Communications - Scientific Letters of the University of Zilina, 2020 (vol. 22), issue 3
Operation and Economics in Transport
Influence of the Ionospheric Delay on Designation of an Aircraft Position
Janusz Cwiklak, Marek Grzegorzewski, Kamil Krasuski
Communications - Scientific Letters of the University of Zilina 2020, 22(3):3-10 | DOI: 10.26552/com.C.2020.3.3-10 
The article presents and describes research results concerning determination of an impact of the ionospheric correction upon the positioning accuracy of an aircraft. The main objective of examinations was to verify three ionospheric models (the Klobuchar model, SBAS model and IONEX model) in determining aircraft coordinates. In the framework of the conducted simulations, the authors determined the aircraft coordinates by means of the SPP code method in the GPS system. The article presents a comparison of the determined aircraft coordinates in the SPP code method in relation to an accurate solution in the RTK-OTF differential technique. Based on the...
Determination of the Precise Coordinates of the GPS Reference Station in of a GBAS System in the Air Transport
Kamil Krasuski, Stepan Savchuk
Communications - Scientific Letters of the University of Zilina 2020, 22(3):11-18 | DOI: 10.26552/com.C.2020.3.11-18
This paper presents results of research concerning determination of the GPS reference station coordinates located on the grounds of an EPDE airport in Deblin. The study uses a mathematical model of the PPP measurement technique in order to determine the coordinates of the reference station using the real GPS code-phase observations. The computations of the coordinates of the GPS reference station were carried out in numerical applications CSRS-PPP, APPS and GAPS. In this research was found that the accuracy of finding solutions to the XYZ geocentric coordinates of the reference station REF1 between solutions CSRS-PPP, APPS and GAPS ranges from 0.01m...
Assessment of the Pallet Unit Load Stability by Simulation Methods
Tomasz Matyja
Communications - Scientific Letters of the University of Zilina 2020, 22(3):19-28 | DOI: 10.26552/com.C.2020.3.19-28
The paper presents a simulation model of a loading unit dynamics, with a layered structure, wrapped with a stretch film. Stretch film wrapping is the most commonly used and cheap method of securing the load unit. The model, proposed by the author, allows assessing the stability of the unit during the transport operations, when the loading unit is subjected to inertial forces. Deformations of a unit and prediction of its disintegration in extreme cases can be evaluated based on results of a simulation. The value of the necessary containment force as well as the number of wraps with the pre-stretched film, can also be estimated. In effect, simulations...
Application of System-Dynamic Modeling to Improve Distribution Logistics Processes in the Supply Chain
Galimkair Mutanov, Sayabek Ziyadin, Askhat Serikbekuly
Communications - Scientific Letters of the University of Zilina 2020, 22(3):29-39 | DOI: 10.26552/com.C.2020.3.29-39
This article presents an approach of improve logistics processes with the system dynamics modeling of two different processes scenarios. System dynamics is used, not only as a causal loop diagram, but calculated measures of end-user satisfaction indicators were provided by experts, as well. Literature review of fundamental definitions and recent ideas in subject of supply chain management (SCM), system dynamics (SD), business processes model and notation (BPMN) and distribution logistics for dozens of major sources, has been made. In the work, methods of expert interviews, content analysis of recent publications, system-dynamic modeling...
Safety Implications of GNSS Signal Interference at Zilina Airport
Andrej Novak, Alena Novak Sedlackova, Anna Stelmach, Doris Novak
Communications - Scientific Letters of the University of Zilina 2020, 22(3):40-48 | DOI: 10.26552/com.C.2020.3.40-48
The paper deals with the issue of GNSS interference and its subsequent impact on airport approach procedures. It discusses the problem of GNSS signal interference and interference identification on a practical example of a small regional airport in Zilina, located close to the highway, through research aimed at its identification, a proposal for the location of a monitoring station and subsequent practical verification. The paper seeks to analyse and provide recommendations for enhancing safety and reliability in GNSS approaches. Given the need to develop the air transport, it is important to ensure the safety and continuity of service provision at...
