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This article presents an approach to planning rail freight transport taking into account the disruptions that occur during their implementation. The issues raised are related to the multi-aspect perception of factors influencing the organization of transport, in which immunity and safety play significant roles. The authors present an analysis of disruptions relating to the causes and effects of adverse events for selected traffic and operational parameters, including delays of freight trains in Poland from 2019-2022. The analysis of adverse events (accidents and serious accidents) in the rail transport system made it possible to present the rates of accidents when crossing tracks in prohibited places, at crossings on the public and separate networks, related to signals passed at danger events, and related to track works and the technical condition of rolling stock. In the case of the effects of adverse events, a rate was determined for freight train delays. The authors also developed a method for determining the value of disruptions in rail freight transport. A case study containing disruption quantification for a given freight train route is presented. The article emphasizes that a significant challenge in the rail transport sector is the proper organization of the operational activities of railway carriers concerning disruptions occurring during transport. [ABSTRACT FROM AUTHOR]

Vibration diagnostics is of particular importance in rail transport safety systems because the signals received from vibration sensors installed on rolling stock, bridges, tunnels, and other infrastructure objects have great diagnostic information potential. Despite this, in practice, there are cases when the adequacy of the results of the vibration control and diagnostics task is not ensured. The reason is that the sampling step of the vibration signal does not change when the train speed changes. Given the need to change the sampling interval depending on the train speed, this article proposes an adaptive technology for vibration signal sampling that allows the building of intelligent systems of adaptive vibration control of malfunctions in rail transport. [ABSTRACT FROM AUTHOR]

The proper technical condition of a vehicle and rail track in operation is a key aspect in terms of safety and travel comfort. This issue is of particular importance for operators and managers of rolling stock and rail infrastructure. Currently, many diagnostic systems have been developed to monitor the technical condition of selected vehicle systems or rail track from the viewpoints of both the vehicle and track. This article proposes the use of vibration signals in selected quantitative and qualitative analyses as the main diagnostic parameter. For this purpose, over a dozen vibration measurements were carried out during the normal operation of a freight wagon as part of a so-called passive experiment. Measurement points were located on the axle boxes of the wheelsets. The proposed research methodology served as a basis for comparative analyses of the selected operational cases that were investigated. The most important conclusion from the study is that it is possible to monitor the technical condition of vehicles and tracks in real time on the basis of measurements of vibration accelerations at the vehicle level. This directly increases the service life of rolling stock and optimises operating costs by changing the maintenance strategy to one that takes into account the idea of modern on-board technical diagnostics. Another important aspect is the possibility of the varied use of the proposed measurement system, depending on the purpose of the research, which is also associated with the diagnostician's experience in processing vibroacoustic signals and the utilisation of simple or complex quantitative and qualitative analyses. [ABSTRACT FROM AUTHOR]

It is shown that modern geometry cars, flaw detector cars and other track test cars provide reliable control of the technical condition of all hauls of the railroad track at "certain intervals of time". Their number is limited and therefore "continuous monitoring" of all hauls is almost impossible. At the same time, in real life, due to the impact of various factors, such as seismic processes, certain changes take place even a day after control. The authors consider one option for continuous monitoring of the beginning of changes in the technical condition of the track using intelligent tools, which allow one, by analyzing the useful signal and the noise from the soil vibrations caused by the rolling stock, to create informative attributes for identifying the technical condition of the track. The application of traditional technologies of correlation and spectral analysis and other methods for this purpose does not allow ensuring adequacy of the control results. This paper proposes a technology for extracting and analyzing useful vibration signals, the noise of vibration signals and the relationship between them. The estimates of both correlation and spectral characteristics of the useful signal and the noise are used as the main carriers of diagnostic information. Due to the simplicity and the reliability of implementation of the proposed technical tools, they can be easily installed in one of the cars of all rolling stocks, providing control of the beginning of changes in the technical condition of the track during their movement in all hauls. [ABSTRACT FROM AUTHOR]

In contrast to traditional systems for monitoring fault of the running gear of the rolling stock, this paper proposes a technology of noise control at the onset of defects. The authors consider the possibility of creating an intelligent system that can perform noise diagnostics with the indication of the beginning of the latent period of the initiation of typical defects preceding faults. To this end, using the noise technology, sets of reference informative attributes are created in the training process. The reference sets, in turn, are used to determine the condition of the object at the beginning of the development of defects by comparing them with current noise estimates. It also allows controlling the dynamics of the development of defects. [ABSTRACT FROM AUTHOR]

