Science and Transport Progress

27-35

Authors: V. I. Shcheka

Purpose. Еlectromagnetic processes in «contact network-rails-earth»system should be researched for the purpose of electromagnetic compatibility rail circuits with traction power supply system providing and improving traffic safety on railway transport. Methodology. The methods of scientific analysis, mathematical modeling, experimental investigation, scale modeling have been applied to achieve this goal. Findings. Conducted theoretical and experimental investigations, indicate that electromagnetic processes in the «contact network-rails-earth» system in nearest zone in frequency range up to 1 MHz and it give us an opportunity to consider, that electromagnetic field of hindrance consists of two components: electric and magnetic. Each of them has its own mechanism to influence the rail circuits. In consequence of research the theoretical and experimental dependences of electromotive force induced in wire-receiver from the hindrance current frequency have been received. The frequency graph of relative error according to data «theory-experiment» has been received. The adequacy by Wilcoxon criterion of mathematical model to experimental data has been proved. Originality. The results of theoretical and experimental investigations of magnetic influence between two contours gives us a concurrence in frequency range up to 1000 Hz with average relative error 2, 33 %. With hindrance current frequency one can observe certain increasing the average relative error between calculated and measured values of electromotive force induced in the wire-receiver. Practical value. The adequacy by Wilcoxon criterion of mathematical model to experimental data has been proved on significance level 5 %. It gives an opportunity to use this mathematical apparatus for the investigation of electromagnetic processes in lines with plenty of wires and in «contact network-rails-earth»system in range up to 1000 Hz. The obtained results can be useful in designing, researching and providing electromagnetic compatibility of rail circuits with traction power supply system.

45-57

Authors: D. M. Kozachenko, A. I. Verlan, O. V. Horbova

Purpose.This article aims to improve the evaluation of irregularity of freight transport and calculated volumes determination of work for railway stations and sidings of industrial enterprises. Methodology. The methods of mathematical statistics are used as research methods for estimation of calculated volumes of traffic and loaded traffic, in particular, the methods of time series analysis; the methods of mathematical modeling are used to evaluate the calculated volumes of empty traffic. Findings. Calculated volumes of the main-line and industrial railway stations activity are determined according to the monthly and daily irregularity. Monthly irregularity is proposed to evaluate against the trend of the indicator over the last 3-5 years, constructed using the method of weighted moving average. The 30-day period in the previous year with the largest total amount of work is proposed to use as the calculation period for the assessment of daily irregularity. The computation size of empty traffic volumes is proposed to be determined on the basis of loaded traffic volumes with the probability matrix of cars usage for dual operations. The proposed method is verified by the work volume calculation for the year 2014 according to previous time periods. The test results showed that the proposed method as compared with traditional one provides higher stability of the results when changing time periods, used for analysis, as well as a more accurate assessment of the calculated volumes of work. Originality. Authors have improved determination methods for the calculated volumes of work to railway stations through the using time series analysis methods. Practical value. The proposed methodology allows assessing more accurately the prospective volumes of work and, through this, reduce the amount of capital expenditures associated with the development of stations and operating costs associated with their operation. The method can be used to improve the governing and methodological documents regulating the design and development of technological processes of the main-line and industrial railway stations.

