Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.61-66
K. Latyshev, K. Pryakhina, O. Zbyrannyk
Purpose is to study the problem of efficiency of electrical enterprises by conducting a marketing analysis of the market of electrical products. Methodology. A set of theoretical and empirical methods of scientific cognition was used to solve the set tasks: analysis and transformation, diagnostic, deduction and analogy, statistical methods of comparative analysis, synthesis, graphic image. The information and empirical base is the data of the State Statistics Service of Ukraine, reports of the leading enterprises of Ukraine, materials of monographic researches of domestic and foreign scientists, Internet resources. Findings. The dynamics of the output of electrical products in 2018 shows that there is a slow growth in the production of electrical products, and the level of production in 2016 is not even 50% reached. The most needed in the market of electrical products are products for electricity consumption, which is important for the study of the marketing environment. The domestic market of lighting products shows a growing trend, in 2018 sold LED products worth 123 million euros, which was 47% of total production of lighting products. The economic crisis has somewhat destabilized the lighting market and reduced the growth rate of sales, but did not significantly affect the market of LED light sources. Originality. The modern domestic lighting market is focused on innovative products and energy-saving technologies, which in the structure of lighting sources occupy 75% of total sales. In the forecast period (2021–2023), the predominance of energy-saving technologies in the structure of sales will be observed, which is due to a significant rise in energy prices. Practical value. The study will allow domestic manu- facturers of lighting products in order to maintain their own position in the market, it is necessary to take active meas- ures to form and improve their own image. Сonclusions. The key potential opportunities for lighting companies are: the formation of mutually beneficial partnerships and business relationships in domestic and international markets through the formation of integration associations, which will form a strategy of attractive prices; opportunity to expand the range of products and services on the market, intensify marketing activities, improve the quality of management, use resources more efficiently, compete successfully with foreign companies.
{"title":"MARKETING ANALYSIS OF THE MARKET FOR ELECTRICAL ENGINEERING PRODUCTS","authors":"K. Latyshev, K. Pryakhina, O. Zbyrannyk","doi":"10.30929/1995-0519.2021.4.61-66","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.61-66","url":null,"abstract":"Purpose is to study the problem of efficiency of electrical enterprises by conducting a marketing analysis of the market of electrical products. Methodology. A set of theoretical and empirical methods of scientific cognition was used to solve the set tasks: analysis and transformation, diagnostic, deduction and analogy, statistical methods of comparative analysis, synthesis, graphic image. The information and empirical base is the data of the State Statistics Service of Ukraine, reports of the leading enterprises of Ukraine, materials of monographic researches of domestic and foreign scientists, Internet resources. Findings. The dynamics of the output of electrical products in 2018 shows that there is a slow growth in the production of electrical products, and the level of production in 2016 is not even 50% reached. The most needed in the market of electrical products are products for electricity consumption, which is important for the study of the marketing environment. The domestic market of lighting products shows a growing trend, in 2018 sold LED products worth 123 million euros, which was 47% of total production of lighting products. The economic crisis has somewhat destabilized the lighting market and reduced the growth rate of sales, but did not significantly affect the market of LED light sources. Originality. The modern domestic lighting market is focused on innovative products and energy-saving technologies, which in the structure of lighting sources occupy 75% of total sales. In the forecast period (2021–2023), the predominance of energy-saving technologies in the structure of sales will be observed, which is due to a significant rise in energy prices. Practical value. The study will allow domestic manu- facturers of lighting products in order to maintain their own position in the market, it is necessary to take active meas- ures to form and improve their own image. Сonclusions. The key potential opportunities for lighting companies are: the formation of mutually beneficial partnerships and business relationships in domestic and international markets through the formation of integration associations, which will form a strategy of attractive prices; opportunity to expand the range of products and services on the market, intensify marketing activities, improve the quality of management, use resources more efficiently, compete successfully with foreign companies.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127655590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.110-115
L. Davydenko, V. Davydenko, N. Davydenko, Serhiy Kunytskyi
