The work presents simulation models of the control and monitoring system, the study of the dynamics of the parameters of the elements of a hybrid car using simulation modeling in Matlab / Simulink environment is performed. A series-parallel drive of driving wheels is considered. The electric drive is carried out from an asynchronous electric motor. The model includes energy consumption regulation and control subsystems, calculation and state control of the battery, internal combustion engine, electric drive, mechanical model of the car, simulator of driver's influence on the fuel pedal, driving mode control system. The changes in the operating parameters of the hybrid vehicle components and the vehicle itself on the given driving modes are presented. The results obtained correspond to the real values for the selected class of cars.

This paper reports an experimental study that determines the dissipative properties of a pressure fire hose, the type of «T», whose inner diameter is 77 mm, under the static load conditions, taking into consideration the structural elements of the hose in the transverse direction. For this study, experimental samples were separated from the different sections of the hose. The study involved both the outer fabric reinforced frame and the internal waterproofing rubber layer of the pressure fire hose. A series of field experiments were carried out while stretching the samples under the conditions of static loading-unloading cycles. The tests included 7 cycles, which were carried out in a two-minute interval for the material of the hose. The study results showed that during the first two to three cycles, the materials manifest a short-term creep that stabilizes under modes 4‒7. The results from experimental research were approximated by polynomial trend lines. The deformation of samples demonstrated the curves that, under the conditions of cyclic loading and unloading, formed hysteresis loops. When analyzing the appropriate curves, it was found that, first, during the first two-three loading-unloading cycles the area of the hysteresis loops decreases, second, the inclination angle of hysteresis loops also decreased during each subsequent loading-unloading cycle. It was established that the dissipation coefficients of the hose material stretched in the transverse direction are significantly reduced under the first three test modes in the range from 0.49 to 0.37. At subsequent tests (cycles 4–7), dissipation coefficients stabilize at the level of 0.18 for the reinforced frame, and 0.316 for the rubber layer

Modern trends in the optimal and rational design of technical objects cross a large number of directions of their implementation. One of the interesting and promising directions is genetic and evolutionary algorithms (GА and EA). Authors promote the use of GА and EA as a tool for solving problems of optimal and rational design of complex mechanical systems. The relevance of highlighting modern methods, approaches and strategies for the implementation of GА and EA is described, as well as consideration of their applied implementation, which makes it possible to identify interesting directions of research that, with further adaptation or modifications, can be used to solve the problems of optimal and rational design of gearboxes, boxes gears and transmissions. The main general directions of the literature on GА and EA are highlighted, as well as the practical use of GА and EA in: technical and technological activities, physics, construction, water systems, nanotechnologies, analytical and simulation modeling, electrical and electronic systems, modeling of artificial intelligence and neural networks, information technologies, economic theory, administration and management, marketing, sociology, biology and medicine. This made it possible to understand the course of scientific thought on this issue, to determine the advantages and disadvantages of existing directions and approaches, and helped to choose the vector of further scientific thought, to decide on interesting approaches, strategies and methods. Considering certain features of EA, the authors prefer them. And in terms of strategies, hybridization with other methods, maximum saturation of all stages with "randomness" and the possibility of learning (memory organization) of the algorithm similar to neural networks are promising. Keywords: optimal design, research directions, genetic algorithms, evolutionary algorithms

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Contact interaction of structural elements has been studied in the case of nominally close (nearly matching) surfaces. A non uniform gap is present between the contacting parts. Contact pressure and contact spot depend on the shape of this gap. Correspondingly so does the stress-strain state of the contacting bodies too. Since the problem is essentially nonlinear, the contact pressure distribution and the contact zones change with the growing loads. The solution is qualitatively different to the case of perfectly matching bodies. For the latter case, the contact pressure is linearly proportional to the load and the contact zone is predefined. Hence for the real structures for which the deviation from the nominal shape is unavoidable the impact of these inaccuracies on the contact pressure distribution and the stress-strain state need to be taken into account. This problem is addressed in the paper by example of elements of stamping dies. Keywords: element of stamping dies, stress-strain state, contact pressure, contact interaction, variational inequalities, Kalker’s variational principle, finite element method, boundary element method