G = 79.3  109 Pa Damping coefficient of teeth’s Shaft diameter Shaft density q ¼ 7; 820 kg=m3 Inner Radius of the gear

Shaft parameter 1

−4

a = 1  10

Shaft parameter 2

Notation I2 = 50  10−3 kg m2 I3 = 40  10−3 kg∙m2 I4 = 50  10−3 kg∙m2 I5 = 40  10−3 kg∙m2 E = 210  109 Pa ki = 150  106 N/m ci = 1.0  10−2 Ns/m dmax = 50  10−3 m b = 1  10−3

4 Results and Discussion of Transmission System Dynamical characteristics of the transmission system may alter due to defects in gear tooth. The developed model allows a detailed analysis of dynamic characteristic of transmission system. Asynchronous electro engine torque and its first derivative by time dependencies in time are shown in Fig. 2 when defect size is 50% of tooth width and gap between two connected gears 100 lm. Due to the existing gaps between the gear teeth and the current defect, the electrical motor torque is variable in the outgoing process (Fig. 2c). In Figs. 3 and 4 it can be seen transmission process that stay at 1.2 s. Angular velocity of gear 1 reaches 314 rad/s and angular velocity of gear 2 is 454 rad/s. Angular accelerations of gear 1 and gear 2 are variable. Amplitude angular acceleration of gear 1 is about 400 rad/s/s and gear 2 is about 200 rad/s/s. Velocities of 1st (damaged tooth) and 2-nd tooth of gear 1 dependencies in time are shown in Fig. 5. The 1st tooth velocity when it is in contact with another gear tooth is greater than the 2-nd tooth that is not damaged (Fig. 5). In Fig. 6 the angular acceleration dependencies of frequency of gear 1 and gear 2 are presented. The maximum amplitude of angular acceleration of the first gear is 105 rad/s/s and the amplitude of angular acceleration of the second gear is 72 rad/s/s when frequency is 7,700 Hz. In Fig. 7 the acceleration dependencies of frequency of 1-st and 2-nd tooth of gear 1 are presented. The maximum amplitude of acceleration of the first tooth is 740 m/s/s when frequency is about 4,200 Hz and the amplitude of acceleration of the second

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Fig. 2. Asynchronous electro engine torque and first derivative of torque by time: (a) torque; (b), (c) first derivative of torque by time.

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Fig. 3. Angular velocity of driving gear and accelerations of driving gear and driven gear dependencies in time.

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Fig. 4. Angular velocity of driven gear and differences in angular accelerations of driving gear and driven gear dependencies in time.

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Fig. 5. Velocities 1-st and 2-nd tooth of gear 1 dependencies in time.

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Fig. 6. Angular acceleration dependencies of frequency of gears: (a) gear 1; (b) gear 2.

tooth is 480 m/s/s when frequency is about 6,100 Hz. The amplitude of acceleration of damaged tooth is 1,542 times greater than that of not damaged teeth. The decrease in the first tooth stiffness decreased oscillation frequency. This analysis makes it possible to determine which gear has the defect. A more detailed spectrum analysis can be used to determine which gear tooth is damaged.

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Fig. 7. Acceleration dependencies of frequency 1 and 2 tooth of gears 1: (a) tooth 1; (b) tooth 2; (c) tooth 1 and tooth 2.

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5 Conclusions Mathematic model of transmission system with damaged gear tooth is established that allows to analyze rotation processes with different size of the defect on gear tooth and backlash of gears. The resonance frequency changes to a different size of defect. Within 50% of the defect of tooth’s and backlash of gears is 100 lm, angular velocity of gear 1 reaches 310.5 rad/s and angular velocity of gear 2 is 474 rad/s. The maximum amplitude of angular acceleration of the first gear is 105 rad/s/s and the amplitude of angular acceleration of the second gear is 72 rad/s/s when frequency is 7,700 Hz. The maximum amplitude of acceleration of the first tooth is 740 m/s/s when frequency is about 4,200 Hz and the amplitude of acceleration of the second tooth is 480 m/s/s when frequency is about 6,100 Hz. The amplitude of acceleration of damaged tooth is 1,542 times greater than that of not damaged teeth. With the transmission rotational movement analysis, it is possible to determine the gear wheel gear teeth damage.

References 1. Parker, R.G., Agashe, V., Vijayakar, S.M.: Dynamic response of a planetary gear system using a finite element/contact mechanics model. J. Mech. Des. 122, 304–310 (1991) 2. Prueter, P.E., Parker, R.G.: Cunliffe, F.: A study of gear root strains in a multi-stage planetary wind turbine gear train using a three-dimensional finite element/contact mechanics model and experiments. In: Proceedings of the Design Engineering Technical Conference, pp. 621–633 (2011) 3. Lin, T., Ou, H., Li, R.: A finite element method for 3D static and dynamic contact/impact analysis of gear drives. Comput. Methods Appl. Mech. Eng. 197, 1716–1728 (2007) 4. Xue, S., Entwistle, R., Mazhar, I., Howard, I.: The torsional stiffness of involute spurs planetary gears. In: Proceedings of the 9th IFToMM International Conference on Rotor Dynamics, vol. 21 (2015) 5. Walha, L., Fakhfakh, T., Haddar, M.: Nonlinear dynamics of a two-stage gear system with mesh stiffness fluctuation, bearing flexibility and backlash. Mech. Mach. Theor. 44, 1058– 1069 (2009) 6. Mohammed, O.D., Rantatalo, M., Aidanpἂἂ, J.O.: Dynamic modelling of a one-stage spur gear system and vibration-based tooth crack detection analysis. Mech. Syst. Signal Process. 54–55, 293–305 (2015) 7. Ma, H., Zeng, J., Feng, R., et al.: Review on dynamics of cracked gear systems. Eng. Fail. Anal. 55, 224–245 (2015) 8. Tain, Z., Zuo, M.J., Wu, S.: Crack propagation assessment for spur gears using model-based analysis and simulation. J. Intell. Manuf. 23, 239–253 (2012) 9. Aladjev, V., Bogdevičius, M.: Maple: Programming, Physical and Engineering Problems. Fultus Publishing, Palo Alto (2006)

Application of Virtual Prototype to Heavy-Duty Gearbox Housing Evaluation Kamil Rehak(&)

, Pavel Kucera

, and Ales Prokop

Brno University of Technology, Technicka 2, Brno, Czech Republic {rehak,kucera,prokop.a}@fme.vutbr.cz

Abstract. This paper deals with application of methodology for design of gearbox and its validation by technical experiment. First, the methodology for gearbox was developed and validated on the small single-stage gearbox concept, which enables simple modifiability. The methodology can be divided into three different level (modal analysis, harmonic analysis and multibody simulation). The outputs from previous model increase accuracy of next level of model. Each step of methodology was validated by partial experiment. The sensitivity of input parameters is investigated afterwards to see the limits of methodology. The methodology is applied on a heavy-duty gearbox concept afterward, where all inputs parameters are calculated in similar way as in case of small single-stage gearbox. A partial experimental approach to validate the application of virtual prototype on very complex and extremely loaded component were performed. Based on the results from numerical approach and their comparison to the measurement, the virtual prototype is powerful tool, which can be used in designing phase or in case of optimization. Keywords: Gearbox


Noise
Vibration
Numerical approach

1 Introduction Gearboxes are widely used in industrial, civilian and military application. The operation conditions are very different based on the application. The principle is still the same, where gears are used to provide speed and torque conversions from a rotating power source to another device. In cases where the engine is used as power source, it is in most cases primary source of noise and vibration. For that reason, the methodology with using numerical approach for powertrain was developed to predict noise and vibration with dominant focus on engine [1, 2]. With an increasing interest in electromobility, gearboxes become one of the dominant sources of noise and vibration. With the increasing standard and demands on transport means, the passenger’s comfort is solved also in public transport. The passenger’s comfort is solved from the point of view of the environment itself (ergonomics, riding comfort, thermal comfort), but also a part of transmission system has to be considered (vibration and noise). In case of modern high-speed trains, which are becoming popular for their speed, safety, and reduction of traffic jam dependence, the vibroacoustic behavior of high-speed gearbox has to be solved. It is also necessary to consider the limits of current technologies [3]. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 361–368, 2020. https://doi.org/10.1007/978-3-030-38666-5_38

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The individual components of gearbox must fulfil the requirements for resistance to mechanical loads. However, in the event of an inappropriate change in stiffness, only one of the components may overload another unit, thus the designing of individual components separately (without considering interactivity) cannot be used. For that reason, new methods had to be developed to match the components together with the design itself, allowing optimization in terms of weight and stiffness, including subsequent effects on acoustics and vibrations. Wide range of different approaches is used based on the type of solving problem [4, 5]. First the stress-strain analysis of each component as well as the whole assembly has to be performed to check if the requirements for resistance to mechanical loads are fulfilled. Further the dynamic analysis, which can be divided into three different levels of method to solve noise, vibration, and harshness (NVH), can be performed. The validation is a very important step for each level of model. For that reason, the whole methodology was created on single stage gearbox, which was designed with respect of simple modifiability. 1.1

Creation of Methodology on Single Stage Gearbox

Any methodology without proper and sufficient validation by the experiment cannot be implemented to the real application. For that reason, the single stage gearbox with respect to perform corresponding experiment from the dynamic behavior point of view was designed and manufactured [6]. The single stage gearbox is widely used for examination of oil behavior, the influence of contact behavior, unbalance, backlash, torque value and transmission error [7–9]. Presented approach combines Finite Element Methods (FEM), Multi-Body System (MBS). The whole methodology can be divided into three levels of model – modal analysis, harmonic analysis and multibody simulation. Each model level of used methodology was performed by numerical approach and validated by technical experiment. The results from experiment and numerical approach were compared, and the inputs were refined until a match has been reached. In the case of geometry, the reverse engineering method was also used. After validation of methodology, the sensitivity studies were performed. More details about the sensitivity studies of input variable, tooth damage, rattle phenomenon are available in articles [10–13]. The presented methodology was also used for heavy-duty vehicle application [14].

2 Methods 2.1

Modal Analysis

To achieve adequate results of noise and vibration from numerical simulation the accurate modal properties of all component are very important. The accuracy can be determined based on the comparison to results from technical experiment. To get good match several modal analyses have to be performed. First, the CAD data can be used. Because the housing is manufactured by casting, the tolerances have to be taken into account. The methods for reverse engineering can increase the accuracy from geometry point of view. The material parameters have to be also verified. The numerical simulation should respect boundary conditions of technical experiment.

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Modal analysis was performed with free boundary conditions for all components. The grid for technical experiment, where the response or excitation is applied, should respect the frequency range of investigation, see Fig. 1. The excitation of structure is performed by modal hammer and the response is recorded by triaxial accelerometer or laser vibrometer. After inputs refining the eigen frequency difference between numerical and experimental results is up to 3.5%, which is at lowest eigen frequency. With increasing frequency the difference is below 2%.

Fig. 1. (a) Modal analysis of heavy-duty gearbox housing, comparison of modal shape from (b) numerical approach and (c) experiment.

The eigen frequency and corresponding modal shape were compared for both approaches, see Fig. 1. With increasing of geometry model accuracy, the difference between approaches is decreasing. The model from reverse engineering improves dominantly higher frequency range, but this area is also necessary from the acoustic point of view. 2.2

Harmonic Analysis

The modal analysis outputs were used to increase the accuracy of structure dynamic behavior description on the harmonic force excitation on which is the harmonic analysis based. The simulation used same boundary conditions as the technical experiment for each component, including force, for that reason the technical experiment has to be performed first.

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Fig. 2. Evaluation of (a) structure response, (b) acoustic response in time and frequency domain, (c) harmonic analysis of heavy-duty gearbox housing performed in full anechoic chamber.

The harmonic analysis was performed for each component of the gearbox in the fully anechoic chamber because the measurement by microphones was included, see Fig. 2. For that reason, the modal exciter was covered by encapsulation. The excitation for both approaches was applied to the same location (bearings). The force sensor was placed on the rod, which connect modal exciter and measured component, to record the force, which is necessary for numerical simulation to be comparable. The accelerometer/laser vibrometer were used to record the structure response in places, which were determined based on results from modal analysis for given frequency. The response at sweep and steady state cases was investigated. The acoustic response at given frequency were investigated based on the data from microphone and acoustic pressure distribution. After inputs refining the difference between numerical and experimental results are up to 20%. The surface normal velocity, which is very sensitive to damping value, is

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shown in Fig. 3. Without correct distribution of surface normal velocity the sound pressure level in given location takes big differences in comparison to data from experiment.

Fig. 3. Numerical harmonic analysis of heavy-duty gearbox housing, (a) surface normal velocity, (b) sound pressure level distribution in transversal plane, (c) longitudinal plane, (d) sound pressure level in given location.

2.3

Transmission Error

The design of the geometry of gearing and the accuracy of its production is strongly influenced by the excitation under individual load conditions. This can be evaluated based on the transmission error (TE). The TE can be calculated by using (1). In presented article, the computational approach by using ADAMS Gear, Ansys, and KissSoft has been used. TE ¼ ðu2 

z2 u Þr2 ; z1 1

ð1Þ

where u1 is the gear pinion rotation angle; u2 is the gear rotation angle; z1 is the pinion teeth number; z2 is the driven gear teeth number; r2 is the gear pith circle radius.

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Two encoders ERN 460 were used in the measuring loop – on the input and output shaft of the analyzed transmission gear. The used encoder has two outputs, which have offset signals and each output signal allows generating 3,600 pulses per revolution, which describe the behavior very accurately. The measurement process was performed for different value of torque to find the best operation conditions of given gearbox. The measurement was focused on the static transmission error; thus, the value of input shaft speed was set very low. The transmitted torque and input speed were controlled by the control system. The measured data for each different operation condition is shown in Fig. 4.

Fig. 4. (a) TE during one turn of pinion, (b) TE median during one turn for different loading moment.

2.4

Multibody Simulation

The highest level of modelling of the transmission dynamics behavior is based on the multi-body modelling. For this case the commercial software ADAMS is used. The simulation is solved in time domain. The virtual prototype incorporates most of phenomenon and features, which are typical for the real transmission dynamic behavior. The modal properties are incorporated by means of Craig-Bampton modal reduction, which is applied to the gearbox housing, shafts and gears. The tooth contact is precalculated by FEM and is represented by stiffness-damping function, which has nonlinear character. This functionality is solved in the special software module Gear AT, where the all microgeometry parameters are taken into account. The backlash influence, which is very important for the loading states with the low-level of the carried torque, is included in the simulation. Connection between the shafts and housing is provided by non-linear stiffness-damping function for each direction. The gearbox boundary conditions are respecting the test-rig conception. This means, that the output shaft is

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constrained trough the two additional bearings to the test room base, thus the whole gearbox assembly can perform rotation around the wheel axle. For this reason, the reaction forces have to be eliminated by the reaction rod. The whole computational model is shown in Fig. 5. With respect to the real loading conditions, the input speed and loading torque can be applied on the shafts. The main advantage of the whole complex virtual prototype is, that the model is defined using the parametric script command, thus the sensitivity study can be performed with the goal to investigate the influence of the key parameters.

Fig. 5. Virtual prototype of heavy-duty gearbox.

3 Conclusion The presented approach was developed on the single stage gearbox. Each part of method was validated by technical experiment to increase the accuracy of prediction by numerical simulation. Wide range of measurement equipment, refining methods and numerical simulation have been used to reach corresponding results from both approaches. The methodology was used for heavy-duty gearbox afterwards. The results from modal analysis of heavy-duty gearbox correspond to each other very well. The difference of surface normal velocity at harmonic analysis is up to 20%. The difference is high, because of relatively small value of vibration, but there could be some inaccuracy of technical experiment, thus the measuring assembly should be modified and tested to increase accuracy. The virtual prototype of gearbox is compared to the test rig, where other components are presented, thus it should be extended by surroundings component to be more complex. Based on the presented results the methodology can be useful at designing or optimization phase, but the methodology is still under development, so it is necessary to validate the final product by technical experiment. Acknowledgment. The research leading to these results has received funding from the project FSI-S-17-4104 granted by specific university research of Brno University of Technology and project TH02010725 granted by Technology Agency of the Czech Republic. The authors gratefully acknowledge this support.

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References 1. Gold, P., Schelenz, R., Pischinger, S.: Acoustical investigation on the engine – transmission interaction. MTZ 12, 2013 (2013) 2. Novotny, P., Prokop, A., Zubik, M., Rehak, K.: Investigating the influence of computational model complexity on noise and vibration modeling of powertrain. J. Vibroeng. 18(1), 378– 393 (2016). ISSN 1392-8716 3. Wu, H., Wu, P., Li, F., Shi, H., Xu, K.: Fatigue analysis of the gearbox housing in highspeed trains under wheel polygonization using a multibody dynamics algorithm. Eng. Fail. Anal. 100, 351–364 (2019) 4. Liang, X., Zuo, M.J., Feng, Z.: Dynamic modeling of gearbox faults: a review. Mech. Syst. Sig. Process. 98, 852–876 (2018). ISSN 0888-3270 5. Hu, W., Liu, Z., Liu, D., Hai, X.: Fatigue failure analysis of high speed train gearbox housings. Eng. Fail. Anal. 73(2017), 57–71 (2017) 6. Prokop, A., Rehak, K., Zubik, M., Novotny, P.: Investigation of single stage gearbox parameters influencing surface normal velocity. In: Engineering Mechanics 2016, pp. 478– 481 (2016). ISBN 978-80-87012-59-8 7. Razpotnik, M., Bischof, T., Boltezar, M.: The influence of bearing stiffness on the vibration properties of statically overdetermined gearboxes. J. Sound Vib. 351, 221–235 (2015) 8. Ma, R., Chen, Y., Cao, Q.: Research on dynamics and fault mechanism of spur gear pair with spalling defect. J. Sound Vib. 331(9), 2097–2109 (2012) 9. Loutas, T., Sotiriades, G., Kalaitzoglou, I., Kostopoulos, V.: Condition monitoring of a single-stage gearbox with artificially induced gear cracks utilizing on-line vibration and acoustic emission measurements. Appl. Acoust. 70(9), 1148–1159 (2009) 10. Prokop, A., Kopeckova, B., Rehak, K.: Dynamic analysis of single stage gearbox focused on input parameters influence. In: Transport Means 2017. Transport Means. Kaunas Lithuania, pp. 479–484 (2017). ISSN 1822-296X 11. Rehak, K., Prokop, A., Zubik, M.: Comparison of torque influence on single stage gearbox vibrations. In: KOKA 2016. Brno, pp. 173–178 (2016). ISBN 978-80-214-5379-1 12. Rehak, K., Prokop, A.: Numerical simulation of single stage gearbox with tooth damage. In: Vibroengineering PROCEDIA. Vibroengineering Procedia, pp. 88–92. JVE International Ltd., Kaunas (2016). ISSN 2345-0533 13. Prokop, A., Kopeckova, B., Rehak, K.: Gear drive system simulation of input parameters effect on rattle. In: Acoustics and Vibration of Mechanical Structures. Springer Proceedings in Physics, pp. 381–388 (2017). ISBN: 9783319698236. ISSN: 0930-8989 14. Prokop, A., Rehak, K.: Virtual prototype application to heavy-duty vehicle gearbox concept. In: Engineering Mechanics 2017, pp. 810–813 (2017). ISBN 978-80-214-5497-2

Modeling of Diesel Engine Energy Efficiency Parameters and Evaluation of Different Combustion Models Linas Jonika1(&), Sergėjus Lebedevas2, and Vygintas Daukšys2 1

Marine Research Institute, Waterborne Transport and Air Pollution Laboratory, Klaipeda University, Universiteto alley 17, 92294 Klaipėda, Lithuania [email protected] 2 Klaipeda University, Bijūnų str. 17, 91225 Klaipėda, Lithuania [email protected]

Abstract. This publication contains results of indicated diesel engine cycle parameters modelled using mathematical modeling AVL FIRE software. Purpose of research was to evaluate different combustion model adequacy to model indicated diesel engine cycle parameters. In order to achieve this purpose mathematical modeling was conducted using Eddy Breakup, Extended Coherent Flame-3Z, Characteristic Timescale models. Most accurate results were obtained using the Extended Coherent Flame-3Z model. At high engine load mode (HLM) this model had an error for the indicated mean effective pressure of 8%, for the indicated efficiency 10%, for the maximum cylinder pressure 8% and the difference in ignition delay was 2 CAD, however it did not perform well at low engine load mode (LLM) and had an error of 21% for indicated mean effective pressure, 19% for the indicated efficiency, 2% in the maximum cylinder pressure and the difference in ignition delay was 1 CAD. For the Characteristic Timescale and Eddy Breakup models the errors for indicated mean effective pressure were 13% and 14% in HLM and 16% and 13% in LLM respectively. One possible explanation for large errors in mathematical models is the difference in ignition delay between the experiment and mathematical models. The Characteristic Timescale and Eddy Breakup models had a difference in ignition delay of 4.5 CAD and 3.5 CAD respectively at HLM and 3.5 CAD at LLM. Keywords: Mathematical modeling characteristics
Induction period


Diesel engine cycle
Heat release

1 Introduction Together with widely conducted experimental internal combustion engine (ICE) technology research [1–3], no smaller focus is given to the development of mathematical modelling technologies [4–6]. Among the numerical models used, the priority is given to multi-zone models, applied in software products: FIRE (AVL, Austria), KIVA (Energy research center laboratory, USA) and VECTIS (Ricardo, UK), etc. [7–9]. One of the most prominent research directions into ICE technologies is related to new dual-fuel engine design and currently operational diesel engine conversion for © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 369–376, 2020. https://doi.org/10.1007/978-3-030-38666-5_39

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operation on LNG and CNG. Namely, one of the main practical applications of multizone mathematical models is related to the wide possibilities that enable investigation on fast acting physical energy transfer and harmful component emission formation processes in engine cylinder. Precisely optimization of these parameters makes up the basis for energy efficiency increase and harmful emission control in engines operating on natural gas [10–17]. This publication contains aspects of research conducted in Klaipeda University into converted for operation on dual diesel and compressed natural gas fuel engine technologies, which have an objective to apply different AVL FIRE software mathematical combustion models for indicated dual-fuel engine cycle energy efficiency and emission research.

2 Experiment Methodology “AVL FIRE” was used for numerical research, which is a computational fluid dynamics simulation package designed to simulate both physical and chemical processes in the internal combustion engine. Because energy efficiency parameters in a large part are influenced by correct combustion and induction period modeling the main focus of research is synchronization of mathematical models with the experiment. “AVL FIRE” allows the user to calculate species transport, mixing of homogeneous and heterogeneous fuel mixtures, as well as ignition and turbulent combustion in compression and spark ignition internal combustion engines. For the numerical research three different combustion models were used: Eddy Breakup Model, Extended Coherent Flame-3Z (ECFM-3Z) Model and the Characteristic Timescale Model. Model descriptions were taken from the FIRE VERSION 2014 manual [18]. 2.1

Description of Combustion Models Used

Eddy Breakup Model. Eddy Breakup Model is based on eddy dissipation concept, which assumes that the mean turbulent reaction rate is determined by the intermixing of cold reactants with hot combustion products. It is possible to use the Eddy Breakup Model when modeling a diesel ignited gas engine. Extended Coherent Flame-3Z Model. ECFM-3Z model was developed for diesel combustion. This is a combustion model based on a flame surface density transport equation and a mixing model that can describe inhomogeneous turbulent premixed and diffusion combustion. Characteristic Timescale Model. Characteristic Timescale Model takes into account a laminar and a turbulent time scale. The laminar time scale considers the slower chemical reaction rates especially at the beginning of the combustion. The turbulent time scale gives the influence of the turbulent motion to the reaction rate.

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371

Research Object

Research object was a converted for operation on dual diesel and compressed natural gas fuel high revolutions four-stroke diesel engine with a conventional fuel injection system. Engine used was a direct injection diesel engine 4-cylinder engine 79.5/95 with electronic controlled BOSCH VP37 distribution type fuel pump and turbocharger. The main parameters of the diesel engine Audi 1.9 TDI are shown in Table 1. Table 1. Engine specification. Model Displacement, (cm3) Bore  Stroke, (mm) Maximum power, (kW/rpm) Maximum torque, (Nm/rpm) Cooling type Fuel supply system Cylinders Compression ratio Aspiration

VW-Audi 1Z 1.9 TDI 1,896 79.5  95.5 66/4,000 180/2,000–2,500 Water cooling Direct injection 4 in line 19.5:1 Turbocharge

Fuel used for the experiment was standard diesel fuel (EN 590). Fuel properties are provided in Table 2. Table 2. Fuel properties. Fuel type Density (kg/m3) Cetane number Heat value (MJ/kg) Viscosity (cSt 40 °C) H/C ratio

Diesel (EN 590) 829.0 49 42.8 1.485 1.907

Engine speed and fuel injection timing were kept constant throughout experiment and numerical modelling at 2,000 rev/min and 13 CAD respectively. With respect to the purpose of this research, diesel engine thermal cycle indicated process diagrams were analyzed for two different engine load modes: high load mode (HLM) at an indicated mean effective pressure of 8.2 bar and low load mode (LLM) at indicated mean effective pressure of 4.42 bar.

3 Experiment Results and Discussion Heat release characteristic graphs for different engine load modes in differential and integral forms are provided in Fig. 1.

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CAD Experiment Eddy Breakup CharacterisƟc Timescale

c)

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Fig. 1. (a) accumulated heat release (AHR) at HLM; (b) rate of heat release (RHR) at HLM; (c) accumulated heat release (AHR) at LLM; (d) rate of heat release (RHR) at LLM.

From the graphs in Fig. 1 it can be concluded that energy efficiency parameters are highly influenced by the crank angle degree (CAD) at which auto-ignition of diesel fuel begins. As it can be seen from Fig. 1a at HLM the auto-ignition angle for two models is about 4 CAD earlier when compared to the experiment, this could result in different reaction rates throughout the combustion phase. As it can be seen in Fig. 1b the rate of heat release for both numerical models remain more stable throughout the combustion phase and only reach a maximum rate of heat release of 25 J/CAD, however rate of

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heat release of the experiment has a larger rate of heat release of 37 J/CAD at the beginning of the combustion phase. One reason for a smaller RHR is a longer ignition delay in the experiment and this means that statistical data for the models that were used must be supplemented with experimental data in order to adjust the induction period. At LLM the rate of heat release diagram for the experiment differs significantly for both combustion models. The angle of auto-ignition for combustion models is 4 CAD earlier when compared to the experiment. The rate of heat release for LLM is similar to rate of heat release of HLM. As it can be seen from Fig. 1d the rate of heat release from experiment has a maximum of 32 J/CAD, characteristic flame and eddy breakup models have 21 J/CAD and 25 J/CAD respectively. Graphical representations of AHR and RHR values for the Extended Coherent Flame 3Z model are not provided in this publication, although indicated engine cycle process values fit well with the experimental data, within a reasonable error. Indicated cylinder pressure diagrams from experimental data and different “AVL FIRE” combustion models are shown in Fig. 2.

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Experiment Eddy Breakup CharacterisƟc Timescale Extended Coherent Flame 3Z Pmax experiment Pmax Eddy Breakup Pmax CharacterisƟc Timescale Pmax Extended Coherent Flame 3Z TDC

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Fig. 2. Indicated mean cylinder pressure diagrams. (a) HLM; (b) LLM.

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At HLM the indicated maximum cylinder pressure for Eddy Breakup, Characteristic Timescale Extended and Coherent Flame-3Z models was 92, 90.5 and 97.8 bar respectively and at LLM 93, 91, and 81.7 bar respectively. Mathematical modelling and experimental data are provided in Table 3. Table 3. Comparison of indicated engine cycle process parameters from experimental data and different “AVL FIRE” combustion models. HLM Experiment Characteristic flame model Indicated mean effective pressure Pmi , bar Indicated efficiency gi , % Auto-ignition angle, CA Maximum cylinder pressure Pmax , bar Air excess ratio a

Indicated mean effective pressure Pmi , bar Indicated efficiency gi , % Auto-ignition angle, CA Maximum cylinder pressure Pmax , bar Air excess ratio a

Extended coherent flame Model-3Z

8.2

7.16/87%

Eddy breakup model 7.07/86%

0.51 714 105.8

0.44/86% 709.5 92/87%

0.43/84% 710.5 90.5/86%

0.46/90% 716 97.8/92%

2.53/87%

2.53/87% Extended coherent flame Model-3Z 3.49/79%

2.92 2.53/87% LLM Experiment Characteristic flame model

7.54/92%

4.42

3.94/89%

Eddy breakup model 4.07/92%

0.559 716 80.3

0.5/89% 709.5 93/116%

0.52/93% 709.5 91/113%

0.45/81% 717 81.7/102%

5.22

5.47/105%

5.47/105%

5.47/105%

It was established that best performing model was Extended Coherent Flame Model-3Z. Pmax error for this model was 8% at HLM and 2% at LLM. Indicated cylinder pressure diagrams fit well with experimental pressure diagrams, Pmi error was 8% at HLM and 21% at LLM, gi , error was 10% at HLM and 19% at LLM. Difference in ignition delay was 2 CAD at HLM and 1 CAD at LLM.

4 Conclusions Numerical research was conducted using AVL FIRE software fuel combustion Characteristic flame, Eddy breakup and Extended Coherent Flame 3Z models by applying them to diesel engine HCN 79.5/95 indicated process characteristics research.

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• Best results were achieved using the Extended Coherent Flame model-3Z which had an error of 8% for mean effective pressure, 10% for indicated efficiency, 8% for maximum cylinder pressure and difference in ignition delay was 2 CAD at HLM. However, this model did not perform well at LLM and had an error of 21% for the mean effective pressure, 19% for indicated efficiency, 2% for maximum cylinder pressure and a difference of 1 CAD in ignition delay. • It should be noted that fuel combustion mathematical model adequacy is significantly influenced by a correct ignition delay. • When the Characteristic flame and Eddy breakup models were used at HLM the error for indicated mean effective pressure was 13 and 14% respectively, indicated efficiency 14%, indicated maximum cylinder pressure 13 and 14% and difference in ignition delay 4.5 and 3.5 CAD. At LLM the error for indicated mean effective pressure was 11 and 8% respectively, indicated efficiency 11 and 7%, indicated maximum cylinder pressure 16 and 13% and difference in ignition delay 6.5 CAD. By referring to obtained results it is planned to supplement AVL FIRE combustion model data with data obtained from the experiment. Acknowledgments. The authors are grateful to AVL Advanced Simulation Technologies for providing the AVL FIRE simulation software. AVL FIRE was acquired by signing the Cooperation Agreement between AVL Advanced Simulation Technologies and the Faculty of Marine Technologies and Natural Sciences of Klaipeda University.

References 1. Yin, L., Lundgren, M., Wang, Z., Stamatoglou, P., Richter, M., Andersson, Ö., Tunestål, P.: High efficient internal combustion engine using partially premixed combustion with multiple injections. Appl. Energy 233–234, 516–523 (2019) 2. Reitz, R., Duraisamy, G.: Review of high efficiency and clean reactivity controlled compression ignition (RCCI) combustion in internal combustion engines. Prog. Energy Combust. Sci. 46, 12–71 (2015) 3. Ambrós, W., Lanzanova, T., Fagundez, J., Sari, R., Pinheiro, D., Martins, M., Salau, N.: Experimental analysis and modeling of internal combustion engine operating with wet ethanol. Fuel 158, 270–278 (2015) 4. Li, J., Yang, W., An, H., Chou, S.: Modeling on blend gasoline/diesel fuel combustion in a direct injection diesel engine. Appl. Energy 160, 777–783 (2015) 5. Benajes, J., Novella, R., Pastor, J., Hernández-López, A., Hasegawa, M., Tsuji, N., Emi, M., Uehara, I., Martorell, J., Alonso, M.: Optimization of the combustion system of a medium duty direct injection diesel engine by combining CFD modeling with experimental validation. Energy Convers. Manag. 110, 212–229 (2016) 6. Poorghasemi, K., Saray, R., Ansari, E., Irdmousa, B., Shahbakhti, M., Naber, J.: Effect of diesel injection strategies on natural gas/diesel RCCI combustion characteristics in a light duty diesel engine. Appl. Energy 199, 430–446 (2017) 7. Yang, Z., Chu, C., Wang, L., Huang, Y.: Effects of H2 addition on combustion and exhaust emissions in a diesel engine. Fuel 139, 190–197 (2015)

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8. Zehni, A., Saray, R.: Comparison of late PCCI combustion, performance and emissions of diesel engine for B20 and B100 fuels by KIVA-CHEMKIN coupling. Renewable Energy 122, 118–130 (2018) 9. Divis, M., Tiney, N., Lucas, G.: Spray modeling of multicomponent fuels in industrial time frames using 3D CFD. In: Proceedings, pp. 132–152 (2017) 10. Nithyanandan, K., Lin, Y., Donahue, R., Meng, X., Zhang, J., Lee, C.: Characterization of soot from diesel-CNG dual-fuel combustion in a CI engine. Fuel 184, 145–152 (2016) 11. Mousavi, S., Saray, R., Poorghasemi, K., Maghbouli, A.: A numerical investigation on combustion and emission characteristics of a dual fuel engine at part load condition. Fuel 166, 309–319 (2016) 12. Sahoo, B., Sahoo, N., Saha, U.: Effect of engine parameters and type of gaseous fuel on the performance of dual-fuel gas diesel engines—a critical review. Renew. Sustain. Energy Rev. 13, 1151–1184 (2009) 13. Hosmath, R., Banapurmath, N., Khandal, S., Gaitonde, V., Basavarajappa, Y., Yaliwal, V.: Effect of compression ratio, CNG flow rate and injection timing on the performance of dual fuel engine operated on honge oil methyl ester (HOME) and compressed natural gas (CNG). Renewable Energy 93, 579–590 (2016) 14. Li, W., Liu, Z., Wang, Z.: Experimental and theoretical analysis of the combustion process at low loads of a diesel natural gas dual-fuel engine. Energy 94, 728–741 (2016) 15. Guo, H., Neill, W., Liko, B.: An experimental investigation on the combustion and emissions performance of a natural gas–diesel dual fuel engine at low and medium loads. In: Volume 1: Large Bore Engines; Fuels; Advanced Combustion (2015) 16. García Valladolid, P., Tunestål, P., Monsalve-Serrano, J., García, A., Hyvönen, J.: Impact of diesel pilot distribution on the ignition process of a dual fuel medium speed marine engine. Energy Convers. Manag. 149, 192–205 (2017) 17. Maurya, R., Mishra, P.: Parametric investigation on combustion and emissions characteristics of a dual fuel (natural gas port injection and diesel pilot injection) engine using 0-D SRM and 3D CFD approach. Fuel 210, 900–913 (2017) 18. FIRE VERSION (2014). https://web.itu.edu.tr/*sorusbay/SI/AVL2.pdf. Accessed 25 Feb 2019

On the Issue of Wheel Flange Sliding Along the Rail Evgeny Mikhailov1(&) , Stanislav Semenov1 , Svitlana Sapronova2 , and Viktor Tkachenko2 1 Volodymyr Dahl East Ukrainian National University, Central Avenue, 59A/403, 93405 Severodonetsk, Ukraine [email protected], [email protected] 2 State University of Infrastructure and Technology, Kirilivska str., 9/3, 04080 Kiev, Ukraine [email protected], [email protected]

Abstract. Rail transport performs significant volumes of transportation work and is one of the largest energy consumers in all developed countries of the world. Most of the energy used in railway transport is spent on train traction. To improve its energy efficiency, it is advisable to carry out measures aimed at reducing the resistance to movement of trains. A special contribution to the creation of resistance to the movement of rail vehicles is made by processes associated with the interaction of the wheel flange with the rail in the case of two-point contact, when additional parasitic differential slip occurs in the ridge contact. It is impossible to avoid this slippage without changing the traditional structural scheme of the wheel (with monolithic production of its supporting and guiding surfaces). The work considers the kinematics of the movement of the ridge along the lateral face of the rail head during rolling of the wheel of the rail carriage. An analytical expression is obtained for the approximate determination of the length of the wheel flange slipping path along the lateral face of the rail head, taking into account the conditions of its contact with the rail. The features of the kinematics of the wheels movement of the traditional and perspective (with the possibility of independent rotation of the bearing surface of the wheel and its guide surface) of the design scheme are analyzed. The levels of work of the friction forces in the ridge contacts of the wheels of different design schemes are determined. The results of the analysis suggest that the use of wheels of a perspective design in the undercarriage of rail vehicles can significantly reduce the kinematic resistance to movement and wear of the contacting surfaces of the wheel and rail by reducing the slip of wheel crests along the side faces of the rail heads. Keywords: Wheel


Rail top
Flange
Sliding
Resistance to movement

1 Introduction Rail transport performs significant volumes of transportation work and is one of the largest energy consumers in all developed countries of the world. Most of the energy used in railway transport is spent on train hauling. Considering the relatively high cost © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 377–385, 2020. https://doi.org/10.1007/978-3-030-38666-5_40

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of utilities, reducing their consumption is the most important task for improving competitiveness and further development of this type of transport. It is clear that to improve the energy efficiency of rail transport, it is advisable to implement measures aimed at decreasing the resistance to train motion. The external forces that make up the total resistance to the motion of a train are different in nature and causes of occurrence. Therefore, to develop these measures, their structure and the real possibilities for control the intensity of their effect shall be determined. In general case, apparent impedance to the motion of the carriage in rail transport includes continuous main resistance and temporarily additional resistance (at starting, due to low temperature, wind, slope, curves, air in a tunnel, etc.) [2, 7, 8, 16, 17]. When analyzing the significance of components of resistance to the motion of rail carriages, many researchers have come to the conclusion that the greatest contribution to the total resistance to motion is made by those related to the kinematics and dynamics of the frictional interaction of the wheels and the rail track [4, 8, 11, 12, 18, 20]. Therefore, the most promising areas of research to decrease resistance to motion are works aimed at reducing these components. Processes associated with the interaction of the wheel flange with the rail in the case of two-point contact when an additional idle sliding occurs in the flange contact make a special contribution to the creation of resistance to the motion of rail vehicles. Some researchers state that “the value of specific resistance in the curve of the path attributable to flange friction is about 95% of its total value” [4]. The concept of kinematic resistance to motion was introduced in [11, 12]. It is caused by the kinematic discrepancy between the geometrical parameters of the rolling surfaces of the wheels and the kinematic parameters of motion leading to idle sliding. It was proposed to allocate two components in the kinematic resistance to motion, namely, differential and circulation resistance. The first is determined by the spatial distribution of contact forces and sliding speeds in a wheel-rail pair and the second is the result of group multi-contact interaction of a system of wheels and wheel pairs with a rail in the course of guided motion in a rail track. Directly associated with these phenomena such as increased energy consumption to overcome the additional resistance to the motion of rolling stock as well as the current wear of the contacting surfaces of wheels and rails become a serious technical and economic problem for rail transport. There is a number of ways to reduce energy consumption for train traction and wear of the contacting surfaces. The most developed and widespread of them are the lubrication of the contact areas of wheel with rail, the optimal choice of the ratio of wheel and rail hardness, the selection of conformal sections of wheel and rail surfaces, etc. [5, 8, 13, 19]. However, the use of these technologies allows only partial solving the problem of reducing kinematic resistance. An important direction for solving this problem may be improving the design of the running gears of rail vehicle, which consists of optimization of parameters of the spring suspension, providing a radial layout in the curves of carriages and wheelsets of the vehicle, improving the design schemes of the wheelsets, for example, the use of independently rotating wheels, which is the subject of a sufficiently large number of works, namely, [5, 6, 13, 14]. However, insufficient attention has been paid to the issues of improving the designs of the rail vehicle themselves. Nevertheless, without

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changing the conventional structural design of the wheel (with manufacturing of its monolithic bearing surface and flange), it is impossible to avoid the above-mentioned idle differential slide of the flanges along the rails. Therefore, it is advisable to consider the possible advantages of a fundamental change in the structural design of the wheel, for example, allowing its guide surface (flange) to rotate relative to the bearing surface of the wheel around their common axis (hereinafter, the wheels of the advanced structural design). The authors proposed several options for the design of such wheels for rail vehicles [9, 18]. Without discussing in detail the peculiarities of these structures, it shall be underlined that all of them are aimed at reducing the kinematic resistance to motion during the two-point contact of the wheel with the rail by decreasing the level of flange sliding along the rail top. The purpose of this work is to determine the wheel flange sliding distance along the rail and the possibilities of reducing the kinematic resistance to the motion of the wheel of a rail vehicle due to a change in the structural design of the wheel.

2 Methodology of Researches The wheel motion along the rail can be approximately described by the equations of plane-parallel motion of the body. Thus, any movement of the same in a continuously small period of time can be divided into translation motion at the speed of a certain point of the body and rotational movement around the instantaneous axis passing through this point. Let us consider the case when the wheel rolls along the rail at a constant speed V, the longitudinal sliding at point A of its contact with the rail is missing and the flange attack angle is w = 0. The following assumptions shall be adopted: the wheel flange is pressed against the side edge of the rail top with a constant transverse force F, friction coefficient in the flange contact is l = const, the contact areas of the rolling surface of the wheel and the rail, as well as the wheel flange and the side edge of the rail top are geometric points. The instantaneous center of rotation of any point of the wheel during such a motion is the point of contact of the wheel with the rail A. When the wheel is rolling along the rail without sliding, point A located at the wheel rolling surface moves along the trajectory of ordinary cycloid (Fig. 1), and point B located at the wheel flange follows the trajectory of the elongated cycloid [1, 3]. The trajectory of point B on an elongated cycloid does not have any spinodes. At the same time, there are some “loops” on the trajectory of the elongated cycloid, a part of their perimeter (Fig. 1) falls on the flange sliding distance along the side edge of the rail top. In the case of using an advanced structural design wheel, point B on the wheel flange when it is rolling on the rail can ideally roll along the side edge of the rail top almost without sliding moving along the trajectory of an ordinary cycloid (Fig. 2). The decreasing of idle sliding in the flange contact determines a corresponding reduction in the friction forces impact, which will significantly diminish the differential component of the kinematic resistance to the motion of this wheel.

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Fig. 1. The trajectories of the wheel points motion of the conventional structural design: 1 – cycloid, 2 – elongated cycloid.

The theory of cycloidal curves based on the fundamental laws of motion of a circle without sliding was mathematically justified in the works of E. Toricelli, B. Pascal, R. Descartes, P. Fermat in the 18–19 centuries. Mathematical properties of cycloid in the field of practical and applied mechanics were also found in the works of H. Huygens, I. Newton, G. Leibniz, L. Euler, J. Lagrange [1, 3].

Fig. 2. The trajectory of the point B motion at the flange of the wheel with advanced structural design.

3 Research Results Using this theory, let us determine the sliding distance of the wheel flange along the side edge of the rail top, the value of which largely determines the level of differential kinematic resistance to motion. From Fig. 3, it can be seen that the sliding distance of the flange contact point along the side edge of the rail top corresponds to a part of B1B2B3 perimeter of CB1B2B3 loop of elongated cycloid. The equations of elongated cycloid in a parametric form are written as follows: xB ¼ r
ða  ðr þ DrÞ
sin aÞ; yB ¼ r
ð1  ðr þ DrÞ
cosÞa:

ð1Þ

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The length of the arc of a plane curve in its parametric setting in the general case is calculated by the following formula: Za2 qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi L¼ ½x0 ðaÞ2 þ ½y0 ðaÞ2 da:

ð2Þ

a1

From Fig. 3, it can be seen that the loop perimeter CB1B2B3 of the elongated cycloid is approximated well by an ellipse B1B2B3B4. Part of the perimeter of ellipse B1B2B3 represents sliding distance of point B along the side edge of the rail top, which is interesting to us. It is obvious that length of simiaxis a of ellipse B1B2B3B4 is equal to Dr. To determine the length of the semiaxis b of ellipsis, the design scheme presented in Fig. 4 shall be considered. When the wheel is rolling along the rail at some point in time t, when the wheel turns, point B1 located on the wheel flange reaches the level of the horizontal line PP passing through the point of contact of the wheel with the rail A and contacts with the side edge of the rail top. In this case, in order to point A1 lying on same radius OB1 with point B1 at the rolling surface the wheels also shall contact with the rail at point A2, the wheel should be turned in the direction of its rotation at a certain angle a. This angle will be calculated as follows: a ¼ arccosðr=ðr þ DrÞ:

ð3Þ

Then distance of section A2B, which is equal to length of ellipsis semiaxis b (taking [

into account that jAA2 j ¼ AA1 ), is determined as follows: jA2 B1 j ¼ jAB1 j  jAA2 j ¼ ðr þ DrÞ
sin a  r
a:

ð4Þ

Thus, in the first approach, the sliding distance of the contact point of the flange with the rail along the side edge of its top is half of the perimeter B1B2B3 of ellipsis B1B2B3B4. The parametric equations of the ellipse are written as follows: yðaÞ ¼ b
sin a ; xðaÞ ¼ a
cos a ; 0  a  2p:

ð5Þ

Taking into account (2) and (5), the ratio for determining the length of ellipse arc can be written as follows: Za2 rffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi b L¼a
1  ð Þ2
cos2 a
da: a a1

ð6Þ

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Fig. 3. Loop of elongated cycloid.

Fig. 4. Design diagram.

The integral (6) is an elliptic integral of the second kind and cannot be solved analytically. Therefore, to determine the length of the ellipse perimeter part B1B2B3, we use the well-known approximate formulas for finding the length of the ellipse perimeter LE. The greatest accuracy in the range 0.05 < a/b < 20 according to literary sources is provided by Ramanujan formula [1, 15]: h pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffii LE  p
3
ða þ bÞ  ð3
a þ bÞ
ða þ 3
bÞ :

ð7Þ

So, when the eccentricity of the ellipse of *0.980 (axis ratio of *1/5), inaccuracy of calculation is *0.02%. The inaccuracy is always negative. In our case, the length Lf of sliding distance of B point of flange along the side edge of the rail top along the elementary perimeter of the elongated cycloid loop (arc length B1B2B3) equals LC 

pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffii p h
3
ða þ bÞ  ð3
a þ bÞ
ða þ 3
bÞ : 2

ð8Þ

In general case, the length Lf of sliding distance of B of flange along the side edge of the rail top is less than calculated as per Eq. (8), since depending on the geometry of contact, as well as the degree of wear of wheel flanges and rails, B point of flange contacts with rail not when it reaches the level of PP line, but slightly lower (line P*P*, ref. Fig. 5).

Fig. 5. Contact scheme of wheel and worn rail.

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Thus, the value of length of the wheel flange sliding distance along the side edge of the rail top LГ along the elementary perimeter of the elongated cycloid loop can be expressed in terms of the wheel geometrical parameters taking into account the contact conditions of the wheel flange and the rail: pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi p Lf  K 

ð3
ðDr þ bÞ  ð3
Dr þ bÞ
ðDr þ 3
bÞÞ 2 pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi  p ¼ K

ð3
ðDr þ bÞ  3
ðDr 2 þ b2 Þ þ 10
Dr
bÞ; 2

ð10Þ

where K*is a correction factor depending on contacting, b ¼ ðr þ DrÞ
sinðarccosðr=ðr þ DrÞÞ  r
arccos ðr=ðr þ DrÞÞ:

ð11Þ

In order for flange B point to pass sliding distance Lf along side edge of the rail top, the wheel shall be turned at angle 2a. Then, the total sliding distance along the side edge of the rail top per revolution of the wheel is as follows: LR1 f ¼

2
p p
Lf ¼
Lf : 2
a arccosðr=ðr þ DrÞÞ

ð12Þ

Friction work in the flange contact, which determines the value of the differential component of the kinematic resistance to the wheel motion, is proportional to the flange sliding distance along the side edge of the rail top: Af  F
l
Lf ;

ð13Þ

where l is frictional factor in the flange contact, F is the value of the guiding force in the flange contact. Figure 6 shows an example of graph of dependence of the total friction work value Af in the flange contact per revolution of the wheel on Dr and K* at fixed values F = 50 kN, l = 0.25, r = 0.475 m.

Fig. 6. Dependency graph Af (Dr, K*).

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So, for example, according to the graph, for values Dr = 0.01 m and K* = 0.9, Af is approximately 0.4 kJ. Considering that in one revolution, the wheel travels over distance of about 3 m, the corresponding value of the total fiction work in the flange contact for 1 km of the traveled distance under the considered motion conditions is about 130 kJ. This value may be significantly less for the case of motion of the advanced design wheel due to the above features of its kinematics. The sliding distance in this case will not exceed the value: LR1 ¼ f

2
p  2
K 
p
Dr
Lf  : 2
a arccosðr=ðr þ DrÞÞ

ð14Þ

Thus, the use in the undercarriage of rail vehicles of wheels with an advanced structural design can significantly reduce the sliding distance of wheel flanges along the side edges of rail tops and thereby decrease the differential kinematic resistance to motion and wear of the contacting surfaces of the wheel and the rail. It should be noted that the above calculations are valid for the conditions of wheel motion when the angle of its striking against the rail is zero. At a nonzero angle of striking, the above ratios may be slightly changed and the clarification of their nature requires additional studies.

4 Conclusions Using the theory of cycloidal curves, we obtained an analytical expression for determining the length of the wheel flange slip path along the side face of the rail head, taking into account the conditions of their contact. The magnitude of the work of the friction forces in the flange contact, which determines the magnitude of the differential component of the kinematic resistance to the movement of the wheel, is proportional a langht to the flangt slip path along the side face of the rail head. This makes it possible to carry out a preliminary assessment of the level of the differential component of the kinematic resistance to the movement of rail vehicles. Including for to produce a comparative assessment of the wheels of various design schemes in terms of the level of resistance to their movement. The value of the correction factor K  should be taken depending on the conditions of contact between the wheel and the rail and the degree of their wear. Using the proposed theory, the analysis of rolling characteristics along the rail of wheels of promising constructive design scheme. The results obtained give grounds to assert that the use of such wheels in the undercarriage of rail vehicles may make it possible to reduce the differential kinematic resistance to their movement. This is possible by reducing the slippage of the flanges of the wheels along the side surfaces of the rail heads when using of the wheels perspective constructive scheme.

References 1. Akopian, A.V., Zaslavskii, A.A.: Geometricheskie svoistva krivyh vtorogo poriadka (Geometrical properties of second kind curves). MCNMO, Moscow (2007). 136 p. 2. Astakhov, P.N.: Soprotivlenie dvizheniu zheleznodorozhnogo podvizhnogo sostava (Resistance to motion of railway rolling stock). Transport, Moscow (1966). 178 p.

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3. Berman, G.N.: Cikloida (Cycloid). Nauka, Moscow (1980). 112 p. 4. Bondarenko, L.M., Dovbnia, M.P., Loveikin, V.S.: Deformaciini opory v mashynah (Deformation resistance of machines). Dnipro-VAL, Dnipropetrovsk (2002). 200 p. 5. Vinnik, L.V.: Diss. dokt. tehn. nauk. Problemy mehaniki podvizhnogo sostava s novymi konstrukcijami kolesnyh par (Thesis for a doctor’s degree in Technical Sciences. Problems of rolling stock mechanics with new wheelset designs). MIIT, Moscow, 720 p. 6. Golubenko, A.L.: Sceplenie kolesa s relsom (Wheel-rail adhesion). VUGU, Lugansk (2006). 476 p. 7. Grebeniuk, P.T., Dolganov, A.N., Nekrasov, O.A., Lisicyn, A.L.: Pravila tiagovyh raschetov (Traction calculation requirements). Transport, Moscow (1985). 287 p. 8. Gorbunov, M.I., Fomin, O.V., Kovalenko, V.V., Domin, R.Yu.: Theoretical foundations for conceptually new rolling stock modules, Part 1. Volodymyr Dahl East Ukrainian National University, Sievierodonetsk (2017). 100 p. 9. Mikhailov, E., Semenov, S., Tkachenko, V., Sapronova, S.: Reduction of kinematic resistance to movement of the railway vehicles. In: MATEC Web of Conferences, vol. 235, p. 00033. EDP Sciences (2018). https://doi.org/10.1051/matecconf/201823500033 10. Sapronova, S.Yu., Tkachenko, V.P., Fomin, O.V., Kulbovskii, I.I., Zub, E.P.: Rail Vehicles: The resistance to the motion and the controllability, Monograph. Ukrmetalurginform STA, Dnipro (2017). 160 p. 11. Tkachenko, V., Sapronova, S., Kulbovskii, I., Fomin, O.: Research into resistance to the motion of railroad undercarriages related to directing the wheelsets by a rail track. Eastern Eur. J. Enterpr. Technol. 5/7(89), 65–72 (2017). https://doi.org/10.15587/1729-4061.2017. 109791. Kharkiv, PC «Technology center» 12. Tkachenko, V.P.: Kinematicheskoe soprotivlenie dvizheniu relsovyh ekipazhei (Kinematic resistance to the movement of rail vehicles). VUGU, Lugansk (1996). 200 p. 13. Cygankov, P.Ju.: Dis. kand. tehn. nauk. Sovershenstvovanie konstrukcii telezhek skorostnyh lokomotivov s celiu uluchshenia ih dinamiki (Thesis for a doctor’s degree in Technical Sciences. Improving the design of high-speed locomotives carriages for their dynamics improvement), Moscow (2002). 197 p. 14. Shiler, V.V., Galiev, I.I., Shiler, A.V.: Peculiarities of clutch forming rails and wheel block construction. IOP Conf. Ser. Mater. Sci. Eng. 327(4), 042117 (2018) 15. Hardi, G.: Dvenadcat lekcii o Ramanudzhane (Ramanujan: Twelve Lectures). Publishing House: Institut Computenykh issledovanii, Moscow (2002). 336 p. 16. Lindgreen, E.: Driving resistance from railroad trains. DTU, Copenhagen (2005). 86 p. 17. Lukaszewicz, P.: Energy consumption and running time for trains. Doctoral thesis. KTH, Stockholm (2001), 154 p. 18. Mikhaylov, E., Semenov, S., Panchenko, E.: The possibility of reducing kinematic slip with two-point contacting with rail wheel railway vehicle. Teka. Comm. Mot. Energ. Agric. 13 (3), 139–145 (2013) 19. Rakhmaninov, V.I., Andreyev, A.V.: Practical ways to estimate reduction of resistance to train motion when applying lubricant on lateral sides of rails. In: International Heavy Haul Association STS - Conference Wheel - Rail Interface, vol. 2, pp. 541–543 (1999) 20. Sapronova, S., Tkachenko, V., Fomin, O., Gatchenko, V., Maliuk, S.: Research on the safety factor against derailment of railway vehicles. Eastern Eur. J. Enterp. Technol. 6/7(90), 19–25 (2017). https://doi.org/10.15587/1729-4061.2017.116194. Kharkiv. PC «Technology center»

Ensuring the Cycling Safety by Improving Bicycle Infrastructure Irina Makarova1(&)

, Aleksey Boyko1 , Ksenia Shubenkova1 and Anton Pashkevich2

,

1

Kazan Federal University, Syuyumbike pr-t, 10a, 423822 Naberezhnye Chelny, Russia [email protected], [email protected], [email protected] 2 Tallinn University of Technology, 19086 Tallinn, Estonia [email protected]

Abstract. The paper deals with the relevant problem: ensuring safety and sustainability of urban transport systems. Authors have considered existing positive world wide experience of both infrastructure and managerial solutions. Using the city of Naberezhnye Chelny as an example, a method is proposed for improving the safety of transport systems by improving cycle structures. To reach this, authors have conducted a study of the prospects for the development of bicycle transport in the city by caring out a survey of the population. On the basis of the conducted research, the effectiveness of the proposed solution for the development of bicycle transport was revealed. To implement this solution, the authors of the article have developed DSS for assessing the effectiveness and safety of infrastructure projects. Case study of Naberezhnye Chelny is an example of the implementation and the possibility of using the proposed DSS; however, this intelligent system is universal and can be applied to any city. Keywords: Bicycle infrastructure


Transports safety
Last mile problem

1 Introduction The twenty-first century is called the century of urbanization, because there is an increase in the proportion of urban population in the world. Cities sometimes develop into urban agglomerations, absorbing suburbs and forming zones of continuous development, functionally closely connected with the core of the city. Such accretion is stimulated by the development of transport, the growing “reachability” of any point of agglomeration – daily work trips, called “pendulum migrations”, cultural and domestic communications, industrial relations of enterprises of the city and their branches, etc. developed countries. At the same time, if earlier the concentration of industry gave an additional effect (“agglomeration effect”) due to the wide possibilities of combination and cooperation, the use of superconcentration, then later negative moments came to the fore: traffic collapse of cities, water supply difficulties, environmental problems. In this regard, the industry is forced to “leave” from large cities, its place is taken by other functions: science and research and development, financial and management firms, etc. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 386–396, 2020. https://doi.org/10.1007/978-3-030-38666-5_41

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The main transport problem of cities is that cars take up too much space: in terms of one person, cars take up 20 times more space than a tram and 90 times more than a subway. They need space for movement and space for parking. According to the Canadian urbanist Brendt Toderian [1], the world will be saved not by electric cars, but by the correct transport policy, giving priority to pedestrians, public transport and cyclists. Pedestrian infrastructure, public transport and bicycles can save not only urban space, but also money, and also help reduce harmful emissions into the atmosphere and help create healthy and cost-effective cities. However, it is necessary to remember the problems that need to be solved when planning the transport strategies of cities. First of all, these are safety concerns for the road users. Thus, the WHO global report on the state of road safety in 2018 indicates that about 1.35 million people die each year as a result of road accidents [2]. Another 20 to 50 million people get non-lethal injuries, many of them getting disabilities as a result of injuries. Traffic accidents are currently the leading cause of death for people aged 5–29. Cyclists as unprotected road users are one of the most vulnerable groups of road users and roads should be designed with regard of their safety. Any changes in the transport infrastructure require a feasibility study. In addition, since such changes affect the safety of the transport system, it is necessary to take into account the risks and consequences that may result from changes in traffic patterns. For these purposes, a flexible and efficient tool is needed to make (well-founded) decisions. Such a tool can be a decision support system (DSS), where simulation models are its intelligent heart.

2 State of the Problem: Improving the Safety and Sustainability of Urban Transport Systems 2.1

Prospects for the Development of Cycling in Europe

Sustainable development of transport should be an integral part in the design of cities and suburbs in accordance with the principles of planning for their reasonable growth. Urban development in accordance with these principles helps to reduce the dependence on personal vehicles and provides support for the preferential use of public and nonmotorized transport systems for daily trips and short-distance trips. An example of such an approach is set forth in document [3], which identifies three main priorities: (1) the creation of streets and street networks that encourage walking, cycling and the use of public transport; (2) the development of public transport as the most efficient way to travel over distances that are too long for walking or cycling; (3) city planning suitable for walking, cycling and using public transport, which stimulates the construction of new homes and the creation of new jobs in new areas of activity. Progress towards more sustainable modes of transport has a positive impact, subject to the regulation of road safety implications. These effects include increasing physical activity levels, reducing emissions and noise levels, reducing traffic jams and creating cities that are comfortable for life. In addition, measures to promote safe public transport and non-motorized vehicles are consonant with global efforts to combat obesity and reduce the burden of non-communicable diseases (such as heart disease

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and diabetes) [4]. Cycling is an effective way to use expensive and scarce space in urban areas and is healthy, clean and cheap. It has a huge potential when almost half of all urban road trips are less than five kilometers. At the informal meeting of EU transport ministers in October 2015 in Luxembourg, the Declaration on cycling was adopted as a climate-friendly mode of transport [5]. Ministers called on the Commission, member states and local and regional authorities to consider a number of measures in this direction. The Commission is working on the further integration of bicycle traffic into the multimodal transport policy, namely: • strengthening the cycling aspects of ongoing initiatives such as the CIVITAS and the European Mobility Week; • increasing attention to improving road safety due to cycling; • interaction with relevant intergovernmental organizations and interested parties through a contact representative on cycling issues; • strengthening transport statistics related to cycling. Strategic planning includes the development of methods for ensuring sustainability on the basis of finding a balance between transport demand and supply, as well as using the most efficient and safe modes of transport. The purpose of managing non-motorized transport is embedding the infrastructure of this type of transport into the overall system of the city’s street network. This will increase its attractiveness for different categories of the population, on the one hand, and ensuring the personal safety of nonmotorized road users, on the other. 2.2

Infrastructure Solutions to Improve Safety

Today there is a misconception “More roads – less congestion!”. However, experience shows that new roads do not reduce traffic loads. The more comfortable to drive in any region, the more people buy cars, which again causes congestion. Reducing the number of conflict points where pedestrian flows, motorized and non-motorized vehicles intersect is the most effective way to improve the safety of the transport system. In the absence of clear rules and appropriate infrastructure, the interaction of traffic participants moving at different speeds is unsafe. Thus, a cyclist is endangered while moving in a traffic flow, but when he is cycling on the sidewalk, pedestrians may suffer. The pace of development of the bicycle infrastructure and its effectiveness depends, first of all, on the size and breadth of the city. Thus, in small compact cities, bicycle transport can develop as an independent mode of transport, with the bicycle infrastructure becoming part of the road network. In large cities with heavy traffic, bicycle transport, as a rule, complements the public transport system, being essentially individual transport, with the help of which they get to the desired point. This is the problem of the first and last mile. The active development of the cycling movement stimulates the development and implementation of bicycle infrastructure projects by municipalities and initiative groups, which will improve the safety of cyclists and the quality of their interaction with other road users. One of the first original transport infrastructure projects for London was the SkyCycle project to create new safe bicycle routes located high above the existing railway tracks. Routes would have a width of up to 15 m (49 ft), 200 points of entry and exit throughout the city. Project developers

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have calculated that the bike lanes accommodate 400,000 riders at peak hours and save 30 min compared to the current trip time [6]. Dominican designer Richard Moreta Castillo has offered a 10 km bike path called Bicimetro Eco Bahn, which consists of two tubes of glass and steel, held by a series of futuristic props. Tunnels protect cyclists from road hazards such as potholes, car doors and vehicles. They are crowned with energy-generating wind turbines and photovoltaic panels [7]. Similar solutions have been proposed for Moscow and Kazan [8, 9]. For Russia, the topic is relevant not only because of the need to divide the space, but also to protect cyclists in difficult weather conditions. Notable examples of the safety of cyclists are the Cykelslangen cycle bridge in Copenhagen, which connects two areas [10] and the cycle bridge Jan Waaijer in the Netherlands [11]. The integration of bicycle transport with public transport does not apply to all types of urbanized areas, since each type has a different focus on the use of bicycle transport. A qualitative assessment of the integration of bicycle transport into the city’s transport network is given in the book by Walker [12]. First of all, he sees the urgent need to use a bicycle as an alternative form of transport in those areas of the city where the use of public transport is not possible. Wang [13] conducts research in the study of providing the possibility of overcoming the last mile through the joint operation of the public transport system and bicycle transport. He focuses on the use of bicycle rentals at railway stations and ATK with integrated integration with route building systems to ensure constant access to bicycles at the time of the request by users. The strategic plan of RTA [14] describes the ways to solve the last mile using various ways to overcome the site: on foot, by bicycle, as well as Car and Ride sharing. Olivia Greenway [15] regards bicycles and electric two-wheeled vehicles as a last-mile solution. She believes that you should not focus only on the use of a classic bike. It is also necessary to focus on electric bicycles, hoverboards, electric scooters and monowheels. Such an approach to solving the problem will increase the sustainability of the transport network. The presented problems should be solved directly by carriers together with the city administration, since the popularization of bicycle transport, as a means of transportation in areas of the city with low profitability of public transport, will reduce the costs for carriers. 2.3

Management in Bike-Sharing Systems

In large cities and metropolitan areas, a bicycle is used as part of multimodal transportation as one of the ways to overcome part of the route in integration with public transport. This type of use of public transport is actively developing in Germany and involves short-term bicycle rental. The cost of 1 km of travel by car on average costs the owner five rubles [16], while the cost of 1 km of bicycle rental or bicycle sharing costs 1.25 rubles. The Moovel mobility system integrates bicycles into the city’s transport network and allows booking and paying for rent [17]. The authors of the article [18] as a result of a survey of 557 respondents identified important aspects to build the correct transport network, one of the most important aspects of which is the location of the bicycle sharing sites. They point out that in the city of Taipei in Taiwan, the train stations and bus stops use the Public Bike System, a network of bicycle transfer points. The author of the article [19], points out the need not only to develop bike-sharing systems, but also to constantly support the popularity of this type of

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transport. He proposes to integrate bike-sharing systems with route building systems, which, in his opinion, will allow to solve the problems of the last mile in Beijing in a comprehensive way. The authors of the article [20] based on a detailed analysis of the GPS data for the bike sharing system and the bicycle mobility model created a demand model. Depending on various factors, such as seasons, weather conditions, time of day and holidays/weekends, the system allows you to predict the upcoming demand at a certain time and place. In connection with the growing interest in sharing bicycles systems in Poland, the authors of the article [21] focused on analyzing the safety aspects of their use. The paper presents the factors that influence the road safety of bicycle sharing users.

3 Results and Discussion 3.1

Exploring the Russian Experience of Creating a Bicycle Infrastructure

The characteristics of an urbanized area, as well as its planning decision, affect the needs of the population in organizing mobility, and, consequently, the parameters of the bicycle infrastructure. Russia currently pays attention to the development of cycling movement. Infrastructure changes depend both on the characteristics of the city and on the goals of cycling. Thus, in [22], measures to improve the safety of the city’s transport system through cycling are analyzed. The author compares the positive changes in different cities of characteristics: Moscow, Kazan and Kaliningrad (see Table 1). Table 1. Possible positive changes after the implementation of architectural planning solutions. Decreasing parameter Travel time saved by cyclists, million h/year Decrease of population morbidity and mortality, people Percentage of safe bike networks, %

Moscow 77.76 … 86.4 102 … 1100

Kazan 9.6 55

Kaliningrad 2.7 17

n/a

98

94.6

If the cities discussed above, due to their size and planning decisions, use bicycle transport, integrating it into the city’s transport system as an addition to public transport, the city of Almetyevsk is a vivid example of cycling as an alternative to road transport. This is a single-industry town with a population of 150 thousand, where almost every family is associated with oil production. The city authorities decided not to wait for traffic jams and not to take another’s path of error with the expansion of streets and the construction of parking lots on the site of the squares. Instead, they decided to motivate residents to use a compact bicycle as a transport today. For this, a team of professionals from Copenhagen was hired with Michael Colville, who prepared

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a project for bicycle paths throughout the city [23]. The purpose of the mayor of the city was the beginning of the large-scale construction of regular cycle paths 200 km long, isolated not only from automobile roads, but also from pedestrian paths. In addition, the development of accompanying bicycle infrastructure objects as in Copenhagen (the city - center of cycling in the world) is envisaged [24]. 3.2

Analysis of the City in Terms of Transport Needs

The size of the city is estimated by the absolute and relative size of the developed area. The absolute value of Sdev is usually determined in square kilometers by applying to the city plan a tour, within all places of work, residence, recreation, treatment and satisfaction of cultural, social, business and other needs of the population are located. The relative value of the urbanized area S is based on one resident of the city according to the formula, where N is the population size: S¼

106
Sdev : N

ð1Þ

To assess the density of the developed territory, the coefficient of the developed territory ao is used: ao ¼

Ao ; Ds

ð2Þ

where Ao is the air remoteness of the developed territory from the main transport hub: P Ao ¼

Siði þ 1Þ ðLi þ Li þ 1 Þ ; 2
Sdev

ð3Þ

where Si ; Si þ 1 is the area of the annular zone between two adjacent circles within the developed territory; Li ; Li þ 1 – the radii of adjacent circles; Ds is the air remoteness of the territory of the same square (having the circle shape) from the center of the circle: Ds ¼

3.3

pffiffiffiffiffiffiffiffi 2
R ¼ 0:377 Sdev : 3

ð4Þ

Case Study of Naberezhnye Chelny: Identifying Potential Cyclists

The transport planning framework of Naberezhnye Chelny city is made up of longitudinal roads connecting residential areas of city, which gives grounds to assign the planning scheme of its street-road network to a rectangular one. The main “diameter” of the city is the longitudinal line, which includes M. Jalil Ave., Naberezhnochelninsky Ave., and Mira Ave. The population of the city is 532,472 people, and the area is 161 km2. By the above method, the density of the developed territory was determined. To do this, the circles after 1 km with a center in the main city transport hub was marked on

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city’s plan. After that the square of each circle zone within the development territory was calculated: A0 = 5.974, Ds = 5.95, a0 = 1.004 (Fig. 1A). The a0 coefficient value means that the developed territory of the city is very compact. For such cities, an effective solution would be to use a bicycle as a way to solve the last mile problem. Since a significant part of travel during peak hours is labor correspondence, the separation of industrial and residential areas in the city creates problems at the intersections of longitudinal and transverse highways. This is due to the fact that there was a network of factory routes for the delivery of workers to industrial zones, the disappearance of which forced workers to transfer to individual transport, since the route network of urban public transport did not undergo significant changes.

