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The article deals with the question of methodology stop imitation modeling when using modern instruments of mental resources, which are, for example, was Wednesday MatLab. In particular, analysis of factors that determine the duration of the simulation for a given level of accuracy desired results.

The article presents a universal energy-efficient stand for load testing of asynchronous traction motors, and DC motors. It is proposed to use two options of schemes for testing of traction DC motors with serial excitation and asynchronous motors, and traction motors DC parallel (independent) excitation and asynchronous motors, each of which allows you to implement energy-efficient test method - the method of mutual loading. Given the advantages of the use of the proposed stand. The calculation of the main parameters recorded during the test: currents, voltages and power are invited to perform with the help of mathematical models. Each of the mathematical models takes into account the work of the subjects of the asynchronous traction motors and traction motors DC series or parallel (independent) excitation) by the method of mutual loading: electrical and mechanical link. In conclusion, the article sets out the intended results from the implementation of energy-efficient universal stand for load testing of asynchronous traction motors, and DC motors.

The article presents an improved mathematical model of the thermal state of the pantograph head for calculating the temperature distribution when interacting with different catenary with a double contact wire. The model takes into account the unevenness of the pantograph contact pressure on the wires along the suspension span and between them, allows using the databases of the car-laboratory for testing the contact network, calculating the thermal conditions of the skid on various sections of electrified Railways, including transients between them. The paper presents graphs of the zigzag distribution density of the contact wire of the Moscow - Saint Petersburg high-speed line, and defines the transient and steady state thermal states of the pantograph head when the pantograph interacts with them.

A method to an assessment of influence on the expenditure of electrical energy for traction of trains, parameters of graphic time-table in the conditions of using the regenerative braking is being considered in the article. The retrieval of version with the minimal using of energy is based on the modeling of graphic time-table by different train-to-train intervals in the conditions of burst-mode access’ organization on the railway section. By results of modeling it is proposed to represent the derived dependence by changing of electrical energy’s expenditure on parameters of graphic time-table in the form of analytic function of several variables n-order forthe following using by normative plotting of movement for the purpose of curtailing electrical energy’s expenditure for traction on the trains.

The article is devoted to the development of a mathematical model for predicting time losses in railway container transportation. Losses are classified within the context of the lean manufacturing concepts: muda (waiting), muri (overburden), and mura (unevenness). The relationship between the magnitude of time losses, flow unevenness, and resource utilization was investigated using the mathematical tools of graph theory and queuing theory. An adapted Pollaczek-Khintchine formula was applied to calculate the average queue length and the expected container delay time. The proposed formula allows predicting the average time losses arising during container delivery, caused by the overburden of transport hubs and/or individual terminals, as well as container flow variability. Model verification was conducted based on real data from the Zabaikalsk railway border crossing point, demonstrating the adequacy of the forecast. However, improving prediction accuracy requires model modification by incorporating additional factors influencing queue formation, such as: service priority for specific flows, the non-deterministic nature of service speed, and other variables not accounted for in the current model version. Using the model, dependencies were established between a container's queue dwell time, the hub's utilization level, and the flow variation coefficient. The study showed that the impact of flow variability on the queue is more significant at high hub utilization levels. Therefore, under conditions of infrastructure shortage, it is critically important to ensure a reduction in container flow unevenness and uncertainty. Recommendations for reducing time losses were substantiated, including increasing throughput capacity, synchronizing train schedules, and distributing cargo along routes with minimal load. The conclusions have practical significance for container market participants, enabling them to predict delivery times and choose routes with minimal logistical risks and losses. The results can contribute to enhancing the overall operational efficiency of Russian railways.

The purpose of this article is to create mathematical models for a comprehensive assessment of the quality of repairs of collector-brush assembly drive motor vehicles, including an assessment of mechanical and switching components. The objectives of this study are to determine the linguistic variables based on the generated set of diagnostic features, including "beating of the working surface of the collector", "RMS heights collector lamellae", "amplitude of the first harmonic component of the profile of the collector", "the amplitude of the second harmonic component of the profile of the collector" "RMS heights collector slat excluding the first and second harmonic components", "minimum value of the second derivative of the profile of the collector function", "standard deviation of the second derivative of the profile of the reservoir function," "effective value of the higher harmonic components of the collector profile features" that have the greatest diagnostic value and determination of their membership functions, as well as the definition of the complex index of quality of repair and its components: complex index of quality of machining and integrated commutation quality index in the collector-brush unit of the traction motor. Solution of tasks performed using the mathematical apparatus of fuzzy logic through the use of statistical processing of the results of these pilot studies and the calculation of the diagnostic value of the measured and calculated parameters. As a result of the research formed the mathematical model of quality repair in the space of selected features using the apparatus of fuzzy logic for calculating the value of the proposed integrated indicators for arbitrary values of diagnostic parameters. The results may be used to control the quality of repairs of collector-brush assembly of traction motors of the rolling stock.