Purpose. Development of a mechanism identification of changes in the actual operation conditions of the water supply facility depending on the season. Methodology. Methods of intellectual analysis of profiles of mode indicators were used to identify regularities in the formation of the operation mode of the facility. The mathematical apparatus of pattern recognition algorithm with training was used to classify the profiles of mode indicators. Methods of self-organization of models of complex systems were used for structural and parametric identification of the classifier model. Results. The necessity of the analysis of the characteristics of operation mode of the pumping station of water supply, obtained from the monitoring system, to identify regularities in the formation of water supply was substantiated. The daily graph of water consumption from the water supply network was used as a mode indicator of the water supply process. Indicators of water supply volumes and graph unevenness were used to describe the water supply graph. The expediency of application of self-organization methods for solving the problem of classification and construction of the classifier model was substantiated. Structural and parametric identification of the classifier model for daily water consumption graphs was performed using GMDH Neural Networks. The search for the optimal model was performed in three classes of neural networks. Better neural network structure was chosen on the basis of criterion of regularity. The K-block cross-validation strategy was used to test the models. The results of the verification of the classifier model showed the high quality of the classification. Originality. A method for identifying changes in the operation conditions of the water supply facility due to the influence of seasonal factors, based on the usage of the classifier of profiles of daily water consumption graphs from the water supply network, was proposed. Practical value. The constructed model of the classifier allows defining of belonging of a profile of the daily water consumption graph, received from monitoring system of the water supply mode, to one of typical classes. The fact of class change indicates a change in the actual operation conditions of the water supply facility. Conclusions. Analysis of daily graphs of water consumption using the pattern recognition algorithm makes it possible to establish the change in the actual operation conditions of the water supply facility caused by the influence of seasonal factors. The usage of neural networks of GMDH makes it possible to perform automatically structural and parametric identification of the classifier model. Application of the offered principles is a basis of effective planning of operation modes of pumping station of water supply. References 16, tables 3.
{"title":"APPLICATION OF GMDH NEURAL NETWORKS TO DETECT CHANGES IN THE OPERATION CONDITIONS OF THE WATER SUPPLY PUMPING STATION CAUSED BY THE INFLUENCE OF SEASONAL FACTORS","authors":"L. Davydenko, V. Davydenko, N. Davydenko, Serhiy Kunytskyi","doi":"10.30929/1995-0519.2021.4.110-115","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.110-115","url":null,"abstract":"Purpose. Development of a mechanism identification of changes in the actual operation conditions of the water supply facility depending on the season. Methodology. Methods of intellectual analysis of profiles of mode indicators were used to identify regularities in the formation of the operation mode of the facility. The mathematical apparatus of pattern recognition algorithm with training was used to classify the profiles of mode indicators. Methods of self-organization of models of complex systems were used for structural and parametric identification of the classifier model. Results. The necessity of the analysis of the characteristics of operation mode of the pumping station of water supply, obtained from the monitoring system, to identify regularities in the formation of water supply was substantiated. The daily graph of water consumption from the water supply network was used as a mode indicator of the water supply process. Indicators of water supply volumes and graph unevenness were used to describe the water supply graph. The expediency of application of self-organization methods for solving the problem of classification and construction of the classifier model was substantiated. Structural and parametric identification of the classifier model for daily water consumption graphs was performed using GMDH Neural Networks. The search for the optimal model was performed in three classes of neural networks. Better neural network structure was chosen on the basis of criterion of regularity. The K-block cross-validation strategy was used to test the models. The results of the verification of the classifier model showed the high quality of the classification. Originality. A method for identifying changes in the operation conditions of the water supply facility due to the influence of seasonal factors, based on the usage of the classifier of profiles of daily water consumption graphs from the water supply network, was proposed. Practical value. The constructed model of the classifier allows defining of belonging of a profile of the daily water consumption graph, received from monitoring system of the water supply mode, to one of typical classes. The fact of class change indicates a change in the actual operation conditions of the water supply facility. Conclusions. Analysis of daily graphs of water consumption using the pattern recognition algorithm makes it possible to establish the change in the actual operation conditions of the water supply facility caused by the influence of seasonal factors. The usage of neural networks of GMDH makes it possible to perform automatically structural and parametric identification of the classifier model. Application of the offered principles is a basis of effective planning of operation modes of pumping station of water supply. References 16, tables 3.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122654231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.124-134