Fig. 1. (A) Developed territory of Naberezhnye Chelny; (B) The results of the survey.

In order to identify the prospects for the development of bicycle transport in Naberezhnye Chelny, a survey of the preferences of the population was conducted. 953 respondents representing various target groups took part in the current survey, the results of which (Fig. 1B, C) show that it is possible to increase the number of people choosing a bicycle as a mean of transportation by integrating the infrastructure of this type of transport into a common road network of the city. The respondents noted that there are not enough such infrastructure facilities in the city as: bicycle lanes, safe crossings at the intersection with roads, zones of rest and repairs (self-service station), secured covered parking, rental locations at affordable prices. To study the prospects of this direction, we carried out an ante-ticket among students of the branch of Kazan Federal University and among the young employees of PC KAMAZ. The environment for the implementation of the questionnaire was chosen by the online service “Google Documents”, which has simple tools for creating a questionnaire with well-formed logic and allows you to get a structured result not only in the form of text answers, but also in the form of graphs. 186 students and 102 employees of PC KAMAZ took part in the survey (Fig. 2).

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Fig. 2. The results of a survey of KAMAZ employees.

A survey conducted among students showed that there are not enough equipped parking lots for a bicycle, which makes it difficult to use it. The development of the bicycle infrastructure would expand the number of potential users of bicycle transport, especially through the development of a bicycle-sharing system at public transport stops and bicycle rentals for long-term bicycle rental. The results were analyzed and recorded in a form suitable for further inclusion in the database to select the best option in terms of safety and cost of building additional bicycle and pedestrian infrastructure facilities. 3.4

Development of DSS for Assessing the Effectiveness and Safety of Infrastructure Projects

The development of cycling in cities will lead to an increase in the number of cyclists and the size of their transport work. Therefore, safety requirements for bicycle paths will constantly increase. In this regard, it is important, based on interdisciplinary research, to establish and evaluate the values of safety indicators at different stages of automobile, cycling, and pedestrian traffic from beginning to end the route, i.e. when potentially there is a risk of accidents. The authors of the article [25] believe that the safety of cycling in an urbanized area can be assessed by the magnitude of the hazard level r, which reflects the likelihood of accidents involving cycling. When r = 1, an accident is unavoidable; if r = 0, the probability of an accident is zero. The degree of danger is affected by: the presence of intersections, the frequency and speed of movement of vehicles, the type of bike lane, as well as its width. The safety level of cyclists depends on a variety of statistical and dynamic factors. At the first stage, factors that determine the category of the route by complexity for pedestrians and cyclists were identified. The multi-criteria route safety assessment algorithm was presented in our previous papers [26, 27]. Since the significance of a factor for different categories of road users is determined by their characteristics, to determine the weight of factors, categories of pedestrians and cyclists were identified by age and health status [28]. The route can be estimated using a complex indicator, which is calculated using the weighted average formula: Pn i¼1 Ki
ai K¼ P ! min; n i¼1 ai

ð5Þ

where Ki is the value of the i-th parameter; ai is the weight of the indicator. In order to summarize dissimilar indices in the formula their reduced values are calculated.

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Since a significant part of moving around the city is made up of combined routes, the transfers number on the route should be estimated, because it is the interchange points safety on such routes that can be decisive. We propose to predict the effectiveness of projects, choosing from several options that which will initially be most appropriate in each case considered. For these purposes, it is proposed to develop a decision support system, the intellectual core of which will be simulation models. A conceptual model of a decision support system consists of (Fig. 3A): (1) a module for collecting, storing and administering data on the quantitative and qualitative properties of bicycle infrastructure objects, parameters of the transport system, as well as monitoring data on the parameters of cycling and pedestrian flows; (2) module for analysis of statistical and dynamic data; (3) a module for decision making with the purpose of analyzing and evaluating data and the subsequent development of recommendations (calculation of the track width based on passenger traffic and throughput of the existing bicycle infrastructure; justification of the need for other infrastructure facilities); (4) module for development of simulation models before/after changes in accordance with the received recommendations); (5) module (Fig. 3B) for choosing the optimal route that will help to assess the safety of both existing and projected infrastructures.

Fig. 3. (A) Conceptual diagram of the DSS; (B) View of the developed module.

4 Conclusion Since any infrastructural changes require a lot of resources, all decisions should be based on scientific researches and supported by computer simulations. For this purpose, firstly, we have conducted the surveys among those groups of population in the city under study, which can be interested in the use of bicycles for solving the Last Mile Problem. Results of the survey showed that 19% of all respondents are ready to use the bicycle on the daily basis if there are safe bicycle lanes and 10% – if the bicycle is

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integrated into the public transport system. This led us to conclusion that our idea of the DSS, which will help to plan bicycle infrastructure facilities, is relevant. At the current stage, we have created the concept of the DSS and have developed one of the planned modules: module for choosing the optimal route taking into account safety issues. The next step is to use cyclists and pedestrian counters to ensure dynamic data collection for the information system. Similar systems are actively used not only in capitals, but also in other cities, for example, in Kazan and Almetyevsk (Russia).

References 1. Transportation + mobility, Toderian Urban Works. http://www.toderianurbanworks.com/ portfolio/transportation-mobility/. Accessed 17 Jan 2019 2. Global status report on road safety 2018. https://www.who.int/violence_injury_prevention/ road_safety_status/2018/en/. Accessed 15 Jan 2019 3. Mayor’s Transport Strategy. https://www.london.gov.uk/sites/default/files/mayors-transportstrategy-2018.pdf. Accessed 25 Dec 2018 4. Sustainable Urban Transportation, Creating green liveable cities. https://stateofgreen.com/en/ uploads/2016/06/Sustainable-Urban-Transportation.pdf?time=1538088932. Accessed 07 Jan 2019 5. Informal meeting of Ministers for Transport (2015). http://www.eu2015lu.eu/en/agenda/ 2015/10/07-info-transports/index.html. Accessed 07 Jan 2019 6. SkyCycle, Foster + Partners. https://www.fosterandpartners.com/projects/skycycle/. Accessed 07 Jan 2019 7. Bicimetro Eco Bahn: Elevated Bike Tunnels Let Cyclists Soar Above Congested City Traffic, Inhabitat. https://inhabitat.com/bicimetro-eco-bahn-lets-cyclists-soar-abovecongested-city-traffic/. Accessed 16 Jan 2019 8. An alternative to bicycle paths was proposed by Kazan architects: cycle-politics, Inkazan.ru. http://inkazan.ru/2014/01/21/alternativu-velodorozhkam-predlozhili-kazanskie-arhitektoryivelopoliten/. Accessed 14 Jan 2019 9. Bicycle roads, Varlamov. http://varlamov.ru/979334.html. Accessed 15 Jan 2019 10. Cycle bridges of the world, Part I, Cykelslangen (Copenhagen). http://veloman.uz/blog/ velotourism-cycling/66485/. Accessed 10 Jan 2019 11. Cycle bridges of the world, Part II, Jan Waaijer (Netherlands). http://veloman.uz/blog/ velotourism-cycling/66485/. Accessed 09 Jan 2019 12. Walker, J.: Human Transit: How Clearer Thinking About Public Transit Can Enrich Our Communities and Our Lives. Island Press, Washington, D.C. (2012). 244 p 13. Wang, H., Odoni, A.: Approximating the Performance of a “Last Mile” Transportation System, http://dx.doi.org/10.1287/trsc.2014.0553. Accessed 25 Feb 2018 14. Transit Strategies, First and last mile connections. http://nmotion.info/wp-content/uploads/ 2015/09/nMotion-First-Mile-Last-Mile-150920_FINAL.pdf 15. Greenway, O.: Fixing the first and last mile problem. https://www.inmotionventures.com/ fixing-the-first-and-last-mile-problem/. Accessed 02 Mar 2018 16. 15 Most profitable cars, sravni.ru. https://www.sravni.ru/text/2015/9/9/15-samykhvygodnykh-avtomobilej-v-segmente-do-15-mln-rub/. Accessed 20 May 2018 17. An urban mobility company, making cities smarter, Moovel. https://www.moovel-group. com/en. Accessed 20 May 2018 18. Pai, J.T., Pai, S.: User behaviour analysis of the public bike system in Taipei. Int. Rev. Spat. Plann. Sustain. Dev. 2, 39–52 (2015)

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19. Zhili, L., Ji, X., Cheng, W.: Solving the Last Mile Problem: Ensure the Success of Public Bicycle System in Beijing. https://www.sciencedirect.com/science/article/pii/ S1877042812009603. Accessed 27 Feb 2018 20. Reiss, S., Bogenberger, K.: A relocation strategy for Munich’s bike sharing system: combining an operator-based and a user-based scheme. Transp. Res. Proc. 22, 105–114 (2017) 21. Turoń, K., Sierpiński, G.: Bike-sharing as a possibility to support Vision Zero. In: MATEC Web of Conferences, vol. 231, p. 03005 (2018) 22. Trofimenko, Y., Shashina, E.: Methodology and results of assessing safety of bicycle infrastructure in Russian cities. In: SPbOTSIC 2016, pp. 653–658 (2017) 23. Almetyevsk: 50 km of bike paths built, letsbikeit.ru. https://letsbikeit.ru/2016/10/ almetyevsk/. Accessed 17 Jan 2019 24. Plepys, A., Heiskanen, E., Mont, O.: European policy approaches to promote servicizing. J. Clean. Prod. 97, 117–213 (2015) 25. Trofimenko, Y., Shashina, E.: Methodology and results of assessing safety of bicycle infrastructure in Russian cities. Transp. Res. Procedia 20, 653–658 (2017) 26. Makarova, I., et al.: The system of the school routes’ development and their safety assessment. In: Lecture Notes in Networks and Systems, vol. 36, pp. 65–74 (2018) 27. Shubenkova, K., Boyko, A., Buyvol, P.: The technique of choosing a safe route as an element of smart mobility. Transp. Res. Procedia 36, 718–724 (2018) 28. Makarova, I., Pashkevich, A., Shubenkova, K.: Safe routes as one of the ways to reduce the number of road accidents victims. In: Lecture Notes in Networks and Systems, vol. 21, pp. 73–84

Climatic Chamber Testing of Innovative Brake System for Rolling Stock Tasko Smileski(&) and Gligorche Vrtanoski Faculty of Mechanical Engineering Skopje, Ss. Cyril and Methodius University in Skopje, Skopje, Republic of Macedonia [email protected], [email protected]

Abstract. In this paper is shown climatic chamber testing of an innovative brake system for rolling stock. Brake systems have the essential function of decelerating and stopping of rolling stock. As railway operators focus on the need for greater improvements in efficiency and safety, there is still a significant need for advancements in the brake systems. Since the brake systems are a subject of large static and dynamic loads in external conditions, lot of tests need to be performed to validate the function. In this paper will be shown one of the most important testing of the brake systems - climatic chamber testing. Keywords: Railway


Climatic chamber
Brake system

1 Introduction Rail transport provides a very important role in society, not only to allow large number of people to get to work every day, but also for transport of goods. The development of rail transport in recent decades is aimed at increasing the speed and loading performance of the railway vehicles. This directly affects the development of the brake technology [5]. The brake system has an essential function in reducing the speed and braking of the rolling stock for minimum possible time [3]. In terms of safety, it is more important that the railway vehicle is able to stop, than to move. The brake system function is to ensure a safe deceleration and stopping of the railway vehicle when necessary. This shows that the brake system plays a vital role in the safety of railway vehicles. Bearing in mind the importance of braking equipment in railway vehicles, all railways pay special attention on the development and maintenance of brake systems. As railway operators focus on the need for greater improvements in efficiency and safety, there is still a significant need for advancements in the brake systems [2]. Several types of brake systems are used in the railways. Most commonly used compressed air brake systems, called pneumatic brake systems [1]. Tread brake systems are classic type of mechanical systems that are most commonly used in freight rolling stock [7]. Climatic chamber testing is one of the most important testing that is necessary to be done on brake systems according to the standard UIC 541-01 [9]. It is very important that the brake systems will work properly under different weather conditions. One example of testing in harsh weather conditions is done by the researchers Olofsson, © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 397–406, 2020. https://doi.org/10.1007/978-3-030-38666-5_42

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Sundh, Bik and Nilsson [10] who analyzed the impact of snow on the performance of the braking systems in railroad vehicles. The obtained results from the climatic chamber test of the innovative brake system IBB 10 will indicate whether the brake system meets the UIC standard criteria.

2 Model of Innovative Brake System As railway operators focus on the need for greater improvements in efficiency and safety, there is a significant need for improvements of the brake systems [6]. Advanced brake systems lead to many benefits like improvements in the load capacity, increasing the safety and optimized life cycle costs. The proposed model of the innovative brake system IBB 10 is intended for use in freight wagons and has the lowest weight on the market. It consists of a brake cylinder which through a system of levers and slack adjusters, transfers the force on the brake shoe holders and onto the brake shoes that come in frictional contact with the wheels of the wagon. The brake force is achieved through the brake cylinder and multiplied by the levers. Two slack adjusters serve to compensate the wear of the brake shoes and wheels. This brake system design allows easy assembly and disassembly on each subassembly separately, which is a great advantage in maintenance and repair of the system. The innovative IBB 10 brake system can be fitted between the wheels of a bogie type Y25 or similar and it fits the standard built-in measures as the conventional brake system. The function of the innovative brake system is to provide approximately equal brake force on all four wheels at the same time. The design consists of a brake cylinder with (or without) a hand brake and two slack adjusters for automatical adjustment of the gap between the wheels and brake shoes. In Fig. 1 is shown the innovative system IBB 10 without hand brake. This model of the innovative IBB 10 system is the base for all other variants.

Fig. 1. Model of innovative brake system IBB 10 without hand brake [6].

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The service brake force is calculated according to the following Eq. (1): F ¼ ðp
S
10  FB Þ
i
g  FS ðN Þ;

ð1Þ

where p – brake cylinder pressure (bar); S – effective piston area (cm2); FB – return spring force (N); i – lever ratio; g – efficiency; FS – slack adjuster counterforce (N). From all the listed factors that influence the service brake force, only the brake cylinder pressure is a variable, while all other factors are constant. Taking in account the fact that for different types of freight wagons a different brake force is needed, and the pressure p is defined according to the UIC standard, from design point of view the ratio of the levers i can be changed. The innovative brake system IBB 10 is installed on one bogie, and since one freight wagon usually has two bogies, in most cases, two IBB 10 systems will be installed per wagon as a set. Because each freight wagon should have parking option when is removed from the train composition (or because some other reasons), at least one IBB 10 unit must have a parking hand brake. In Fig. 2 is shown a variant of the innovative brake system IBB 10 with a platform hand brake. This brake system with platform hand brake has the same function as IBB 10 without hand brake, but with added function of the hand application of a parking brake. The application of the platform hand brake is done from the platform of the wagon.

Fig. 2. Model of innovative brake system IBB 10 with platform hand brake [6].

The activation of the platform hand brake should be performed from the platform of the freight wagon by turning the hand wheel through a box with conical gears and a telescope cardan shaft which is connected to the spindle of the platform hand brake mechanism. In Fig. 3 is shown a model of Y25 bogie with installed brake system IBB 10 with platform hand brake and connecting components for activation with segment of the wagon platform.

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Fig. 3. Model of Y25 bogie with installed brake system IBB 10 with platform hand brake and connection components for activation with segment of the wagon platform.

By turning the hand wheel, the torque is transmitted through the gears and the cardan shaft to the spindle of the platform hand brake mechanism activates (extends) the brake cylinder. This mechanism is connected to the piston rod and during service brake it moves together with the piston rod. The connection of the hand brake to the platform is necessary to be performed with a telescope cardan shaft in order not to decrease the degrees of freedom of the brake system during braking and releasing.

3 Climatic Chamber Testing In the process of verification and validation of a new product, several types of testing should be included, depending on the need and definitions in the standards. One of these tests is the climatic chamber testing. Figure 4 shows a block diagram of the testing of the innovative braking system IBB 10 in a climatic chamber. As can be noted, some of the components which are needed to perform the test are located outside the climatic chamber, while certain components are located inside the climatic chamber. In the climatic chamber it is necessary to be located the innovative IBB 10 brake, 100 L reservoir R1, pressure sensor TP1, force sensors and water hose. Readable data is the pressure in the brake cylinder and the brake forces at 4 measuring points which are shown on the brake force reader. The pressure sensor and the brake force sensor are connected to a computer so that the brake force can be measured depending on the pressure in the brake cylinder. The computer and the brake force reader need to be connected to a power supply.

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Fig. 4. Block diagram of IBB 10 climatic chamber testing [8].

The way in which the brake cylinder pressure is applied is through compressed air supply from 8 to 10 bar, which is connected to the reservoir R1. This reservoir allows compressed air to be applied to the brake cylinder at almost the same temperature as in the climatic chamber. To regulate the pressure in the brake cylinder, pressure regulator VLV1 is used. Through the cock C1 can be regulated the air flow to the brake cylinder. The cock is used for testing the air tightness of the brake cylinder. To be able to perform an ice test, around the innovative brake system IBB 10 is installed hose with water. This test is performed by spraying water on the IBB 10 unit which is done by activating cock C3. In order to prevent the water in the hose to freeze and also the jet of water to be stronger, the compressed air supply is used which through the cock C2 and the non-return valve NRV is mixed with the water. Figure 5 shows a photograph of the IBB 10 brake system with platform hand brake installed on the test bench and placed in a climatic chamber. Large number of the elements listed in the block diagram, such as the reservoir, pressure sensor, water hose and others, can be seen in the photograph. The circular openings in the climatic chamber serve to connect the measuring devices with cables, to implement the air connection and the supply of water with hose. Due to the large mass of the test bench, together with the installed brake system, it is placed on wooden pallets in order not to damage the base of the climatic chamber.

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Fig. 5. Photograph of IBB 10 with platform hand brake on test bench in climatic chamber [4].

Brake force hysteresis testing is one of the basic tests that need to be done on brake systems. The method of this testing is defined in the standard UIC 541-01. As specified in this standard, it is necessary first to test at a temperature of +20 °C. Figure 6 shows brake force hysteresis diagram of the brake system IBB 10 with platform hand brake at temperature of +20 °C. In this case, the measured forces are F1, F2, F3 and F4. When all prescribed tests at a temperature of +20 °C are completed, the next temperature at which the brake system IBB 10 is subjected is −40 °C.

Fig. 6. Brake force hysteresis of IBB 10 with platform hand brake at temperature of +20 °C [4].

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Figure 7 shows photographs of testing IBB 10 brake system with platform hand brake at temperature of −40 °C.

Fig. 7. Photographs of testing IBB 10 with platform hand brake at temperature of −40 °C [4].

Figure 8 shows brake force hysteresis diagram of IBB 10 with platform hand brake at temperature of −40 °C.

Fig. 8. Brake force hysteresis of IBB 10 with platform hand brake at temperature of −40 °C [4].

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Figure 9 shows photographs of the ice test on the IBB 10 brake system with applied platform hand brake. This test is performed in order to simulate a situation when the brake system with applied platform hand brake is frozen.

Fig. 9. Photographs of ice test on IBB 10 with applied platform hand brake [4].

Figure 10 shows a diagram of temperature change in the climatic chamber from room temperature up to +70 °C. As can be noticed, the temperature increase of around 45 °C occurs in approximately 2 h and the stabilisation phase is larger than 9 h.

Fig. 10. Diagram of temperature change in the climatic chamber from room temperature up to +70 °C [4].

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Figure 11 shows brake force hysteresis diagram of IBB 10 with platform hand brake at temperature of +70 °C.

Fig. 11. Brake force hysteresis of IBB 10 with platform hand brake at temperature of +70 °C [4].

4 Conclusion This paper shows one part of the development of an innovative brake system for rolling stock. Considering that the brake systems are of great importance for the safety of rail traffic and are exposed to large static and dynamic loads under external conditions, the development of a such system is a long and complex process. In the process of developing a brake system, the most important asset is to use the most advanced software, methods and techniques. Climate chamber testing is one of the most important testing of the brake system because it shows the behaviour of the brake system in different temperatures prescribed by the UIC standard. The minimum temperature is −40 °C, while the max. temperature is +70 °C. The results of all tests are positive, which means that the innovative braking system IBB 10 has successfully completed the climatic chamber testing and that the brake system satisfies the UIC standard criteria and meets the requirements of the customers. By successfully passing the climatic chamber test, there is a significant increase of chances that the innovative brake system will successfully pass the field test and will be launched onto the market.

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References 1. Chary, R., Khan, E.: Design and analysis of train brake system. Int. J. Adv. Res. Innov. 7(3) (2014) 2. Wynd, D., Connelly, M.: Advanced bogie brakes. In: Proceedings, Conference on Railway Engineering, Wellington (2010) 3. Sharma, R.C., Dhingra, M., Pathak, R.K.: Braking systems in railway vehicles. Int. J. Eng. Res. Technol. 4(01), 206–211 (2015) 4. Smileski, T.: Development and optimization of innovative product for rolling stock. Master thesis, Faculty of Mechanical Engineering Skopje, University “Ss. Cyril and Methodius” (2018). (in Macedonian language) 5. Smileski, S., Smileski, T.: Integrated bogie brake and slack adjuster for the use with said integrated bogie brake, Patent WO 2013098350 A2 (2011) 6. Smileski, T., Rakipovski, R., Mičić, M.: Comparison of classical brake for freight wagons with new integrated bogie brake IBB 10 for freight wagons. In: RAILKON 2016, Niš (2016) 7. Teimourimanesh, S., Vernersson, T., Lunden, R.: Modeling of temperatures during railway tread braking: influence of contact conditions and rail cooling effect. Proc. Inst. Mech. Eng. Part F J. Rail Rapid Transit 228(1), 93–109 (2012) 8. Denti, M., Brambatti, A., Poli, C.: Integrated bogie brake type IBB 10 with platform hand brake - Functional Tests in climatic chamber. Test report, PoliSrl - Technical Department, Camisano (2015) 9. UIC 541-01: Brakes - Brake cylinders/units for air brakes - General conditions for certification and use (2017) 10. Olofsson, U., Sundh, J., Bik, U., Nilsson, R.: The influence of snow on the tread braking performance of a train: a pin-on-disc simulation performed in a climatic chamber. Proc. Inst. Mech. Eng. Part F J. Rail Rapid Transit 230(6), 1521–1530 (2015)

Adapting a One-Dimensional Mathematical Model to the Dual Fuel Engine In-Cylinder Processes Modelling Sergėjus Lebedevas(&), Vygintas Daukšys, and Linas Jonika Klaipeda University, Bijūnų str. 17, 91225 Klaipėda, Lithuania [email protected] Abstract. The article presents results from numerical studies evaluating onedimensional mathematical model (MM) with single-phase I.I. Vibe combustion law for dual fuel (DF): diesel (D) and natural gas (NG) engine energy experiment. Adequacy criteria were established for high speed 4ČN79,5/95,5 engine with conventional fuel system, engine was tested on D100 and D20/NG80 fuel, in high (HLM), medium (MLM) and low (LLM) engine load modes, changing diesel injection angle (DIT) from −1 to −13° CA BTDC range for each load. The simulation of single-phase I.I. Vibe’s law of combustion is characterized by limited application possibilities. The rationality of single-phase model use was determined only in HLM engine mode (with error 7%). In the MLM and LLM regimes, the mismatch between real bi-phasic combustion with highly dispersed natural gas NG diffuse during second phase modelling error is 50%. Keywords: Mathematical model Combustion law


Duel-fuel engine
Energy indicators


1 Introduction Use of natural gas NG to replace fossil fuels of petroleum origin in diesel engines (DE) is one of the most promising directions for strategic development in the reduction of harmful emissions and greenhouse gas emissions in transport [1–3]. In parallel with the extensive experimental research, much attention is paid to the development of mathematical modelling technologies. Multi-dimensional mathematical models are preferred among numerical models. Multi-dimensional mathematical models (MM) are implemented in different software packages, effective in solving the incompressible moment (Navier-Stokes), energy (Furje-Kirghof), conservation of mass equations: FIRE (AVL, Austria), KIVA (Laboratory of Energy Research, USA) and VECTIS (Ricardo, England) [4–9]. Along with the use of modern multi-dimensional MM in internal combustion engine (ICE) practice, including engines which are retrofitted for dual fuel functioning, there is a need for research [10] one-dimensional and phenomenological MM, a combination of experimental studies are used effectively in solving complex practical problems. This is characteristic of preliminary evaluation on the efficiency of an operating DE fleet models, functioning of NG transfer, there is a lack of initial data for an efficient use of multi-dimensional models. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 407–414, 2020. https://doi.org/10.1007/978-3-030-38666-5_43

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In practice, the mathematical modelling of parameters for the DE conversion to DF is largely done using multi-dimensional MMs. However, in the initial phase of engine conversion MM, there is a lack of data as well as a need for a preliminary assessment. Which makes it appropriate to use one-dimensional MM. This MM method is widely adapted to the research of different aspects of DE. However, the applicability of these MMs for DF engine research and evaluation of the results obtained is lacking in the literature. On this basis, the objective of this research became the use of a one-dimensional mathematical model for DF engine MM using the IMPULS software package. One of these tasks was solved by researchers from Klaipeda University (KU) and Vilnius Gediminas Technical University (VGTU), carrying out research on a highspeed converted 4-cylinder ICE 79.5/95.5 that was operating on dual-fuel D/NG. The aim of research presented in this publication was to evaluate the possibilities of using one of the one-dimensional MM’s in IMPULS software for programming energy efficiency indicators of a conventional fuel injection system, while operating in a wide range of modes. Also taking into account optimization of the pilot fuel portion injection angle. Evaluation criteria were established by using the results from engine’s propulsion, energy, ecological and indicator process characteristics.

2 Experiment Methodology and Equipment The results of the change in engine performance in D and DF modes are the differences in the physical processes in the cylinder. The induction period remains actually unchanged, as in both cases, the combustion begins with the ignition of diesel fuel. However, the dynamics of the combustion process are different. The diesel engine is powered by traditional bi-phase (kinetic and diffuse) combustion, in the diesel fuel jets in the environment. Dual fuel burning is prolonged because the combustion of gaseous fuel is formed by flame spreading to all cylindrical areas, including the periphery. This process is prolonged in the practice of a uniform swirl movement of the working material in the cylinder (assessing pas and Tas ¼ invar). As a result, when comparing the actual temperature of the simulated combustion products, there was a rather large discrepancy that forced the use of bi-phase MM instead of a single-phase MM. In the numerical experiment, a one-dimensional mathematical model with a formalized analytical expression of heat release was used [10]. The mathematical model implements modelling of four-stroke and two-stroke diesel engine cycle parameters on a closed energy balance basis. In large part, heat dissipation in cylinder, which determines the accuracy of the simulation, is given by a one-dimensional I. Vibe model with G. Woschni’s modifications: "
m þ 1 #
a2

 u u pas Tas0 n0 a1 X ¼ 1  exp 6908 ; ; m ¼ m0 i0 uz ui p Tas n ð1Þ a a3 n a4 0 0 uz ¼ ; a n

Adapting a One-Dimensional Mathematical Model

409

where u is the current angle of the cycle, calculated from the start of the heat release for the conversion of the form factor m and the relative duration uz to the partial load engine operating modes used by Woschni’s analytical dependencies [11, 12]; a1 ; a2 ; a3 ; a4 – constants; ui – self-ignition induction period; pas and Tas – cylinder air charge pressure and temperature; n – engine speed; a – excess air factor. The object of research was high-speed diesel engine DE with conventional fuel injection system 4ČN 79,5/95,5. The main specific parameters of DE are presented in Table 1.

Table 1. Engine specification. Model Displacement, (cm3) Bore/Stroke, (mm) Maximum power, (kW/rpm) Maximum torque, (Nm/rpm) Cooling type Fuel supply system Cylinders Compression ratio Aspiration

4ČN79,5/95,5 1896 79.5/95.5 66/4,000 180/2,000–2,500 Water cooling Direct injection 4 in line 19.5:1 Turbocharged

Numerical tests have been performed with the engine running at high load mode HLM ðpmi ¼ 8; 2 barÞ and low load LLM ðpmi ¼ 4; 2 barÞ using diesel D and combination of diesel D with natural gas NG (D20/NG80) during DF mode.

3 The Experiment Results and Discussion In the initial stage of research, the mathematical  model was combinedwith the object under investigation in its HLM with diesel fuel uinj ¼ 13 CA BTDC . The constants used in the mathematical model algorithm, including the characteristics of the turbine unit in the Woschni equations, were left unchanged in the modelling of the engine parameters in MLM and LLM modes, changing uinj in the range −1–−13°CA BTDC (see Fig. 1). The main engine parameters modelling error does not exceed 15% in the whole studied range, averaging 2.5–8%, and testifies to the good compatibility of the mathematical model with further D-NG fuelling in subsequent engine tests.

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Fig. 1. Comparison of engine 4ČN 79,5/95,5 functioning with diesel fuel experimental and mathematical modelling main indicators charts: (a) D100=30 Nm=uinj ¼ 1 CA BTDC; (b) D100=90 Nm=uinj ¼ 1 CA BTDC.

The HLM modelling and experiment parameters error does not exceed 7%, see Table 2. In partial load modes, MLM and LLM modelling error is 20–50% (see Table 3). It should be emphasized that the most important energy parameters during these modes Pme ; Pmi ; ge ; gi reaches discrepancy from 15–52%.

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Table 2. Comparison of the experimental and mathematical model results of 4ČN 79,5/95,5 engine operation during DF D20/NG80 HLM mode regime, n ¼ 2; 000 min1 . 13 CA Error, % 1 CA Error, %

Pk ; bar

a

Tt , °C

Tk , °C

Pme ; bar

Pmi ; bar

ge

gi

1.35/1.35 0 1.47/1.44 −2.1

2.54/2.67 +5.1 2.30/2.41 +4.78

661/686 +3.6 750/808 +7.18

333/324 −2.8 343/342 −0.3

5.964/5.71 −4.5 5.964/6.00 +0.6

8.204/7.82 −4.9 8.204/8.14 −0.8

0.366/0.333 −10.0 0.288/0.310 +7.1

0.462/0.456 −1.3 0.396/0.417 5.0

Table 3. Comparison of the experimental and mathematical model results of 4ČN 79,5/95,5 engine operation during DF D20/NG80 MLM and LLM mode regimes, n ¼ 2000 min1 . , bar = 3.99 error % = 1.98 error, %

,℃

1.38/

2.57/

661/793

1.36

2.54

-1.5%

-1.2%

+16.6

1.25/

2.93/

571/720

1.28

3.0

+2.3

+2.4

+20.7

,℃ 329/336

, bar

, bar

, bar

57.8/

3.976/

6.242/

0.218/

0.342/

74.1

5.18

7.32

0.293

0.415

+2.1

+22.0

+23.0

+14.7

+25.6

+17.6

319/325

50.1/

1.988/

4.194/

0.131/

0.275/

70.5

4.1

6.25

0.27

0.424

+29.0

+51.5

+32.9

+51.5

+35.1

+1.8

We note that such a large difference in indicators has been obtained under practically uniform conditions of engine cycle: ud:pr: , Pk , Tk , ui , qcikl . On this basis, it is hypothesized that the deviations of the modelling results in the MLM and LLM working modes are related in part to the loss of gaseous fuel during the purging of cylinder. In high load modes ðPme  5:97 I Þ, the amount of gaseous fuel lost is not relatively high, but its value in low load modes ðPme  1:98 barÞ is considerably higher. On the other hand, the significant decrease of ge and gi parameters MLM and LLM is related with NG combustion duration time increase. Assessing the measurement of the harmful emission components, the Cn Hm components in the exhaust gas do not exceed – 42 g/h in MLM mode, and in LLM mode – 60 g/h, respectively 1.3% and 2.2% of the NG spent in dual fuel D20/NG80. On the other hand, a significant increase in the duration of the heat dissipation characteristic by transferring the engine to D20/NG80 is confirmed by the results of the experiment. For example, the 50% phase  CA50 of the heat release of fuel combustion in HLM mode extends until the 4 CA meanwhile in both MLM and LLM it increases 12 CA and 42 CA respectively. The results of indicated engine process modelling also confirms this. Matching mathematical model with experimental data by Bulaty and Glanzman [13]. Individual m and uz values were set for each mode: during HLM m ¼ 0:8, uz ¼ 50; MLM m ¼ 0:7, uz ¼ 44 and in LLM m ¼ 0:64, uz ¼ 35 for engine functioning with diesel fuel.

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Unlike the engine functioning with diesel fuel, in DF mode, when load decreases from HLM uz rise to 65 CA, and during MLM and LLM modes uz increases to 110 CA and 200 CA respectively, while excess air coefficient a respectively increased from 2.0 to 2.55 times. When engine is running on diesel fuel, uz decreases when increasing a part in load modes, with gi increasing, respectively. Obvious discrepancy between uz values obtained on the basis of experiment and analytical expression [11, 12, 14, 15]. Therefore, the analytical method of determining uz in DF engines requires improvement. The explanation is based on results from many experimental studies [16, 17]. It has been found that after the kinetic phase of HRF, the next phase of combustion consists of NG combustion by the diffusion mechanism. In this phase, the intensity of NG combustion depends on the position of active radicals OH in the volume of the cylinder. In the absence of sufficient time to prepare for the combustion phase, that is, the ignition delay dependency induced with diesel injection advancement, the NG combustion process extends. Table 4 shows the parameters of the 4ČN 79,5/95,5 engine when operating on DF D20/NG80 mode, modelling results, using the obtained m and uz correlations with a; Pa ; Ta ; n parameters dependency adjusted values.

Table 4. Mathematical modelling results of engine 4ČN 79,5/95,5 operated on DF D20/NG80   mode indicators, using the revised m and uz parameters uinj ¼ 13 CA BTDC . = 5.97 bar

Load mode Research

EXP.

MM

, g/cikl 0.0169 0.0169 , MJ/kg , bar ,K , bar

= 3.99 bar EXP.

MM

0.0143 0.0143

= 1.98 bar EXP.

MM

0.01255 0.01255

48.33

48.33

48.48

48.48

48.55

48.55

1.35

1.35

1.25

1.25

1.175

1.175

333

333

318

318

315

315

100.6

100.0

79.0

76

67.3

66.3

0.345

0.345

0.273

0.276

0.155

0.157

0.475

0.473

0.433

0.438

0.330

0.333

0.726

0.730

0.630

0.630

0.470

0.470

, bar

5.95

5.96

3.97

4.05

1.98

2.00

, bar

8.20

8.17

6.30

6.40

4.20

4.28

2.54

2.23

2.95

2.49

3.19

2.71

The modelling showed that the (Pmax ; ge ; gi Pme ; Pmi and etc.) parameter data correlate well with the test results, in Table 4 they are marked in green. Except for the  exhaust gas temperature Tg , the obtained energy parameters ðPmax ; gi ; ge ; Pmi ; Pme Þ of the engine were sufficiently accurate 3–5% when compared to the experimental data.

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For a comprehensive use of the one-dimensional mathematical model for research, rational application of the bi-phasic I. Vibe law. Simulation with one-dimensional models can be rationally combined with statistical experimental data. In particular with correlated graphical dependencies of ðgi ¼ f ðX; Pe  idemÞÞ see Fig. 2. 0.6

ηi 0.55

R² = 0.9519

R² = 0.7988

R² = 0.9938

0.5 0.45 0.4

Pmi = 4,2 bar

0.35

Pmi = 6,24 bar Pmi = 8,2 bar

0.3 0.25 1.5

2

2.5

3

3.5

α

4

4.5

5

5.5

6

Fig. 2. DF engine parameters gi and a dependency from each other between different loads, CCR NG and uinj (CCR NG = 0–0.8; uinj ¼ 1  13 CA BTDC).

For example, in order to determine the indicated energy efficiency ðgi Þ of engine in a particular load mode ðPe  idemÞ it is sufficient to evaluate ðaÞ. The rational DIT phases are chosen during modelling.

4 Conclusions Performed research shows limited possibilities for simulating a single mathematical model with formalized heat release characteristics for simulating dual D/NG fuel 4ČN 79.5/95.5 engine indicator process: 1. In high engine load mode HLM mathematical modelling results of efficiency parameters, had acceptable low error of 5% and matched well with experimental data. 2. In dual fuel D20/NG80 medium MLM and low LLM modes results were achieved by combining mathematical model parameters individually for each mode. Unlike engine operation with diesel fuel, in DF D20/NG80 partial load MLM and LLM modes combustion time significantly increased: from 65 CA HLM 41% and 68% to 110 CA and 200 CA respectively. The results are fundamentally contrary to the conversion factors of m and uz of the one-dimensional diesel mathematical model of combustion. Therefore, it is expedient to rely on the analytical expression of a biphasic heat release characteristic for the practical use of a one-dimensional mathematical models.

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3. With acceptable error of 5–7% the use of a one-dimensional mathematical for optimization of the HRF (D) injection phase in the range from 1  13 CA BTDC is rational. On this basis, it is recommended to use the investigated mononuclear model and the statistically summarized experimental data (example: gi ¼ f ðX; Pe  idem), as well as the characteristics of biphasic heat release I. Vibe adaptation, for practical use.

References 1. Marpol 73/78 Annex VI- Regulations for the Prevention of Air Pollution from Ships. Det Norske Veritas (DNV), DNV, Norway (2008) 2. IMO: Greenhouse Gas Emissions (2013). http://www.imo.org/OurWork/Environment/ PollutionPrevention/AirPollution/Pages/GHGEmissions.aspx. Accessed 26 Mar 2013 3. Maurya, R.K., Mishra, P.: Parametric investigation on combustion and emissions characteristics of a dual fuel (natural gas port injection and diesel pilot injection) engine using 0-D SRM and 3D CFD approach 4. Arteconi, A., Brandoni, C., Evangelista, D., Polonara, F.: Life-cycle greenhouse gas analysis of LNG as a heavy vehicle fuel in Europe. Appl. Energy 87, 2005e13 (2010) 5. Maghbouli, A., et al.: Numerical study of combustion an emission characteristics of dualfuel engines using 3D-CFD models coupled with chemical kinetics. Fuel 106, 98e105 (2013) 6. Günter, P., et al.: Simulation of Combustion and Pollutant Formation for EngineDevelopment. Springer, Heidelberg (2006) 7. Liu, J., et al.: Experimental and numerical study of the pollution formation in a diesel/CNG dual fuel engine. Fuel 159, 418–429 (2015) 8. Rapalis, P., et al.: Comparative analysis of diesel engine mathematical modelling packages for practical use on transport diesel engine operating on biodiesel, pp. 173–178 (2013). https://doi.org/10.3846/transbaltica2013.038 9. Lebedevas, S., Lebedeva, G.: Mathematical model of combined parametrical analysis of indicator process and thermal loading on the diesel engine piston. Transport 3, 108–118 (2004). ISSN 1648-4142 10. Ивaнчeнкo, К.H. и дp.: Bыcoкий нaддyв дизeлeй, Л.: Maшинocтpoeниe, 198 p. (1983) 11. Woschni, G.: Die Berechnung der Wandverluste und der thermischen Belastung von Dieselmotoren. MTZ 31 (1970) 12. Woschni, G., Anists, F.: Eine Methode zur Vorausberechnung der Änderung des Brenverlaufs mittelschnellaufender Dieselmotoren bei geanderten Betriebsbedigungen. MTZ 4, 106–110 (1973) 13. Bulaty, T., Glanzman, W.: Bestimmung der Wiebe – Verbrennungsparametr. MTZ 7–8(45), 299–303 (1984) 14. Wiebe, I.I.: Brennverlauf und Kreisprozesse vonVerbrennungsmotoren, 280 p. VEB Verlag Technik, Berlin (1970) 15. Bибe, И.И.: Hoвoe o paбoчeм циклe двигaтeлeй. Mocквa-Cвepдлoвcк: Maшгиз (1962) 16. Faghani, E., Kheirkhah, P., Mabson, C.W., McTaggart-Cowan, G., Kirchen, P., Rogak, S.: Effect of injection strategies on emissions from a pilot-ignited direct-injection natural-gas engine-part II: slightly premixed combustion. In: SAE Technical Paper. SAE International (2017). http://dx.doi.org/10.4271/2017-01-0763 17. Wang, T., Zhang, X., Zhang, J., Hou, X.: Numerical analysis of the influence of the fuel injection timing and ignition position in a direct-injection natural gas engine. Energy Convers. Manag. 149, 748–759 (2017)

Building on a Traffic Code Violating Monitor for Autonomous Vehicles: Trio Overtaking Model Dan M. Costescu1,2(&) 1

FIRST-Romanian Institute for Safety in Transportation Bucharest, Bucharest, Romania [email protected] 2 University Politehnica of Bucharest, Spl. Independentei 313, Bucharest, Romania

Abstract. The present study aims at filling the gap between the existing traffic regulation and the technical specification for construction or behavior in operation of autonomous vehicles. The former is provided in generic and often complicated texts as the lawyers tend to cover with a single formulation all possible cases, including those not yet identified. On the contrary, for the latter, the engineers need to identify any possible situation in advance and produce precise instructions to assess, approach and deal with it, to be embedded in the safety and security logic of the self-driving vehicle. The author builds on his previous work regarding the formalization of traffic code from the natural language to computer language, in a three steps methodology including Legal, Logic and Engineering Analyses. The previous development on Logic Analysis was extended with the multi-level hierarchy of predicates and their interpretation for Perform-Overtaking phase and with their associated Linear Temporal Logic (LTL) Formulas. This codification prepared the ground for the Engineering Analysis where the Trio Overtaking Model (TOM) was developed, considering the influence of the forerunner car over the dynamics of Overtaking (Autonomous) and of overtaken vehicle. As a premiere for three vehicle case, 25 combined scenarios were defined as matrix and for their analysis, the formal definitions, theorems, Collision Matrix and the Safe Distance Matrix were introduced. Applications for runtime checking and monitoring, synchronous (runtime enforcement) and asynchronous (e.g. black box analyze) within a Traffic Code Violating Monitor, were proposed. Keywords: Self-driving vehicle Traffic code violation monitor


Trio Overtaking Model
Logic analysis


1 Introduction Legal accountability of autonomous vehicles (AV), the way these are conditioned to obey the Traffic Code or other safety and security regulations, appear to gain an increasing importance for both authorities and industry. While the formers are concerned mostly about keeping their citizen safe or giving to enforcement bodies the © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 415–426, 2020. https://doi.org/10.1007/978-3-030-38666-5_44

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appropriate instruments for traffic monitoring or accident investigation [1], the manufacturers aim to take advantage through AV innovative technology over competition, by integrating safety and security with their customer experience centered offer [2]. The traffic rules against the drivers are today kept liable, are expressed making use of specific legal terms and syntax, being in fact subspecies of the natural language, appropriated for communication between individuals but improper for immediate development of the computer code required by AV automation. Legal texts like “Return to initial lane or row of vehicles after making sure such a maneuver is safe for all road users.” - R. Art. 118. (d) Traffic Code [3] include many challenges when try to implement them in terms of time, position, speed and acceleration which are describing the motion of the self-driving vehicle. That gap between these different approaches, domain specific, can be filled by the rules formalization whose foundation has developed [4] by introducing the codification and concretization concepts. The methodology evolved and consolidates now three analyses types: Legal, Logic and Engineering Analyses. The first two were detailed in [5] and the present paper is a development and continuation of it, aiming to contribute on Engineering Analysis of some aspects related to overtaking, involving autonomous vehicles, not yet covered by literature.

2 Planned Work The findings of Legal Analysis from author’s previous work will be hereafter used, as resulted from applying the methodologies for eliminating the inherent redundancy of related legal regulations, unequivocally separation of user’s and AV’s responsibilities and their logic breaking down in “predicate precursors”. Then, as Logic Analysis was conceived for bridging legal and engineering aspects, for the particular case of Overtaking the Modal Logic Flow Chart will be used. This chart, where the process was sequenced but the events are still untimed, defines the following phases of the maneuver: (i) Detecting-Need & Type-of-Overtaking, (ii) Pre-Check-Overtaking and (iii) Perform-Overtaking. On this basis, considering the Temporal Logic Diagram (see Fig. 1), that assigns time intervals [t0, t3], [t3, t5] and respectively [t5, t9] for the above defined phases; a multi-level hierarchy, Atomic Proposition Table for the latter will be developed and the Linear Temporal Logic (LTL) Formulas will be deduced accordingly. After that improvement on automation, the expressivity for a proper High Order Logic (HOL) formulation should be assured as well during next steps. This is, employing the Engineering Analysis for concretization (expressing in terms of position, speed and acceleration) of an Overtaking involving three vehicles, where at least one vehicle is autonomous. The principal and ancillary predicates and variables will be defined and the combined braking scenarios for three vehicles will be introduced, based on the motion equations associated to every vehicle. The collision matrix and safe distance matrix will be developed for a synthetic analysis of the combined scenarios and then, scenario specific theorem will be proposed to solve the problem of simultaneously assessing safe-distance-rear and safe-distance-front predicates which is actually, the Trio overtaking problem.

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3 Logic Analysis If both the preliminary formulas, Detecting-Need & Types-of-Overtaking and PreCheck-Overtaking [5] were assessed as true, meaning an overtaking is requested, its type is known, and safety requirements are fulfilled for both infrastructure and other users, then AV can approach the last stage of overtaking and engage in the specific maneuvers. The multilevel hierarchy of predicates [6] is proposed and logically interpreted in Table 1. Table 1. Atomic propositions, levels and interpretations for Perform-Overtaking. Level

Time

1. 2. 2.

t5 –t9 t5 –t6 t6 –t7

Atomic Propositions (AP) Perform-Overtaking Signaling Start-Overtaking

t7 –t8

Do-ChangeDirection Do-Leave-Initial(Lane/Vehicle-Row) (Keep) Signaling Advance-Overtaking

3. 3. 3. 2. 3.

3.

Safe-LateralDistance (Keep) Signaling CompleteOvertaking Safe-Distance-Rear

3.

Safe-Distance-Front

3. 3.

Signaling Do-ChangeDirection Do-Return-ToInitial(Lane/Vehicle-Row)

3. 2.

3.

t8 –t9

Logic interpretation Execute the complete overtaking maneuvers Activate the blinker Move from the initial trajectory to the overtaking trajectory Gradually change direction to leave the initial trajectory Move from initial lane or vehicle row until a safe lateral distance to the overtaken vehicle is attained Maintain the blinkers on Run along the overtaking trajectory with a higher speed than overtaken vehicle Maintain a safe distance between the Ego and the overtaken vehicle Keep the blinker on Move from the overtaking trajectory to the initial trajectory Check if the distance to the overtaken vehicle is safe to return in front of him Check if the distance to a vehicle running in front of overtaken vehicle is safe to return behind of him Activate the other blinker Gradually change direction in order to left the overtaking trajectory Return to initial trajectory, in front of the overtaken vehicle

The resulted LTL formulas of relevant traffic rules [3] for Perform-Overtaking, after compounding the above described atomic propositions using Boolean operators, are described below, over the time interval ½t5 ; t9  of the Temporal Logic Diagram as:

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1. Intention of road users to change the running directions, to leave or enter a row of vehicles, to change the lane or (…) must be signalized by turning on the blinking lights with at least 50 m within urban areas and at least 100 m otherwise, before starting the maneuver - R. Art 116 (2): F ð56Þ ¼ f ðSignalingÞ;

ð1Þ

where F ð56Þ is the logic formula valid between the time points [t5, t6]; f ðAPÞ – the function assessing the atomic proposition AP always as true. 2. One vehicle passes another vehicle or an obstacle that is on the same lane - Art 45, (1.1.1). & (1.1.2) by changing the running direction and leaving the initial lane or row of vehicles. - Art 45 (1.1.1.1; 1.1.1.2; 1.1.2.1; 1.1.2.2): F ð67Þ ¼ f ðStartOvertaking ! ðSignaling ^ ððDoChangeDirection ^ DoLeave InitialLaneÞ  ðDoChangeDirection ^ DoLeaveInitialVehicleRowÞ

ð2Þ 3. Signalization of any change in running direction shall be maintained during the entire duration of the maneuver - Art 54(2) and the vehicle shall keep during the maneuver an enough lateral distance to the overtaken vehicle - R. Art 118(c): F ð78Þ ¼ f ðAdvanceOvertaking ! ðSignaling ^ SafeLateralDistanceÞ ð3Þ 4. Return to initial lane or row of vehicles after making sure such a maneuver is safe for all road users - R. Art. 118(d): F ð89Þ ¼ f ðCompleteOvertaking ! ðSignaling ^ DoChangeDirection ^ ðDo ReturnTo InitialLane  DoReturnTo InitialVehicleRowÞÞÞ ! ðSafeDistance Rear ^ SafeDistanceFrontÞ

ð4Þ

Fig. 1. Temporal logic diagram.

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4 Concretization of Overtaking Elements The resulted logic codification in LTL helps through its simplicity to automation process [7] but it is not enough expressive to formalize alone the traffic rules and to allow their fully automated checking. Expressivity will be enhanced by continuing the above legal analysis with an engineering analysis aiming to further develop the LTL’s predicates into HOL language [8]. This is, concretely expressing the legal atomic propositions defined in Table 1 and resulted logical formulas, in terms of specific actions, position, speed and acceleration for AV. Literature treated some basic elements of AV overtaking such as detecting of the lane changing [9] or defining and controlling of the optimal trajectory [10] but most of these are simplified cases of the real situation such as, involving only two vehicles, or highway scenarios where usually no pressure to return to initial lane exists. Aiming to bring the concretization closer to the real world, the influence of the other vehicles running in the same direction or from the opposite direction should gradually be added on the foundation of above-mentioned developments. In this regard the author proposes the concretization of the situation where the Ego (self-driving) vehicle taking over the vehicle V1, shall also consider the other vehicle V2 running initially in the front of V1 at the distance d12. That minimal distance should be assessed in order to allow Ego vehicle, just returned to the vehicles row in front of V1, after completing overtaking, and behind of V2, to safely deal with an emerging braking of V2. The methodology for eliciting d12 applies with slight adjustment, either for the concrete case when assessment starts at the moment Ego already took over V1 (the usual highway case) or starts during the Pre-Check procedure, before Ego to initiating the maneuver, where the result should be anyway correlated with the information about traffic from opposite direction (the usual case for regular roads). However, as it be discussed later, it could be also integrated in a runtime procedure, monitoring, from the beginning to the end of overtaking, the safe distance d12 between the vehicles V1 and V2. Resuming, the aim is to formalize the R. Art. 118 (d), already expressed by Eq. (4) in LTL. Figure 2 is used for concretization of (Safe-Distance-Rear ˄ Safe-DistanceFront) which is actually the initial condition required by the logical implication defining the Complete-Overtaking.

Fig. 2. Concretization of (Safe-Distance-Rear ˄ Safe-Distance-Front).

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The position of Vego, the black car in Fig. 2, related to the moment immediately after completing the overtaking, will be used for following definitions: Definition 1: For two vehicles Vi and Vj having the motion equations {di(t), dj(t)}, and a finite time domain TD := [0, tlim] that could be eventually extended for a continuous run to an infinite time domain TD := [0, ∞], we define the predicate avoid-collision (TD) := di(t) 6¼ dj(t) 8 t 2 TD; where the vehicles are considered idealized to the foremost point of the follower Vi and to the rearmost point of the forerunner Vj. This is, the curves representing the motion equations of the two vehicles never intersects on the defined time domain or in other words, there is no such a moment over the TD when the vehicles are at the same coordinates (collides). Definition 2: For two vehicles Vi and Vj and their positions {si,t, sj,t} at the moment t, for an elemental scenario k 2 ½1. . .n generated by different combinations of speeds {vi, vj} and accelerations {ai, aj}, we define the safe-distance as SDi,j(k) := sj,t − si,t. This is the initial distance (at the assessment moment) between vehicles, required to assess the predicate avoid-collision always as true, given the motion equations {di(t), dj(t)} of vehicles during braking. For the present paper, the assessment moment is that when the Vego just returned in the row with V1 and V2, between them and V2 starts to brake (d12 is represented as SD1,ego,2 in Fig. 2). The braking equations of vehicle 2 (V2), supposing to initiate first the braking at the moment t0 is:
d 2 ðt Þ ¼

d2;0 þ v2 t þ 0:5a2 t2 2 d2;0 þ v2 t2;stop þ 0:5a2 t2;stop

for 0  t  t2;stop for t  t2;stop

ð5Þ

where d2;0 – the initial position of V2 at the moment t0; v2 – speed of V2 at the moment t0; a2 – acceleration of V2 at the moment t0; t2;stop – time to stop of V2. The braking equations of Ego vehicle (Vego), formula [6]: 8 < dego;0 þ vego t; for 0  t sego  2 dego ðtÞ ¼ dego;0 þ vego tþ 0:5aego t sego ; for sego  t  sego þ tego;stop : 2 dego;0 þ vego sego þ tego;stop þ 0:5aego tego;stop ; for t  sego þ tego;stop

ð6Þ

where dego;0 – the initial position of Vego at the moment t0; sego – reaction time of Vego; vego – speed of Vego at the moment t0; aego – acceleration of Vego at the moment t0; tego;stop – time to stop of Vego. And the braking equations of vehicle 1 (V1) is: 8 < d1;0 þ v1 t; for 0  t  sego þ s1  2 d1 ðtÞ ¼ d1;0 þ v1 tþ 0:5a1 t  sego  s1 ; for sego þ s1  t  sego þ s1 þ t1;stop : 2 d1;0 þ v1 sego þ s1 þ t1;stop þ 0:5a1 t1;stop for t  sego þ s1 þ t1;stop ð7Þ where d1;0 – reaction time of V1; s1 – speed of V1 at the moment t0; v1 – acceleration of V1 at the moment t0; t1;stop – time to stop of V1.

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The braking ways (BW) of the vehicles result by zeroing the derivatives of the above defined braking equations: 8 @d ðtÞ 2 > < @t ¼ 0 @dego ðtÞ ¼0 @t > : @d1 ðtÞ @t ¼ 0

ð8Þ

8 v2 > BW2 ¼ d2;stop ¼ d2;0  0:5 a22 > < v2 BWego ¼ dego;stop ¼ dego;0 þ vego sego  0:5 aego ego > >   : v21 BW1 ¼ d1;stop ¼ d1;0 þ v1 sego þ s1  0:5 a1

ð9Þ

and that gives:

Rizaldi et al. [9] identified five possible elemental scenarios (see Table 2) when studied two vehicles braking (Duo), meaning that n = 5 in definition 2 for Duo. This is when the first vehicle in row, V2, initiates the braking from the position d2;0 , the Ego vehicles, second in row, could brake according to one of the five curves starting from position dego;0 . Table 2. Collision elemental scenarios for overtaking considering two vehicles Vi and Vj. Scenario Description of stopping position for vehicle Vi - follower (having a reaction time ) relative to the position of Vj - forerunner, that brakes first I Vi stops before the starting point of Vj braking II Vi stops after starting point of Vj braking but before its position at III IV V

Colour Green Blue

Yellow Vi stops after position of Vj at but before its stopping point Vi stops after the stopping point of Vj - collision! Red Vi is at , before starting braking, already in front of Vj – collision! Magenta

Moving back to the newly introduced case of three vehicles (Trio) overtaking V1, Vego, V2, (see Table 2), the number of the combined scenarios to be analyzed increases to n = 53−1 = 25 as combination of the before defined duo scenario. Considering the possible sets of braking cases for every vehicle, it results: 8 < V1 ¼ fd2 g  Vego ¼ dego ðI Þ; dego ðII Þ; dego ðIII Þ; dego ðIV Þ; dego ðV Þ : V2 ¼ fd2 ðI Þ; d2 ðII Þ; d2 ðIII Þ; d2 ðIV Þ; d2 ðV Þg

ð10Þ

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The combined braking scenario matrix [CBS] can be defined as: ½CBS ¼ aij ; where aij ¼ d2 ^ dego ðiÞ ^ d1 ð jÞ for i, j ¼ 1. . .5:

ð11Þ

As can be observed in Fig. 3, the combination involving at least one of the elemental scenarios IV or V leads to collision. For the case IV the follower vehicles intercept the forerunner vehicle before the latter stop, and for the case V even before the former begins to brake (within its reaction time).

Fig. 3. Graphic representation of braking equation for vehicles V1, Vego, V2.

The collision matrix is defined as: C ¼ ½cij ; for i, j ¼ 1. . .5;
where cij ¼

0; if scenario ai;j does not lead to collision; 1; if scenario ai;j does lead to collision:

ð12Þ

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Then the collision matrix is:  0  0  ½C ¼  0 1  1

0 0 0 1 1

0 0 0 1 1

1 1 1 1 1

 1  1  1 : 1  1

ð13Þ

For the 16 elements, cij having value 1, the collision is taking place and the problem reduced to determine its moment and position from the motion equations. For the rest of 9 elements, cij having value 0, the collision could be avoided when a safe distance, as further defined, is provided. Definition 3: For a vehicle Vego of length Lego that should return after overtaking vehicle V1 to the initial vehicles row, behind of vehicle V2, we define the Safe-DistanceEgo-1-2 for the combined scenario aij as distance between V1 and V2 at the moment when Vego completed the return: sd1;ego;2 ði; jÞ ¼ SDego;2 ðiÞ þ Lego þ SD1;ego ð jÞ for i, j = 1…5, where the elemental safe distances SDego;2 and SD1;ego are calculated according to Definition 1. Consequently, the Safe-Distance-1-Ego-2 matrix could be introduced as:   sd1;ego;2 ð1; 1Þ     sd1;ego;2 ð2; 1Þ SD1;ego;2 ¼  sd1;ego;2 ð3; 1Þ  1   1

sd1;ego;2 ð1; 2Þ sd1;ego;2 ð2; 2Þ sd1;ego;2 ð3; 2Þ 1 1

sd1;ego;2 ð1; 3Þ sd1;ego;2 ð2; 3Þ sd1;ego;2 ð3; 3Þ 1 1

1 1 1 1 1

 1  1  1 : 1  1

ð14Þ

 The non-trivial elements of SD1;ego;2 are separately elicited, expressing specific theorems that can be proved by a HOL theorem prover as Coq, Metamath, HOL4 or Isabelle. The elements related to collision cases were conventionally assigned to 1 distance. For brevity only, the approach for sd1;ego;2 ð1; 1Þ is presented here below. Theorem 1: ðdego;stop \d2;0 Þ ^ ðd1;stop \dego;0 Þ ¼ [ ðavoid  collisionðTDÞÞ. That is, for the combined scenario aij and over the time domain TD, the Vego always stops before the position where V2 initiated braking and V1 always stops before the position where Vego initiated braking. Expressing dego;stop and d1;stop according to Eq. (9) and using then Definition 3, the Safe-Distance-1-Ego-2 for the first scenario a11 is: sd1;ego;2 ð1; 1Þ ¼ vego sego  0:5

  v2ego v2 þ Lego þ v1 sego þ s1  0:5 1 : aego a1

ð15Þ

 Once the elements of SD1;ego;2 are calculated for a set of three vehicles experiencing an overtaking changing the sequence (Vego V1 V2) in (V1 Vego V2), that could be easily applied to the more general problem of a vehicle Vego approaching a vehicles row (V1…Vn) with the aim to overtake them one by one or batch by batch.

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In other words, the legal text regarding the safe return after overtaking was interpreted in terms of time, position, speed and acceleration sets, assigned to every vehicle belonging to {Vego, V1, …, Vn}, n = 1… 1 and the proposed goals of formalization were achieved.

5 Traffic Code Obeying Analyzer Concretization was the last necessary step to building the Code Violating Monitor (CVM) a tool capable to either a priori check [11] the conformity of AV’s microrouting proposals with the relevant traffic code, before initiating any vehicle movement, or a posteriori checking [12] of an already performed AV’s path, against the relevant traffic rules. The former application is conceived to work as a built-in runtime monitoring procedure, validating in advance from the legal point of view, any command to be delivered by the AV’s central unit to the controllers and then to the actuators (engine, brake, steering). It is worth mentioning that for well justified situations, legally nonvalidated commands could be still executed (e.g. when an ethical reason prevails over a “harmless” traffic rule violation). The latter application can be employed as an external checking tool or asynchronous monitoring [13], assessing the conformity with the traffic code of an already executed maneuver as recorded by black-boxes or similar devices storing log files [14]. This is useful to enforcement or investigation bodies for accidents analyses or reconstruction.

6 Conclusions and Future Work The Traffic Code Violating Monitor was proposed aiming to keep the autonomous vehicles accountable against the traffic rules. Usually these rules are consolidated in National Traffic Codes and approved as laws by the authorities, being therefore expressed using legal specific terms, syntax and semantic which improve the precision comparing with natural language but not enough to allow an immediate automation. The previous work on Logic Analysis was extended with the multi-level hierarchy of predicates and their interpretation for Perform-Overtaking phases and the associated Linear Temporal Logic (LTL) Formulas. After facilitating a better automation through the logic analysis of overtaking rule, the still missing expressivity has been enabled by Engineering Analysis (Concretization). The author developed the Trio Overtaking Model for three vehicles, by considering the influence of the forerunner car over the dynamics of overtaking and overtaken vehicle. In order to elicit the Safe-Distance-1-Ego-2 required by the Ego to safely return between vehicles V1 and V2 when completing the overtaking, 25 combined scenarios were defined as matrix and also the Collision matrix, Safe Distance matrix and individual theorems, all for Trio scenario were introduced.

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The safe distance matrix defined for trio is actually a generalized formulation of studied maneuver as the Ego vehicle can actually initiate on its basis the overtaking of an infinite long vehicle’s row, displaying different sets of {time, position, speed, acceleration}. The developed model is usable for runtime verification that allows checking whether the AV under scrutiny satisfies or violates the set of correctness properties imposed for Trio overtaking. Monitoring could be implemented, by developers of AV, only in detection mode (passively recording the events and their assessment) or in runtime enforcement mode (getting actively involved in AV execution by stopping or changing it). Investigation bodies may also take advantage of the methodology when analyze or reconstruct accidents in checker mode (asynchronous monitoring). Future work will consider the AV engineering analysis of the safe-distance (-rear/front) as a function of moment/position the assessment is done (e.g. calculate the required distance between V1 and V2 even from the moment Vego is still behind V1). A major step forward would be also the concretization of the Safe-Distance-IncomingTraffic predicate, which will allow overtaking execution not only in simplified environment as highways but on regular roads as well. On this basis some challenges of today AV’s development become more approachable in the future. This is, planning, monitoring or checking of Vego when predicted or monitored situation suddenly experience a critical change during execution or when a mixed traffic with non-AV vehicle asks for considering the human behavior and reactions.

References 1. NHTSA: Preliminary Statement of Policy Concerning Automated Vehicles. National Highway Traffic Safety Administration Report (2016) 2. Lohmann, R., Van der Zwaan, S.: Regulations required: safety drives autonomous vehicles market. 2getthere White Paper, Utrecht, The Netherlands (2018) 3. Ursuta, M.: Codul Rutier. Universul Juridic, Romania (2016). (Traffic Code of Romania) 4. Rizaldi, A., Althoff, M.: Formalizing traffic rules for accountability of autonomous vehicles. In: IEEE 18th International Conference on Intelligent Transportation Systems (ITSC), pp. 1658–1665 (2015) 5. Costescu, D.M.: Keeping the autonomous vehicles accountable: legal and logic analysis on traffic code. In: Conference Vision Zero for Sustainable Road Safety in Baltic Sea Region, Vilnius, 5–6 of December 2018. Springer (2019) 6. Ben Ari, M.: Mathematical Logic for Computers. Springer, London (2012) 7. Benzmueller, C., Miller, D.: Automation of higher-order logic. In: Gabbay, D.M., Siekmann, J., Woods, J. (eds.) Handbook of the History of Logic. Computational Logic, vol. 9. Elsevier, North Holland (2014) 8. Shapiro, S.: Classical logic II: higher order logic. In: Goble, L. (ed.) The Blackwell Guide to Philosophical Logic, pp. 33–54. Blackwell (2001) 9. Rizaldi, A., Immler, F., Althoff, M.: A formally verified checker of the safe distance traffic rules for autonomous vehicles. In: Rayadurgam, S., Tkachuk, O. (eds.) NASA Formal Methods. NFM 2016, vol. 9690, pp 175–190. Springer, Cham (2016)

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10. Werling, M., Ziegler, J., Kammel, S., Thrun, S.: Optimal trajectory generation for dynamic street scenarios in a Frenét Frame. In: Proceedings of the 2010 IEEE International Conference on Robotics and Automation (ICRA 2010), Anchorage, Alaska, USA, pp. 987– 993 (2010) 11. Havelund, K., Rosu, G.: Efficient monitoring of safety properties. Int. J. Softw. Tools Technol. Transfer 6(2), 158–173 (2004) 12. Artho, C., Drusinsky, D., Goldberg, A., Havelund, K., Lowry, M.R., Pasareanu, C.S., Rosu, G., Visser, W.: Experiments with test case generation and runtime analysis. In: Börger, E., Gargantini, A., Riccobene, E. (eds.) Abstract State Machines. Lecture Notes in Computer Science, vol. 2589, pp 87–108. Springer, Heidelberg (2003) 13. Kuester, J.C.: Runtime verification on data-carrying traces. Ph.D. thesis, The Australian National University (2016) 14. Rosu, G., Havelund, K.: Rewriting-based techniques for runtime verification. Autom. Softw. Eng. 12(2), 151–197 (2005)

Evaluation of Sustainability of the Transport System of Urbanized Areas Considering the Development of Bicycle Transport Irina Makarova(&) , Vadim Mavrin , Kirill Magdin, Ksenia Shubenkova , and Aleksey Boyko Kazan Federal University, Syuyumbike pr-t, 10a, 423822 Naberezhnye Chelny, Russia [email protected], [email protected], [email protected], [email protected] Abstract. In the process of its development, humanity is constantly faced with environmental pollution. Despite the fact that the improvement of technology improves the quality of life of society, such rapid progress inevitably leads to a decrease in the state of the environment. As a result of economic, technical and technological development, the quality of human health is deteriorating. One of the most significant factors in environmental degradation is intensive automobilization. The article presents the main directions of reducing the negative impact of automobilization on the environment. It was noted that one of the promising trends in the desire for an environmentally friendly and safer level of development of the transport system is the active use of bicycle transport, which will improve the health of the population, reduce harmful emissions into the atmosphere, the noise level in the city, traffic congestion and solve the growing problem of the “first and last mile”. The article presents a simulation model of transport flows developed by the authors of one of the critical sections of the road network using the example of a large city. A computer experiment was made on the model and the emissions of pollutants and the noise level from vehicles were calculated for various flow parameters. It turned out that when replacing a part of motor transport by bicycle transport, the calculated reduction in emissions of CO, NOX, CXHY, SO2 and the equivalent sound level would be 20.0%, 20.7%, 8.9%, 14.1% and 9.1%, respectively. Keywords: Sustainability of transportation
Environmental safety
Cycling Air pollution




1 Introduction The increase in the level of automobilization in general contributes to the acceleration of the development of the production of goods and services, ensuring the speed and accuracy of delivery of goods and passengers, saving time, increasing the level of comfort of trips. However, there are negative factors associated with the development of the process of automobilization, which include environmental pollution, negative impact on the health, increased consumption of natural resources, alienation of territories and other factors. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 427–433, 2020. https://doi.org/10.1007/978-3-030-38666-5_45

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Currently, road transport is the largest source of emissions of pollutants. At the same time, the volume of emissions from vehicles, both relative in the structure of emissions and absolute, increases every year due to the growth in the number of vehicles and the volume of road transportation. In recent decades, the environmental performance of vehicles has improved significantly. However, this did not lead to a decrease in the emission of pollutants, as there is a continuous increase in the level of automobilization. So, in the world there are more than 1.2 billion cars [1]. According to the forecasts of the World Bank, the world car fleet will double up by 2050. Obviously, road transport will have an even greater impact on the environment. Creating a sustainable transport system is currently one of the main tasks. It is this direction of development that should be the goal of urban planning, taking into account the active growth of cities within the limits that allow the rational and safe use of the facilities of the road transport complex and the corresponding infrastructure. The purpose of this article is to develop a method to reduce the negative impact of the transport system of an urbanized area on the environment.

