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The physicochemical properties of diesel fuel and methyl ester of rapeseed oil are reviewed, graphical dependencies of density, kinematic and dynamic viscosity, surface tension of diesel fuel and rapeseed oil methyl ester are shown when the temperature in the diesel cylinder changes, chemical indicators of methyl esters of rapeseed oil on the characteristics of injection and spraying of fuel.

The article analyzes the test schemes of induction traction motors by the mutual load method using DC generators as load machines and powered by a three-phase AC network with a frequency of 50 Hz. Features of functioning of each of the given schemes of mutual loading are considered. The disadvantages of these schemes are noted, due to the presence of excess equipment or the lack of short-circuit protection in the anchor circuit of the load generator and the complexity of its connection to the DC link. The scheme developed by the authors is proposed, devoid of the noted disadvantages of the known schemes and combining all their advantages, which is the simplest both in the power part and in controlling the process of connecting the armature winding to the DC link of a frequency Converter. A mathematical model of a test system consisting of an induction traction motor, a DC load generator and a two-link static frequency Converter is presented. The mathematical model of this test system is made up of parts corresponding to its individual elements. The presented mathematical model makes it possible to calculate the static and dynamic operating modes of the proposed scheme at the stage of development of an electrical complex for testing induction traction motors. Recommendations on the implementation of developments in the operation of induction traction motors in locomotive repair depots are given. The expediency of implementing the results of work in organizations-developers of test stations for induction traction motors is also noted.

The article describes trends in the technical development of fixing devices for containers, called a "fitting retainer". Containers have gradually conquered the transportation market in the USA, Europe and Asia. And each means of transport: road, marine and railway one needed devices to fix containers, because all participants of the transportation process are responsible for the safety of goods. In the period of the appearance of container transportations, commercial agreements between operators and transport companies played an important role, influencing the unification of overall dimensions and weights of containers and transported goods, which was a prerequisite to create fittings for containers and, as a result, fitting retainers for all means of transport. The domestic regulatory framework also required updating, monitoring a large number of flat wagon manufacturers and taking into account severe operating conditions of containers throughout the entire railway network. With the rapid development of the container transportation market on long routes from China to Europe and the transition to the technology of accelerated container train sets based on high-speed flat wagons, it becomes necessary to solve the issue of wind protection of empty containers and low loaded containers, taking into account the speed of up to 140 km/h. Well-known technical solutions from different manufacturers to fix containers in retainers of special shapes and with additional fixing through a retainer hole have been analyzed. An original technical solution of the fixing device is proposed, performed in the flat wagon opposite each fitting to install the container. By turning this device using man power, each corner of the container can be fixed to prevent empty containers from falling (tippling) from flat wagons when exposed to wind loads, which meets requirements of safety, operation and reliability of fixing the container in the flat wagon.

The article presents the results of the study of the influence of deviations of certain design parameters of bogie from established normative values on a relative offset from the crests of wheel pair in mezhdurelsovom space of railway transport. Such deviations occur in the process of the gradual wear of moving parts in real-world conditions of rolling stock and lead to a change of kinematic parameters of bogie. An analysis of dependence of lateral displacement relative to the wheelset of railway track from the difference between the diameters of the tapered surfaces of wheelset, skating from lack of alignment of wheelsets and difference coefficients rigidity of springs of bogie. The proposed mathematical model allows to not only diagnose technical condition of wagon bogies during their movements on the straight section of railway track, but also forecast the rolling stock maintenance dates the whole on the basis of position measurements of wheel pairs regarding railway track.

Analysis of the causes of errors of measurement of phase shifts of harmonic components in electrical railway traction networks and describes how to improve the accuracy of measurement.

Optimization of insulation of walling of building walls is proposed, taking into account the relationship of structural, heat engineering, operating parameters and economic indicators. The purpose of research is to determine the optimal value of the thickness of the insulation with the heat-insulating material of the object, taking into account the thermal energy released to it. The study used methods of mathematical modeling of heat transfer, an optimization problem. The results of the study of the influence of the thickness of the insulating material on the technical and economic efficiency of the building's consumption of energy resources and material costs are presented. The results showed a decrease in heat losses through the building envelope, consumption of heat and electric energy for the heating, ventilation system and reduced costs.

Is executed the analysis of the special features of the territorially distributed objects of rail transport for developing the systems of video surveillance and video registration. Is proposed the three-stage design procedure of such systems, at basis of which lies the separation of entire system into the zones of video surveillance, zones of video registration and the information clusters, which ensure the optimization of system on the criterion of minimum expenditures.

Is executed the analysis of the special features of the process of the optimization of the complex systems of video surveillance and video registration in the territorially distributed objects of rail transport. Is proposed the procedure of setting optimization problem during the local level for the group of adjacent clusters into supers-clusters and the step-by-step optimization of entire system at the global level. The procedure of two-level optimization and the association of the adjacent information clusters of system into the supers-cluster make it possible to combine the methods of linear and dynamic programming for the optimization of the complex branched systems on the criterion of minimum expenditures.

