Search results
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V.3(31), 2017
95-102In article temporary characteristics and results of the analysis of operation of the relay - the differential shunt are considered at full removal of a package of steel on a branch of smaller section. Conclusions are drawn on opportunities of its application at pass by the electrorolling stock of the isolating interfaces. The method of the choice of settings of the relay - the differential shunt, considering time delay at its operation is offered. -
V.4(48), 2021
96-108The article presents an analysis of the failures of the mechanical components of the mainline electric locomotives 2ES6 «Sinara» in operation at the landfill of the West Siberian Railway, the causes and consequences of failures of the most vulnerable nodes are determined. The analysis of failures of the mechanical components showed that a significant share of them falls on the components of the wheel-motor unit of the locomotive. The analysis of the design features of the crew part is carried out. The main structural difference of suspension is the absence of leaf springs in the axle box stage, which were widely used on electric locomotives of previous generations. In the body stage, helical springs (Flexicoil) are used instead of the cradle suspension. The connection of the traction motor with the trolley frame is a pendulum. The suspension of the traction motor to the trolley frame is carried out through a leash. When considering the vibrations of railway carriages, it is customary to represent the locomotive and the track as a single mechanical system. The task of forming a mathematical model of the «electric locomotive - path» system is set and a mathematical model of vertical vibrations of an electric locomotive is formed taking into account the dynamics of wheel-motor blocks based on the Lagrange equation of the second kind in the form of a matrix equation, which allows us to assess the loading of mechanical components in operation. The mathematical model represents a system of differential equations in which six equations determine the fluctuations of the bouncing and galloping of the body and trolleys, four - the galloping of wheel-motor blocks, four - the bouncing of wheel pairs together with the reduced mass of the track. The obtained mathematical model makes it possible to determine the level of dynamic loading of the components of the mechanical part of the electric locomotive 2ES6 «Sinara» by integrating the matrix equation using the MathCAD application package. -
V.3(15), 2013
96-103In this paper we propose an electric load forecasting algorithms based on artificial neural networks. An improved method for selecting the most appropriate structure of the neural network based on the coefficient characterizing the homogeneity of the samples is proposed. -
V.1(25), 2016
96-104The authors propose a model of justification of the duration of the operation liner-tamping-straightening and construction machinery. Using this model, we can evaluate the efficiency and reliability of machines on any object. This allows you to most reliably predict the timing of production of certain types of works and their cost at the design stage. The article presents the indicators of full-scale tests and the estimation of reliability of manufacturing operations. One of the main factors of reliability of work of construction machines is the utilization of their time. All normative documents are obsolete data on the utilization of machines during the working time, which need updating, as the machines are constantly improving. To assess the reliability of working machines, the authors developed a database of the results of field tests liner-tamping-straightening machines, cranes, excavators, bulldozers, pipe layers, drilling rigs and dredges. To prove the validity of database values according to the results of full-scale tests were carried out two stages of verification: logical and mathematical. After sampling in accordance with GOST R 8.736-2011 was verified that it belongs to the law of normal distribution using the criterion of Pearson agreement. It was further calculated the reliability and risk of the planned volume of work in scheduled period of time. When it was considered the utilization ratio of machines time and the risk of deviation from the mean. The proposed approach to the assessment of duration of liner-tamping-straightening and construction machinery can be extended to any type of equipment and will allow to obtain numerical values for evaluating the reliability of production work in the scheduled time, which is very important in the construction, repair and maintenance. -
V.1(61), 2025
96-107The article considers methods for optimizing traffic flow management in large agglomerations by using clustering, routing and principles of queuing theory. The main study is devoted to the redistribution of resources by introducing a priority system in request processing. The influence of urgency, density and throughput of cargo flow on the system operation is analyzed and optimization algorithms are proposed to reduce waiting time, reduce costs and improve the efficiency of transport processes. The research methodology includes the use of a multi-channel queuing model to assess the impact of priority distribution of requests on the system throughput. Mathematical modeling, linear programming methods and NPV calculation for assessing economic efficiency are used to analyze the redistribution of resources. The results of the study show that the priority service system reduces the waiting time for urgent requests, but under high load it can increase the waiting time for less priority clients. The developed resource redistribution algorithm adapts the system to changes in flow intensity. The use of the proposed methods made it possible to reduce the average waiting time for priority requests by 1.5-2 times and reduce operating costs. The practical significance of the study lies in increasing the efficiency of transport processes due to the dynamic redistribution of resources. The implementation of the proposed methods can be used in logistics, courier services and transport companies to optimize the processing of requests, improve customer service and reduce costs. -
