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V.2(34), 2018
13-20Annotaion. The relevance of carrying out research works on improving the regulatory and methodological base in the development of promising railroad rolling stock structures with the use of new structural materials with nonlinear properties during deformation (physical nonlinearity) is substantiated in the work. The possibility of using the finite element method (FEM) procedure for creating such constructions is considered. Dependence of stresses on deformations is approximated by a cubic parabola. This made it possible to obtain generalizations of the well-known relations and algorithms of the classical theory of FEM with a nonlinear relationship between stresses and deformations. The proposed technique was tested in the evaluation of the stress-strain state (SSS) of an aluminum gondola car under various standard loads according to the 1st design mode. The effect of physical nonlinearity on the SSS of a spiral beam of a freight gondola car of aluminum alloy AMg6 was estimated. The calculation of the stresses generated by the action of a longitudinal force with eccentricity shows that the stresses in the nonlinear approximation are 13% lower than the corresponding stress values obtained by calculation in the linear theory. The results obtained can be recommended for the development of pilot projects of new structures optimized for weight and strength characteristics. -
V.4(20), 2014
105-111Is 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. -
V.1(37), 2019
112-121In 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. -
V.2(30), 2017
113-123In 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.