2 Materials and Methods The most common to date method of reducing the negative impact of the car on the environment is the use of hybrid cars. However, when using hybrid cars, the problem of battery disposal arises. In addition, hybrid cars are more complicated and more expensive than traditional cars. The use of electric vehicles is another area that has been intensively developing in recent years. However, non-renewable energy is also required to charge batteries. And the production of electric vehicles causes almost 4 times more damage to the environment than the production of traditional automobiles [2]. Since the beginning of the century, the production of biofuels has increased 10-fold. However, in recent years, growth has practically stopped, and in many countries (in particular, in the European Union) production has fallen [3]. Recent studies show that the operation of equipment, transportation, chemical processing of raw materials, disturbance of soil cover are inevitably accompanied by emissions of CO2 into the atmosphere. The final balance in some cases may be worse than when burning fossil fuels. Integral assessments of bio-energy technologies based on the life cycle show that emissions from biofuels are only 13% lower than emissions of conventional gasoline [4]. Hydrogen transport is a variety of vehicles that use hydrogen as a fuel. These can be vehicles with both internal combustion engines, gas turbine engines, and hydrogen fuel cells. The lack of hydrogen infrastructure, the danger of using hydrogen as a fuel due to its high volatility and ease of ignition and the high price of a car and its operation [5] hinders the development of hydrogen transport. In addition, hydrogen is produced by the consumption of a significant amount of electricity. Thus, a car with a reciprocating internal combustion engine based on hydrocarbon fuel from non-renewable fossil raw materials will remain the main one in the structure of vehicles fleet for a long time. One of the factors affecting the intensive growth of the car fleet is the lack of efficiency of public transport, as a result of which a significant part of people has to use

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individual transport. Its use, among other things, leads to a decrease in physical activity of urban residents, causing an increase in cardiovascular and other diseases. According to the Global status report on road safety 2018 [6], one of the promising trends in the desire for an environmentally friendly and safer level of development of the transport system is the active use of cycling. This will improve the health status of the population, reduce the level of harmful emissions into the atmosphere and reduce the noise level in the city, as well as reduce traffic congestion [7]. In addition, bicycle transport can be extremely effective in solving the growing problem of the “first and last mile”. Since the eighties of the twentieth century, the development of cycling as an integral part of the transport complex has become one of the priorities of the transport policy of most developed countries. The greatest progress was achieved by such countries as the Netherlands, Germany, Denmark, Sweden, France, Belgium and some others [8]. However, in Russia only recently began active research on this issue. According to studies, the most significant environmental aspects of operating vehicles are emissions and noise. We calculated the potential reduction in emissions and noise level using the example of one of the critical sections of the road network in Naberezhnye Chelny. The specificity of the city lies in the separation of industrial and residential areas. Regular public transport routes between these areas are not good developed due to unprofitability. Therefore, most workers prefer to use individual transport. In this regard, there are significant difficulties in delivering the population to the main employer of the city of PC KAMAZ: despite the availability of alternative routes, congestion and traffic jams are observed (Fig. 1).

Fig. 1. The investigated section of the road network.

In Fig. 1, areas with high traffic density and low speed are shown in red, areas with medium density and speed are shown in yellow, and low density and high speed are shown in green. Traffic data was obtained through field surveys of traffic flows.

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In order to investigate the potential for reducing the negative impact of this area on the environment, routes were proposed on which it is possible to use bicycle transport provided the bicycle infrastructure is created (Fig. 2).

Fig. 2. The investigated routes of the road network.

We have constructed a simulation model of these transport routes in a software based on a discrete-event approach using a traffic library (Fig. 3). The results of field surveys were used as initial data on traffic intensity at the section (Fig. 4). Performing a computer experiment on the model showed that with the existing traffic flow parameters, sections of routes with high traffic flow intensity are observed, which is consistent with the results of field surveys. We conducted a survey of participants in the movement of this route. The environment for the implementation of the questionnaire was selected online service “Google Docs”, which has simple tools for the preparation of the questionnaire with a clearly aligned logic and allows you to get a structured result. After processing the data, it turned out that about 2% of the participants in this route use bicycle transport. 24% of respondents are ready to use the bike instead of individual cars and public transport while improving bicycle infrastructure (bicycle lanes, safe crossings at the intersection with roads, rest and repair areas, self-service station, guarded indoor parking, rental stations at affordable prices).

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Fig. 3. Simulation model of routes with current traffic flow parameters.

Fig. 4. The intensity of car traffic depending on time.

According to a computer experiment on a model with predictive parameters reflecting a decrease in the number of motorists in favor of an increase in the number of cyclists, a decrease in the intensity of traffic is observed (Fig. 3 is marked in red), which will reduce the negative impact of traffic on the environment (Fig. 5).

Fig. 5. Simulation model of routes using cycling.

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Reducing of the total emission of pollutants, M, g/km, is calculated by the formula (1), developed by the authors [9]. M¼

n1  m1  n  m   X  X  X  X MPl 1 þ MPl 2 þ MLl 3 þ MLl 4 þ MPl 3 þ MPl 4 þ MLl 1 þ MLl 2 ; l¼1

l¼1

l¼1

l¼1

ð1Þ  n  P MPl 1 þ MPl 2 – emissions of pollutants into the atmosphere by cars that are in l¼1  m  P MPl 3 þ MPl 4 – emissions of line at the intersection in the direction of movement; where

l¼1

pollutants into the atmosphere by cars queuing in front of the intersection in the opposite  n1  P MLl 3 þ MLl 4 – emissions of pollutants into the atmosphere by cars direction; l¼1  m1  P moving along this road in the direction of movement; MLl 1 þ MLl 2 – emissions of l¼1

pollutants into the atmosphere by cars moving on this road in the opposite direction.

3 Results and Discussion According to our calculations, an increase in the number of cyclists and a decrease in the number of cars on a total of two routes will result in a reduction in CO emissions to 20.41 t/year, NOX to 1.57 t/year, hydrocarbons to 2.87 t/year, SO2 to 0.85 t/year, as well as increase the average speed of the traffic flow (Fig. 6).

Fig. 6. Average duration of travel at different speeds (a); volumes of pollutant emissions and equivalent sound level (b).

The reduction in traffic noise is calculated by the formula (2) [10]: L ¼ 9:5
lgðN0  N1 Þ þ 12:64
lgðv  v1 Þ þ 7:98
lgð1 þ PT Þ þ 11:39;

ð2Þ

where N0 – estimated base traffic, car/h; N1 – estimated traffic intensity after changes in traffic parameters, cars/h; v – speed, km/h; v1 – speed of movement after changes in traffic parameters, km/h; PT – share of trucks and buses, %.

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According to our calculations, the equivalent noise level will drop from 80.3 dBA to 73 dBA.

4 Conclusion Thus, the development of bicycle infrastructure would expand the number of potential users of bicycle transport from 2% to 24% of total number of movement participants on this route, that will result in a reduction in CO emissions by 20.0%, NOX by 20.7%, hydrocarbons by 8.9%, SO2 by 14.1%, the equivalent sound level by 9.1%. Currently, the model does not take into account such factors as seasonality and weather conditions. To add these factors to the model, it is necessary to conduct an additional survey of a sufficient number of potential users of bicycle transport, so that it is possible to determine the dependence of the use of bicycle transport on these factors. This study will be carried out in the following papers.

References 1. Arena, F., Ticali, D.: The development of autonomous driving vehicles in tomorrow’s smart cities mobility. In: Simos, T.E., Kalogiratou, Z., Monovasilis, T., Simos, T.E. (eds.) AIP Conference Proceedings, vol. 2040, no. 1. American Institute of Physics Inc., USA (2018) https://doi.org/10.1063/1.5079196. Accessed 27 Mar 2019 2. Gelmanova, Z.S., Zhabalova, G.G., Sivyakova, G.A., et al.: Electric cars. Advantages and disadvantages. In: Journal of Physics: Conference Series, vol. 1015, no. 5. IOP Publishing Ltd., Russia (2018). https://iopscience.iop.org/article/10.1088/1742-6596/1015/5/pdf. Accessed 27 Mar 2019 3. Renewables 2016. Global Status Report, REN21 Steering Committee. http://www.ren21.net/ wp-content/uploads/2016/05/GSR_2016_Full_Report_lowres.pdf. Accessed 17 Jan 2019 4. Qian, G.: Scientometrics analysis on the intellectual structure of the research field of bioenergy. J. Biobased Mater. Bioenergy 7(2), 305–308 (2013) 5. Gis, W., Schaap, G.: Hydrogenation of road transport on the example of Sweden and Poland. In: Mitianiec, W. (ed.) IOP Conference Series: Materials Science and Engineering, vol. 421, no. 4, Institute of Physics Publishing, Poland (2018). https://www.researchgate.net/ publication/328238179_Hydrogenation_of_road_transport_on_the_example_of_Sweden_ and_Poland. Accessed 27 Mar 2019 6. WHO: Global Status Report on Road Safety 2018. World Health Organization, Geneva (2018) 7. Makarova, I., Shubenkova, K., Pashkevich, A., Boyko, A.: Smart-bike as one of the ways to ensure sustainable mobility in smart cities. In: Bilas, V., Magno, M., Ferrero, F. (eds.) 7th International Conference on Sensor Systems and Software, pp. 187–198. Springer Verlag, Germany (2017) 8. Si, H., Shi, J.-G., Wu, G., Chen, J., Zhao, X.: Mapping the bike sharing research published from 2010 to 2018: a scientometric review. J. Cleaner Prod. 213, 415–427 (2019) 9. Makarova, I., Khabibullin, R., Mavrin, V., et al.: Simulation modeling in improving pedestrians’ safety at non-signalized crosswalks. Transp. Probl. 11(4), 139–150 (2016) 10. Galyshev, A.B.: Ensuring environmental and road safety of the motor transportation complex due to the development of cycling. Ph.D. thesis. MADI, Moscow (2017)

Planning Method for the Maintenance and Repair of the Vehicle Fleet Based on the Life Cycle Contract Irina Makarova1(&) , Eduard Mukhametdinov1 , Larisa Gabsalikhova1 , Anton Pashkevich2 , and Ilsur Giniyatullin1 1

Kazan Federal University, 423822 Naberezhnye Chelny, Russia [email protected] 2 Tallinn University of Technology, 19086 Tallinn, Estonia [email protected]

Abstract. Solving the problem to improve the motor vehicles reliability is provided by the automotive industry, on the one hand, through the production of more reliable vehicles and their components and, on the other hand, by improving the methods of vehicles’ technical operation. Reliability indicators arise themselves in the vehicle’s operation process and depend on methods and conditions of its operation, accepted system and methods of maintenance and repair (M&R), operating modes, etc. Authors describe a long-term planning method of vehicles’ M&R when concluding the life cycle contract. Data sources for such long-term planning of M&R were identified. It is proposed to use the extrapolation method based on current values of technical condition indicators for future periods, taking into account conditions and product operation modes. Constructor and manufacturer get an opportunity to analyze statistics on vehicles’ faults and failures for organizational, design or technological decisionmaking. Proposed method helps to improve the vehicle fleet’s technical state and to manage its operation. Keywords: Maintenance and repair


Life cycle contract
Vehicle fleet

1 Introduction With the transition to Industry 4.0, the efficiency of the system to maintain vehicles in good operating condition starts to be more and more important. At the same time, there is a certain complexity to organize such a system, because the concept of Industry 4.0 implies the manufacture of a product for an individual customer according to its specific demands, which increases an amount of product modifications. Classical approaches when the vehicles manufacturer is responsible for the entire life cycle of a product are often not enough effective due to the fact that an owner does not take responsibility for the technical state of vehicle and, thus, can break the operating conditions as well as maintenance regulations. From year to year products of automobile factories becomes more complicated both technically and programmatically, © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 434–444, 2020. https://doi.org/10.1007/978-3-030-38666-5_46

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requires the thorough preparation at manufacturing site and in service network. Furthermore, manufacturer will be interested to create a corporate service network, which should allow to realize the principle of the responsibility for an own product during the whole life cycle [1]. That is particularly relevant for modern lorries, because in comparison to passenger cars it is practically impossible to maintain such vehicles in small vehicle repair shops. Also thanks to an own service system the full information about the operation specifications as well as maintain and repair of both a particular truck and the whole vehicle fleet is collected (Fig. 1).

Fig. 1. Unified information environment to support a vehicle’s life cycle.

One of the tools to organize an interaction between manufacturer and vehicle’s owner can be a life cycle contract (LCC), which considered as an option of publicprivate partnership (PPP). It is a long-term agreement, under which the contractor undertakes to carry out the purchase of product and maintenance of purchase object, and the state pays for it. As a rule, such cases are related to infrastructure facilities, namely, to roads, bridges, tunnels, etc., but also such regulations are applied when purchasing vehicles for public use (subway cars, buses, etc.) or air, sea and river vessels. In our opinion, a similar partnership option can also be used for an interaction between owners of large logistics companies and vehicle manufacturer. In this situation, the contract will be concluded between two parties: owner, who buys a vehicle, and manufacturer, whose responsibilities include to keep a vehicle in a technically sound condition during its life cycle. LCC will allow to transfer the part of risks to the owner, who will be interested to implement the operating regulations and standards in order to reduce the probability of some risks.

2 Current Status of the Problem LCC in the world practice has proven itself as a good solution in different industries types. In the Russia, a successful example of LCC is the operation of railway trains. This allows the owner to concentrate only on the monitoring of object operation parameters and on the control of specified target indicators. Thus, article authors [2] presented a life cycle model to estimate the life cycle cost of rail vehicle. The proposed model is focused on the calculation of service strategies. The scheme of LCC is widely used in the field of

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transport infrastructure. LCC is often realized within the scope of PPP. The development issues of PPP are analyzed in articles [2–4]. The author of the research paper [3] considers the strengths and weaknesses of PPP as well as its development prospects. In the article [4] author concludes that partnership relations could not be the most appropriate means for some types of public goods and services. Therefore, they should be applied mainly to those social problems, which require special advantages of partnership. In the article [5] the importance of interaction between partners was emphasized, without which public and private parties cannot come to a common understanding, cannot contribute to enrich the project content as well as cannot develop mutual trust. The research work [6] provides rationale reasons to attract the participation of private business in developing countries. The author identifies critical success factors and policy requirements for the successful implementation of PPP. The research results presented in the article [7] can serve as an information source on the private sector’s motivation formation to participate in PPP. The article [8] analyses a role of PPP in the transport management by using the example of car sharing. Authors of the research [9] consider pricing issues based on marginal social cost and analyse disadvantages and advantages of different PPP options. In the book [10] it is indicated that although the PPP was used to provide transport projects and services, but studies on this issue have a fragmentary nature. PPPs are complex mechanisms, which require an interdisciplinary approach to ensure their success. The article [11] analyses the success and failure factors of three large PPP projects in the transport field, namely: the concession project of toll road in Lekki (Nigeria), the toll road N4 (South Africa/Mozambique) and the port of Maputo (Mozambique). The aim of this study was to develop policy measures for the future effective implementation. The information set out in the article [12] shows that the use of a LCC model in the framework of supply and maintenance contracts for public transport fleet allows to provide the city with vehicle of new generation with increased comfort and safety, to obtain additional reliability guarantees and travel schedule adherence, to keep consumer performance of vehicle during the whole operation period. The project success will depend on how well the risks are understood and to what extent the problem of sharing responsibility for them is solved. The works [13–15] considered the nature of risk transfer in PPP, since it is associated with large financial resources and long contract duration. The article [16] defines management approaches, which help or hinder the harmonization of private sector participation in urban infrastructure projects to increase the urban environment sustainability. The possibility to implement LCC in the automotive industry, when planning of motor vehicles’ M&R, should be studied based on the experience in other areas: in rail transportation, in road construction and other infrastructure projects.

3 Hypotheses and Methods 3.1

Risk Classification

The operation stage includes two components: commercial operation (the transportation processes realization) and technical operation (operating capacity maintenance). These two directions are inextricably linked: commercial operation is provided by

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high-quality technical operation. In the LCC context, this approach shares risk management responsibility between owner, which is responsible for commercial operation, and manufacturer, which will be responsible for technical operation. Thus, each of the parties controls the respective risks types (Fig. 2). At the same time, it is necessary to take into account the possible risks associated with functioning the vehicle service system. The reason is so that manufacturer invests funds to create such a system and main goal is to reach its optimal functioning mode. On the other hand, the vehicle’s branded service system is characterized by unsteady demand. Therefore, parameters of technological process are stochastic, which causes additional risks generated by the unsteadiness of demand, and results unbalanced load equipment and personnel loading [17–19].

Fig. 2. Risk classification in the automotive industry.

It is important to understand that all risks types are related in a varying degree to each other and the appearance of one risk type can have a negative impact on the work of all subsystems associated with it. Technical risks can be defined as probability of loss due to: (1) negative research results; (2) failure to achieve the planned technical parameters during design and technological development; (3) low production technological capabilities, which does not allow to apply the results of new developments; (4) side effects or delayed problems when using new technologies and products; (5) failures and equipment breakdown, etc. Technical risk is attributed to the group of internal risks, because these risks can be directly influenced by enterprise as well as their occurrence, as a rule, depends on the production activity of enterprise. 3.2

Hypotheses and Approaches in the Development of Methods

The long-term planning methods of vehicles’ M&R is necessary to make possible to form a plan-schedule of vehicles’ M&R for the specified period. It gives an opportunity to predict and to estimate the possible volumes of work associated with types of services based on the predicted technical condition of fleet and possible risks. From the methodological point of view, the long-term planning for the vehicles’ M&R is similar to the prediction of vehicles’ technical condition. That is why the list of data sources is in many ways similar: (1) long-term fleet operation plans to determine the fleet’s type and age structure as well as to cluster it into groups, taking into account future expansion and renewal; (2) current values of indicators concerning operating time of vehicles’ samples and their component parts; (3) resource associated with operating time till a certain technical impact; (4) planned operating time for a certain period,

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established by the vehicles manufacturer based on the reference operation group; (5) coefficient presenting the intensity of the operating time when used in other of operation groups; (6) seasonal factors affecting the operation intensity; (7) probability to provide unplanned technical impacts on vehicles; (8) data from on-board diagnostic systems (if available). The current values of operating time for vehicles and their components will be entered into the system, providing information support for M&R processes. Data input will be done by using specialized tools either manually, taking into account the readings from the on-board diagnostic systems, or automatically, on the basis of integration with the objective control system. Planned operating time for a certain period is determined by the vehicles manufacturer based on the statistical data for each reference operation group and is indicated in the corresponding design and technological documentation. The coefficients presenting the growth intensity of operating time when using vehicles of other operation groups, seasonal coefficients as well as probability values of the unplanned technical impacts implementation are normativereference information with an economic nature. The legal framework and regulations to conduct these data sources must be developed and approved by contractor and customer, who sign agreement to support the vehicles life cycle maintenance, in accordance with the state laws.

4 Results and Discussion 4.1

Method for the Long-Term Planning of Motor Vehicles’ M&R

To carry out the long-term planning of motor vehicles’ M&R, it is proposed to use the method to extrapolate current values of the technical condition indicators for future periods, taking into account influential factors, such as conditions and modes of vehicle operation. To improve the efficiency of such planning, it is necessary to remember that different units, components and systems of a motor vehicle have different resources and different degrees of reliability, which depend usually on many factors with stochastic nature. The prediction of failures allows to predetermine possible problems and to make the well-timed replacement of unreliable elements. A failure of motor vehicle occurs at the point of time T, which can be predicted with a certain probability. As the performance analysis shows, the failure rate of vehicle k(t) is divided into three operational phases: (1) the first phase is connected with a decrease of failure rate and known as early failures; (2) the second stage is characterized by a constant failure rate, known as random failures; (3) the third phase, also known as wear-out failures, is an increase of failure rate. During the period of running-in, an enhanced intensity of failures is observed. It is connected directly with the process of components running-in and caused usually by manufacturing defects. During the regular operation, failures have a random nature and appear unexpectedly. In the first instance, it is connected with the noncompliance with operating conditions, load changes, impacts of negative external factors, etc. The third period is characterized by a failure rate increase, which is caused by aging and other reasons related to long-term operation. Depending on the mileage from when the vehicle’s operation starts, not only

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the number of failures goes up, but also both the labor costs to eliminate them and the costs associated with keeping vehicles in working condition increase. At the same time, there is a decrease in the technical availability as well as annual runs and performance of vehicles are reduced. The long-term forecasts should be carried out taking into account the type and age structure of vehicle fleet as well as statistical information about failures. Therefore, service and spare parts planning mechanisms will vary. For parts, units, components and their elements there are three main types of failure reasons, which are corresponding to a specific period of operation: (1) latent manufacturing defects; (2) overload, external effects; (3) wear, aging, consumption. The long-term planning method on M&R of vehicles as well as their components can be divided into stages corresponding to the reliability curve. For the initial stage of vehicle operation, it is necessary to create a reserve of spare parts. Such reserve should include components, which are most susceptible to failures during the running-in period. In this regard the automotive company establishes a warranty period. For the second stage (regular operation), failures depend strongly on the operating conditions, they have a stochastic nature and, therefore, the forecast of the demand for spare parts is based on the dependencies established by using the analyze of statistical information. At the third stage, the service strategy is realized taking into account the type and age structure of vehicle fleet as well as reliability indicators. This strategy must consider the resource for a specific group of vehicles operated in specific conditions. It is necessary to pay attention on the expediency to continue a vehicle operation keeping in mind the cost of its repairs (both the labour intensity and the cost of spare parts). The most effective method to increase the vehicles operational reliability is the prediction of its technical state, i.e. failures for a certain time as well as their prevention through planning service time, spare parts supply according to the required specification and quantity taking into account operating conditions, climatic conditions in a particular region; year time; type, model and vehicle configuration. The failure rate indicator is used in the problems of vehicle failure prediction. This indicator is connected with the reliability function P(T) by the following formula: kðtÞ ¼ P0 ðtÞ=PðtÞ:

ð1Þ

^

The statistical estimate kðtÞ for failure rates can be calculated in the following way: ^

kðtÞ ¼

nðt þ Dt=2Þ  nðt  Dt=2Þ : ½N  nðtÞDt

ð2Þ

The time interval Dt is chosen so that it contains a sufficient number of values tk and is sufficiently small in comparison with the total duration of tests or observations. To meet these conflicting requirements, it is necessary to have large-scale samples. If the end of a running-in is taken as the start of objects operation and the limit state is the point of time when the period of regular operation ends, then during the operation time,

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it can be considered k = const, which corresponds to the direct part of the reliability curve. The following formula is got as a result: PðtÞ ¼ exp½kt:

ð3Þ

The mathematical expectation of the service life (resource) is equal to 1=k, so the formula can be written as: PðtÞ ¼ expðt=tc Þ;

ð4Þ

where tc = E[T] – mathematical expectation of the service life. An example of the operation process will be considered: vehicle unit is operated before failure, then it replaces with new one from the same reserve lot, then the replaced unit is being brought to failure and is changed by the third one, and so on. It is assumed that the length of time to replace one object with another one is small compared to the duration between consecutive failures. The process is described by using the sequence of t1, t2, … moments of failure. Since a time between failures is a random value, this sequence is a stream of random events. Addition to the unit of the time distribution function between neighboring events coincides with the probability of failure-free operation P(t). If this probability does not depend on the number of events in the stream, it means that this stream is stationary, recurrent, and Markov one. If the reliability function P(t) has the form (3), then the stream of random events is Poisson one. The probability of occurrence to failure k on the interval [0, t] follows the Poisson law: Qk ðtÞ ¼

ðktÞk exp½1  kt; k!

ð5Þ

where k = (0, 1, …). Having a data on residual resources tres calculated on the basis of the probability of failures P(t), it is possible to determine the probable failure date for any unit: Tfailure ¼ Tb þ tres

ð6Þ

where Tb – date when starting the prevention of the predicted failure. The long-term planning method of M&R, which is proposed to implement in the system, suggests few options: more rigorous approach to planning, when technical impacts on a vehicle and its component parts are planned within certain periods, but has an advisory nature, or softer approach, when technical impacts on vehicle and its components are planned only if it is necessary, i.e. work on the technical condition is carried out. The current value of operating time indicator (amount of km run) is transmitted from the vehicle’s on-board system or its remote control system. This value is calculated as follows: B0ijk ¼ Rik  DAij  Cj ;

if Aij ¼ 0;

ð7Þ

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or: B0ijk ¼ Bijk  DAij  Cj ;

if Aij 6¼ 0:

ð8Þ

where: B0ijk – current value of the operating time indicator i by item j, remaining (without taking into account correction coefficients) until a certain type of regulatory technical impacts k; Rik – manufacturer’s regulated value of the operating time indicator i for a certain type of regulatory technical impacts k; DAij ¼ A0ij  Aij – difference between current and previous values of the operating time indicator i by item j; A0ij – current (actual) value of the operating time indicator i by item j; Aij – previous value of operating time indicator i by item j; Cj – cumulative correction coefficient by item j, showing the intensity of operation; Bijk – calculated value of the operating time indicator i by item j, till a certain type of regulatory technical impacts k. Calculation of the predicted value of the operating time indicator i by item j until a certain type of regulatory technical impacts k during the planned period l: Dijkl ¼ B0ijk  Pijl  Cj :

ð9Þ

The obtained value Dijkl is analyzed if Dijkl  Fijk ;

ð10Þ

where Pijl – planned increase in the operating time indicator i by item j in period l; Fijk – threshold value of the operating time indicator i by item j for a certain type of regulatory technical impacts k. The threshold value of the operating time shows the allowable service interval, which is set by the manufacturer in the service book. For example, for KAMAZ vehicles of environmental level EURO-2 for TO-15000 (by km run) this value is 15,000 km, i.e., it is allowed to perform maintenance in the interval from 13,500 to 16,500 km. As a result, the following will be determined: period l, for which maintenance is planned; forecast indicator of operating time in a certain period Dijkl . Dijkl þ 1 ¼ Dijkl  Pijl þ 1  Cj :

ð11Þ

Proposed method works separately and simultaneously: for each sample of vehicle or its component; for each operating time indicator; for each group of types of technical impacts (i.e., if the conduction of one impact excludes another one, it becomes possible only after reaching the next milestone of operating time). 4.2

Exemplary Calculation of Warranty Costs

To guarantee risk’s operational assessment, the functional dependence of the risk value on the warranty time and the amount of deductions to the guarantee fund of the enterprise in % of the vehicle value are determined. Data on faults of KAMAZ vehicles operated in 28 countries are used. Since in each country vehicles are purchased in lots

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for a certain type of work (construction, agriculture, utilities, etc.), and the organization and quality of services are homogeneous throughout the country as a whole, these values were used as the warranty service’s cost. 2 P ¼ 7;4
1012
t2 þ 0;76
C%  4;6
107
C%
t  1;78
C% þ 3;8
107
t þ 1;

ð12Þ where t – operating time indicator, km; C% – deductions to the enterprise’s guarantee fund. The analysis of statistical data in the STATICTICA package allowed to identify units and components of motor vehicles, which have the largest number of failures (Table 1). The relative number of failures is presented in Table 2. To determine the cost of replacing a part, its price was taken into account, the complexity of eliminating the failure and the mileage, at which the failure occurred (Table 3). The electrical equipment system was chosen as the object of study (Figs. 3 and 4).

Table 1. Statistics of the most common failures. Units and components of vehicles

*Absolute RUN, 1,000 km value 0–10 10–20 20–30 **Reduced Number of failures value

30–40

40–50

50–60

60–70

70–85

Engine

* ** * ** * **

132 0.22 90 0.31 116 0.22

115 0.17 58 0.18 102 0.21

112 0.16 42 0.15 95 0.20

86 0.15 37 0.14 83 0.17

75 0.10 21 0.13 57 0.14

52 0.20 19 0.12 38 0.13

26 0.09 14 0.10 24 0.10

22 0.07 9 0.07 15 0.06

* **

52 0.27

34 0.20

29 0.19

25 0.17

19 0.14

15 0.13

12 0.12

9 0.07

Transmission Electrical equipment and appliances Engine clutch

Table 2. The relative number of failures by units and components in 2014. Name of unit/component Electrical equipment Engine Transmission Engine clutch

Total number of failures 530 610 290 195

% failures on sold vehicles number 35.3 40.6 19.3 13

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Table 3. Distribution of costs and labour intensity referring to the run of the electrical system. Run, km 0–1,500 1,500–2,500 2,500–5,500 5,500–9,500 9,500–12,500 12,500–14,500 14,500–20,500 20,500–26,500 26,500–35,500 35,500–48,000 48,000–68,000 68,000–72,500 72,500–75,500 80,000

Costs of spare parts, % Labour intensity to eliminate a fault, % 42.2 37.7 39.3 35 35 24.6 27 21.1 24.7 19 17 17 19 15.9 15.9 14.3 14.1 12.8 12.5 11.6 11 10.7 9.8 10.5 6.5 9.6 3.2 5.4

Fig. 3. Distribution frequency of the cost of warranty repairs with an operating time indicator of 70 thousand km.

Fig. 4. Surface costs for replacing faulty electrical equipment during the break-in period.

5 Conclusion The proposed method of long-term planning of M&R will prevent the failures occurrence in the period before the scheduled maintenance. According to the developed methodology, the maintenance is shifted to the failure limit. Each of the service process participants will promptly receive the required information. The operating organization will be able to assess condition and resource of each vehicle, the service center will have access to the repair documentation during M&R, the manufacturer will be able to collect repair statistics, to make an organizational, design or technological solution, namely: a design change, or claims to the supplier of the purchased component. This mechanism makes possible to identify the factors contributing to a decrease in the value of the technical readiness coefficient as well as to influence on these factors with the aim to achieve an increase in the coefficient to the required level.

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References 1. Industry 4.0. http://www.up-pro.ru/library/opinion/industriya-4.0.html 2. Jun, H.K., Kim, J.H.: Life cycle cost modeling for railway vehicle. In: International Conference on Electrical Machines and Systems (ICEMS), Seoul, pp. 1989–1994 (2007) 3. Bovaird, T.: Public-private partnerships: from contested concepts to prevalent practice. Int. Rev. Adm. Sci. 70(2), 199–215 (2004) 4. Brinkerhoff, D.W., Brinkerhoff, J.M.: Public-private partnerships: perspectives on purposes, publicness, and good governance. Public-Private Partnerships: Familiar Ground Fresh Perspect. 31(1), 2–14 (2011) 5. Koppenjan, J.J.F.M.: The formation of public-private partnerships: lessons from nine transport infrastructure projects in the Netherlands. Public Adm. 83(1), 135–157 (2005) 6. Jamali, D.: Success and failure mechanisms of public private partnerships in developing countries: insights from the Lebanese context. Int. J. Pub. Sec. Man. 17(5), 414–430 (2004) 7. Ye, X., et al.: Empirical analysis of firms’ willingness to participate in infrastructure PPP Projects. J. Constr. Eng. Manag. 144(1) (2018) 8. Dowling, R., Kent, J.: Practice and public-private partnerships in sustainable transport governance: the case of car sharing in Sydney, Australia. Transp. Pol. 40, 58–64 (2015) 9. Evenhuis, E., Vickerman, R.: Transport pricing and public-private partnerships in theory: issues and suggestions. Res. Transp. Econ. 30, 6–14 (2010) 10. Verweij, S.: Public private partnerships in transport: trends and theory. Transp. Rev. 37(5), 685–687 (2017) 11. Osei-Kyei, R., Chan, A.P.C.: Developing transport infrastructure in Sub-Saharan Africa through public-private partnerships: policy practice and implications. Transp. Rev. 36(2), 170–186 (2016) 12. Turgeneva, V.V., Sekerin, V.D.: “Life cycle contract” in the field of transport infrastructure the new public-private partnership mechanism. MIR [World] 8(4)(32), 536–543 (2017) 13. Hodge, G.A.: The risky business of public-private partnerships. Aust. J. Public Adm. 63(4), 37–49 (2004) 14. Shen, L.Y., Platten, A., Dengc, X.P.: Role of public private partnerships to manage risks in public sector projects in Hong Kong. Int. J. Project Manag. 24(7), 587–594 (2006) 15. Medda, F.: A game theory approach for the allocation of risks in transport public private partnerships. Int. J. Project Manag. 25(3), 213–218 (2007) 16. Koppenjan, F.M., Enserink, B.: PPP in urban infrastructures: reconciling private sector participation and sustainability. Pub. Adm. Rev. 69(2), 284–296 (2009) 17. Makarova, I., et al.: Improving the logistical processes in corporate service system. Transp. Probl. 11(1), 5–18 (2016) 18. Buyvol, P., et al.: Improving the branded service network efficiency based on its functioning evaluation. Astra Salvensis 2(2017), 373–385 (2017) 19. Makarova, I., et al.: System approach at risk management of the autoservice enterprise. Transp. Probl. 8(4), 5–16 (2013)

Simplified Mathematical Model of Changes in Sound Power Level Caused by the Perpendicular Forces that Arise When the Rail Contacts the Wheel with Flat Viačeslav Petrenko(&) and Vladas Kukėnas Vilnius Gediminas Technical University, J. Basanavičiaus 28, 03224 Vilnius, Lithuania {viaceslav.petrenko,vladas.kukenas}@vgtu.lt Abstract. The work reviews the problems that arise when the wheel with flat contacts the rail, the detection and diagnostic methods of the latter. Since all wheel with flat detection methods are very complex and lack precision it was intended to create a simplified mathematical model of changes in sound power level caused by the perpendicular forces that arise when the rail contacts the wheel with flat, theoretic calculations were performed. It was determined that in theory sound power level changes can be utilized to detect and determine such defects. Preliminary values of the diagnostic parameters were calculated, their definition model was presented. Keywords: Railway vehicle


Wheels with flat
Sound power level

1 Introduction The safety, stability, noise and comfort levels of the railway traffic depend on the interaction of the wheel and the rail. Solutions to the problems caused by the rail and track interactions with increase of load and speed are becoming more relevant. The forces that arise during the contact of wheel and rail influence the dynamic processes of rolling stock and track. The amount of force is directly determined by the speed of movement of the rolling stock, physical and mechanical properties of the wheel and rail, geometric parameters of defects. Geometric deviations of the wheel surface cause dynamic shifting, punches, vibrations and noise while rolling. However the main issue from the railway safety perspective is the rolling stability. Forces that arise due to the wheel defects and rail and wheel contact may cause the wheel to lose contact with the rail thus leading to derailment, accidents or serious incidents. Wheel defects are rarely detected in the initial stages of usage and they increase with time. When the defected wheel rolls on the rail, forces interacting at their touching point increase. They may increase timefolds. Analysis of the origin of such forces determined that in case of certain loads the magnitude of the forces depends on the wagon rolling speed, defect depth and inclination angle. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 445–454, 2020. https://doi.org/10.1007/978-3-030-38666-5_47

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There are many dynamic rail and wheel interaction models for determining such forces, their examples are given in [1–4]. There are many and different mathematical models for wheel with flats. They are reviewed in works [1–4]. All of them state that vertical dynamic forces caused by wheel or rail defect may create dynamic forces that are 3–4 times higher than the load of the defect free wheel. Monitoring and usage limitations of the rolling stock with surface defects increases the resistance of the main constructional elements of rolling stock and track to the momentary impacts and fatigue. Many countries create and use the automated wheel with flat detection systems that use different methods to detect the increased wheel load on rail. Some systems, e.g. ATLAS-LG, WIM-WIM, WILD, AGUILA (Spain) directly measure the impact forces, other systems use the derived parameters of the changes of such forces – LASCA deviations. Presently the sound caused by the forces that arise from the interaction of wheel and rail are being increasingly researched and the results are applied in the wheel defect diagnostics [5]. Changes of the sound power level depend on the changes in the forces caused by the rail and wheel interaction, therefore the purpose of this work is to create the simplified calculation model for the created forces, compare its results with the results of field experiments and create a theoretic model to determine the sound power level changes.

2 Modeling the Dynamics of Train To determine wheel and rail contact forces, the computer model of the experiment was created. For this purpose, the Universal Mechanism (UM) program package was used. It was created for simulation of kinematics and dynamics of mechanical systems. Also, that software allows to simulate of dynamics of fully parameterized railway vehicles (locomotives and wagons). The simulation is performed in time domain by means of numeric integration of differential or differential-algebraic equations of motion [6]. The computer model of a typical 4-axle freight wagon with 2-axle bogies was created using the UM software package (Fig. 1). The model allows researchers to investigate the basic dynamic characteristics of the wagon when wagon moving in straight, curved track and switches taking into account deterministic and random railway track irregularities. Technical parameters of the wagon model (wheels profile, suspension and etc.) correspond to the standard operational and repair requirements. To simulate the conditions of the experiment on the first wheel set 2.0 mm flat defect L3 was created. The initial length L1 of the flat is 87.0 mm, the decrease of the deformed part length L2 due to steel plastic deformation is 37.4 mm and cubic parabola used for smoothing the flat ends (Fig. 2). For research aims, the Massless rail track model was used. Massless track model treats rail (and other track parts) as a massless force element. Track model was specified by vertical and lateral stiffness, torsional stiffness, vertical and lateral damping. Stiffness and damping parameters recreates the necessary conditions for stabilized railway

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track with concrete sleepers, braked stones ballast and summer time conditions. Railway track irregularities were generated according to experts of International Union of Railways spectral power density function for good track quality.

Fig. 1. Model of four-axle wagon and wheel/rail profiles.

Fig. 2. Definition of flat parameters.

Computer simulation allows to define a large number of parameters, in our case for calculations of Sound power level it is necessary to determine wheel-rail contact normal forces. For one-point contact and two-point contact only wheel profile tread and rail head normal forces N were identified (Fig. 3).

Fig. 3. Normal forces acting on wheels.

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3 Computer Simulation Results UM Experiments module was used to determine wheel-rail normal forces of freight wagon for different experiment conditions. In a series on numerical experiments the wagon speed changed in steps: 8.3; 11.1; 13.9; 16.7; 19.4 and 22.2 m/s. Also experiments were carried out for empty (24,000 kg) and fully loaded (84,500 kg) freight wagons. Simulation for 8.3 km/h speed and for empty and loaded wagon shown in Figs. 4 and 5. Obviously, the wheel with flat created strike loads. For empty wagons maximal normal forces did not exceed 194 kN and for fully loaded wagons the maximal normal forces reaches 256 kN. Experiments carried out for all speed steps and for example for 22.2 m/s speed empty wagons maximal normal forces is 262 kN and for loaded – 473 kN (Figs. 6 and 7).

Fig. 4. Normal forces acting on first (green line) and second (violet line) left empty wagon wheels at 8.3 m/s speed.

Fig. 5. Normal forces acting on first (green line) and second (violet line) left loaded wagon wheels at 8.3 m/s speed.

Analysing and filtering received data for all wheel sets, speed steps and wagon load, dependence between a maximal normal forces for all speed steps is formed (Fig. 8). The graph shows the increase of maximal normal forces for loaded and empty wagons left and right wheels (with flat) with the speed increase.

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Fig. 6. Normal forces acting on first (green line) and second (violet line) left empty wagon wheels at 22.2 m/s speed.

Fig. 7. Normal forces acting on first (green line) and second (violet line) left loaded wagon wheels at 22.2 m/s speed.

Fig. 8. Maximal normal forces acting on first loaded wagon left and right wheels (grey and blue lines) and empty wagon left and right wheels (green and red lines) with flat for 8.3–22.2 m/s speed diapason.

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Fig. 9. Testing site with measuring equipment and freight wagon wheel with flat [4].

Fig. 10. Examples of the vertical forces for empty and loaded wagons for wheels with flat [7].

500 Maximal normal forces, kN

400

Computer simulaƟon results Experemental data for A-B direcƟon

300 200

Experemental data for B-A direcƟon

100 0 0

5

10

15

20

25

Speed, m/s

Fig. 11. Comparison of simulation results and field measurements for loaded wagon and 2 mm wheel flat (summer conditions).

Received results were compared with real field tests results. In these field tests, forces between damaged wagon wheels and rails were determined (Fig. 9). Tests were carried out for different whether conditions (summer and winter time), different wheel defects, different speed, different wagon load and etc. Field tests results, identical for

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computer simulation conditions shown on the Fig. 10. Because the measurements of the normal forces was made on the 4-meter long railway track, only one strike is shown on the graph. Collecting, processing and analysing the data obtained from field tests and computer simulation we can compare the results (Fig. 11). Field tests maximal normal forces have difference depending on measurement direction or direction of train movement. From Joniskis station (A-B direction) level of the forces is bigger than in the opposite direction to Joniskis station (B-A direction). This can be explained by the errors in measurements and changes in the experimental conditions. Till 15 m/s computer simulations results curve is located between two experimental data charts (Fig. 11), then maximal normal forces raises till 474 kN. It means, that created freight wagon computer model, railway track model, simulation conditions and obtained results can be used for Sound power level calculations research.

4 Mathematical Model of Sound Power Level Changes Caused by the Contact of Wheel with Flat The noise of the whole moving wagon is comprised of the noise caused by the wheel and track construction [8]. The noise caused by the wheel is 7 dB lower than sound from other sources. However, their importance is different depending on the frequency. The work [9] determines three sound power level frequencies that are impacted by the rolling forces caused by the wheel defects, rolling surface roughness and axle bearings. The wheel defects have the biggest impact in low frequency waves. From 125 to 300 Hz. This is confirmed by works [10, 11] that determine the mathematical formula of repetition period of the turning and punching forces of wheel defect to the rail: T¼

lr  lp ; v

ð1Þ

where lr – wheel length; lp – defect length; v – wagon speed. v ¼ xlr ;

ð2Þ

v x¼ ; r

ð3Þ

where x – wheel angular speed.

where r – wheel radius. Considering this the wheel defect impact frequency to the rail is: f ¼

1 : T

ð4Þ

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When the wheel radius is 0.475 m, wagon speeds are 30 km/h, 40 km/h, 50 km/h, 60 km/h, 70 km/h, 80 km/h, defect length is 0.0161 m (161 mm), impact repetition periods T are correspondingly 0.3575 s, 0.2673 s, 0.2134 s, 0.1777 s, 0.1529 s, 0.1336 s, frequencies are 2.7975 Hz, 3.7413 Hz, 4.685 Hz, 5.6288 Hz, 6.5389 Hz and 7.4826 Hz. These repetition periods and frequencies in sound power level changes must be noted. Sound power level is calculated [12] considering full sound source energy W (radiated in all directions during the period of time), its value is calculated using the formula:  Lw ¼ 10log10

 W : Wref

ð5Þ

If benchmark energy Wref , normally 1012 W. The vibration theory allows to substitute the sound source energy W (radiated in all directions during the period of time) with other parameters that have linear dependency on energy. Assuming that: W ¼ W ðQÞ; and ¼ / Q; o Wref ¼ / Qref ;

ð6Þ

where Q – is the normal force; Qref – benchmark normal force; / – dependency factor. Values (6) in (5) give:  Lw ¼ 10log10

 Q : Qref

ð7Þ

5 Calculation Results The calculations indicate that the impact forces repeat in periods and frequencies determined by the formula (1), this is seen from the charts (see Figs. 4, 5, 6 and 7). It is also determined that wagon wheel with such defect loses contact with rail, except for wagons moving at 8.3 km/h. Results obtained by including Sect. 3 results to the formula (7) are given in chart No. 12. When the speed is 22.2 m/s and the wagon is loaded (Fig. 12a) the maximum sound power level change during the impact is 7.27 dB, empty wagon (Fig. 12b) – 8.62 dB. When the speed is 8.3 m/s and the wagon is loaded (Fig. 12c) – 4 dB, empty wagon (Fig. 12d) – 8 dB. Analysis of the data shows that the sound power level changes are bigger for the empty wagon. In theory, these sound power level changes can be used to detect the wheel defects. Therefore this model and the results will be used for further research, e.g. creation and performance of physical experiment methodology foreseen in 2019. It is also noted that the low speed stimulates the wheel hopping.

Soud Power level, dB -15.00

-1.00

-2.00

-2.00

-4.00

-8.00 1.5005 1.6222 1.7442 1.8665 1.9882 2.1104 2.2322 2.3542 2.4762 2.5983 2.7208 2.8423 2.9640 3.0860 3.2082 3.3303 3.4522 3.5742 3.6961 3.8185 3.9405 4.0621 4.1845 4.3063 4.4286

-5.00

1.5040 1.6220 1.7404 1.8580 1.9762 2.0948 2.2120 2.3302 2.4480 2.5660 2.6842 2.8022 2.9202 3.0385 3.1562 3.2741 3.3921 3.5101 3.6281 3.7462 3.8642 3.9822 4.1000 4.2187 4.3360

Soud Power level, dB

Sound Power level, dB

1.5023 1.6282 1.7540 1.8800 2.0062 2.1322 2.2583 2.3841 2.5105 2.6361 2.7621 2.8881 3.0141 3.1407 3.2661 3.3921 3.5180 3.6442 3.7703 3.8961 4.0220 4.1480 4.2742 4.4005

-5.00

1.5022 1.6240 1.7460 1.8682 1.9903 2.1120 2.2345 2.3562 2.4789 2.6004 2.7224 2.8447 2.9660 3.0880 3.2100 3.3320 3.4543 3.5760 3.6983 3.8200 3.9427 4.0642 4.1863 4.3090 4.4305

Soud Power level, dB

Simplified Mathematical Model of Changes in Sound Power Level Caused 453

10.00 5.00

0.00

-10.00

-15.00 Time, s

10.00 a)

5.00

0.00

-10.00

Time, s

5.00 b)

4.00

3.00

2.00

1.00

0.00

Time, s

10.00 c)

8.00

6.00

4.00

2.00

0.00

-6.00

Time, s

d)

Fig. 12. Sound Power level acting on first left wheels with flat: (a) loaded wagon at 22.2 m/s speed; (b) empty wagon at 22.2 m/s speed; (c) loaded wagon at 8.3 m/s speed; (d) empty wagon at 8.3 m/s speed.

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6 Conclusions 1. The simplified mathematical model of defective wheel created in this work is precise enough to determine the size of perpendicular forces caused by the contact of wheel and rail. Comparison of the model results with the results of physical experiments confirms that the model can be used to perform simplified calculations. 2. Periods and frequencies of the forces caused by the defective wheel that are determined in this work match the theoretical and physical experiments. 3. Simplified mathematical model of changes in sound power level caused by the perpendicular forces that arise when the rail contacts the wheel with flat and theoretical defect parameter calculation method and algorithm were developed. When determining the defects it is mandatory to consider the repetition periods and frequency of sound power level changes. 4. This model, method and their results will be used for further research that are foreseen in 2019–2020, i.e. creation and implementation of methodology for physical experiment.

References 1. Uzzal, R.U.A., Ahmed, A.K.W., Rakheja, S.: Dynamic analysis of railway vehicle-track interactions due to wheel flat with a pitch-plane vehicle model. J. Mech. Eng. 39(2), 54–62 (2008) 2. Hou, K., Kalousek, J., Dong, R.: A dynamic model for an asymmetrical vehicle track system. J. Sound Vib. 267, 591–604 (2003) 3. Mazilu, T.: A dynamic model for the impact between the wheel flat and rail. UPB Sci. Bull. Ser. D: Mech. Eng. 69(2), 45–58 (2007) 4. Žygienė, R.: Geležinkelio riedmenų ratų su pažaidomis ir bėgių sąveikos dinaminių procesų tyrimas. Technika, Vilnius (2015) 5. Alemi, A., Corman, F., Lodewijks, G.: Condition monitoring approaches for the detection of railway wheel defects. Proc. Inst. Mech. Eng. Part F: J. Rail Rapid Transit 231, 961–981 (2016) 6. Laboratory of Computational Mechanics. Simulation of Rail Vehicle Dynamics. http://www. universalmechanism.com/download/80/eng/08_um_loco.pdf. Accessed 21 Dec 2018 7. Riedmenų ratų geometrijos ir riedėjimo paviršiaus defektų keliamo pavojaus įvertinimas. UAB “Riedmenų ir geležinkelio kelio sąveikos bandymų centras”, Vilnius (2017) 8. Thompson, D.: Railway noise and vibration: the use of appropriate models to solve practical problems. In: The 21st International Congress on Sound and Vibration, Beijing (2014) 9. Thompson, D., Wu, T., Armstrong, T.: Wheel/rail rolling noise – the effects of nonlinearities in the contact zone. In: Tenth International Congress on Sound and Vibration, Stockholm (2003) 10. Kogan, A.: Vozdejstvie na put poezdov, imejuschih v svoem sostave vagony s polzunami na klesnyh parah. Vestnik VNIIZT 3, 3–5 (2014) 11. Bondarenko, V., Skurihin, D.: Sistema akusticheskogo kontrolia kolesnyh par vo vremq dvizenija. Mir Transporta 1(56), 192–197 (2015) 12. Thompson, D., Jones, C.: Noise and vibration from railway vehicles. In: Iwnicki, S. (ed.) Handbook of Railway Vehicle Dynamics, pp. 279–325. Chemical Rubber Company Press, London (2006)

The Challenges and Opportunities for Road Freight Transport Edvardas Liachovičius1 and Viktor Skrickij2(&) 1

2

Girteka Logistics, 03154 Vilnius, Lithuania [email protected] Faculty of Transport Engineering, Vilnius Gediminas Technical University, 10223 Vilnius, Lithuania [email protected]

Abstract. In this paper, the external factors beyond the area of influence of the European Union (EU) road freight transport, which may have a direct/indirect effect on current and future activities and procedures are under review. The outcome of this investigation is the review of challenges and opportunities that road freight transport sector encounters. Four main tendencies were identified: the proliferation of electronic business, driver shortage problem, market digitalisation, the shift from road transport to rail. These industry trends are identified and described, considering political, legal, economic, social, technological and environmental factors. Keywords: Road freight transport
Challenges
Strategies and trends
SWOT analysis

1 Main Challenges in Transport Sector As well as being a key sector of the economy, transport is a major contributor to the economy. Each year it generates €548bn or 4.8% of Gross Domestic Product (GDP) overall for the 28 EU countries. Also, the transport sector sustains over 11 million jobs in Europe. Major challenges that European Commission (EC) highlights for the whole sector are: congestions, oil dependency, greenhouse gas and particle emissions, infrastructure, competition [1]. Congestion currently is the most important problem of transportation in urban areas. There are different strategies for decreasing congestions. Some of them require a political decision, such as increasing the attractiveness of public transport, via private cars taxation or in a different way. Another solution is congestion pricing schemes from a supply perspective, improving the bottlenecked link’s traffic capacity; it is costefficient for traffic control [2]. An effective solution is shared autonomous vehicles technology [3, 4], but it requires time and investments for development and spread. These days fuel consumptions form one of the main parts of vehicle maintenance costs. In this situation, most of the EU countries are highly dependent on imports of oil [5]. Also, the oil demand in the growing economies outside the EU will increase in future; there is a prognosis that China’s dependency on foreign oil will exceed 80% by 2030 [6]. As a result, prices for transportation services can rise significantly, so alternatives need to © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 455–465, 2020. https://doi.org/10.1007/978-3-030-38666-5_48

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be found. Average daily miles of travel are growing significantly for last decades; this has a negative effect on emission. According to White Paper [7], greenhouse gas (CO2) emission should be reduced drastically soon. But the actual situation is different. The air quality situation in many cities around the world has not sufficiently improved for some pollutants, and significant exceedances are still found [8]. Impact of the transportation sector on pollution and emissions is very high, it generates about 23% of global CO2 emissions [9] and fleet change from conventional to zero emission, is not as fast as it was predicted previously, so the solution needs to be found. Additionally, it needs to be stated that Europe’s regulation of passenger car emissions has been proven to have failed when it comes to nitrogen oxide emissions (NOx) by diesel engines [10]. The main problem of diesel engines is NOx emissions that have the highest proportion of diesel pollutant emissions with a rate of more than 50% [11]. After NOx, particulate matters (PM) has the second highest proportion in pollutant emissions. Previous studies have shown that there is a strong link between exposure to PM10-2.5 and mortality [12–15]. Diesel engines met great resistance in society since Volkswagen scandal [16]. As a result, the number of diesel engines will decrease significantly shortly. Another important objective of the EU is to help establish a transport system that enhances the competitiveness of European countries [7]. Right now, infrastructure quality is uneven across the EU, and new investment projects are needed. Purwanto et al. [17] emphasise the importance of the ability to reproduce or recalculation of the assessment results of large infrastructure projects or projects that are co-financed by the EC and that model, inputs and all related documents be available to the public. As competitive conditions are tightening, new strategic projects should be analysed in a complex way, taking into account aspects of land use change posed by climate [18] to logistics hub location for empty running rate minimisation. Infrastructure switch should be made to change conventional infrastructure elements to new ones with integrated Intelligent Transportation Systems (ITS) solutions. The EU’s transport sector faces artificial barriers inside the EU, so additional deregulation is needed. But the main attention should be switched to growing competition from fast-developing transport markets in other regions. For a better understanding of sector challenges and opportunities, the current situation in EU road freight transport is reviewed, taking into account financial aspects. External factors beyond the area of influence of the EU road freight transport, which may have a direct/indirect effect on road freight transport are analysed, and four-factor groups are determined. Based on the literature review identification of road freight transport strategies and trends is presented.

2 The Current Situation in EU Road Freight Transport The logistics market of 28 member countries of the EU evaluated more than 900 billion euros in 2014 [19], distribution by country is presented in Fig. 1. 26% of all market value had belonged to Germany, France had 13.8%, United Kingdom 10.6% respectively. The total contribution of the first ten countries was 87.4%. The logistics market consists of different transport modes: water, air, pipeline and inland transport. Inland

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250 200 150 100 50 0

Germany France United Kingdom Spain Italy Netherlands Poland Belgium Sweden Finland Greece Austria Denmark Czech Rep. Romania Portugal Ireland Hungary Slovakia Luxemburg Bulgaria Latvia Lithuania Estonia Croatia Slovenia Cyprus Malta

Logistics market size in Europe, billion euros

transport has three additional modes: railways, inland waterways and road. Road transport continues to have the largest share of EU freight transport performance among the three inland transport modes [20]. It accounted for over three-quarters of the total inland freight transport (based on tonne-kilometres performed). And fluctuations are relatively small (maximal 1.7%). The share of inland water transport is a little more than 6% and not all the EU members have such a transport mode. The share of the railway is about 18%. Value of freight road transport in 2017 was €326,053 million after it grew by 4.5%, in nominal terms excluding inflation.

Fig. 1. Logistics market size [21].

Revenue, million euros

Market consolidation is very small, top 10 European road freight transport providers (Fig. 2) generates only 10.8% of the market revenue. Most individual truck operators are small firms. Meaning over 90% of EU road freight businesses has less than ten employees [19].

7000 6000 5000 4000 3000 2000 1000 0

Fig. 2. Revenue of top 10 European road freight transport providers [19].

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In Fig. 3 type of goods transported by road freight is presented. In terms of tonnekilometres, the major product groups were food products, beverages and tobacco (17% in total); agriculture, forestry and fishery products 11%; a mixture of different types of goods which are transported together 10%; metal ores and peat 8%. Four groups: (i) wood and wood products (except furniture), pulp, paper and paper products, printed and recorded media; (ii) chemicals and chemical products, rubber and plastic products; nuclear fuel; (iii) other non-metallic mineral products; (iv) basic metals and fabricated metal products (except machinery and equipment) had 7% each. Secondary raw materials, wastes and transport equipment had 4% each, machinery and equipment, as well as coke and refined petroleum products 3% each. Remaining positions were 12% in total. The main amount of these cargoes are transported by 10member state countries: Poland (28.2%); Spain (11.0%); Germany (6.8%); Romania (5.4%); Netherlands (5.2%); Slovakia (4.7%); Hungary (4.3%); Bulgaria (4.3%); Czech (4.3%); Lithuania (4.3%) and other countries share the rest 21.5%. Agriculture, forestry and fishery products Metal ores and peat

11%

12%

8%

10% 4%

17%

4% 3%

7% 7%

7% 7% 3%

Food products, beverages and tobacco Wood and wood product, paper, printed media Coke and refined petroleum products Chemicals and chemical products, rubber, plastic, nuclear fuel Other non metallic mineral products Basic metals and fabricated metal products Machinery equipment Transport equipment Secondary raw materials wastes Mixture of different types of goods Other

Fig. 3. EU Road Freight by type of goods in 2016, tonne-kilometres (Authors scheme based on [26] data).

3 Key Challenges and Opportunities in the EU for Road Freight Transport In this chapter, basic external factors beyond the area of influence of the EU road freight transport, which may have a direct/indirect effect on road freight transport are analysed. Four-factor groups are determined: (i) political and legal; (ii) technological; (iii) social and environmental; (iv) economic. 3.1

Political and Legal Factors

Political factors include national and EU interventions in the market, such as taxes, tariffs, trade barriers, market regulation, as well as issues related to public infrastructure [22]. Legal factors combine social, safety and security regulations and administrative

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procedures. They are oriented on consumer and comprise social laws, health and safety regulation, as well as competition rules. Political and legal factor are combined, whereas some aspects as restrictions of working time are social, but regulated through political decisions. Transport industry (de-)regulation is one of the major political factors. Main changes that may affect freight transport are presented in White paper [7]. According to proposed strategy, freight shipments over short and medium distances (below some 300 km) will, to a considerable extent remain on trucks in the future. In longer distances freight multimodality has to become economically attractive for shippers. Railways can be a solution, but privatisation and deregulation are needed. For liberalisation of this segment since 2001 four Railway Packages has been established. For road transport, the EC established Mobility Packages. They include road charging and tolling questions, drivers rest time, posting, vehicle taxation, emissions, access to market, infrastructure, clean vehicles, digitalisation. Questions related to drivers’ work and rest time and place, as well as salary aspects, are highly regulated and cause a lot of discussion between member states with different salary rates. Among the controversial reforms in the package is a compulsory return of drivers to their country of origin for their monthly rest. Trade barriers between the Central European and the periphery countries such as Poland, Romania, Bulgaria, Czech Republic, Lithuania, appears, as economically ineffective. Greenhouse gas emission decrease is also presented in White Paper, but EU regulation in the field of carbon dioxide from heavy vehicles appeared only in 2018. According to COM 284 [23], EU’s fleet of new heavy-duty vehicles shall be reduced compared to the reference CO2 emissions as follows: (i) from 1 January 2025 to 31 December 2029 by 15%; (ii) from 1 January 2030 onwards by at least 30%. Taxation in road freight transport depends on two parameters. First one depends on carrier registration country (VAT, income tax, charges associated with the vehicle registration, etc.). The second one depends on the route selected (toll, parking fees, etc.). The tax burden and charges in road freight transport are significantly different in EU countries [24]. According to 2017 data, tolls in France for a 40-tonne heavy goods vehicle (HGV) where €9,624 in Slovakia €16,300; vehicle insurance in France €2,248 in Slovakia €2,980 [19]. Driver cost in France €47,758 in Slovakia €27,934. EU transport infrastructure policy of the EU comprises the TEN-T core network, comprising nine major corridors which will connect different transport modes [22] and cross-border projects such as Silk Road Economic Belt, also known as One Belt One Road initiative (OBOR). Additional infrastructure development will be required for the vision of accident-free driving in Europe via cooperative ITS based on vehicular communication [25]. Safety and security regulations affect the freight transport sector by ensuring the free movement of goods throughout the EU. Also, some limitations appear as gross vehicle weights, vehicle dimensions, etc. 3.2

Technological Factors

Road freight transport as part of the transport sector is currently confronting immense change; and like all changes, this brings both risks and opportunities. Research and

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development (R&D) activity were not common in the logistic sector until now, but it may increase the competitiveness of companies significantly. Investigations include not only R&D activity but technology development, together with innovation implementation [22]. Few innovative technologies can change the whole sector drastically. Most of them are linked with digitalisation. The first technology that may change the paradigm of transportation is 3D printing. It may change the type of goods need to be transported, from the product to material. Manufacturing may be located near the end user. The second technology that may change the transportation process is autonomous vehicles. This technology solves several problems; one of them is the shortage of drivers. The second one is the safety of the elimination of the human factor. The realisation of platooning systems and optimal driving regimes selection will lead to a reduction of fuel consumptions and emission level. The 4th industrial revolution needs to be kept in mind, as well. Plants without human beings became a reality, automation level increases in logistics warehouses too. Discussed examples include physical technologies; the second part is software solutions. Starting from software as a service, when it is based in the cloud, and user use and pay for it only when needed. Second is data analytics; it includes Big Data during information analysis. As a result, decision making is made based on Big Data analysis and time lag decreases significantly. As the sector is becoming increasingly dependent on software, cybersecurity became an important factor. One of perspective technology can be used for safety increase is Blockchain. 3.3

Social and Environmental Factors

The social effect depends on demographic growth and structure, cultural aspects, consciousness such as health, and environmental. Covering ecological and other aspects such as climate change, transport externalities (noise emissions and air pollutants), energy and environmental legislation. The total population of the EU (28 member states) is expected to increase by approximately 2.2% between 2013 and 2030 (from 507.2 m to 518.5 m inhabitants). But society is ageing, the share of the total population aged 65 or above in 2010 was 17.4% prognosis for 2030 is 23.6% [22]. This factor will lead to changes in social and consumer behaviour characteristics, but not so much as technological achievements. The proliferation of electronic business may be a decisive factor. More and more companies are moving into virtual space. In terms of employees, there is a lack of truck drivers all over the world. In Truck Driver Shortage Analysis presented in 2017, there were more than 63,000 free vacancies in the US; and this number is increasing. The same situation is in the EU; there are 52,000 free vacancies in the UK; 45,000 in Germany and 20,000 in France [19]. Self-driving trucks may be a solution, but then the company’s office structure will change. Managers working with drivers should switch to human-robot communication. Digitalisation also will have an impact; Big Data analytics will allow responding to challenges almost in real time. This will give a competitive advantage to companies that will use this technology. As a result, the demand for Information Technology professionals will increase.

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Economic Factors

Comparing countries by GDP value, it can be seen that the EU is second in the world after the US. According the World Bank data, GPD of EU is $17,282bn; GPD of US is $19,391bn and third place is covered by China with $12,238bn [27]. Main internal risks are Brexit and formation of a populist government in some member states. Despite this, the wealth gap inside the EU countries is decreasing and the economy is growing. Such a situation expected to influence the logistics sector by changing the demand patterns of consumer goods and the spatial structure of production [22]. Increased trade volumes outside the EU due to globalisation processes will positively affect economics. There is a prognosis that up to 2040 Europe contribution to the global growth comparing to 2012 will be 16.8%. The leader will be China with 31.8%; the US will increase by 22.9%, India and Brazil will be along with the leaders [22]. The biggest impact for road freight transport may have OBOR initiative proposed by China. The main effect from the new road between Europe and Asia will go to the railway sector, together the demand for road freight transport will increase too. EU needs to import raw materials; their scarcity in future will increase. Probably fossil fuel scarcity will be problem number one talking about raw materials. As a result, the energy cost will increase. Solutions need to be found to decrease these risks, together with decreasing transport-related emissions. In a global approach, climate change needs to be minimised.

4 Identification of Road Freight Transport Strategies and Trends The road freight transport sector is facing major changes and opportunities (Table 1). Favourable economic cycle in the EU had a positive effect on road freight transport sector during the last years. For the period from 2012 to 2016, the number of new vehicles in fleet increased by almost 6% up to 22%, according to Eurostat data [20]. The number of 2 and 3 years old vehicles increased by about 2% each; and quantity of 4–7 years old vehicles decreased. EU is a relatively young union; the monetary union was established only in 1999. For the last 15 years, few candidate countries became member states. As a result, market size grows significantly as well as the EU population. This aspect had a positive effect on transportation companies; they had an opportunity to refocus from domestic markets to international. As living standards in new member states are lower and road transportation business is international, new EU members became highly competitive in this segment. As it was identified in Sect. 2, over 90% of EU road freight businesses have less than ten employees. The largest market share in the transport sector belongs to medium and small business and it is a strength. Access to this market is relatively simple and no special skills are required. There are two main types of companies working in the logistics sector. First is asset-based companies where transportation services are provided using internal trucks. Second is freight forwarding companies, that professionally organize customer’s cargo transportation, but does not provide transportation services itself. Own capital

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requirements for the second type of companies is minimal; as a result, competition is high in this segment. For assets based companies, the initial capital is needed. The price of the truck in the secondary market is about 40,000 Euro. Also, other costs need to be taken into account. The main challenges facing small companies is to work through intermediaries. Often customers work directly with large companies, and as a result profit of small players is falling. Vehicle maintenance in such company is relatively expensive as there is no access to vehicle manufacturers. Table 1. SWOT analysis of road freight transport in the EU. Strengths • Economic activity/GDP increase • EU market enlargement; • EU population increase • Low barrier to enter the market; • Highly fragmented European Transportation Market; • Relatively new vehicle fleet Opportunities • Autonomous vehicles; • Digitalisation; • The proliferation of electronic business

Weaknesses • Ageing society • Shortage of drivers and wage pressure • Lack of R&D innovations for the industry; • Infrastructure quality is uneven across the EU; • Transport-related emissions and climate change; • Fossil fuel scarcity Threats • Double standards in regulation; • Shift from road transport to rail; • Change of transportation paradigm

Ageing Society in the EU is one of the weaknesses, which will affect all the economy. The second problem directly linked to the transport sector is the shortage of drivers all over the member states. Thus wage pressure is increasing for companies. R&D innovations are not used widely in sector, lagging other areas are noticeable. These activities must be promoted shortly. The digitalisation of the transport sector is an opportunity that can change the whole paradigm of transportation and one of the areas where R&D can be implemented. Big Data analysis will allow responding faster to challenges, increasing the competitive advantage of companies. The autonomous vehicle is another technology, that may solve different problems; it is expected to decrease the number of accidents eliminating the human factor. In the freight transport sector, it may solve the drivers’ shortage problem. A dominant number of road freight transport has diesel engines, which have a negative impact on the environment and affect climate change. Scarcity of fossil fuel will increase shortly; one of the factors affecting this is the Chinese economy, as it is growing faster than EUs. Environmental requirements are promoted mostly through regulatory activities. In 2018 European Commission firstly prepared regulation regarding greenhouse gas emissions for freight road transport and such measure is justified. Threats can be found in regulation. For example, some EU regulations can reduce competitiveness for companies located in Eastern Europe. For example, in COM 277 [28] article 8b is added to further specify the obligation on transport undertakings to organise the drivers’ work in such a way that they can return to their home for a weekly

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rest at least once within three consecutive weeks. A well-known fact is that many drivers working in Western Europe are from Eastern Europe. And drivers working in Eastern Europe are from third countries. In the first case, such a decision will not have a negative effect on ecology, because there is a lot of orders in this region. In the case of Eastern Europe, the rate of empty running will increase significantly. Companies may solve this task setting up new offices in Western or Central Europe countries, and the driver will travel home without a truck, but then the tax payment country will change. Shift from road transport to rail is another area where new threats may appear. It is desired that on the routes of up to 300 km cargo will be transported with road transport, for longer distances rail will be used, this will require additional infrastructure. In countries where rail passenger transport is popular, cargo transportation will be complicated because passenger trains have priority and transportation time for cargoes will increase. Max freight vehicle weight in most of EU member states is 40 tonnes, at the same time in Finland vehicles with a maximum weight of 76 tons and 9-axles are used. This allows to reduce emissions, and several axles distribute loads evenly without damage of the road pavements. But such alternative solutions are not taken into account by the EC. The main thread for individual companies remains technological achievements. In future transport services going to reach a much higher level, and companies who will not be able to re-orient will lose markets.