V.2(50), 2022
96-107At present, the “Afrosiyob” high-speed passenger train runs on the Tashkent - Samarkand, Samarkand - Karshi, Samarkand - Bukhara sections. In the near future, it is planned to launch freight trains on sections of the Bukhara-Misken route. On high-speed double - track sections Tashkent - Samarkand, Samarkand-Navаi, the movement of freight trains is combined with passenger trains. Which, in turn, negatively affects the throughput of stations and hauls. In connection with this, the actual issue is the movement of freight trains on these sections. Additional research is needed to increase the capacity of sections where freight and high-speed passenger trains run. The article considers options for the aerodynamic interaction of freight and high - speed passenger trains moving in one or the opposite direction. At the same time, the idea of the safe organization of freight trains during the movement of high-speed passenger trains was put forward. As a result of this study, the possibilities of carrying cargo trains in one direction or in the opposite direction are determined by ensuring the safety of movement on two-way parcels in which high-speed “Afrosiyob” high - speed electric trains travel. This makes it possible to develop recommendations for more effective use of the ability of parcels to conduct trains. When calculating the aerodynamic interaction, scientific ideas put forward by scientists from Europe, the USA, Russia and other countries were analyzed. Methods for solving the Navier - Stokes equations using existing programming models are described. -
V.4(52), 2022
96-105Based on the proposal for the formation of a railway track for operational deployment without ballast using a sub-rail base with a viscoelastic element forcedly filled with Newton's fluid and laid on an unprepared surface without ballast, an example of calculating the interaction of a wheel and a rail with this element based on the energy method is given. The possibility of using the design of the under-rail device for the operational laying of a railway track in difficult conditions on an unprepared surface without a track ballast layer is substantiated. The elastic dynamic impact of a wheel on a rail with initial speeds along a sub-rail base in the form of a box with shells laid on an unprepared surface is considered. The kinetic energy of a wheel hitting a rail laid on the proposed under-rail base passes not only into the potential energy of deformation, but also into the energy of wave and oscillatory processes. To improve the accuracy of solving the problem of dynamic impact, the transition of a part of the energy into the energy of local deformations in the contact area of the wheel with the rail is taken into account. Within a short period of time after touching the wheel at a certain speed, all elements of the rail acquire a certain strain rate. It is assumed that at the moment of contact with the wheel, the rail does not change its original shape, and the decrease in the speed of the wheel occurs due to local deformation of the materials of the contacting bodies; this period of impact will last until the velocities of the two bodies are equalized, after which the shape of the middle surface of the rail, modeled by a Bernoulli-Euler beam, will begin to change. Since the kinetic energy of the wheel is converted into the potential energy of bending, it is taken into account in the calculation to take into account the mass of the impacted body as the load of the wheel on the rail. -
V.2(14), 2013
96-102The current state of technological radiocommunication systems was analyzed, prospects of their development were shown in the article, and the necessity of further use of analogue radio communication channels was substantiated. Statistical data analysis of radiocommunication equipment failures used on the South Urals Railway is fulfilled. -
V.4(40), 2019
96-105Recently, for the analysis of complex nonlinear processes, more and more attention is paid to the mathematical apparatus of wavelet transform. This is due to the fact that unlike the traditional Fourier transform, the wavelet transform provides information about the signal under study in the time-frequency domain. The purpose of research is to analyze and simulate a non-sinusoidal non-stationary mode based on the packet wavelet transform, the use of this method for transmitting the digital data stream of the signal under study. The simulation was carried out using the software package Simulink. In the study found that packet wavelet transform with high precision allows to determine the presence of higher harmonics in the power system, the efficiency of using wavelet transform to compress digital data stream of the test signal. -
V.3(19), 2014
96-104The article solves the problem of optimal selection of rolling stock within groups according to the criterion of minimum sum of squared deviations of the current values of a given metric on the evaluation of their mathematical expectations for group objects. The solution obtained on the basis of methods based on ideas integer programming using Boolean variables and concepts of the relation between objects and between groups of objects. -
