Монография посвящена разработке методов совершенствования конструкции горок и технологии работы сортировочных комплексов станций. Книга предназначена для ученых, инженеров, аспирантов, студентов высших учебных заведений железнодорожного транспорта.
Наука та прогрес транспорту. Вісник Дніпропетровського національного університету залізничного транспорту, 2017, № 2 (68) ЕКСПЛУАТАЦІЯ CREATION OF EXPORT-ORIENTED NETWORK OF GRAIN ELEVATORS IN UKRAINEPurpose. The scientific paper highlights improving the efficiency of export rail transportation of grain cargoes in Ukraine by introducing shipper routing and concentration of loading at the terminal grain elevators. Methodology. According to the experience of the USA and Canada, one of the most effective ways to reduce costs in the grain to-port supply chain is a shipper routing of the rail traffic. Shipper routing for transportation of grain cargoes involves the concentration of their loading on the multiple junctions. The junctions are proposed to be selected with the use of cluster analysis methods. For the formation of the grain loading concentration areas the authors used methods of set theory and multi-criteria optimization. Findings. Based on agglomerative cluster analysis algorithm, the junctions on a network of Ukrainian railways are selected and the areas of possible concentration of grain loading are formed. DSU-algorithm allowed distinguishing the overlapping and non-overlapping areas of concentration. The problem of selecting non-overlapping areas of the grain loading concentration is formalized as the problem of multiobjective integer programming with boolean variables. The solution of this problem by a modified simplex algorithm allows selecting on the railway network of Ukraine 24 districts of possible grain loading concentration, which cover 70 stations and at minimal additional cost provide routing of about 7.5 million tons of grain per year. Originality. The originality of the work lies in the fact that the authors developed the mathematical procedure for selection of junctions and concentration areas of grain loading at the Ukrainian railway network, taking into account the economic efficiency of the process. Practical value. Application of the developed method of grain loading concentration for the formation of unit trains will significantly reduce the logistics costs in the supply chain of grain to Ukrainian ports for export and, consequently, increase its competitiveness in foreign markets.
The paper presents the research results of cuts braking modes on the gravity humps. The objective of this paper is developing the methods for assessment of braking modes of cuts under conditions of fuzziness of their rolling properties, as well as selecting the permissible starting speed range of cuts from retardant positions. As a criterion for assessing the modes of target control of cut rolling speed, it was proposed to use an average gap size on a classification track at the established norms of probable exceeding of permissible speed of cars collision and their stop in retarders. As a criterion for evaluating the modes of interval control of cuts rolling speed, using the risk of their nonseparation on the switches was proposed. Using the simulation modeling and mathematical statistics, the configuration of the range of permissible speed of cuts coming out from retardant positions has been set. The conducted researches allow simplifying the choice of cut braking modes in systems of automatic control of cut rolling speed. ВЕРОЯТНОСТНЫЙ ПОДХОД К ОПРЕДЕЛЕНИЮ ДОПУСТИМЫХ РЕЖИМОВ ТОРМОЖЕНИЯ ОТЦЕПОВ НА СОРТИРОВОЧНЫХ ГОРКАХ Аннотация. В статье представлены результаты исследований режимов торможения отцепов на сортировочных горках. Целью статьи является разработка методов оценки режимов торможения отцепов в условиях неопределенности их ходовых характеристик, а также поиск области допустимых скоростей выхода отцепов из тормозных позиций. В качестве критерия для оценки режимов прицельного регулирования скорости скатывания отцепов предложено использовать среднюю величину окна на сортировочном пути при установленных нормах вероятности превышения допустимых скоростей соударения вагонов и остановки их в замедлителях. В качестве критерия для оценки режимов интервального регулирования скорости скатывания отцепов предложено использовать риск их неразделения на стрелках. С помощью методов имитационного моделирования и математической статистики установлена конфигурация области допустимых споростей выхода отцепов из тормозных позиций. Выполненные исследования позволяют упростить решение задачи выбора режимов торможения отцепов в системах автоматического управления скоростью их скатывания.
