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Features of the methods of calculation of a braking distance of the train applied now are considered. The main shortcomings of the most widespread method of definition of a braking distance on speed intervals are shown. Authors offered the new method of calculation allowing to consider critical parameters of process of braking (speed of a brake wave; character of an indicator diagram of the brake cylinder and mode of a brake; the actual initial speed for calculation of a way of action of brakes of the train). For verification of the offered method computer modeling is executed and the analysis of results of the different methods of calculation of braking length received at application is carried out. The new method allows to make calculation of braking length of the rolling stock more precisely.

A variant of application of a contact compensated chain suspension with levers and lateral current collection for a three-phase traction power supply system (TSTE) is considered. Two different-phase contact suspensions are located on different sides of the track axis. The electric rolling stock must have two current collectors that press on the contact wire from the track axis in opposite directions. The description of the design of the contact suspension as a whole and the main components, in particular, the fastening of the rods, which makes it possible to provide a vertical zigzag and limit the transverse movement of the contact wire, is made. At points at the supports, the levers are connected to the consoles and have a knot to create angular rigidity. In addition, the rotation of these levers is limited towards the axis of the path and in the opposite direction. This prevents the possibility of lashing of different-phase contact wires. In accordance with this design, a mathematical model of this contact suspension was developed based on the finite element method, which provides calculation in statics and dynamics, taking into account the current collector. To describe the pantograph, a common three-mass model is used. Based on the analysis of the results obtained using this model, the influence of the design parameters of the suspension, cross wind and the speed of the pantograph movement on the quality of the current collection is determined, the limits of applicability of the suspension under consideration, depending on the value of these parameters, are established. It has been determined that, in contrast to a conventional contact suspension with a vertical current collection, for suspensions with a lateral current collection, a side wind has a significant effect on the quality of the current collection. It is the wind speed that is the main factor limiting the possibility of using a suspension with lateral current collection.

Example of the methods to evaluate conditions and reserve of transverse stability in CWR curves under abnormal track maintenance is discussed in the article. The author presents the results of the research of this method and also its positive effect is described.

In article the problem of determination of length of turn of structures, the total loading capacity of the transport which isn't provided with freight, quantity of freight of the transport knot which is in a timepoint in a warehouse on the basis of definition of distribution of a random variable of the freight expecting loading or unloading, and also the free capacity of vehicles taking into account restrictions on the capacity of warehouses is considered. During the solution of a task the following assumptions are accepted: capacity of cargo handling devices of transport knot isn't limited; time of the translation of giving of cars for the pogruzoch-but-unloading front and back isn't considered. The structure is understood as conditional structure which loading capacity is equal to the total loading capacity of some party of real structures, and the moment of its arrival - to the arrival moment on transport knot of the last of them. The received results can be used for determination of optimum values of warehouse capacities and a technological stock of freight of transport knot at the set goods turnover.

The article considers the task of controlling the quality of work transport hub taking into account the performance given by stochastically independent Poisson counter and quasiresonance traffic flows. The problem is solved with the use of analytical and mathematical apparatus of Queuing theory. The results obtained in the article are supposed to be used to determine the forecast of the total free capacity of vehicles waiting for loading, the queue length of loaded vehicles (trains) in anticipation of unloading, the coefficient of use of useful volumes of warehouse complexes.