V.2(22), 2015
96-101Recently, during overhaul of the railway track using modern materials such as geotextiles and penoplex. In turn, they make significant changes to the structure of the ballast, t. To. Are almost insulators. OSTU experimentally it has been ascertained that the contact resistance in the case of using a new type of cloth can be raised to 45 - 150 Om*km. Obviously, this leads to a significant increase in the capacity of the rail relative to a distant ground and can cause injury to personnel operating the traction members network. To determine the capacity of the rail at any point area must take into account the redistribution of power in the elements of the rail network, ie. E. In the rail and the transition resistance «rail - the land». The rail network is characterized by longitudinal rails Zp kilometricheskim resistance, transition resistance «rail - land» rp-s, and the characteristic impedance ZB kilometricheskim spreading factor γ rail network. Analysis of the results lead to the following conclusions: 1) contact resistance «rail-to-earth» has a significant impact on the value of the potentials arising on the elements of reverse current flow circuit; 2) the growth of the resistance «rail-to-earth», associated with seasonal fluctuations in soil resistivity, as well as in recent times, with the capital reconstruction of the roadbed, resulting in a significantly longer (up to several tens of kilometers) area, for which the potential can reach hazardous the value of human life; 3) in the circuit mode on a rail (m. E. When a metal short circuit) almost always rail network will occur potentials exceeding admissible values for several kilometers in both directions from the point of fault, which leads to removal of the dangerous potential at all metal construction connected with the rail and therefore requires a review of the principles of grounding structures. -
V.2(42), 2020
97-102A mathematical model for diagnosing the state of solid insulation of high-voltage transformers based on an informational assessment of indirect indicators, i.e. entropy, for example, by the content of impurities of various gases dissolved in transformer oil, which allows to determine the technical condition without removing the workload. The values of the average information on the working and faulty state of insulation for various types of gas impurities are calculated. -
V.4(20), 2014
97-104In connection with the negative effects caused by the fault of the insulators used in an overhead power transmission line of 6 - 10 kV, it is suggested controlling a condition of a post insulator by the device that responses when breakdown current goes through an insulator. The work of the device for identification of insulators defects is described. Equivalent circuits of an alarm device connection with an insulator in an overhead power transmission line are given. The basic processes, that occur in a system of a supporting insulator of an overhead power transmission line in a serviceable condition and if there is a defect in view of geometric capacitance, absorption current, steady leakage current and surface current of breakdown, are considered. -
V.4(44), 2020
97-104Determination of the methodical error in measuring the active energy loss in the dc traction network
The article is devoted to the issue of power loss measurement in DC traction networks. The purpose of the work is to define the indicators characterizing the degree of determining the energy loss values accuracy when using the method of restoration of the train situation. In the article the analysis of methodical error the value arising at measurement of power losses in a traction DC network is conducted. The occurrence of the error is caused by the indirect measurement method, which is based on the principle of synthesis of instantaneous circuits in real time. The synthesis is based on direct measurements of currents and voltages on the busbars of adjacent feeding and switching points, for example, a traction substation and a sectionalizing station. The data obtained are processed in accordance with the algorithms adopted in the article, as a result of which the coordinates of loads and their current consumption are calculated. In the process of synthesizing instantaneous circuits, it is possible that such a train situation may occur, which will lead to the emergence of a methodical measurement error, due to the peculiarities of the logical and mathematical apparatus of the train situation recovery method. In this paper, has been performed a probabilistic analysis of the possibility of occurrence of methodological error when several traction loads will be present simultaneously on the measuring section, that is, the dependence of the occurrence of the measure of uncertainty on the daily size of train traffic and the dependence of the occurrence of the measure of uncertainty on the minimum inter-train interval. As a result of the study, the proposed method application the limits were established by energy loss measurement the permissible error the criterion. The methodological error the value of the measurement at different variants method of movement on the railroad studied section was assessed -
V.3(43), 2020