On the railroads in seismically active regions, the impact of frequent weak earthquakes accelerates the initiation of defects such as wear and tear, cracks and deformation due to fatigue. An analysis of the types and stages of initiation and development of defects preceding accidents at technical facilities has shown that the registration of the beginning of the latent period of transition of objects to an emergency state based on the results of traditional technologies of analysis of measurement information in the applied control systems in the field of railway transport is delayed owing to the difficulties of noise analysis. The proposed algorithms and noise analysis technologies allow forming corresponding sets of informative attributes to control the beginning of the latent period of accidents. Their use in intelligent noise control systems will improve the safety of this mode of transportation. To this end, it is expedient to create a subsystem for noise seismic hazard warning, i.e., a subsystem for noise control of the onset of the initiation and dynamics of development of changes in the technical condition of the rolling stock, railroad tracks, bridges, tunnels, and other railroad infrastructure facilities. [ABSTRACT FROM AUTHOR]

In the most developed countries, intensive studies are being carried out to utilize various types of electric machines such as synchronous motors with permanent magnets and traction motors with non-traditional magnetic systems on traction electric drives. Switched Reluctance Motors (SRM) are one of the most simple, reliable, and costefficient technology used in manufacture and operation. Its convenient traction performance, combined with the high overload capacity, makes its use promising for both freight and passenger rolling stock. Our research is directed to develop a control system for a four-phase SRM. The procedure of fuzzy-regulator synthesis is presented. A physical model of a switched reluctance drive is created, namely, it is a system of a wheel set and a motor. The efficiency of the control system with different types of speed regulators was checked and their main quality indicators were determined. According to the results of the analysis, it was found that the fuzzy regulator more precisely controls the regulated value. [ABSTRACT FROM AUTHOR]

In this article we consider the increase of the resource of wheelsets of cars and locomotives. We give general data on present research in the field of tribotechnical systems, and offer alternative variants of development of domestic tribotechnical systems for railway transportation, which can be useful to replace foreign systems. The systems capable of increasing the reliability of a railway branch are described. [ABSTRACT FROM AUTHOR]

A new approach is developed to ensure the stability of the coefficient of friction at different braking modes for the entire speed range of braking high-speed ground transport. The new approach is a combination of friction materials with individual effort effects on the brake disc. A brake pad design and its performance are confirmed experimentally. [ABSTRACT FROM AUTHOR]

Today modern locomotives of KZ4AС, KZ8A, ТE33А series were put into service in the Republic of Kazakhstan. In order to establish safe operating mode of these locomotives the admissible speed on the railway tracks of the Republic of Kazakhstan was determined. The admissible speed of locomotives was determined on the basis of analysis on the results of dynamic and railroad tests and calculations for stress of railway construction. [ABSTRACT FROM AUTHOR]

The publication reflects the research results of the rationalization of the rolling stock use of JSC LG Lithuanian railways to increase the reliability indicators of the freight diesel locomotive exploitation reliability. The comparative evaluation of the exploited freight diesel locomotive work duration, according to the technical documentation, by using comparative test results and indirect diesel reliability criteria approved in practice. An algorithm of work duration forecasting methodology has been created, as well as a programme complex of mathematic modelling. The differences of the results indicated in the experiment and modelled by computer do not exceed 5 ÷ 7%. The proposed and described methodology of the diesel locomotive exploitation load cycle dynamic indicator reduction, by the use of which the following is achieved: increase of the diesel work duration by 7÷10%, reduction of fuel consumption up to 10%, reduction of the load cycle dynamic indicators (increasing the fatigue stress of parts and units of the diesel) by 15÷20%. [ABSTRACT FROM AUTHOR]

This paper is focused on contemporary posibilities of replacement dieselpowered railcars by accumulator powered railcars in regional railway traffic. In the first part of the paper, there are described advantages and disadvantages of this replacement. In the second part are presented the simulation counts and the simulation results of the drive of an accumulator powered railcar on the railway line Šumperk - Kouty nad Desnou. At the last part of this paper is shown the experimental accumulator powered railcar, which was built at University of Pardubice, and the energy research, that is realized with this railcar at railway line Mladějov na Moravě - Hřebeč. [ABSTRACT FROM AUTHOR]

