Кафедра електроніки, фізики та СМАРТ-систем
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Item type:Наукова стаття, Directed Formation of Quality, as a Way of Improving the Durability of Conjugated Parts of Friction Pairs(Springer, Cham, 2020) Tkachuk, Anatolii; Zablotskyi, Valentyn; Kononenko, Andriy; Moroz, Serhii; Prystupa, StanislavIn the article the research of possibilities of directed formation of indicators of quality is given, by selecting technological operations and appointment of corresponding processing regimes. Studied approach directed formation of quality, based on the elements of theories of technological inheritance and interference of quality, which can reduce the role of random factors and their complex combinations in the process of providing regulated quality indicators, which in turn reduces the field of dispersion values performance and improves the quality of processed details. It is noted that for implementation of directed formation it is necessary to determine technological parameters, with the help of changing the values of which, it is possible to control the values of their indicators, which evolve in the process of mechanical processing. This will completely eliminate or reduce the impact of those indicators that worsen the performance properties of parts. It was revealed that the nature of manifestations of technological heredity is influenced by the conditions of implementation and the type of technological operations. It is advisable to apply this approach in the initial machining operations in order to initialize the manifestations of those indicators that improve the performance of the parts in general.Item type:Наукова стаття, Influence of Technological Methods of Processing on Wear Resistance of Conjugated Cylindrical Surfaces(Springer, Cham, 2021) Zablotskyi, Valentyn; Tkachuk, Anatolii; Moroz, Serhii; Prystupa, Stanislav; Svirzhevskyi, KostiantynWear of any tribological pair leads to malfunction or failure of the entire mechanism. It is known that the process of wear of friction pairs occurs in three periods: running-in, normal wear, accelerated wear (destruction). Working surfaces of parts that are formed in the manufacturing process receive micro geometric characteristics (roughness, undulation), according to the regulated technological norms. These characteristics describe the properties of the technological surface topography. However, quantitative micro geometric parameters change as they evolve during running-in, and the surface receives a new operational relief that is stable for a long time during normal wear. It is an operational relief of conjugate surfaces that characterizes the qualitative properties of parts for a long period of operation. The running-in process, which is based on complex mechanical, physical, and chemical processes, determines the overall wear resistance of parts. After this period, the physical, mechanical, and geometric characteristics of the surface acquire optimal values corresponding to the operating conditions. Rational performance characteristics during normal wear can self-sustain, and they are continuously reproduced independently in the same values. This state of the surface layer is observed before the beginning of the third stage of the life cycle. Traditionally, to ensure regulated micro geometric characteristics of the working surfaces used grinding, smoothing, and lapping diamond pastes. At the present stage of development of equipment and technology in a row with the mentioned finishing operations, there is an operation of high-speed turning, which allows reaching high purity of surfaces with the lowest cost of the technological process.Item type:Наукова стаття, MODELLING OF DYNAMIC MODES IN A DC MOTOR FOR ELECTRIC VEHICLE(Polytechnika Lubelska, 2026) Lyshuk, Viktor; Tkachuk, Anatolii; Moroz, Serhiy; Yevsiuk, Mykola; Khvyshchun, Mykola; Prystupa, Stanislav; Zablotskyi, ValentynThe paper investigates mathematical models of a DC electric motor with independent excitation for electric vehicles and PWM as a speed control method. Differential equations of electromechanical state are written in normal Cauchy form. This representation simplifies the computational process, since integration is carried out by the explicit numerical method of Runge-Kutta of the fourth order, which is simpler than implicit and more accurate than single-step explicit methods. The symbolic programming language Force 2.0, which is a variant of the Fortran language, is used for modelling. Compared to mathematical packages of simulation modelling, it is convenient in terms of low time costs for compiling the program itself, since the program includes model equations together with initial conditions, a numerical method, and an integration procedure. The developed models take into account electromagnetic couplings of the motor's electrical circuits and make it possible to simulate dynamic operating modes. Such models can be used to analyse the operation of motors both autonomously and as an element of an electromechanical system, including valve converters. The operation and transient modes of a DC motor are simulated, the simulation results are given, and their analysis is presented. The results confirmed the correctness of the chosen approach to modelling and numerical methods, as well as compliance with the classical theory of electric machines.Item type:Наукова стаття, MONITORING OF LINK-LEVEL CONGESTION IN TELECOMMUNICATION SYSTEMS USING INFORMATION CRITERIA(2022-12-30) Yakymchuk, Natalia; Selepyna, Yosyp; Yevsiuk, Mykola; Prystupa, Stanislav; Moroz, SerhiiThe successful functioning of telecommunication networks largely depends on the effectiveness of algorithms for detection andprotection against overloads. The article describes the main differences that arise when forecasting, monitoring and managing congestion at the node levelandat the channel level. An algorithm for detecting congestion by estimating the entropy of time distributions of traffic parameters is proposed.The entropy measures of data sets for various types of model distribution, in particular for the Pareto distribution, which optimally describes the behaviorof self-similar random processes, were calculated and analyzed. The advantages of this approach include scalability, sensitivity to changes in distributionsof traffic characteristics and ease of implementation and accessible interpretation.