97-107New activities have appeared in Russia as a result of the structural reform of the railway industry. Operation of rolling stock is one of them. Operator companies have assumed this function, but now there is a surplus of rolling stock in the transport market. There is a need to develop methods and algorithms to improve the efficiency of this activity. The aim of this work is to analyze the activities of the owners of rolling stock, their organizational structure, the situation on the transport services market and identify directions for business diversification. Theoretical studies in the field of car fleet management are considered in the work. As a result, the main functions of the operator companies were identified. An assessment of the state of the market indicates that operators are pursuing a client-oriented policy and are gradually expanding the range of services provided. Technological outsourcing as a way of diversification was presented in the final part of the work. It enhances the quality of the operators' services. -
V.3(47), 2021
98-106For a radical solution of the issue of extending the service life of wheelsets of the freight cars, it is proposed to weld not only serviceable wheels, but also wheels to be pressed against an unacceptable rim thickness. It is shown that in multilayer surfacing, the possibility of obtaining high quality metal becomes more difficult, and heating of a thin rim can have an adverse effect on the gap between the inner surfaces of the wheels. The purpose of the work is to optimize the technological parameters of the multi-electrode surfacing mode, determine the amount of warpage of the wheel disk and study the quality of the deposited metal during operational tests of wheel sets. Experimental surfacing was carried out on the optimal parameters of the multi-electrode process, and a method for measuring the value of wheel warping in conditions of multilayer surfacing was proposed. The results of studies on the influence of the multi-electrode surfacing process on the metal structure and wheel warping are presented. It is shown that under the optimal surfacing mode, favorable conditions are created for obtaining fine-grained structures in the near-seamed zone. Field tests of the freight cars wheel sets were carried out to determine the efficiency and reliability of the method of automatic multi-electrode surfacing of the wheel rim. The task of the tests was a comparative assessment of the resistance of the wheels under study to defects and wear. The implementation of the task involved obtaining data for the wheel sets being researched on the number of cases of wheel failure due to the insufficient quality of the welded surfacing metal. It was found that wheel warping does not cause any dangers that threaten traffic safety, and the weld metal has the necessary resistance to cracking under the action of operational loads. -
V.1(41), 2020
98-107This article presents the rationale for the need to change the methodology for determining the absolute and relative values of energy losses to train traction. It is shown that when determining the relative value of the losses, it is necessary to take into account the amount of recovery energy returned to the contact network by electric rolling stock meters. To increase the accuracy of determining the absolute value of losses, it is necessary to take into account the energy consumption for the needs of the traction power supply system for prophylactic heating and smelting of ice on the wires of the contact network, as well as to ensure uninterrupted voltage on inactive electrified sections of railways. A formula is proposed for estimating the component of electric power losses in the contact network from the flow of energy recovery taking into account changes in the methodology for determining the loses of electric power for train traction. -
V.1(33), 2018
98-109The article discusses the process of developing an adaptive model of energy management of the railway enterprise on the basis of production rules. An algorithm for flow control of fuel and energy resources (FER) of the enterprise of the railway industry using mathematical apparatus of fuzzy logic.Proposed to use the base rules of fuzzy conclusions to assess the adequacy of the developed model of management. -
V.3(51), 2022
99-112In this article, the currently existing methods for determining such a technical parameter as the sliding friction coefficient were considered. The coefficient of friction is one of the main parameters characterizing the operation of tribological pairs of any engineering system. Stable and efficient operation of tribological pairs in such systems, along with high strength and fatigue characteristics, are not only the basis of safety, but also a promising direction in terms of economic benefits in the design and operation of various devices and systems. Accordingly, this area of research is very relevant for the railway industry, and for railway rolling stock in particular. This is caused by a large number of friction pairs in different nodes of passenger and freight cars, locomotives, ensuring safe and uninterrupted movement of rolling stock as a whole on iron drogs. Tribological processes are important both directly during movement and during braking processes. In this matter, the factor of determining and analyzing the sliding friction coefficient comes to the fore. One of these friction pairs is the «pad-wheel» system, which is the executive body of the braking system of a railway train. Optimization of contact in this system is one of the determining factors for the growth of braking efficiency during braking, increasing the working life of the elements of the friction pair, reducing the likelihood of defects. The search for new approaches to the study of friction issues is a direct catalyst for scientific and technological progress in the engineering industry. -