77-87

Authors: O. O. Matusevych

Purpose. The study provides the methods and models development of reducing damages of traction energy systems (TES) at electrified railways of Ukraine. Definition the indicator of preventing damage evaluation TES at electrified railways is necessary. Paper is aimed to search the modern methods and approaches to improve the system of TES monitoring, diagnosis and maintenance. Methodology. To achieve this purpose a study of foreign experience and publications that focus on problem-solving quality of TES using a linguistic approach based on the theory of fuzzy multiple numbers and linguistic variable were done. Findings. In result of research an algorithm to reduce TPS damages which operates under uncertainty was developed. It is found that the solution of this problem is possible by timely detection of actual technical condition of equipment in terms of quality maintenance, diagnostics and update resource of electrical equipment traction substations (TS) power supply TES. The study examined the fuzzy inference scheme, which is based on the use of mechanisms to minimize the area of decision-making. It contributes not only to structural identification in the process of developing a database, but also can significantly improve the efficiency of finding the parameters of fuzzy model, which in turn reduces the efforts that are necessary for the analysis and the design of effective control systems maintenance and repair (M and R) TES. Originality. For the first time the algorithm of reduction the damage of traction energy system of electrified railways of Ukraine was offered. The mathematical model of reduction the damage calculation of TES from TP power equipment failures by improving system maintenance (M and P) was developed. Firstly evaluation index was proposed to prevent the damage of traction energy system. Practical value. The article describes the fuzzy inference scheme, which is based on the use of the mechanism to minimize the area of decision-making and contributes not only to structural identification in the process of developing a database, but also can significantly improve the performance of determining the parameters of fuzzy model. Implementation of this approach comes to the determination of the main stages, features and optimal justification of quantitative and qualitative requirements for system M and R of TS. It will be done with allowable costs for improvements to reduce TPS damage and address the equipment of traction substations in working condition in terms of growth rates and volumes aging (compared to the current speed and volume of updates).

97-106

Authors: K. O. Soroka, D. A. Lychov

Purpose. The calculation methods improvement of the electric vehicle curve movement and the cost of electricity with the aim of performance and accuracy of calculations improving are considered in the paper. Methodology. The method is based upon the general principles of mathematical simulation, when a conceptual model of problem domain is created and then a mathematic model is formulated according to the conceptual model. Development of an improved conceptual model of electric vehicles motion is proposed and a corresponding mathematical model is studied. Findings. The authors proposed model in which the vehicle considers as a system of interacting point-like particles with defined interactions under the influence of external forces. As a mathematical model the Euler-Lagrange equation of the second kind is used. Conservative and dissipative forces affecting the system dynamics are considered. Equations for calculating motion of electric vehicles with taking into account the energy consumption are proposed. Originality. In the paper the conceptual model of motion for electric vehicles with distributed masses has been developed as a system of interacting point-like particles. In the easiest case the system has only one degree of freedom. The mathematical model is based on Lagrange equations. The shown approach allows a detailed and physically based description of the electric vehicles dynamics. The derived motion equations for public electric transport are substantially more precise than the equations recommended in textbooks and the reference documentation. The motion equations and energy consumption calculations for transportation of one passenger with a trolleybus are developed. It is shown that the energy consumption depends on the data of vehicle and can increase when the manload is above the certain level. Practical value. The authors received the equations of motion and labour costs in the calculations focused on the use of computer methods of numerical integration. The calculation expenses are reduced. The accuracy is improved; provided possibility to consider different parameters influencing the motion. A certain environmental effect can be achieved by orientation calculation methods for the practical development of the process charts of the movement of electric vehicle funds in different operating conditions at a constant change of filling the interior of the vehicle.

118-128

Authors: D. M. Kurhan

Purpose. On the basis of theoretical assumptions and experimental studies the paper provides the choice of the factors for the formation of dynamic load on the track of modern rolling stock in the conditions of high-speed. This results in a calculation method of determining a vertical force which acts on the wheels on the rails. Methodology. The current trend of development of transport networks is the introduction to Ukrainian railways speed, and in the future – high-speed, passenger trains. Fundamental structural changes in these trains, and a significant increase in speed results in a need to revise the calculation methods of action of rolling stock on the railway track, the ratio of the standard deviations of various dynamic forces, assess the impact of different factors for different speeds. In the work investigated the change in the dynamic load on the results of experimental measurements. Findings. The dependences of the average and the calculated forces on the speed of modern passenger trains were obtained. Using factor analysis of variance obtained numerical characteristics of the influence of different factors on the value of the vertical force acts on the wheel rail and the degrees of influence of various factors on its deformation were determined. Based on the results of experimental and theoretical research, the necessity of revising the methodology for determining the estimated power for practical calculations the way to strength in terms of passenger trains at high speeds was grounded. Originality. On the basis of theoretical research and analysis of statistical data of experimental measurements it was found that the main factor driving the dynamic vertical force component for modern passenger trains are the vibrations of the «wheel-rail» system or so-called «dynamic wheel passing the rough ways». Practical value. Existing methods of calculating the dynamic component of the vertical forces need such indicators as the reduced mass of the way. The obtained results in the study indicate that a parameter is artificial and can only be used for low speeds at the level of static calculation schemes.