Andrii Havrushkevych, Volodymyr Geichuk, Nataliia Havrushkevych, Olexander Kravets, A. Romashko
Purpose. The purpose of these studies is to develop a method designing rotor heads for finishing cylindrical parts with evenly spaced elements on the periphery and approbation a technique at development a design a rotor head for realization magnetic-abrasive processing cylindrical gear wheels over a ring bath. Methodology.The design technique is based on the synthesis of structural-kinematic schemes and structural formulas of rotary machine composing.In the synthesis process are analyzed the possible general coordinate transformations matrices of the forming system of the rotor heads.The general matrix coordinate transformations is selected by the results of a comprehensive assessment the criteria of the intensity of magnetic abrasive treatment and the shape of the edge. Findings.The design technique is rep- resented by an algorithm that includes the stages of synthesis structural-kinematic schemes and structural formulas of the composing rotary machines and the stage for determining their basic design parameters and dimensions. Originality.The algorithm of development structural-kinematic schemes and structural formulas arrangement rotary machines for magnetic-abrasive processing blanks in the stage of definition and choice of rational modes is im- proved.This allows you to get theparticular level of quality of processing that is best for the whole set of machined sur- faces and edges of the work pieces. Practicalvalue.The design technique has been tested in the design and construction of the rotor head for magnetic-abrasive processing gears over the ring bath. The design of the magnetic system with a double-circuit magnetic circuit is developed, which allows to increase the width of the working zone up to 150 mm, and the outer diameter of the processed gears up to 400 mm. Conclusions. As a result of the carried out researches the tech- nique and recommendations on designing of rotor heads for finishing of cylindrical details with equally located ele- ments on periphery(gears, end and axial cutting tools, etc.) are developed.To increase the efficiency of the technique, it is necessary to conduct additional studies of tribotechnical properties of magnetic-abrasive tools with a wider coverage of fractions of particles and processed materials and especially experimental studies of resistance forces during the movement of bodies in the working environment.
{"title":"METHOD OF DESIGNING ROTOR HEADS FOR FINISHING CYLINDRICAL PARTS WITH UNIFORMLY LOCATED ELEMENTS ON THE PERIPHERAL","authors":"Andrii Havrushkevych, Volodymyr Geichuk, Nataliia Havrushkevych, Olexander Kravets, A. Romashko","doi":"10.30929/1995-0519.2021.4.124-134","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.124-134","url":null,"abstract":"Purpose. The purpose of these studies is to develop a method designing rotor heads for finishing cylindrical parts with evenly spaced elements on the periphery and approbation a technique at development a design a rotor head for realization magnetic-abrasive processing cylindrical gear wheels over a ring bath. Methodology.The design technique is based on the synthesis of structural-kinematic schemes and structural formulas of rotary machine composing.In the synthesis process are analyzed the possible general coordinate transformations matrices of the forming system of the rotor heads.The general matrix coordinate transformations is selected by the results of a comprehensive assessment the criteria of the intensity of magnetic abrasive treatment and the shape of the edge. Findings.The design technique is rep- resented by an algorithm that includes the stages of synthesis structural-kinematic schemes and structural formulas of the composing rotary machines and the stage for determining their basic design parameters and dimensions. Originality.The algorithm of development structural-kinematic schemes and structural formulas arrangement rotary machines for magnetic-abrasive processing blanks in the stage of definition and choice of rational modes is im- proved.This allows you to get theparticular level of quality of processing that is best for the whole set of machined sur- faces and edges of the work pieces. Practicalvalue.The design technique has been tested in the design and construction of the rotor head for magnetic-abrasive processing gears over the ring bath. The design of the magnetic system with a double-circuit magnetic circuit is developed, which allows to increase the width of the working zone up to 150 mm, and the outer diameter of the processed gears up to 400 mm. Conclusions. As a result of the carried out researches the tech- nique and recommendations on designing of rotor heads for finishing of cylindrical details with equally located ele- ments on periphery(gears, end and axial cutting tools, etc.) are developed.To increase the efficiency of the technique, it is necessary to conduct additional studies of tribotechnical properties of magnetic-abrasive tools with a wider coverage of fractions of particles and processed materials and especially experimental studies of resistance forces during the movement of bodies in the working environment.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127411056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.47-54