V.1(17), 2014
99-109The article provides a brief theoretical analysis of railway vehicle with nonlinear elastic elements. Considered distinctive features of spring suspension electric locomotives of the old and the new generations. On the basis of differences of a calculation scheme and derived a mathematical model of vertical dynamics of conditional «uniaxial» electric locomotive of new generation allows to estimate the critical speed train crew and indicators of its dynamic qualities. -
V.3(39), 2019
99-110The article outlines modern approaches to determining the maximum permissible continuous current of current collectors when stopping and in motion. The features of techniques that reliably take into account operational factors when conducting tests in laboratory conditions are considered. A mathematical model is given for studying the distribution of current load in emergency mode of breaking a current-carrying shunt. -
V.2(30), 2017
99-112The structure of a complex of locomotive safety devices (CLSD) is analyzed. A comparison of technical characteristics and design features of ground stationary and transport antennas of the receiving equipment of the global satellite radio navigation system (SRNS) is made. On this basis, the importance of using SRNS in the CLSD structure is shown. It has also been shown that the decrease in locomotive positioning errors associated with the need to increase the signal-to-noise ratio at the input of the receiver can be achieved by the use of active phased array antennas (APARs). APAR are able to form narrowly directional patterns with the commutation of their maximum directions in accordance with the coordinates of the constellation's navigation satellites. Features of the formation of narrowly directional patterns and the possibility of controlling them in a linear and flat uniform APAR are considered. It is shown that the use of APAR in the ground-based equipment of the user is associated with the need: a) changing the approach to designing it for specific applications, - a flat surface of the required size should be provided in the design; b) the modernization of the algorithm for receiving and processing SRNS signals, which must take into account the finite switching time of the radiation patterns, the angle of the mask, the number and coordinate distribution of the navigation satellites in the working constellation. -
V.1(29), 2017
99-105Now there is no efficient decision to estimate a corrosion condition of an underground part of reinforced concrete support of contact network which is not demanding digging of a support. This problem makes actual a task of development of a hardware and software system of definition of a corrosion condition of an underground part of reinforced concrete support of contact network. As a result of work the software module allowing to realize panoramic shooting of an internal surface of an underground part of a support, to increase quality of the received images, to carry out searching of inhomogeneities and to determine their geometrical parameters, and also to make the analysis of the found inhomogeneities. Implementation of results of work will allow to reduce time and labor costs, and also to increase efficiency of diagnostic works on support of contact network. -
V.3(27), 2016
99-110Is executed the analysis of the special features of the process of the optimization of the complex systems of video surveillance and video registration in the territorially distributed objects of rail transport. Is proposed the procedure of setting optimization problem during the local level for the group of adjacent clusters into supers-clusters and the step-by-step optimization of entire system at the global level. The procedure of two-level optimization and the association of the adjacent information clusters of system into the supers-cluster make it possible to combine the methods of linear and dynamic programming for the optimization of the complex branched systems on the criterion of minimum expenditures. -
V.2(26), 2016
100-107The article considers one of the ways of improving the energy efficiency of AC electrical system railways 25 kV, 50 Hz. The proposed approach allows to determine the optimal location and capacity of an unregulated device for compensation reactive power according to the criterion of minimum active power losses in a traction electrical system. Modeling of trains on the site was made using instant schemes. Description of the traction power supply system implemented by the node potential method and Steinmetz’s symbolic method. Optimal value of reactive power for all possible locations of a compensating device was calculated numerically by an optimization method of Hooke-Jeeves according to the criterion of minimum active power losses in the traction network. The mathematical model allows to consider the elements of the traction network, schedules of trains, change of traction loads of electric locomotives, schemes of overhead network. The proposed approach was considered on the example test problem, which solution allowed to determinate the optimal location and required value of reactive power of an technical device. The placement of a compensating device in a certain place will allows to minimize the power loss in the contact network, track circuit and traction transformers from the flow of the reactive component of the current in average for all instant schemes with various traction loads. An unregulated technical device for compensating reactive power which is located between two traction substations reduces energy consumption for traction of trains on the 1 - 2 %.