5 Conclusions Summarising the review of the challenges and opportunities for road freight transport, four main tendencies were identified: 1. The proliferation of electronic business may be a decisive factor shortly. More and more companies are moving into virtual space. 2. Road freight transport faces with driver shortage problem, and the situation is getting worse every year. Autonomous driving may be a solution, but fully autonomous vehicles are expected in the market only by 2030. 3. Another important aspect is the market digitalisation. Implementation of data analytics will lead to productivity increase and optimisation of the operations. 4. Shift from road transport to rail is another area where new threats for road freight transport may appear. It is desired that for longer distances rail will be used, this will require additional infrastructure.

References 1. EU transport policy. https://europa.eu/european-union/topics/transport_en. Accessed 21 Jan 2019 2. Chen, D., Ignatius, J., Sun, D., Goh, M., Zhan, S.: Impact of congestion pricing schemes on emissions and temporal shift of freight transport. Transp. Res. Part E 118, 77–105 (2018)

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3. Mounce, R., Nelson, J.D.: On the potential for one-way electric vehicle car-sharing in future mobility systems. Transp. Res. Part A 120, 17–30 (2019) 4. Levin, M.W.: Congestion-aware system optimal route choice for shared autonomous vehicles. Transp. Res. Part C 82, 229–247 (2017) 5. Palazuelos, E., Fernandez, R.: The importance of transnational corporations in the supply of oil to Europe: implications. Energy Policy 47, 270–281 (2012) 6. Wang, Q., Li, S., Li, R.: China’s dependency on foreign oil will exceed 80% by 2030: developing a novel NMGM-ARIMA to forecast China’s foreign oil dependence from two dimensions. Energy 163, 151–167 (2018) 7. White Paper: Roadmap to a single European transport area – towards a competitive and resource efficient transport system, p. 30 (2011) 8. Horizon 2020: Work Programme 2018–2020 Smart, green and integrated transport, p. 109 9. Liu, Z., Li, L., Zhang, Y.J.: Investigating the CO2 emission differences among China’s transport sectors and their influencing factors. Nat. Hazards 77, 1323–1343 (2015) 10. Hooftman, N., Messagie, M., Van Mierlo, J., Coosemans, T.: A review of the European passenger car regulations – real driving emissions vs local air quality. Renew. Sustain. Energy Rev. 86, 1–21 (2018) 11. Resitoglu, I.A., Altinisik, K., Keskin, A.: The pollutant emissions from diesel-engine vehicles and exhaust aftertreatment systems. Clean Technol. Environ. Policy 17, 15–27 (2015) 12. Sosa, B.S., Porta, A., Lerner, J.E.C., Noriega, R.B., Massolo, L.: Human health risk due to variations in PM10-PM2.5 and associated PAHs levels. Atmos. Environ. 160, 27–35 (2017) 13. Zanobetti, A., Schwartz, J.: The effect of fine and coarse particulate air pollution on mortality: a national analysis. Environ. Health Perspect. 117(6), 898–903 (2009) 14. WHO, 2012: World Health Organization. IARC: Diesel Engine Exhaut Carcinogenic. http:// www.iarc.fr/en/media-centre/pr/2012/pdfs/pr213_E.pdf. Accessed 21 Jan 2019 15. WHO, 2013: World Health Organization, Regional Office for Europe. Health Effects of Particulate Matter: Policy Implications for Countries in Eastern Europe Caucasus and Central Asia. http://www.euro.who.int/__data/assets/pdf_file/0006/189051/Health-effectsof-particulate-matter-final-Eng.pdf. Accessed 21 Jan 2019 16. Li, L., McMurray, A., Xue, J., Liu, Z., Sy, M.: Industry-wide corporate fraud: the truth behind the Volkswagen scandal. Environ. Pollut. 212, 121–127 (2016) 17. Purwanto, A.J., Heyndrickx, C., Kiel, J., Betancor, O., Socorro, M.P., Hernandez, A., Eugenio-Martin, J.L., Pawlowska, B., Borkowski, P., Fiedler, R.: Impact of transport infrastructure on international competitiveness of Europe. In: World Conference on Transport Research - WCTR 2016, Shanghai, 10–15 July 2016. Transp. Res. Procedia 25, 2877–2888 (2017) 18. Mollenhauer, H., Kasner, M., Haase, P., Peterseil, J., Wohner, C., Frenzel, M., Mirtl, M., Schima, R., Bumberger, J., Zacharias, S.: Long-term environmental monitoring infrastructures in Europe: observations, measurements, scales, and socio-ecological representativeness. Sci. Total Environ. 624, 968–978 (2018) 19. European Road Freight Transport 2018. Report ID: 1459895, p. 204, November 2018 20. Eurostat. Freight transport statistics - modal split. https://ec.europa.eu/eurostat/statisticsexplained/index.php/Freight_transport_statistics_-_modal_split. Accessed 21 Jan 2019 21. Europe: logistics market size in 2014. https://www.statista.com/statistics/639897/logisticsmarket-size-europe-2014/. Accessed 21 Jan 2019 22. Fact-finding studies in support of the development of an EU strategy for freight transport logistics Lot 1: Analysis of the EU logistics sector Final report. European Commission, p. 442 (2015). https://ec.europa.eu/transport/sites/transport/files/themes/strategies/studies/ doc/2015-01-freight-logistics-lot1-logistics-sector.pdf. Accessed 21 Jan 2019

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23. COM 284 (2018) Regulation of the European Parliament and of the Council setting CO2 emission performance standards for new heavy-duty vehicles, p. 47 24. Konečný, V., Semanova, S., Gnap, J., Stopka, O.: Taxes and charges in road freight transport – a comparative study of the level of taxes and charges in the Slovak Republic and the selected EU countries 65(4), 208–212 (2018) 25. Weiß, C.: V2X communication in Europe – from research projects towards standardization and field testing of vehicle communication technology. Comput. Netw. 55, 3103–3119 (2011) 26. Energy, transport and environment indicators, p. 232 (2018) 27. The World Bank (2018). https://data.worldbank.org/indicator/NY.GDP.MKTP.CD. Accessed 21 Jan 2019 28. COM 277 (2017). http://ec.europa.eu/transparency/regdoc/?fuseaction=list&coteId= 1&year=2017&number=277&version=ALL&language=lt. Accessed 21 Jan 2019

Organization of Damaged Road Rehabilitation in the Village of Rybany Peter Durech

and Zdenek Dvorak(&)

University of Zilina, 1 Maja 32, Zilina, Slovakia [email protected], [email protected]

Abstract. The current-state assessment of the organization of the rehabilitation of roads damaged by emergency in the Slovak Republic is an extensive issue. The article addresses rehabilitation of the road damaged by the most common extraordinary event in the municipality. The contribution of the article is a new proposal for the organization of the damaged road rehabilitation in the selected village of Rybany. The aim is to increase the required level of safety of the population and to reduce damage to residential buildings and roadways located in the village. Keywords: Extraordinary events


Rehabilitation
Safety level
Roads

1 Introduction Nowadays, various emergencies with negative effects often causing major damage to the roads in municipalities are becoming common. Over the last few years, Central Slovakia has been hit by large destructive floods which caused major damage to residential buildings and roads in the municipalities of the Trenčín region. These negative events, which endangered the lives of the region’s inhabitants, were an inspiration for writing this article. The respective problem was applied to the village Rybany, which was hit by these floods in the past. The new proposal of the organization of the damaged road rehabilitation in Rybany will increase the safety of the local population in the future. The aim of the article is to present the results of the research, which was carried out in the form of a case study. Its goal was to prepare a scenario that will effectively solve the problem of rehabilitation of roads damaged by floods, considering the time and financial aspects.

2 Analysis of the Municipality Characteristics of Rybany Rybany is one of the developed villages in the district Banovce upon Bebrava. It is located in the Trenčín Region, specifically in its northeastern part. There are all engineering networks, public water supply, and sewerage. It lies in the climatic area of western Slovakia, with a mild climate. Frequent rains in summer often result in floods [1].

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 466–473, 2020. https://doi.org/10.1007/978-3-030-38666-5_49

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The village of Rybany lies on the left bank of the Bebrava river. Its minor declivity in the area has periodically caused it to spill over its banks. This primarily threatens the local population, which is currently around 1,460 [2] (Fig. 1).

Fig. 1. Map of the flow threat for the village of Rybany – 100-year water (Based on https:// mpompr.svp.sk/data/3_banovcenadbebravou_rybany_bebrava-35-41-04_h100.pdf).

In 2016, there was a large flood in the village and its surroundings, which caused extensive damage. This crisis event was caused by the flooding of the Bebrava River. In the future, the same or even worse crisis event can occur, which can seriously damage the roads in this village and, last but not least, endanger the security and lives of the population. 2.1

Causes of Road Damage

In the territory of the Slovak Republic, roads can be damaged by the following crisis events: • • • • • • • •

floods, landslides, earthquakes, snow avalanches, terrorist attacks, industrial accidents, nuclear power plant accidents, war conflicts.

Several statistical sources indicate that the main cause of road damage in the Slovak Republic is floods. Other causes of damage may include flood waves, subterranean

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landslides, landslides. In our territory, floods occur mainly due to extreme precipitation, rapid warming in the case of high snow reserves in the catchment area, torrential rainfall, but also due to strong warming of frozen water streams. Two years ago, the village of Rybany was hit by a massive flood that flooded half of the village. The cause of the flood was flooding of the river Bebrava, which borders the left side of the village. To assist with the floods, the Fire and Rescue Corps were summoned, as well as all volunteer fire corps from the surrounding villages. A flood protection barrier was built to protect the village against further flooding of the Bebrava River. The duration of the flood was several days, resulting in paralyzing the village traffic, chaos, and constant power outages. Due to large floods, transit traffic had to be diverted to the surrounding communities. Bus traffic had regular delays due to diverted routes that had to bypass the flooded area. The floods caused damage to large numbers of residential and farm buildings, as well as village roads [3–6].

3 Case Study – Analysis of the Proposal for Road Rehabilitation in the Village of Rybany The road selected for rehabilitation is in the village of Rybany, and it is a 2nd class and a 3rd class road. The reason for the selection was the recent floods caused by flooding of the Bebrava River. The total length of this road is approximately 1.4 km (see Fig. 2). The first part of the selected road begins at the beginning of the Rybany village from Banovce and continues until the intersection. The length of this part, which is a 2nd class road no. 592, is 735 m. The total length of the road of the 2nd class no. 592 is 12.267 km and it passes through the districts of Banovce nad Bebravou and Partizanske. The second part of the road begins at the intersection, continues towards the Borcany village, and ends at the end of the village of Rybany in front of a road bridge that passes over the Bebrava River. It is a 3rd class road. The length of this road is 665 m [7, 8].

Fig. 2. The road in the village of Rybany selected for reconstruction (source: own processing).

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Transport Routes. We selected the route Zlobina - Rybany. The route leads along the 1st class road no. 50, along the 2nd class road no. 592 and a 3rd class road. The quarry Zlobina is situated in the Trenčín Region. The distance from the Zlobina quarry to the place where the necessary material will be transported, i.e. Rybany is approximately 16 km (see Fig. 3).

Fig. 3. Material transport route.

Transported Material. The material to be transported will be of 0/16 and 16/32 fractions, from the Zlobina quarry, near the town of Banovce upon Bebrava. The material of fraction 0/16 is a dolomite aggregate that will be transported to restore the protective layer, and the fraction 16/32 material is also dolomite aggregate and will be used to restore the road subbase. Characteristics of the Material for the Rehabilitation of the Selected Road. The proposed road is a 2nd class and a 3rd class road. These types of roads have different characteristic properties. In the Slovak Republic, the width of the 2nd class road is 9.5 m and of the 3rd class road, it is 7.5 m. For this reason, the material transport routes for the rehabilitation of the 2nd class road and the 3rd class road were designed separately. For road rehabilitation, we propose the transport of the material for the overall rehabilitation of two layers: subbase and the protective layer. The subbase thickness is 0.4 m and the thickness of the protective layer is 0.15 m. For the total subbase rehabilitation, the material of fraction 16/32 is used, and for the protective layer, it is the material of the fraction 0/16. Characteristics of the 2nd Class Road. For one meter of the road subbase, 3.8 m3 of material, fraction 16/32, is required. When converted to tonnes, 5.4 tonnes of material per one meter of subbase will be needed. For the entire 2nd class road length, approximately 3,994 tonnes of material, fraction 16/32, will be needed. The amount of material to rehabilitate one meter of the protective layer is 1.4 m3 of fraction 0/16. In terms of tonnage, it is 2.2 tonnes of material. For the total

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rehabilitation of the 2nd class road or 735 m, approximately 1,645 tonnes of fraction 0/16 material will be needed. Characteristics of Rehabilitation of a 3rd Class Road. The second part of the designed route, which is a 3rd class road, is 665 meters long. For 1 m of the road subbase, 3 m3 of material, of fraction 16/32 will be needed. Converted to tonnes, this amounts to 4.29 tonnes. For the entire 3rd class road length, we will need approximately 2,853 tonnes of material, fraction 16/32. To rehabilitate the protective layer of onemeter length, 1,125 m3 of material, fraction 0/16, will be needed. After calculation that is 1,766 tonnes. For the whole road section of the 3rd class, approx. 1,175 tonnes of fraction 0/16 will be necessary. Place of Loading. The material needed will be supplied by the Zlobina quarry. Road communications to the loading site are reinforced and suitable for semi-trailers. The quarry machines will load the vehicles which will then transport the material for the rehabilitation of the road in Rybany. Place of Unloading. The place of unloading will be a storage site, near the damaged road in Rybany. From there, the material will be transported directly to the road construction site. The storage site has a flat concrete base, so it is suitable for semitrailers, e.g. Renault 430 dxi. Its dimensions are suitable for material unloading and semi-trailer turning. It is located at the beginning of Rybany, in the direction from the town of Banovce upon Bebrava. Means of Transport. The transportation will be provided by the transport company CND-Urbanovsky, which we selected. The company’s headquarters are in Trencin. This company deals with road freight transport, more specifically the transport of bulk material. They participated in the construction of various roads and roadwork. The transport of material on the roads between the Zlobina quarry and the storage site on the damaged road in the village of Rybany will be provided by four Renault 430 dxi trucks with a semi-trailer. Semitrailers can transport up to 26 tonnes of material. Moreover, the truck Liaz 150 and three Tatras T815 will be used to transport the material on the site. These trucks are more durable in difficult conditions on untreated and hard-to-reach roads. The Renault 420 dxi has a great transport weight but is not suitable for difficult conditions. Time and Economy of Transportation. For the overall rehabilitation of the subbase and the protective layer of the 2nd class road, 3,994 tonnes of fraction 16/32 and 1,644.5 tonnes of fraction 0/16 will be required. The working time of the driver will be 9 h. To keep the material supply time as short as possible, two shift-system will be used. We expect a total of 8 turns per vehicle for one day. The average vehicle speed is 60 km per hour. All four semi-trailers can achieve 32 turns per shift, i.e., 64 turns for two work shifts. They can transport 64  26 t = 1,664 tonnes of material in one day. The semi-trailer has a payload of 26 tonnes. Transportation of 3,994 tonnes of fraction 16/32 will take approximately 2.5 days. Supplying 1,645 tonnes of fraction 0/16 will last about 1 day. The total rehabilitation of subbase and the protective layer of the 3rd class road require 2,853 tonnes of fraction 16/32 and 1,175 tonnes of fraction 0/16. The transport of

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fraction 16/32 material will take approximately 1.7 days = 40 h and of the 0/16 material, the transport will take approximately 0.7 days = 17 h. The material transport time for the total rehabilitation of subbase and protection layer of the 2nd class road will last approx. 3 and a half days = 84 h. The material transport time for the overall rehabilitation of the subbase and the protective layer of the 3rd class road will last 2.4 days = 57 h. The total time for transporting the material for the complete rehabilitation of the subbase and the protective layer of the entire road will take approximately 6 days. This time includes the material for 2 layers, namely the subbase and the protective layer. The transport duration is relatively long because the road is relatively long – 1.4 km and the design of the transport technology for this road was calculated for the amount of the material needed to completely rehabilitate the subbase and the protective layer of the road. The amount of material is calculated for the complete destruction of the original road. In case of partial destruction of the road, the amount of material would be smaller and thus the transport time would be reduced. The damage can occur, for example, only in particular sections, and thus the duration of the material transport time for the road rehabilitation would be clearly reduced. The total amount of the material required will then depend on the expert inspection of the damaged road. The total number of kilometers driven by semi-trailer sets is 12,288 km. The price per tonne shipped is € 1.47. 9,667 tonnes of material were transported. The total cost of all material transportation is 14,210 €. Other costs are related to the cost of the vehicle (fuel) and the wage of the driver. The total time for transporting the material for the complete rehabilitation of the subbase and the protective layer of the entire proposed road will take approximately 6 days (Table 1). Table 1. Proposal of recovery organization in the village Rybany. Resulting table Number of transport kilometers Price per tonne transported The total quantity of transported material Total price for all material transportation Total transportation time

3.1

12,288 km 1.47 € 9,667 tonnes 14,210 € Approx. 6 days

Recommendations for Increasing the Safety of the Population

For the successful rehabilitation of the damaged road in terms of increasing the safety of the local inhabitants, we recommend focusing on these subtasks: • careful preparation of a crisis plan for the given community with real and current content, • ensuring proper transport vehicles and machinery for loading and transporting material for the rehabilitation of the damaged road, • coordination of specific tasks in the reconstruction of the damaged road, • accessibility of roads in the given area (forces and means), • preparation of the place for a storage site (Fig. 4).

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Fig. 4. Total destruction of a road by flood.

4 Conclusion The aim of the article was to demonstrate through a case study the need for timely crisis planning for the restoration of flood-damaged roads. An important part of crisis management and civil protection is the preparation of type plans and case studies for specific locations where floods can damage transport infrastructure. Optimizing these pre-crisis processes is geared towards preparing contingency plans to be addressed in all regions. Maintaining and preparing the necessary technology and training people is a continuous task of crisis management. The recovery of roads affected by an emergency is a broad subject with all its specificities as regards the reconstructed road category, the declared crisis, the extent of road damage, the deployed forces and resources, public procurement, funding, recovery levels and many other factors. The post-crisis recovery process is a time-consuming and complicated process that deserves more attention in terms of transport, material and labor organization. Improving these measures will also improve the required level of safety for the population. As part of these processes, the current problem with public procurement of services related to road renewal is currently the biggest problem. The main goal of the article was to present the results of a real case study fulfilled. The case study confirmed that the possible restoration of a destroyed road is very demanding in terms of time, money and organization [9]. Acknowledgments. Publication of this paper was supported by the Centre of Excellence for Systems and Services of Intelligent Transport II, ITMS 26220120050 and project VEGA 1/0159/19 - Assessment of the resilience level of the key elements of the ground transport infrastructure.

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References 1. Brabcova, V., Slivkova, S., Rehak, D., Toseroni, F., Havko, J.: Assessing the cascading effect of energy and transport critical infrastructure elements: case study. Commun. Sci. Lett. Univ. Zilina 20(2), 8–15 (2018) 2. Dvorak, Z., Sventekova, E., Rehak, D., Cekerevac, Z.: Assessment of critical infrastructure elements in transport. Procedia Eng. 187, 548–555 (2017) 3. Dvorak, Z., Razdik, J, Sousek, R., Sventekova, E.: Multi-agent system for decreasing of risk in road transport. In: Proceedings of the International Conference Transport Means, Kaunas University of Technology, Kaunas, pp. 100–103 (2010) 4. Dvorak, Z., Luskova, M., Cekerevac, Z.: Risk reduction in critical road infrastructure in Central Europe. In: Proceedings WMSCI 2014 - 18th World Multi-conference on Systemics, Cybernetics and Informatics, chap. 10, pp. 234–239. International Institute of Informatics and Systemics (2014) 5. Leitner, B., Luskova, M., O’Connor, A., van Gelder, P.: Quantification of impacts on the transport serviceability at the loss of functionality of significant road infrastructure objects. Commun. Sci. Lett. Univ. Zilina 17(1), 52–60 (2015) 6. Rehak, D., Hromada, M., Senovsky, P., Krocova, S., Apeltauer, T., Pidhaniuk, L.: Summary of how to assess the quality and resilience of the infrastructure. Study (2016) 7. The Central Portal of the Public Administration of the Slovak Republic. Tree list of municipalities in SR - District Banovce nad Bebravou. http://portal.gov.sk/Portal/sk/Default. aspx?CatID=104&parent=301. Accessed 1 Jan 2019 8. Welcome to Rybany. Climatic conditions. http://rybany.blog.cz/1110/klimaticke-podmienky. Accessed 1 Apr 2019 9. Vidrikova, D., Dvorak, Z., Kaplan, V.: The current state of protection of critical infrastructure elements of road transport in the conditions of the Slovak Republic, Kaunas University of Technology, Kaunas, pp. 46–49 (2011)

Criticality Assessment of Railway Bridges Zdenek Dvorak1(&) , Maria Luskova1 , David Rehak2 and Simona Slivkova2

,

1

University of Zilina, 1.maja 32, Zilina, Slovakia {zdenek.dvorak,maria.luskova}@fbi.uniza.sk 2 VSB - Technical University of Ostrava, Lumirova 630/12, 70030 Ostrava - Vyskovice, Czech Republic {david.rehak,simona.slivkova}@vsb.cz

Abstract. The paper Criticality Assessment of Railway Bridges presents current research results at the University of Zilina. Transport as part of the critical infrastructure of the state is one of the key sectors. Rail transport is one of the critical infrastructure subsectors, consisting of point, line and area objects. Rail bridges and tunnels are currently one of the most important railway infrastructures. Their disruption or failure could lead to the cessation of rail transport on the route involved and the consequent complicated provision of alternative transport. In the case of international routes, this situation would lead to significant economic losses and a negative impact on the transport serviceability of residents and freight forwarders. In order to maintain the continuity of railway transport on the most important routes, it is appropriate to identify and evaluate all critical bridges in a timely manner and to give them increased protection against identified threats. Based on this, the paper presents a tool for criterionbased assessment of the railway bridges criticality. The tool is based on the evaluation of technical and economic parameters. Technical parameters are e.g. the bridging height, the length of the bridge object, the load of the bridge object, the number of pillars, the material of the bridge object or the age of the bridge object. On the other hand, the economic parameters are focused on the economic losses or the intensity of traffic on the bridge object from the point of view of the economy or the number of transported persons. The combination of these parameters allows the evaluator to analyse the criticality of railway bridges both in terms of their structure and social contribution. Keywords: Infrastructure
Criticality
Railway
Bridge
Critical assessment

1 Introduction Railway transport is a very important type of public transport which has a longstanding irreplaceable place especially in suburban transport and transport for distances up to 400 km. Advanced railway companies offer passenger transport over high-speed lines and freight combined transport with efficient house-to-house transportation. Trans-European railways in Central Europe are usually double-tracked and electrified. Pass-through performance of these lines is at the level of 100–130 pairs of trains in 24 h [4]. When assessing the resilience of the railway infrastructure the age and other © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 474–483, 2020. https://doi.org/10.1007/978-3-030-38666-5_50

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important parameters of the construction are the key parameters. The degree of utilization of the transit railway lines capacity is close to their technical possibilities. In this context, tunnels and bridges can be considered as the most critical elements of rail infrastructure in terms of their substitutability. Identification and determination of the railway infrastructure critical elements enables early risk assessment and the adoption of adequate security measures. For this purpose, attention is paid to assessing the criticality of railway infrastructure elements. At present, there are methods based on a general approach enabling to assess any elements in the transport field e.g. [5]. Other methods are already focused specifically on the railway infrastructure, however, also in this field, general methods enabling assessment of the criticality of all elements are concerned e.g. [7, 15]. A specific part represents methods focused on the assessment of criticality of railway bridges e.g. [1]. At present such methods are not widespread, even though their usability is highly beneficial. For this reason, the aim of the paper is to present a new instrument designed to criterion-based assessing the criticality of railway bridges. The specificity of this instrument lies above all in the proposed criteria which take into account the criticality of the bridges not only on the basis of technical parameters but also from an economic point of view.

2 Theoretical Bases of Solved Problems The starting point of the problem solving is a clear and comprehensible definition of the subject of the research. For this reason, the elements of railway infrastructure, their natural and human threats and approaches to identifying these elements to define their criticality, are defined below. 2.1

Railway Infrastructure Elements

Railway infrastructure is formed by railway tracks, rail switches, other engineering structures (e.g., bridges, tunnels) and associated infrastructure of stations (e.g., platforms, security and safety devices) [6]. For the purpose of assessing criticality, it is appropriate to classify railway infrastructure objects into three groups [12, 14]: • Line elements provide transfer, delivery, or transport between two physically separated locations (i.e. connectors of individual elements). Basic line elements are track sections. • Point elements represent elements that create a concentrated and closed whole, placed on a small area (mostly individual devices and other smaller elements of the system). • Area elements have the character of an area unit and include places where more point and line elements can work at the same time. Area elements are the most complex group of elements where at least one-line element (and even more) and at least two (and even more) point elements can be considered within the area element. For example, railway junctions, passageways with crossing safety equipment, railway stations with station safety and security devices and some traffic management systems will be primarily included in the group of the area elements.

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Elements of railway infrastructure can be further classified as critical and routine. Critical elements are characterized by their increased importance in the railway infrastructure network. Disruption or failure of these elements could have a significant negative impact on the lives and health of passengers or economic losses of the operator. Potential elements of critical infrastructure in rail transport include [4]: • dispatcher workplaces – technological complexes of traffic-transport management at all levels, • significant railway nodes, • international corridor tracks, • railway bridges and railway tunnels. 2.2

Threats to Rail Infrastructure

The elements of rail infrastructure are heavily influenced by the threats that affect them. These can be classified according to several aspects, such as threats inside the system and threats outside the system; or threats dependent or independent on human activities. The International Union of Railways (UIC) also monitors and evaluates major incidents in railway transport within the “UIC Security Database”. From the point of view of causal causes, they are divided into [13]: • infrastructure (rail, track, artificial constructions, security and safety equipment, etc.); • vehicles (traction, towed etc.); • human factor (employees by occupation, contractors); • users (passengers, carriers); • weather (mist, flood, frost) and environment (animals, fallen tree, hail, etc.); • third persons (entrance to the track, equipages crossings railways); • not identified. The most significant threats to bridges include large-scale floods, extreme weather fluctuations, landslides, large-scale crashes from the external environment, disruption of large waterworks and large-scale violation of legality, such as a bomb attack [11]. 2.3

Identification of Critical Infrastructure Elements

In 2014 researchers focused on Quantification of impacts on transport serviceability at the loss of functionality of significant infrastructure objects [8]. In the following years, the research was further focused on various methodologies for identifying critical infrastructure (CI) elements, mainly the German methodology SECMAN [16] and the Czech methodology CritInfo [17] appeared to be appropriate. The criteria were primarily focused on assessing the performance of the transport infrastructure and determining its impact in case of failure. The German approach SECMAN is mainly focused on road infrastructure to define precise criteria for assessing the structural characteristics of the most important infrastructure elements (tunnels and bridges in the methodology). For these types of objects, the qualitative criteria that define the bridges and tunnels type objects are defined, and a specific vulnerability value is calculated for each type of object.

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Based on the analysis of these approaches, a general universal procedure for defining the group of potential critical infrastructure elements in the railway transport sub-sector has been proposed and successfully verified [5]. The proposed procedure consists of several follow-up steps: • definition and method of evaluation of basic attributes of line elements – infrastructure stretches – in the area of interest, • identification of significant stretches and determination of the so-called importance index of the stretch (selection of the most important stretches), • definition and method of evaluation of basic typological objects in the stretch, • identification of significant objects and determination of the so-called importance index of the object which results from the determination of the value of the socalled general index of object importance and the determination of the so-called specific index of the object (selection of the most important objects), • and consequently the determination of the so-called total criticality index. In the following years, the issue of critical elements of the railway infrastructure was given considerable attention also in the Czech Republic and Slovakia. In the Czech Republic, particular attention was paid to an integrated approach to assessing the criticality of railway infrastructure elements [14], while in Slovakia attention was paid to the identification of individual critical objects [10].

3 Criterion-Based Assessment of Railway Bridges Criticality Based on the background material on the issue e.g. [9], and on the basis of consultations with employees dealing with critical infrastructure protection issues (at the level of the Ministry of Transport and Construction of the Slovak Republic, knowledge gained from the Slovak Railway Company employees as a railway infrastructure operator) new sectoral criteria for objects that are considered as the most vulnerable were defined. These objects are bridge objects, tunnel objects and railway stations. Only proposals of criteria for railway bridges are presented in the paper. 3.1

Methodology for Assessment of Railway Bridges Criticality

The assessment methodology is based on well-known procedures based on the use of risk assessment methodologies and good practice in identifying threats and risk assessment. The task within the methodology is to divide all expected tasks into specific processes with the determination of their owner, the beginning and the end, or their follow-up [2]. On the basis of the agreement of the experts was included a total of 12 criteria were defined for the resilience assessment which evaluate the individual bridges from technical and economic aspects. In addition, coefficients of individual criteria have been proposed, which have been tested in cooperation with railway transport experts. Based on the years of experience of the authors and in accordance with expert advice, a two or five-step assessment scale has been established. For single criterion, depending on the possible availability of the data, in nine cases was used five-step

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evaluation scale and, in the cases of the bridge pillar material, the number of tracks across the bridge structure and the part of trans-European corridors, was used only twostep scale. In the framework of the whole methodology, the final boundary values for determining critical elements were proposed, which were subsequently tested in cooperation with experts. The basic method was an interview focused on specifying boundary values. 3.2

Criteria for Bridge Objects

More than 50 years of research experience at technical protection and restoration has been used to define the criteria for bridges on the railway. Since the year 1965 the tasks focused on the optimization of the deployment of the forces and the means for the reconstruction of the railway lines have been solved at the former Military Faculty (nowadays Faculty of Security Engineering). In conditions of the railway army, new structures for the renewal of the railway bridges were developed. Within the military tests, the experts from the Faculty were continuously involved in testing and verification of newly designed structures. In the period before 1990, the Czechoslovak Railway Army rebuilt in an average more than 250 km of tracks per year, including bridges. Based on the above-mentioned experience of bridges, the research team set the following criteria (see Tables 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12): • • • • • • • • • • • •

Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion

1: Bridging Height, 2: Length of Bridge Object, 3: Load of Bridge Object, 4: Number of Pillars, 5: Material of Bridge Object, 6: Age of Bridge Object, 7: Access to Bridge Object, 8: Traffic Intensity on Bridge Object from View of Economy, 9: Traffic Intensity on Bridge Object - Number of passenger trains, 10: Economic Impact, 11: Number of Tracks on the Route Over Bridge, 12: Part of the Trans-European Corridors. Table 1. Criterion 1 – Bridging Height. Result Negligible (1) Small (2) Middle (3) Significant (4) Critical (5) The coefficient C = 1.5

Threshold values of bridging height to 3 m from 3.01–to 8 m from 8.01–to 20 m from 20.01–to 30 m more than 30.01 m for this criterion was chosen to be

Criticality Assessment of Railway Bridges Table 2. Criterion 2 – Length of Bridge Object. Result Threshold values of length of bridge object Negligible (1) to 25 m Small (2) from 25.01–to 50 m Middle (3) from 50.01–to 100 m Significant (4) from 100.01–to 220 m Critical (5) more than 220.01 m The coefficient for this criterion was chosen to be C = 1.5 Table 3. Criterion 3 – Load of Bridge Object. Result Threshold values of load of bridge object Negligible (1) to 200 tons Small (2) from 200 tons–to 1,000 tons Middle (3) from 1,000 tons–to 2,000 tons Significant (4) from 2,000 tons–to 3,000 tons Critical (5) more than 3,000 tons The coefficient for this criterion was chosen to be C = 1.1 Table 4. Criterion 4 – Number of Pillars. Result Negligible (1) Small (2) Middle (3) Significant (4) Critical (5) The coefficient C = 1.5

Threshold values of number of pillars max 0 2 4 6 8 and more for this criterion was chosen to be

Table 5. Criterion 5 – Material of Bridge Object. Result Threshold values of material of bridge object Low (2.5) Non - massive material High (5) Massive material The coefficient for this criterion was chosen to be C = 1.6 Table 6. Criterion 6 – Age of Bridge Object. Result Threshold values of age of bridge object Negligible (1) to 10 years Small (2) from 10–to 30 years Middle (3) from 30–to 70 years Significant (4) from 70–to 110 years Critical (5) above 110 years The coefficient for this criterion was chosen to be C = 1.2

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Z. Dvorak et al. Table 7. Criterion 7 – Access to Bridge Object. Result Threshold values of access to bridge object Negligible (1) Access to object without problems Small (2) Good access to object Middle (3) Access to object is difficult Significant (4) Access to object is complicated Critical (5) Access to object is very long and complicated The coefficient for this criterion was chosen to be C = 1.6 Table 8. Criterion 8 – Traffic Intensity on Bridge Object from View of Economy. Result Number of economic commodities transported in 24 h Negligible (1) to 1,000 t Small (2) from 1,000–to 2,500 t Middle (3) from 2,500–to 5,000 t Significant (4) from 5,000–to 7,500 t Critical (5) above 7,500 t The coefficient for this criterion was chosen to be C = 1.7

Table 9. Criterion 9 – Traffic Intensity on Bridge Object - Number of passenger trains. Result Number of persons transported in 24 h Negligible (1) to 5,000 persons Small (2) from 5,000–to 10,000 persons Middle (3) from 10,000–to 15,000 persons Significant (4) from 15,000–to 30,000 persons Critical (5) above 30,000 persons The coefficient for this criterion was chosen to be C = 1.7 Table 10. Criterion 10 – Economic Impact. Result Negligible (1) Small (2) Middle (3) Significant (4) Critical (5) The coefficient C = 1.5

Threshold values of economic impact to 5,000 € from 5,000–to 20,000 € from 20,000–to 100,000 € from 100,000–to 1,000,000 € above 1,000,000 € for this criterion was chosen to be

Table 11. Criterion 11 – Number of Tracks on the Route Over Bridge. Result Number of tracks Low (2.5) Single-track High (5) Multi-track The coefficient for this criterion was chosen to be C = 1.4

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Table 12. Criterion 12 – Part of Trans-European Corridors. Result Number of tracks No (2.5) Is not part of Trans-European Network Yes (5) Is part of Trans-European Network The coefficient for this criterion was chosen to be C = 1.6

The result value of the selected criteria: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion Criterion

1 can reach value 1.5–7.5; 2 can reach value 1.5–7.5; 3 can reach value 1.1–5.5; 4 can reach value 1.5–7.5; 5 can reach value 4.0–8.0; 6 can reach value 1.2–6.0; 7 can reach value 1.6–8.0; 8 can reach value 1.7–8.5; 9 can reach value 1.7–8.5; 10 can reach value 1.5–7.5; 11 can reach value 3.5–7.0; 12 can reach value 4.0–8.0.

The result value will range from a minimum of 24.8 to a maximum of 89.5 points. The sum of partial values of the individual criteria for assessment of bridge objects can reach a final value ranging from the minimum value of 24.8 points (which indicates that the bridge object has a bridging height of up to 3 m, a bridging length of up to 25 m, a load of up to 200 t, bridge material is not massive, the age of the bridge object is up to10 years, the access to the bridge object is without problems, etc., and from the point of view of critical infrastructure protection it is the least significant element) up to the maximum value of 89.5 points (which indicates that the bridge object has the height of the bridging over 30 m, bridging length over 220 m, load over 3,000 t, material of bridge object is massive, age of bridge over 110 years, access to bridge object is very long and complicated, etc. and from the point of view of critical infrastructure protection it is a critical element that should definitely be included in the group of critical infrastructure elements). The minimum value of 24.8 points represents the minimum risk of destroying the bridge object, the maximum value of 89.50 points represents the maximum risk of its destruction. The maximum possible value is 64.7 points, i.e. 100%. Based on the evaluation of the obtained results, we have determined that all bridge objects, the result value of which reaches 85% of the maximum value, representing 55.00 points and more, will be considered as critical objects to be included in the group of potential elements intended for protection of critical infrastructure. Research on critical infrastructure protection at the faculty is carried out in the framework of researched research projects, as well as in solved diploma and dissertation thesis. The solution to Martin Celko’s thesis started the discussion that it is

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necessary to amend them after 8 years from the creation of the original criteria for the inclusion of railway infrastructure objects. The entire process lasted more than a year and was involved in both the research and operational staff [3].

4 Conclusion The aim of the paper was to start a discussion on the new proposal of criteria for identifying critical objects in railway infrastructure. In the wide-ranging professional debate, a large number of experts have expressed the view that railway transport has a current irreplaceable place in transport services and in the national economy. The question who will implement the railway infrastructure renewal is given by the laws. The key issue is timeframe of railway transport renewal. This question has no definite answer at present. The issue of public procurement is decisive; the issues of used materials and technologies are secondary. Acknowledgements. Publication of this paper was supported by the Centre of excellence for systems and services of intelligent transport II., ITMS 26220120050 supported by the Research & Development Operational Programme funded by the ERDF and by the Ministry of the Interior of the Czech Republic, grant No. VI20152019049, entitled ‘Dynamic Resilience Evaluation of Interrelated Critical Infrastructure Subsystems’.

References 1. Aflatooni, M., Chan, T.H.T., Thambiratnam, D., Thilakarathna, H.M.I.: Classification of railway bridges based on criticality and vulnerability factors. In: Rowbottam, R. (ed.) Proceedings of the Australian Structural Engineers Conference, Engineers Australia, Perth, WA, pp. 1–8 (2012) 2. Bureika, G., Bekintis, G., Liudvinavičius, L., Vaičiūnas, G.: Applying analytic hierarchy process to assess traffic safety risk of railway infrastructure. Maint. Reliab. 15(4), 376–383 (2013). ISSN 1507-2711 3. Celko, M.: Design of relevant criteria for identifying the set of potential critical infrastructure elements in the rail transport sub-sector. Diploma thesis. University of Zilina. Faculty of Security Engineering (2018) 4. Dvorak, Z., Cizlak, M., Leitner, B., Sousek, R., Sventekova, E.: Risk Management in Rail Transport, Monography. 1st edn. Institute of Jan Perner, Pardubice (2010) 5. Dvorak, Z., Sventekova, E., Rehak, D., Cekerevac, Z.: Assessment of critical infrastructure elements in transport. Procedia Eng. 187, 548–555 (2017) 6. Hofreiter, L., Boc, K., Jangl, S., Lovecek, T., Mach, V., Seidl, M., Selinger, P., Velas, A.: Protection of critical transport infrastructure objects. Monograph, 1st edn. EDIS University of Zilina, Zilina (2013) 7. Leitner, B., Luskova, M., Titko, M.: Modelling of impacts of bridge functionality loss on transport serviceability. In: Transport Means 2017: Proceedings of the 21st International Scientific Conference: Juodkrante, Lithuania. Part I. Kaunas University of Technology, pp. 86–91 (2017)

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8. Leitner, B., Luskova, M., O’Connor, A., van Gelder, P.: Quantification of impacts on the transport serviceability at the loss of functionality of significant road infrastructure objects In: Communications - Scientific Letters of the University of Zilina, Slovakia, vol. 17, no. 1, pp. 52–60. University of Zilina (2015) 9. Leitner, B., Mocova, L., Hromada, M.: A new approach to identification of critical elements in railway infrastructure. Procedia Eng. 187, 143–149 (2017) 10. Leitner, B., Rehak, D., Kersys, R.: The new procedure for identification of infrastructure elements significance in sub-sector railway transport. Communications 20(2), 41–48 (2018) 11. Ministry of the Interior of the Czech Republic: Threat Analysis for the Czech Republic: Final Report. 2015. Approved by Resolution of the Government of the Czech Republic of 27 April 2016, no. 369, 9 pp. (2015) 12. Rehak, D., Senovsky, P., Hromada, M., Lovecek, T.: Complex approach to assessing resilience of critical infrastructure elements. Int. J. Crit. Infrastruct. Prot. 25, 125–138 (2019) 13. Sterba, R.: UIC and EU Security Statistics. Scientific and Technical Proceedings ČD, č. 40/2015, Czech Railways, Ltd., 7 p. (2015) 14. Slivkova, S., Rehak, D., Novotny, P.: Critical element designation system in rail transport in the Czech Republic. Chem. Eng. Trans. 67, 775–780 (2018) 15. Zhang, Z., Li, X., Li, H.: A quantitative approach for assessing the critical nodal and linear elements of a railway infrastructure. Int. J. Crit. Infrastruct. Prot. 8, 3–15 (2015) 16. Methodic SecMan (2019). http://www.studiomars.si/secman/docs/P28833_Handbuch_ Secman_GB.pdf 17. Methodic CritInfo (2019). http://www.cztpis.cz/files/2011/02/Risk_Assessment_Transport_ Infrastructure.pdf

Energy and Ecological CI Engine Indicators Having Replaced Diesel with Chicken Fat Alfredas Rimkus1,2(&), Tadas Vipartas2, Jonas Matijošius1,2, Saulius Stravinskas1,2, and Oleksandra Shepel1 1

Vilnius Gediminas Technical University, J. Basanavičius str. 28, 03224 Vilnius, Lithuania {alfredas.rimkus,jonas.matijosius, saulius.stravinskas,oleksandra.shepel}@vgtu.lt 2 Vilnius College of Technologies and Design, Antakalnio str. 54, 10303 Vilnius, Lithuania [email protected]

Abstract. Diesel-powered compression ignition (CI) engines use fossil fuels, which results in increasing greenhouse gas emissions and environmental pollution. Chicken fat, which is attributed to renewable fuels, is one of possible alternatives to diesel. This Article presents an experimental comparative research at various speeds (from 60 km/h to 90 km/h), replacing diesel with chicken fat at 30%, 50%, 70% and 100%. Cold chicken fat is highly viscous, so fuel was heated. Measurements of volumetric fuel consumption and the analysis of pollutant (CO2, HC, NOx and smoke) concentration in engine exhausts were performed revealing that fuel consumption increases with increasing chicken fat concentration in fuel, and the Brake Thermal Efficiency of the engine decreases. CO2 concentration increases, but HC and NOx concentration and smoke decrease. This is due to a change in the combustion process and the chemical composition of fuel having replaced diesel with chicken fat. Keywords: Fuel consumption Diesel
Chicken fat


Pollutants
Compression ignition engine


1 Introduction Currently, the world is facing two critical issues, namely, increased environmental degradation and depletion of fossil fuels. Nowadays, the transport industry is of great importance to social and economic development of all countries of the world, at the same time being the main source of harmful emissions [1]. From international perspective, the major global concern is the promotion of ecofriendly alternative fuels. The use of biodiesel has shown a positive impact on resolving these issues [2–9]. In this respect, biodiesel is non-toxic, biodegradable fuel free of aromatics and dioxins; its high flash point makes it safer for storage and transportation [3, 9]. Moreover, its ability to burn in standard internal combustion engines because of its properties that are similar to those of diesel is yet another advantage of biodiesel [10]. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 484–493, 2020. https://doi.org/10.1007/978-3-030-38666-5_51

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Many scientists have found [3, 5, 8] that waste chicken fat is a very attractive raw material for biodiesel production because of its cost being much lower than the cost of vegetable oil [11] and because of its low pollutant content like sulphur, hydrocarbons, soot, particulate matter or hazardous metals. A review of the most important research in the field of the use of biofuels of chicken origin to power CI engines presented on the basis of the results of the experimental research shows the impact of chicken fat on auto ignition delay, combustion parameters, such as the maximum pressure rise rate, cylinder peak pressure, combustion duration, exhaust temperature, heat release rate characteristics and exhaust gas emissions. In the first research [12], experiments were carried out with various blends of chicken fat-based biodiesel. Biodiesel was used in a blend with diesel and chicken fat at concentrations of 10%, 20%, 30%, 40% and 50%. The experiments were carried out at the constant engine speed of 2,800 rpm for different loads. The research revealed that out of all chicken fat biodiesel mixtures, the 30% mixture concentration only was similar to diesel in terms of performance and emission parameters. Emission indicators, such as carbon dioxide (CO2), nitrogen dioxide (NO2) and hydrocarbon (HC) emissions, were found to increase with increasing percentage concentration of chicken fat in fuel blends. Another scientific publication [3] studied the performance, combustion and pollutant emissions of biodiesel from animal fat residues (AFR). Tests were performed on a single cylinder with direct injection diesel engine at 1,500 rpm. The use of AFR in the engine showed a reduction with brake thermal efficiency at low loads and a slight increase at high loads. Also, the use of AFR led to a 9% power drop because of its lower heating value. When it comes to pollutant emissions, a reduction in HC at all loads was observed. PM emissions were also reduced at low loads, and they were noticed to disappear altogether at high loads. Complete fuel combustion is known to lead to the generation of lower PM emissions due to higher oxygen content in biodiesel. As for NOx emissions, they increased at low loads by 20% and decreased by 4% at full load. Alptekin [2] used waste chicken fat in different proportions mixed with diesel. Fuel blends were tested on a 6-cylinder engine. The test revealed that when the engine was fuelled on biodiesel mixtures, the start of combustion occurred earlier. In addition, brake specific fuel consumption (BSFC) was by an average of about 16% higher compared to diesel. Lower CO emissions were observed when using biofuel, but CO2 and NO2 emissions were higher. Other authors [9] analysed the effect of emissions from biodiesel made of edible and non-edible vegetable oil, chicken fats and waste oil in CI engine. The engine was operated on different loads – 25%, 50%, 75% and 100%, with constant engine speed of 1,500 rpm. Their experimental work revealed that NOx emissions are lower at all loads for all kind of biodiesel compared to diesel. The biodiesel NOx effect can be mitigated by modifying engine control settings – particularly by retarding injection timing and increasing exhaust gas recirculation [13]. In order to exploit the available firstgeneration biofuel production resources and to smoothly move to new biofuel production technologies, using diesel and biodiesel blends in line with the LST EN 590:2014 standard requirements would be rational. Table 1 presents key properties of diesel and biodiesel.

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Indicator

RRME (biodiesel) Diesel

Density, g/ml 0.85–0.90 Sulphur content, ppm 0–0.012 Cetane number, 45–73 Lower calorific value, MJ/kg 37.1–40,4 Flash point, °C 96–188 Water content, mg/kg 28.5–500 Viscosity 40°C, cSt 3.89–7.9

0.85 12 50 34.97 52–136 0.5 2.71

LST EN 590 standard Chicken fat [14] 0.8/0.845 –/10 51/– 35/– 60/170 –/200 2/4.5

0.870 – 58.4 39.3 174 0.12 (% mass) 5.4

The aim of the study was to determine the trends of changes in the energy and ecological indicators of the compression ignition engine by replacing diesel with pure chicken fat (not chicken fat-based biodiesel) and its mixtures with diesel. The main aim of this article is to test CI engine ecological indicators by change traditional diesel fuel to the it mixture with various amount of chicken fat. The objectives were formatted to reach the main aim and were are: 1. To analyse what ecological parameters according another authors are necessary to do if there were changed a diesel fuel to diesel fuel – chicken fat fuel mixture. 2. To analyse the change of the CI engine’s ecological indicators, when there are fuelled diesel fuel – chicken fat fuel mixture.

2 Research Diesel Fuel – Chicken Fat Fuel Mixture Methodology The experimental research was carried out on Volkswagen Golf III, the main technical data of the compression ignition engine of which are presented in Table 2. Fuel consumption was measured using a fuel consumption meter AIC-1204 HD 2000. Table 2. Parameters of tested engine VW 1.9 TDI (1Z type). Parameter Value 3 1,896 Displacement, cm Number of cylinders 4 Compression ratio 19.5 Power, kW 66 (4,000 rpm) Torque, N m 202 (1,900 rpm) Bore, mm 79.5 Stroke, mm 95.5 Number of valves in a cylinder 4 Cooling system Liquid

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Fig. 1. Measuring fuel consumption: 1 – internal combustion engine; 2 – fuel capacity with heating elements; 3 – fuel filter; 4 – fuel consumption meter AIC-1204 HD 2000; 5 – high pressure fuel pump; 6 – electronic engine control unit; 7 – PC.

The fuel meter was additionally mounted in the car power supply system (Fig. 1). Key technical data of the device are presented in Table 3. A fuel filter and a fuel tank with a heating element was installed ahead of the fuel consumption meter. Experimental research was carried out using a computerized car test traction stand CARTEC LPS 2510. The traction test stand allows testing cars at any gear with the selected load or the calculated driving resistance. The eddy-current electromagnetic brake, which converts the mechanical engine power transmitted to the wheels into thermal energy and radiates it into the environment, creates the vehicle load. The key technical data of the traction stand are presented in Table 4.

Table 3. Fuel consumption meter data.

Table 4. Technical car traction stand data.

Parameter

Device Fuel consumption meter AIC-1204 HD 2000

Parameter

Device Car traction stand CARTEC LPS 2510

Measurement limits, l/h Max. engine power, kW Accuracy, % Repeatability, % Permissible pressure, bar Working temperature, °C Voltage, VDC

4 to 200

Load device Maximum load, t Maximum stand measurement power, kW Maximum stand braking power, kW Measurement error

Eddy-current 3.5 400

515 >1 >0.2 −1 to 20

360 ±2

−30 to 90 8–28

The research was carried out with the engine running on pure diesel (marked as D100/F0 in graphs) and on pure chicken fat (marked as D0/F100 in charts). Also blends of diesel and grease obtained by mixing fuel at the following volume ratios were

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used: 70% diesel/30% chicken fat (D70/F30), 50% diesel/50% chicken fat (D50/F50), 30% diesel/70% chicken fat (D30/F70). At low temperatures, chicken fat fuels and their blends with diesel stratified and were too viscous (Fig. 2). In order to ensure appropriate viscosity of fuel mixtures, they were heated to *60 °C (Fig. 3) using the heating element (Fig. 1). When the engine was running on diesel, the fuel temperature was *40 °C. The composition of exhaust gases was determined using the gas analyser CARTEC CET 2200 C, the technical data of which are presented in Table 5.

Table 5. Technical data of the gas analyser CARTEC CET 2200 C.

Fig. 2. Containers with diesel and chicken fat mixtures of different concentration.

Parameter Description Limits of measurement

Scale error

CO CO2 CH NOx O2 Smoke K

0.01% vol. 0.1% vol. 1 ppm 5 ppm 0.01% vol. 0.01

0–9.99% vol. 0–19.9% vol. 0–9,999 ppm vol. 0–2,000 ppm vol. 0–25% vol. 0–9.99 m−1

Fuel consumption was measured at a fixed wheel load (F = 500 N) at the vehicle speed v (60 km/h, 70 km/h, 80 km/h, 90 km/h) with engaged fourth gear. During the tests, the engine brake power PB (kW), engine speed n (rpm) and hourly volumetric fuel consumption Bf_V (l/h) was measured, car fuel consumption per 100 km (l/100 km) was calculated. Fuel Lower Heating Value (LHV) indicator was set using the IKA C 5000 calorimeter. Diesel’s LHV was 42.5 MJ/kg and that of chicken fat – 39.77 MJ/kg (*6.4% lower). Lower calorific value of fuel mixtures was determined in application of the principle of additionality. Figure 4 presents its calculation results.

Fig. 3. Density of fuel mixtures.

Fig. 4. LHV of fuel mixtures.

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The density of pure diesel at the temperature of 15 °C was determined to be 839 kg/m3 and that of chicken fat – 908 kg/m3 (*8.2% higher) [14]. Using the fuel meter AIC, the temperature of diesel supplied to the engine increased to *40 °C due to the specifics of the fuel supply system, and its density dropped to 821 kg/m3 (Fig. 3). In order to avoid the clogging of the filter, fuel temperature was raised to *60 °C when using mixtures of diesel and chicken fat. The density of hot pure chicken fat decreased to 869.3 kg/m3. At 60 °C, the density of fuel mixtures D70/F30 (825 kg/m3) and D50/F50 (835 kg/m3) became similar to the density of diesel. Increasing chicken fat concentration proportionately increased the density of the mixture.

3 Research Results and Their Analysis The measurements of fuel consumption revealed that the increase of the speed of a vehicle from 60 km/h to 90 km/h leads to an increase of hourly volume and mass consumption of all fuel mixtures (Fig. 5a, c). The load on the vehicle’s driving wheels was constant (F = 500 N), but the engine speed was increased from *1,600 rpm to *2,400 rpm, which increased the number of fuel injections per hour and hourly fuel consumption. Volumetric fuel consumption per 100 km changed slightly (Fig. 5c), but the vehicle’s hourly driving distance (km/h) increased in proportion to increasing engine speed. During the test, increasing mechanical losses in the engine slightly increased fuel consumption with increasing engine speed [15, 16]. The comparison of consumption of different types of fuel revealed that when increasing the concentration of chicken fat in the mixture from 0% to 30%, 50%, 70% and 100%, hourly volumetric consumption increased by *2.5%, *4.1%, *5.0% and *7.1% (Fig. 5a). When increasing the chicken fat concentration, volumetric fuel consumption per 100 km grew by *2.3%, *3.7%, *4.9% and *7.0% (Fig. 5c). The increase of the chicken fat concentration to 100% led to the decline of the fuel mixture LHV by *6.4%, which was the main reason for increased fuel consumption. Hourly fuel mass consumption increased by *3.0%, *4.8%, *8.3% and *13.6%. In addition to the fuel LHV decreased by *6.4%, this was also determined by fuel density increased by *5.9% having increased chicken fat concentration to 100%. With the engine running on all fuel mixtures, the increase of the vehicle speed from 60 km/h to 90 km/h led to decreased carbon dioxide (CO2 – greenhouse gas) concentration in exhaust gases (Fig. 6a), because increasing engine speed from *1,600 rpm to *2,400 rpm increased the air inflow pressure. During the experimental research, the load on the vehicle’s driving wheels was constant (F = 500 N), so that the amount of fuel injected during the cycle did not change significantly and the concentration of combustion products in the exhaust gas decreased as the cylinder was filled with air. When increasing the chicken fat concentration in the fuel mixture from 0% to 30%, 50%, 70% and 100%, the CO2 concentration in the entire tested speed range increased by *0.4%, *1.2%, *2.4% and *3.2%. The main reason for the increase in CO2 concentration was increased hourly fuel mass consumption (*3.0%, *4.8%, *8.3% and *13.6%) (Fig. 5c). Oxygen contained in chicken fat, which regulates carbon oxidation, also increases CO2 concentration [17, 18].

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Fig. 5. Energy engine indicators with the vehicle running on different fuel at different speeds: (a) hourly volumetric fuel consumption; (b) volumetric fuel consumption per 100 km; (c) hourly fuel mass consumption; (d) Brake Thermal Efficiency of the engine.

Fig. 6. Ecological engine indicators with the car running on different fuels at different speeds: (a) carbon dioxide; (b) hydrocarbons; (c) nitrogen oxides; (d) smoke.

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Increasing the fat concentration in the fuel mixture up to 70%, the concentration of unburnt hydrocarbons (HC) in the exhaust gas grew to *9.9%, but using D0/F100 fuel, it decreased by *31.1% (Fig. 6b). The 100% chicken fat fuel reduced the HC concentration due to a simpler fuel molecular chain and oxygen contained in fuel. Concentrations of nitrogen oxides (NOx) in the exhaust gas were reduced by increasing the speed of cylinders due to better cylinder filling and low cyclic fuel consumption. Increasing the chicken fat concentration in the fuel mixture from 0% to 30%, 50%, 70% and 100%, the NOx concentration in the entire tested speed range decreased by *12.9%, *6.9%, *7.1% and *13.8% (Fig. 6c). The NOx concentration decreased because chicken fat has a lower LHV, higher viscosity, cetane number and other physical-chemical properties. This reduces the intensity of heat release in the cylinder and the combustion temperature, which affects the formation of NOx [13]. Increasing the car speed, the concentration of nitrogen oxides (NOx) decreased in the exhaust gas due to a better cylinder filling with air and a minor change in the cyclic volume of fuel. Increasing the chicken fat concentration in the fuel mixture from 0% to 30%, 50%, 70% and 100%, NOx concentration decreased by *12.9%, *6.9%, *7.1% and *13.8% in the entire tested speed range (Fig. 6c). Such decrease was due to the fact that chicken fat has a lower LHV, a higher viscosity, its cetane number and other physico-chemical properties are different, which reduces the intensity of heat release in the cylinder and the combustion temperature affecting the formation of NOx. Exhaust gas smoke has a tendency to decrease with increasing car speed, because increasing the engine speed from *1,600 rpm to *2,400 rpm, the air inflow pressure increased and the engine braking torque was constant, but the excess air coefficient increased. Increasing the chicken fat concentration in the fuel mixture from 0% to 30%, 50%, 70% and 100%, the exhaust gas smoke decreased in the entire range of tested speeds by *25%, *31%, *34% and *40% (Fig. 6c). The following were the main reasons having led to this drop in smoke: oxygen contained in chicken fat fuel improved carbon oxidation; molecular composition of chicken fat is simpler; lower C/H ratio; prolonged combustion process [19].

4 Conclusions Having measured gas consumption and composition of exhaust gases of a compression ignition engine running on pure diesel at the car speeds of 60 km/h, 70 km/h, 80 km/h and 90 km/h, and increasing the chicken fat concentration in the mixture from 0% to 30%, 50%, 70% and 100%, at the fixed load of driving wheels, the following generalized changes in the energy and ecological indicators of the engine and their reasons were identified: 1. In the tested vehicle speed range, hourly volumetric fuel consumption gradually increased to *7.1% and fuel mass consumption grew to *13.6% when increasing the chicken fat concentration in the mixture from 0% to 100%. This was mainly due to *6.4% lower chicken fat LHV and *5.9% higher density. 2. Having gradually replaced diesel with chicken fat, the engine’s BTE decreased to *5.9%, because the nature of fuel injection and combustion changed due to

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physico-chemical properties of fuel and the differences in cetane number. In order to achieve higher BTE, maintaining the appropriate fuel mixture temperature and optimizing the start and intensity of fuel injection is necessary. 3. Increasing the chicken fat concentration in the fuel mixture to 100%, CO2 concentration increased to *3.2%. An increase of hourly fuel mass consumption to *13.6% and increased oxygen concentration in fuel are the main reasons for increased CO2 concentration. However, chicken fat is a renewable fuel and, considering its life cycle, greenhouse gas emissions are likely to decrease. 4. The NOx concentration decreased to *13.8%, because chicken fat has a lower LHV, a higher viscosity, different cetane number and other physico-chemical properties. This reduced the intensity of heat release and the combustion temperature. 5. Gradually increasing the chicken fat concentration in the fuel mixture to 100%, exhaust gas smoke dropped to *40%, because chicken fat contains more oxygen, which improves hydrocarbon oxidation. Chicken fat has a simpler molecular composition, lower C/H ratio and delayed burning process due to a longer lasting injection.

References 1. Othman, M.F., Adam, A., Najafi, G., Mamat, R.: Green fuel as alternative fuel for diesel engine: a review. Renew. Sustain. Energy Rev. 80, 694–709 (2017) 2. Alptekin, E., Canakci, M., Ozsezen, A.N., Turkcan, A., Sanli, H.: Using waste animal fat based biodiesels–bioethanol–diesel fuel blends in a DI diesel engine. Fuel 157, 245–254 (2015) 3. Awad, S., Loubar, K., Tazerout, M.: Experimental investigation on the combustion, performance and pollutant emissions of biodiesel from animal fat residues on a direct injection diesel engine. Energy 69, 826–836 (2014) 4. Armas, O., Gómez, A., Ramos, Á.: Comparative study of pollutant emissions from engine starting with animal fat biodiesel and GTL fuels. Fuel 113, 560–570 (2013) 5. Banković-Ilić, I.B., Stojković, I.J., Stamenković, O.S., Veljkovic, V.B., Hung, Y.-T.: Waste animal fats as feedstocks for biodiesel production. Renew. Sustain. Energy Rev. 32, 238– 254 (2014) 6. Behçet, R.: Evaluation as fuel diesel engine of methyl esters derived from waste animal fats. Energy Explor. Exploit. 33, 227–242 (2015) 7. Duda, K., Wierzbicki, S., Śmieja, M., Mikulski, M.: Comparison of performance and emissions of a CRDI diesel engine fuelled with biodiesel of different origin. Fuel 212, 202– 222 (2018) 8. Gandure, J., Ketlogetswe, C., Jonas, M.: Production, composition and fuel properties of tallow biodiesel: a case of Botswana. Energy Power Eng. 09, 355–365 (2017) 9. Rajak, U., Verma, T.N.: Effect of emission from ethylic biodiesel of edible and non-edible vegetable oil, animal fats, waste oil and alcohol in CI engine. Energy Convers. Manag. 166, 704–718 (2018) 10. Huang, L., Bohac, S.V., Chernyak, S.M., Batterman, S.A.: Effects of fuels, engine load and exhaust after-treatment on diesel engine SVOC emissions and development of SVOC profiles for receptor modeling. Atmos. Environ. 102, 228–238 (2015)

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11. Chakraborty, R., Gupta, A.K., Chowdhury, R.: Conversion of slaughterhouse and poultry farm animal fats and wastes to biodiesel: parametric sensitivity and fuel quality assessment. Renew. Sustain. Energy Rev. 29, 120–134 (2014) 12. Shahir, V.K., Jawahar, C.P., Suresh, P.R., Vinod, V.: Experimental investigation on performance and emission characteristics of a common rail direct InjectionEngine using animal fat biodiesel blends. Energy Procedia 117, 283–290 (2017) 13. Hoekman, S.K., Robbins, C.: Review of the effects of biodiesel on NOx emissions. Fuel Process. Technol. 96, 237–249 (2012) 14. Mata, T.M., Cardoso, N., Ornelas, M., Neves, S., Caetano, N.S.: Evaluation of two purification methods of biodiesel from beef tallow, pork lard, and chicken fat. Energy Fuels 25, 4756–4762 (2011) 15. Heywood, J.B.: Internal Combustion Engine Fundamentals. McGraw-Hill, New York (1988) 16. Singh, D., Subramanian, K.A., Singal, S.K.: Emissions and fuel consumption characteristics of a heavy duty diesel engine fueled with Hydroprocessed Renewable Diesel and Biodiesel. Appl. Energy 155, 440–446 (2015) 17. Chauhan, B.S., Singh, R.K., Cho, H.M., Lim, H.C.: Practice of diesel fuel blends using alternative fuels: a review. Renew. Sustain. Energy Rev. 59, 1358–1368 (2016) 18. Guan, C., Cheung, C.S., Li, X., Huang, Z.: Effects of oxygenated fuels on the particle-phase compounds emitted from a diesel engine. Atmos. Pollut. Res. 8, 209–220 (2017) 19. Asokan, M.A., Senthur prabu, S., Kamesh, S., Khan, W.: Performance, combustion and emission characteristics of diesel engine fuelled with papaya and watermelon seed oil biodiesel/diesel blends. Energy 145, 238–245 (2018)

Improvement of Fuel Economy and Starting Properties of the Diesel Engine by Heating the Air at the Inlet Mykola Dmytrychenko1, Yurii Gutarevych2, Yevhenii Shuba2, Oleksandr Syrota2, Dmitrij Trifonov2, and Jonas Matijošius3(&) 1 Faculty of Automotive and Mechanical Engineering, Department of Manufacturing, Repair and Materials Engineering, National Transport University, Mykhaila Omelianovycha-Pavlenka Str. 1, Kyiv 01010, Ukraine [email protected] 2 Faculty of Automotive and Mechanical Engineering, Department of Engines and Thermal Engineering, National Transport University, Mykhaila Omelianovycha-Pavlenka Str. 1, Kyiv 01010, Ukraine [email protected], [email protected], {shuba90,voin1}@i.ua 3 Vilnius Gediminas Technical University, J. Basanavičius str. 28, 03224 Vilnius, Lithuania [email protected]

Abstract. The article presents the results of studies to facilitate the starting and reduce the duration of the warm-up of automotive internal combustion engines in conditions of low ambient temperatures. The factors affecting the start of a diesel engine are considered. It was noted that in order to improve the starting quality and reduce the warm-up time of a diesel engine at low ambient temperatures, it is advisable to use a thermal accumulator of the phase transition for heating the intake air. In order to determine the influence of the air intake temperature at the time of cranking the engine until the start of the diesel engine, fuel efficiency and emission of harmful substances in exhaust gases during warming up in idle mode, experimental studies of the 1.9TDI ASV diesel engine produced by Volkswagen AG were conducted. Keywords: Fuel consumption Diesel
Starting properties


Pollutants
Compression ignition engine


1 Introduction One of the priority directions of development of all sectors of the global economy is the creation of energy efficient technologies that allow rational use of energy resources. This fully applies to road transport [1]. Problems associated with the starting and warming up the internal combustion engines of vehicles are among the most complex, which occur during operation of motor vehicles in conditions of low ambient temperatures. Complications of the engine start-up are objective and are explained by the complexity of creating the crankshaft © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 494–503, 2020. https://doi.org/10.1007/978-3-030-38666-5_52

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starting speed, the deterioration of the conditions of mixture formation and combustion of the air-fuel mixture, and the fuel is deteriorating in economic and environmental indicators [2, 3]. High-quality formation of the air-fuel mixture in conditions of low ambient air temperatures largely determines the completeness of fuel combustion and, in general, the economic operation of the engine. The quality of the air-fuel mixture depends on the design of the engine’s power supply system, operational modes of operation, as well as the physicochemical properties of fuels and lubricants. The evaporation of fuel is characterized by the speed of its transition from the liquid phase to the gaseous and is the most important indicator that determines the processes of mixing and combustion of fuel and air mixture in the ICE [4]. The starting efficiency and subsequent warm-up of a cold diesel engine is influenced by natural and climatic factors, the level of adaptation of the vehicle to lowtemperature operating conditions, fuel and lubricants, and so on. Starting qualities of automobile diesel engines are estimated by the maximum temperature of reliable starting and the time required to prepare the diesel engine for load taking. With a decrease in the temperature of the engine and the ambient air, the reliability of the start can be significantly reduced, and the preparation time for taking the load will increase. Starting a cold engine requires additional equipment, complicates and increases the cost of the power plant, performs additional work during maintenance, and the start-up is accompanied by reduced engine life, increased fuel losses for non-production costs, increased emissions of harmful substances with exhaust gases [5]. Limiting temperature of reliable start depends on starting speeds - frequency of scrolling of crankshaft. This frequency in the cold diesel decreases, as the resistance of the crankshaft scroll increases, and the capacity of the rechargeable battery decreases. The low air temperature in the cylinder at the end of the compression trick results in a problem with self-ignition of the fuel and air mixture. Injection of fuel at low ambient temperatures adversely affect its spraying, heating and slows the evaporation of fuel, making it difficult to start the engine. Most of the fuel at the start of a cold engine condenses on the cold surfaces of the cylinder-piston group, which leads to the flushing of the oil film from the walls of the cylinder liner [6]. In connection with the above, the development and implementation of measures and devices to improve the energy efficiency of the internal combustion engine is relevant, which will allow to solve quite acute problems associated with the start and warm up of a cold diesel engine in low ambient temperatures [7–10]. To improve the quality of spray, the completeness and rate of evaporation of the fuel is possible by increasing the temperature of the air entering the engine. Increasing and stabilizing the intake air temperature in conditions of low ambient temperatures can provide the necessary quality and stable composition of the air-fuel mixture, which will lead to an improvement in fuel efficiency and a reduction in the emission of harmful substances in the exhaust gases of the internal combustion engine [11, 12]. The problem of starting the diesels of mobile machines in conditions of low ambient temperatures is widely known and deeply studied [13–18]. In spite of this, the technical means for facilitating the starting of a diesel engine are far from perfect and have a number of significant disadvantages [19–21].