A new approach to modeling the operations of railway stations and junctions using Petri nets is proposed. This method enables process analysis both analytically and through simulation, considering the topological features, operational technology of the station, and the structure of the transportation flow. The article provides a detailed examination of key properties of Petri nets, such as boundedness, liveness, and reachability, as well as methods for their analysis. These properties are applied to solve practical tasks, including resource optimization, increasing operational efficiency, and ensuring railway station safety. The proposed model identifies bottlenecks, forecasts potential operational difficulties, and develops measures to improve station performance. Various modifications of Petri nets, including timed, stochastic, and colored nets, are discussed. Each type offers distinct advantages for analyzing the temporal, probabilistic, and structural characteristics and parameters of station topology and transportation flow. The paper presents a model of the throat of a railway station’s reception yard for train passage, including its reachability tree of possible states. Analyzing the reachability tree identifies operational constraints and the sequences of events leading to these states. The model also predicts potential operational difficulties and shortages of maneuvering resources by applying an analytical method based on Petri net matrix analysis. This approach enables large systems, such as complex technical railway stations or junctions, to determine individual critical states that could lead to undesirable events without simulating all possible states.

Electric power installation of a special self-propelled rolling stock used in the power supply divisions is considered in the paper; the expediency of its use for the analysis of the main energy indices, in particular, the evaluation of the efficiency of electro-hydro-mechanical units at separate and joint operation, is shown. To assess the energy efficiency, an integrated efficiency factor has been proposed that allows to account the energy parameters of electrical installations operating in various modes. Recommendations have been given to increase the power factor of electrical installations.

The paper presents a calculation of the magnetic field over the cable with damage. The cable with damage is replaced to equivalent circuit «conductor - shield». The conductor and the shield is considered as two single-wire lines, loaded on the characteristic impedance to avoid reflections. For this equivalent circuit defined sine wave signal change in the conductor and the cable shield. These results indicate that in cable fault location conductor current is significantly changed and shield current reaches the maximum value. The values of the shielding factor is determined at dif-ferent frequencies for the continuous tubular aluminum conductor and steel spiral conductor. The magnetic field is determined on the earth surface over the cable with metal shield having a «con-ductor - shield» damage taking into account the shielding factor. The results show that the module and phase of magnetic field is incremented in the cable fault location, which can be fixed on the earth surface. The results of calculation will improve the methods and hardware for cable fault lo-cation searching.

To increase the level of mechanization and automation of the assembly processes of rail and sleepers, link assembly lines are installed at the production bases of the track machine stations. In 2012, a semi-automatic link assembly line of KB03 brand was introduced on the Belarusian Railways for the assembly of a rail-and-sleep grid on reinforced concrete sleepers with an SB-3 intermediate fastening. Increasing the productivity of this line is a priority area in research, since in modern conditions there is an increase in the volume of overdue railway track repairs. In the course of the study, it was determined that the most rational solution for studying the work of a link assembly line and finding ways to increase the productivity of its work is to use simulation tools. After studying the technical and other accompanying documentation, a simulation model of the KB03 assembly line was developed. Then the developed model was validated, during which it was found trustworthy and suitable for experiments. Based on the analysis of the results of the experiments carried out on the model, solutions were formed to control the production process of the KB03 assembly line to obtain the maximum increase in its productivity. The calculation of the economic feasibility of introducing the proposed changes and adjustments to the technological process of the link assembly line in production was carried out.

The article analyzes the components of the energy efficiency of regenerative braking and the factors influencing the effectiveness of the use of regenerative braking and energy recovery. Methods of evaluating the energy efficiency of recovery and the results of experimental studies of the effectiveness of recovery. Achieved justification for the use of the method of simulation modeling as a method for evaluating the potential of regenerative braking. It shows the sequence of the work.

