Кафедра "Системний аналіз та інформаційно-аналітичні технології"

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https://repository.kpi.kharkov.ua/handle/KhPI-Press/7644

Офіційний сайт кафедри http://web.kpi.kharkov.ua/say

Кафедра "Системний аналіз та інформаційно-аналітичні технології" заснована в 1982 році.

Кафедра входить до складу Навчально-наукового інституту комп'ютерних наук та інформаційних технологій Національного технічного університету "Харківський політехнічний інститут". Випускники кафедри працюють у провідних ІТ-компаніях: EPAM, CloudWorks, DataArt, MedeAnalytics, NIX Solutions, CodeIT, Ciklum та багатьох інших в Україні та за кордоном.

У складі науково-педагогічного колективу кафедри працюють: 4 доктора технічних наук; 9 кандидатів наук: 8 – технічних , 1 – економічних; 4 співробітника мають звання професора, 9 – доцента.

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Зараз показуємо 1 - 20 з 660

About stability of the movement of the refueling vehicle equiped with digital system of brake forces distribution during the emergency braking
(Національний технічний університет "Харківський політехнічний інститут", 2021) Aleksandrov, Ye. Ye.; Aleksandrova, T. Ye.; Morhun, Ya. Yu.
The impact of enforced oscillations of the free surface of fuel in the car tank on the stability area of a closed digital brake force distribution system is considered. The object of the study is the process of stabilized movement of the tanker during the emergency braking. The subject of the study is a large tanker with a gross weight (3-3.5) *104 kg, equipped with a tank with a volume of (17-20) m3 and a system of direction stability. The goal of the work is investigation of the impact of transported fuel fluctuations on the stability of the refueling vehicle during the emergency braking and introducing of methods for selecting values of variable parameters of the electronic brake force distribution system to minimize it. Conclusion. Considering the oscillations of the free surface of the liquid in the mathematical model of disturbed movement of a closed system of stability significantly reduces the stability area of the system in the low frequency range due to the loop, the size and position of which depend on the filling level of the tank. Need to choose an envelope loop that according to different levels of tank filling.
Analysis of trends in UI/UX interface development and their impact on future user experience
(ТОВ "Друкарня Мадрид", 2023) Azarenkov, V. I.; Svintsova, D. O.
Application of Genetic Algorithms to Vector Optimization of the Automatic Control Systems
(Institute of Information Theories and Applications FOI ITHEA, 2009) Severin, Valeriy Petrovich
Methods for calculation of quality indexes for automatic control systems are presented. For the optimization of quality indexes defined only in a stability domain a vector objective function of varied parameters of the system is proposed. The stepwise principle of successive satisfaction of constraints for the passage into the definition domain of quality indexes is considered, as well as a rational mechanism of its realization in the form of the priority optimization of the vector objective function. For the optimization of the vector objective functions genetic algorithms as vector optimization methods are presented. Their application allows one to steer the optimization process from any initial point of the space of varied parameters into the stability domain of the system and to find the optimum of the quality indexes in this domain. The efficiency of the proposed application of vector genetic algorithms for the quality indexes optimization is confirmed by computational experiments.
Automating the development of iterative tests and exam tickets in latex
(2023) Azarenkov, V. I.
Consensus control of multi-agent systems with input delays: a descriptor model approach
(Lviv Polytechnic National University, 2019) Lyubchyk, L. M.; Dorofieiev, Yu. I.
This paper addresses the consensus control design for multi-agent systems with input time delay, which is unknown but bounded. Descriptor transformation is used to obtain a model without delay for closed-loop individual agent. The sufficient conditions for global consensus under directed communication topology are identified using Lyapunov–Krasovskii functional. To analyze the stability of the networked multi-agent system based on the relationship between the agents, the Lyapunov function method using corresponding comparison system is used. The effectiveness of the proposed control design method is demonstrated by a numerical simulation example.
The deferred solutions scheme for the problem of finding a Hamiltonian cycle solving
(ТОВ "Планета-Прінт", 2021) Prokopenkov, V. P.; Kozhyn, Y. N.
Development of a Method for Generating Material Input Flow for Transport Conveyor Using Experimental Data
(CEUR Workshop Proceedings, 2023) Pihnastyi, Oleh; Sobol, Maksym; Burduk, Anna
