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The main aim of activities of the branches of vertically integrated Russian Railways JSC is enhancing of manageability and efficiency of business operations. At the current stage, the issue of optimization of costs for product transportation and facilities maintenance in the system of production and technological processes of the railway network has gained relevance. The purpose of this study is development of a mathematical model for the logistic system of transportation, storage, cargo-handling operations, facilities maintenance and reconstruction. Methods of spatial and dynamic modeling in the structure of end-to-end planning of operations were used in the study. Optimization criterion is aggregate cost minimization. Cost function is proposed in the form of local functions of multiple sections along the railway network. The modeling result consists in determining the plans of transportation and supply with minimum costs.

The development of national transport system impacts the performance of enterprises, and therefore, its viability in the market conditions. At the same time, the market is the exchange of goods and services, which is impossible without transport. Transport is a crucial component of the market infrastructure. It is essential to consolidate all the transport sectors into a multimodal transportation system, which would be convenient in terms of customer servicing, shipment time and accuracy, cargo safety, end-to-end information support, and financial relationships as well. Traditionally, the applied science deals with management of train and rail car traffic, stations, and rolling stock. In practice, carriers and cargo owners often have different priorities. The carrier needs to comply with routes and delivery time, while the customer is more concerned about shiploads, consistency in the delivery of carload shipments, and clearly scheduled delivery times. The problem of determination of ways to develop a unified transport environment facilitated by integrated multimodal transportation techniques is of a higher relevance. The purpose of this research is to identify certain stages of freight transportation, study the opportunities of applying various transportation techniques focusing on operating costs reduction, and to analyze the ways to improve routed transportation to the mutual benefit of both carriers and shippers. This work employs research methods to analyze freight transportation, and methods of mathematical modeling of the transportation process subject to introducing new techniques to minimize the number of re-classifications made on the route and reduce operating costs at unloading stations. As a result, the criteria have been identified to determine the choice of railroad transport operation activities subject to minimizing costs throughout the operating domain.

The purpose of this paper is to study the effect of the location and magnitude of opposite elevation on the occupancy level of the tracks of sorting park. The subject of the study is the effect of the magnitude and location of opposite elevation on the sorting tracks occupancy level. The object is the tracks of sorting park. For the study, a simulation model of the traffic of the cut in sorting park was used, taking into account the reverse movement, “SortPark”. On the basis of this model, it was concluded that when the target point is moved farther from the braking position, the distance traveled by the cut first increases, and then decreases. This is due to the fact that when stopping the cut on the opposite elevation, it can start to move backward. On the basis of this, it was concluded that the useful length of the sorting yard track for the first detaching limited by the point of change of gradient from grade to opposite elevation. In view of this conclusion, the formula for determining the sorting track occupancy level was improved.

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