K. Osadcha, V. Osadchyi, V. Kruglyk, O. Spirin
Purpose: Аnalysis and generalization of ways of adaptation of the educational content of electronic courses to the mobile format; selection and testing of the optimal option based on the existing infrastructure of the higher education institution on the basis of the Moodle platform. Methodology: The method of analysis, systematization, generalization, comparison and synthesis is used in the article; generalization and systematization of own practical experience, interpre- tation of research results and pedagogical observation of the results of the educational process. Findings: The prolifera- tion of mobile devices expands the possibilities of their application in the educational process of training professionals to be. For the implementation of distance and blended learning in mobile learning the adaptation of e-learning courses to the mobile format is required. To do this, itis important to pay attention to the factors that cause compliance with the requirements for pedagogical design of e-courses on mobile devices, namely: the small screen size, the lack of mouse, the need for constant support and the presence of distractions. Originality: Considering the predominant use of the Moodle platform by higher education institutions in Ukraine and the fact that much work has been done by teachers to create distance learning courses in this system, it is advisable to consider the possibility of working with Moodle on mobile and portable devices. In particular, one of the main conditions that contributes to the multiplatform nature of e- courses is the use of the site design theme for the distance learning, which is adapted for different types of devices. Practical value: The e-courses in the mobile format in the browser and in the mobile application are different. The first one is very similar in appearance to a personal computer browser view. This option will be convenient for those stu- dents who are accustomed to designing a site on a personal computer and find it difficult to switch to another interface. However, the interface of the mobile application is more convenient to use in the format of mobile learning, because it takes into account all the requirements for an e-course in the mobile format (convenient and clear navigation, simple and usable design, clear division into information blocks, etc.). Conclusions: The Moodle mobile application allows users to adapt e-learning courses to the mobile format in the easiest way: by taking into account the requirements for pedagogical design of mobile learning applications, the teacher only has to place and compose learning materials con- forming the requirements to font, text, graphics and video structuring.
{"title":"ADAPTATION OF E-LEARNING COURSES TO THE MOBILE FORMATFOR BLENDED LEARNING","authors":"K. Osadcha, V. Osadchyi, V. Kruglyk, O. Spirin","doi":"10.30929/1995-0519.2021.4.47-54","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.47-54","url":null,"abstract":"Purpose: Аnalysis and generalization of ways of adaptation of the educational content of electronic courses to the mobile format; selection and testing of the optimal option based on the existing infrastructure of the higher education institution on the basis of the Moodle platform. Methodology: The method of analysis, systematization, generalization, comparison and synthesis is used in the article; generalization and systematization of own practical experience, interpre- tation of research results and pedagogical observation of the results of the educational process. Findings: The prolifera- tion of mobile devices expands the possibilities of their application in the educational process of training professionals to be. For the implementation of distance and blended learning in mobile learning the adaptation of e-learning courses to the mobile format is required. To do this, itis important to pay attention to the factors that cause compliance with the requirements for pedagogical design of e-courses on mobile devices, namely: the small screen size, the lack of mouse, the need for constant support and the presence of distractions. Originality: Considering the predominant use of the Moodle platform by higher education institutions in Ukraine and the fact that much work has been done by teachers to create distance learning courses in this system, it is advisable to consider the possibility of working with Moodle on mobile and portable devices. In particular, one of the main conditions that contributes to the multiplatform nature of e- courses is the use of the site design theme for the distance learning, which is adapted for different types of devices. Practical value: The e-courses in the mobile format in the browser and in the mobile application are different. The first one is very similar in appearance to a personal computer browser view. This option