This work is devoted to the development of a method for generating values of the input material flow of a transport conveyor based on experimental data. The experimental data are represented by a single realization of the material flow for a sufficiently large observation time interval. The statistical characteristics of the implementation of the input material flow are studied. To determine the values of the correlation function, the numerical integration method was used. To analyze statistical characteristics, dimensionless parameters are introduced that can be used to construct similarity criteria for input material flows. When constructing the generator of the input material flow, the canonical expansion of the random process in orthogonal functions is used. This decomposition allows transformations to be carried out over a stochastic input flow of material. It is assumed that the implementation of the input material flow is formed for the steady state of material extraction. As a zero approximation when constructing generators of the input material flow values, it is stipulated that random measurements in the canonical expansion have a normal distribution law. Orthogonal functions are represented by a normalized Fourier series. It is shown that centered random variables of the canonical expansion have dispersion values that are defined as expansion coefficients of the correlation function in a Fourier series. Analysis of the generated material flow realization shows that its values have a distribution close to the normal distribution. An example of realization using a random value generator for the input material flow is presented. The accuracy of the realization is determined by the number of terms in the Fourier series expansion and the accuracy of the numerical integration method.
Development of advertising web pages of sites
(ФО-П Шпак В. Б., 2023) Ugrimova, E. S.; Azarenkov, V. I.
Development of templates for text documents of the educational process in the publishing system LATEX
(ТОВ "Друкарня Мадрид", 2023) Azarenkov, V. I.; Paziura, K. S.
Development of the controller for the quadcopter Finken in simulation enviroment VRep
(NTU "KhPI", 2016) Severin, Valeriy Petrovich; Nikulina, Elena Nikolaevna; Buriakovskyi, Vladyslav Serhiiovych
The problem of control of quadcopter Finken, that was created at department of Intellectual systems at Otto von Guericke University Magdeburg, was presented. The simulation environment VRep as 3D robot simulator was reviewed. The general mathematical model of copter was presented and the model of quadcopter Finken was created in VRep simulation environment. The principles of working continue and discrete PID controllers were described and analyzed. The models of motion of quadcopter Finken were reviewed and implemented in simulation environment VRep. The model of recommended PD controller for quadcopter Finken was described and implemented. The test flights were done and the stable flying motion of quadcopter was received. The conclusions about possible use such a model was made.
Dynamic Pricing Strategies for Discrete Perishable Products
(2022) Melnikov, O. S.
The paper is devoted to the development of a dynamic pricing strategy for the sale of products whose value expires with time. Sales of discrete goods to heterogeneous consumers who have at most a unit demand for sold goods is considered. This type of demand structure makes it possible to describe the optimal pricing strategy using a simple system of recursive equations, which allows for an analytical solution in some special cases. For the general case, a numerical algorithm has been developed for finding the optimal solution as a function of time to expiration and remaining stocks of unsold products. The proposed strategy is compared with the fixed-price policy and estimates of economic gain from employing dynamically adjusted prices are obtained. Simple heuristics for sales management under conditions of incomplete information are also proposed.
General methods for studying input material flows of conveyor transport system
(Odesa National Maritime Academy, 2023) Pihnastyi, O. M.; Sobol, Maksym
A transport system model based on neural network can be used in the synthesis of algorithms for optimal control of a conveyor section flow parameters, in order to reduce the specific energy consumption of material transportation.
Heuristic Rules for the Dynamic Pricing Problem
(Vilnius University Press, 2023) Melnikov, Oleg
This paper is devoted to the development of heuristics for the dynamic pricing problem. A discrete time model of dynamic pricing on the fixed time horizon is proposed. It is applicable to products that satisfy two properties: 1) product value expires at a certain predetermined date, and 2) consumers demand at most a single unit of the product. This type of demand structure allows deriving a simple system of recursive equations for optimal prices using dynamic programming techniques. Optimal pricing policy is expressed as a function of time to expiration and inventory levels of unsold products. An analytical solution to this problem was obtained for special cases, while for the general case, a numerical algorithm has been developed. Qualitative characteristics of the optimal pricing policy are established, and their implications for dynamics of inventories and prices are discussed. Based on these observations, a simple heuristic rule for dynamic price adjustments is proposed. Performance of this heuristic is evaluated against the optimal dynamic and fixed-price policies using Monte-Carlo experiments. Results demonstrate high efficiency of the proposed heuristic strategy and its even simpler derivatives. Heuristics’ adaptability and ease of implementation should make it suitable and attractive for small and medium businesses.
Inversion of Dynamic Systems for Certain Classes of Signals
(2019) Kutsenko, Alexander; Kovalenko, Sergey; Tovazhnyanskyy, Vladimir
