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Item type:Наукова стаття, Solving operational tasks in the design of video surveillance systems(2025) Bahniuk, Natalia; Terletskyi, Taras; Kaidyk, Oleh; Kostiuchko, Serhii; Kondius, InnaThe article discusses the problem of CCTV design, which consists in the constant change of recommended criteria for equipment selection caused by the continuous and rapid evolution of technologies. The results of the analysis of existing standards are presented and discrepancies are identified. This trend leads to the destabilization of clear quality criteria and the risk of unreasonable CCTV design. The paper highlights the methods and results of research into changes in the spatial resolution of images from a range of technical characteristics of video cameras based on the relevant theory, which is implemented analytically and confirmed by computer modeling using specialized software. The results of the study, obtained by calculation and modeling, indicated a general discrepancy in the data obtained, which does not exceed the permissible limits. The data presented in the study results will help designers make an informed choice of video cameras, which will reduce the risk of excessive design.Item type:Наукова стаття, The Original Method of Controlling a Computer Using Distance Sensors(2022-02-22) Savaryn, Pavlo; Strekha, Vadym; Brych, Mykola; Brych, Lesia; Kabak, Vitalii; Polishchuk, MykolaThe article provides a brief overview of human-computer interaction methods and systems, and the research made in this area. We have designed the architecture of the system and tested a method of controlling a computer using ultrasonic distance sensors. In the course of the experiment, the following problems have been solved: obtaining and processing data from several distance sensors, data transfer to gesture recognition algorithm, uncontrolled oscillations of sensor indicators. The suggested method of controlling a computer can be used in ubiquitous computing.Item type:Наукова стаття, Determination of stress concentration near the holes under dynamic loadings(2021) Maksymovych, Olesia; Solyar, Tetyana; Sudakov, Andrii; Nazar, Ihor; Polishchuk, MykolaPurpose. To develop an approach for determining the stress state of plate structural elements with holes under dynamic loads with controlled accuracy. Methodology. The study was carried out on the basis of the Laplace transform and the method of integral equations. Findings. An approach to determining the dynamic stresses at the holes in the plates is proposed, which includes: the Laplace transform in the time coordinate; a numerical method for determining transformants of displacements and stresses based on the method of integral equations; finding originals on the basis of Prudnikov’s formula adapted to dynamic problems of elasticity theory. The problem of determining the Laplace images for displacements is reduced to solving singular integral equations. Integral equations were solved numerically based on the approaches developed in the boundary element method. To find displacements and stresses, the Laplace transform inversion formulas proposed by Prudnikov are adapted to dynamic problems. The study on dynamic stresses at holes of various shapes was carried out. Originality. A new approach to the regularization of the Prudnikov formula for inverting the Laplace transform as applied to dynamic problems of the theory of elasticity has been developed. For its implementation: convergence of Fourier series based on preset stresses at the initial time is improved; the remainder is taken into account in the conversion formula. Practical value. A method has been developed for calculating the stress concentration at holes of arbitrary shape in lamellar structural elements under dynamic loads. The proposed approach makes it possible to determine stresses with controlled accuracy. The studies performed at circular and polygonal holes with rounded tops can be used in strength calculations for dynamically loaded plates. The influence of Poisson’s ratio on the concentration of dynamic stresses is analyzed.Item type:Наукова стаття, Multiprocessing as a Way to Optimize Queries. Advances in Transdisciplinary Engineering(2024) Khrystynets, Natalia; Melnyk, Kateryna; Lavrenchuk, Svitlana; Miskevych, Oksana; Kostiuchko, SerhiiDeveloping an effective web application involves the use of various methods and techniques to ensure fast and efficient processing of requests. Sometimes it is not possible to solve the problem of multiprocessing with a single tool, such as a programming language or framework. This work investigates the use of asynchronous methods of processing requests using queues. Job operation in background and non-background modes relative to the main web process is studied. Analytics are provided to analyze a web application with 13,000 requests to process daily. It is proposed to optimize the processing by using the Laravel framework and the Python server dual-tasking using the Supervisor tool on Linux, as well as using a task scheduler for each task. The paper presents positive findings about this algorithm, which contributes to the efficiency of web development and provides a great user experience on the website. Fast processing of web application requests can be a valuable competitive advantage for a business or organization. Research in this field helps to maintain their high competitiveness. In addition, the study of query processing speed is important in scientific research, as it contributes to the development of new algorithms, optimization methods and technologies.Item type:Наукова стаття, The Auxiliary Parametric Sensitivity Method as a Means of Improving Project Management Analysis and Synthesis of Executive Elements(2021) Kostiuchko, Serhii; Polishchuk, Mykola; Zabolotnyi, Oleh; Tkachuk, Anatolii; Twarog, BoguslawTo write differential state equations of investigated actuating devices in the needed Cauchy’s normal form, we must abandon the traditional theory of electrical circuits for the theory of electromagnetic circuits. In this work, the known and developed new mathematical models for the analysis of special states have been involved. For solving this problem, it is necessary, at first, to construct a mathematical model of the actuating device. This model is based on the construction of a monodromy matrix, and simulation of transient and steady-state processes at the same time. To make the numerical analysis more convenient, differential equations for models of electromechanical state are written down in Cauchy's normal form. The algorithm involves the study of transient and stationary processes by decomposing them into constituent parts using the mathematical apparatus of the classical theory of nonlinear differential equations, which are calculated in a relatively simple way. The transitional process is obtained as a result of the differentiation of state equations for given initial conditions. We obtain a steady-state process by the initial conditions that exclude transient response. Such conditions we receive by the iterative Newton method. The proposed method of auxiliary variation equations allowed bypass procedure of differentiation of matrix coefficients over the argument that ensured the possibility of the algorithm application of the method of parametric sensitivity. The method of analysis can be spread to more complex nonlinear systems, such as electric motors.