will be convenient for those stu- dents who are accustomed to designing a site on a personal computer and find it difficult to switch to another interface. However, the interface of the mobile application is more convenient to use in the format of mobile learning, because it takes into account all the requirements for an e-course in the mobile format (convenient and clear navigation, simple and usable design, clear division into information blocks, etc.). Conclusions: The Moodle mobile application allows users to adapt e-learning courses to the mobile format in the easiest way: by taking into account the requirements for pedagogical design of mobile learning applications, the teacher only has to place and compose learning materials con- forming the requirements to font, text, graphics and video structuring.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131144475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.169-176
S. Serhiienko, Evgeniya Burdilna, O. Klyuyev
Purpose. The article explored options for control systems for the electric drive of grain-metal machine conveyor to stabilize the speed of conveyor belt when the load changes. Methodology. A control system is proposed that implements the principles of subordinate regulation and is supplemented by compensatory feedbacks in the control channels of active and reactive energy. The calculation of the regulators and the modeling of the system operation have been completed. The analysis of the obtained characteristics showed that the synthesized system is characterized by good quality indicators. However, the characteristics were obtained for the case of known parameters of an asynchronous machine and adjusting the regulators for these parameters. Studies have shown that for the proposed structure, the most significant is the incorrect determination of the inductive reactances of the stator and rotor of asynchronous machine. So, when the inductance de- viates by 30%, significant fluctuations occur in the subordinate regulation system. Complex solution to the problem of providing low sensitivity to parametric and coordinate disturbances and an increase in dynamic and static accuracy can be obtained in a class of systems, that are stable with an unlimited increase in the gain, as a solution to the problem of ana- lytical design of optimal regulators based on the modified symmetry principle. The regulators of the reactive energy transmission channel with series-parallel correction, which are modified PID structures, have been synthesized. Regulators with sequential correction with PID and PIDD2 structures are synthesized for the active energy transmission channel. Results. Analysis of the obtained results of characteristics showed, that the optimal control system is characterized by better quality indicators in comparison with the classical system of subordinate regulation and practically insensitive to changes in the parameters of the electric drive. Originality. The results of mathematical modeling confirmed the possi- bility of using control systems synthesized as a solution to the problem of analytical design of optimal controllers based on the modified symmetry principle, to improve the quality indicators of the AC electric drive of the grain thrower con- veyor. Practical value. The use of the proposed optimal control system will provide the possibility of stabilizing the speed of the conveyor belt of the grain thrower, which will reduce the percentage of injured and damaged grain. References 16. Figures 14.
{"title":"VARIABLE FREQUENCY DRIVE OF GRAIN MACHINE CONVEYOR WITH IMPROVED QUALITY INDICATORS","authors":"S. Serhiienko, Evgeniya Burdilna, O. Klyuyev","doi":"10.30929/1995-0519.2021.4.169-176","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.169-176","url":null,"abstract":"Purpose. The article explored options for control systems for the electric drive of grain-metal machine conveyor to stabilize the speed of conveyor belt when the load changes. Methodology. A control system is proposed that implements the principles of subordinate regulation and is supplemented by compensatory feedbacks in the control channels of active and reactive energy. The calculation of the regulators and the modeling of the system operation have been completed. The analysis of the obtained characteristics showed that the synthesized system is characterized by good quality indicators. However, the characteristics were obtained for the case of known parameters of an asynchronous machine and adjusting the regulators for these parameters. Studies have shown that for the proposed structure, the most significant is the incorrect determination of the inductive reactances of the stator and rotor of asynchronous machine. So, when the inductance de- viates by 30%, significant fluctuations occur in the subordinate regulation system. Complex solution to the problem of providing low sensitivity to parametric and coordinate disturbances and an increase in dynamic and static accuracy can be obtained in a class of systems, that are stable with an unlimited increase in the gain, as a solution to the problem of ana- lytical design of optimal regulators based on the modified symmetry principle. The regulators of the reactive energy transmission channel with series-parallel correction, which are modified PID structures, have been synthesized. Regulators with sequential correction with PID and PIDD2 structures are synthesized