Methods of inversion of dynamic systems are widely used for solving problems of control of mechanical and electrical systems. Solving the inversion problems raises a number of difficulties related to the high sensitivity of the results with respect to the accuracy of setting the parameters of a mathematical model of object parameters, instability in controlling non-minimum phase objects, and violation of the conditions of physical realizability. In this paper, an approximate method of solving the inversion problem for linear stationary dynamic systems is proposed which is largely free from those disadvantages. The method is based on the representation of the input and output signals by their approximations in the linear space of specially selected D-functions of time. The feature of the proposed method of inversion of dynamic systems is the representation of multidimensional polynomials approximating the input and output signals as a product of rectangular matrices and a vector of powers of time. Mathematical models of linear dynamic systems in the form of differential equations in the state space and in the equivalent input-output form, as well as SISO and MIMO dynamical systems are considered in the paper.
Method for Determining Statistical Characteristics of Input Material Flows of Transport Conveyor
(2023) Pihnastyi, Oleh; Sobol, Maksym
This paper is devoted to the study of the statistical characteristics of the experimental values of the material flow entering the input of a conveyor-type transport system. The paper considers the statistical analysis of the input non-stationary stochastic material flow, represented as a superposition of non-stationary deterministic and stationary stochastic material flow with ergodic properties. The problems of typification of the empirical input material flow for modern mining enterprises are considered, taking into account the technical and technological factors that characterize the method of extracting the material. The results of the work are of theoretical and practical interest for building transport conveyor models, considering the stochastic nature of the input material flow, and can be used to improve the efficiency of algorithms for optimal control of the transport conveyor material flow.
Multicriterion Synthesis of Intelligent Control Systems of Generating Unit of Nuclear Power Station
(Iran University of Science & Technology, 2014) Jafari Henjani, Seyed Mojtaba; Severin, Valeriy Petrovich
The paper is devoted to solution of some problems in nuclear power station generating unit intellectual control systems using genetic algorithms on the basis of control system model development, optimizations methods of their direct quality indices and improved integral quadratic estimates. Some mathematical vector models were obtained for control system multicriterion quality indices with due consideration of stability and quality indices criteria, this increasing the reliability of optimal control system synthesis. Optimal control systems with fuzzy controllers were synthesized for nuclear reactor, steam generator and steam turbine, thus allowing comparison between fuzzy controllers and traditional PID controllers. Mathematical models built for nuclear power station generating unit control systems, including nuclear reactor, steam generator, steam turbine and their control systems interacting under normal operational modes, which permitted to perform parametrical synthesis of system and to study various power unit control laws. On the basis of power unit control system models controllers were synthesized for normal operational modes.
Optimal design of intelligent control systems of steam turbine using genetic algorithms
(Institute of Information Theories and Applications FOI ITHEA, 2009) Fedyanyna, Khrystyna; Kucher, Ievgeniia; Severin, Valeriy Petrovich
One of the basic engineering problems of the automatic control systems synthesis for steam turbines is systems quality indices optimization task. The features of such task are defined by plenty of control systems structural parameters, complication of quality indices formalization and calculation, the systems models high order. The greatest difficulty of the control system synthesis is optimization models and methods design. The paper purpose is to develop models and methods for optimum design of the intelligent automatic control systems of atomic power station steam turbine using genetic algorithms. The steam turbine automatic control system is applied to stabilize turbine rotor frequency with high precision. The intelligent steam turbine control system includes a steam turbine, frequency sensor, intelligent frequency regulator, electro-hydraulic automatic drive and turbine adjusting valve. Input signals on an automatic drive can be given by the steam pressure regulator through the turbine management mechanism or by the electric power regulator. Assumptions substantiated to model the automatic control system and automatic drive as executive link of control system. The automatic drive diagram of principle includes electro-hydraulic transformer, sleeve valve, servomotor, position sensors and electronic part. In the paper were built the mathematical models of automatic drive and steam turbine, the models permanent parameters values were calculated, the mathematical models of the automatic control system were developed in state space with the intelligent frequency regulator, the regulator parameters were optimized with system quality indices using genetic algorithms.
Optimal synthesis of intelligent control systems of atomic power station using genetic algorithms
(Institute of Information Theories and Applications FOI ITHEA, 2009) Jafari Henjani, Seyed Mojtaba; Severin, Valeriy Petrovich