137-144

Authors: I. A. Vakulenko, Yu. L. Nadezhdin, V. A. Sokyrko, Xu Xiao Hai

Purpose. It is determining the nature of the ferrite grain size influence of low-carbon alloy steel on the speed propagation of acoustic vibrations. Methodology. The material for the research served a steel sheet of thickness 1.4 mm. Steel type H18T1 had a content of chemical elements within grade composition: 0, 12 % C, 17, 5 % Cr, 1 % Mn, 1, 1 % Ni, 0, 85 % Si, 0, 9 % Ti. The specified steel belongs to the semiferritic class of the accepted classification. The structural state of the metal for the study was obtained by cold plastic deformation by rolling at a reduction in the size range of 20-30 % and subsequent recrystallization annealing at 740 – 750 ° C. Different degrees of cold plastic deformation was obtained by pre-selection of the initial strip thickness so that after a desired amount of rolling reduction receives the same final thickness. The microstructure was observed under a light microscope, the ferrite grain size was determined using a quantitative metallographic technique. The using of X-ray structural analysis techniques allowed determining the level of second-order distortion of the crystal latitude of the ferrite. The speed propagation of acoustic vibrations was measured using a special device such as an ISP-12 with a working frequency of pulses 1.024 kHz. As the characteristic of strength used the hardness was evaluated by the Brinell’s method. Findings. With increasing of ferrite grain size the hardness of the steel is reduced. In the case of constant structural state of metal, reducing the size of the ferrite grains is accompanied by a natural increasing of the phase distortion. The dependence of the speed propagation of acoustic vibrations up and down the rolling direction of the ferrite grain size remained unchanged and reports directly proportional correlation. Originality. On the basis of studies to determine the direct impact of the proportional nature of the ferrite grain size on the rate of propagation of sound vibrations in the low-carbon alloy steel. The directly proportional nature of influence of ferrite grain size on the speed propagation of acoustic vibrations in low-carbon alloy steel on the basis of the conducted researches is defined. The paper is shown that at increasing in the size of the recrystallized ferrite grain the degree of influence the texture from the previous cold plastic deformation by rolling increases. Practical value. The received results on nature determination of influence of ferrite grain size on the speed propagation of acoustic vibrations can be the useful by development of techniques of non-destructive testing of metal materials quality. The special value the specified technique of measurement acquires in the conditions of line production of metal constructions.

162-175

Authors: V. M. Bohomaz

Purpose. A drive behaves to the basic elements of scoop band elevators. To determine the drive power calculations are carried out according to standard methods, which take plenty of time. It is necessary to conduct the analysis of influence of project characteristics on the parameters of high-speed drive in a scoop bent elevator and to build the improved algorithm of speed-up determination of its drive power on project descriptions, that will take into account the type of load, rise height, necessary productivity, standard parameters of scoops and tape. Methodology. Using parametric dependences of elevators drive power on its project characteristics, received by the author earlier, the improved algorithm of speed-up determination of elevators high-speed drive power with deep and shallow scoops at set type of load, productivity, rise height was offered. Findings. The algorithm of drive power speed-up determination of high-speed vertical elevators with deep and shallow scoops depending on project parameters was offered. The example of such algorithm application is considered for an elevator that is intended for transporting of cement. Analytical dependences of drive power of such elevator are determined on the productivity and rise height. Corresponding graphic dependences were built and character of drive power changes during the size changing of any project characteristics was determined. Originality. The improved algorithm of drive power elevator determination at the given project characteristics (type of load, rise height, productivity) that takes into account standard sizes, parameters of scoops and ribbons, was built at first time. Practical value. The use of an offered algorithm of calculation gives the possibility of relatively fast determination of reference value of high-speed elevators drive power with deep and shallow scoops, to build graphic dependences of drive power on the values of the productivity and rise height at the certain type of load, that assists the quality selection of his basic elements at certain project descriptions, such algorithm gives an opportunity to save time on calculations in the process of elevators planning.