Is executed the analysis of the permissible range of the fluctuation of the phase of signal on the entrance of digital measuring device with a study of phase relationships in the tractive networks of the power supply of rail transport, characterized by high noise level.

The article describes three variants of the mathematical model of the sensitivity function of the magnetoinduction sensor for assessing the influence of various sensor parameters in the electromechanical system «wheel - rail - magnetoinduction sensor» for diagnosing the technical condition of the rolling surface of the rolling wheels of rolling stock in the process of its movement over the sensor. An example of an algorithm for identifying defects located on the surface of the wheel rolling circle is described. The proposed multi-vector mathematical model allows simulating various defects on the rolling surface of the wheel, developing and testing new algorithms for processing the output signal of the sensor on the basis of modern hardware and software. The implemented defect identification algorithm is based on the property of the centrally symmetric form of the sensitivity function of the magnetoinduction sensor and the allocation of a useful signal corresponding to a certain type of defect, based on the application of a mutual correlation function and the assessment of its maximum and minimum values in comparison with the specified thresholds and confidence intervals. The main requirement for the implementation of the model is the uniform movement of the train above the sensor along a straight section of the rail track. This article discusses only one of the possible digital signal processing algorithms, but the proposed model allows us to compare the efficiency of other possible algorithms identification of defects in the rolling surface of wheelsets. The developed model confirms the prospects of using magnetic induction sensors for identification of not only visible, but also hidden defects on the rolling surface of the wheel in the process of movement of the train.

In the work completed a study of shape vertices a unimodel probability density function (kurtosis) on the output of the nonlinear converter «phase shift - code, which is the most important parameter for evaluating conditions of finding mode to this function. To increase the accuracy of assessment shifts phases when there is high level of random noise is defined not only quality, but also quantitative dependence of the kurtosis probability density function on the output of the nonlinear converter «phase shift - code» of Standard deviation phase fluctuations of the signal at its input. The mathematical model of the distribution function on the output of the converter «phase shift - code» for research and implementation of algorithms improve noise immunity measure phase shifts between harmonic components of voltage and current in traction power supply rail transport networks.

In work done modeling and analysis of noise immunity of the proposed measurement method of phase shifts between harmonic components of voltage and current in traction power supply rail transport networks and estimation of maximum permissible noise level, where workability digital devices used to study phase shifts in these conditions. The simulation results have shown that the probability density function on the output of the nonlinear converter «phase shift - code» remains a unimode at any ratio range converter and standard deviation of the phase of the input signal. Implementation of researched ways of microprocessor-based digital device guarantees the stability and accuracy of measurement results in traction phase shifting networks of power supply of railway transport in the presence of high levels of industrial noise, nonlinear fast variable nature of the traction load, sparking the pantographs for electric locomotives in contact network and use recovery systems based on pulse converters.

To improve the accuracy of the diagnosis of the technical condition of rolling stock, it is necessary to develop new algorithms for the digital processing of signals coming from sensors at the time of the passage of the axes of wheeled pairs of wagon carts during the uniform movement of the train on the straight section of the railway track. The use of modern mathematical application software packages to model digital-based data processing algorithms reduces the cost and time of developing automated systems to diagnose the technical condition of the rolling stock of railways. To assess the accuracy of the fixation by the magneto-induction sensor of the moment of passage of wheel pairs axly, an asthigmatic model is proposed, allowing to investigate not only the energy properties of the sensor, but also the shape of the output signal, taking into account the real dimensions of its magnetic core. The developed model allows you to classify the pore. The developed model allows to classify the order of astigmatism model magnetoinduction sensor based on a set of discrete virtual sensors

The article presents the results of research of a point magneto-induction sensor based on a mathematical model, which allows you to increase the reliability of automated systems for diagnosing technical condition rolling stock in the course of train movement by improvement the accuracy of the initial information, that is, the moments of fixation passing of wheelset axles over magneto-induction sensors. At the first stage of developing a stigmatic mathematical model the analytical dependence of the value of the magnetic flux in the magnetic core and the output EMF value on resistance of the air gap between the sensor and the wheel crest. At the second stage of development of the mathematical model found time dependence of the magnetic resistance of the air gap between the core of the magneto-induction sensor and the comb wheels of a railway car moving along a straight track at a constant speed. On the basis of application the developed stigmatic model allows evaluating the energy parameters of magneto-induction sensors depending on the properties of modern magnetic materials. The simulation results showed that the MMF value is constant the magnet determines the main parameters of magneto-induction sensors, so the use of modern magnets based on rare earth they allow to eliminate the traditional disadvantage of outdated types of magneto-induction sensors, that is, to reduce their size and weight. The application of the proposed stigmatic model expands the scope of possible solutions to extreme problems for selection and justification parameters of magneto-induction sensors, helps to improve the accuracy of systems for diagnosing the technical condition of the car fleet and traffic safety on railway transport.