The paper is devoted to the development of a perspective concept of atomic station power block intelligent automatic control systems synthesis on the basis of mathematical models and numeric methods of vector optimization of systems quality indexes using genetic algorithms. The methods for calculation of direct quality indexes and improved integral quadratic estimates have been created. The step-by-step principle of transition to the domain of system stability has been based. There have also been suggested vector objective functions including stability conditions and taking into consideration quality indexes priorities. The reliable genetic algorithms for vector objective functions optimization have been suggested. Mathematical models in the state space for intelligent automatic control systems of nuclear reactor and steam generator have been worked out. The quality indexes optimization of power block intelligent control systems has been carried out, which allowed to estimate various controller types efficiency.
Optimization of direct quality indexes of automatic control systems of steam generator productivity
(НТУ "ХПІ", 2018) Nikulina, Elena Nikolaevna; Severyn, Valerii Petrovich; Kotsiuba, Nina Viktorivna
The system of automatic control of the productivity of the PGV-1000 steam generator of the power unit of the nuclear power plant with the WWER-1000 reactor is considered. This control system includes a system for automatically controlling the water level in the steam generator. The error signal, which is fed to the input of the productivity controller, is generated by the signal of the specified speed of the drive turbine, as well as pulses from the thermal power sensor and from the water and vapor pressure sensors. Based on the model of the water level control system in the steam generator, mathematical models of performance control systems have been developed under various control laws. To formulate optimization tasks for performance management systems, vectors from variable parameters of performance controllers are formed, constraints on these parameters are imposed, constraints are created for the areas of system stability, direct indexes of system quality are introduced, and a vector objective function is created that takes into account all imposed restrictions and quality criteria. Computational experiments on optimizing the controllers of productivity control systems were performed on the basis of direct quality indexes of systems by modified methods of step adaptation and Nelder – Mead. Analysis of the results of optimization of performance control systems allows us to conclude that, in comparison with the minimization of integral quadratic estimates, the optimization of direct quality indexes has made it possible to substantially improve the speed of the systems. The greatest value of the control time takes place for the differential controller, and the smallest identical values – for the proportional-integral and proportional-integral-differential regulators. Theoretically, the expediency of using a more simple proportional-integral controller in the steam generator productivity control system is justified. Additional analysis of the state variables in the productivity control system and comparison of transients before and after optimization allows us to conclude that the maximum deviation of the water level in the steam generator has decreased and its oscillations have disappeared. Also, fluctuations in water flow disappeared, the maximum deviation and oscillation of the control error decreas ed substantially, the overshoot and oscillations of other state variables practically disappeared. Thus, the optimization of the quality indexes of the automatic control system of the steam generator’s productivity has made it possible to significantly improve the main processes in it.
Parametric synthesis of control systems for the steam generator of a nuclear power plan
(Технологічний центр, Українська державна академія залізничного транспорту, 2022) Nikulina, Elena Nikolaevna; Severin, Valeriy Petrovich; Kotsiuba, Nina Viktorivna
This paper proposes models and methods of the parametric synthesis of automatic control systems for a steam generator at a nuclear power plant, based on the modification of unconditional optimization methods. A mathematical model of steam generator control systems designed for the synthesis of model parameters has been considered. Algorithms are given for calculating level objective functions that take into consideration the limitations of variable parameters and quality indicators of problems for identifying and optimizing model parameters. The methods of unconditional optimization have been modified by introducing the operation of comparing the values of the level objective functions. Using the information technology of optimization, computational experiments were carried out to synthesize the parameters of the steam generator control systems by optimizing the level objective functions. The values of 54 parameters for the model of the control system in the PGV-1000 steam generator were identified, the value of standard deviation in the processes of 1 % from the experimental processes was achieved in the model. The result of parametric synthesis of optimal control systems for a steam generator produced a minimum control time of 131 seconds while the time of computational experiments did not exceed 10 minutes. The peculiarity of the proposed approach to the parametric synthesis of control system models is that the level objective function as a single mathematical object includes all the information about the synthesis problem. Therefore, a given approach is promising for simplifying software for solving complex problems of parametric synthesis of control systems. The considered technology of parametric synthesis of control systems could increase the degree of scientific validity of technical projects to improve various applied and promising control systems.

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