186-198

Authors: S. V. Myamlin, N. Yu. Naumenko, O. M. Markova, H. M. Kovtun, V. V. Maliy

Purpose. The paper is devoted to dynamic characteristics evaluation of the locomotive with prospective design and determination the feasibility of its use on the Ukrainian railways. Methodology. The methods of mathematical and computer modeling of the dynamics of railway vehicles, as well as methods for the numerical integration of systems of ordinary nonlinear differential equations were used to solve the problem. Findings. The calculated diagram of a locomotive on three-axle bogies was built to solve the problem, and it is a system of rigid bodies connected by various elements of rheology. The mathematical model of the locomotive movement, allowing studying its spatial vibrations at driving on straight and curved sections of the track with random irregularities in plan and profile was developed with use of this calculated diagram. At compiling the mathematical model took into account both geometric (nonlinearity profile of the wheel roll surface) and physical nonlinearity of the system (the work forces of dry friction, nonlinearity characteristics of interaction forces between wheels and rails). The multivariate calculations, which allowed assessing the dynamic qualities of the locomotive at its movement along straight and curved sections of the track, were realized with the use of computer modeling. The smoothness movement indicators of the locomotive in horizontal and vertical planes, frame strength, coefficients of vertical dynamics in the first and second stages of the suspension, the load factor of resistance against the derailment of the wheel from the rail were determined at the period of research. In addition, a comparison of the obtained results with similar characteristics is widely used on the Ukrainian railways in six-axle locomotive TE 116. The influence of speed and technical state of the track on the locomotive traffic safety was determined.Originality. A mathematical model of the spatial movement of a six-axle locomotive with prospective design, taking into account the peculiarities of its design was developed. Evaluation of dynamic characteristics at the carriage movement along a track of arbitrary shape was made. Practical value. The developed mathematical model of the six-axle locomotive movement can be used at conducting research on development of advanced locomotives designs.

208-214

Authors: K. M. Pererva

Purpose. This paper is a study of innovative methods of learning and teaching English with the help of Internet resources and students motivation to seek the necessary information at homework. Methodology. The main principle of the Web-Quest as a type of English language teaching is to motivate students. For example, by participation in the Web-Quest students, who were unsure of their knowledge, become more confident. Having clear goals and objectives, using computer skills, motivated young people more actively acts as a confident user of English. Findings. According to the technology of We-Quests students were asked to create one or more projects directly related to the successful execution of the work. It is a significant result of all the hard work of students, and it is the subject of evaluation. Evaluation is an essential component of Web-Quest or any other project, and from this point of view, the criteria should be clear and accessible to students from the very beginning. These instructions can and should be changed in order to differentiate and provide an oral presentation and written work. Originality. Basically, Web-Quests are mini-projects in which a higher percentage of the material obtained from the Internet. They can be created by teachers or students, depending on the type of training work. The author detailed the increase of possibilities in the search of Internet projects with other creative types of student work. They may include: review of the literature, essay writing, discussion of read works and other. Practical value. The paper confirmed that the roles and tasks, reflecting the real world, invites to cooperate, stimulate and train the thinking process at a higher level. That is why the use of Web-Quests can improve the language skills of the educational process (reading for information extraction, detailed reading, negotiations, oral and written communication, and other).