Low-density railway lines (LDRL) make up almost 1/5 (15,353 km) (18.2 %) of the total length of Railways of JSC "Russian Railways". Currently, the operation of LDRLs in countries of Europe and in Russia is very expensive. This is due to the large number of manual management operations and the excessive need for staff. The solution to the problem of efficiency of use of LDRL in the conditions of market economy is one of the priority tasks facing the transport industry. Despite the fact that LDRL are poorly loaded (on average 3.5 pairs of trains per day) and, therefore, unprofitable, their content is subject to almost the same requirements as for the mainlines, including reporting requirements. The stationmaster and staff of LDRL are overloaded the reporting documentation. This requires the performance of work on the revision of the technology, standards of service and operating procedures LDRL. The purpose of the study is to reduce costs for the main types of activities by changing the technology of maintenance and operation of LDRL. The subject of this study is the operation and maintenance of the LDRL network of JSC "Russian Railways". The methodology of the conducted research is based on the system analysis and scientific generalization of domestic and foreign experience in operation and maintenance of LDRL. The article highlights the technological features of operation of the LDRL. The classification of lines with low-intensity traffic has been developed and the criteria for their assignment to the proposed types have been determined. The peculiarities of the organization of movement of trains, passenger and freight work for the LDRL of various types are presented.

The article carried out a comparison of the magnitude of the crest of the pressure forces on the rail in the curve sections of track and locomotives TG16 TG16M.

Article is devoted to actual questions of research of microstructure,physic-mechanical and tribological indicators blankets of friction couple "ring-sleeve of cylinder" under laser processing.Analysis of base defects of elements of cylinder-piston group of internal combustion engines,methods their reduction and rise of tribotechnical characteristics are conducted.Notes that different kinds of thermos and chemical thermal processing of working surface of link are most effective means of rise of wear resistance of couple "ring-sleeve of cylinder".Using of perspective technology of laser thermostrengthening is offered with this target.Offering technologies find greater application in automobile and technics of agricultural purpose. But purpose of ICE in aviation industry due to their specific exploitative and specific design features is limited.At the same time,they may have important practical meaning. Different variants of laser modification of surfaces of coupling in the context of CPG of aviation engine of ASH-62IR are offered and analyzed in article. Data of microstructural analysis of blanket,indicators of microhardness and wear resistance are adduced.Short description of tribotechnical laboratory-scale plant and methodic of conduct an experiment on base of comparative analysis of findings is given.Wherein tribotechnical indicators are compared with results of metallographical researches and physic-mechanical properties of modification layer,in particular with indicator of microhardness. Conduct of tribological researches determines that rise of indicator of wear resistance of friction couple "ring-sleeve of cylinder" observed at all researching regimes of laser effect with acconting of identified border conditions of processing for both elements of coupling.Maximum value of wear resistance is observed at laser thermostrengthening of both surfaces of couple on critical levels of density of laser energy.These levels do not case of appearance of microcracks in blanket.Wherein wearing qualities of modification surface of cylinder sleeve may increase by 4,5 - 5 times and wearing qualities of piston rings more than 3 times. Theoretical bases of mechanism of wear of thermos thermostrengthening surfaces which illustrate kinetics of increase their wear resistance in result of formation of microstructure of special blanket with increased bearing capacity,microhardness and improved conditions of wear of modification layer.Experimentally validated that the greatest wear resistance is observed in the friction elements at their mutual modifying their surfaces.

In article the new approach to calculation of power characteristics of quasiinvariant systems of suspension of mechanical objects different from other approaches by simplicity and logical clarity, however demanding the procedure of identification of the power characteristic of the compensator of external indignation of physical devices is offered.

The article suggests the method of monitoring the consumption of fuel for shunting and household works using the onboard systems. The first results of the evaluation of the effectiveness of the use of this method in the course of the experiment station «Omsk - Passenger»

Features of interaction of elements of a dynamic quencher of oscillations in the form of a rigid body with two degrees of freedom are considered. It is shown that the dynamic quencher is interpreted in structure of mechanical oscillatory system with object of protection as additional negative tie which can be presented by the generalized spring. Dynamic ruggedness of the generalized spring depends on the frequency of external indignation and defines manifestations of dynamic properties, characteristic for the modes of dynamic blanking out of oscillations. The generalized spring possesses properties of a quasi-spring that creates possibilities of various transformations of structure of system. Introduction of concept of the generalized transmission ratio of the lever ties arising between coordinates of the movement of elements of a dynamic quencher is offered. Forms of the transfer relations of lever ties are in univocity with system of the chosen coordinates. The transfer relations of lever ties allow to detail forms of mutual movements of elements of system. The method of creation of mathematical models is developed for an assessment of lever properties of movements of mechanical oscillatory systems.