Breakdown of rolling stock axle-boxes if not detected in due time may cause a rail accident or disaster. At present, a lot of advanced technologies, modern equipment and devices, which “recognizes” faulty axle-boxes when the train is in motion, have been implemented. However, the timely identification of breakdown of rolling stock axle-boxes still is an acute problem, the initial stage of damage emergence being especially problematic. Presently, rolling stock axle-box breakdown is determined according to the higher than permissible temperature of the axle-box body. The article provides statistical data of dangerously heated axle-boxes, determined train delay durations, the number of delayed trains by danger level, and dependence of damage on the season. After systematization of data on axle-box damage and heating temperatures of broken axle-boxes, heating tendencies of axle-boxes of freight wagons are described. Finally, basic conclusions are given. [ABSTRACT FROM AUTHOR]

In the article we have developed the dynamic model of interaction of rolling stock during the movement, on the suspended monorail, taking into account the sidesway. We have received the motion equations, carried out their analysis and determined the own oscillation frequencies of rolling stock of suspended monorail. [ABSTRACT FROM AUTHOR]

The problem of SRM sensorless start is described. The new algorithm of traction switched reluctance motor sensorless start-up in a course is adduced. Results of physical modeling of the described method are given. [ABSTRACT FROM AUTHOR]

The article analyses the current traction rolling-stock used by „Lietuvos geležinkeliai‟ Plc. for freight transportation. The technical data of the above mentioned rolling-stock is explored and compared, and operation costs are estimated in the article. After the assessment of the forecasts of freight flows on the constructed railway „Rail Baltica‟, the algorithm for selection of freight locomotives was proposed. The efficiency of the locomotives operated on the railway is determined by three multicriteria evaluation methods: the sum of ratings, simple additive weighting, and the geometric mean method. Locomotives are valued in accordance with technical, economic and ecological parameters. The results of possible effective performance of the rolling stock have been determined by changing coefficient values of the criteria. Finally, basic conclusions are given. [ABSTRACT FROM AUTHOR]

The design method how to increase the reliability of the railroad underframe frictional dampers has been given. The new design for frictional wedge has been suggested, it helps to decrease both the wear of friction wedge and the deterioration of the connected with shpinton sleeve. [ABSTRACT FROM AUTHOR]

Any activity accustoms on the base of the general abilities which develop in this activity, and "special" abilities are the general abilities which have got lines of efficiency under the influence of requirements of activity. And the more technical is the activity, the bigger role in its realization is played by "special" abilities [8, 9]. Hence, definition of effective receptions of psychophysiological and psychological diagnostics should be combined with a finding of optimum ways of vocational training. [ABSTRACT FROM AUTHOR]

The paper presents some results of in-service tests on tram wheel set life. The measurements of wheel rim undercut and wear on the rolling diameter of tram wheel set wheels are a data base for calculating tram rolling wheel life in two aspects: wheel operation conditions and materials from which the wheels were made. [ABSTRACT FROM AUTHOR]

A mathematical model to select the best rolling stocks of trains is introduced. The parameters of income and cost of the passenger transportation by railways depending on the technical characteristic of used vehicles are thoroughly evaluated. The options how to reduce the cost calculated by a model in one of the specific routes of Lithuanian Railways are given and practical decisions are argumentatively given. [ABSTRACT FROM AUTHOR]

The article gives an account of the results of working out a generalized dynamic model of fixation of cargo with pads jointly with flexible and thrust elements. Working out a generalized dynamic model of cargo fixation is rather a complicated problem not in the sense of solving differential equations systems but in the sense of presenting them as a complex mechanical system "cargo -- pads -- flexible elements -- thrust bars". Generalized dynamic model of cargo with pads observed that this model represents technology of joint work of flexible and thrust fastening means of cargo on rolling stock. In particular, on the basis of this model there can be obtained the technology models of joint work of flexible and elastic fastening means of cargo without pads of fastening flexible elements of cargo with pads without thrust bars and also flexible fastening elements of cargo without pads and thrust bars at asymmetrical and/or symmetrical allocation of cargo in the wagon. A specific feature (novelty feature) of the proposed dynamic model is inclusion into the model of both cargo pads and thrust bars which are nailed to the wagon floor close to the butt and lateral sides of cargo. [ABSTRACT FROM AUTHOR]