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One of the main drawbacks of the existing intake air heating systems is that they use electrical energy or energy derived from burning fuel to obtain heat, which negatively affects the engine’s fuel efficiency. This study suggested the use of an inlet air heating system that uses the heat of exhaust gases as a source of heat. The exhaust heat generated during engine operation is accumulated in a phase transition heat accumulator and is used to preheat the intake air.

2 The Methodology of the Experiment The purpose of the experimental studies is to determine the effect of heating the air at the inlet on the fuel economy and environmental performance of a diesel car when it starts and is heated in low ambient temperatures. The object of experimental research is a modern diesel ASV 1.9 Tdi by Volkswagen AG with a computer engine management system, with an axial fuel pump of distribution type, equipped with an adjustable gas turbine turbo-compressor Garrett brand model GT 1749 V. To determine the efficiency of different methods of heating in low ambient temperatures, the engine is equipped with an inlet air heating system with a phase transition heat accumulator (PTHA) (Fig. 1).

Fig. 1. Diagram of the functioning of the intake air heating system with PTHA: 1, 2 – shut-off valves; 3 – device for automatic control of inlet air temperature (three-way valve).

A heat accumulator allows to accumulate and store part of the thermal energy of the exhaust gases, further ensuring the optimum temperature of the air on the inlet entering the engine from the environment. Modes of operation of the inlet air heating system with PTHA: operating mode of the engine with the normal system of intake of air (a–b) and exhaust of exhaust gases (j–e) – crane 2 open, cranes 1, 3 closed; PTHA charging mode – air (a–b), exhaust gases (j–g–d–e), crane 1 open, crane 2 closed (exhaust gases during operation of the engine pass through PTHA); modes of start and warming of the cold engine – air (z–v–b), exhaust gases (j–e), valve 1 closed, valve 2 open (cold air from the environment – through the PTHA enters the intake manifold of the engine).

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Charging PTHA to ensure the temperature of the heat exchanger about 100 °C was carried out before testing. The research of the effect of inlet air heating on the performance indicators of a diesel engine for a Volkswagen AG ASV 1.9 Tdi car was carried out at the KS-56 electrical brake boom in the engine test laboratory of the Engines and Heat Engineering Department of the National Transport University (Fig. 2). The purpose of the experimental studies is to determine the effect of heating the air at the inlet on the fuel economy and environmental performance of a diesel car when it starts and is heated in low ambient temperatures. The object of experimental research is a modern diesel ASV 1.9 Tdi by Volkswagen AG with a computer engine management system, with an axial fuel pump of distribution type, equipped with an adjustable gas turbine turbo-compressor Garrett brand model GT 1749 V. Continuous recording of rotational speed, diesel fuel flow, volume of fuel consumption, fuel temperature, coolant temperature, air temperature, was made by connecting a personal computer to the engine management system via the OBD-II diagnostic connector using a KL adapter. The connection of the laptop with the engine management system was provided by the diagnostic program VCDS 1.1. For further analysis and processing of results the diesel parameters were recorded during the start period using digital cameras. The air temperature in the inlet manifold and the oil in the engine crank were measured by a portable electronic thermometer WSD 10 with a remote sensor. The temperature of the exhaust gases at the inlet and outlet of the heat accumulator (charging circuit) was determined by primary thermoelectric thermal converters and a device for measuring and controlling the temperature of UKT38 SCH4. The smoke of the exhaust gases was estimated by the magnitude of the decrease in the light flux and the natural light-loss factor, measured by a portable smoke meter of the META-01MP type, whose photometric base is 0.43 m. The principle of operation of the device is based on the method of illumination of exhaust gases.

Fig. 2. Volkswagen AG ASV 1.9 Tdi on a brake stand with a phase transition heat accumulator.

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Measurement of the concentrations of carbon monoxide CO, the total hydrocarbons CnHn (on hexane C6H14) and NOx nitrogen oxides in BГ diesel during start-up and during warming were carried out with Bosch BEA060 V1.14 6E795EEC/AMM D6 F54B diagnostic gas analyzer. The start and warm up of the engine were carried out at an ambient temperature of −5 °C and the initial temperature of the oil in the lubrication system of about 0 °C. The end of the heating was determined by the achievement of the temperature of the oil in the engine lubrication system at 50 °C.

3 Research Results and Their Analysis To determine the effect of air heating on the inlet at the time of starting the engine at low ambient temperatures recorded the change in the frequency of rotation of the crankshaft and the time that will pass from the moment the starter is switched on until the moment of stable self-ignition fuel and a significant increase in the speed of the engine shaft (Fig. 3). During the start of the engine, a video was recorded of changes in the engine speed displayed on the digital tachometer screen.

Fig. 3. Effect of heating the air inlet on starting diesel VW 1.9TDI ASV using PTHA.

As can be seen from Fig. 3, when the air is heated at the inlet, the engine start time is reduced. In particular, the duration of the start of a diesel engine without heating the air at the inlet is 5 s, with heating – 3 s, which increases the reliability of the start of an unheated engine in low ambient temperatures. Engine warm-up was performed in idle mode with a crankshaft rotational speed of 903 rpm. The minimum idling speed in the VW 1.9TDI ASV engine is automatically set to the electronic control unit after the temperature of the cooling fluid reaches 8 °C. For the engine without air on the inlet, this temperature was reached in 86 s, with heating – after 65 s.

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The research results are shown in Fig. 4.

Fig. 4. The change in the performance of the engine VW 1.9TDI ASV from the warm-up time at idle using PTHA.

As can be seen from Fig. 4, the warm-up time of the engine with the heating of the air at the inlet is reduced by 7.7% from 910 s without heating the air to 840 s with the heating of the air at the inlet. Fuel consumption for the period of heating without heating the air at the inlet is 160 g, with the heating of air at the inlet – 140.5 g. Fuel economy in the process of warming is 12.2%. When using the PTHA, the air temperature at the start was maintained at 45–48 °C, which contributes to more intense engine warming. The temperature of the inlet without heating was 2 °C. From the figure it is clear that when the air is heated at the inlet, the temperature of the cooling fluid, starting with the third minute of the warming, rises more intensively. At the same time, the temperature of the exhaust gases increases. For the work of the diesel engine with the heating of the air at the inlet, the temperature of the exhaust gases from the second minute of the heating is higher on average by 18 °C than for the work without heating.

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The results of researches of the effect heating the inlet air to the environmental performance of diesel in heating mode shown in Fig. 5. As starting from the second minute warm-up engine operation parameters are stabilized, and the concentration of harmful substances in the exhaust gases do not change the environmental performance are shown only for the first 195 s of heating. However, taking into account that the engine was heated at idle, the attenuation coefficient of the luminous flux N ranged from 0 to 2%, which makes it impossible to determine the effect of intake air heating on the smokiness of engine exhaust gases for operation in this mode.

Fig. 5. Effect of heating the air inlet on the composition of the exhaust gases of the engine VW 1.9 TDI ASV while warming up at idle using PTHA.

As can be seen from the figure, when the air is heated at the inlet, the concentrations of incomplete combustion products CO and CmHn are reduced and CO2 concentrations increase, which indicates a more complete combustion compared to the engine without heating. In particular, concentrations of CO are reduced by 72% at the beginning of the heating and by an average of 24% from the second warming minute. Concentrations of CmHn decrease by an average of 47%. As the amount of intake air decreases during

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heating, the fuel-air mixture is somewhat enriched, as evidenced by a decrease in the air-a coefficient and a reduction in the oxygen concentration of O2 in the exhaust gases. Due to the temperature rise in the engine cylinder when the air is heated at the inlet, the concentration of NOx oxides increases. With the use of measured values of concentrations of harmful substances and hourly fuel and air consumption, mass emissions of harmful substances are calculated. The obtained data allow to objectively estimate the influence of air heating on entering the ecological parameters of a diesel engine in the modes of start-up and warm-up.

Fig. 6. Effect of the intake air heating in mass emissions of harmful substances from exhaust gases VW 1.9 TDI ASV engine during warm-up idling using PTHA.

As can be seen from Fig. 6, the heating of air at the inlet leads to a decrease in mass emissions of incomplete combustion products. In particular, mass emissions of CO are reduced by an average of 50%. The mass emissions of CmHn decrease by an average of 60%. By reducing fuel consumption, massive CO2 emissions also reduce. The mass emissions of NOx increase by an average of 40%.

4 Conclusions As a result of the research, it was found that the heating of the air at the inlet at an ambient temperature of −5 °C contributes to a reduction in the duration of the start-up and heating of the diesel engine. When the air is warmed up at the inlet, the startup time of the unheated engine is reduced by 2 s (from 5 to 3 s). The warm-up time is reduced by 7.7%. In particular, the duration of engine warm-up without heating the air at the

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inlet is 910 s, with heating – 840 s. By reducing the duration of the heating process and improving the combustion process in the engine fuel consumption is reduced by 12.2% (from 160 to 140.5 g). The heating of the air at the inlet leads to a decrease in the CO concentration by 72% at the beginning of the warm-up and an average of 24% since the second minute warming-up. Concentrations of CmHn decrease by an average of 47%. However, due to the temperature rise in the engine cylinder, when the air is heated at the inlet, the nitrogen oxide NOx concentration increases. Reducing fuel consumption and concentrations of incomplete combustion products reduces their mass emissions from exhaust gases. In particular, mass emissions of CO are reduced by an average of 50%. The mass emissions of CmHn decrease by an average of 60%. When the engine is warming up in idle mode with heated intake air, CO2 concentrations are reduced. As the concentration of nitrogen oxides increases, then their mass emissions are increased. The mass emissions of NOx oxides increase by an average of 40%. To reduce their negative impact on the environment it is expedient to equip the engine with a system of neutralization of exhaust gases.

References 1. Bektaş, T., Ehmke, J.F., Psaraftis, H.N., Puchinger, J.: The role of operational research in green freight transportation. Eur. J. Oper. Res. 274, 807–823 (2018) 2. Burr, M., Gregory, C.: Vehicular exhausts. In: Encyclopedia of Environmental Health, pp. 645–653. Elsevier (2011) 3. Masera, K., Hossain, A.K.: Biofuels and thermal barrier: a review on compression ignition engine performance, combustion and exhaust gas emission. J. Energy Inst. 92, 783–801 (2018) 4. Aghbashlo, M., et al.: Improving exergetic and sustainability parameters of a DI diesel engine using polymer waste dissolved in biodiesel as a novel diesel additive. Energy Convers. Manag. 105, 328–337 (2015) 5. Ko, J., Son, J., Myung, C.-L., Park, S.: Comparative study on low ambient temperature regulated/unregulated emissions characteristics of idling light-duty diesel vehicles at cold start and hot restart. Fuel 233, 620–631 (2018) 6. Rimkus, A., Melaika, M., Matijošius, J., Mikaliūnas, Š., Pukalskas, S.: Investigation of combustion, performance and emission characteristics of spark ignition engine fuelled with buthanol – gasoline mixture and a hydrogen enriched air. Adv. Sci. Technol. Res. J. 10, 102– 108 (2016) 7. Rimkus, A., Melaika, M., Matijošius, J.: Efficient and ecological indicators of CI engine fuelled with different diesel and LPG mixtures. Procedia Eng. 187, 504–512 (2017) 8. Zoldy, M., Hollo, A., Thernesz, A.: Butanol as a Diesel Extender Option for Internal Combustion Engines (2010). https://doi.org/10.4271/2010-01-0481 9. Szabados, G., Bereczky, Á.: Experimental investigation of physicochemical properties of diesel, biodiesel and TBK-biodiesel fuels and combustion and emission analysis in CI internal combustion engine. Renew. Energy 121, 568–578 (2018) 10. Jedliński, M.: The position of green logistics in sustainable development of a smart green city. Procedia Soc. Behav. Sci. 151, 102–111 (2014) 11. Musthafa, M.M.: Development of performance and emission characteristics on coated diesel engine fuelled by biodiesel with cetane number enhancing additive. Energy 134, 234–239 (2017)

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12. Gumus, M.: Reducing cold-start emission from internal combustion engines by means of thermal energy storage system. Appl. Therm. Eng. 29, 652–660 (2009) 13. Zare, A., et al.: Diesel engine emissions with oxygenated fuels: a comparative study into cold-start and hot-start operation. J. Clean. Prod. 162, 997–1008 (2017) 14. Gao, J., Tian, G., Sorniotti, A., Karci, A.E., Di Palo, R.: Review of thermal management of catalytic converters to decrease engine emissions during cold start and warm up. Appl. Therm. Eng. 147, 177–187 (2019) 15. Zare, A., et al.: A comparative investigation into cold-start and hot-start operation of diesel engine performance with oxygenated fuels during transient and steady-state operation. Fuel 228, 390–404 (2018) 16. Lapuerta, M., Ramos, Á., Barba, J., Fernández-Rodríguez, D.: Cold- and warm-temperature emissions assessment of n-butanol blends in a Euro 6 vehicle. Appl. Energy 218, 173–183 (2018) 17. Douki, T., et al.: Comparative study of diesel and biodiesel exhausts on lung oxidative stress and genotoxicity in rats. Environ. Pollut. 235, 514–524 (2018) 18. Faria, M.V., Varella, R.A., Duarte, G.O., Farias, T.L., Baptista, P.C.: Engine cold start analysis using naturalistic driving data: city level impacts on local pollutants emissions and energy consumption. Sci. Total Environ. 630, 544–559 (2018) 19. García-Contreras, R., Armas, O., Mata, C., Villanueva, O.: Impact of Gas To Liquid and diesel fuels on the engine cold start. Fuel 203, 298–307 (2017) 20. Deng, Y., Liu, H., Zhao, X., E, J., Chen, J.: Effects of cold start control strategy on cold start performance of the diesel engine based on a comprehensive preheat diesel engine model. Appl. Energy 210, 279–287 (2018) 21. Bazdidi-Tehrani, F., Abedinejad, M.S.: Influence of incoming air conditions on fuel spray evaporation in an evaporating chamber. Chem. Eng. Sci. 189, 233–244 (2018)

Analysis of Operational Characteristics of Pneumatic Device of Industrial Robot for Gripping and Control of Parameters of Objects of Manipulation Volodymyr Savkiv1 , Roman Mykhailyshyn1 , Frantisek Duchon2 , Olegas Prentkovskis3, Pavlo Maruschak1(&), and Illia Diahovchenko4 1

4

Ternopil Ivan Puluj National Technical University, Ruska str. 56, Ternopil 46001, Ukraine [email protected] 2 Slovak University of Technology in Bratislava, Ilkovičova 3, 812 19 Bratislava, Slovak Republic [email protected] 3 Vilnius Gediminas Technical University, Plytinės g. 27, 10105 Vilnius, Lithuania [email protected] Sumy State University, Rymsʹkoho-Korsakova str. 2, Sumy, Ukraine [email protected]

Abstract. The advantages of application in the transport and loading systems of gripping devices with the integrated functions of control of parameters of objects of transportation were substantiated. Modeling of Bernoulli gripping devices with a possibility of dimensional check and weight objects of manipulation is offered. Modeling of dynamics of course of air flow in step nozzle and in a radial interval between the interacting flat surfaces of Bernoulli gripping devices and object of manipulation is carried out. For modeling based on RANS equation of dynamics of viscous gas, SST-model of turbulence and c-model of laminar and turbulent transition are used. As a result of numerical modeling in the program Ansys-CFX environment operational characteristics of Bernoulli gripping device and static characteristic of a measuring nozzle are defined. Keywords: Bernoulli gripping device
Air gaging
Object manipulation
Nozzle
Radial flow
Industrial robot
RANS
SST-model of turbulence

1 Introduction In transport loading systems, as operating parts of industrial robots, the gripping devices using aerodynamic effect of Bernoulli are widely used [1–6]. This effect consists in power interactions of the load proceeding from a screened nozzle of a current of air with a surface. Positive effects of this interaction can be used for different tasks: to hold loads by means of an aerodynamic attraction; without contact to transport © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 504–510, 2020. https://doi.org/10.1007/978-3-030-38666-5_53

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loads on a pneumatic pillow; to use reactive and force of viscous friction for orientation of objects of transportation. The combination of these effects of interaction allows to create essentially new devices for contactless capturing, orientation and transportation of objects of production. It is easy to integrate additional functions of a pneumatic method of measurement of a number of parameters of objects of transportation into these devices. The pneumatic method of measurement was widely used for control of the linear sizes [7–9]. This method of measurement provides high accuracy, allows to exercise remote control in hard-to-reach spots. The pneumatic method of measurement allows to control without contact easy to break and fragile details and also details with coverings which can be damaged by mechanical contact. It is easy to automate and operate air measuring devices, they have high reliability and durability of work. However the typical pneumatic method of measurement has considerable inertance that reduces measurement speed. For speeding up and the accuracy of a pneumatic method of measurement it is necessary to minimize volumes of flowing cameras, to use an ejector nozzle and modern high-precision and low-inertia pressure sensors.

2 Methodology In this article the pneumatic operating part of the industrial robot (Fig. 1), integrating functions of contactless gripper and deduction of the object of manipulation (OM) and also measurement of distance between their flat surfaces is offered. On the basis of data on distance between gripper and OM it is possible to determine the mass of an object or its thickness. Determination of manipulation object’s mass during the robot’s handling operations creates a number of additional opportunities for automation of the following processes: sorting of objects of production according to weight or control of a deviation of weight from necessary; definition of the inertial force operating on OM connected with acceleration (braking) of links of the manipulator that allows regulations of power characteristics of a gripping device and to carry out its reorientation for the purpose of decrease in energy consumption [10–13]. Additional function of determination of thickness of sheet material provides: incoming inspection before machining (for example grinding) flat wafers with information transfer about their thickness in local management system for calculation of the optimum mode of processing; final control, will allow at compliance of the valid size to necessary transfer them to further processing, and otherwise to leave in the previous position or to be enough and remove from technological process. When giving in the camera of 1 Bernoulli gripper (Fig. 1) of compressed air from the pneumotrunk it will follow through a step nozzle 2 in a radial gap between the flat surfaces of gripper and object of manipulation 3. Step the nozzle of Bernoulli gripper is designed so that at working values hc ¼ 0:15. . .0:25 mm distance, air flow tested the greatest narrowing at its input in a radial gap on radius rn. At the same time diameter d0 of a step nozzle is calculated so that cross-sectional area in this place of a nozzle was more than the area of critical section S* = 2prnhc, accepting rated value of a radial interval of hc = 0.25 mm. In step snivels 2 perpendicular to its axis the opening 5 with

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a diameter of 0.4–0.6 mm is executed connected by the channel 6 with the pressure sensor. Those which in most conform to requirements of accuracy, sensitivity and a small size will be the best pressure sensors in this case. At radial intervals of hc = 0.1–0.25 mm and excessive pressures of power of gripper by compressed air more than 30 kPa, the stream on radius rn reaches critical speed, equal to acoustic speed for these conditions. As a result of further increase in the area of a radial stream, its supersonic speed grows, and the static pressure upon a surface of OM decreases to size smaller atmospheric. At some distance from the center of a nozzle there is a sharp braking of a supersonic stream, to the subsequent its transition in subsonic that is followed by formation of pressure jump. As a result of further expansion the speed of a subsonic stream falls, and static pressure in a gap smoothly increases up to the size of atmospheric pa. Action of depression on a surface of OM leads to its levitation. Side shift of OM prevent an emphasis 4. Process of gripper of OM and the principle of measurement of weight of OM explain static characteristics of BGD and measuring nozzle are presented in Fig. 2.

Fig. 1. The constructive scheme of Bernoulli gripper with a step nozzle with additional function of control of distance to object of manipulation.

Fig. 2. Static characteristics of BGD and measuring nozzle (a – power characteristic of the BGD; b – static characteristic of a measuring nozzle).

Gripping of OM by the mass m happens from distance hcm that corresponds to a condition F(hcm) = mg (point 1 on Fig. 2a). The gripped object, under the influence of the growing Bernoulli’s effect, moves in the direction of a gripper end face with the increasing speed. At a radial interval hco gripper’s attraction force on an object reaches the maximum value Fmax (depending on diameters of a step nozzle of hco = 0.2–0.3 mm). Further the movement of an object slows down, at first due to reduction of size of force of an attraction, and later the account of the airbag which is pushing away actions. The elastic airbag will amortize dynamic action of an object, and then starts to push it away. The subsequent increase in distance between the interacting surfaces of gripper and an object leads to growth of force of an attraction, and an object at a given time will start over again

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moving in the direction of gripper. So, the gripped object carries out harmonious damped oscillations during time approximately equal 0:05. . .0:15 s. After attenuation of fluctuations the radial gap will automatically be established hst that corresponds to a balance condition F(hcs) = mg (point 2 on Fig. 2a). The principle of measurement of distance from an edge surface of BGD in OM consists in measurement of pressure ps in channel 6. The value of pressure ps changes over a wide range depending on value radial an interval (the diagram b in Fig. 2). Also value ps is influenced by pressure p0 in chamber 1 BGD and geometrical parameters of a step nozzle. For example, at hc ! 0 pressure in measuring channel 6 ps ! p0, and at hc > 0.5 mm in this channel due to ejection depression is created. So, the measured value of pressure ps in channel 6 characterizes the equilibrium provision hcs of a object of manipulation (point 3 on the diagram b), and according to its weight G = mg (point 2 on the diagram a). Reading of information from the pressure sensor ps it is necessary to carry out after the moment of gripper of OM and stabilization of data from the sensor (through 0.2–0.3 s after turning on of the electromagnetic distributor for supply of compressed air in the camera of 1 BGD). For definition of utilization properties of Bernoulli gripper it is necessary to carry out computational modeling of dynamics of course of air flow in step snivels and in a radial interval between the interacting surfaces of gripper and object of transportation. It is for this purpose used averaging on RANS equation of dynamics of viscous gas [14] turbulence SST-model [15, 16] and c-model of laminar and turbulent transition [17]. Use of c-model of laminar and turbulent transition allowed to improve convergence of iterations and to reduce time of calculations. The c-model of laminar and turbulent transition is described by one differential equation for alternation coefficient c: @ðqcÞ @ðqVj cÞ @ þ ¼ Pc  Ec þ @t @xj @xj


lþ

  lt @c ; rc @xj

ð1Þ

where q – air density; t – time; x – coordinate; V – vector of air velocity; Pc, Ec – respectively generative and dissipation members of managing directors of laminar and turbulent transition; l – molecular dynamic viscosity of gas; lt – turbulent dynamic viscosity of gas; rc = 1.0 – model constant. In c-model of transition use the modified equations of the SST-model:
 @ @ @ @k lim ~ ~ ðqkÞ þ ðqVj kÞ ¼ Pk þ Pk  Dk þ ðl þ rk lt Þ ; @t @xj @xj @xj

ð2Þ


 @ @ Pk @ @x ðqxÞ þ ðqVj xÞ ¼ a  Dx þ Cdx þ ðl þ rx lt Þ ; @t @xj @xj @xj vt

ð3Þ

where k – kinetic turbulent energy; x – the specific speed of dissipation of kinetic energy of turbulence; Pk, Dk – original generation and dissipation of the SST model ~ k ¼ maxðc; 0:1Þ
Dk ; Plim ~ k ¼ cPk ; D [19]; P k – the additional part, which provides the correct gain of turbulent viscosity in transitional area at very low level of turbulent viscosity of the running stream; dx – distance to the nearest wall; vt – turbulent kinematic viscosity of gas; rk, a – empirical constants of model.

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3 Results and Discussions Numerical modeling of dynamics of air flow in step nozzle and in a radial interval between the interacting surfaces of BGD and OM is carried out in the environment of computing hydraulic gas dynamics of Ansys-CFX with use of SST-model of turbulence and c-model of laminar and turbulent transition. For this purpose in settlement area the unstructured final and differential grid is constructed. Knots of a grid are united in volume elements (tetrahedrons and prisms). The total number of knots in settlement area makes 3.4 million, Total number of volume elements - 8 million, Total number of tetrahedrons – 3.4 million. As material are used air as ideal gas from libraries of the program. Boundary conditions for model of air flow are presented on Fig. 3, and on Fig. 4 the results of modeling in the form of lines of a current of elementary particles of air with display of their speed confirming existence in a radial interval of a supersonic current are presented.

Fig. 3. Limit conditions for air flow model.

Fig. 4. Streamline in the nozzle of BGD and in a radial interval (hc = 0.2 mm).

Computational modeling was carried out for JGD with such geometrical parameters: diameter of a throat of a nozzle of d0= 2.5 mm, outer radius of a conic facet of a nozzle of rn= 3 mm, d2= 3.5 mm, a = 1.8 mm, b = 1.0 mm, Δ = 0.2 mm, r1= 12 mm, rg= 30 mm, width of the rounded-off d = 0.3 mm facet. Height of a radial interval hc changed ranging from 0.05 up to 1 mm with a step of 0.05 mm. Excessive pressure in camera 1 BGD – 400 kPa. Attraction force gripper of a object of manipulation we determine by integration of distribution of depression (excessive pressure) pr on its flat surface: Zrg F ¼ 2p

pr rdr:

ð4Þ

0

As a result of integration of data of distribution of pressure upon surfaces of an object of manipulation at various values of a radial interval hc the schedule of dependence F(hc) (Fig. 5) is constructed. Also for various values of a radial interval hc

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pressure size in channel 6 is determined and it is constructed the static characteristic of a measuring nozzle presented in Fig. 6.

Fig. 5. Dependence of force of an attraction Bernoulli gripper of an object of manipulation from a radial interval hc.

Fig. 6. Static characteristic of a measuring nozzle of Bernoulli gripper.

It should be noted that a part of the schedule of dependence ps(hc) almost linear therefore for measurement of thickness of sheet material with the smallest error it is necessary to use the operating range of hc= 0.2–0.4 mm. High precision of measurement of object’s mass of manipulation is characteristic of the line section of dependence F(hc) too, that is corresponds to hc= 0.12–0.25 mm range for the set design data of a nozzle. In practice, for ensuring high precision of measurement of mass of objects of manipulation, it is necessary to try to obtain the maximum combination of these ranges of radial gaps due to selection of design data of a measuring nozzle.

4 Conclusions It is proved that Bernoulli grippers with a step ejector nozzle provide contactless contents and measurements of distance to objects of manipulation. At the same time an object is at some distance from the basic surface of gripper, and the force field in a radial interval affects evenly all its surface, without causing concentration of tension and without breaking the microrelief of its flat surface. The integrated function of pneumatic control of distance between the flat surfaces of gripper and object of manipulation allows to create robotic complexes for sorting of objects of production according to weight and operating control of their thickness. The mathematical model for numerical modeling of dynamics of airflow in step snivels Bernoulli gripping devices and in a radial interval between its active surface and a surface of a object of manipulation is presented. As a result of numerical modeling power characteristics Bernoulli gripping devices and static characteristic of its measuring nozzle are defined.

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For the set design data of Bernoulli gripper it is established that for measurement of thickness objects of manipulation with the smallest error it is necessary to use the operating range of radial gaps 0.2–0.4 mm, for measurement of their weight range 0.12–0.25 mm.

References 1. Li, X., Kagawa, T.: Development of a new noncontact gripper using swirl vanes. Robot. Comput. Integr. Manuf. 29(1), 63–70 (2013) 2. Official website of Festo AG & Co, Bernoulli gripper OGGB. https://www.festo.com/net/sv_ se/SupportPortal/default.aspx?cat=4564 3. Stühm, K., Tornow, A., Schmitt, J., Grunau, L., Dietrich, F., Dröder, K.: A novel gripper for battery electrodes based on the Bernoulli-principle with integrated exhaust air compensation. Procedia CIRP 23, 161–164 (2014) 4. Savkiv, V., Mykhailyshyn, R., Duchon, F., Fendo, O.: Justification of design and parameters of Bernoulli–vacuum gripping device. Int. J. Adv. Robot. Syst. 14(6), 1729881417741740 (2017) 5. Savkiv, V., Mykhailyshyn, R., Duchon, F.: Gasdynamic analysis of the Bernoulli grippers interaction with the surface of flat objects with displacement of the center of mass. Vacuum 159, 524–533 (2019) 6. Ozcelik, B., Erzincanli, F.: A non-contact end-effector for the handling of garments. Robotica 20(4), 447–450 (2002) 7. Jermak, C.J., Jakubowicz, M., Dereżyński, J., Rucki, M.: Air gauge characteristics linearity improvement. J. Control. Sci. Eng., 8701238 (2016) 8. Jermak, C.J., Rucki, M.: Static characteristics of air gauges applied in the roundness assessment. Metrol. Meas. Syst. 23(1), 85–96 (2016) 9. Jakubowicz, M., Derezynski, J.: The measuring position designed to determine the metrological properties of air gauges. Adv. Sci. Technol. Res. J. 11, 198–205 (2017) 10. Savkiv, V., Mykhailyshyn, R., Fendo, O., Mykhailyshyn, M.: Orientation modeling of Bernoulli gripper device with off-centered masses of the manipulating object. Procedia Eng. 187, 264–271 (2017) 11. Savkiv, V., Mykhailyshyn, R., Duchon, F., Mikhailishin, M.: Modeling of Bernoulli gripping device orientation when manipulating objects along the arc. Int. J. Adv. Robot. Syst. 15(2), 1729881418762670 (2018) 12. Mykhailyshyn, R., Savkiv, V., Mikhalishin, M., Duchon, F.: Experimental research of the manipulatiom process by the objects using Bernoulli gripping devices. In: Young Scientists Forum on Applied Physics and Engineering, pp. 8–11 (2017) 13. Savkiv, V., Mykhailyshyn, R., Duchon, F., Mikhalishin, M.: Energy efficiency analysis of the manipulation process by the industrial objects with the use of Bernoulli gripping devices. J. Electr. Eng. 68(6), 496–502 (2017) 14. Garbaruk, А.V.: Modern Approaches to Modeling Turbulence. Polytechnic University Publ., S. Petersburg (2016) 15. Menter, F.R.: Two-equation eddy-viscosity turbulence models for engineering applications. AIAA J. 32(8), 1598–1605 (1994) 16. Menter, F.R., Langtry, R.B., Vӧlker. S.: Transition modelling for general purpose CFD codes. J. Flow Turbul. Combust. 77, 277–303 (2006) 17. Menter, F.R., Smirnov, P.E., Liu, T., Avancha, R.: A one-equation local correlation-based transition model. Flow Turbul. Combust, 95, 583–619 (2015)

Riga International Coach Terminal: Safety and Security Risk-Based Decision-Making Approach Vaira Gromule1,2(&) and Irina Yatskiv (Jackiva)2 1

JSC Riga International Coach Terminal, Pragas 1, Riga 1050, Latvia [email protected] 2 Transport and Telecommunication Institute, Riga 1019, Latvia [email protected]

Abstract. Due to the constant growth of traffic between EU countries it is necessary to improve the interconnectivity between states, remove bottlenecks, and also to strengthen the robustness of transport infrastructure and the resilience of the overall network. The nodes such as the bus and rail station connecting regional and urban transport reflect the demand for novel intelligent solutions and farsighted infrastructure planning. The goal of the paper presents a study of the Riga International Coach Terminal (RICT) as an object of critical infrastructure. It should be in frame of resilient system and safety and security risk-based decision-making approach based on research. The company provides services to bus and coach undertakings and passengers and meets the requirements of a medium-sized enterprise. Authors analysed European and National level regulatory documents and trends in the field of passenger transport and transport infrastructure security. After RICT safety and security management system presented authors provides recommendations for structuring the security and risk management process, including interfaces with internal and external bodies. Keywords: Passenger terminal
Resilient system
Safety and security management system
Stakeholders
Data for risk assessment
Incidents

1 Introduction 1.1

Actuality

In the business environment of the 21st century, one of the driving factors of competitiveness is the ability to adapt, direct and accept innovative technology solutions. And technology development in mobility in the era of the vibrant globalised population is very rapid. People urban mobility in future will be increasingly intermodal – as stated in the Integrated Urban Mobility Roadmap [1] – with a balanced combination of public transport, new mobility services, shared and private vehicles and soft modes. Mobility is now crossing a new-digital-frontier with increasing new possibilities: “mobility as a service”, car-sharing schemes, electro-mobility, driverless vehicles, increasing automation and connectivity etc. And the actuality of security issues in implementing these innovations does not disappear. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 511–520, 2020. https://doi.org/10.1007/978-3-030-38666-5_54

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Due to the constant growth of traffic between EU countries it is necessary to improve the interconnectivity between states, remove bottlenecks, and also to strengthen the robustness of critical infrastructure and the resilience of the transport network in whole. The nodes such as the bus and rail station connecting regional and urban transport reflect the demand for novel intelligent solutions and farsighted infrastructure planning. The passenger terminal as critical infrastructure should be considered in the frame of resilient transport system [5, 6] and can be characterized in follows five dimensions (“R” features) as [4]: • Robustness means the ability to resist shocks and prevent disruptions; • Redundancy is excess capacity and back-up systems which enable core functions; • Resourcefulness is the ability adapts to crises, respond flexibly, deploy necessary resources to take action; • Response means the ability to mobilise quickly in the event of disturbances; • Recovery means the ability to regain a degree of normality after event, incl. flexibility and adaptability. In public transport the passenger is the main beneficiary of the security measures and at the same time together with the staff is the potential victim of resulting privacy breaches. And the long-term vision of the security approach should only be based on a dynamic ethical balance between societal benefits and prevention of unnecessary, intrusive methods, this balance changing rapidly with the local context, the international (security) situation or the evolution of the general use of technology [11]. Technological innovations at passenger terminals significantly increase the availability of useful data and workable information. Policy-makers need to understand likelihoods, impacts of incidents in a transportation environment and also to plan risk management on a system approach basis. 1.2

Research Methodology

The paper is focused on the object – Riga International Coach Terminal (RICT) and its safety and security management system (SSMS) as a research subject. RICT is a leader in the area of passenger bus transportation services in Latvia and security, and safety in passenger terminal is determinant for the feeling of satisfaction towards a service. The company provides services to bus and coach undertakings and passengers and meets the requirements of a medium-sized enterprise. One of the goals of the company’s business is to improve mobility services, but the business environment of RICT is heterogeneous and main research question in this study is how a company (RICT) could mitigate future risks in a fast-changing environment? Policy documents regulating security and safety consist of European, country and terminal regulations. Moreover the EU reports, guides, best practices and others may be useful for passenger terminal SSMS development. The EU 2011 White Paper [2] defined the creation of an Advisory Committee on land transport security as a priority initiative and

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sets out the EU transport research, innovation, and deployment strategy and highlights standardization and interoperability as keys to avoiding the technological fragmentation of the European transport market [4]. In fact, on a research level, there are several research activities going on and the set of the EU projects spotlight this topic: City-Hub [7], SECURED [8], SecureStation [9], etc. Gromule et al. in [4] analyzed European and National level regulatory documents and RICT security assessment and planning framework. And the aims of this study is analysis of the RICT as an object of critical infrastructure and review the different stakeholders’ collaboration and data sources in the frame of holistic risk-based decision-making approach for improving Terminal safety and security both from a policy and research background. Particular emphasis in research is placed on the collection of data for risk assessment in RICT: it is necessary to identify the threats and identify risks and to analyze possible data collection sources and data types for the risk assessment. In the next section, the authors have presented the RICT safety and security management system (SSMS). In Sect. 3 different sources of information for risk assessment were analyzed and in Sect. 4 first results of SSMS implementation and future development are presented. In the end, the paper provides recommendations for structuring the security and risk management process, which includes interfaces with internal and external bodies.

2 RICT Safety and Security Management System RICT SSMS is a complex process with many stages and activities. Similar to public transport security concept there are highlighted three interconnected elements, as mentioned in [10]: • Security organization setup (incl. interfaces with internal and external bodies); • Risk-based strategy; • Risk mitigation safeguards and policies (incl. operational arrangements, procedures, technological, communication and information management systems, physical protection means, incident response, and business continuity planning). One of the important tasks for RICT authorities is to implement a common procedure to identify all risks for this critical transport infrastructure and integrate fully security aspects into their day-to-day operations [4]. Developed and functioned RICT SSMS includes: (1) Procedures and methods for security design; (2) Process for security assessing, planning, implementation; (3) Security and safety assessment and planning framework and activities that is shown in [4]. Main RICT SSMS components are following [11]: 1. 2. 3. 4. 5. 6.

Maintenance of public order in RICT territory. Assistance to RICT carriers and passengers. Civil security measures in an emergency situation. Fire prevention measures and risk analysis. The possible risk of terrorist threat prevention. RICT Information systems and data protection.

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Vehicle traffic management and record keeping. RICT visitor traffic research and analysis. Cooperation with national and local safety authorities. Building technical structure safety monitoring. Protection measures of RICT employees. Personal data protection.

RICT, as a medium-sized enterprise, has very limited financial and human resources to attract security issues. Therefore, good cooperation with specialized security organizations with experience in servicing such objects - security guard service, etc. - is essential. The activities of the company are characterized by cooperation with a large number of cooperation partners - clients, suppliers, service providers, supervisory institutions, tenants, etc. (see Fig. 1 and Table 1), as well as the number of visitors up to 6 million people per year.

Fig. 1. Interactions between operators and stakeholders.

At the same time, it should be noted that a significant number of company employees are involved in the organization of the safety and security system, the activity of whom is regulated and coordinated (instructions, process descriptions) in documents and achieved by organized training. Description of risk – management processes is included in RICT Quality Management System (QMS). It consists of risk description, risk factors, probability, description of possible consequences, likelihood of sequencing, level of risk, mitigation or prevention of operational risks, performance evaluation of the actions, responsible and involved parties, deadline for implementation and necessary finances.

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Table 1. Operators and stakeholders. Operators and stakeholders Coach operators Municipal authority

Regulatory body

Passenger information system Ticket purchase services Dispatchers service Energy

Infrastructure Public safety Communication BTI Ltd. CERT.lV

Role description Give an environment to closer realize security occurrences and also instructions to take effective control and improvement action Give a summary of general collaboration in an exchange of information between coach terminal, public transport operators and other stakeholders The summary of general collaboration in the exchange of information between coach terminal, public transport operators and other stakeholders The passenger information system makes related information available to the passengers: routes, timetables, live traffic, etc. (e.g. through information displays, mobile applications, etc.) Ticket purchase services receive travel and payment Provides timetable data, condition data and manages traffic flow in the coach terminal Energy consumption data is useful for energy vendors to intensively adjust the grid in case of short-term and un unpredictable load conditions The exchange of information with infrastructure providers Monitoring data (e.g. surveillance video recordings) are shared with public safety authorities – the security stuff and the police Operational data exchange with 3d parties (Coach operators, travel agencies, etc.) Information system (IS) service provider The IT Security Incident Response Institution of the Republic of Latvia. Information about IT security threats. Support in the case of IT security incidents

3 Data for Risk Assessment and Analysis A very important phase in security and safety assessment and planning framework [4] is to understand the threats and identify risks. For RICT, there is identified following groups of threats: • physical, large-scale attacks: terrorism, vandalism and/or civil disorder, theft of data and/or infrastructures; • environmental and nature attacks: natural and environmental disaster, which include earthquakes, floods, wildfires, pollution, dust and corrosion; • technical risks: technical building structure; communication and technical resources; transport infrastructure and interruption/disruption of electrical supply; • IT and technological risks: not functioning and/or insufficient functioning of any IT infrastructure assets, cyber-attacks.

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The data collection for risk assessment and procedural or technical security solutions are strongly influenced by the growing role taken by information and communication technologies. RICT for business process organization uses different information systems (IS) and technologies. These systems compile, generate and contain data that can serve as a basis for identifying and assessing various risks. Table 2 shows data collection sources and data types for the risk assessment. Table 2. Data collection sources and data types for the risk assessment. No. Sources 1. Ticket sales and bus tracking system “BalticLines” 2.

3.

4.

5.

6. 7.

8.

Data types Responsible persons Real-time number of serviced passengers Company Real-time number of serviced buses management Terminal administrator Logistics department CRM and ERP Statistical information about the number Company system MS Dynamics of serviced passengers and buses (to management predict the workload of the coach terminal) Security and video Real-time number of security incidents in Company management surveillance system the area of the terminal Security staff Triggering of programmable security Terminal exchange triggers (left things, entrance to a administrator prohibited area, etc.) Dispatchers Car number Real-time number of vehicles located in Security staff recognition and the area of coach terminal Terminal exchange counting system administrator Dispatchers People flow counting Real-time number of people located in Company system the area of coach terminal management Terminal exchange administrator Security staff Luggage storage Real-time number of transferred luggage Company system management Bus and coach The flow of buses and people for normal Company passenger flow model operation of coach terminal management Logistics department Terminal exchange IoT based building Real-time and statistical data about administrator monitoring system temperature, humidity, and Carbone Dioxide gas level in the coach terminal Security staff Company building management

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Main difficulties of data collection: • A large amount of data; • Most of the data is not structured; • Most IS are closed systems and do not have application programming interface (API) for data exchange or trigger programming; • Data exchange protocols are not unified; • There is no universal tool for data processing; • Difficult to define the level of triggering of the specified parameters. One of the nearest tasks for RICT Management Board is to develop the module that should to enrich the information from all ISs by utilizing advanced analytical methods and tools (offered by Machine and Deep Learning, Big Data and other techniques) that provide the ability to recognise patterns, detect trends, and emerging threats on the basis on link analysis among data elements. As noted in [11] it should include analytic tools for advanced search capabilities into existing database sources, and generated queries to other sources: state and commercial data aggregators, to allow analysts to search several databases simultaneously. Figure 2 shows RICT safety and security system creation hierarchy.

Fig. 2. Operational security architecture hierarchy.

Previously done and the measures mentioned above cover 1–3 levels. Make important use of IT system performance improvement and data exchange raising by creating Threat Intelligence tool that would raise the system’s performance to a significant new level. Implementation of new technologies can bring expected positive impacts in safety and security, operations, cost-effectiveness, and user experience. However, likewise, it can increase elements of risk in the same categories. Connectivity and system integration that combine numerous components originating from different sources can lead a to gain of cyber-attacks.

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The current EC strategy built upon recommendations of the high-level group [3] that emphasize the need for a harmonised and error border regulatory framework for testing, communication, data security and safety, cybersecurity. This document stress that the European automotive sector is expected to undergo structural changes in its value chain due to the development of digital technologies and shift towards low and zero-emission mobility. The industry, in particular, SME’s, will need to assess and, if necessary, redesign their position in the value chain as well as increase their capacity to implement digital technologies in their operational process.

4 First Results of SSMS Implementation and Future Development RICT SSMS implementation needs to link to coach operations safety policy tasks, incident management and also investigation activities. A continuous, forehanded and well-designed process for identifying risks of different levels based on an effective incident reporting system. As part of the overall SSMS RICT developed control measures to eliminate or reduce identified risks and periodically review identified security risks and the measures used to reduce or eliminate the risks. Responsible persons using the procedures report security incidents and threats. In Table 3, the distributions of the RICT incidents between the types in 2017 and 2018 are presented. The total number of incidents is decreased by 20%.

Table 3. Distribution of the RICT incidents between the types in years 2017, 2018. No

Characteristics of incidents

1. 2. 3.

Technological disturbances IT program malfunction Personnel faults (all companies working in the security zone of RICT) Customer behavior problems Using alcohol or drugs Assistance for Restroom facilities staff Medical assistance provided Assistance provided to the café and other partner companies in the coach terminal Alarms at the Coach Terminal Others Terror Threat Others

4. 4.1 4.2 4.3 4.4 4.5 4.6 5. 6.

2017 % 10.9 3.2 5.3

2018 % 9 9.5 9.9

77.8 9.5 26.4 6.4 29.2

64.8 10.2 21.1 4.2 43.1

22.4 6.2 0.2 2.6

16.0 5.4 0.4 6.2

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As we see in Table 3 a high percentage from a total number of incidents is problems of customer behavior, and we see that it is decreased significantly. Technological disturbances are decreasing a little. This can be explained by the fact that technology is developing, and the compatibility of technological products is improving. But IT programs are becoming more sophisticated, more difficult testing and problem identification. Personnel qualifications also need to be continuously promoted to work with new programs. The partner evaluation system allows to identify problems and errors, improved collaboration with partner companies, regular training and briefing, all this reduce personnel faults. Terrorist threat category includes false alarms from third parties. The incidents referred to in the last row (6) are related to vehicle movement disorders. A lot of research questions (subjects) still open for RICT. For example, it is useful to model the safety and mobility behaviour of multimodal transportation users (PT passengers) and the influence of external factors on it. It is very important to include in the research the analysis of the risk appraisal and risk acceptance level of different traveller groups with participants of mixed sociocultural backgrounds, i.e. migrants, tourists, international students, persons with disabilities etc. Of course, the data based on different sources are critical for such question’s solutions. It is necessary to improve the data collection tools and procedures for the different contributing factors considering advanced sensing, data merging approaches, advanced analytics for Big Data. To explore the impact of advanced technologies (MaaS, C-ITS, Internet of Things, connection and automation), it is very important to use the holistic approach for their implementation and using for the different aspects surrounding travellers’ behavioural monitoring, modelling and adaptation place in the centre safety and security aspects.

5 Conclusion The development of information and communication technologies and their impact on other developments is essential and important for all sectors of the economy, significantly increasing their work efficiency and competitiveness of enterprises. In the national economy of Latvia, the largest proportion of enterprises is SMEs, competitiveness and operational efficiency of digitalisation and robotisation is an important decision both from the point of view of operations processes organization and financial adequacy. The EU regulatory framework, national laws, as well as studies involving methodologies and tools, are complicated for small and medium-sized enterprises. The implementation of new technologies, not only from the point of view of technology, but also the public safety and security aspect, should be shaped as a more practical solution in form of handbooks and manuals. This paper is the step to cover this gap and shows how policy framework can be translated into practical research, and it did for RICT as an example of such an enterprise. To better coordinate research in security and safety; its implementation, policymakers and business need to give the possibility to researchers to be involved more actively in such processes and cooperation between scientific, educational institutions and enterprises will mitigate future risks for SME a fast-changing environment.

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In order to guarantee a new advanced approaches and technologies application more concrete policy guidelines and initiatives are needed. For instance, for this research continuation, it is important to solve the problems of data integration and fusion from different sources and IT systems in RICT. So, research may set the starting point for innovation and practical implementation.

References 1. European Commission: Action Plan on Urban Mobility (2009) 2. EU White Paper - Roadmap to a single European transport area - Towards a competitive and resource-efficient transport system (COM (2011) 144 final of 28 March 2011) 3. European Commission, GEAR 2030, Final report-2017, DG GROW – Internal Market, Industry, Entrepreneurship and SMEs, October 2017 4. Gromule, V., Yatskiv, I., Pēpulis, J.: Safety and security of passenger terminal: the case study of Riga International Coach Terminal. Procedia Eng. 178, 147–154 (2017). I. Kabashkin, I. Yatskiv (Jackiva) and O. Prentkovskis eds. 5. Ganin, A.A., Massaro, E., Gutland, A., Steen, N., Keister, J., Kott, A., Mangoubi, R., Linkov, I.: Operational resilience: concepts, design, and analysis. Sci. Rep. 6, 19540 (2016) 6. Fiksel, J., Goodman, I., Hecht, A.: Resilience: navigating toward a sustainable future. Solutions 5(5), 38–47 (2014) 7. Monzon, A., Di Ciommo, F.: City-Hubs, Sustainable and Efficient Urban Transport Interchanges. CRC, Taylor and Francis Group, Boca Raton (2016) 8. SECUR-ED, White Paper for Public Transport Stakeholders (2014) http://www.secur-ed.eu/ wp-content/uploads/2014/12/SECUR-ED_White_Paper_Final.pdf 9. SecureStation - Passenger station and terminal design for safety, security and resilience to terrorist attack (2013). http://www.securestation.eu/ 10. Yatskiv (Jackiva), I., Savrasovs, M., Gromule, V., Zemljanikins, V.: Passenger terminal safety: simulation modelling as decision support tool. Procedia Eng. 134, 459–468 (2016) 11. Yatskiv, I., Gromule, V.: Holistic approach to passenger terminal risk estimation. In: Frenkel, I., Lisnianski, A. (eds.) Proceedings of the Second International Symposium on Stochastic Models in Reliability Engineering, Life Science and Operations Management (SMRLO 2016), Beer Sheva, Israel, 15–18 February 2016, pp. 643–649 (2016). https://doi. org/10.1109/smrlo.2016.114

Use of Container and Piggyback Services in International Railway Traffic Mykola Kurhan1(&) 1

, Laura Černiauskaitė2, and Dmytro Kurhan1

Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan, Lazaryan str. 2, Dnipro, Ukraine [email protected], [email protected] 2 Vilnius College of Technologies and Design, K. Kalinausko str. 7, 01100 Vilnius, Lithuania [email protected]

Abstract. A modern cargo owner imposes rather strict requirements on transport services in terms of delivery time, cargo safety, quality of forwarding services. In the current conditions, it is necessary to explore the possibility of developing new additional types of carriage on rail transport, in close cooperation with the road transport. In the interaction of rail and road transport the reliability, speed and carrying capacity of the first one is combined with the flexibility and efficiency of the other. However, many issues within the framework of interaction between rail and road carriers still require scientific solutions – from the selection of criteria to a comprehensive assessment of the effectiveness of piggyback transportation. Principles of transport service quality management were formulated and evaluation criteria were determined. Piggyback traffic in the direction of Odessa-Klaipeda will allow Ukraine, Belarus and Lithuania to maintain roads, ensure purity of environment, make it possible to save fuel, as well as allow owners and carriers to significantly reduce operating costs and improve the quality of services provided. Keywords: Railway transport


Container services
Piggyback services

1 Introduction The problem of improving the existing and introducing new technologies for the transportation of goods has long been a concern for transport systems of many countries. The transition to a market economy has led to a significant redistribution of traffic between different types of transport. In this situation, rail transport is not in the best position. Reduced traffic volumes, some of which are being developed by road transport, led to the decrease in railroad revenues, excess of technical equipment, personnel, etc. A promising area for obtaining additional volumes is the international carriage of goods, where motor transport has become particularly active recently. The geographic scope of the OSJD (Organisation for Cooperation between Railways) covers more than 280 ths. km of railway lines in 28 countries of the world, carrying almost 6 billion tons of cargo and more than 4 billion passengers a year. Naturally, time plays an important role in this space for the successful provision of © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 521–530, 2020. https://doi.org/10.1007/978-3-030-38666-5_55

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railway services. Therefore, the main activities are the development and improvement of international rail traffic, including the combined one, both between European countries and between Europe and Asia, and the work to reduce the interstate border passing time for trains. A special role in the organization of such a transport connection falls on the countries that are not only the senders (recipients) of cargo flows, but also transit countries. Due to its geographical location and a developed transport infrastructure, Ukraine has significant potential in the development of freight traffic, primarily as a transit country in the logistics chain of trade between Asia and Europe. On the territory of Ukraine there are 5 international transport corridors; the total length of these routes is about 6.5 thousand km, thereof 3.5 thousand are railway lines. In 2016, Ukraine joined the Coordination Committee for the Development of the Trans-Caspian International Transport Route (TMTM) to China through Georgia, Azerbaijan and Kazakhstan. Railway transport in Ukraine is the main carrier of goods, which accounts (excluding pipeline transportation) for 65% of all freight traffic and 81% of freight turnover, about 50% of passenger traffic. In 2017, international carriage accounted for more than 50% of the total rail freight traffic. In the structure of international rail traffic, the largest share is export cargo – 42%, for comparison, import – 12%, transit – 11%. The possibilities of rail transport for organizing transportation between the countries of the European Union and Ukraine are not fully used, since there are several technical issues concerning incompatibility of the transport systems of Ukraine and European countries, namely: different gauge, rolling stock characteristics, type of signaling system, overhead system voltage, dimensions, etc. [1]. The search for scientific solutions to the unification of technical systems within the organization of international transport corridors is also relevant for other European countries. For example, one can mention the scientific research conducted in this area in Poland [2], Hungary [3], Lithuania [4, 5], Ukraine [1, 6] and others. A modern cargo owner imposes rather strict requirements on transport services in terms of delivery time, cargo safety, quality of forwarding services. In the current conditions, it is necessary to explore the possibility of developing new additional types of carriage on rail transport, in close cooperation with the road transport. Such transportation will create a continuous transport chain from the shipper to the consignee, satisfying the increased customer requirements for the quality of services provided, and taking full advantage of each type of transport. In the interaction of rail and road transport the reliability, speed and carrying capacity of the first one is combined with the flexibility and efficiency of the other. Of all the types of combined transport, which include container, piggyback, bimodal transport, swap body transportation, etc., only the first type has become widespread. Without a doubt, the container system is the fastest growing type of combined transport in the world, covering all large freight traffic. Intermodal transportation passing the territory of Ukraine is shown in Fig. 1 [7]. The use of piggyback transportation in Europe is expedient, because environmental costs are reduced to 200 million, the road repair cost to 0.5 billion euros per year. At the same time, the cost of delivering goods by rail is three times lower than by that by road.

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The Viking combined transport train [8] is a joint project of the railways of Lithuania, Ukraine and Belarus, stevedore companies (stevedore is a company engaged in loading and unloading ships) and the ports of Klaipeda, Chornomorsk and Odessa. The 1,733 km long route passes through Ukraine, Belarus and Lithuania and connects the chain of sea container and piggyback lines of the Baltic region with a similar system of the Black, Mediterranean and Caspian Seas (Fig. 1). The regular operation of the Viking combined transport train started on February 6, 2003. The delivery of goods by road cost $ 750, and the delivery of one motor car by rail cost $ 450. From Chornomorsk to Klaipeda by sea, goods are transported for about 15 days, and by rail – 2.5 days. The largest share of the route falls on Ukraine (44.0%) at a transport speed of 33.8 km/h, the route on the territory of Belarus covers 31.4% (at speed of 24.4 km/h), on the territory of Lithuania – 434 km (at speed of 27.1 km/h).

Fig. 1. Scheme of intermodal transportation by the territory of Ukraine [7].

Taking into account the prospects of the Viking project in the area of attracting additional volumes of cargo transportation, its geography is gradually expanding: 2012 – “BDZ – Freight Services” Ltd. (Bulgaria); 2013 – Moldovan Railway state enterprise; 2014 – CFR Marfa SA; 2015 – Georgian Railway JSC; 2016 – Azerbaijan Railways CJSC. Today the route passes through Bulgaria, Romania, Moldova, Azerbaijan, Georgia, Ukraine, Belarus and Lithuania and connects the chain of marine container and piggyback lines of the Baltic region with a similar system of the Black and Caspian Seas [9].

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However, many issues within the framework of interaction between rail and road carriers still require scientific solutions – from the selection of criteria to a comprehensive assessment of the effectiveness of piggyback transportation. In practice, when distributing carriages, the mode of transport can be chosen on the basis of current tariffs, which cannot be considered correct. Reflection in the tariffs of the average labour costs, incompatibility by means of transport, not taking into account the traffic regularity, etc. may lead to erroneous conclusions when choosing a mode of transport. The difference of the new tariff system, which is applicable on the railway transport, is that the base rate is linked to the railway transportation indicators that affect the prime cost. As for the economic component itself, the MTT [10] provides for a substantial reduction in the level of tariffs for export and import piggyback transportation.

2 Selection of Criteria Given the experience of economic evaluation of export shipments, it is considered appropriate to use such indicators that meet the requirements of consumers: traffic safety at all stages of transportation; commercial speed (characterizes the export cargo delivery time); service regularity; timely delivery; cargo safety; the average cost of transporting 1 ton of export cargo; level of freight forwarding services. Taking into account the above, principles of transport service quality management were formulated and evaluation criteria were determined, Table 1. Table 1. System of criteria for evaluating direct road and combined transportation. 1. Technical efficiency as the 2. Safety and reliability transport functioning quality measure

3. Costs in monetary terms

4. Time or time savings

– traffic capacity; – traffic safety and regularity; – prime cost of – vehicle – carrying capacity; – cargo and environmental transportation; travelling – speed and timing of cargo delivery; safety; – required time; – maneuverability of transport; – maintaining the ability to investments; – locomotive – need for fuel and electricity, perform transport functions. – cost of cargo turn-around etc. mass being time; transported; – wagon turn– damage to the around time, environment; etc. – cargo transportation tariffs.

As the economic indicators reflect practically all aspects of the transport operation, when comparing options, economic aspects were considered first of all, and then quantitative and qualitative indicators were taken into account. The decisive indicator when choosing a mode of transport for freight traffic is considered the prime cost of transportation and specific capital investments in fixed and current assets.

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The prime cost of transportation is determined by the monetary expression of current expenditures for the performance of the transportation unit. Ci ¼

Oi ; ðGLÞi

ð1Þ

where O = Om + Ot + Ord – operating costs associated respectively with mileage (fuel, lubrication, maintenance, …), time (salary, depreciation, …), maintenance of track facilities (road component); GL – freight turnover (volume G multiplied by transportation range L), tkm. However, it is incorrect to compare the average (reported) figures on the prime cost of transportation by rail and motor transport, since they are calculated for different values of the load and transportation range. Herewith, the road maintenance cost (road component) is not included in the prime cost of motor transport. Another criterion is the minimum labour costs for the delivery of products from the supplier’s warehouse to the consumer’s warehouse, that is, along the entire route. The specified criterion is as follows: for direct road transportation. Tm ¼ Om þ Dm þ En ðKm þ Cm Þ

ð2Þ

For combined transportation, Fig. 2. Tc ¼ Tm þ Tr ;

ð3Þ

where Tr = Сh + Сst + Or + Dr + Еn ( К r + Сr ); Om, Or – current annual operating costs, respectively, for motor and rail transport; Dm, Dr – damage caused by transport to the environment; Кm, Кr – one-time capital costs and cost of rolling stock; Cm, Cr – cost of cargo mass (circulating funds); Ch, Cst – costs respectively for cargo handling and storage at the stations; En – capital efficiency norm coefficient.

Fig. 2. Piggyback turn-around scheme: 0 – running of motor vehicles to a departure station and from a destination station to a consignee (L1, L2); 1 – movement operations (spotting the train), loading of tractor trucks with semi-trailers onto flat cars; 2 – train running along the section (Lr); 3 – car handling at district and shunting stations; 4 – movement operations, unloading of motor vehicles.

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When determining the operational and capital costs on rail transport, the traction type, the number of main tracks, the track gradient, the train weight, etc. were taken into account. When making calculations for road transport, the type and capacity of vehicles, road categories, speeds, etc. were taken into account.

3 Costs for Direct Goods Transportation by Road Current expenses for direct goods transportation by road (euro/ton) can be presented in expanded form: O¼

em L et ðL þ bVtech tlu Þ erd L þ ; þ abq abq
Vtech a

ð4Þ

where em, et, erd – expense rates related respectively to mileage, time and maintenance of roads; adopted for work [7]; q – carrying capacity of a semitrailer; a, b – coefficients of the use of vehicle load capacity and mileage, respectively; Vtech – technical speed; tlu – duration of the vehicle loading and unloading. The atmosphere pollution damage by emissions from motor vehicles when using cars with diesel engines was calculated by the formula D¼

3:88L : abq

ð5Þ

Capital investments in rolling stock and permanent devices of vehicles were determined by the formula

Кm =

(

100te Cmv + C f

)

365 K fl tdu ⋅ abq ⋅ Vtech

,

ð6Þ

where Cmv, Cf – cost, respectively, of the vehicle and production and technical facilities, referred to one motor vehicle; kfl – fleet utilization rate; tdu – duration of the vehicle on duty. te ¼

L þ bVtech
th ; bVtech

ð7Þ

where te – time of one journey. The circulating tangible assets were calculated using the formula similar to that used in railway transport. Cm ¼

100Ccrg Am ; 365

ð8Þ

where Ccrg – average cost of 1 ton of cargo; Oa – the turn-around of a motor vehicle.

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4 Costs for Goods Transportation by Rail Operating costs for rail transportation were calculated by the formula: O ¼ elu þ emb þ etm L þ enh Nnh þ ewh Nwh þ efe L þ est ;

ð9Þ

where elu, emb, etm, enh, ewh, efe, est – expense rates for corresponding indicator: loading and unloading, train making up and breaking up, train movement, service at stabling points, respectively, with and without handling of rolling stock, maintenance of fixed equipment and cargo storage [7]; Nnh, Ntr – the number of stations without car handling and with train remarshaling. To determine the cost of rolling stock for the carriage of goods by rail, it is necessary to calculate the required number of piggyback cars, the operational number of which will be equal to: Npb ¼

GApb c ; 365aq

ð10Þ

where Apb – piggyback car turn-around time determined in accordance with [7]; c – transportation irregularity coefficient. Calculations were carried out for various initial data (cargo transportation range, speed, capacity of vehicles, etc.). Separate calculation results are presented in the form of graphs (Figs. 3, 4 and 5).

Prime cost, %

100 80 60 40 20 0 0

100

200

300

400

500

600

700

Transportation range, km Cp(m)

Cp(r)

Fig. 3. Dependence of prime cost of transportation on transportation range.

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Specific cost, %

100 80 60 40 20 0 0

100

200

300

400

500

600

700

800

Transportation range, km Ttkm(m)

Ttkm(r)

Fig. 4. Dependence of reduced costs, referred to 10 tkm, on transportation range.

Specific cost, %

100 80 60 40 20 0 0

100

200

300

400

500

600

700

800

Transportation range, km Tt(m)

Tt(r)

Fig. 5. Dependence of reduced costs, referred to 1 ton of cargo, on transportation range.

5 Comparison of Variants Figures 3 and 4 show, respectively, the graphs of the prime cost of transportation Cp(m), Cp(r) and the specific reduced costs Ttkm(m), Ttkm(r) for by motor and rail transportation of goods at the same technical speed of 40 km/h. The analysis of dependence Cp(r) has shown that, in contrast to motor transport, with an increase in the range, the cost of transport by rail is sharply reduced. With the same transportation range, the equality of the reduced costs Ttkm(m) = Ttkm(r) and the prime cost of transportation Cp(m) = Cp(r) takes place at a range of 270–300 km for the initial data used in the study. Similar results were obtained when comparing variants for reduced costs per 1 ton of cargo, Fig. 5. The graphs Tt(m) and Tt(r) and have a linear dependence on the transportation range. Equality Tt(m) = Tt(r) takes place when the transportation range is 280 km.

Use of Container and Piggyback Services in International Railway Traffic

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Thus, almost the same results were obtained both for the prime cost of transportation and for the specific reduced costs. For comparison and subsequent analysis of economic indicators for the adopted initial data, the calculations were performed for different transportation ranges. We considered several options: from 100 to 1,200 km. The obtained results allowed to calculate the efficiency factors (Table 2): k1 ¼

TtðmÞ TtkmðmÞ CtðmÞ ; k2 ¼ and k3 ¼ TtðrÞ TtkmðrÞ CtðrÞ

ð11Þ

The analysis of the factors (Table 2) shows that the effectiveness of piggyback transportation increases with increasing transportation range, whichever economic criterion is considered. Thus, it can be considered that according to economic criteria, with a range of cargo transportation over 250–300 km, there comes the sphere of efficiency of piggyback transportation. Table 2. Values of transport efficiency factors. Transportation range, km Values of factors k2 k1 100 2.39 1.44 300 3.65 1.98 1000 4.20 2.19

k3 1.95 2.64 2.90

6 Conclusions 1. Taking into account all the diversity of the initial data (load capacity of vehicles, ratio of the movement speeds by road and rail, length of the supply line, cost of goods transported, etc.), we can assume that by almost all economic criteria for the cargo transportation range over 250–300 km piggyback transportation is efficient. 2. Handling of rail traffic on easy track layouts, as compared with a difficult one, leads to a reduction in the specific reduced costs and prime cost of transportation by only 4–6%. 3. In this work, the piggyback handling was provided with the help of truck tractors and a front metal or reinforced concrete ramp. Such costs make up to 15% of total expenses. The experimental journeys of the piggyback train (Dnipro - Lviv - Chop Záhony and back via Lviv to Kiev) showed that many operations, including loading-unloading can be cheapened if produced from a high platform on a deadend track. Thus, the reduction in the cost of handling operations and the cost of fixing the piggybacks by 1/3 leads to a decrease in the specific reduced costs and prime cost of transportation from 6 to 10%.

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4. It has been established that the use of heavy-duty semitrailers for the carriage of goods leads to a reduction in the need for rolling stock, both road and rail one. If instead of a semi-trailer with 20 ton carrying capacity (for example, MAZ-9397), one uses semi-trailers of 26 ton carrying capacity (for example, MAZ-9358), then the specific reduced costs and prime cost of transportation are reduced by 11–12%. When using semi-trailers with a carrying capacity of 32 tons (for example, MAZ9398) instead of 26 tons, the reduced costs and prime cost of transportation drop by 8–10%. 5. For the intensification of international traffic, piggyback fixed trains should be put into circulation (on difficult sections of 20 piggyback cars, on other sections - of 30–40). The introduction of such trains will accelerate the delivery of goods, reduce the piggyback car turn-around, and increase the efficiency of transport services. 6. Piggyback traffic in the direction of Odessa-Klaipeda will allow Ukraine, Belarus and Lithuania to maintain roads, ensure purity of environment, make it possible to save fuel, as well as allow owners and carriers to significantly reduce operating costs and improve the quality of services provided.

