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The paper considers the use of simulation modeling in the reengineering of technological processes for repairing rolling stock units on the example of repairing a bogie model 18-578 of an open-top car. The most time-consuming sub-process of repairing the bolster of this bogie was considered as the object of reengineering. Three options for reengineering of this subprocess were considered, implying a complete replacement of the technological equipment currently in use at repair operations (positions) with more efficient positions of the subprocess. To substantiate the choice of the most preferable reengineering option, the values of such indicators of the functioning of the subprocess under consideration as its productivity per shift (throughput), the load factor of the resources used at the repair positions, the volume of work in progress at the end of the shift, the number of workers employed in production and the costs associated with the possible purchase of new technological equipment. Simulation modeling of the functioning of the considered sub-process of bogie bolster repair was carried out on the basis of the methods of the queuing theory. The construction of simulation models and their assessment of the above indicators were carried out in the Arena RockWell Software environment. When developing simulation models for each of the possible options for reengineering a subprocess, the discipline of its organization and maintenance was taken into account. In the article, for each of the reengineering options, the calculated quantitative estimates of the listed indicators are presented, obtained using the corresponding developed simulation models. The use of these assessments reduces the risks in the development and subsequent implementation of organizational and technical solutions associated with the modernization of the considered technological sub-process of repair of the bolster of a gondola car bogie.

Microminiaturization elements of communication systems contributed to development Internet of Things, which led the expansion of various railway transport services. One of the Internet of Things component`s is the wireless sensor network (WSN). Feature of WSN is a dynamically changing spatial and information network environment. It complicates the adoption of promptly reliable management decisions based on assessments of the states of network elements. One of the directions of making a reliable decision in a complex network environment on the WSN is using cognitive maps in the WSN control nodes. In this article discusses various models of cognitive maps for assessing the states of network elements and network processes, which can also be used for railway transport services.

Station radio communication is an integral part of the technical means involved in the organization of a safe transportation process. Increasing the signal power in places with a complex electromagnetic environment remains an urgent issue. A passive repeater can serve as a solution to this issue, therefore the purpose of this work is to test the possibility of increasing the signal power level using a passive repeater.The article provides an analysis of a passive repeater used as a device that improves the quality of radio communications in places with a difficult electromagnetic environment. The differences between the use of a passive repeater and active relay stations are given.An analysis of the existing methods for calculating the parameters of passive repeaters was carried out, on their basis, modeling and calculation of the parameters of a passive repeater were carried out for the development and conduct of research in real conditions at a railway station. The design, materials of manufacture of the passive repeater, as well as the measurement scheme in real conditions are presented.The study is based on theoretical calculations and performance checks in real conditions and comparison of the results obtained. As a result of the study, it was found that the use of a passive repeater in a complex electromagnetic environment makes it possible to increase the signal power level, thereby increasing the stability of radio communication.It was noted that it is necessary to refine the existing method for calculating a passive repeater, since the above technique was used when calculating passive repeaters over long distances. A variant of fastening passive repeaters without the development and installation of additional new structures is proposed, the need to organize further protection against overvoltage is indicated.The results obtained will be useful in the development of new radio relay communication lines and the modernization of existing ones for places with a difficult electromagnetic environment and rough terrain.

The influence of systematic failures to the functional safety of automated control systems of hazardous technological processes is considered. It is shown that stability ensuring of the process control system to systematic failures is an actual task for today. Approaches to increase the robustness to systematic failures recommended by IEC 61508 are presented. Special attention is paid to methods based on diversion. The functional diversity and technology diversity have been revealed in detail. Examples of using diversification in railway automation systems are given. The main problems of using diversification to increase resistance to systematic failures are formulated. The main advantages of using diversification are increased resistance to systematic failures and reduced risk of dangerous failures through the usage of diversified protection methods at the functional levels of the APCS. The disadvantages of using diversification are a significant increase in the costs of developing and automated process control system maintenance, the difficulty of confirming the different behavior of diversified channels in case of systematic failures, and the lack of an effective method to assessing the sufficiency of the obtained diversification for a given level of safety integrity.