Decomposing the Influencing Factors of Energy Intensity in the Passenger Transportation Sector in Indonesia
Dhani Setyawan
Communications - Scientific Letters of the University of Zilina 2020, 22(3):49-58 | DOI: 10.26552/com.C.2020.3.49-58
Indonesia's transport sector has experienced rapid growth that has caused excessive fossil fuel energy consumption. Over 2000 to 2016 total final energy consumption in Indonesia's transport sector has grown by 10% per annum so that transport now provides a large and rapidly growing component of total energy use. This study analyzes the specific characteristics of energy intensity in the transportation sector in Indonesia from 2000 to 2016 by employing a multiplicative Log Mean Divisia Index-II. The passenger transport sector in Indonesia, including the four modes of road, rail, water and air is examined in this study. Overall, the decline in energy...
Implementation System of Technical Specification for Interoperability for the Rolling Stocks
Jaromir Siroky, Katarina Magdechova, Petr Nachtigall, Stephan Schroder, Pavlina Siroka
Communications - Scientific Letters of the University of Zilina 2020, 22(3):59-67 | DOI: 10.26552/com.C.2020.3.59-67
In the paper, the present state of scientific knowledge in authorising the types of railway vehicles in Slovakia and abroad is analysed by the authors. The aim of the authorisation of the types of railway vehicles is to take into account the interests of the whole society in the field of transport in the manufacturing of these vehicles or their import from abroad. These interests mainly include a greater security of transport, as well as a greater quality, reliability and lifespan of railway vehicles. The authors also analyse the Commission Recommendation 2014/897/EU of 5 December 2014 on matters related to the placing in service and use of structural...
Life Cycle Cost (LCC) Level of an Urban Transport Fleet with Differentiated Share of Buses with Alternative Drive Systems
Emilia M. Szumska, Rafal S. Jurecki, Marek Pawelczyk
Communications - Scientific Letters of the University of Zilina 2020, 22(3):68-77 | DOI: 10.26552/com.C.2020.3.68-77
In recent years, there has been a significant increase in the number of buses operated by urban public transport companies powered by alternative fuels and equipped with alternative drive systems. In addition to economic factors, operators should also take environmental aspects into account when purchasing new vehicles. In this case, a useful criterion for selecting a vehicle is the Life Cycle Cost (LCC), which, in addition to the cost of purchasing a bus, takes into account the necessary expenses associated with its maintenance, operation, decommissioning, as well as emissions costs. This paper presents a study of the LCC values, estimated for the...
Mechanical Engineering in Transport
Analysis of Dynamic Parameters of the System of Raster Formation and Control
Antanas Fursenko, Arturas Kilikevicius, Kristina Kilikeviciene, Jonas Skeivalas, Albinas Kasparaitis, Jonas Matijosius, Dariusz Wieckowski
Communications - Scientific Letters of the University of Zilina 2020, 22(3):78-88 | DOI: 10.26552/com.C.2020.3.78-88
The presented research work analyzes the sensing system, the main aim of which is a raster formation and controlling this process using the optical measuring equipment and high precision angle encoders. Optical measuring equipment are used for the raster position detection, meanwhile angle encoders for controlling the tape speed. The main parameter of raster formation process is fixed transportation speed, but there are difficulties to realize it, because there is imperfection of the device elements. The article analyzes the dispersion of vibration accelerations of the raster formation device and tape in the two directions (transverse and longitudinal)...
Improvement of Traction Indicators of a Track-Chain Tractor
Salavat Mudarisov, Ilshat Gainullin, Ildar Gabitov, Eduard Khasanov
Communications - Scientific Letters of the University of Zilina 2020, 22(3):89-102 | DOI: 10.26552/com.C.2020.3.89-102
The aim of this research was to conduct the comparative traction tests for T-170M1.03-55 tractor with a flat and elliptical rim. Structurally rational geometry of the crawler's support surface for tractors with semi-rigid suspension is realized by placing the support rollers at different heights relative to the cart. The results of traction tests showed that elliptical track rim has increased the maximum traction power by 10.4%, conditional traction propulsive efficiency coefficient to 7.43% and the specific traction effort by 8%. The increase in indicators is provided by a lower rolling resistance of a tractor with an elliptical rim. Reduction of...
