2017

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Forecasting of Passenger Traffic upon Implementation of High-Speed Running
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2017) Kurhan, Mykola ; Kurhan, Dmytro
ENG: Purpose. Forecasting of passenger traffic flows in the future is an essential and integral part of the complex process of designing of high-speed network (HSN). HSN direction and its parameters are determined by the volume of passenger traffic, the estimated value of which depends on the economic performance of the country, as well as the material status of citizens living in HSN concentration area, transport mobility of population, development of competing modes of transport and so on. The purpose of this work is to analyse the existing methods of passenger traffic forecasting, to evaluate errors of the existing models concerning determination of traffic volumes and to specify the scientific approach to the development of high-speed rail transport in Ukraine. Methodology. The existing forecasting methods are reduced to the following ones: Delphi approach, extrapolation method, factor and correlation analysis, simulation method. The method described in this paper is based on scientific approaches such as analysis – a comprehensive and detailed study of various aspects of the known forecasting methods, comparing of existing methods for establishing differences and similarities, as well as deduction – use of general knowledge to get the new particular one. Thus, the unified indicators determined for the country as a whole, such as gross domestic product, national income, total population and others cannot be used to forecast the traffic flow on specific areas of HSN construction. Therefore, it is necessary to move from the overall forecast to traffic volume forecast on particular direction. Findings. The conclusions are derived from the analysis of different approaches and methods of passenger flow forecasting. It is proposed to create typical techniques of traffic flow forecasting using modern mathematical methods that would allow avoiding unreasonable decisions and shortening project development time. The resulting recommendations will help in the efficiency of design decisions, as well as will determine the quality of the project in whole and the feasibility of its implementation in particular. Originality. The scientific approaches to forecasting the passenger traffic volume in HSN agglomeration area were further developed. The HSN feasibility study criteria system was updated; this system takes into account passenger transit flows through Ukraine, the population of the cities covered by the high-speed network, mobility of population and other factors. Practical value. The data obtained by authors can be used to justify the concept of highspeed rail transport development in Ukraine, to create a high-speed network and to phase HSN construction.
Railway Track Representation in Mathematical Model of Vehicles Movement
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2017) Kurhan, Mykola ; Kurhan, Dmytro
ENG: Purpose. The tasks of modeling the interaction of track and rolling stock are basic ones for most areas of modern scientific research of railway transport. The compilation of the model by the principle of Lagrange d'Alembert has found a very wide application for solving the problems of rolling stock dynamics. Representation of the railway track in the model of vehicle movement can be implemented in several ways, which, among other things, will differ in detail. The purpose of this work is to create a methodology for representing the railway track in mathematical models of interaction with rolling stock and obtaining practical results for different characteristics and design of the track and the level of maximum speed. Methodology. The problem consists of determining such track characteristics as the reduced mass, the stiffness coefficient, and the dissipation coefficient. As a tool for solving this problem we used the model of the stress-strain behavior of the railway track based on the joint use of the elastic wave propagation equations to describe the topography of the part of the system that is involved in the interaction at a given time and the equations of dynamic equilibrium of its deformation. This makes it possible to take into account the dynamics of the deflection of the underrail base, which is especially important for the conditions of passenger traffic, which can be carried out at high speed. Findings. The authors obtained theoretically justified stiffness and dissipation coefficients of the railway track for calculating the dynamics of rolling stock in modern models based on systems of equations in accordance with the Lagrange d'Alembert principle. The established values, in contrast to those given in other sources, have a reasonable dependence on the track design and the speed of movement. Originality. The authors expanded the approaches of railroad track representation in models of rolling stock described by systems of equations by the Lagrange-d'Alembert principle. The paper presents the developed method for determining the characteristics of the railway track for such models is based on the results of variant calculations of the dynamic deflection of the rail from the passage of the wheel. Practical value. The authors obtained the values of the stiffness and dissipation coefficients of the railway track depending on the design and speed of motion for practical use in appropriate models of interaction between track and rolling stock.