Formation of multi-group trains is aimed at arranging their cars in a given order and is one of the mass operations performed at railway. In this regard, the reduction of the duration of shunting operations for the formation of multi-group trains is an urgent task for railway transport. In this paper, for a discrete deterministic-controlled system that simulates the operation of the flat yard, a mathematical statement of the problem of choosing the optimal order of multigroup train formation is obtained. The set of possible states of the system under study and the transitions between them are presented in the form of directed graph, which made it possible to reduce the problem of choosing the order of train formation to the problem of searching the shortest paths on the graph. An algorithm of searching the optimal order of train formation is proposed.
Summary. The paper considers the issues of bulk conveyance organization between industrial enterprises on schedule. Currently the movement of the main part of freight trains is performed on preparedness and occupation processes of separate schedule train paths by some terminals are not fixed. And, due to the lack of statistical material on the punctuality of the schedule for the movement of freight trains, research of the passenger trains movement with subsequent dissemination of results on freight movement were carried out by the authors. The values of the additional time reserves that should be included in the schedule of trains, and the schedule for the turnover of freight trains to provide conditional interaction of railroads and industrial enterprises in Ukraine were proposed. The obtained results can be used for the technical-and-economic calculations of transition effectiveness of industrial enterprises for maintenance on schedule as well as in the development of schedule on the initial stages of testing technology. ОЦЕНКА ЭФФЕКТИВНОСТИ ПЕРЕХОДА НА ОРГАНИЗАЦИЮ ДВИ-ЖЕНИЯ ГРУЗОВЫХ ПОЕЗДОВ ПО РАСПИСАНИЮАннотация. В работе рассмотрены вопросы организации перевозки массовых грузов между промышленными предприятиями по расписанию. Для того, чтобы обеспечить поступление поездов на станции назначения к заданному моменту вре-мени графики оборота составов должны иметь резервы времени, достаточные для парирования воздействия дестабилизирующих факторов. Для исследования каче-ства выполнения графика движения отдельными поездами использованы методы математической статистики. В настоящее время движение основной части грузовых поездов осуществляется по готовности и процессы занятия отдельных ниток гра-фика определенными составами не фиксируются. Поэтому, ввиду отсутствия стати-стического материала по пунктуальности выполнения графика движения грузовы-ми поездами, выполнены исследования движения пассажирских поездов с после-дующим распространением результатов на грузовое движение. Предложены значе-ния дополнительных резервов времени, которые должны закладываться в график движения поездов и график оборота грузовых составов, для обеспечения устойчи-вого взаимодействия железных дорог и промышленных предприятий Украины. По-лученные результаты могут быть использованы для технико-экономических расче-тов эффективности перехода промышленных предприятий на обслуживание их по расписанию, а также при разработке графиков движения на начальных этапах опробования технологии. 42
Purpose. The article is aimed to conduct a historical analysis of the development of analytical methods for standardizing the duration of shunting operations, as well as assessing their compliance with the existing operating conditions of railway transport. Methodology. The research in this article was carried out on the basis of an analysis of literary sources and methods of the theory of the organization of the operational work of railways. Findings. The standardization of the duration of shunting operations is one of the most important tasks of the theory of operational work of railways. The existing method of standardizing the duration of shunting operations developed in the first half of the 20th century and is used to this day. The performed analysis shows that the scientific principles underlying it generally correspond to the modern conditions of the railway transport. Additional research in this area can be associated with assessing the influence of the initial location of cars on the tracks on the average duration of shunting operations, taking into account the influence of length restrictions of the cars groups being moved, as well as monitoring the implementation of established norms by statistical methods. The article also shows that the values of modern time standards for shunting operations, in many cases, are set for technical means and technologies that were used in railway transport in the 50–70s of the 20th century and do not correspond to the operating conditions of real stations and sidings of industrial enterprises. Therefore, they require revision. Originality. In this paper, based on historical analysis, the process of development of methods for setting the time for shunting operations is described and the factors influencing the current value of norms are established. Practical value. The research results make it possible to identify the reasons for the discrepancy between the existing time standards for performing shunting operations and the real operating conditions of stations and sidings of industrial enterprises, as well as to establish the main elements of the methodology for standardizing the duration of shunting operations that require revision.
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