Electrical Engineering in Transport
Research of a Hybrid Diesel Locomotive Power Plant Based on a Free-Piston Engine
Serhiy Buriakovskyi, Borys Liubarskyi, Artem Maslii, Danylo Pomazan, Tatyana Tavrina
Communications - Scientific Letters of the University of Zilina 2020, 22(3):103-109 | DOI: 10.26552/com.C.2020.3.103-109
This article describes one of the possible ways for improving the energy efficiency of shunting diesel locomotives. It means a replacing a traditional traction electric transmission with a diesel generator set with a hybrid transmission with a free-piston internal combustion engine and a linear generator. The absence of a crankshaft in an internal combustion engine makes it possible to reduce thermal and mechanical losses, which, in turn, leads to an increase in the efficiency of traction electric transmission of the diesel locomotive.
Equivalent Electrical Model of an Inductor Excited by a Triangular Current Including Saturation
Jorge Rafael Gonzalez-Teodoro, Enrique Romero-Cadaval, Rafael Asensi, Vladimir Kindl
Communications - Scientific Letters of the University of Zilina 2020, 22(3):110-118 | DOI: 10.26552/com.C.2020.3.110-118
A model for an equivalent electrical circuit designed for a ferrite (3C90) inductor usually used in power converters excited by a non-sinusoidal current appropriate for use in power electronics is proposed. This study, based on 3D finite element analysis, leads to significant precision advantages over 2D analysis for non-symmetric inductors. The frequency range of the analysis for the toroidal core was between 15 kHz and 1 GHz, with different levels of excitation in non-saturation and saturation status focusing on the power loss.
Fiber Optic Phase-Based Sensor for Detection of Axles and Wheels of Tram Vehicles
Jan Nedoma, Michal Kostelansky, Michael Fridrich, Jaroslav Frnda, Miroslav Pinka, Radek Martinek, Martin Novak, Stanislav Zabka
Communications - Scientific Letters of the University of Zilina 2020, 22(3):119-127 | DOI: 10.26552/com.C.2020.3.119-127
This paper presents a novelty approach to usage of the fiber-optic phase-based sensor in railway transportation. We designed and tested the real deployment of this sensor working on the principle of light interferences within optical fibers. The proposed construction of the sensor allowed to increase the sensitivity and thanks to this can be detected and calculated individual axles and wheels of tram vehicles. We performed long-time period measurements (April to September 2019) in diverse climatic conditions, including measurements of 642 tram passages (several different construction types) in real urban traffic. The detection accuracy level was slightly...
Management Science and Informatics in Transport
Improving TSP Solutions Using GA with a New Hybrid Mutation Based on Knowledge and Randomness
Esra'a Alkafaween, Ahmad B. A. Hassanat
Communications - Scientific Letters of the University of Zilina 2020, 22(3):128-139 | DOI: 10.26552/com.C.2020.3.128-139
Genetic algorithm (GA) is an efficient tool for solving optimization problems by evolving solutions, as it mimics the Darwinian theory of natural evolution. The mutation operator is one of the key success factors in GA, as it is considered the exploration operator of GA. Various mutation operators exist to solve hard combinatorial problems such as the TSP. In this paper, we propose a hybrid mutation operator called "IRGIBNNM", this mutation is a combination of two existing mutations; a knowledgebased mutation, and a random-based mutation. We also improve the existing "select best mutation" strategy using the proposed mutation. We conducted...
Safety and Security Engineering in Transport
Alarm Systems in Buildings - Investigation of Effectiveness Depending on Building Type and User Profile
Gero Gerber
Communications - Scientific Letters of the University of Zilina 2020, 22(3):140-147 | DOI: 10.26552/com.C.2020.3.140-147
Alarm systems are used to warn passengers and employees in railway stations, airports, logistics facilities and administrative buildings of hazards; in this way, they are instructed to rescue themselves. A large online survey conducted in Germany in 2018 has shown that often sounding the alarm does not have the desired effect. The research presented in this article investigates dependence of an alarm effectiveness on type of building, user profile and type of the alarm system. In this paper, general and building-specific measures, using which the effective sounding of the alarm and optimal behaviour of the building users in the case of danger...