References 1. Kurhan, M., Kurhan, D.: The effectiveness evaluation of international railway transportation in the direction of “Ukraine – European Union”. In: Transport Means 2018, Proceedings of the 22nd International Scientific Conference, Trakai, Lithuania, 3–5 October 2018, Pt. I, pp. 145–150 (2018) 2. Tarapata, Z.: Modelling and analysis of transportation networks using complex networks: Poland case study. Arch. Transp. 36, 55–65 (2015) 3. Horvat, F., Fischer, S.: Magistrale for Europe. Közlekedésépítési Szemle 59(5), 33–37 (2009) 4. Cerniauskaite, L., Sakalauskas, K., Massel, A.: European-standard railway line between Vilnius and Kaunas. In: The 7th International Conference on Environmental Engineering, pp. 1125–1129 (2008) 5. Vaičiūnas, G., Steišūnas, S.: Investigation of priority directions of Rail Baltica extension from Warsaw. Procedia Eng. 187, 40–45 (2017) 6. Shevchenko, A., Matviienko, O., Lyuty, V., Manuylenko, V., Pavliuchenkov, M.: Ways of introduction of the high-speed movement of passenger trains in Ukraine. In: 7th International Scientific Conference “Reliability and Durability of Railway Transport Engineering Structures and Buildings” (Transbud-2018), MATEC Web of Conferences, vol. 230, p. 01014 (2018) 7. Kurhan, M.B., Kurhan, D.M.: Scientific-technical support of the railway Ukraine - European Union, Dnipro, Ukraine, 268 p (2018) 8. Viking Train. http://www.vikingtrain.com. Accessed 01 Mar 2019 9. Government portal: Ukraine and Lithuania note the increase in commodity turnover and strengthen the logistics capabilities of the two countries. https://www.kmu.gov.ua/ua/news/ ukrayina-ta-litva-vidznachayut-zrostannya-tovaroobigu-ta-posilyuyut-logistichnimozhlivosti-dvoh-krayin-zustrich-glav-uryadiv. Accessed 01 Mar 2019 10. International railway transit tariff (Tariff 8100). Official Edition of OSJD. http://osjd.org/ dbmm/download?vp=51&load=y&col_id=2066&id=2910. Accessed 01 Mar 2019

Influence of Parameters of Electric Locomotive on its Critical Speed Irina Klimenko1

, Jan Kalivoda2

, and Larysa Neduzha3(&)

Department of «Advanced Mathematics», Dnipro National University of Railway Transport named after Academician V. Lazaryan, Lazaryan St. 2, 49010 Dnipro, Ukraine 2 Faculty of Mechanical Engineering, Czech Technical University in Prague, Technická 4, 166 07 Prague 6, Czech Republic [email protected] 3 Department of «Theoretical and Structural Mechanics», Dnipro National University of Railway Transport named after Academician V. Lazaryan, Lazaryan St. 2, 49010 Dnipro, Ukraine [email protected] 1

Abstract. A high speed is one of the most important todays requirements for the rail transport. However, increasing the maximum speed brings also the problem of vehicle stability. The parameters of the vehicle suspension should be tuned in order to achieve vehicle stability in the entire speed range. The article presents the results of theoretical study of the impact of the suspension parameters of the mainline electric locomotive type DS3 on the magnitude of its critical speed. The stability and critical speed are assessed by eigenvalues calculation of the linear model of the vehicle. The study compares 9 variants of vehicle parameters. The sensitivity of the critical speed on the individual parameters is shown and discussed. At the same time, it is shown that by tuning vehicle parameters in order to achieve high critical speed, some other vehicle characteristics may deteriorate. As the result, the optimal range of the stiffness values of the connection of axle-boxes and bogie-frame is recommended. Keywords: Electric locomotive Linear model
Eigenvalues


Critical speed
Suspension parameters


1 Introduction The economic situation and development of the state strongly depend on the performance of its railway transport system. Environmental friendliness and high carrying capacity are important arguments for choosing the rail transport as the optimal type for the future [1–4]. Currently, the railway transport faces the following tasks: increase in the capacity and axial loads of freight trains; using energy-saving technologies; modernization and renewal in order to meet the current European standards; traffic safety improvement, passenger comfort improvement, increase of operating speed, etc. Effort to meet these requirements creates the need to improve the existing and create the new types of © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 531–540, 2020. https://doi.org/10.1007/978-3-030-38666-5_56

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rolling stock. These tasks and requirements determine also the improvement of the design of locomotives and especially their running gear. Current demands influence the formation of required dynamic qualities, because basic operational and economic indicators depend on the technical characteristics [5, 6].

2 Problem Statement Increased train speeds require the improvement of methods for assessing the dynamic qualities of railway rolling stock. Some of these qualities can be assessed by examining the motion stability, which is impossible without proper mathematical models. This results in strengthening of the role of mathematical modelling when solving the problems of rolling stock dynamics, as well as demand for deep theoretical and experimental studies with the use of modern methods [7, 8, 15–18]. Numerous theoretical studies show, and experimental data prove, that the necessary condition for the satisfactory dynamic qualities and unperturbed motion of rail vehicles is the asymptotic stability, in the sense of Lyapunov. This phenomenon is especially important at high speeds of motion, since in this case the vehicle may exceed its critical speed and lose stability [9–12]. Consequently, the amplitudes of displacements and accelerations of vehicle components as well as the horizontal transverse forces acting on the track increase rapidly. This entails intensive wear not only of the rolling stock, but also of the track elements. Therefore, when designing rail vehicles or modernizing them, the values of the suspension parameters must be chosen so that the critical speed would be higher than the design one [13, 19]. The maximum speed of the locomotive can be determined by different limits depending on the strength characteristics, dynamic qualities, the impact on the track, etc. The lowest value of the highest speeds, corresponding to different restrictions, will be the maximal permissible vehicle speed. It is usually assumed, for a correctly designed locomotive, that such the maximal permissible vehicle speed is also its design speed. Nevertheless, according to the recommendations of the relevant regulatory literature, the design speed of the vehicle is often selected so that the maximal permissible speed is by 10–15% higher than design speed. The design speed is a crucial value without which it is impossible to neither calculate nor test an electric locomotive. The Locomotive Design Standards [8, 14] state that the design speed is decisive when determining the solid dimensions of the locomotive structures, since in the operating mode, the highest values of the acting forces are determined by the design speed magnitude. For example, the long-term practice of designing and building locomotives has established the relationship between the design speed and the static deflection of the locomotive suspension. It is recommended that the static deflection of the suspension in millimeters should be equal to or slightly higher than the value of the design speed in kilometers per hour. Herewith it is clear that the elastic properties of the suspension depend on the design speed magnitude. It is also accepted that the coefficient of viscous friction in the suspension is a certain part (0.2–0.3) of the critical damping value, which also depends on the suspension stiffness. Thus, the dimensions of the locomotive structures, and the parameters of the elastic and dissipative suspension elements strongly depend on the design speed magnitude [19].

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3 Findings A mandatory component of scientific and technical developments of a new generation of railway vehicles is the study of their motion stability. The purpose of this study is to find such a set of parameter values and corresponding technical solutions, at which the critical speed of a vehicle exceeds the design speed. The motion stability can be inferred by Lyapunov’s first approximation, solving a system of linear differential equations that describes the perturbed motion of the vehicle. This was performed for a high-speed electric locomotive of DS3 type designed in Ukraine by a number of scientific and industrial organizations in cooperation with Siemens Company. The Branch Research Laboratory of the Dynamics and Strength of Rolling Stock (BRL DSRS) of the Dnepropetrovsk National University of Railway Transport (DNURT) carried out the theoretical studies of the stability of unperturbed motion of this locomotive [13, 14]. The system describing the motion of the locomotive running along the track was built. It consists of fifteen solid bodies (car body, two bogie frames, four intermediate beams, four gearboxes of traction motors, four wheel set) and track mass reduced to the wheel-rail contact points that move in two directions. This system has 50 degrees of freedom in total, it is described by linear differential equations which form a matrix of coefficients of the linearized equation system [13, 14]. The speed at which the largest real part of the eigenvalues of this matrix became equal to zero is considered as the critical. At motion speeds higher than the critical one at least one eigenvalue has the real part greater than zero. This corresponds to the presence of a form of oscillations with a positive increment, the corresponding amplitude increases in time, which leads to a significant deterioration in the locomotive running characteristics. Since the calculations were carried out in parallel with the design of the electric locomotive, changes and clarifications were gradually made to the locomotive parameters. The parameter values were provided by the project organizations, either after theoretical calculations or based running dynamic tests [13, 19]. Table 1 show the 9 variants which have arisen in the process of locomotive development and the nominal values of their important parameters. Table 1. Design variants and their parameters. Parameter Unit kkx kky kkz kbx kby kbz kbw m

kN/m kN/m kN/m kN/m kN/m kN/m kN/m t

Variant 1 197 155 327 70,000 5,000 1,960 283 51.38

no 2 91 155 417 70,000 5,000 1,960 192 51.38

3 91 155 417 70,000 5,000 1,610 192 51.38

4 91 155 417 56,000 3,800 1,500 192 51.38

5 91 155 417 29,400 3,460 1,452 192 51.38

6 91 155 417 20,000 3,000 1,300 192 51.38

7 91 155 417 43,000 4,000 1,610 192 51.38

8 9 91 91 155 155 417 417 50,000 70,000 4,200 5,000 1,610 1,610 192 192 51.38 48.9 (continued)

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Parameter Unit mT mk Ix Iz Ikz Imx Imz

t t tm2 tm2 tm2 tm2 tm2

Variant 1 11.3 3.84 162 648 4.04 10.7 11.9

no 2 11.3 3.84 171.3 808.3 4.04 6.54 17

3 11.3 3.84 171.3 808.3 4.04 6.54 17

4 11.3 3.84 171.3 808.3 4.04 6.54 17

5 11.3 3.84 171.3 808.3 4.04 6.54 17

6 11.3 3.84 171.3 808.3 4.04 6.54 17

7 11.3 3.84 171.3 808.3 4.04 6.54 17

8 11.3 3.84 171.3 808.3 4.04 6.54 17

9 10.77 3.77 106.2 794.5 2.743 5.477 14.135

Where kkx ; kky ; kkz – denote the stiffness of one spring of the suspension between the bogie and car-body; kbx ; kby ; kbz ; kbw – denote the stiffness of the connection of axle-box and bogie-frame; m – denotes the mass of the car-body with equipment; mT – denotes the mass of the sprung parts of the bogie; mk – denotes the mass of the unsprung parts of the bogie, related to one wheelset; Ix ; Iz – denote inertia moments of the car-body; Ikz – denotes the inertia moment of the unsprung parts of the bogie, related to one wheelset; ITx ; ITz – denote inertia moments of the sprung parts of the bogie. The index x represents longitudinal, y lateral and z vertical direction. The variant No 3 is the main variant – the numerical values of the geometric, elastic, inertial and dissipative elements of the variant 3 were finally applied to create the locomotive. Differences between variants 1–3 are associated with design changes and refinement of parameters. The parameters of variants 4–8 were varied, primarily in order to reach an increase in the critical speed. The ninth variant arise in connection with the calculations focused on determining the effect of the primary suspension stiffness on the values of normalized parameters. In order to optimize the parameters of an electric locomotive with the aim of increasing its critical speed, the first stage of the study considered the sensitivity of the critical speed to the changes in the parameters of the system. The influence of the changes of the stiffness of the secondary suspension springs kkx ; kky ; kkz , of values of the axle-box suspension stiffness kbx ; kby ; kbz , of the damping coefficients of the secondary suspension bkx ; bky ; bkz and of the damping coefficients of the primary suspension bbx ; bby ; bbz were investigated. The results of the calculations showed that the critical speed is the most sensitive to the changes of stiffness kbx (Fig. 1), stiffness kby (Fig. 2) and damping bky (Fig. 3) for all investigated variants. It can be seen from the above plots that a decrease in the stiffness values kbx and kby and damping bky leads to the increased values of the critical velocity. The highest values of the critical speed are reached for the variant 6. Since the decrease in stiffness kby can lead to increased lateral displacement of the axle-box relative to the bogie-frame, which will adversely affect the operation of the traction drives, the lateral displacement of the axle-box relative to the bogie-frame Dby in dependence on the running speed were calculated for all variants. Those calculations were done both in the straight (Fig. 4) and in the curved track sections (Fig. 5).

Influence of Parameters of Electric Locomotive on its Critical Speed

Fig. 1. Dependence of the critical speed on of the stiffness kbx .

Fig. 2. Dependence of the critical speed on of the stiffness kby .

Fig. 3. Dependence of the critical speed on of the damping bky .

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Fig. 4. Lateral displacement of the axle-box relative to the bogie-frame Dby in dependence on the running speed – straight track.

Fig. 5. Lateral displacement of the axle-box relative to the bogie-frame Dby in dependence on the running speed – curved track of radius R = 600 m (left), R = 300 m (right).

The calculations showed that the lateral axle-box displacement Dby increases significantly with increasing speed and decreasing stiffness of the connection between wheelset and bogie-frame kby . The lowest values of the Dby were obtained for the variants 1 and 9. In order to determine the optimal values of stiffness kbx and kby , with respect to increased critical speed and not to high values of axle-box displacement Dby , the lines of equal critical speed values were built (Figs. 6, 7 and 8).

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Fig. 6. Lines of equal values of critical speed with respect to stiffness kbx and kby design variant 1.

Fig. 7. Lines of equal values of critical speed with respect to stiffness kbx and kby design variant 3.

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Fig. 8. Lines of equal values of critical speed with respect to stiffness kbx and kby design variant 9.

Variants 1, 3 and 9 have the same values of stiffness kbx ¼ 70 MN=m and kby ¼ 5 MN=m. By the comparison of Figs. 7, 8 and 9 it can be seen that both variants 1 and 9 offer the increase of the critical speed to 170 km/h compared to the base variant 3 with the critical speed of 155 km/h. Moreover, the variant 9 reaches the lowest values of the axle-box displacement Dby (see Figs. 4 and 5).

4 Summary of Results Variation of the parameters showed that the critical speed is the most sensitive to the changes in the values of the longitudinal and lateral stiffness of the axle-box and bogieframe connection. For the values kbx and kby , proposed in variant 5, for example, the critical speed of 200 km/h was reached. However, at the same time the dynamic indicators associated with displacements also increase. The largest horizontal transverse displacement of the axle-box relative to the bogie frame Dby , when the locomotive runs at speed of 100 km/h in a curved track of 600 m radius are 6.2 and 7.2 mm, which are obtained for the variants 5 and 6. These variants are characterized by the low values of the stiffness kby equal to 3,460 respectively 3,000 kN/m. The gradient of the increase of the Dby when reducing the value of kby increases. Considering the conflicting effect of the stiffness kby on the critical speed and displacements Dby it is necessary to find the largest possible value of the stiffness value kby , which still provides the desired value of the critical speed. According the performed calculations, the value of kbx in the range of 4,000–4,200 kN/m and the value of kby in the range of 43,000–50,000 kN/m are recommended. These values correspond to variants 7 and 8 at which the critical velocity of 183 km/h (var. 7) and 176 km/h (var. 8) were reached.

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Given the sensitivity of the critical speed to the value of kby , the primary suspension and the connection of the axle-box and bogie-frame should be thoroughly designed and its components carefully selected according to the stiffness value, avoiding dispersion from nominal values of more than ±15%.

5 Conclusions The critical speed is an important parameter, which often limits the maximum operating speed of a vehicle. An increase in the critical speed can be achieved by tuning the suspension parameters, in particular the stiffness of the connection of axle-boxes and the bogie-frame. The results presented in this paper were obtained by the calculation of eigenvalues of the linear spatial model of the electric locomotive. Another methods of assessing vehicle stability are based on nonlinear models, which more accurately represent the behavior of a real vehicle. This is the direction of the future work of the authors.

References 1. Kortum, W., Goodall, R.M., Hedrick, J.K.: Mechatronics in ground transportation-current trends and future possibilities. Ann. Rev. Control 22, 133–144 (2008) 2. Myamlin, S., Dailydka, S., Neduzha, L.: Mathematical modeling of a cargo locomotive. In: Proceedings of 16th International Conference on “Transport Means 2012”, pp. 310–312 (2012) 3. Myamlin, S., Luchanin, M., Neduzha, L.: Construction analysis of mechanical parts of locomotives. TEKA Comm. Motorization Power Ind. Agric. 13(3), 162–169 (2013) 4. Tatarinova, V.A., Kalivoda, J., Neduzha, L.O.: Research of locomotive mechanics behavior. Sci. Transp. Progress 5(77), 104–114 (2018). https://doi.org/10.15802/stp2018/148026 5. Myamlin, S., Kalivoda, J., Neduzha, L.: Testing of railway vehicles using roller rigs. Procedia Eng. 187, 688–695 (2017). https://doi.org/10.1016/j.proeng.2017.04.439. Proceedings of 10th International Scientific Conference on “Transbaltica 2017” 6. Myamlin, S., Neduzha, L., Urbutis, Ž.: Research of innovations of diesel locomotives and bogies. In: Proceedings of 9th International Scientific Conference on «Transbaltica 2015», vol. 134, pp. 470–475 (2016). https://doi.org/10.1016/j.proeng.2016.01.069 7. Kalivoda, J., Bauer, P.: Roller rig tests with active stabilization of a two-axle bogie. In: CivilComp Proceedings. Railways 2016, The Third International Conference on Railway Technology: Research, Development and Maintenance, Cagliari, 05 April 2016–08 September 2016. Civil-Comp Press Ltd., Stirling (2016). https://doi.org/10.4203/ccp.110.96 8. Vorobiev, V.I., Izmerov, O.V., Kopyilov, S.O.: Features of decision-making simulation when designing locomotive underframe part. In: Proceedings of the 4th International Conference on Industrial Engineering, pp. 2347–2356 (2018) 9. Knothe, K., Böhm, F.: History of stability of railway and road vehicles. Veh. Syst. Dyn. 31 (11), 283–323 (1999) 10. Braghin, F., Bruni, S., Resta, F.: Active yaw damper for the improvement of railway vehicle stability and curving performances: simulations and experimental results. Veh. Syst. Dyn. 44 (5–6), 857–869 (2007)

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11. Polach, O.: Curving and stability optimisation of locomotive bogies using interconnected wheelsets. Veh. Syst. Dyn. 41, 53–62 (2004) 12. Kyryl’chuk, O., Kalivoda, J., Neduzha, L.: High speed stability of a railway vehicle equipped with independently rotating wheels. In: Proceedings of 24th International Conference on Engineering Mechanics 2018, pp. 473–476 (2018). https://doi.org/10. 21495/91-8-473 13. Klimenko, I., Kalivoda, J., Neduzha, L.: Parameter optimization of the locomotive running gear. In: Proceedings of 22nd International Scientific Conference on «Transport Means. 2018», pp. 1095–1098 (2018) 14. Klimenko, I., Černiauskaite, L., Neduzha, L., Ochkasov, O.: Mathematical simulation of spatial oscillations of the “Underframe-Track” system interaction. In: Proceedings of 12th International Conference «Intelligent Technologies in Logistics and Mechatronics Systems – ITELMS 2018», pp. 105–114 (2018) 15. Gorbunov, M., Fomin, O., Kovalenko, V., Domin, R.: Theoretical foundations for conceptually new rolling stock modules. Part 1: monograph. Volodymyr Dahl East Ukrainian National University, Akcept, p. 100 (2017) 16. Dub, M., Kolář, J., Lopot, F.: Axle gearbox hinge as a diagnostic member for rail vehicle drive. In: EAN 2018 56th Conference on Experimental Stress Analysis, Conference Proceedings, pp. 77–83. Česká společnost pro mechaniku, Praha (2018) 17. Dub, M., Kolář, J., Lopot, F., Dynybyl, V.: Dynamic simulation of a driving wheelset on the roller test rig. In: Civil-Comp Proceedings. Railways 2016, The Third International Conference on Railway Technology: Research, Development and Maintenance, Cagliari, 05 April 2016–08 September 2016. Civil-Comp Press Ltd., Stirling (2016). https://doi.org/10. 4203/ccp.110.260 18. Bauer, P., Kalivoda, J.: System of axle-box force measurement for experimental railway bogie. In: Experimental Stress Analysis - 56th International Scientific Conference, EAN 2018, Conference Proceedings, pp. 9–16. Česká společnost pro mechaniku, Praha (2018) 19. Блoxин, E.П., Кopoтeнкo, M.Л., Лyxaнин, H.И.: O кoнcтpyкциoннoй cкopocти лoкoмoтивa. Зaлiзничний тpaнcпopт Укpaїни, vol. 4, pp. 41–42 (2007)

The Environment of Extremist Textual Content Threatening Transportation Systems Olga Zervina(&) Transport and Telecommunication University, Riga, Latvia [email protected]

Abstract. Today, assuring safety and security is a key to developing efficient and safe transportation systems. This paper examines some issues related to transportation security data and determines the place of extremist textual content threatening transportation systems. The author proposes a few schemes describing extremist textual content environment. They demonstrate how different types of transportation offenses such as Environmental crimes, Thefts, Cyber Crimes and Terrorism. Cyber Crimes and Terrorism are linked together and form a vivid symbiosis for terrorist attacks preparation process. Those attacks target public places like airports and stations, online transportation systems and means of transportation. Online extremists’ activities aiming at transportation systems disruption involve online financing, technological support/coordination, online sites provision and extremist textual content. The variety of textual content is not limited by but includes social media, independent publications, emails, and messengers. The paper also examines some obstacles for examining extremists’ textual content. Many countries’ legislation prohibits extremist content and this makes it a challenge to find hidden discussions or even encrypted messages. Keywords: Transportation security Text


Extremist attacks
Unstructured data


1 Introduction Like most other industries, Transportation and logistics (T&L) is currently confronting various threats. Unforeseen events can be a serious reason for disruptions in world trade. It includes geo-physical disasters, terrorism and piracy, civil unrest and geopolitical security. None of these events are absolutely predictable. However, some of these events can be preventable to a certain extent, particularly those where a human factor is involved. An international terrorism is one of them. This industry achieves a special attention in this context, as it is stated in PricewaterhouseCoopers (PwC) review “Transportation and Logistics 2030”: “Logistics, as driver of globalization, will become the focus of offenders in the years to come” [1]. It should be noted that some international organizations such as The International Maritime Organization (IMO), The Customs Cooperation Council (better known as the World Customs Organization (WCO) and The International Chamber of Commerce (ICC) have developed special rules and recommendations as a response to the international terrorism to prevent future attacks. The International Maritime Organization © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 541–551, 2020. https://doi.org/10.1007/978-3-030-38666-5_57

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(IMO) implemented the International Ship and Port Facility Security (ISPS) Code in December of 2004 [2]. This code enhances port security by requiring specific security measures that ports have to put in place, such as controlling access, monitoring activities, and having secure communication systems. The IMO made ISPS part of the International Convention for the Safety of Life at Sea (SOLAS) [3], a convention that had been ratified by many countries. The World Customs Organization (WCO) has traditionally worked towards the simplification and harmonization of Customs procedures [4], but it implemented the SAFE initiative (Security and Facilitation in a Global Environment) [5] in 2005. The SAFE initiative attempts to coordinate the efforts of Customs offices worldwide, and uses the authority of the Customs office in the exporting country to assist the Customs office in the importing country to reduce the terrorism threat [6]. In spite of the endeavors attempted by these organizations, numerous countries have singularly prepared various distinctive initiatives intended to decrease the impact of the terrorism. Those regulations make work of international logisticians more complicated as they have to comply with a myriad of regulations [6]. Most of them, though, comply with the rules that were formulated by the international organizations. The United States government has several programs developed to diminish the threat of terrorism: • Customs-Trade Partnership Against Terrorism (C-TPAT), 2006 [7]. CTPAT is a voluntary public-private sector partnership program which recognizes that CBP (U.S. Customs And Border Protection agency) can provide the highest level of cargo security only through close cooperation with the principle stakeholders of the international supply chain such as importers, carriers, consolidators, licensed customs brokers, and manufacturers. • Importer Security Filing (10+2), 2009 [8]. Importers need to provide U.S. Customs and Border Protection with cargo information (content, exporter, importer, and carrier) at least 24 h before the cargo is loaded onto a ship bound for the United States. Similar requirements exist for air cargo and truck/rail cargo. • Maritime Transportation Security Act (MTSA), 2002 [9]. The Maritime Transportation Security Act of 2002 (MTSA) is designed to protect the nation’s ports and waterways from terrorist attacks. The goal of the MTSA program is to prevent a Maritime Transportation Security Incident – defined as any incident that results in: loss of life, environmental damage, transportation system disruption, or economic disruption to a significant area [9]. EU (European Union) safety agencies deal with the different transport modes – EASA (European Aviation Safety Agency), ERA (European Railway Agency) and EMSA (European Maritime Safety Agency), which are responsible for the aviation, rail and maritime sectors respectively and developed number of regulations, such as: Regulation (EC) No 216/2008 of 20 February 2008 on common rules in the field of civil aviation and establishing a European Aviation Safety Agency, and repealing Council Directive 91/670/EEC, Regulation (EC) No 1592/2002 and Directive 2004/36/EC on aviation safety; Policy orientations on road safety 2011–2020, Valletta Declaration on Road Safety 2017, EU Strategic Action Plan on Road Safety 2018 [10].

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With the Third Maritime Safety Package adopted in 2009, the EU expanded its legislative arsenal covering all chains of responsibility in the maritime sector. The European Commission can rely on the technical and scientific assistance of the European Maritime Safety Agency (EMSA) [11]. The vast majority of extremists’ attacks require special preparation. And it is mostly exclusively a preparation involving cyber-crimes. International organizations aiming at it work to prevent terrorism constantly follow the updated situation. The aim of the article is to analyze the reflection of extremists texts threat in the international transportation security concept. The objectives of the paper are the following: • To analyze the concept of today’s transportation security. • To designate the role of cyber-security as one of the leading in modern transportation security. • To provide research results on the place of extremist texts in the security concept of transport sector. The article is organized as follows: the next section provides methodology of analysis for extremist texts place in the transportation security environment. Then the results of the analysis are presented in three charts. Finally, some concluding remarks are offered.

2 Methodology The following methods and scientific practices were used in the article: 1. 2. 3. 4. 5. 6.

Identifying problems. Developing research objectives. Literature review on the research topic. Qualitative analysis of sources of unstructured data in transportation and logistics. Organizing data into schemes. Describing elements of a system of extremist texts calling for destabilizing actions in transport. 7. Interpreting place of extremist textual content threatening transportation systems. The paper is based on international documents, guidelines and action plans, developed by the European Commission, United States Transportation and Security Agencies and international organizations, operating in the area of transportation and logistics. The approach adopted in this paper is based on the principles of transportation safety and security used by recognized international organizations.

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3 Results 3.1

Transportation as a Target for Extremists

Transportation channels and vehicles are gaining attention of extremists groups because of the large scale of possible casualties. They likewise offer the possibility of transforming transport into weapons, with a critical increment in unfortunate victims (e.g., planes). The trouble of safeguarding the numerous potential targets while keeping up smooth transport tasks and the trouble of forecast the likelihood of a terror activity additionally increment it to terrorists. Also, the necessity of easy access to public transportation constrains the extent of potential security upgrades.

Fig. 1. Transportation Targets Attacked by Terrorists, 1970–2014 [12].

Not every attack on public transportation will amount to a threat to critical infrastructure. Not necessarily attack on public transportation makes a critical damage and leads to multiple victims. However, the Fig. 1 provides a snapshot of the types of transportation most frequently targeted in terrorist attacks. The data of the attacks occurred were collected worldwide. The most frequent targets were buses and trains, which makes 61.6% of all transportation targets worldwide between 1970 and 2014. According to it, airports represented 6.4% of all transportation targets and subway systems made up 1.9% of all transportation targets. The transportation segment is particularly difficult to manage on the grounds as it is usually a mixture of public/commercial establishments. It makes a transport infrastructure even more vulnerable for the attacks [13]. As a crucial element of the urban civilization transportation is presented widely in the everyday life. People use transport on daily basis, they run buses, trains, spend time in airports, cross bridges and almost no one can be excluded from the potential terrorist aims.

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Cyber-Crimes as a Tool for Attacks on the Transportation Infrastructure

Together with transportation systems digital technologies are also one of the bases of today’s society. Moreover, transportation systems rely on information technologies for efficient and proper functioning. As the backbone of globalization, computerization is boosting the inquiries to move people and cargo all over the world. Mounting pressure on transport as economies rapidly develop is leading to new digital safety threats. Digital security influences both public and commercial transport, as well as most other business segments, but it is a very special nature of the danger as transportation, especially public transport, affects enormous number of people in a way no business sector does. Digital security can be characterized as the insurance of PCs (Personal Computers) or IT (Information Technologies) systems from assault, harm or unapproved get to. A deeper and more itemized examination of this incorporates the decrease of risk and helplessness, conceivable discouragement measures, cross-country commitment, occurrence reaction methods and capacities, strength, recuperation strategies and exercises. On a more extensive point of view, it incorporates digital organized tasks, data confirmation, law requirements, discretion, military and insight missions, as they all are identified with the security and globosity of worldwide data [14]. According to the Global Agenda Council on Cyber-Security, 2016 among the many significant challenges that can make it difficult for the public sector to effectively address cybersecurity issues, there are three particularly important hurdles: 1. International fragmentation: differences in approaches to cybersecurity, data jurisdiction and legal enforcement (not to mention culture, language and politics) across jurisdictional and territorial boundaries can make it hard to effectively prevent, investigate and prosecute cyberattacks. 2. International norm-setting: international political differences and country-specific agendas can make it difficult to develop consensus norms regarding cybersecurity let alone enforce those norms consistently and effectively. 3. Roles with respect to the private sector: the varying and sometimes confrontational roles that the public sector must play, spanning regulator to information sharer and collaborator, can create tensions with the private sector that can be counterproductive to trust and cooperation [13]. According to the European Commission Key Figures, 2017 [15], despite the growing threat, awareness and knowledge of cybersecurity is still insufficient: • 51% of European citizens feel uninformed on cyber threats; • 69% of companies have basic or no understanding of their exposure to cyber risks. Cybersecurity threats: • Ransomware attacks have increased threefold between 2015 and 2017; • The economic impact of cyber-crime rose fivefold since 2013; • 87% of Europeans see cyber-crime as an important challenge for EU’s internal security.

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On 24 October 2017, the Telecommunications Council agreed to set up an action plan for the reform of EU cybersecurity. On 13 September 2018, the Council started negotiations with the European Parliament with a view to reach an agreement on the so-called Cybersecurity Act. On 19 December 2018, EU ambassadors approved the proposed Cybersecurity Act. This will enable the introduction of an EU-wide cybersecurity certification and will also lead to the consolidation of a permanent EU Agency for Cybersecurity [16]. Suggested as a segment of a wide-running arrangement of measures to manage cyberattacks and to advance improved digital security in the European Union together with the Network and Information Security “NIS” Directive and a fortified spotlight on safety efforts in the General Data Protection Regulation, the Act aim is, as per the EU organizations, to assume an imperative job in dealing with those challenges. It will help setting EU cybersecurity accreditation plans for ICT items (i.e., equipment and programming components of system and data frameworks); administrations, for example, administrations engaged with transmitting, putting away, recovering or preparing data through system and data frameworks. As well as it will lead to manifest procedures like sets of exercises performed to configuration, creation, conveying and keeping up ICT items or administrations. The European Union Agency for Network (ENISA) and Information Security will be entrusted to get ready hopeful plans for explicit gatherings of ICT items, and procedures for appropriation by the European Commission [17]. 3.3

Place and Reflection of Extremist Texts in the Concept of Modern Transportation Security

One of the ways to prevent attacks on transportation is to study and clear potential extremists having access to their written texts. This problem is on the edge of several disciplines: linguistics, information technologies and logistics. Potential extremists could be inside the transport system or could be outside. History of violent attacks knows many examples of workers whose job role was to provide security turned to use their positions against humanity and people’s safety. In the investigation following the London Bridge attack 2017, it was emerged that Khurram Butt, one of the three killers, had previously worked for London Underground [18]. On 29 January 2016 Reuters reported on investigation of Russian plane Metrojet in Egypt (2015); a mechanic had been detained and was suspected of planting a bomb, which he had been given by his cousin, who was a member of ISIS. Two policemen and a baggage-handler were suspected of helping the mechanic [19]. Malaysian Airways lost its MH370 flight in 2014. Police investigation names MH370 pilot “prime suspect”, Australian News reported [20]. To show the place, types and access for unstructured transportation data, this paper offers Fig. 2. Figure 2 is developed based on analysis of structured and unstructured data sources in transportation field used by the author. The scheme shows five major transport threats that could be reflected in the unstructured security data: Corruption, Civil and Geopolitical Security, Technological and Natural Disasters, Terrorism and Piracy, Cargo Crimes. The texts are in the forms of work reports, government reports and unobserved narrations. For text analytics there is a limited access to federal

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investigation reports, police reports, official letters, in company descriptions and complains. The open source for involved analytics could be email letter and instant messengers. The most accessible and easy to analyze text sources are narrations posted in social media and independent publications.

Fig. 2. Transportation security data sources (source: constructed by the author).

Extremists could perform in organized groups or could be sole actors. Nevertheless, the communication, active or in read-only mode, makes them members of the circle of violent activity. To show the link between Cyber-crimes and terrorism on transportation and place of extremist textual content this paper offers the following Fig. 3. Figure 3 is developed by the author based on analysis of transportation offences and types of cyber-crimes in transportation field. Terrorists’ communication strategy involves a noteworthy violent act, or threat thereof, that secondarily communicates with multiple audience groups. One audience may be supporters of the terror group who construct identity from the violent act as well as from grievances that the group seeks to advertise. Another may be outgroups sympathetic with the substance of communicated messages. Still another may be foreign countries, which may provide a sense of legitimacy to the actions of the group [21]. Communication may influence and radicalize those who were not extremist minded or even opportunistic readers. Even involvement into a group work with claimed noble goals could attract those who firstly acts as an online communicator only.

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Fig. 3. Place of extremist textual content threatening transportation systems (source: constructed by the author).

Group identity is fundamental to the formation, recruitment, and functioning of terrorist organizations, as it dictates how communicative messages are framed by the group and received by the audience [22]. Media produced by terrorist organizations defines and reinforces group identity in a number of ways, including identifying the group’s enemies and demonstrating the necessity and desirability of conflict [23]. A perception of group-based victimization or relative deprivation can trigger outgroup hostility and in group cohesion [24]. To communicate online and achieve their goals extremists write texts. The author proposes a chart for elements of a system of extremist texts calling for destabilizing actions in transport (see Fig. 4). As seen from Fig. 4, major elements of a system of extremist texts are writing actors, their goals and forms. Writing actors are as follows: 1. Extremists: Ideologists, Sponsors, Performers and Sympathizers. 2. Provokers: Internet Trolls and Security Services. 3. Opponents: Contradictors and Security Services. The goals of extremist texts calling for destabilizing actions on transport are the following: 1. To provoke on extremist actions and sayings. 2. Emotional sayings: calls for actions and judging. 3. To contradict the ideas: to criticize and to calm down.

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Fig. 4. Elements of a system of extremist texts calling for destabilizing actions in transport (source: constructed by the author).

The major forms of online texts are as follows: 1. 2. 3. 4.

Forums. Social Media. Specialized Online Editions. Blogs.

4 Conclusions In this paper, the author has analyzed the reflection of extremist texts threat in the international transportation security environment. The author has made the following conclusions based on the analysis performed in the paper: 1. The concept of today’s transportation security has been revised. The vivid trend shows that leading world nations are constantly accepting new initiatives in the sphere of transportation security. Their concern is determined by increasing number of attacks on transport. 2. The paper has designated the role of cyber-security as one of the leading in modern transportation security. This conclusion is made based on trends reflected in documents adopted in the recent years by leading international organizations such as: Global Agenda Council on Cyber-Security 2016, European Commission Key Figures 2017, and EU Cybersecurity Act 2018.

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3. The paper has provided research results on the place of extremist texts in the security concept of transport sector. 4. Three schemes have been proposed: transportation security data disposition, place of extremist textual content threatening transportation system and elements of a system of extremist texts calling for destabilizing actions in transport. 5. The research results suggest that one of the methods to increase cybersecurity is finding online extremist texts for their further analysis; in the process, a set of special text analysis techniques is to be used.

References 1. RwC Report: Transportation & Logistics 2030. https://www.pwc.com/gx/en/transportationlogistics/pdf/tl2030_vol.4_web.pdf. Accessed 27 Jan 2019 2. International Ship and Port Facility Security (ISPS) Code. http://www.imo.org/en/OurWork/ Security/Guide_to_Maritime_Security/Pages/Default.aspx. Accessed 27 Jan 2019 3. International Convention for the Safety of Life at Sea (SOLAS). http://www.imo.org/en/ about/conventions/listofconventions/pages/international-convention-for-the-safety-of-life-atsea-(solas),-1974.aspx. Accessed 27 Jan 2019 4. The Revised Kyoto Convention. http://wcoomd.org/en/topics/facilitation/instrument-andtools/conventions/pf_revised_kyoto_conv.aspx. Accessed 27 Jan 2019 5. SAFE Initiative (Security and Facilitation in a Global Environment). http://www.wcoomd. org/-/media/wco/public/global/pdf/topics/facilitation/instruments-and-tools/tools/safepackage/safe-framework-of-standards.pdf?la=en. Accessed 27 Jan 2019 6. David, P.: International Logistics: The Management of International Trade Operations. Cengage Learning, Boston (2014) 7. Customs-Trade Partnership Against Terrorism (C-TPAT). https://www.cbp.gov/bordersecurity/ports-entry/cargo-security/ctpat. Accessed 27 Jan 2019 8. Importer Security Filing (10+2). https://www.cbp.gov/sites/default/files/documents/import_ sf_carry_3.pdf. Accessed 27 Jan 2019 9. Maritime Transportation Security Act (MTSA). https://www.congress.gov/107/plaws/ publ295/PLAW-107publ295.pdf. Accessed 27 Jan 2019 10. European Aviation Safety Agency. https://etsc.eu/. Accessed 27 Jan 2019 11. European Maritime Safety Agency (EMSA). https://ec.europa.eu/transport/modes/maritime/ emsa/emsa_es. Accessed 27 Jan 2019 12. Terrorism in Belgium and Western Europe; Attacks against Transportation Targets; Coordinated Terrorist Attacks. https://www.start.umd.edu/pubs/START_ BelgiumTransportationCoordinatedAttacks_BackgroundReport_March2016.pdf. Accessed 27 Jan 2019 13. Global Agenda Council on Cybersecurity. http://www3.weforum.org/docs/GAC16_ Cybersecurity_WhitePaper_.pdf. Accessed 27 Jan 2019 14. Cyber security in the public sector – the big unknown!?: https://www.intelligenttransport. com/transport-articles/17693/cyber-security-the-big-unknown/. Accessed 27 Jan 2019 15. Key figures on Europe. https://ec.europa.eu/eurostat/documents/3217494/8309812/KS-EI17-001-EN-N.pdf/b7df53f5-4faf-48a6-aca1-c650d40c9239. Accessed 27 Jan 2019 16. Reform of cybersecurity in Europe. https://www.consilium.europa.eu/en/policies/cybersecurity/. Accessed 27 Jan 2019

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17. European Union: The EU Cybersecurity Act Is (Almost) There. http://www.mondaq.com/uk/ x/764664/Security/The+EU+Cybersecurity+Act+Is+Almost+There. Accessed 27 Jan 2019 18. Attacker named as Khuram Butt. BBC. https://www.bbc.com/news/live/uk-40147014. Accessed 27 Jan 2019 19. Exclusive: EgyptAir mechanic suspected in Russian plane crash. Reuters UK. https://uk. reuters.com/article/us-egypt-crash-suspects-idUKKCN0V712V. Accessed 27 Jan 2019 20. Malaysian police investigation names MH370 pilot ‘prime suspect’. https://www.news.com. au/travel/travel-updates/incidents/malaysian-police-investigation-names-mh370-pilot-primesuspect/news-story/db64b7716263e19bab93bd70b79f47e3. Accessed 27 Jan 2019 21. Terrorism as an Evolving Concept. http://oxfordre.com/communication/view/10.1093/ acrefore/9780190228613.001.0001/acrefore-9780190228613-e-409. Accessed 27 Jan 2019 22. Weisel, O., Zultan, R.: Social motives in intergroup conflict: group identity and perceived target of threat. Eur. Econ. Rev. 90, 122–133 (2016)

Decision-Support Framework for the Urban Public Transport System Sustainable Planning: Riga Case Study Irina Yatskiv (Jackiva)1(&) and Evelina Budilovich (Budiloviča)1,2 1

2

Transport and Telecommunication Institute, 1019 Riga, Latvia [email protected] Riga City Council Development Department, 1050 Riga, Latvia

Abstract. The primary contribution of this research is the theoretical development of a decision-support framework that identifies the tools and approaches that decision-makers could/should use to create policies and programs that transition society towards sustainability. The framework is then used to consider how Riga municipality might move the city’s transportation system towards sustainability and particular aspect – to planning decisions for passenger network in Riga City in the frame of Rail Baltica project – Riga central multimodal public transportation hub. Multi-modal transportation planning should have integrated institutions, networks, stations, user information, and fare payment systems it needs to consider all significant impacts, including long-term, indirect and non-market impacts such as equity and land use changes. One of the key-stone questions in this case study - multi-modal transportation planning requires consideration of the factors that affect accessibility and whether they are currently considered in planning? Keywords: Public transport system


Planning
Sustainable indicators

1 Introduction By 2050, 70% of the total population will live in cities. Now, in Latvia (2019), 68.3% of the population lives in urban areas. This growing mobility demand congests the road network, causing long delays, excess fuel consumption, increased pollutants’ emissions (i.e. carbon dioxide), and road safety level deterioration. Therefore, we need to think about sustainable planning and development of cities. Development and planning are the main components of city life. To ensure urban life is necessary to use and apply the principles of sustainable planning. Sustainability is often used as a short form for sustainable development is a harmonious interconnection of all city systems, such as economic, environment and transport, in which the residents of the city are comfortable, safe and convenient to exist or move in the urban area. One of the main aspects for the sustainable development analysis is that decrease the number of public transport users. Also, the population ageing increase, at that moment in Latvia 22.2% of the state inhabitant are in the “Overworking age”. Moreover, the word tendency is that it will be grown up. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 552–561, 2020. https://doi.org/10.1007/978-3-030-38666-5_58

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The main idea of sustainable development is the capacity to meet ‘the needs of today’s citizens without the ability of future generations to meet their need’ [1]. Following this definition, attention is paid to the concept of fairness between current and future generations, where sustainability is looked at from a threefold perspective: economic, social, and environmental. The goal of the research is to identify the gaps between theory and practices that exist in moving the urban public transport system (UPTS) towards sustainable development to propose the decision support framework in comparing with current transportation planning and decision-making processes in Riga city. As defined in Sustainable development strategy of Riga (SDSR) until 2030 [2] one of the main purposes is to improve the urban transport system (UTS), and the vital public transport infrastructure element will be the Riga Central Railway Station (RCRS), which will provide multimodal functions. The primary contribution of this research is the development of a decision-support framework that identifies the tools and approaches that decision-makers could/should use to create policies and programs that transition society towards sustainability. The structure of the paper is the follows: in Sect. 2, main aspects of the sustainable transportation system and measures are presented. The suggested decision-making framework is in Sect. 3 and the description of this framework application to Riga transport system – in Sect. 4.

2 Sustainable Transportation System: Definition, Objectives and Measures The sustainability is a careful balance between social, economic and environmental goals (often referred to as the “three pillars”). The sustainable transportation system (STS) development starts with the public space organisation. The primary objective is to reduce the demand for transportation according to the number of trips and the length of travel distance. As noted by the United Nations Economic and Social Commission (UN ESCAP) [3] the organisation of urban space helps to minimise the distances that people are travelling to obtain goods and services. As mentioned in [3], the STS also requires the provision of a different, integrated and balanced public transportation services. The different groups of passengers have different transportation needs depending on the distances they need to travel, their trip purpose, income, age, gender and physical ability. The significant benefits of the STS are to optimise the use of scarce resources, reducing traffic congestion and air pollution (that is achieved by promoting fuelefficient and green vehicles, car sharing, and encouraging the use of non-motorized transportation). Everyone needs to have access to affordable transportation for improving health, to get an education and social empowerment. It is a mode that everyone can get to work at a place of people choices. The STS may also work as a catalyst in the development process. As defined in [3], a city with the STS can easily attract new businesses and other activities.

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The theme of STS is researched in the scientific field. The researches [4–10] others includes the theoretical studies in the area of Sustainable transportation. There are many definitions of STS, but all say that sustainable transport should be environmentally friendly, affordable, and safe and consider the needs of the population, the direct users of transport. The STS theme is central in many European and international projects: TRUST [11], BEST [12], SEGMENT [13], STELLA [14], ENDURANCE [15], SUMBA [16] and others. The United Nations Economic and Social Commission [3] defines the objectives and measures for STS that are represented in Table 1. Table 1. STS objectives and measures [3]. STS the primary objectives Reduce the travel demand, mainly by motorised modes by reducing the number of trips and trip lengths Greater use of genuinely sustainable modes (i.e. walking and other non-motorized transport) Efficient use of existing systems and reducing the use of all resources – natural, physical and financial Increasing energy efficiency and emission standards of motorised vehicles

STS measures The organisation of urban space – land use planning and finding a better solution to meet the needs through action in other areas Making services and opportunities accessible by walking and non-motorized transport Development of a balanced, integrated transport system that ensures efficient travel using multiple modes Technological standards (vehicle, fuel, emission etc.) Improvement in the efficiency of urban freight logistics through the organisation of freight distribution and delivery facilities and services

Sdoukopoulos et al. in [17] calculated and consolidated the sustainable transport indicators (together 47) and it is considered in Table 2. The indicators are divided by three sustainability pillars: the Environment is represented by 15 indicators, Society – 8 indicators and Economy – 7 indicators. However, nine indicators included in all spheres such as Urban planning and land-uses, Integrated planning, Non-motorised modes, Mobility, Public transport, Infrastructure, Multimodality, Transport external costs and Parking — liveable public space and amenities and Fragmentation involved in Society and Environment. Society and Environment bring together such indicators as Demographics and socio-economic characteristics, Affordability, Commuting, Traffic congestion. Also, Economy and Environment combined the New smart and green technologies and Vehicles fleet. In [17] suggested that the environment includes a slightly higher number of indicators as a society and far larger when it is compared to the economy. Moreover, according to Table 2, 30 out of the 47 themes (63.8%) are related to one of the three pillars, while the rest 36.2% either refers to two pillars (8 themes) or mutually corresponds to society, environment and economy (9 themes). It was fulfilled the current situation analysis of Riga Transport System by Latvian experts; the indicators were ranked. The results in Table 2 represent that, by experts suggestion and ten indicators ranking scores, the problems are in all sectors: Environment, Society and Economics.

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Table 2. The ST indicators [17] adopted by the authors. Sustainable transportation Indicators Health impacts Cultural aspects Trips to/from school Accessibility Safety Security Active citizens Social equity Economic productivity Contribution to economy & development Freight transport Transport efficiency Public expenditures, investments and subsidies in TS Institutional aspects Transport cost and prices Air pollutant emissions Air quality Water Run-off Energy efficiency GHG emissions Fossil fuel energy consumption Impacts to sites of historical and architectural importance Renewable and alternative fuels Impacts on habitats Waste Traffic noise Resource use Land consumption Recycling Hazardous materials and environmental damages Liveable public space and amenities Fragmentation New, smart, green technologies Vehicles fleet Traffic congestion Commuting Affordability

Ranking for Environment Society Economic Riga x 21 x 20 x 22 x 10 x 11 x 12 x 32 x 35 x 44 x 33 x 13 x 14 x 24 x x x x x x x x x

43 15 1 2 45 23 42 41 3

x x x x x x x x

40 39 36 4 30 24 47 25

x x x x

x x

x x x

x x x x x

37 16 46 29 17 26 28 (continued)

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Sustainable transportation Indicators Demographic and socio-economic characteristics Non-motorised modes Urban planning and land-use Integrated planning Mobility Public transport Infrastructure Parking Multimodality Transport external costs

Ranking for Riga Environment Society Economic x x 6 x x x x x x x x x

x x x x x x x x x

x x x x x x x x x

38 7 5 9 31 8 27 19 18

3 A Decision-Support Framework for UPTS Planning The central research goal is to prepare the methodology of the new Hub development and analyse how the new object will effect to the urban transport system. Figure 1 represents the developed decision-support framework that includes a holistic approach to analyse all aspects of sustainable transportation. A decision-support framework can identify the approaches and tools that decision-makers should use for creating policy and programs that move urban transport city towards sustainability. Planning or changing something in the urban system (creation of a new infrastructure facility), it is necessary to evaluate the impact of these changes, not generally, but in the context of each transport system by system analysis it needs to pay attention to next question: Are strategic transportation project activities sufficient to maintain or improve the current quality levels in the long-term? Multi-modal transportation planning should have integrated institutions, networks, stations, user information, and fare payment systems it needs to consider all significant impacts, including long-term, indirect and non-market impacts such as equity and land use changes. One of the key-stone question in this study - multi-modal transportation planning requires consideration of the factors that affect accessibility and whether they are currently considered in planning? As known, the interchange is one of the important parts of UTS and the keystone in multimodality supporting. That is why the central role of the framework for the decisionmaking process development is the interchange. To the interchange development influence the different kind of spatial rules and regulations, such as national, regional and local levels. Many aspects implement to the interchange development or reconstruction, such as location, design the interchange, design the surrounding areas, etc. How to comprehensively analyse indicators affecting the quality of services provided by the interchange, should be analysed based on the suggested framework and the example of one of the main interchange of the Riga city – RICT. The question is – should spatial and transport planning be better coordinated to match transport demand to access needs?

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For the analysis of the new HUB development, the procedure of the impact analysis was implemented and the sustainable indicator was defined in experts’ survey. Yatskiv and Budilovich in [18] have analysed the leading sustainability indicators which are significant for the Riga Transport System (RTS) and by the questionnaire have concluded that the accessibility is most important for the last one. Therefore, the main aspects that should be analysed in decision making at the stage of new passenger HUB planning are measures of accessibility before and after reconstruction. Using the before-and-after analysis of RTS accessibility helps to identify how the HUB needs to be improved or where it is required to promote the public transport network based on the criteria of accessibility measurement. So, the Fig. 1 represents a decision-support framework for the urban public transport system sustainable planning and transport terminal accessibility analysis that incorporates the objectives of sustainable development.

Fig. 1. A decision-support framework for the urban public transport system sustainable planning and transport terminal accessibility analysis. Framework Application for Riga Transport System.

The framework is used to consider how Riga municipality might move the city’s transportation system towards sustainability and particular aspect – to planning decisions for passenger network in Riga City in the frame of Rail Baltica project – Riga central multimodal public transportation hub. The activities provided for holistic analysis of interchange (RICT) is presented in Fig. 2. To consider the geographical position of the Riga city, that presents a interchange in all transport networks from regional to the interstate, special attention should be paid to the integration of various trips in every way promoting multimodality.

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Fig. 2. The activities prepared/provided for RICT analysis in the frame of decision-support framework planning.

Firstly, before the accessibility and interchange analysis, need to understand how the unknown factors, such as mobility demand, can influence to the TS. It can be analysed based on different kinds of surveys and it needs to provide at least, the traveler satisfaction survey and the stakeholder satisfaction survey. The following activities for analysis the current situation of RICT were done: 1. RICT stakeholders’ definition. 2. RICT accessibility analysis for the long-distance intermodal trip. The analysis focused the multimodal trip structure for international, regional and urban trips for Riga UTS and on analysis accessibility taking into account the time distribution between intercity part of the trip and intracity (Riga city) part [19]. 3. Analysis of RICT service quality: • the survey of traveller satisfaction and a multiple regression analysis was conducted to examine the effect of selected factors (indicators) on the general satisfaction level of travelers [20];

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• quality indicator benchmarking (based on decision tree: a decision tree was used to model how the performance evaluation of the selected indicators affects the overall satisfaction level of the terminal) [21]; • stakeholder satisfaction survey and gap analysis provided on users/stakeholders satisfaction; • interchange accessibility level evaluation on the basis of selected measures: the impedance; the interconnectivity ratio and closeness centrality; These measures were evaluated on the basis of macroscopic simulation, that also provided local regulations for accessibility analysis and interchange development. 4. Meta-analysis of interchanges: RICT and EU interchanges (Best Practices). 5. Analysis of information services implementation in the RICT. For RICT accessibility and the surveys results’ analysis helps to define the important problems, for instance, one of the most significant - lack of information integration for ticketing in case of multimodal trip. This framework is useful in process of the SUMP implementation and preparation. It provides a tool for analysis the feasibility and a methodological guide for implementing measures towards multimodal passenger interchange service improvement and assess the stakeholder’s role in urban transportation and develop a comprehensive set of actions that the municipality should use to promote a sustainable transportation system.

4 Conclusions One of the Sustainable transportation goals that being defined by the Europe Union is to increase the citizen’s mobility regarding multimodality. In terms of multimodality, special importance is attached to the services provided by the terminal (interchange). In paper decision-support framework of transport terminal accessibility analysis that incorporates the objectives of sustainable development is proposed. In Latvia, until now, have not that engaged in the study of transport hubs in terms of accessibility. The ranking of STS for Riga UTS (Table 2) and list of activities for framework implementation for Riga UTS (Fig. 2) are presented. The developed framework is universal and can be adapted for a different kind of interchange in the different size of cities, considering local requirements. The using of framework helps authorities to structure the opportunities and to define the TS system gaps and after, solve them. Acknowledgements. This paper is based on the research and work that has been conducted in the framework of the SUMBA project (http://sumba.eu/), which has received funding from the European Union Interreg Baltic Sea Region Cross Border Cooperation Programme “Sustainable Urban Mobility and Commuting in Baltic States – SUMBA” (PVS ID 3673). The authors would like to thank both the consortium of the project and the European Commission.

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References 1. UNWC, Report of the World Commission on Environment and Development: Our Common Future. Oxford University Press, Oxford (1987). http://www.un-documents.net/ourcommon-future.pdf 2. Strategy, Riga Sustainable development strategy of Riga until 2030. Riga city development department, Rīga (2014). http://www.rdpad.lv/strategija/ 3. UN ESCAP, Sustainable Urban Transportation Systems, United Nations Economic and Social Commission for Asia and the Pacific (UNESCAP) (2012). https://www.uncclearn.org/ sites/default/files/inventory/unescap20_0.pdf 4. Jeon, C., Amekudzi, A.: Addressing sustainability in transportation systems: definitions. Indic. Metrics 11, 31–50 (2005) 5. Boschmanna, E.E., Kwana, M.P.: Toward socially sustainable urban transportation: progress and potentials. Int. J. Sustain. Transp. 2(3), 138–157 (2008) 6. Enoch, M.P.: Sustainable Transport, Mobility Management and Travel Plans, 1st edn. Ashgate Press, Routledge (2012) 7. Maya, A.D.: Urban transport and sustainability: the key challenges. Int. J. Sustain. Transp. 7 (3), 170–185 (2013) 8. Lama, W.H.K., Sumaleea, A.: Introduction: modeling for sustainable urban transportation. Int. J. Sustain. Transp. 7(3), 167–169 (2013) 9. Gössling, S.: Planning sustainable transport, by Barry Hutton. J. Sustain. Tourism 22(8), 1268–1269 (2014) 10. Lia, Z.-C., Lia, Z.-K., Lambc, W.H.K.: An integrated design of sustainable land use and transportation system with uncertainty in future population. Transportmetrica A: Transp. Sci. 10(2), 160–185 (2014) 11. ETF, TRUST: Trade Union Vision on Sustainable Transport, European Transport Workers’ Federation: EU, (2006–2008) 12. EC, BEST: Benchmarking European Sustainable Transport, European Commission: Benchmarking European Sustainable Transport: European Commission: DirectorateGeneral for Energy and Transport (2000–2003) 13. Intelligent Energy Europe, SEGmented Marketing for ENergy efficient Transport: Intelligent Energy Europe, EU (2010–2013). https://ec.europa.eu/energy/intelligent/projects/en/ projects/segment 14. EC, Sustainable Transport in Europe and Links and Liaisons with America, European Commission (2001–2005). https://trimis.ec.europa.eu/project/sustainable-transport-europeand-links-and-liaisons-america 15. Endurance, Project Endurance, EU (2015). http://epomm.eu/endurance/index.php?id=2795 16. Sumba, Sustainable Urban Mobility and Commuting in Baltic Cities, EU (2017). http:// sumba.eu 17. Sdoukopoulos, A., et al.: Measuring progress towards transport sustainability through indicators: analysis and metrics of the main indicator initiatives. Transp. Res. Part D 67 (2019), 316–333 (2019) 18. Yatskiv (Jackiva), I., Budilovich (Budiloviča), E.: Evaluating Riga transport system accessibility. In: 16th Conference on Reliability and Statistics in Transportation and Communication, RelStat 2016, Procedia Engineering (2017). ISSN 1877-7058

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19. Yatskiv (Jackiva), I., Budilovich (Budiloviča), E., Gromule, V.: Accessibility to Riga public transport services for transit passengers. In: 10th International Scientific Conference Transbaltica 2017: Transportation Science and Technology, Vilnius (2017) 20. Tsami, M., Budilovich (Budiloviča), E., Magginas, V., Adamos, G., Yatskiv (Jackiva), I.: Assessing the design and operation of Riga’s international coach terminal, Riga, Latvia. In: Kabashkin, I., Yatskiv, I., Prentkovskis, O. (eds.) Reliability and Statistics in Transportation and Communication, RelStat 2017. Lecture Notes in Networks and Systems, vol. 36, pp. 497–506. Springer (2018) 21. Tsami, M., Adamos, G., Nathanail, E., Budilovich (Budiloviča), E., Yatskiv (Jackiva), I., Magginas, V.: A decision tree approach for achieving high customer satisfaction at urban interchanges. J. Transp. Telecommun. 19(3), 194–202 (2018)

Study of Field Testing on Car Body Vibrations of Moving Passenger Car with Wheel Flat Stasys Steišūnas1(&), Gintautas Bureika1, Olha Porkuian2, and Volodymyr Nozhenko2 1

Vilnius Gediminas Technical University, Saulėtekio al. 11, 10223 Vilnius, Lithuania {stasys.steisunas,gintautas.bureika}@vgtu.lt 2 Volodymyr Dahl East Ukrainian National University, Tsentralnyi pr. 59-a, 93400 Severodonetsk, Ukraine [email protected], [email protected]

Abstract. The article analyze the methodology of experimental investigations of railway vehicles under real operating conditions. The aim of the research is to determine the vertical and lateral accelerations of the carbody of passenger car with a wheel flat by running along the same track at different speeds. Statistical analysis of the obtained data was performed. Experimental results were evaluated using shock acceleration ratio and Sperling ride index was calculated. General conclusions are given. Keywords: Railway transport
Passenger car
Wheel flat vibration
Sperling index
Shock acceleration ratio


Car body

1 Introduction When a train moves on rails, natural fluctuations in the rolling stock occur, while forced fluctuations in the rolling stock appear due to uneven track. If defects appear on the rolling surface of the wheel during the interaction of the wheel with the rail, dynamic forces act that create additional load on the rail and wheel. Due to the vibration of the rolling stock caused by these forces, a traffic accident, noise and a negative effect on passenger comfort during movement can occur [1]. While vehicles are running on rails, these defects of the rail vehicle and track create additional body vibrations and noise that can cause discomfort for passengers [2]. Wheel flat is the most common wheel damage caused by wheel slip or jammed brake pads [3]. The larger dynamic forces at higher speed of vehicles have an impact on spreading of damages. Improper wheel shape or incorrect installation of wheel or brake discs can have an impact on rolling stock movement [4], Morys [5] and other scientists [6, 7] have examined the influence of wheel surface geometry changes. Vertical mutual interaction of damaged wheel and track contact have shock nature. The specific methods are required for these studies, since the examined processes are of higher frequency (up to 20 kHz). Respectively, the maximum force durations last several milliseconds depending on train travelling speed [8]. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 562–571, 2020. https://doi.org/10.1007/978-3-030-38666-5_59

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2 Vibration Assessment Criteria and Permissible Vibration Parameters The recurrence of car body oscillations is called car body vibration and can affect the comfort of passenger cars negatively. Vibrations worsen the well-being of passengers and reduce the working capacity of passenger service staff. Therefore, it is necessary to assess the vibration intensity considering its harmful impact to human. During the reduction of general vibration level, it is necessary to take into account the vibration frequencies, since some vibration frequencies are harmful to human body. The impact of vibration and noise on the passenger determines his/her travel comfort described by the entire set of parameters – vibration frequency and amplitude, noise level, air humidity and temperature, etc. [9]. During the assessment of vehicle vibration level and taking into account the passenger comfort, Sperling smooth running indicator can be used [10]: WZ ¼

nf X

!101 WZ10i

1 h i6:67 ; where Wzi ¼ a2i Bðfi Þ2

ð1Þ

i¼1

where a – acceleration, cm/s2, f – vibration frequency, Hz, o B(f) – frequency and vibration direction coefficient influencing the passenger’s well-being: sffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi 1:911f 2 þ ð0:25f 2 Þ2 Bðf Þ ¼ k ; ð1  0:277f 2 Þ2 þ ð1:563f  0:0368f 3 Þ2

ð2Þ

where k = 0.737, if oscillations are horizontal, and 0.588 if oscillations are vertical. The smooth running indicators calculated based on (1)–(2) are compared with standard assessment scale. The quality of vehicle carrier is finally assessed according to comparative results. Vibration has a negative impact on human hearing, vision, circulatory, nerve system, as well as brain activity. The effect on human also depends on vibration duration. The longer it lasts, the more the physiological functions of the body are damaged. In addition, the longer the vibration duration, the more time the body needs to recover to normal condition. It can be concluded that the most harmful frequencies for the human body are at range of 4–8 Hz. In order to ensure the necessary comfort in passenger cars, the smooth running coefficient must be WZ = 2.0–2.5 [10, 11]. Therefore, after having summarised the vibration impact to human body, i.e. to human health and comfortable feelings in a vehicle, it can be stated that vibration is the most difficult to control and its permissible rates can be hardly reached in vehicles. It depends not only on the design of vehicles, but on track condition also. The latter is the main stimulator of oscillations. In order the smooth running coefficient not to exceed the permissible WZ, the respective studies of passenger cars with permissible wheel damages are necessary.

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3 Methodology of Experimental Investigations of Passenger Car In the course of the tests, the following indicators of the car bodywork were studied: vertical, lateral and longitudinal accelerations. Tests are carried out in the range of speeds of rail vehicle from 30 km/h to 80 km/h. Speed was changed by every 10 km/h. 12 tests were performed at each speed. The speed of the test vehicle was determined with an error of less than 5%. The damage of first wheelset was a flat of 1 mm in depth and 20 mm in length. The diameter of damaged wheelset was 901 mm. Indicators were measured in the “Joniskis - State Border” section or railway. The ideal quality of the track was determined by the measurements taken. The data of all sensors were collected synchronously using Corrsys-Datron and KISTLER equipment (Fig. 1b, c) mounted on the pivot of a passenger car (Fig. 1a). During the study, a recording frequency of 200 Hz was used.

Fig. 1. Experimental investigations of passenger car: (a) experimental train; (b) equipment of data collection Corrsys-Datron DAS-3; (c) accelerometer KISTLER Type 8395A.

The equipment of data collection was installed in carbody of rail vehicle.

4 The Results of Field Testing of Passenger Car Body Vibrations The data collected during experiment have been recorded in to file and later processed by Fourier transform. The results of these calculations are provided in below graphs of Figs. 2 and 3 that shows the dependence of relevant vertical and lateral acceleration amplitude frequencies on running speed.

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Fig. 2. The spectra of vertical accelerations (from 0 to 100 Hz), when vehicle speed is changing: (a) 30 km/h; (b) 40 km/h; (c) 50 km/h; (d) 60 km/h; (e) 70 km/h; (f) 80 km/h.

The graphs of Figs. 2 and 3 shows that acceleration change intensity reaches its highest values at 40 km/h speed low frequency oscillations that have the biggest impact on travel comfort. These oscillations take place at 2 Hz range and their frequency remains practically unchanged at higher speed, thus it can be concluded that these are own oscillations of amortized masses. The largest intensity of vertical acceleration change is reached at 60–70 Hz range. At higher speeds of 70–80 km/h, strong vibrations are observed in the range of 10–20 Hz which cause headaches and eye fatigue of passengers. This is influenced by the construction of the wagons (stiffness and damping coefficients), track and rail profile, track irregularities and running speeds. The root mean square (RMS) values of vibration acceleration and impact factor were calculated, as well as the maximum accelerations at various travel speeds were established in order to assess the impact of vehicle body vibration to passenger travel comfort more precisely and determine the influence of travel speed.

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Fig. 3. The spectra of lateral accelerations (from 0 to 40 Hz), when vehicle speed is changing: (a) 30 km/h; (b) 40 km/h; (c) 50 km/h; (d) 60 km/h; (e) 70 km/h; (f) 80 km/h.

The dependences of carbody vertical and lateral accelerations RMS on the passenger car running speed, are provided in Figs. 4 and 5. The graph 5 shows that the largest RMS values of acceleration are reached at 50 km/h and 70 km/h.

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1.15 1.05 R² = 0.9197

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Fig. 4. Dependences of vertical accelerations RMS on running speed.

0.82 0.80 0.78 0.76

R² = 0.9127 Speed, km/h

0.74 30

40

50

60

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80

Fig. 5. The dependences of lateral accelerations RMS on running speed.

The dependence of RMS values of vehicle vertical accelerations on travel speed has been concluded according to experimental data. There is polynomial of third degree, whose coefficients are given in Table 1: f ðvÞ ¼ p1 v3 þ p2 v2 þ p3 v þ p4 :

ð3Þ

The high determination coefficient (R2 = 0.9127) confirm the compliance. Table 1. Calculated coefficients of polynomial function (3). Coefficient Value 0.000007 p1 p2 −0.0013 p3 0.0759 p4 −0.3814

The dependence of RMS values of vehicle lateral accelerations on travel speed has been concluded according to experimental data. There is polynomial of fourth degree, whose coefficients are given in Table 2: f ðvÞ ¼ p1 v4 þ p2 v3 þ p3 v2 þ p4 v þ p5 :

ð4Þ

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The high determination coefficient (R2 = 0.9197) confirm the compliance. Dependence of dispersion of vertical maximal acceleration on running speed is given in Fig. 6.

Fig. 6. Dependence of dispersion of vertical maximal accelerations on running speed.

The passenger car body maximal vertical acceleration and passenger car running speed dependence quantiles fields ranges from 2.1 m/s2 to 2.9 m/s2, their averages clearly reproducing acceleration growth at 70 km/h and its decrease to 80 km/h. The range of quantiles plots is more directed towards the positive direction of the graph. This confirms the incidental fixation of the maximum vertical acceleration of the car body, which may have been affected by the resonance. Plots ranges from 5.2 m/s2 to 6 m/s2. This shows a fairly uniform scattering of values at different speeds. Data collected during experiment was evaluated by Sperling smooth running indicator (Fig. 7). As seen from Fig. 7, the Sperling smooth running indicators comply with the requirements for ride quality for passenger cars. The highest value of the indicator in lateral direction has been reached at velocity of 40 km/h. This is influenced by the phenomenon of vehicle “hunting”. Analysis of experimental data gives us values of the shock acceleration ratio (SAR). This is equal to the ratio of the maximum acceleration value and the RMS acceleration value. SAR value does not exceed 4.