for the active energy transmission channel. Results. Analysis of the obtained results of characteristics showed, that the optimal control system is characterized by better quality indicators in comparison with the classical system of subordinate regulation and practically insensitive to changes in the parameters of the electric drive. Originality. The results of mathematical modeling confirmed the possi- bility of using control systems synthesized as a solution to the problem of analytical design of optimal controllers based on the modified symmetry principle, to improve the quality indicators of the AC electric drive of the grain thrower con- veyor. Practical value. The use of the proposed optimal control system will provide the possibility of stabilizing the speed of the conveyor belt of the grain thrower, which will reduce the percentage of injured and damaged grain. References 16. Figures 14.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122299443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.116-123
K. Trapezon, A. Trapezon
Purpose. The aim of the work is to construct a closed analytical solution of the problem of natural vibrations of the beam, the width of which varies according to the law exp (αx2). Methodology. The approach is based on the provisions of symmetric analysis of differential equations with variable coefficients. This approach allows you to find a way to obtain an analytical solution of the corresponding differential equation and, ultimately, the boundary value problem. Findings. The main result is the construction of the algorithm and obtaining the solution of the differential equation of the IV order, which describes the transverse bending vibrations of the beam with a special law of change of width (the thickness of the beam is a constant value). Two examples of the analysis of oscillations of such beam in case of its bilateral rigid fastening and cantilever fastening are resulted. For these cases, the frequency equations are obtained, the natural frequencies and amplitude coefficients are found, which are necessary for the construction of natural forms of oscillations. Originality.The approach presented in this paper is based on the idea of symmetries of differential equations and is characterized by a sim- plified analysis of the solution of the problem of bending oscillations of the beam with a special law of width. The method proposed for solving the boundary value problem is convenient and simple, because the results are found without the use of numerical research methods. Practical value.Examples of the exact analysis of fluctuations which allow to assert about real possibility of expansion of an existing number of configurations of a beam, both on width, and on ways of fastening are resulted. Such beams can, for example, be used as prototype samples for resonant tests of materials for fatigue strength. Сonclusions. The given algorithm for constructing the solution of the problem on eigenvalues for a beam with the given special law of change of width is universal and can be extended to other constructions of beams. Since in this case the question arises only about the choice of the approximation function, which allows to use the method of symmetries and obtain an exact solution of the corresponding differential equation of the IV order, which in turn describes the transverse oscillations of the beams.
{"title":"NATURAL BENDING VIBRATIONS OF THE BEAM WITH THE SPECIAL LAW OF CHANGE OF WIDTH","authors":"K. Trapezon, A. Trapezon","doi":"10.30929/1995-0519.2021.4.116-123","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.116-123","url":null,"abstract":"Purpose. The aim of the work is to construct a closed analytical solution of the problem of natural vibrations of the beam, the width of which varies according to the law exp (αx2). Methodology. The approach is based on the provisions of symmetric analysis of differential equations with variable coefficients. This approach allows you to find a way to obtain an analytical solution of the corresponding differential equation and, ultimately, the boundary value problem. Findings. The main result is the construction of the algorithm and obtaining the solution of the differential equation of the IV order, which describes the transverse bending vibrations of the beam with a special law of change of width (the thickness of the beam is a constant value). Two examples of the analysis of oscillations of such beam in case of its bilateral rigid fastening and cantilever fastening are resulted. For these cases, the frequency equations are obtained, the natural frequencies and amplitude coefficients are found, which are necessary for the construction of natural forms of oscillations. Originality.The approach presented in this paper is based on the idea of symmetries of differential equations and is characterized by a sim- plified analysis of the solution of the problem of bending oscillations of the beam with a special law of width. The method proposed for solving the boundary value problem is convenient and simple, because the results are found without the use of numerical research methods. Practical value.Examples of the exact analysis of fluctuations which allow to assert about real possibility of expansion of an existing number of configurations of a beam, both on width, and on ways of fastening are resulted. Such beams can, for example, be used as prototype samples for resonant tests of materials for fatigue strength. Сonclusions. The given algorithm for constructing the solution of the problem on eigenvalues for a beam with the given special law of change of width is universal and can be extended to other constructions of beams. Since in this case the question arises only about the choice of the approximation function, which allows to use the method of symmetries and obtain an exact solution of the corresponding differential equation of the IV order, which in turn describes the transverse oscillations of the beams.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124291930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.149-156