Traction electric machines (TEM) of locomotives operating at the Eastern circulation range have insufficient reliability, mainly in terms of insulation breakdown, being one of the most important problems in the operation of electric rolling stock. This article discusses the method of drying wetted insulation by mobile and stationary electric heaters, which are used in the process of repairing traction electric motors of locomotives and electric trains. The problem of operating these installations is their low energy efficiency. With a constant power supply, the heating elements and the fan of the electric heater remain on during the entire drying process of the insulation, which leads to significant energy consumption, and the drying process is recorded by conducting paper workflow, recording the technical condition of the TU-152 locomotive in the log. To eliminate these shortcomings, the authors propose the modernization of the electric heating installation by introducing into it a microprocessor-based system for automatic regulation of the drying process with cloud storage technology. The article presents a block diagram of the proposed automated system, which will implement the three-cycle amplitude-latitude-discontinuous method of energy supply proposed at the FGBOU VO "IrGUPS" in the process of drying the wet insulation of the TED. Currently, cloud storage technologies have found their application in companies of various kinds of activity, it is being actively improved due to the constant increase in the amount of information that needs to be stored or transferred, and in addition, the user can have access to it from anywhere in the world. In recent years, the world has noticeably increased interest in the application of this technology in railway transport. As part of the modernization of the installation, it becomes possible to remotely control its operation, as well as store and process the information received on the drying process of wetted insulation.

The article discusses the criteria used to calculate the probability of failures of devices of the current collection system due to ice and frost deposits on a catenary. The purpose of the work is to determine the influence of climatic and operational factors (including the number of vibrating pantographs, pneumatic drums on electric locomotives within the boundaries of the Directorate for power supply and devices for mechanical cleaning of ice at power supply distances) on the probability of the occurrence of failures of the current collection system and their severity, which will allow to increase the reliability of operation of traction power supply devices in conditions of ice formation and the efficiency of investments by Transenergo and the Traction Directorate for the purchase of these funds. To determine the likelihood of failures of current collection devices due to the formation of ice on the wires of the contact network, it is proposed to divide all factors into climatic and operational. The choice of factors in predicting failures was carried out using a probabilistic Bayesian network based on statistical methods of data processing, as well as correlation and regression analysis. As a result of the research, the factors influencing the likelihood of failures of current collection devices have been determined, and their significance has been assessed using the calculated variances. A method is given for calculating the probability of failure for a conditional distance of power supply, which makes it possible to assess the adequacy of the equipment of Transenergo and Traction Directorates with devices for mechanical cleaning of ice from a contact wire, vibropantographs and pneumatic drums.

The aim of this article is an advancement of state estimation process of traction machines insulation. Diagnosis method brief analysis is given. The structure of traction machines insulation state automated full-service diagnosis system developing is offered, as well as the operation algorithm of the system. The algorithm of testing results estimation based on diagnosis characteristics group is given.

In the article the peculiarities and the advantages of using dynamic modes for diagnosing units of rolling stock. Specific examples of the diagnostics of separate units of the locomotive vibration, temperature, electrical parameters, frequency of rotation. The urgency of the task of developing diagnostic systems using the reference models.

The article proposes methodology for assessing the power loss in motor thrust bearings, the nodes of box, traction gear transmission. Revealed dependence between the power losses, the diameter of the tire wheel pair and the speed characteristic of the wheel-motor block. The results can be used to assess the technical condition and energy efficiency of traction rolling stock of Railways.

The results of measuring the components of electromagnetic interference on DC traction substations and AC.

This article describes the features of the calculation of the unsteady wave processes in the system of traction electric supply. Mathematical model for calculation of wave processes at contact networks based on modified Laplace transform combined with using Fourier series. Practiced modeling of power supply system for identifying characteristics of wave processes in traction networks.

In this article, with the help of software, the relationship between the structure of the material of the brake pad and the temperature distribution of thermal stress on it is established. Spatio-temporal distributions of thermal stresses were analytically determined for the surface layer of the friction element based on the model of a three-section brake pad with non-fixed edges. At present, shoe brake is widely used for freight trains. It converts dynamic energy into thermal energy using the friction between the pads and the wheel, and then dissipates the thermal energy through a heat exchanger. This process includes heat transfer, design features, mechanical characteristics, material properties and other. The article pays special attention to the brake pad pressure, braking mode, brake pad material and other factors. Modeling of thermal effects is the most important in the design of vehicle parts and assemblies. Thermal research is an important step in the study of braking systems namely railway vehicles, where it is necessary to breakе large masses, since the thermal load on the braked railway wheel prevails compared to other types of loads. In this paper, the thermal stress on the friction element of the shoe during braking is investigated. In frictional braking, the process of friction between the brake pad and the wheel occurs at the points of actual contact. The heat flow from the points of actual contact spreads over the entire geometric area of the block.