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Fig. 7. Dependence of Sperling smooth running indicator on vehicle velocity: (a) vertical vibration; (b) lateral vibration.

These results, obtained during the field tests, are given in Table 3. Table 3. Calculated SAR values Velocity, km/h 30 40 50 60 70 80 SAR (vertical) 5.24 4.75 7.20 6.79 4.52 5.85 SAR (lateral) 4.08 3.73 3.79 3.81 4.17 5.99

SAR values of vertical oscillations are significantly overestimated and exceed the established values by 1.3–1.8 times. This is caused by wheel and track defects, the construction of passenger car and suspension stiffness and damping parameters.

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5 Conclusions 1. After having processed the experiment results, the dependencies of lateral and vertical acceleration change of car body on running speed were concluded. The high determination coefficients (R2 = 0.9127 and R2 = 0.9197) shows that the functions are selected correctly and correlates well with the results of the experiment. 2. The passenger car body maximal vertical acceleration and passenger car running speed dependence quantiles fields ranges from 2.1 m/s2 to 2.9 m/s2, their averages clearly reproducing acceleration growth at 70 km/h and its decrease to 80 km/h. This indicates that vibration resonance was reached at 70 km/h. 3. The SAR values exceed the established values by 1.3–1.8 times. In order to reduce the SAR values, it is necessary to change the suspension parameters taking into account the relevant driving conditions. 4. The executed experimental tests of travelling passenger car with wheel damage enable to expand study opportunities taking into account the impact of larger-scale railway track and vehicle parameters on running dynamic processes. Acknowledgment. This research was funded by a grant (No. S-LU-18-12) from the Research Council of Lithuania. This research project “EFFECT-RAIL” was performed in cooperation with the Volodymyr Dahl East Ukrainian National University, Ukraine.

References 1. Steišūnas, S.: Research on dynamic processes of wagon wheelsets with flat impact on rail. Doctoral dissertation, 141 p. Technika, Vilnius (2017) 2. Steišūnas, S., Dižo, J., Bureika, G., Žuraulis, V.: Examination of vertical dynamics of passenger car with wheel flat considering suspension parameters. Procedia Eng. 187, 235– 241 (2017). Transportation Science and Technology: Proceedings of the 10th International Scientific Conference, TRANSBALTICA 2017, 4–5 May 2017. Vilnius Gediminas Technical University, Vilnius, Lithuania. Elsevier Ltd. Amsterdam, ISSN 1877-7058 3. Гapипoв, Д.C.: Пpoгнoзиpoвaниe paзвития пoлзyнa и oцeнкa eгo влияния нa динaмикy кoлeca: aвтopeфepaт диcepтaции кaндидaтa тexничecкиx нayк. Caмapa: CaмГУПC, 22 p. (2012) 4. Cлaдкoвcкий, A., Пoгopeлoв, Д.Ю.: Иccлeдoвaниeиccлeдoвaниe динaмичecкoгo взaимoдeйcтвия в кoнтaктe кoлeco-peльc пpи нaличии пoлзyнoв нa кoлecнoй пape, Bicник Cxiднoyкpaїнcькoгo нaцioнaльнoгo yнiвepcитeтy 5, 88–95 (2008) 5. Morys, G.B.: Zur Entstehung und Verstarkung von Unrundheiten an Eisenbahnradern bei hohen Geschwindigkeiten. Ph.D. thesis. Universitat Karlsruhe (TH), Germany, 152 p. (1998) 6. Bogdevičius, M., Žygienė, R., Dailydka, S., Bartulis, V., Skrickij, V., Pukalskas, S.: The dynamic behaviour of a wheel flat of a railway vehicle and rail irregularities. Transport 30(2), 217–232 (2015) 7. Bi, J., Gu, Y., Murray, M.H.: A dynamic wheel–rail impact analysis of railway track under wheel flat by finite element analysis. Veh. Syst. Dyn. 51(6), 784–797 (2013)

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8. Кyдюpoв, Л.B., Гapипoв, Д.C.: Maтeмaтичecкaя мoдeль paзвития плocкoгo дeфeктa нa пoвepxнocти кaтaния кoлeca c yчeтoм yпpyгocти пoдвecки и вepтикaльнoй нepoвнocти пyти. Becтник Caмapcкoгo гocyдapcтвeннoгo тexничecкoгo yнивepcитeтa, Cepия: Физикo-мaтeмaтичecкиe нayки 1(20), 178–187 (2010) 9. Maskeliūnaitė, L., et al.: Using AHP method for determining the significance of quality criteria of passenger transportation by train based on service people. Sci. – Future Lithuania 1(6), 57–62 (2009) 10. Graa, M., Nejlaoui, M., Houidi, A., Affi, Z., Romdhane, L.: Modeling and simulation for vertical rail vehicle dynamic vibration with comfort evaluation. Multiphys. Model. Simul. Syst. Des. Monit. Appl. Condition Monit. 2, 47–57 (2015) 11. Bogdevičius, M., Žygienė, R., Bureika, G., Dailydka, S.: An analytical mathematical method for calculation of the dynamic wheel–rail impact force caused by wheel flat. Veh. Syst. Dyn.: Int. J. Veh. Mech. Mobilitym 54(5), 689–705 (2016)

About Physical Aspects of Increasing Durability of Aluminum Alloys Due to ImpactOscillatory Loading Mykola Chausov1, Pavlo Maruschak2(&), Elena Zasimchuk3, Andrii Pypypenko1, Roman Bishchak4, and Iurii Burda5 1

National University of Life and Environmental Sciences of Ukraine, Heroiv Oborony str.15, Kiev 03041, Ukraine [email protected] 2 Ternopil National Ivan Pul’uj Technical University, Rus’ka str. 56, Ternopil 46001, Ukraine [email protected] 3 Institute of Metal Physics of the National Academy of Sciences, Vernadsky str. 36, Kiev 252142, Ukraine 4 Ivano-Frankivsk National Technical University of Oil and Gas, Ivano-Frankivsk, Karpatska str. 15, Ivano-Frankivsk 76019, Ukraine [email protected] 5 Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanical Systems Engineering, Überlandstrasse 129, 8600 Dübendorf, Switzerland [email protected]

Abstract. Two physical mechanisms that contribute to increasing the fatigue life of aluminum alloys after the realization of impact-oscillatory loading are revealed by experiment. Firstly, it is established that the realization of dynamic non-equilibrium processes (DNP) in sheet aluminum alloys leads to the creation of dissipative structures in the volume of alloys, the density of which is less than that of the main material. As a result, the effects of microextrusions caused by less dense dissipative structures are manifested on the surface of alloys. Secondly, it is shown that the phase composition of alloys, which in addition to the solid aluminum-based solution includes the reinforcing phases in the form of dispersed Al2Cu particles (the so-called H-phase) and CuAl2Mg (the so-called S-phase), changes favorably in such a way that the concentration of particles of the S-phase decreases dramatically, and the concentration of particles of the H-phase increases. Keywords: Impact-oscillatory loading Fatigue life


Aluminum alloys
Surface layers


The original version of this chapter was revised: The author's name has been corrected. The correction to this chapter is available at https://doi.org/10.1007/978-3-030-38666-5_67 © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 572–580, 2020. https://doi.org/10.1007/978-3-030-38666-5_60

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1 Introduction Sheet aluminum alloys D16ChATW and 2024-T351 are widely used for the manufacture of aircraft and rocket structures. During operation, they are subjected to complex loads, in particular, cyclic ones [1, 2]. Therefore, the task of increasing the fatigue life of aluminum alloys is very relevant. It is known that the influence of energy fields, such as laser, electromagnetic, ultrasonic, and other fields changes the initial physical and mechanical properties of materials, in particular, their surface layers [3–5]. It is established that due to such impulse influences, dynamic non-equilibrium processes (DNP) arise in materials that lead to significant changes in the initial mechanical properties of structural materials [3, 6, 7], in particular, an increase in their fatigue life. Most of the results obtained are experimental ones that focus on the consideration and optimization of the physical and technological aspects of such processing methods. With the improvement of surface modification techniques, the fatigue life of materials becomes longer, on the one hand, and there arises the need in using complex technological equipment, on the other hand. A separate issue is the necessity to deepen the physical and mechanical justification of the effects that contribute to the improvement of the physical and mechanical properties of materials of surface layers. The development and testing of a new effective method for increasing the fatigue life of aluminum alloys by impulse introduction of power energy into the alloys under impact-oscillatory loading makes it technologically easier and cheaper to achieve a positive effect for the physical and mechanical properties of aluminum alloys and, accordingly, to increase the fatigue life of aluminum alloys as compared to the known analogues. Particularly important is that this process is manageable. Its parameters are regulated by changing the intensity of the impulse introduction of energy into the material at room temperature. In this paper, the physical aspects of the detected mechanical effects are considered based on the results of previous studies conducted by the authors with a focus on increasing the fatigue life of aluminum alloys D16ChATW and 2024-T351 by impactoscillatory deformation.

2 Methods of Mechanical and Physical Research Specimens (Fig. 1) of sheet industrial aluminum alloys D16ChATW and 2024-T351 with a thickness of 3 mm were tested. The strain measurement base was 16 mm. The impact-oscillatory loading was generated by a modified hydraulic setup for static tests ZD-100Pu, its main methodological aspects are described in detail in [8, 9]. The main idea of the proposed method is a high-speed stretching of the material, followed by the imposition of a high frequency (several kilohertz) oscillatory process on it, which corresponds to the own frequency of the test machine. The specimens were loaded with a cyclic stretching at the Instron-8802 setup with a frequency of 15 Hz and the cycle asymmetry coefficient R = 0.1.

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Fig. 1. Test specimen.

In this paper, the optimal effect of the intense impulse introduction of power energy on the maximum increase in the fatigue life of aluminum alloys is not evaluated; this is the subject of separate research. In this research, attention is paid specifically to the positive effect of the impulse introduction of energy on an increase in the fatigue life of aluminum alloys with a fixed value of the impulse introduction of power energy into alloys, under which jumps of plastic deformation of 10-11% were recorded during the DNP [6, 7]. At the same time, special attention is paid to finding physical aspects of increasing the fatigue life of aluminum alloys due to impact-oscillatory loading. Two batches of specimens from each of the studied alloys were subjected to cyclic stretching: one – in the initial state, the other – after the previous impact-oscillatory loading. The chemical composition of aluminum alloys D16ChATW and 2024-T351 is given in Table 1.

Table 1. Chemical composition of aluminum alloys D16ChATW and 2024-T351. 2024-T351, % Si Fe Cu Mn 0.05 0.13 4.7 0.70 D16ChATW, % Si Fe Cu Mn 0.11 0.18 4.4 0.63

Mg Cr Zn Ti 1.5 0.01 0.02 0.04 Mg Cr Zn Ti 1.4 0.01 0.01 0.07

Changes in the physical and mechanical properties of the surface layers after impact-oscillatory loading were estimated by several methods. In particular, to study the relief formation kinetics during the impulse introduction of energy into alloys, a special monocrystalline sensor was firmly fixed on the specimen surface with the PASCO Fix adhesive, and shooting was performed. The speed of shooting the specimen surface during the impact-oscillatory loading was 600 frames per second. In addition, changes in the topography of flat surfaces of specimens in the initial state and after the realization of DNP were evaluated using the 3D Optical Surface Metrology System Leica DCM8 device.

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The relief parameters were compared in the central areas of specimens in the initial state and after the realization of the impact-oscillatory loading. Changes in the phase composition of alloys were evaluated for the concentration of Al2Cu (the so-called H phase) and CuAl2Mg (so-called S-phase) nanoparticles in the initial state and after the realization of DNP by statistical processing of TEM-structures of specimens per unit area of foil [10].

3 Results of Mechanical and Physical Research Figure 2 shows the results of the mechanical tests performed. It was found that the preliminary impulse introduction of power energy into aluminum alloys due to impactoscillatory loading contributes to increasing the durability of alloys with subsequent cyclic loading.

Fig. 2. Fatigue curves of specimens from aluminum alloys in the initial state (1) and after DNP (2): (a) – alloy 2024-T351; (b) – alloy D16ChATW [6].

Figure 3 shows the stress-strain diagram for the D16ChATW alloy, taking into account the additional impulse loading (Fig. 3a), the kinetics of the sensor relief variation during the application of the additional impulse loading (Fig. 3b), and the monocrystal relief upon completion of the dynamic non-equilibrium process (Fig. 3c). The shape of relief was considered one of the parameters which allows us to estimate the condition of the material surface [1, 11], since the formed morphostructures result from the manifestation of new dissipative structures created in the process of the DNP realization. The occurrence of microextrusions and less dense dissipative structures on the specimen surface indicates changes in the structure and mechanical properties not only in the volume of materials, but, above all, in the surface layers. The newly created hybrid surface structure featuring the alternation of soft and solid microzones can aid in arresting the nucleation and propagation of microcracks on the specimen surface during cyclic loading and thus positively affect an increase in the fatigue life of aluminum alloys. The obtained data are mainly qualitative, since they do not allow us to quantify the height of the formed microextrusions. The analysis of the height and distance

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a)

c)

f = 600 frames per second; darea = 0.3 mm b)

Fig. 3. Stress-strain diagram for the D16ChATW alloy taking into account additional impulse loading (Pimp = 82.9 kN) – a; kinetics of the sensor relief variation during the application of additional impulse loading – b; sensor relief after the application of additional impulse loading – c.

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between the formed microextrusions was performed according to the surface topography of specimens in the initial state and after the application of impact-oscillatory loading using the 3D Optical Surface Metrology System Leica DCM8 device. Figure 4 presents the results of the quantitative evaluation of changes in the topography of flat surfaces of specimens from the D16ChATW alloy in the initial state

Fig. 4. Topography of flat surfaces of specimens from D16ChATW alloy in the initial state (a, c) and after DNP (b, d): (a), (b) – 2D-measurement; (c), (d) – 3D-measurements.

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and after the DNP using the 3D Optical Surface Metrology System Leica DCM8 device. Here, Fig. 4a and Fig. 4c correspond to the specimen in the initial state, and Fig. 4b and Fig. 4d correspond to the specimen after the application of impactoscillatory loading. These data qualitatively coincide with the results shown in Fig. 3, however, in contrast to Fig. 3, they allows us to quantify not only the distances between microextrusions, but also the height of the microextrusions on the specimen surface (see Fig. 4c and Fig. 4d). In the future, this feature can be used as a parameter for changing the structure of the surface layers when choosing the optimal mode for the impulse introduction of energy into aluminum alloys in order to maximize the fatigue life of alloys. Here, Fig. 4a and Fig. 4c correspond to the specimen in the initial state, and Fig. 4b and Fig. 4d correspond to the specimen after the application of impactoscillatory loading. These data qualitatively coincide with the results shown in Fig. 3, however, in contrast to Fig. 3, they allows us to quantify not only the distances between microextrusions, but also the height of the microextrusions on the specimen surface (see Fig. 4c and Fig. 4d). In the future, this feature can be used as a parameter for changing the structure of the surface layers when choosing the optimal mode for the impulse introduction of energy into aluminum alloys in order to maximize the fatigue life of alloys. It is known that in the course of plastic deformation, especially in case of a sudden change in the conditions of the mechanical influence on the material, the instability of the previously created structure may occur, followed by the self-organization of the deformed material in the form of a structure that contributes to deformation. As shown by the experimental research conducted by the authors, in heterophasic alloys, to which aluminum alloys belong, this is caused by the formation of synergistic banded structures [9]. During the dynamic non-equilibrium processes, the fluid-like structure inside the bands contributes to the hydrodynamic plastic flow of the material. In addition, the relaxational phase transformation of this non-crystalline structure into crystalline micro-grains after unloading makes it possible to obtain a relatively stable nanostructure [10]. In Table 2, on the example of processing of the TEM-structures of specimens from the 2024-T351 alloy [10], the variation of the phase composition of the alloy is shown. In addition to the aluminum-based solid solution, the alloy includes the reinforcing phases in the form of dispersed Al2Cu (the so-called H-phase) and CuAl2Mg (so-called S-phase) particles during the realization of DNP due to impact-oscillatory loading. Table 2. The concentration of Al2Cu particles (the so-called H-phase) and CuAl2Mg (the socalled S-phase) in the 2024-T351 alloy in the initial state and after the realization of DNP. Concentration of particles in the alloy Initial state After DNP H-phase 0.69 1.59 S-phase 3.13 0.24 Total value 3.82 1.83

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Analysis of the results summarized in Table 2 shows that the previous impulse introduction of energy into the alloy contributes to a significant decrease in the concentration of the S-phase particles and an increase in the concentration of the H-phase particles, however, in such a way that the total concentration of particles is always less as compared with the initial state. Thus, the phase composition of the 2024-T3 alloy changes significantly in the process of the impulse introduction of energy. This is due to the fact that plastic deformation, which is far from the thermodynamic equilibrium, is accompanied by synergetic structure formation in the case of elimination of the dislocation slip. An alternative mechanism of plastic deformation is realized under such conditions, which is connected with the self-organization of the structure in the form of hydrodynamic flow channels with a liquid-like structure inside [9, 10, 12, 13]. A structure of this kind, which is saturated with vacancy defects, contributes to the dissolution of S-phase particles and the separation of H-phase particles. It is proved that such phase composition of the alloy has a greater resistance to the nucleation of fatigue cracks and, therefore, the fatigue life of the alloy becomes longer [10].

4 Conclusions Two physical mechanisms that are manifested in aluminum alloys D16ChATW and 2024-T351 under impact-oscillatory loading are found and analyzed. The creation in aluminum alloys of dissipative thin-banded structures in the process of DNP, the density of which is less than that of the main material, as well as a sudden change in the phase composition of alloys lead to changes in the structure of the surface layers of materials. The structure of the surface layers of the alloys becomes hybrid with the alternation of soft and hard microzones and a significant oversaturation with the Hphase particles. These factors, in the authors’ opinion, lead to a significant increase in the fatigue life of the investigated alloys.

References 1. Shaniavski, A.A.: Safety fatigue fracture of elements of aircraft constructions. Synergetic in engineering applications, Ufa (2003). (in Russian) 2. Ignatovich, S.R., Menou, A., Karuskevich, M.V., Maruschak, P.O.: Fatigue damage and sensor development for aircraft structural health monitoring. Theor. Appl. Fract. Mech. 65, 23–27 (2013) 3. Maruschak, P., Menou, A., Chausov, M., Mocharskyi, V.: Fractographic analysis of surface and failure mechanisms of nanotitanium after laser shock-wave treatment. Key Eng. Mater. 592–593, 346–349 (2013) 4. Markushev, M.V., Avtokratova, E.V., Kazakulov, I.Y., et al.: Microstructure and properties of an aluminum D16 alloy subjected to cryogenic rolling. Russ. Metall. 4, 364–369 (2011) 5. Fridlyander, I.N., Berstenev, V.V., Tkachenko, E.A., et al.: Effect of heat treatment and deformation on the grain size and mechanical properties of duralumin-type alloys. Metal Sci. Heat Treat. 45(7–8), 239–245 (2003)

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6. Hutsaylyuk, V., Snieżek, L., Chausov, M., Torzewski, J., Pylypenko, A., Wachowski, M.: Cyclic deformation of aluminium alloys after the preliminary combined loading. Eng. Fail. Anal. 69, 66–76 (2016) 7. Hutsaylyuk, V., Snieżek, L., Torzewski, J., Chausov, M., Berezin, V., Pylypenko, A.: Influence of preliminary combined loading on low cyclic fatigue deformation of aluminum alloy D16ChATV. Procedia Eng. 114, 18–25 (2015) 8. Chausov, N.G., Voityuk, D.G., Pilipenko, A.P., Kuz’menko, A.M.: Setup for testing materials with plotting complete stress–strain diagrams. Strength Mater. 36(5), 532–537 (2004) 9. Chausov, M.G., Berezin, V.B., Pylypenko, A.P., Hutsaylyuk, V.B.: Strain field evolution on the surface of aluminum sheet alloys exposed to specific impact with oscillation loading. J. Strain Anal. Eng. Des. 50(1), 61–72 (2015) 10. Zasimchuk, E., Turchak, T., Baskova, A., Chausov, N., Hutsaylyuk, V.: Structural transformations in metallic materials during plastic deformation. J. Mater. Eng. Perform. 26 (3), 1293–1299 (2017) 11. Lytvynenko, I.V., Maruschak, P.O., Lupenko, S.A., Popovych, P.V.: Modeling of the ordered surface topography of statically deformed aluminum alloy. Mater. Sci. 52(1), 113– 122 (2016) 12. Zasimchuk, E., Baskova, O., Gatsenko, O., Turchak, T.: Universal mechanism of viscoplastic deformation of metallic materials far from thermodynamics equilibrium. J. Mater. Eng. Perform. 27(8), 4183–4196 (2018) 13. Panin, S.V., Burkov, M.V., Lyubutin, P.S., Altukhov, Y., Shakirov, I.V.: Fatigue damage evaluation of carbon fiber composite using aluminum foil based strain sensors. Eng. Fract. Mech. 129, 45–53 (2014)

Special Aspects of Determining the Dynamic Load of the Tank Container During Its Transportation in an Integrated Train Set by a Railway Ferry Alyona Lovska1(&), Juraj Gerlici2, Oleksij Fomin3, Kateryna Kravchenko2, Yuliia Fomina2, and Tomas Lack2 1

Ukrainian State University of Railway Transport, Feuerbach Square 7, Kharkiv 61050, Ukraine [email protected] 2 University of Zilina, Univerzitná, 8215/1, Zilina 01026, Slovak Republic {juraj.gerlici,kateryna.kravchenko,yuliia.fomina, tomas.lack}@fstroj.uniza.sk 3 State University of Infrastructure and Technology, Kyrylivska Street 9, Kiev 04071, Ukraine [email protected]

Abstract. The work presents the special aspects of modeling of dynamic loading of a tank container during its transportation in an integrated train set by a railway ferry. Determination of dynamic loading was carried out by mathematical modeling as well as computer modeling in the CosmosWorks software. Checking of the adequacy of developed models has been carried out by Fisher’s ratio test. It was found that accelerations of a tank container during its transportation by a railway ferry exceed accelerations of it during operating on main trucks. The research will contribute to improving safety of operation and working efficiency of the intermodal transport. Keywords: Tank container Railway ferry transportation


Modeling
Dynamic loading
Acceleration


1 Introduction Prospects for the development of foreign economic relations between the Eurasian countries necessitate putting into operation of the interoperable transport systems. Railferry and container transport have become the most common transport [1–6]. In recent years, the seamless interaction of these two transport components has been traced, by the example of the transportation of intermodal transport trains from Ukraine to China with the involvement of rail-ferry routes across the waters of the Black and Caspian Seas. To ensure the safe movement of containers as a part of integrated train operation in international traffic, it is important to study their dynamic loading. Special attention should be paid to tank containers, due to the additional loading of their bearing structures with a liquid cargo. It is important to note that this issue has not been given © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 581–590, 2020. https://doi.org/10.1007/978-3-030-38666-5_61

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due consideration so far. In connection with the accelerated development of interoperable shipments in the international traffic, determining the loading of bearing structures of tank containers as a part of intermodal transport trains received priority.

2 The Analysis of Recent Research Features of the strength analysis of the 40-foot shipping container floor in the Abaqus/CAEv 6.1 software is given in a paper [7]. Recommendations for the safe operation of this type of container have been proposed. The design features of a tank container for the transport and storage of liquefied natural gas are considered in a paper [8]. The article presents the thermal analysis of the tank container shell. The optimal storage time of the cargo in the tank container has been determined. The strength calculation of the flat wagon frame during transportation by rail ferry is carried out in a paper [9]. In this case, the case of ship rolling motion is considered. It has been taken into account that the flat wagon design is loaded with a conditional load using the maximum load capacity. The paper does not give attention to the issue of containers dynamic loading. The determination of the strength factors of the bearing structure of a flat car made from round pipes during its transportation by a railway ferry is carried out in a paper [9]. The study of the dynamic loading of the flat wagon has been carried out in the absence of own movements of the supporting structure relative to the deck of the railway ferry. These papers did not pay attention to the study of the strength of the tank container for transportation by the railway ferry. The results of determining the stress state of the tank container are given in a paper [10]. The determination of the deviations of the frame and the tank under operating conditions of the load is carried out in the paper. The influence of the loading level of the shell of a tank wagon with a liquid cargo on its static load has been studied in a paper [11]. The article presents the results of the maximum equivalent stresses and deformations in the shell, taking into account the different levels of its load. The strength analysis of the open wagon improved design during transportation by rail ferry is carried out in a paper [12]. The dislocation fields of maximum equivalent stresses in the body are determined, which allowed for the conclusion that the proposed solutions are feasible. The task of the tank container dynamic loading determining during transportation by railway ferry is not to be set in the article. The analysis of the freight cars modernization technology during their periodic repairs is given in a paper [13]. Within the framework of the project, it is proposed to manufacture the car body from composite panels, and to paint with anti-corrosion materials. The strength analysis of an open wagon body that has exhausted its regulatory resource is carried out in an article [14]. When constructing the strength model, the actual values of dynamic loads acting on the wagon during shunting collision are taken into account.

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It is important to note that these papers do not pay attention to the issue of improving vehicles in order to ensure durability during transportation by railway ferries. The analysis of the dynamic properties of rolling stock under operation relative to the track is carried out in a paper [15]. The modern methods of the vehicles dynamics modeling have been used during the research. The study of resistance to the motion of the vehicles running gear under operational loads is carried out in a paper [16]. Moreover, it was taken into account that the wagon is moving in curves with a constant speed of movement. The authors do not set the problem of determining the stability of vehicles during transportation by a railway ferry.

3 The Purpose of the Article Justification of the features of determining the dynamic loading of the tank container during its transportation in an intermodal train set by a railway ferry. To achieve this goal, the following tasks are defined: 1. To conduct a study of the tank-container dynamic loading during transportation by a railway ferry using mathematical modeling methods. 2. To conduct a study of the tank-container dynamic loading during transportation by a railway ferry by computer simulation methods. 3. To verify the developed models.

4 The Main Content of the Article To determine the tank-container dynamic loading during transportation by sea, a mathematical model was compiled (1). At the same time, the motions of the system “railway ferry - tank container - bulk cargo” have been considered during the heel (Fig. 1). The model takes into account that the flat wagon with the tank container located on it is rigidly fixed relative to the railway ferry deck and does not have its own movements. The description of the moving process of the tank container with bulk cargo was carried out according to the method described in papers [17]. The calculations took into account the technical characteristics of the rail ferry “Shipka Heroes” and the hydrometeorological characteristics of the Black Sea [18, 19]. 8

  D B h B _ > 2 2 > > € ðB q_ ¼ p0
þ Kh

FðtÞ; þ 4z Þ q þ K
h > g > 12
g 2 2 2 > > ! ! < k k k X X X 2 Ihi þ mij
cij
€h2 þ mij
cij
lij
€h3 g
mi
zci þ mij
cij
h2 ¼ Fk ; > > > > j¼1 j¼1 j¼1 > > > :I
€ € ij h3  mij
cij
lij
h2 þ g
mij
lij
h3 ¼ 0;

ð1Þ

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where q1 ¼ h1 ;q2 ¼ h2 ;q3 ¼ h3 – generalized coordinates corresponding to the angular displacement relative to the longitudinal axis, respectively, of the railway ferry, the tank container and the bulk cargo. The coordinate origin is located at the center of mass of the railway ferry; D – weight water displacement; B – width of the rail ferry; h – molded depth of the rail ferry; Kh – coefficient of fluctuations resistance; zg – coordinate of the center of gravity of the railway ferry; p0 – wind force; FðtÞ – law of action of a force, which excites the movement of the railway ferry with wagons placed on its decks; Iij – the moment of inertia of the pendulum; mij – mass of the j-th pendulum in the i-th tank container; cij – the distance from the plane zi ¼ 0 to the point of fixation of the j-th pendulum in the i-th tank container; lij – the length of the j-th pendulum; Ih – the reduced moment of inertia of the i-th tank container and liquid cargo which does not participate in the movement relative to the tank; zci – height of the center of gravity of the tank container; mi – the body weight equivalent to the i-th tank container with the part of the bulk cargo which does not participate in the movement relative to the tank; Fk – the moment of forces arising between the container and the flat wagon. Gasoline is accepted as a liquid bulk cargo. The hydrodynamic characteristics of the bulk cargo are calculated for the case of the maximum permissible shell load [20]. The movement of the bulk cargo was described by a set of mathematical pendulums [17]. The mathematical model is solved in the MathCad software [21, 22]. At the same time, it was reduced to Cauchy normal form. The differential equation system (1) in normal form was solved by integration according to the Runge-Kutta method. On the calculations basis, accelerations acting on a tank container placed on a flat wagon during its transportation by a railway ferry (Fig. 1) have been obtained. The research results allow for the conclusion that the maximum accelerations acting on the tank container are about 3.8 m/s2 (Fig. 2). Taking into account the horizontal component of the acceleration of gravity, due to the angle of inclination of the railway ferry, the total acceleration will be 5.87 m/s2 (0.6 g).

Fig. 1. Scheme of movements of a tank container with a liquid cargo when the railway ferry wallows

Fig. 2. Accelerations acting on the tankcontainer.

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To study the dynamic loading of a tank container during its transportation as a part of an intermodal train by a railway ferry, computer simulation using the finite element method implemented in the CosmosWorks software [23] has been carried out. Spatial isoparametric tetrahedras have been used as finite elements. The number of nodes in the mesh was 396,934; the number of elements was 1,192,935. The maximum element size was 70 mm, the minimum was 14 mm. The maximum aspect ratio was 13,317, the percentage of elements with the aspect ratio less than 3 was 36.7, and the percentage with the aspect ratio more than 10 was 15.4. The model for determining the dynamic loading of a tank container placed on a flat car is given in Fig. 3. The model takes into account that the vertical load from the container tanks PFW placed on a flat wagon, the horizontal load on the fitting supports v PFW from the fittings, as well as the load acting on the flat car through the nodes for h fixing the chain ties Pcht are acting on the flat wagon. In this case, the load that is transmitted to the flat wagon frame through chain ties was decomposed into components, taking into account their spatial distribution. The flat wagon was fastened in the areas of support for the trucks, as well as the working surfaces of mechanical stopjacks. For this purpose, the circular plates having the diameter equal to the diameter of the working parts of mechanical stop-jacks were installed on the main longitudinal girders of the flat car frame in the zone of their interaction with the span bolsters. A vertical-static load Pstv , a pressure from a liquid cargo Plc , a wind load Pw and a dynamic load Pd act on the tank container shell. The tank container was fixed in the areas of its support on the flat wagon. Steel 09G2S was used as a construction material. The calculation results are shown below (Figs. 4 and 5).

Fig. 3. Model for determining the dynamic loading of a tank container placed on a flat car.

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Fig. 4. Distribution of accelerations acting on a tank container placed on a flat wagon (side view).

Fig. 5. Distribution of accelerations acting on a tank container placed on a flat wagon (bottom view).

In this case the maximum accelerations occur in the frame of the tank container from the side of the chain ties tension and are about 0.5 g. In the upper part of the tank container shell accelerations amounted to 0.33 g. In order to verify the developed models, Fisher’s ratio test (2) was applied. The input variable of the mathematical and computer models is the angle of heel, and the output is the acceleration acting on the tank container [24]. Fp ¼

S2ad ; S2y

ð2Þ

where S2ad – adequacy dispersion; S2y – reproducibility dispersion. The adequacy dispersion was calculated according to the formula: n  P

S2ad ¼ i¼1

yi  yci fi

 ;

ð3Þ

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where yci – calculated value of the variable obtained by modeling; fi – number of degrees of freedom. fi ¼ N  q;

ð4Þ

where N – number of trials in the planning matrix; q – number of equation coefficients. The reproducibility dispersion was calculated using the formula: S2y ¼

n 1X S2 ; N i¼1 i

ð5Þ

where S2i – dispersion in each line where parallel experiments were conducted. The dependence of the accelerations acting on the tank container placed on the flat wagon versus the railway ferry roll angle is shown in Fig. 6.

Fig. 6. Dependence of the accelerations acting on the tank container placed on the flat car on the heeling angle of the railway ferry.

The results of determining of the accelerations obtained by modeling of the dynamic loading of the tank container are shown in Table 1. The required number of static data is determined by the formula [25]. n¼

t2
r2 ; d2

ð6Þ

where t – is determined from the formula U ðtÞ ¼ c=2; U ðtÞ – Laplace’s function, tabulated value; r – mean-square deviation of the random variable under consideration, which should be known a priori, even before the experimental measurements; d2 – absolute error of measurement result.

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Table 1. Numerical values of the accelerations acting on the tank container placed on the flat car when the railway ferry oscillates. Angle of heel Value of the acceleration, g Mathematical model Computer model 1.5 1.2 0.6 3.0 1.53 1.06 4.5 1.97 2.08 6.0 2.35 2.75 7.5 3.46 3.1 9.0 3.87 3.72 10.5 4.74 4.05 12.0 5.87 4.68

The calculation results showed that with dispersion of reproducibility is Sy = 2.71 and dispersion of adequacy is S2ad ¼ 3:13, the actual value of the Fisher’s ratio test is Ft = 3.58, which is less than the table value of the criterion Ft = 3.58. So the hypothesis about the adequacy of the developed model is not denied.

5 Conclusions Based on the conducted research, we can make the following conclusions: 1. The dynamic loading of the tank container in a set of an intermodal train during its transportation by a railway ferry has been determined by mathematical simulation. It is found that the maximum accelerations acting on the tank container, taking into account the horizontal component of the gravity acceleration, due to the slope angle of the rail ferry are 5.87 m/s2 (0.6 g); 2. The dynamic loading of the tank container as a part of an intermodal train during its transportation on a railway ferry has been determined by computer simulation. The maximum accelerations in this case occur in the frame of the tank container from the tension side of the chain ties and are 4.68 m/s2 (0.5 g); 3. Verification of the developed models has been conducted. It is found that with reproducibility dispersion Sy = 1.12 and adequacy dispersion S2ad ¼ 3:14, the actual value of Fisher’s ratio test is less than the tabular one. So the hypothesis of adequacy is not denied; 4. The conducted research will contribute to the creation of new generation tank containers with improved technical, economic and ecological indexes, as well as to increase the efficiency of interoperable transportation through international transport corridors.

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References 1. Lack, T., Gerlici, J.: Modified strip method utilization for wheel/rail contact stress evaluation. In: 9th International Conference on Contact Mechanics and Wear of Rail/Wheel Systems, CM 2012, Chengdu, China, pp. 87–89 (2012) 2. Lack, T., Gerlici, J.: Wheel/rail contact stress evaluation by means of the modified strip method. Commun. Sci. Lett. Univ. Žilina 15(3), 126–132 (2013) 3. Baran, P., Brezáni, M., Kukuča, P., Šťastniak, P.: Basic dynamical analysis and comparison of balancing systems of non-conventional piston machine FIK. Procedia Eng. 192, 34–39 (2017) 4. Dižo, J., Harušinec, J., Blatnický, M.: Computation of modal properties of two types of freight wagon bogie frames using the finite element method. Manuf. Technol. 18(2), 208– 214 (2018) 5. Kukuča, P., Barta, D., Dižo, J., Caban, J.: Piston kinematics of a combustion engine with unconventional crank mechanism. In: MATEC Web of Conferences, vol. 244, p. 03006 (2018) 6. Šťastniak, P.: Wagon chassis frame design with adaptable loading platform. Manuf. Technol. 15(5), 935–940 (2015) 7. Rzeczycki, A., Wisnicki, B.: Strength analysis of shipping container floor with gooseneck tunnel under heavy cargo load. Solid State Phenom. 252, 81–90 (2016) 8. Lisowski, E., CzyĪycki, W.: Transport and storage of LNG in container tanks. J. KONES Powertrain Transp. 18(3), 193–201 (2011) 9. Fomin, O., Gerlici, J., Lovsksaya, A., Kravchenko, K., Prokopenko, P., Fomina, A., Hauser, V.: Research of the strength of the bearing structure of the flat wagon body from round pipes during transportation on the railway ferry. In: MATEC Web of Conferences on “Horizons of Railway Transport”, 10th Year of International Scientific Conference, 21 November 2018, vol. 235, pp. 1–5 (2018) 10. Bhattacharyya, R., Hazra, A.: A study on stress analysis of ISO tank container. In: 58th Congress of the Indian Society of Theoretical and Applied Mechanics, pp. 1–5 (2013) 11. Trejo-Escandón, J.O., Leyva-Díaz, A., Tamayo-Meza, P.A., Flores-Herrera, L.A., SandovalPineda, J.M.: Study of the effect of liquid level on the static behavior of a tank wagon. Int. J. Eng. Res. Sci. Technol. 4(1), 18–25 (2015) 12. Fomin, O., Gerlici, J., Lovska, A., Kravchenko, K., Prokopenko, P., Fomina, A., Hauser, V.: Durability determination of the bearing structure of an open freight wagon body made of round pipes during its transportation on the railway ferry. Commun.-Sci. Lett. Univ. Zilina 21(1), 28–34 (2019) 13. Placzek, M., Wrobel, A., Buchacz, A.: A concept of technology for freight wagons modernization. In: 20th Innovative Manufacturing Engineering and Energy Conference. IOP Conference Series: Materials Science and Engineering, vol. 161, pp. 1–12 (2016). https:// doi.org/10.1088/1757-899x/161/1/012107 14. Okorokov, A.M., Fomin, O.V., Lovska, A.O., Vernigora, R.V., Zhuravel, I.L., Fomin, V.V.: Research into a possibility to prolong the time of operation of universal semi-wagon bodies that have exhausted their standard resource. Eastern-Eur. J. Enterp. Technol. 3(93), 20–26 (2018). https://doi.org/10.15587/1729-4061.2018.131309 15. Suarez, B., Felez, J., Maroto, J., Rodriguez, P.: Sensitivity analysis to assess the influence of the inertial properties of railway vehicle bodies on the vehicle’s dynamic behavior. Vehicle Syst. Dyn. 51, 251–279 (2013)

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16. Tkachenko, V., Sapronova, S., Kulbovskiy, I., Fomin, O.: Research of resistance to the motion of vehicles related to the direction by railway. Eastern-Eur. J. Enterp. Technol. 7(89), 65–72 (2017). https://doi.org/10.15587/1729-4061.2017.109791 17. Bogomaz, G.I., Mehov, D.D., Pilipchenko, O.P., Chernomashentseva, Y.G.: Loading of tank-containers located on the railway platform, with shocks in automatic coupling. Collection of scientific papers “Dynamics and motion control of mechanical systems”, Kiev, pp. 87–95 (1992). (in Russian) 18. Lugovskiy, V.V.: Dynamics of the sea: “Questions related to the teachings of the seaworthiness of the ship”, (Textbook for high schools specialty Hydroaerodynamics), Shipbuilding, p. 199 (1976). (in Russian) 19. Lovska, A.O.: Computer simulation of wagon body bearing structure dynamics during transportation by train ferry. Eastern-Eur. J. Enterp. Technol. 3(75), 9–14 (2015). https://doi. org/10.15587/1729-4061.2015.43749 20. Rules for the Transport of Dangerous Goods. To the agreement on international rail freight. Issue 3/Organization for Cooperation between Railways, p. 531 (2011). (in Russian) 21. Kondratiev, A.V., Gaidachuk, V.E., Kharchenko, M.E.: Relationships between the ultimate strengths of polymer composites in static bending, compression, and tension. Mech. Compos. Mater. 52(2), 259–266 (2019) 22. Kiryanov, D.V.: Mathcad 13. – Sankt-Peterburg, BHV-Peterburg, p. 608 (2006) 23. Alyamovskiy, A.A.: SolidWorks/COSMOSWorks 2006–2007, Engineering Finite Element Analysis. M., p. 784 (2007). (in Russian) 24. Chernova, N.I.: Mathematical statistics, Novosibirsk State University. Novosibirsk, p. 148 (2007). (in Russian) 25. Kosmin, V.V.: Basics of research: Textbook: «Educational and Methodical Center for Education in Railway Transport». Moskow, p. 271 (2007). (in Russian)

Analysis of the Combustion Process of a Compression Ignition Engine Running on Diesel and Natural Gas Saulius Stravinskas(&), Alfredas Rimkus, and Donatas Kriaučiūnas Vilnius Gediminas Technical University, J. Basanavičiaus str. 28, 03224 Vilnius, Lithuania {saulius.stravinskas,alfredas.rimkus, donatas.kriauciunas}@vgtu.lt

Abstract. Compression ignition (CI) engines, although significantly contribute to environmental pollution, are still widely used in transport sector. In order to reduce usage of fossil fuels and environmental pollution, but at the same time run CI engines in transport, use of alternative energy sources must be increased. One way to achieve this goal is to use natural gas (NG) in CI engines. Natural gas is relatively inexpensive also extracted in many parts of the world and can be used as the main fuel in CI engines. This article examines natural gas and diesel blends combustion characteristic after experimental research and numerical modelling in AVL BOOST software. The influence of natural gas concentration on combustion parameters was determined by changing the gas mass fraction in fuel mixture from 0% to 80%. Keywords: Compression ignition engines
Diesel
Natural gas
Combustion parameters

1 Introduction Compression ignition engines are widely used in the world for high reliability, efficiency, adaptability and low cost [1]. However, this type of engine significantly contributes to environmental pollution [2, 3]. The main harmful compounds in the CI engine exhaust gas are particulate matter (PM) and nitrogen oxides (NOx). NOx is the main cause of photochemical smog and acid rain. Particulate matter consists of chemical elements such as black carbon, organic carbon, etc. [4] PM are especially harmful to human health and the environment. Many studies have shown that these particles cause respiratory tract, cardiac and neurological diseases. Furthermore, the World Health Organization has declared the main harmful elements of CI engines exhaust gases as carcinogens [5]. On the other hand, energy demand is increasing, but oil stocks are limited. In order to solve this problem and to reduce environmental pollution, the use of alternative energy sources is inevitable [6]. Among the various alternative fuels, natural gas is viable option for the transport sector. First of all, NG is produced in many parts of the world at an affordable price. Secondly, although the main component of natural gas is methane (CH4), it is still © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 591–600, 2020. https://doi.org/10.1007/978-3-030-38666-5_62

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considered to be an environmental friendly fuel. NG can contribute to reducing greenhouse gas, carbon dioxide (CO2) emissions, as they have lowest carbon/hydrogen (C/H) ratio of all fossil fuels. NG can also significantly reduce NOx and PM concentration in the exhaust gas [7, 8], what is very difficult to implement with regular diesel. Due to NG benefits, it would be rational to use it in CI engines as main or complementary fuels. The main component of NG is methane – the simplest (primary) hydrocarbon. Natural gas combustion is relatively clean and has lower CO2 concentration in exhaust gas than other diesel fuels. As fuel for vehicles, NG has been in use since 1930 [9]. Natural gas is a mixture of different gases. It contains light alkanes such as methane, ethane, propane, n-butane, isobutane and pentane. Also, natural gas contains carbon dioxide, nitrogen and traces of water vapour. The composition of natural gas variates just a little because of the production process and location of extraction. The typical composition of natural gas is given in Table 1 [10]. The use of NG in spark ignition engines is widely developed and adapted, while the use of these gases in CI engines is still under development. Natural gas in CI engine is difficult to ignite due to high gas self-ignition temperature and low cetane number compared to diesel [11, 12]. Physicochemical properties of natural gas and diesel are given in Table 2 [13]. Table 1. Typical component and content of NG [10]. Component Methane Ethane Propane Isobutane n-Butane Isopentane n-Pentane Hexane Nitrogen Carbon dioxide Oxygen Hydrogen

Typical analysis, % Range, % 94.9 87.0–96.0 2.5 1.8–5.1 0.2 0.1–1.5 0.03 0.01–0.03 0.03 0.01–0.03 0.01 Trace to 0.14 0.01 Trace to 0.14 0.01 Trace to 0.06 1.6 1.3–5.6 0.7 0.1–1.0 0.02 0.01–0.1 Trace Trace to 0.02

Table 2. Physicochemical properties of NG and diesel [13]. Properties

Fuel NG Low heating value, MJ/kg 48.6 Heating value of stoichiometric mixture, MJ/kg 2.67 Cetane number – Octane number 130 Auto-ignition temperature, °C 650 Stoichiometric air-fuel ratio, kg/kg 17.2 Carbon content, weight % 75

Diesel 42.5 2.79 52.1 – 180–220 14.3 87

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Fuel burning in the cylinder is one of the most important processes affecting formation of harmful compounds in the exhaust gas, as well as determining efficiency and reliability of the engine [14]. NG and diesel are fuels with different physical and chemical properties. Diesel combustion in the cylinder is performed by mixing fuel with air – diffusional combustion, while NG combust by spreading flame front, as gas is already premixed with air. Adding natural gas into the cylinder affects the combustion process due to changes in the formation of air/fuel mixture and different fuel combustion properties. Analysing the scientific literature, it is clear that the combustion process of a mixture of diesel and natural gas is different compared to the combustion of pure diesel [15]. In the second combustion stage of the diesel and gas mixture, a small amount of diesel starts to burn later (lengthens ignition delay phase) and ignites natural gas. Due to low amount of diesel and low natural gas/air concentration, rate of heat release is lower than for normal (pure diesel) combustion. In third diesel and natural gas combustion stage due to the lower combustion speed and increase in ignition delay the maximum rate of heat release decreases, thus extending the burning time [15]. Therefore, more fuel is burned at the fourth stage of combustion, which can lead to higher exhaust gas temperatures. However, the combustion of diesel and natural gas can be activated by increasing the concentration of NG in the mixture, advanced moment of diesel injection and etc. [16]. The analyzed literature does not contain detailed information on the combustion process changes in the natural gas/diesel dual fuel mode when the NG concentration in the mixture is changed. The aim of the study is to investigate, by using numerical analysis, the change in combustion time and intensity in a compression ignition engine by changing the concentration of NG in the fuel mixture.

2 Research Methodology Experimental studies were carried out using a direct injection compression ignition (CI) engine 1.9 TDI (Table 3) with electronically controlled BOSCH VP37 distribution type fuel pump. This type of engine uses single-phase injection and has two-spring nozzle holders. The two-spring nozzle holder has two compression springs positioned one behind the other. This allows to inject only a small amount of fuel, and as the pressure inside the nozzle holder continues to increase, the main injected fuel quantity is injected continuously [17]. Effective engine torque MB (Nm) and crankshaft revolutions n (rpm.) measured by load stand КI-5543. MB measurement error ±1.23 Nm. Tests performed at constant engine speed n = 2,000 rpm and engine load MB = 45 Nm, exhaust gas recirculation (EGR) – cut off. Start of injection set constant – 6° BTDC. The in-cylinder pressure is measured by a piezoelectric sensor integrated in the glow plug AVL GH13P and obtained with AVL DiTEST DPM 800 equipment. Accuracy of pressure measurement – 1%. The pressure in the engine intake manifold was measured with a pressure gauge DELTA OHM HD 2304.0, measurement error ±0.0002 MPa.

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These fuels are used for testing: pure diesel (D100NG00); 60% diesel and 40% natural gas (D60NG40), 40% diesel and 60% natural gas (D40NG60), 20% diesel and 80% natural gas (D20NG80). The ratio of diesel to natural gas is expressed by mass. Physical and chemical properties of pure fuel (diesel and natural gas) are given in Table 2. Table 3. Parameters of tested engine VW 1.9 TDI (1Z type). Parameter Displacement Compression ratio Power Torque Bore Stroke

Units cm3 – kW Nm mm mm

Value 1,896 19.5 66 (4,000 rpm) 180 (2,000–2,500 rpm) 79.5 95.5

Combustion process analysis of compression ignition engine has been performed with AVL BOOST software subroutine BURN. Numerical modelling, using experimental data (in-cylinder pressure, fuel and air consumption, fuel properties, etc.), determines Fuel Rate of Heat Release FROHR and other combustion parameters. The calculation algorithm is based on the first law of thermodynamics [18]: P w d ðmc
uÞ dmBB dV F þ dQ  dQ da da  hBB
da daP ¼ pc
da P dme dmev dmi þ da
hi  da
h  qev
f
dt ;

ð1Þ

where dðmdac
uÞ – change of the internal energy in the cylinder; pc
dV da – piston work; P dQw dmBB – fuel heat input; da – wall heat losses; hBB
da – enthalpy flow due to blow-by. Heat release is calculated only in the high pressure phase when intake and exhaust valves are closed.

dQF da

3 Research Results and Their Analysis Experimental research and AVL BOOST modeling shows that increased NG concentration from 0% to 80%, delays the start of combustion (SOC) and it starts 1.25° CA later (Fig. 1). Also, the combustion duration (CD) prolongs for 18.4% from 50.7° to 62.1° (Fig. 2).

SOC, °CA

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-4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0 0

20

40 NG, %

60

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Fig. 1. Start of Combustion dependence from NG concentration.

70 60 CD, °CA

50 40 30 20 10 0 0

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Fig. 2. Combustion Duration dependence from NG concentration.

Delay of Start of combustion can be explained by the fact that increasing fraction of NG takes oxygen place in combustion chamber. Also combustion duration increases as natural gas combusts by spreading flame front, because combustion mixture is to lean for spontaneous gas combustion. Vibe shape parameter m shows the dynamics of heat release in the cylinder, which increasing the NG concentration from 0% to 80%, increased by *25% from 0.68 to 0.92 (Fig. 3). This indicates that higher natural gas concentration leads to greater heat release in the later combustion phase. Similar combustion trends of dual fuel mixture have been received by other researchers [16].

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Vibe shape parameter m

1 0.8 0.6 0.4 0.2 0

0

20

40 NG, %

60

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Fig. 3. Shape parameter m dependence from NG concentration.

Late NG combustion is also confirmed by the fuel rate of heat release (Fig. 4). It shows that heat release of pure diesel starts earlier and is more intense comparing to diesel and natural gas mixture.

40

n = 2000 rpm; MB = 45 Nm; SOI = 6 deg. BTDC

35 FROHR, J/°CA

30 25 20 15 10 5 0 -5

-5

0

5

10

15

20

25

30

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Θ, ° CA Fig. 4. Fuel Rate of Heat Release.

For all fuel mixtures maximum combustion temperature variates just a little. However, the maximum combustion temperature of pure diesel measured about 10° earlier than with D20NG80 (Fig. 5). When engine works with diesel in-cylinder temperature rises more intensively up to 7° ATDC than with diesel and NG, but after the peak value in-cylinder temperature starts to drop more intensive (Fig. 6). On the other hand, then adding natural gas to the fuel mixture in-cylinder temperature drops with lower intensity, because of later intensive heat release phase.

T, ºC

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1200 1100 1000 900 800 700 600 n = 2000 rpm; MB = 45 Nm; SOI = 6 deg. BTDC 500 400 300 200 100 0 -15 0 15 30 45 60 Θ, ° CA

75

597

90

Fig. 5. Temperature in-cylinder.

80

n = 2000 rpm; MB = 45 Nm; SOI = 6 deg. BTDC

Temperature rise, ºC / °CA

70 60 50 40 30 20 10 0 -10 -20 -15

0

15 Θ, ° CA

30

45

Fig. 6. Temperature Rise in-cylinder.

During experimental studies in-cylinder pressure was measured directly from cylinder with a piezoelectric sensor integrated in the glow plug and peak pressure difference between directly measured and simulated was no more than 5%. It was measured that using pure diesel the maximum pressure in-cylinder is about 20 bars higher compared to the pressure at D20NG80 (Fig. 7). Also, up to 6° ATDC pressure rise is greater when using diesel, but then, falls faster than with D20NG80 (Fig. 8).

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P, bar

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85 80 n = 2000 rpm; MB = 45 Nm; SOI = 6 deg. BTDC 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 -5 -25 -20 -15 -10 -5 0 5 10 15 Θ, ° CA

20

25

30

Fig. 7. Pressure in-cylinder.

4 n = 2000 rpm; MB = 45 Nm; SOI = 6 deg. BTDC

Pressure rise, bar/° CA

3 2 1 0 -1 -2 -3 -5

0

5

10

15 20 Θ, ° CA

25

30

35

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Fig. 8. Pressure Rise in-cylinder.

Increased heat release with dual fuel (diesel and NG) mode influences engine energetic and ecological parameters. In order to maximize the performance of the duel fuel engine, it is necessary to adjust the rate of heat release by changing the start of fuel injection timing.

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4 Conclusions The following conclusions can be drawn from the experimental studies and AVL BOOST combustion modelling of compression ignition engine working with pure diesel and diesel/natural gas mixture: 1. Increased NG concentration from 0% to 80% delays the start of combustion and it starts 1.25° CA later. Also, the combustion duration prolongs from 50.7° to 62.1° Vibe shape parameter m increased from 0.68 to 0.92. These changes can be explained by the fact that increasing fraction of NG takes oxygen place in combustion chamber and determinates low ignition speed of diesel. Later maximum combustion intensity and increased combustion duration of entire mixtures with natural gas is due to the fact that the NG intensive combustion phase takes place at the end of intensive combustion of diesel. 2. While increasing NG concentration from 0% to 80% pike of FROHR is captured later, for diesel at 1° ATDC, but with 80% of NG at 12° ATDC. Later heat release can be explained both by the reduced amount of injected diesel which acts as the initiator of the combustion as well as by lean air/fuel ratio which exceeds limits for flame front to spread. The large part of natural gas burns in the late phase of combustion due to high temperature and pressure in the cylinder. This is also confirmed by other researchers [15]. 3. Measured that using pure diesel the maximum pressure in-cylinder is about 20 bars higher compared to the pressure at D20NG80. The lower pressure can be explained by the fact that NG combust by spreading flame front, which results in prolonged combustion and lower in-cylinder pressure. The results also correlate with other studies [16]. 4. Diesel-NG mixtures combustion parameters are changing as natural gas concentration increases, so start of diesel fuel injection timing needs to be optimized. Acknowledgment. The results of the research, were obtained by using a virtual internal combustion engine simulation tool AVL BOOST, acquired by signing the Cooperation Agreement between AVL Advanced Simulation Technologies and Faculty of Transport Engineering of Vilnius Gediminas Technical University.

References 1. Wei, L., Geng, P.: A review on natural gas/diesel dual fuel combustion, emissions and performance. Fuel Process. Technol. 142, 264–278 (2016) 2. Torregrosa, A.J., Broatch, A., Garcia, A., Monico, L.F.: Sensitivity of combustion noise and NOx and soot emissions to pilot injection in PCCI diesel engines. Appl. Energy 104, 149– 157 (2013) 3. Tutak, W., Lukács, K., Szwaja, S., Bereczky, Á.: Alcohol–diesel fuel combustion in the compression ignition engine. Fuel 154, 196–206 (2015)

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4. Cheung, K., Ntziachristos, L., Tzamkiozis, T., Schauer, J., Samaras, Z., Moore, K.: Emissions of particulate trace elements, metals and organic species from gasoline, diesel, and biodiesel passenger vehicles and their relation to oxidative potential. Aerosol Sci. Technol. 44(7), 500–513 (2010) 5. Geng, P., Yao, C.D., Wei, L.J., Liu, J.H., Wang, Q.G., Pan, W., et al.: Reduction of PM emissions from a heavy-duty diesel engine with diesel/methanol dual fuel. Fuel 123, 1–11 (2014) 6. Wei, L.J., Yao, C.D., Wang, Q.G., Pan, W., Han, G.P.: Combustion and emission characteristics of a turbocharged diesel engine using high premixed ratio of methanol and diesel fuel. Fuel 140, 156–163 (2015) 7. Abdelaal, M.M., Hegab, A.H.: Combustion and emission characteristics of a natural gasfueled diesel engine with EGR. Energy Convers. Manag. 64, 301–312 (2012) 8. Srinivasan, K.K., Krishnan, S.R., Qi, Y.: Cyclic combustion variations in dual fuel partially premixed pilot-ignited natural gas engines. J. Energy Resour. Technol. Trans. ASME 136(1), 012003 (2014). https://doi.org/10.1115/1.4024855 9. Imran, S., Emberson, D.R., Diez, A., Wen, D.S., Crookes, R.J., Korakianitis, T.: Natural gas fueled compression ignition engine performance and emissions maps with diesel and RME pilot fuels. Appl. Energy 124, 354–365 (2014) 10. Demirbas, A.: Methane gas Hydrate. Springer Science & Business Media (2010) 11. Chandra, R., Vijay, V.K., Subbarao, P.M.V., Khura, T.K.: Performance evaluation of a constant speed IC engine on CNG, methane enriched biogas and biogas. Appl. Energy 88 (11), 3969–3977 (2011) 12. Korakianitis, T., Namasivayam, A.M., Crookes, R.J.: Natural-gas fueled spark-ignition (SI) and compression-ignition (CI) engine performance and emissions. Prog. Energy Combust. Sci. 37(1), 89–112 (2011) 13. Yang, B., Xi, C.X., Wei, X., Zeng, K., Lai, M.C.: Parametric investigation of natural gas port injection and diesel pilot injection on the combustion and emissions of a turbocharged common rail dual-fuel engine at low load. Appl. Energy 143, 130–137 (2015) 14. Tesfa, B., Mishra, R., Zhang, C., Gu, F., Ball, A.D.: Combustion and performance characteristics of CI (compression ignition) engine running with biodiesel. Energy 51, 101– 115 (2013) 15. Papagiannakis, R.G., Hountalas, D.T.: Experimental investigation concerning the effect of natural gas percentage on performance and emissions of a DI dual fuel diesel engine. Appl. Therm. Eng. 23(3), 353–365 (2003) 16. Lounici, M.S., Loubar, K., Tarabet, L., Balistrou, M., Niculescu, D.-C., Tazerout, M.: Towards improvement of natural gas–diesel dual fuel mode: an experimental investigation on performance and exhaust emissions. Energy 64, 200–211 (2014) 17. Reif, K.: Diesel Engine Management. Systems and Components. Springer Vieweg (2014) 18. AVL BOOST VERSION 2011. Theory, Edition (2011)

Anti-wear Properties of Jet Fuel with Camelina Oils Bio-Additives Anna Yakovlieva1(&), Igor Trofimov1, Sergii Boichenko2, Hubert Kuszewski2, and Kazimierz Lejda2 1

National Aviation University, Kosmonavt Komarova ave. 1, Kiev 03058, Ukraine [email protected], [email protected] 2 Rzeszow University of Technology, Powstancow Warszawy ave. 8, 35-959 Rzeszow, Poland [email protected], {hkuszews,klejda}@prz.edu.pl

Abstract. Anti-wear properties of conventional jet fuel, fatty acids ethyl esters bio-additives derived from camelina oil and their blends were investigated experimentally. Anti-wear properties were estimated on a four-ball tester by the value of the scuffing load, friction torque, friction coefficient and the scuffing load applied to the friction pair operating in a tested fuel sample. The state of friction pairs’ surfaces was studied using the system for tribological characteristics of fuels and lubricants investigation by comparing microphotographs of friction pairs’ surfaces. It was determined that lubricity of bio-additives is intensively higher comparing to conventional jet fuel. Bio-additives derived from camelina oil provide formation of better oxidative film on friction pairs’ surface with higher elasticity. It is stipulated by the chemical composition of fatty acids ethyl esters: high polarity of molecules stipulate its’ good adsorption at the surface of friction pair. Adding bio-additives into jet fuel provides strengthening of boundary film and thus improves anti-wear properties of fuel blends. Keywords: Jet fuel
Alternative fuel
Bio-additive
Fatty acids ethyl esters
Camelina oil
Wearing
Lubricity
Scuffing load
Friction surface

1 Introduction Studies described within this paper relate to transport, aviation and machinery constructing industries. In a result of stream rising of prices for natural resources, improvement and studying of exploitation properties of fuels and lubricants became a relevant research-technical problem. That’s why the question of studying and improving anti-wear properties of modern fuels for road and air transport is one of the key questions during considering the priority directions in provision of reliability and durability of mechanisms and tribotechnical systems operation.

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 601–609, 2020. https://doi.org/10.1007/978-3-030-38666-5_63

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2 Literature Overview Modern air transport is equipped with complex hydraulic systems, which perform important functions concerning operation of air and ground vehicles. Reliability of fuels and hydraulic constructions mainly depend on operability of precision friction pairs. In a result of strong wearing, destruction and jamming of friction pairs the breakdown of hydraulic systems can take place. Thus, it will require replacement of worn details. The most common defects include jamming of plunger pumps, laminose, spool and sleeve pairs, destruction of roll bearings, wear of plunger axial bearings etc. Peculiarity of these friction pairs requires critical approach in the question of application of lubricating mediums, mechanical properties of materials, roughness of contacting surfaces, speed of its relative movement. From the previous studies it is known that modern world tends to introducing alternative energy sources in all spheres of industry and air transport in particular [1, 2]. Taking into account wide variety of new alternative fuels and feedstock for its production, much studies have to be done in order to discover operational properties of new fuels. One of the issues to be studied is influence alternative aviation fuels on reliability and durability of aircraft equipment, which is strongly determined by lubricating properties of fuels. From the studies [1–5] it is known that alternative fuels produced from plant oil esters possess high lubrication properties. However, most of the studies are devoted to researches of plant oil esters during application in diesel engines (biodiesel fuel) [4–6]. Taking into account the existing data about lubricating properties of plant oil esters it is necessary to study its impact on anti-wear properties of jet fuels. Durability and reliability of aircraft equipment, mainly fuel system friction pairs strongly depends on anti-wear properties of jet fuels [2, 7–9]. These pairs work in a regimes of rolling friction, sliding friction and combined friction at different loads, temperatures, pressure, speed of relative movement in conditions of liquid or boundary friction. It is known that fuel lubricating properties are determined by complex of physical and chemical parameters [2, 7, 10]. In case of semi-liquid friction the antiwear properties of jet fuels are determined by fuel viscosity and presence of surfactants in fuel that form high strength absorption layer at the wearing surface [2, 9, 10].

3 Aim and Scope of the Study The aim of this article is to study the anti-wear properties of blended jet fuels containing bio-additives based on camelina oil. Thus one of the tasks of the study was comparison of anti-wear properties of blended jet fuels and conventional jet fuels. Analysis of literature sources [1–4, 7, 8, 11, 12] have shown the interest of authors in experimental and theoretical researches related to improving of anti-wear properties of precision friction pairs and studying influence of various components of fuels and oils on anti-wear. One of the ways for prolongation of exploitation period and renewal of tribocouplings is a tribomodification of friction surfaces due to the formation of stable oxidative films. This may be achieved by applying of modified or energetically changed fuels and lubricating materials.

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Lubricity of jet fuel, camelina oil bio-additive and its blends with jet fuel was investigated during the experiment. Conventional oil-derived jet fuel of grade Jet A-1 that meets the requirements of ASTM D1655 [13] was used for testing. Fatty acids ethyl esters (FAEE) of camelina oil were used as bio-additive. Bio-additive was added to fuel blends in quantity: 10%, 20%, 30%, 40% and 50% (vol.). Usually anti-wear properties of jet fuels are determined according to the value of wear of certain friction pair. Wear in the medium of certain fuel of one friction pair can’t characterize lubricating properties of this fuel completely. The change of details material, testing regimes and other factors may significantly influence on wearing of friction pairs. Because of that estimation of anti-wear properties have to be fulfilled in a strictly regulated conditions [7, 10, 14, 15]. Considering the practice worldwide, anti-wear properties of jet fuels are estimated according to the ASTM D5001. Ball-on-Cylinder Lubricity Evaluator – BOCLE. This device imitates oxydation-corrosive type of wearing. Anti-wear properties are estimated quantitatively by the value of wear scar diameter. At the same time another device SLBOCLE was developed and proposed. It is intended for estimating and forecasting anti-scuffing properties of fuels by determining scuffing load. During the last 40 years number of other mechanical stands was developed for determining lubricating properties of jet fuels. However, most of them are not able to imitate the most important type of wearing, which takes place in fuels systems of aircrafts [3, 8]. Anti-wear properties of fuel samples were investigated using a T-02U four-ball tester that consists of the testing device presented at Fig. 1 and a metering-control system. The friction pair installed in testing device is given at Fig. 2 [2, 14].

Fig. 1. Four ball tester T-02U: 1 – body; 2 – power train; 3 – friction pair load bearing drive; 4 – ball cup assembly; 5 – base.

The composition of the friction pair, its assembling and characteristics as well as principle of four-ball tester operation are described in details in previous studies of authors [2, 14].

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Fig. 2. Four ball tester friction pair: 1 – top ball; 2 – bottom balls; 3 – spring clamp; 4 – balls cup.

The studies were fulfilled under the following conditions of the four-ball tester: – rotation speed during tests – 500 rpm, – load increase rate of 409 N/s, – initial temperature of the fuel sample at the start of the test run – 20 ± 1.0 °C.

Friction torque, МТ, Load, Р

According to the methodology of this test a friction pair scuffing occurs when boundary friction torque MT, of 10 Nm is exceeded. This value is determined by the durability of the top ball shank in the friction pair. The friction torque MT and the linearly increasing friction pair load P were recorded during testing [2, 14]. The following Fig. 3 depicts the principle of the method of determining scuffing load applied to the friction pair [2, 14]. Load P, at point 1, where the friction torque value quickly increases is denoted as scuffing load PS. Point 2 is a point of scuffing. At this moment the boundary friction torque MT equal to 10 Nm is reached. The load at point 2 is called seizure load.

Р b.l

МТ

Р

РS

Test run time, s

Fig. 3. The method for determining the scuffing load PS: 1 – the point of scuffing initialization; 2 – point of scuffing.

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Thus, it can be concluded that the fuel with the highest value of applied scuffing load possesses the highest anti-wear properties. It can be said that the boundary film of this fuel has demonstrated the highest durability to damage [2]. Also, the state of friction surfaces was additionally studied using the system for tribological characteristics of fuels and lubricants investigation that was developed by authors [16]. Technical conditions of the system provide possibility to make photographs and video recording of surface transformations in dynamic regime. The friction joint is a transparent glass plate made of photographic glass that passes light without refraction. Microscope objective is mounted in front of the sample, whose surface contacts with glass. The light is focused through the system of lenses into the camera of “PC Camera” type with standard software for processing and fixation of photographs at the monitor and possibility to record the obtained data about friction surfaces. The described system allows fulfilling studies in the sphere of determining the mechanism of oxidation films formation at the surface of metals independantly on the impact of contacting material. The studies were fulfilled according to the friction scheme “finger-surface”; material of samples GCr15 steel – photographic glass, # = 0.30; 0.630 m/s, P = 5 N. Dimensions of the finger-sample are: diameter – 4 mm, length – 25 mm.

4 Results and Discussion The following Figs. 4 and 5 present the friction torque, friction pair load and friction coefficient that were checked during tests. The scuffing load that describes the criteria for anti-wear properties estimation is marked.

Fig. 4. Dependence of friction pair loading force P, friction torque MT and friction coefficient l on testing run time t for jet fuel of grade Jet A1 fuel: PS – scuffing load.

We can see from the graph at Fig. 5a that testing of jet fuel blended with 10% of FAEE bio-additive results in friction coefficient l varying from 0.3 to 0.5 and friction torque MT varying from 0.5 to 3 Nm. From the graph at Fig. 5b we can see that testing of jet fuel blended with 20% of FAEE bio-additive results in friction coefficient l varying from 0.1 to 0.3 and friction torque MT varying from 0.5 to 3 Nm.

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Fig. 5. Dependence of friction pair loading force P, friction torque MT and friction coefficient l on testing run time t for samples of jet fuel blended with camelina oil bio-additives: (a) Jet A-1 +10% FAEE; (b) Jet A-1+20% FAEE; (c) Jet A-1+30% FAEE; (d) Jet A-1+40% FAEE; (e) Jet A-1+50% FAEE; (f) FAEE; PS – scuffing load.

Analogously, comparing the graph at Fig. 5e, describing test of jet fuel blended with 50% of FAEE bio-additive, we observe values of friction coefficient l within a range of 0.15 to 0.4 and values of friction torque MT within a range of 0 to 3 Nm. Thus from the graphs on Fig. 5 we can conclude that anti-wear properties of jet fuels blended with FAEE bio-additives are better comparing to anti-wear properties of conventional jet fuel of grade Jet A-1. Values of scuffing load PS for each tested fuel sample were taken as a key parameter to evaluate anti-wear properties. They are depicted ad compared at Fig. 6. The results given at Fig. 6 allow us concluding that conventional jet fuel of grade Jet A-1 presented the lowest value of scuffing load – 511 N. At the same the highest value of scuffing load was found for camelina oil bio-additive – 2,644 N. Considering conventional jet fuel as a base-line we can assume that use of camelina oil esters positively influences the anti-wear properties of jet fuels. In general obtained results indicate that increasing portion of bio-additive in jet fuel improves its anti-wear properties.

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Fig. 6. Friction pair scuffing load P for each of the tested fuel samples.

As it was mentioned previously, fuel’s surfactants provide ability of fuel or its components to absorb at the surface of metal, create the boundary film and thus protect dry friction of details [2]. Hydrocarbons in conventional jet fuels are non-polar and can not prevent wear of friction pairs [5, 10]. On the contrary, molecules of bio-additives are fatty acids esters and act as natural surfactants [5, 17]. Presence of oxygen atom in carboxyl group in molecules stipulates strong polarity of esters. Such structure provides ability to absorb on surfaces of solid bodies and thus, ability to form polymolecular film – boundary layer. Such view on lubricating properties of fatty acids esters allows us explaining obtained experimental results: regular improvement of anti-wear properties of jet fuel with increasing content of bio-additives. During blending jet fuel with bio-additives the total content of surfactants in fuels rises. In a result the boundary film between friction pair become stronger. Taking into account the abovementioned we may conclude that addition of bioadditive into composition of blended jet fuels provides increasing of surfactants quantity and finally strengthening of boundary film between friction pair [2]. Figure 7 depicts microphotographs of friction pairs’ surfaces, which were obtained after operation in medium of conventional jet fuel, camelina oil bio-additive and jet fuel blend with 20% of bio-additive. Microphotographs were done at the device for studying anti-wear properties of fuels and lubricants according to the method described in work [16]. The sliding distance for all the fuel samples was 8 km. Comparing friction surfaces we can observe that friction surfaces of samples operated in camelina oil bio-additives (Fig. 7b, 7c) are more uniform than friction surfaces of samples operated in conventional Jet A-1 fuel (Fig. 7a). Oxidative films are thinner and more elastic. These results give explanation to smaller values of friction coefficient and values of wearing in equal conditions of sliding distance. Moreover, boundaries of oxidative films on samples are clearly seen at the Fig. 7b. During the

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Fig. 7. Microphotographs of friction pairs’ surfaces (200 times magnification): operation in a medium of (a) Jet A-1; (b) FAEE; (c) Jet A-1+20% FAEE.

process of operation, samples’ films (operation in camelina oil bio-additive medium) become longer and wider comparing to films of sample operated in conventional jet fuel medium. More contrast coloring speaks that sample’s friction surface at Fig. 7b has smaller thickness and it is more elastic.

5 Conclusions A four-ball tester and system for studying tribological characteristics of fuels and lubricants were used for estimating lubricating and anti-wear properties of conventional jet fuel and its blends with bio-additives based on camelina oil FAEE. The research of fuel samples has shown that camelina oil FAEE have better tendency for permanent boundary film creation comparing to conventional jet fuel within. The reason for this effect is surface activity of camelina oil FAEE molecules and its high viscosity. The results of the tests have shown that increasing of bio-additive content in fuel blend causes strengthening of boundary film of surface of friction pair. Camelina oil bio-additives positively affect lubrication properties of conventional jet fuels and may be used for improving anti-wear properties of jet fuels.

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References 1. Chuck, C.J., Donnelly, J.: The compatibility of potential bioderived fuels with Jet A-1 aviation kerosene. Appl. Energy 118, 83–91 (2014) 2. Iakovlieva, A., Boichenko, S., Lejda, K., Vovk, O., Kuszewski, H., Jakubowski, M.: Experimental study on antiwear properties for blends of jet fuel with bio-components derived from rapeseed oil. Eastern-Eur. J. Enterp. Technol. 5/8(77), 20–28 (2015) 3. Marunich, V.S., Melnichenko, O.I., Kharuta, V.S.: Passenger transportation: reliable information support. Int. Acad. J. Web Scholar 9(18), 31–35 (2017) 4. Yanovskii, L., Dmitrenko, V., Dubovkin, N., et al.: Fundumentals of aviation chemmotology. MATI, Moscow (2005) 5. Hu, J., Du, Z., Li, C., Min, E.: Study on the lubrication properties of biodiesel as fuel lubricity enhancers. Fuel 84, 1601–1606 (2005) 6. Nagornov, S.A., Dvoreckyi, D.S., Romancova, S.V., Tarov, V.P.: Technics and technologies of production and processing of plant oils. TGTU Publishing, Tambov (2010) 7. Dubovkin, I., Yanovskyi, L., Shigabaev, T., Galimov, F., Ivanov, V.: Engineering methods of analysis of physical-chemical and exploitation properties of fuels. Master-line, Kazan (2000) 8. Alves, S.M., Barros, B.S., Trajano, M.F., Ribeiro, K.S.B., Moura, E.: Tribological behavior of vegetable oil-based lubricants with nanoparticles of oxides in boundary lubrication conditions. Tribol. Int. 65, 28–36 (2013) 9. Bratkov, A.A., Seriogin, Ye.P., Gorenkov, A.F.: Chemmtology of jet fuels. Himiia, Moscow (1987) 10. Yakovleva, A., Boichenko, S.V., Lejda, K., Vovk, O.A., Kuszewski, Kh.: Antiwear properties of plant—mineral-based fuels for airbreathing jet engine. Chem. Technol. Fuels Oils 53(1), 1–9 (2017) 11. Trofimov, I.L.: Improvement of anti-wear properties of fuels and lubricants by electric field. Questions chem. Chem. Technol. 2, 54–58 (2013) 12. Aksenov, A.F., Chernova, K.S., Spirkin, V.G., Klirnov, S.G., Borodin, A.E., Belyanskii, V.P., Terekhin, V.I., Nekipelov, Y.G., Shepel’, A.Ya.: Effect of jet fuel chemical composition on antiwear properties. Chem. Technol. Fuels Oils 8(2), 133–137 (1972) 13. An American National Standard ASTM D1655 Standard Specification for Aviation Turbine Fuel 14. T-02U. Four-ball tester – operation manual. Instytute of Technology and Exploitation Publishing, Radom (2011) 15. Coordinating Research Council. https://crcao.org. Accessed 15 Oct 2018 16. Svyryd, M.M., Parashchanov, V.G., Onishchenko, A.V.: Complex for studying tribotechnical parameters of friction joint. Probl. Friction Wear 45, 204–209 (2006) 17. Xu, Y., Wang, Q., Hu, X., Li, C., Zhu, X.: Characterization of the lubricity of bio-oil/diesel fuel blends by high frequency reciprocating test rig. Energy 35(1), 283–287 (2010)

The Model for Evaluating Criteria Describing the Internal Safety of a Railway Trip by International Train Lijana Maskeliūnaitė(&) and Henrikas Sivilevičius Department of Mobile Machinery and Railway Transport, Vilnius Gediminas Technical University, Plytinės 27, 10105 Vilnius, Lithuania {lijana.maskeliunaite,henrikas.sivilevicius}@vgtu.lt

Abstract. The transport system must increase the mobility of the national population, gross domestic product (GDP) and remain environmentally friendly and safe. Rail transport is increasingly becoming popular for both long-distance freight and passengers. This trend is affected by an increase in safety travelling by train, which significantly improves the quality of the trip. The paper presents a mathematical model that allows calculating a share of the indicator for the quality of traveling by international train, which depends on the impact of criteria for internal safety in the carriage. The weights of eight sub-criteria for the main criteria falling into group D have been determined applying the Analytic Hierarchy Process (AHP) method, whereas their variables have been estimated using original formulas. The resolved numerical example admits that the introduced model is suitable and convenient to be employed in practice assessing the quality of the international train in a single number. The actual data on the international train Vilnius-Moscow indicating the adequacy of internal security measures have been used for the numerical example. Keywords: Railway transport safety
Criterion importance


Passenger
Quality of the trip
Internal

1 Introduction Railways are currently a widespread mode of transport because they provide not only safe but also an economical way to transport people and goods. Due to the high passenger and freight train capacity, as compared to other modes of transport, they offer a great solution to reduce traffic road congestion and indirectly reduce carbon dioxide emissions [1]. Significant successes in the improvement of railway systems have occurred due to the intensive development of science and technology. In the modern world, railway systems have acquired various forms such as the metro, city railways, express trains, etc. which is why they have become one of the most important modes of transport. All these improvements have led to an increase in the level of safety, speed of trains and comfort for passengers, these combination improvements to increasing today’s use of railway systems [2]. The safety of freight and passenger transportation by the railway network has a significant effect on growth in its attractiveness and competitiveness. Safety is one of © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 610–621, 2020. https://doi.org/10.1007/978-3-030-38666-5_64

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the most important ‘cornerstones’ of passenger and freight transportation [3]. With an increasing demand for high-performance and cost-effective railway transport, it is required that railway systems correspond two main criteria - fault tolerance and safety for freight and passenger traffic [4]. Often, service delays or hazardous situations on the railway arise from failures in railway point systems (RPS). To prevent railway interruptions, railway infrastructure operators use a condition monitoring system to detect early signs of RPS deterioration [4]. In an article to warn of a possible failure in the system, a methodology is presented for early detection of changes in the measurement of the current consumed by the RPS point working equipment (POE) engine. Since railroads play a crucial role in transport systems to ensure efficient and safe operation, risk assessment of the derailment of vehicles using reliable criteria is an important topic. Since risk assessment of derailment is a critical issue, the researchers attempted to identify and evaluate an effective derailment criterion. In the process of assessing the risk of derailment, the Nadal coefficient was widely adopted [5]. Authors [6] have proposed a wheel pair having an additional running track and counter-flange to provide an extra contact point in the horizontal plane considering the situation of lateral vibrations of the wheel pair relative to the track in order to ensure stability and to increase resistance against derailment when passing a curved part of the rail or in case of spring deflection of the rail as a result of force interaction. The design of the wheel pair with an additional counter-flange is covered by the Ukrainian utility model patent. Preventing railway transports from derailing is a crucial issue of the rail industry. In addition, an important point for reduction in the of derailment to limit the extent to which railway vehicles deviate from the track by formulating post-derailment measures [7]. The main goal of the Cheng and Hsu article [8] consists of exploring the derailment of an inclined railway vehicle on curved tracks experiencing the double influence of rail irregularities and an earthquake. The tipping vehicle is modeled as a system with 24 degrees of freedom with lateral, rotary and yaw movements of the trolley frames and taking into account the whole body. The results show that, overall, the derailment coefficient and unloading coefficient, estimated taking into account the earthquake under consideration, are greater than those obtained without taking into account the earthquake. Railways tracks are deteriorating due not only to train loads and due to environmental conditions. At the same time, growing demand for faster trains and a higher load increases the deterioration factor. Mechanical maintenance operations are regularly carried out to ensure safety, ride comfort and cost optimization throughout the life cycle [9]. Tamping and dynamic stabilization cause a more uniform load distribution, which reduces strain and increases acceleration in the rail and sleeper. Because of tamping and track dynamic stabilization, the contact surface between sleepers and ballast increases [9]. Due to the development of settlements in the backfill, the railway track in the transition zones between embankment bridges degrades more quickly. Therefore, this causes not only additional maintenance costs but also reduces comfort of passenger and can affect in transition zones the safety of trains [10]. Incorrect track geometry can affect the safe passage of rail traffic. Unevenly supported and unsupported sleepers make major contributions to the effect of track geometry deterioration. Therefore, maintenance activities on railways mostly directed towards the correction of track geometry [11]. Also in [12] presented that road geometry has a big impact on the

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overall emissions and energy consumption. Some roads directly connect destinations and directions, and some use winding and indirect routes. Xin et al. [13] introduced the use of gray system theory to predict geometric conditions for track structure, which contributes to effective maintenance decisions. This supports maintenance activities such as predicting and isolating geometric faults, extending the maintenance cycle, and implementing a predictive geometry maintenance policy. Gailienė et al. [14] in the article investigate of dual gauge track. This type of tracks construction has not been widely investigated. For present times geometrical parameters for the dual gauge track, the intensity of wheel-rail vibration, the impact of these parameters on wheel-rail interaction, and an effect on running safety with comfort have not been investigated at all. Caetano and Teixeira [15] propose a model for the deterioration the geometry on the railway track, which takes into account the uncertainties in the forecast by determining the reliability parameter of the geometry of the track. Turnouts are important units in the railway system and carry out a switching procedure that allows trains to switch between routes. The control of the geometry of the turnout path is necessary for planning maintenance and optimizing the design [16]. The presence of the rail system depends on the state of its infrastructure and rolling stock. To verify the rolling stock to prevent damage to the road due to faulty wheel infrastructure managers typically installed along roads control path [17]. Flat wheels can create at interface of wheel-rail strong impact forces, and they can cause high levels of local stresses, resulting in fatigue damage and breakdowns in various vehicle components and tracks [18]. When the vehicle passes through a curved track, the path of the wheel due to geometric parameters and the state of contact of the wheel with the rail will change, which may impair the interaction of the wheel with the rail. While the intensity of the vibration of the wheel and rail will affect the safety of movement and comfort [19]. The aim of Moreno-Ríos et al. [20] paper was to show that oil, using onboard lubricators, applied to the wheel flange altered the friction coefficient between the wheel and the rail and influenced acceleration and braking characteristics of trains on one of the metro lines in Mexico City [20]. Developed the basic principles of passive protection of high-speed passenger train concept in accidents on the railways of 1520 mm. Also, was developed, scientific methodology and mathematical model for the modeling of plastic deformation of the front elements of the locomotive, including a cab and frame energy-absorbing devices at longitudinal impact [21]. The fracture force, secondary impact velocity, acceleration curves, velocities, and deformation modes are calculated to compare the impact characteristics of a passenger car equipped with the proposed collision energy management system and a conventional passenger car system [22]. Holloway et al. [23] article presents the results from experiments testing the time what required for board or alight a train across different gap heights. Ensuring traffic safety is a major concern on roads and railways, with both of these infrastructures intersecting at level crossings. Therefore, constantly the problem of ensuring traffic safety at the intersection level remains really serious and therefore is often investigated. Although the number of deaths at railway crossings is only 2% of the total number of deaths on the roads, it makes up 20–30% of the total number of deaths on the railways [24]. Aleksić et al. [25] explored the accidents that took place in the railway system of Serbian Railways from 2006 to 2012 [25]. The analysis of the

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observed sample of 266 accidents that happened on railway crossings (RC) shows that the risk of accident occurrence is significantly higher at low temperatures (from −10 to 0 °C) and high air pressure (p > 1010 mbar) when risk makes 2.17, which is 2.41 times higher than standard (average) weather conditions. For complements the two previous versions, authors was wrote article [26], what addresses three problems arising from previously articles: (1) the reliability of highimpact design in scripts other than design conditions; (2) the correlation between the structural impact with passenger safety; (3) the characteristic the behavior of vehicle materials in train collisions. Because effective transfer service is always the prime concern of operators, stringent evaluation of transfer capacity is fundamental requirements for validating the design and ensuring efficient operations at big transport terminals [27]. The article [28] examines the impact of charging for access to railway infrastructure on the competitiveness of railway transport in selected European countries. The article concentrated on the development of indicators showing competition in the market of railway transport and included volume of traffic, throughput and number of trains of private railway operators compared to national. According to [29] nowadays public transport systems have been targets in several terrorist attacks, which have resulted in tight security measures worldwide. This paper uses a stated choice experiment to quantify individual trade-offs between privacy and security within the real-life context, namely rail travel in the UK. Using a nationwide sample, empirical analysis identifies the importance of improvements in security infrastructure and identifies areas of concern with respect to confidentiality and control of free travel factors. The article [30] describes the approach that forms the risk management for the railways of Great Britain (Great Britain), which inevitably leads to intelligent databased security solutions and thereby explains the increased interest in databased security solutions. Serious accident prevention is a key focus of all railway partners. Train accidents are devastating, costly and cause human suffering that damages the railway industry as a whole. The purpose of paper [31] is to review best practices and recommendations for the prevention of railway encroachments and vandalism, as well as a brief overview of the most promising preventive measures related to the human factor, namely: joint measures, law enforcement, staff training, public education and environmental measures, which can affect human behavior. Crawford et al. [32] presents the difficulties involved in integrating the human factor into socio-technical systems, such as railway dispatch systems, and talks about how design standards that focus on specific areas of leadership and analytical tools for the human factor can contribute to the integration of the human factor (HFI). In paper [33] presents the methods what analysing why passenger chooses travelling by train as an alternative to using flying transport. Rail traffic safety is a set of railway traffic characteristics showing how road users and rolling stock are protected from accidents and their consequences. Railway safety can be divided into two categories: external and internal. This article assesses the internal safety of the railway trip, i.e. creating favourable driving conditions for passengers in order to avoid accidents on the train (in the carriage) or making the consequences of the accident minimal. The purpose of this paper is to propose an original

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multicriterial mathematical model for evaluating the weights of eight criteria describing the safety of a trip by rail, as well as their impact on the comprehensive quality index (CQI), and on confirming the results using a study of CQI numerical calculations for the international train “Vilnius – Moscow”.

2 The Model for Internal Safety on the Train The quality of travel by train (QTT) is described by both qualitative and quantitative criteria. It should be convenient to quantitatively evaluate the significance of all criteria for the QTT by a single number. The significance of particular criteria differs to some extent. In the paper by Maskeliunaite, Sivilevicius, 49 QTT criteria falling into four groups A, B, C and D (Fig. 1) are considered [34].

CRITERIA FOR THE QUALITY OF THE RAILWAY TRIP A. Criteria describing the elements of the train and the technical state of the railway track B. Criteria describing planning and technology of the railway trip C. Criteria describing the cost of the trip and provided services D. Criteria describing the safety of the railway trip D1.

Availability of fire safety equipment and its condition

D2.

Availability of thefirst medical aid

D3.

Possibility of calling an ambulance

D4.

Operational state of axle-box overheating and the firealarm system

D5.

Availability of emergency exits

D6.

Condition of hand-rails, stairs, tambours, doors and locks

D7.

Operational state of the hand brake and emergency brakes

D8.

Possibility of calling the police

presented in this work

Fig. 1. The components of quality criteria for groups A, B, C and D describing the quality of the railway trip.

Their average weights are determined using the expert evaluation method. The weights of 8 criteria falling into group D and describing the safety of the railway trip were obtained from the survey of experts when three categories of respondents – passengers (P) and experts, including the service staff of the train (ST) and the administration staff (AS) of the joint-stock company ‘Lithuanian Railways’ (AB “Lietuvos geležinkeliai” – “LG”) provided their judgements.

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The model for calculating criteria describing the safety of the railway trip based on
Dj (showing the estimates of the mean weight Z
D and the mean weight of 8 criteria Q significance of criteria falling in group D elicited from all three categories of respondents and experts) is expressed by the equation
D1  xD1 þ Q
D2  xD2 þ . . . þ Q
D8  xD8 Þ; KD ¼ Z
D ðQ

ð1Þ

where KD is the comprehensive quality index (CQI) of the international train (ranging
D is the mean weight reflecting the respondent and expert estimates of the from 0 to1); Z

D1 , …, Q
Dm denote the significance of criteria for group D Z
D ¼ 0:2860 [35]; Q values of the mean weight (Fig. 2) of the j-th criterion for group D (1, …, m) determined by the expert evaluation method [36, 37] xD1, …, xDm are the variables of the j-th criterion for group D (1, …, m) the estimates of which are used for determining the value of the real criterion ranging from 0 to 1. Multi-criteria KD [34] describing criteria related to the condition for the safety of the railway trip are calculated by additive Eq. 2. nP car nmeasures P





FFMf FFMmax c

FAMf
D3
Af þQ FAMmax Amax   nP nP car  car  EEf CMTCf   EEmax c CMTCmax c ð0:92
Tambierair þ 45Þ  Tf
D5
c¼1
D4

D6
c¼1 þQ þQ þQ ð0:92
Tambierair þ 45Þ  Tambierair ncar ncar   nP car nbraking P TMBf  TMBmax c¼1 b¼1
D7

D8
POCf ; þQ þQ ncar
nbraking POCmax


D1
c¼1 m¼1 KD ¼ Z
D
ðQ ncar
nmeasures


D2
þQ

ð2Þ where KD is the comprehensive quality index (CQI) of the international train (ranging from 0 to 1); Z
D is the mean weight reflecting the respondent and expert estimates of
Dm denote the values of the mean
D1 , …, Q the significance of criteria for group D; Q weight of the j-th criterion for group D (1, …, m) determined by the expert evaluation method; FFMf, FFMmax – the factual and maximum scores of the types of fire extinguishing media in the carriage (FEf – the factual score of the availability and condition of fire extinguishers in carriage c (0, 1 or 2 points)); FEmax – the maximum possible score of the availability and condition of fire extinguishers in carriage c (2 points); OSPf – the score of the availability and condition of the OSP-1 (automatic powder extinguisher) in carriage c (0, 1 or 2 points); OSPmax – the maximum possible score of the availability and condition of the OSP-1 in carriage c (2 points); IIPf – the score of supplying carriage c with manufactured PPE (personal protective equipment) and its condition (0, 1 or 2 points); IIPmax – the maximum possible score of supplying carriage c with manufactured PPE (2 points); FASf – the score of the availability and condition of the FAS (automatic fire alarm system) in carriage c (0, 1 or 2 points); FASmax – the highest possible score of the availability and condition of the FAS in the carriage

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(2 points); FFEf – the score of the availability and condition of automatic FFE (aerosol fire extinguishing equipment) in carriage c (0, 1 or 2 points); FFEmax – the highest possible score of the availability and condition of automatic FFE in the carriage (2 points); FAMf – the factual score of the availability of first aid measures (0, 1 or 2 points); FAMmax – the maximum possible score of the availability of first aid measures (2 points); Af – the score of the availability of medical emergency in the train (0, 1 or 2 points); Amax – the maximum possible score of the availability of medical emergency in the train (2 points); Tf – the temperature of the measured ABAN (axle-box and axle neck), °C; Tambient air – the temperature of ambient air on the measured site (station), ° C; EEf – the score of emergency exits in carriage c (0, 1 or 2 points); EEmax – the maximum possible score of emergency exits in carriage c (2 points); CMTCf – the scores of the efficiency of handrails, steps, doors, locks and tambours in the carriage c of the train (0, 1, 2, 3 or 4 points); CMTCmax – the maximum possible score of the efficiency of handrails, steps, doors, locks and tambours in the carriage (4 points); TBMf, TBMmax – the factual and maximum scores of the types of train braking measures; HBf – the score of the condition and action of the hand brake in carriage c (0, 1 or 2 points); HBmax – the maximum possible score of the condition and action of the hand brake (2 points); EBCf – the score of the condition of emergency brake cocks in carriage c (0, 1, 2, 3 or 4 points); EBCf – the maximum possible score of the condition of emergency brake cocks in carriage c (4 points); ncar – the number of carriages (c = 1, 2, …, V); nmeasures – the number of the types of fire extinguishing media in the carriage, (m = 1, 2, …, nmeasures); nbraking – the number of the types of braking measures in the carriage of the train, (b = 1, 2, …, b); POCf – the score of the possibility of calling the police (0, 1 or 2 points); POCmax – the maximum possible score of calling the police (2 points). Based on the considered model, real research data and the allowable or best values of criterion 8, the significance of criteria for group D evaluating the quality of passenger transportation by train using a single value may be obtained.
Dj of the j-th criterion for group D determined by the AHP Mean weight values Q method are presented in Fig. 2.

0.2 0.15

0.1726

0.1514 0.0957

0.1

0.1087

0.1504

0.1297

0.0963

0.0953

0.05 0 1

2

3

4 5 6 Number of criterion group D

7

8


Dj of the j-th criterion for group D determined by the AHP Fig. 2. Mean weight values Q method.

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Using the formulas suggested in the paper, all CQI components (8 criteria) and their significance may be calculated based on real data taken from standards, technical specifications and other reliable sources. Testing was performed on the train ‘Vilnius– Moscow’.

3 Practical Application of the Model The quality level of criteria for group D and respective xDj value based on real data are presented in Table 1. The quality level denoted by the estimate of variable xDj is equal to 1 when it is based on the highest values of real data, is equal to 0.5 when based on the average values and equal to 0 when based on the lowest values of data. Using Eq. (2), the index KD of criteria describing the safety of the railway trip is calculated as follows: KD ¼ 0:286
ð0:1514
0:971 þ 0:0957
0:50 þ 0:1087
0:50 þ 0:1726
1 þ 0:1297
1 þ 0:0953
1 þ 0:1504
1 þ 0:0963
0:50Þ ¼ 0:242: The index referring to the criteria describing the safety of the railway trip is equal to KD = 0.242. Multi-criterion indicator K for the international train is calculated according to the formula K ¼ KA þ KB þ KC þ KD ;

ð3Þ

where KA, KB, KC, KD – multi-criteria indicators for quality criteria falling into groups A, B, C and D respectively. Table 1. The quality level of criteria for group D and the respective value of variable xDj based on real data. Variables xDj of criteria xD1

xD2 xD3 xD4 xD5 xD6 xD7 xD8

The value of the component FEf ¼ 2; FEmax ¼ 2; OSPf ¼ 2 OSPmax ¼ 2; IIPf ¼ 2; IIPmax ¼ 2 FASf ¼ 2ð1; 2; . . .; 6Þ; FASf ¼ 0ð7Þ UPSmax ¼ 2; FFEf ¼ 2 ð1; 2; . . .; 7Þ FFEmax ¼ 2; ncar ¼ 7; nmeasures ¼ 5 FAMf ¼ 1; FAMmax ¼ 2 Af ¼ 1; Amax ¼ 2 Tf ¼ 22; Tambientair ¼ 22 EEf ¼ 2; EEmax ¼ 2ð1; 2; . . .; 7Þ; ncar ¼ 7 CMTCf ¼ 4; CMTCmax ¼ 4 ð1; 2; . . .; 7Þ; ncar ¼ 7 HBf ¼ 2; HBmax ¼ 2 ð1; 2; . . .; 7Þ; EBCf ¼ 4; EBCmax ¼ 4ð1; 2; . . .; 7Þ; ncar ¼ 7; nbraking ¼ 2 POCf ¼ 1; POCmax ¼ 2

Note: (for the c-th passenger carriage*)

Calculated value xDj 0.971

0.50 0.50 1 1 1 1 0.50

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The effect of criteria for groups A, B and C on CQI K has been evaluated applying the additive model and KA = 0.1341 [38]; KB = 0.242 [39] has been obtained. The effect of criteria for group C on CQI K can be evaluated employing other additive models that will be described in further publications.

4 Conclusions The suggested multi-criteria model allows the accurate evaluation of the quality of travelling by train and expresses it by a single value. The estimate of KD calculated based on the values of real parameters allows the authors to state that the considered mathematical models are acceptable and can be used in practice. The significance of criteria describing the safety of the railway trip for comprehensive quality index KD may be assessed by determining variables xDj and using them in the proposed mathematical model. The highest quality level defined using real data has been obtained for criteria D4 (operational state of axle-box overheating and the fire alarm system), D5 (availability of emergency exits), D6 (condition of hand-rails, stairs, tambours, doors and lock) and D7 (operational state of the hand brake and emergency brakes) (xD4, xD5, xD6, xD7 = 1). The average quality level found in D2 (availability of first medical aid), D3 (possibility of calling an ambulance) and D8 (possibility of calling the police) (xD2, xD3, xD8 = 0.50) has been based on real data.

References 1. Alexandrou, G., Kouroussis, G., Verlinden, O.: A comprehensive prediction model for vehicle/track/soil dynamic response dueto wheel flats. Proc. Inst. Mech. Eng. Part F: J. Rail Rapid Transit 230(4), 1088–1104 (2016). https://doi.org/10.1177/0954409715576015 2. Zakeri, J.A., Esmaeili, M., Kasraei, A., Bakhtiary, A.: A numerical investigation on the lateral resistance of frictional sleepers in ballasted railway tracks. Proc. Inst. Mech. Eng. Part F: J. Rail Rapid Transit 230(2), 440–449 (2016). https://doi.org/10.1177/0954409714543507 3. Bureika, G., Komaisko, M., Jastremskas, V.: Modelling the ranking of Lithuanian railways level crossing by safety level. Transp. Probl. 12, 11–22 (2017). https://doi.org/10.20858/tp. 2017.12.se.1 4. Vileiniskis, M., Remenyte-Prescott, R., Rama, D.: A fault detection method for railway point systems. Proc. Inst. Mech. Eng. Part F: J. Rail and Rapid Transit 230(3), 852–865 (2016). https://doi.org/10.1177/0954409714567487 5. Kuo, C.-M., Lin, C.-C.: Analysis of derailment criteria. Proc. Inst. Mech. Eng. Part F: J. Rail and Rapid Transit 230(4), 1158–1163 (2016). https://doi.org/10.1177/0954409715583692 6. Osenin, Y.Iv, Degtyareva, L., Osenina, G., Sergienko, O., Chesnokov, A.: Using a wheel pair with a counter-flange to prevent derailment. Transp. Probl. Problemy Transportu 12(2), 13–18 (2017) 7. Wu, X., Chi, M., Gao, H., Zhang, D., Zeng, J., Wu, P., Zhu, M.: The study of postderailment measures to limiting the extent of a derailment. Proc. Inst. Mech. Eng. Part F: J. Rail and Rapid Transit 230(1), 64–76 (2016). https://doi.org/10.1177/0954409714526586

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Analysis of Existing Train Lines and International Railway Transport Corridors of Ukraine Evgeniya Ugnenko1(&) , Anna Shevchenko1 , Oleksander Matviienko2 , Anatoliy Maliavin1 , Gintas Viselga3 , and Vytautas Turla3 1

Ukrainian State University of Railway Transport, Feierbakh Square 7, 61050 Kharkiv, Ukraine [email protected], [email protected], [email protected] 2 Engineering Systems “El-Term”, Vosstaniya Square 7/8, 61000 Kharkov, Ukraine [email protected] 3 Vilnius Gediminas Technical University, J. Basanavičiaus str. 28, 03224 Vilnius, Lithuania {gintas.viselga,vytautas.turla}@vgtu.lt

Abstract. In this paper, the characteristics of international transport corridors (ITC) with common technical parameters and ensuring the application of a unified transportation technology as the basis for the integration of national transport systems into the world transport system are given. The development of ITC and transit traffic may become a very inspiring factor for Ukraine to revitalize its position in the global economy. The question is to reach the required level of cooperation, at the appropriate time, which, apparently, has already come. The concept of the international transport corridor is one of the key determinants and requires definition, as in various works, this term refers to somewhat different concepts. The scenarios having different impact on infrastructure, networks, rolling stock, and financial problems are overviewed. Examples of high-speed rail network (HSR) routes for private traffic are presented. Due to the dramatic reduction in travel time compared to the current duration, the travel time of the HSR will be very competitive. This paper presents the duration of trips from Kiev, Kharkov, Odessa, Lviv and the Dnieper. Keywords: High-speed rail
Pan-European transport corridors
International transport corridors
Railway of ukraine
Rolling stock
High speed lines

1 Introduction In the matter of international cooperation and deepening of production cooperation, the leading role belongs to the formation of a network of international transport corridors. She devotes a special place to solving transport problems related to the expansion of interstate transport-economic, cultural and other ties, with the creation of international © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 622–632, 2020. https://doi.org/10.1007/978-3-030-38666-5_65

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transport infrastructure, which has common technical parameters and provides the application of a single technology of transportation as the basis of integration of national transport systems in the world transport system (Fig. 1) [1].

Fig. 1. Map of the ten Pan-European transport corridors. The corridors variously encompass road, rail and waterway routes.

Transport corridors for transit traffic on the territory of Ukraine pass through the regions rich in minerals and promising in terms of their development. Transit of Ukrainian territory is a transit of a single territory, which has uniform laws, including customs legislation, while competitors have to seek consensus among the interests of different sovereign states. The development of ITC and transit traffic may become a very inspiring factor for Ukraine to revitalize its position in the global economy. The question is to reach the required level of cooperation, at the appropriate time, which, apparently, has already come. The concept of the international transport corridor is one of the key determinants of this work and requires definition, as in different works, this term means somewhat

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different concepts. In Wikipedia, the concept of international transport corridors – means transport arteries and a set of different types of transport, which provide significant transportation of goods and passengers in the areas of their greatest concentration. Transport corridors act as blood vessels in global integration processes. In Russia, the concept of the international transport corridor is often interpreted as being simplified, as the presence of its own rolling capacity. However, initially, the idea of any transport corridor is to concentrate transport, freight and passenger streams on highways that have the maximum throughput and high level of infrastructure, which contributes to accelerating freight and passenger transportation, reducing their cost through the emergence of a scale effect and the emergence of synergistic effects for account of the interaction of several types of transport. In business circles, ITC means a set of unified road and cargo turnover infrastructure, unified cargo units (20 and 40 foot containers, trailers, body modifiers), organizational-legal and institutional mechanisms, mutual preferences of territorial economic entities, etc., which provides cargo and investment attractiveness of this type in comparison with other possible schemes. In one of the well-known documents [10], ITCs are characterized as regional incentives – impulses, and regional and local economies acquire through investments. According to the same document, for the spatial planning of regional incentives, special transport nodes are of particular importance – such as the section of highways; large stations; airports; centers of cargo carriage; river ports. Their influence extends beyond the adjoining territory, covering the whole region [2, 3]. From the technological point of view, international transport corridors are high-tech transport systems, which concentrate on the general directions of public transport and telecommunications. From an economic point of view, the UN Economic Commission for Europe has identified the MTC as part of the national or international transport system that provides significant international freight and passenger transportation between individual geographical areas, including rolling stock and stationary devices of all modes of transport working in this direction, and also a set of technological, organizational and legal conditions for the implementation of these transportation. The main difference between the transit trading corridor is the introduction in addition to the aforementioned favorable customs, tax, administrative regimes and the provision of a set of additional logistics services for the development of trade between regions or countries that connects this transport corridor [4, 5]. Developing corridors are called to play a system-forming role in the economic and social development of the territories in which they pass. Their creation is tied to projects of development of branches of economy and social sphere of the respective regions. Establishing the necessary conditions for the operation of the ITC in Ukraine should include the improvement of the national regulatory framework and the provision of international support. It is necessary to improve the legislative and regulatory acts regulating the issues of activity of transport enterprises, customs control bodies, border guard, sanitary and other services, interaction between them and other participants of the transport process, harmonization of Ukrainian legislation with international legal acts regulating international transportation and the operation of ITC, as well as ensuring the interests of the Ukrainian side in the formation and development of ITC [6].

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As a result of this work, in particular, there should be harmonized rules for the use of transport systems of Ukraine with international requirements, defined conditions for the use of Ukrainian transport communications by foreign carriers, enhanced coordination of the various types of transport in the organization of cargo transportation in a mixed message, created favorable conditions for the work of domestic operators Transportation in the main lines of the ITC, brought in line with international requirements for the rolling stock of Ukrainian transports sports companies, increased coordination of actions of state transport management bodies, customs and border services, transport and forwarding enterprises when crossing the vehicles of the border of Ukraine, which will reduce the time for implementation of administrative, customs and other operations, raised to the level of international requirements for ensuring road safety and reducing the harmful effects of transport on the environment, to create an integrated with the international system of electronic document management, to improve the system of the country ends during the transport of goods and passengers in international traffic [7, 8]. The Lithuanian-Ukrainian Intergovernmental Commission approved the cooperation between the countries in transport infrastructure projects, emphasized the importance of improving the economic relations and business environment of the countries [9].

2 Methodology The track gauge in Ukraine differs from the standard gauge on the international transport network. One of the most important issues in the implementation of the network is the choice of gauges for the Ukrainian high-speed networks – 1520 mm (CIS) or 1435 mm (standard for international transport corridors). Three scenarios are possible for high-speed lines: CIS track gauge application (1520 mm), international transport corridor network gauge application (1435 mm) and rolling stock adapted for both types of track (standard UIC gauge for high-speed lines and standard gauge for CIS countries for railways due to the variable wheel width). The impact of each scenario on infrastructure, networks, rolling stock, and financial problems differs. The results of different Ukrainian high-speed network scenarios are presented below: 1. Network with gauge of 1520 mm, which would be no compatibility with European high-speed lines. The total cost of research, rolling stock validation, route design and construction work is estimated at EUR 100 million. It would take 3–5 years to develop a new high-speed line composition [11]; 2. Network with 1435 mm gauge. There is no compatibility with either the traditional Ukrainian railway network or the CIS high speed networks (with a gauge of 1520 mm) [11]. Minimum installation costs for existing stations compared to the total cost of this project; 3. Rolling stock adapted for two types of track. A new type of rolling stock is designed with automatically changing pairs of wheels. Such a design would mean increased maintenance costs and a lengthy approval process for the solution. The total fixed

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costs of the rolling stock system study and validation amounts for EUR 50 million [11]. As in the first scenario, the designing of the new system would take between 3 and 5 years. According to the information provided, the choice of gauge for the Ukrainian highspeed train network is more of an operational, financial and political rather than a technical issue [11]. The proposed high-speed rail network for Ukraine should be implemented in stages. A program for the development of high-speed lines should be drawn up, giving priority to the introduction of these lines. The following aspects should be analyzed to determine whether it is appropriate to continue working on any of the components: political criteria, environmental impact, socio-economic aspects and financial profit. This study showed that the entire network is economically viable [11]. It is therefore recommended that an additional project feasibility study be carried out. Such a study is intended to be a full-scale improvement.

3 Research Results In order to evaluate the alternatives, the optimality criterion must be chosen. In modern conditions, the integral effect is considered to be the criterion of optimality Eint, which is determined by the formula [11]: Eint ¼

X

ðRt  Kt Þgt ;

ð1Þ

where Rt – result for the year; Kt – outgoings for the year; ηt – the discount coefficient is determined by the formula [11]: gt ¼

1 ; ð1 þ E Þt

ð2Þ

where E – discount norm for normative documents; t – period number. Using the optimality criterion (1), the passive search method with a small uncertainty interval can be used to find the optimal variant [11]. With the many options available to find the optimal solution, directional search should be applied. There are many application methods, and they have their advantages and disadvantages. Today 10 high-speed Korean-produced Intercity “Hyundai” trains and two “Skoda” trains operate in Ukraine. These trains have a maximum speed of 160 km/h [5, 11]. The following are examples of high-speed railway network routes for private traffic. Due to the dramatic reduction in travel time compared to the current duration, the travel time of the HSR will be very competitive. This paper presents the duration of trips from Kiev, Kharkov, Odessa, Lviv and the Dnieper.

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This information is presented for illustrative purposes only. In the future, it is necessary to carry out a detailed study of each line, taking into account all the characteristics of the infrastructure, subsystems, rolling stock and operation. The proposed high-speed rail network for Ukraine will be introduced over a period of 30 to 40 years, with the possible launch of the first project in operation in 2020 or 2025. In the study, the base speed was taken as 350 km/h. The duration of trips from Kiev is presented in the following Table 1. Table 1. The duration of travel from Kiev. HSR

Existing at the moment the duration 350 km/h 2018 year 160 km/h Kiev Poltava 01:10 07:00 03:07 Kharkov 01:35 09:30 04:45 Dnieper 01:35 09:00 05:45 Mariupol 02:55 18:00 – Krivoy Rog 02:30 09:00 – Zaporizhia 02:10 10:30 07:18 Melitopol 02:40 12:00 – Nikolaev 01:35 10:00 06:27 Odessa 01:50 11:00 07:15 Kherson 02:00 12:30 07:13 Vinnitsa 01:00 03:30 02:19 Khmelnitsky 01:30 07:00 03:57 Ternopil 02:00 08:00 05:22 Lviv 01:50 11:00 5:09

The duration of trips from Kharkov is presented in the following Table 2. Table 2. The duration of travel from Kharkov. HSR

Existing at the moment the duration 350 km/h 2018 year 160 km/h Kharkov Kiev 01:35 09:30 04:45 Poltava 00:35 02:54 01:36 Dnieper 01:10 05:07 – Zaporizhia 01:35 04:46 – Melitopol 02:05 06:16 – Odessa 02:03 11:21 – Lviv 03:30 24:20 12:55

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The duration of trips from Odessa is presented in the following Table 3. Table 3. The duration of travel from Odessa. HSR

Existing at the moment the duration 350 km/h 2018 year 160 km/h Odessa Kiev 01:50 11:00 07:15 Kharkov 03:00 13:00 – Dnieper 01:50 11:03 – Mariupol 03:15 20:27 – Krivoy Rog 01:15 12:23 – Nikolaev 00:35 04:30 – Kherson 01:00 05:23 – Lviv 03:30 12:28 –

The duration of trips from Lviv is presented in the following Table 4. Table 4. The duration of travel from Lviv. HSR

Existing at the moment the duration 350 km/h 2018 year 160 km/h Lviv Kiev 01:50 12:22 5:09 Poltava 03:40 21:30 – Kharkov 03:30 24:00 – Dnieper 03:30 18:10 – Nikolaev 02:50 21:30 – Odessa 03:30 12:13 – Vinnitsa 01:15 07:09 04:35 Khmelnitsky 01:05 04:32 02:57 Ternopil 00:35 02:05 01:29

The duration of trips from the Dnieper is presented in the following Table 5. Since the duration of travel by high-speed trains is very small, many trips will be made during the daytime. Based on international experience, high-speed traffic expects private success. To meet demand, it is necessary to ensure a high frequency of transportation. For distant lines, it is necessary to provide a high frequency of movement, for example: 1. During periods of highest load: at least 1 train every 30 min; 2. The rest of the time: 1 train per hour.

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During the normal working day, high-speed trains can operate from 6:00 (first departure) to 24:00 (last arrival) with 2 h “peak” in the morning and 2 h – in the evening. For each line with a trip duration of 1 h, you need to use 21 trains, with a trip duration of 2 h – 20 trains and with a trip duration of 3 h – 19 trains. Following this rule, it will be possible to use a different number of trains on the 34 lines proposed earlier. In total, we would get 201 trains a day for each line. As a result, without changes in lines, we would have such a number of trains for the following important lines from Kiev presented in Table 6. Table 5. The duration of travel from Dnieper. HSR

Existing at the moment the duration 350 km/h 2018 year 160 km/h Dnieper Kiev 01:35 08:28 05:45 Poltava 00:35 09:32 – Kharkov 01:10 05:57 – Mariupol 01:25 10:42 – Zaporizhia 00:30 02:15 01:23 Melitopol 01:00 03:54 – Nikolaev 01:20 13:43 – Odessa 01:50 18:13 – Lviv 03:30 18:09 –

Table 6. Frequency of high-speed trains. Frequency of high speed trains for each line Kiev Poltava 27 Kharkov 30 Dnieper 30 Mariupol 9 Krivoy Rog 6 Zaporizhia 6 Melitopol 6 Nikolaev 24 Odessa 24 Kherson 9 Vinnitsa 15 Khmelnitsky 12 Ternopil 12 Lviv 30

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If we assume that 402 trains with a capacity of 545 seats (as, for example, a twotiered TGV) will be used per day, we will receive 76 million places-km every day. If we take the dynamic coefficient in the amount of 65% of the train load, we will get 49.2 million passenger-kilometers per day, provided that all the trains run in the same train. Thus, the daily demand for the transportation of HSR will amount to 237,000 passengers, and the average travel distance per passenger will be 415 km. Every year we would have 87 million passengers and 35 billion passenger-kilometers. Such a volume of demand in 2030 or 2040 should also be compared with the volume of intercity railway traffic in Ukraine. This comparison is presented in Fig. 2. In 30–40 years, domestic demand for passenger transportation by high-speed rail (which are characterized by short travel times and high frequency of train traffic) in Ukraine will certainly reach this level.

Fig. 2. The volume of rail traffic in Ukraine for the years 1990–2018.

Taking into account the fact that the theoretical load of the high-speed line is 20 trains per hour with an interval of 3 min, 15 trains per hour can be used for private service. In the event that demand is higher than that considered in this study, you can use a larger number of trains or twin trains. It can be expected that as a result of the implementation of the high-speed railway project, apart from the existing traffic, we will get two effects: 1. The deviation of traffic from competing modes of transport; 2. Encouragement of additional transportation: stimulated transport is an additional transport that would not have arisen if nothing had been undertaken.

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In the future, a detailed study with mathematical modeling of traffic volumes for the high-speed railway project will be required. Rolling stock, which is necessary to fulfill the proposed plan of operation, will be 333 trains under the following conditions: capacity: 545 seats (corresponds to the capacity of a two-tier train consisting of 8 cars with a length of 200 m); coefficient of coupling: 1.5; the reserve ratio for the maintenance, operation, disaster recovery: 10%. With the estimated number of trains used for private traffic, we get the following statistics on the services of the Eastern Railway: 402 turnover per day (only for 2 lines); 278 thousand train-km per day (only for 2 lines); 1,062 train-hours per day (only for 2 lines); average turnover distance: 691 km; average round trip time: 2:38; average driving speed: 262 km/h; daily demand for HSR: 356,000 passengers; annual demand: 130 million passengers and 54 billion pass-km; rolling stock: 333 trains with a capacity of 545 seats in the composition.

4 Conclusions In order to reduce the time of tiring travel by train, high-speed railway lines are created, which are known to be extremely privately successful. The new opportunity to travel by high-speed trains revolutionizes land transport, revives passenger railway transport and competes airlines. The high-speed railway is also favorable in the field of ecology. The railway is also the most reliable (safe) mode of transport. HSR has a positive impact on economic activities such as trade, tourism, hospitality sector and other services. Also for urban development, real estate, employment, etc. From the success of the development of high-speed rail, the following conclusions can be made: Countries that implement high-speed rail systems have significant government indicators and the HSR is the basis of these indicators. These countries were prepared to finance the huge investment costs arising, believing in their vision of these projects. In Europe, interoperable high-speed rail network is a factor uniting the countries of the European Union. In Japan, HSR is the main factor supporting development. In particular, Ukraine needs to put into operation a construction phase based on Derzhstat passenger flow analysis in order to connect Lviv with Kiev.

References 1. Regulations on carrying out planned preventive repair and road works on the railways of Ukraine. Ministry Transport of Ukraine (2004) 2. Kurhan, M.B., Kurhan, D.M.: Theoretical basis for the introduction of high-speed trains in Ukraineю DNUZT, Dnipro (2016) 3. Korzhenevich, I.P.: New possibilities for designing plan redevelopment and correction of curves when using the program RWPlan 1.2. Railway Transp. Ukraine 5, 79–82 (2015) 4. Guidance on the main issues of the arrangement and maintenance of the Railroad. Transp. Ukraine (2007)

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5. Shevchenko, A.A.: Increase the trains speed on the raylways of Ukraine. In: 80th International Scientific and Technical Conference, Ukraine, vol. 177, 112–113 (2018) 6. Cadena, P.C.B., Magro, J.M.V.: Setting the weights of sustainability criteria for the appraisal of transport projects. Transport 30(3), 298–306 (2015) 7. Kirpa, G.M.: Integration of Ukraine’s railway transport into the European transport system. DNUZT, Dnipro (2004) 8. Kurhan, M.B., Kurhan, D.M.: Science and transport progress. Bull. Dnipropetrovsk Natl. Univ. Railway Transp. 6(72), 40–48 (2017) 9. Lithuania and Ukraine to be connected by new flights and train routes. My Government, 17 July 2018. https://sumin.lrv.lt/en/news/lithuania-and-ukraine-to-be-connected-by-new-flightsand-train-routes. Accessed 30 Mar 2019 10. Guiding Principles of Sustainable Spatial Development of the European Continent. In: 12th CEMAT Conference, Hannover, 7–8 September (2000) 11. Shevchenko, A., Matviienko, O., Lyuty, V., Manuylenko, V., Pavliuchenkov, M.: Ways of introduction of the high-speed movement of passenger trains in Ukraine. In: MATEC Web of Conferences, Transbud 2018, Ukraine, vol. 230, pp. 1–9 (2018). https://doi.org/10.1051/ matecconf/201823001014. Accessed 30 Mar 2019

Control Technology of Railway Traffic Safety: A System Approach and Digitalization Valerii Samsonkin(&)

and Oleksii Goretskyi

State University of Infrastructure and Technology, Kyrylivska Str. 9, Kyiv 04071, Ukraine [email protected]

Abstract. The article analyzes the main regulatory documents governing the safety management of railway transport in Ukraine and the EU. It has been revealed that in the safety management system there is no the control algorithm. The idea of the control algorithm uses the Statistical Regularity Method for Safety Management. The basic principles of the Method are “bottleneck”, norms of behavior, tolerance, statistical regularity, the final result of the transport system activity. The algorithm uses traditional statistics of safety violations. As the bottleneck, the most important background (the fundamental cause) in ensuring the transportation process is considered. A procedure of support of the management decision development to ensure the required level of safety is proposed. A specific set of actions that lead to the formation of a management decision is proposed. The use of norms of behavior adapts the management process to existing traditions in the organization. The control algorithm will help to reduce the impact of the human. Conclusions: 1. The proposed safety control algorithm allows not to provide safety in general, but to focus on “bottlenecks”. This makes the management process transparent and directional, and financing efficient. 2. Conditions have been created for introducing digitalization into the process of safety management in transport. 3. Use of the system approach will allow estimating integrally failures in the transportation process and moving to the concept of eliminating bottlenecks. 4. It is possible to apply the proposed control algorithm in other modes of transport, safety directions and technologies. Keywords: System approach


Cause background
Management decision

1 Introduction Creation of intelligent, safe and user-friendly mobility systems is one of the priority areas for the development of transport around the world. Rail transport is no exception to this process. The emergence of INDUSTRY 4.0, RAILWAY 4.0 and DIGITAL RAILWAY concepts has become a notable phenomenon of adaptation to the new conditions of the digital economy. Meanwhile, the radical advancement in the business environment, promoted by information and communication technology (ICT), requires that traditional business models and strategies of railways be updated. To this should be prepared and develop models and concepts of processes in new conditions. © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 633–638, 2020. https://doi.org/10.1007/978-3-030-38666-5_66

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A deep understanding of the concept of digital transformation is of paramount importance in the development of rail transport in the New Economy. What has been said above refers to such a classical and at the same time conservative function of railway transport as traffic safety. Many safety principles have evolved over 50 years ago and have not changed much. This also applies to the aspect of safety management. In recent years, developments have emerged that characterize a new approach to rail safety technology [1–4]. The main technologies and solutions that have accelerated digital transformations in the railway sector in recent years: Internet of Things (IoT), Cloud Computing, Big Data Analytics (BDA), Automation and Robotics, Artificial Intelligence.

2 Problem Definition We have analyzed the content of the main documents that are devoted to the safety management system in railway transport in the EU and Ukraine. They are the Directive 2004/49/EU [5] – for the EU, and “Polozhennya pro sistemu upravlinnya bezpekoyu ruhu poyizdiv u Derzhavniy administratsiyi zaliznichnogo transportu Ukrayini” (Regulation on the system of safety management of trains to the State Administration of Railway Transport of Ukraine) [6] and the Ukrainian version of Directive 2004/49/EU – for Ukraine. All necessary concepts of control theory there are in [5, 6] – the object and the subject of management, management targets, principles and methods, differentiate the management and monitoring of safety. There is no only concept of “online control”. There is the concept of managerial decisions to ensure traffic safety in documents [5, 6] ([5], p. 37). But “subjects of management – personnel, functional offices, structural units that influence the management system in order to ensure its functioning” these are people-experts. And therefore the control algorithm is the decisions and actions of these people. But why is there no allusion about expert systems, artificial intelligence, safety databases (there are a lot of them in railway transport)? There are no sections about digital technologies. The absence of a scientifically based and clearly formalized online-control algorithm leads to the “triumph” of the human factor or subjectivity. This is a major flaw in the digitalization era.

3 Possible Solution 3.1

The Essence of a Systematic Approach

We justify the use of the system approach. The notion of a “systematic approach” has been used more and more often in recent years, when they want to emphasize the complexity of the problem or the complexity of its solution. This is due to the increasing complexity and constant variability of the surrounding world. The analytical methods of solution that existed for a long time have proved inadequate. This fully applies to the management of production and social systems.

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The application of the system approach today is mainly used in the terminology, in the representation of the elements of the system and their connections, in the declaration of the notion of “dimensionality”, in mathematical models with simplified conditions for implementation. As a system approach we propose the “Method of statistical regularity for managing of the railway safety” (further – Method) ([7, 8] present the theoretical foundations and terminology of the Method). The basic concepts from the Method, which are used in the control algorithm: – statistics of traffic accidents/failures is the source of information about the shortcomings and deficiencies locations of transport processes; – the end result, as the aim and main system-forming factor of the transport system in accordance with the P.K. Anokhin’s theory of the functional system. This is one of the indicators of the managed system. In this approach, it is an indicator of the level of safety. Its dynamics serves as a criterion of similarity in the state of the transport system; – tolerance, as a violation of the law of transitivity. Tolerance is interpreted as ambiguity; – “bottleneck”, this is the most problematic place in providing safety, as well as a place of the maximum consumption of resources to maintain the stability of the system. Bottleneck is an analogue of the risk; – norm (functional optimum) is a stereotype (most probable) behavior of the transport system; – a statistical regularity (pattern) is a trend or a clear trend in the dynamics of statistical indicators that describe the activity of the railway system. 3.2

Online Control of Safety

The general idea of the online safety control is shown in Fig. 1.

Fig. 1. General scheme of online safety control.

We describe the functionality of the blocks shown in Fig. 1.

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Specification (Fig. 2) is a description of each transport event in the form of answers to eight questions that fully describe it: What, Where, When, Why, How accident happens, Who is guilty, To Whom subject bring damage, Motive (intentionally/ unintentionally). Answers on these questions can be obtained interactively with artificial intelligence.

Fig. 2. Specification of railway accidents.

A database of accidents is formed for each of the eight systematization questions. After each accident the database is updated. The deeper history of database, the more accurate the result. Statistics is presented: (a) as the dynamics of each parameter of systematization over time; (b) in the space of two or three parameters for example, (What – Where), (Who – Why), (What – Where – When),… This is a multi-vector analysis. The purpose of these presentations is the search of regularities (trends/tendency), which will help to identify bottlenecks. In terms of implementing the principles of INDUSTRY 4.0 [10–12], the accident database and multi-vector analysis perform the function of Big Data Analytics on the Fig. 1. The term “norm” is a key one in this system approach. The norm is understood as a statistical stereotype or functional optimum of system behavior (FOpt). The norm is formed by processing of violations statistics online. Therefore, it is said about the adaptation of the norm in real time. The principle of “bottleneck” is one of the main principles of the Method [7]. There are two demonstrations of the bottleneck: the “negative trend” and the “maximum ejection”. One of the output signals of Big Data Analytics [13] is the determination of the cause backgrounds (fundamental causes) that lead to transport events.

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This happens in two stages: 1. determine possible causes of violations of transportation rules from the three interaction groups “human – technology – environment”. These are technological reasons that arise in the process of train movement: unexpected failure of technical means of rolling stock/infrastructure, error of the driver or dispatcher, unforeseen environmental cataclysms; 2. determine backgrounds of possible causes that led to technological causes. They are not connected with the process of direct transportation and consist of four groups: equipment (its content and diagnostics), person (qualification, training, ability to perform work, working and rest conditions)), technology (organization of work in structural units, repair, current diagnostics, supply, management), environment (working conditions, interaction with other modes of transport, effects of third parties and nature). Reducing the influence of “bottlenecks” is the formation of management decisions that can reduce or exclude the influence of significant backgrounds. There are three types of management decisions at Ukrainian railways: operational, preventive, prospective. The specific content of this block is highly dependent on the transport company.

4 Conclusions 1. The proposed safety online-control allows not to provide safety in general, but to focus on “bottlenecks” in the activities of the transport company. This makes the management process transparent and directional, and financing efficient. 2. Conditions have been created for introducing digitalization into the process of security management in transport. This will reduce the influence of the human factor and improve the soundness of management decisions. 3. Use of the system approach will allow estimating integrally failures in the transportation process and moving from the concept of finding the guilty to the concept of identifying and eliminating bottlenecks into transportation process. 4. It is possible to apply the proposed control algorithm in other modes of transport, safety directions and technologies.

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3. Velychko, O., Gordiyenko, T.: Porivnyalnyj analiz rezultativ ocinyuvannya kompetentnosti texnichnyx ekspertiv metodamy analizu iyerarxij ta za modellyu Rasha. SxidnoYevropejskyj zhurnal peredovyx texnologij 3(93), 14–21 (2018) 4. Bochkovskii, A., Gogunskii, V.: Rozrobka metodu optymalnogo upravlinnya profesijnymy ryz`kamy. Sxidno-Yevropejskyj zhurnal peredovyx texnologij 3(93), 6–13 (2018) 5. The European Parliament: Directive 2004/49/EU (Railway Safety Directive). European Union: Off. J. Eur. Union (2004). https://eur-lex.europa.eu/legal-content/EN/TXT/?qid= 1541770402611&uri=CELEX:32004L0049 6. Ministry of Infrastructure of Ukraine: Regulations on the system of safety management of trains in the State Administration of Railway Transport of Ukraine. Official Bulletin of Ukraine, Kyiv (2011). http://zakon.rada.gov.ua/laws/show/z0729-11 7. Samsonkin, V., Druz, V.: Metod statystycheskoi zakonomernosty v upravlenyy bezopasnostiu dvyzhenyia na zheleznodorozhnom transporte [Method of statistical law in traffic safety management on rail transport]. DonYZhT, Donetsk (2005) 8. Samsonkin, V., Mojseyenko, V.: Theory of Rail Safety: Monograph. Karavela, Kyiv (2014) 9. Samsonkin, V., Druz, V., Feldman, A.: Applying of activities management based on selfleaning. EUREKA: Phys. Eng. 1, 29–38 (2018) 10. The Voice of European Railways: A Roadmap for Digital Railways. http://www.cer.be/ publications/latest-publications/roadmap-digital-railways 11. The Voice of European Railways: Joint Rail Sector Declaration on Digitalisation of Railways. http://www.cer.be/sites/default/files/publication/171109_Joint_Rail_Sector_ Declaration_on_Digitalisation_of_Railways.pdf 12. Pieriegud, J.: Digital Transformation of Railways. Printed by: Siemens Sp. z o.o., Poland. https://drive.google.com/drive/folders/1rLeoW03mMzs_nIJkGFoNG8hm-i7TKXgA 13. Samsonkin, V., Jurchak, O., Kuzmenko, D., Gaevskiy, V., Sorokin, M., Shcherbatenko, O., Lokhmatov, E., Savluk, V.: Roadmap of Digital Transformation of Ukrainian Railways. APPAU, Kyiv (2019)

Correction to: About Physical Aspects of Increasing Durability of Aluminum Alloys Due to Impact-Oscillatory Loading Mykola Chausov, Pavlo Maruschak, Elena Zasimchuk, Andrii Pypypenko, Roman Bishchak, and Iurii Burda

Correction to: Chapter “About Physical Aspects of Increasing Durability of Aluminum Alloys Due to Impact-Oscillatory Loading” in: K. Gopalakrishnan et al. (Eds.): TRANSBALTICA XI: Transportation Science and Technology, LNITI, https://doi.org/10.1007/978-3-030-38666-5_60

In the original version of the book, the following belated correction has been incorporated: The author name has been changed from “Mykola Chauso” to “Mykola Chausov” in the frontmatter and backmatter and in Chapter 60. The erratum chapter has been updated with the changes.

The updated version of this chapter can be found at https://doi.org/10.1007/978-3-030-38666-5_60 © Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, p. C1, 2020. https://doi.org/10.1007/978-3-030-38666-5_67

Author Index

A Aharkov, Oleksandr, 203 Ameen, Talal, 112 B Bakulich, Olena, 112 Baran, Denys, 40 Bartłomiejczyk, Mikołaj, 297 Basargan, Hakan, 273 Basu, Sujata, 76 Batarlienė, Nijolė, 57 Belyatynskyi, Andriy, 1 Bishchak, Roman, 572 Blatnický, Miroslav, 309, 320 Bobyr, Dmytro, 193 Bogdevičius, Marijonas, 290, 331, 350 Bogdevičius, Paulius, 350 Boichenko, Sergii, 601 Boyko, Aleksey, 386, 427 Budilovich (Budiloviča), Evelina, 552 Burda, Iurii, 572 Burdzik, Rafał, 47 Bureika, Gintautas, 235, 562 C Černiauskaitė, Laura, 521 Chausov, Mykola, 572 Čižiūnienė, Kristina, 122, 132 Costescu, Dan M., 415 D Danchuk, Viktor, 112 Das, Soumyadip, 99 Daukšys, Vygintas, 369, 407 Diahovchenko, Illia, 504

Dižo, Ján, 309, 320 Dmytrychenko, Mykola, 494 Donculaitė, Monika, 158 Drahiieva, Liudmyla, 203 Duchon, Frantisek, 263, 504 Durech, Peter, 466 Dvorak, Zdenek, 466, 474 F Fomin, Oleksij, 225, 581 Fomina, Yuliia, 225, 581 G Gabsalikhova, Larisa, 434 Gerlici, Juraj, 341, 581 Giniyatullin, Ilsur, 434 Gnatiuk, Liliia, 283 Gorbunov, Mykola, 220, 341 Gorbunov, Nikolai, 225, 235 Goretskyi, Oleksii, 633 Gromule, Vaira, 511 Gutarevych, Yurii, 494 H Hauser, Vladimir, 341 Holub, Halyna, 211 I Ilves, Risto, 185 Iurchenko, Valentina, 10 J Jarašūnienė, Aldona, 132 Jonika, Linas, 369, 407

© Springer Nature Switzerland AG 2020 K. Gopalakrishnan et al. (Eds.): TRANSBALTICA 2019, LNITI, pp. 639–641, 2020. https://doi.org/10.1007/978-3-030-38666-5

640 K Kalinowski, Dariusz, 245 Kalivoda, Jan, 531 Kamiński, Wojciech, 171 Kara, Serhii, 220 Karpenko, Mykola, 331 Khimeryk, Tetiana, 283 Klimenko, Irina, 531 Kliuiev, Serhii, 193 Konowrocki, Robert, 245 Kovtanets, Maksim, 235 Kravchenko, Kateryna, 341, 581 Krawiec, Krzysztof, 89 Krayushkina, Kateryna, 283 Kriaučiūnas, Donatas, 591 Kucera, Pavel, 361 Kukėnas, Vladas, 445 Kulbovskyi, Ivan, 211 Kurhan, Dmytro, 521 Kurhan, Mykola, 521 Kuszewski, Hubert, 601 Küüt, Arne, 185 Küüt, Keio, 185 L Lack, Tomas, 341, 581 Lagunovič, Vladislav, 132 Lebedeva, Elena, 10 Lebedevas, Sergėjus, 369, 407 Lejda, Kazimierz, 601 Lend, Enno, 139 Liachovičius, Edvardas, 455 Lovska, Alyona, 225, 581 Lunys, Olegas, 220 Luskova, Maria, 474 M Magdin, Kirill, 427 Makarova, Irina, 386, 427, 434 Maliavin, Anatoliy, 622 Maruschak, Pavlo, 40, 263, 504, 572 Maskeliūnaitė, Lijana, 610 Matijošius, Jonas, 484, 494 Matviienko, Oleksander, 622 Mavrin, Vadim, 427 Mazėtis, Erikas, 57 Meidutė-Kavaliauskienė, Ieva, 158 Melnikova, Oxana, 10 Mikhailov, Evgeny, 377 Mikhalevich, Nikolay, 10 Mogila, Valentin, 341 Mukhametdinov, Eduard, 434 Mukherjee, Deotima, 99 Musorina, Marina, 211

Author Index Mykhailova, Larysa, 10 Mykhailyshyn, Roman, 263, 504 N Neduzha, Larysa, 531 Novik, Hanna, 283 Nozhenko, Jelena, 151 Nozhenko, Volodymyr, 562 O Okulicz, Malwina, 18, 29 Oliynyk, Olena, 283 Olt, Jüri, 185 P Pashkevich, Anton, 386, 434 Petrenko, Viačeslav, 445 Połom, Marcin, 297 Porkuian, Olha, 151, 562 Prentkovskis, Olegas, 40, 350, 504 Prokop, Ales, 361 Prosvirova, Olga, 235 Pylypenko, Olexander, 1 Pypypenko, Andrii, 572 R Rehak, David, 474 Rehak, Kamil, 361 Rimkus, Alfredas, 484, 591 Roy, Sudip K., 99 Rutkowska, Paulina, 18, 29 S Saha, Pritam, 76, 99 Samsonkin, Valerii, 633 Sapronova, Svitlana, 203, 211, 377 Savkiv, Volodymyr, 263, 504 Segercrantz, Wladimir, 139 Semenov, Stanislav, 377 Sergienko, Oksana, 235 Shepel, Oleksandra, 484 Shevchenko, Anna, 622 Shuba, Yevhenii, 494 Shubenkova, Ksenia, 386, 427 Sivilevičius, Henrikas, 610 Skorupski, Jacek, 18, 29 Skrickij, Viktor, 455 Sładkowski, Aleksander, 171 Slivkova, Simona, 474 Słowiński, Paweł, 47 Smileski, Tasko, 397 Sorochak, Andriy, 40 Steišūnas, Stasys, 193, 309, 562 Stepanchuk, Oleksandr, 1

Author Index Stravinskas, Saulius, 484, 591 Svatko, Vitaliy, 112 Syrota, Oleksandr, 494 Szolc, Tomasz, 245 T Tkachenko, Viktor, 203, 211, 377 Torok, Adam, 67 Török, Árpád, 273 Trifonov, Dmitrij, 494 Trofimov, Igor, 601 Turla, Vytautas, 622 Tverdomed, Volodymyr, 203 U Ugnenko, Evgeniya, 622 V Vaičiūnas, Gediminas, 151, 193, 220, 235, 320 Vasiliauskas, Aidas Vasilis, 158

641 Vasilienė-Vasiliauskienė, Virgilija, 158 Vipartas, Tadas, 484 Viselga, Gintas, 622 Vitkūnas, Rolandas, 122 Vrtanoski, Gligorche, 397 Y Yakovlieva, Anna, 601 Yatskiv (Jackiva), Irina, 511, 552

Z Zasimchuk, Elena, 572 Zefreh, Mohammad Maghrour, 67 Zervina, Olga, 541 Zöldy, Máté, 255 Zsolt, Szalay, 273 Zsombók, Imre, 255 Žygienė, Rasa, 290