O. Yandulskyi, V. Mossakovskyi
Purpose. Research of the position changing of the hot-spot point of the oil-immersed power transformers using simulation. Methodology. The theory and practice of calculation of power transformers, standardized mathematical models of calculation of the hot-spot point temperature and the mathematical modeling were used. Results. At Figures 4 - 6 under the number 1 indicate the initial conditions, namely the rated load of the transformer; eddy loses at rated load and 20 ° C ambient temperature. Under initial conditions, the hot-spot point is located on the surface of the low voltage winding at the middle leg. Ambient temperature changing and correction of eddy losses to the load factor of the each phase, numbers 2 - 4, cause the movement of the hot-spot point on the surface of this winding. The main factor that causes the movement of the hot-spot point is the load factor of each phase, numbers 3 or 4 and 5 or 6. If there is an overload of some phase, then the hot-spot point will be on the surface of the low voltage winding of this overloaded phase. Originality. According to the information obtained from [1-4] it is seen that the movement of the hot-spot point is not paid attention at all. For example, in [2] the position of this point is considered unchanged and already known. The results obtained from the research have shown that this provision is not true. Practical value. The obtained results is seen in the possibility of providing recommendations for paying additional attention to monitoring the insulation of windings at a certain point during the current maintenance or post-accident inspection of the transformer. Tracking data of the position of the hottest point should be stored, especially if the overheating in this point take place. Conclusions. The research was performed on transformers S13-MRL-40, S13-MRL-160 and S13-MRL-1000 with primary voltage evel 10 kV. The fact of movement of the hot-spot point on the insulation surface of the windings of these transformers under different operating conditions is established and demonstrated. Six operating conditions were considered. As can be seen from Figures 4 – 6, the hot-spot point responds to a change in operating conditions by changing its position. In case of the change in ambient temperature or eddy loss the point moves on the surface of the winding within a single phase. In case of the change in load losses, the point can move between phases. The movement of the point between the phases takes place under the load asymmetry.
{"title":"MODELLING OF THE POWER TRANSFORMERS TO THE DETERMINATION OF THE HOT-SPOT POINT POSITION UNDER THE DIFFERENT OPERATING CONDITIONS","authors":"O. Yandulskyi, V. Mossakovskyi","doi":"10.30929/1995-0519.2021.4.149-156","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.149-156","url":null,"abstract":"Purpose. Research of the position changing of the hot-spot point of the oil-immersed power transformers using simulation. Methodology. The theory and practice of calculation of power transformers, standardized mathematical models of calculation of the hot-spot point temperature and the mathematical modeling were used. Results. At Figures 4 - 6 under the number 1 indicate the initial conditions, namely the rated load of the transformer; eddy loses at rated load and 20 ° C ambient temperature. Under initial conditions, the hot-spot point is located on the surface of the low voltage winding at the middle leg. Ambient temperature changing and correction of eddy losses to the load factor of the each phase, numbers 2 - 4, cause the movement of the hot-spot point on the surface of this winding. The main factor that causes the movement of the hot-spot point is the load factor of each phase, numbers 3 or 4 and 5 or 6. If there is an overload of some phase, then the hot-spot point will be on the surface of the low voltage winding of this overloaded phase. Originality. According to the information obtained from [1-4] it is seen that the movement of the hot-spot point is not paid attention at all. For example, in [2] the position of this point is considered unchanged and already known. The results obtained from the research have shown that this provision is not true. Practical value. The obtained results is seen in the possibility of providing recommendations for paying additional attention to monitoring the insulation of windings at a certain point during the current maintenance or post-accident inspection of the transformer. Tracking data of the position of the hottest point should be stored, especially if the overheating in this point take place. Conclusions. The research was performed on transformers S13-MRL-40, S13-MRL-160 and S13-MRL-1000 with primary voltage evel 10 kV. The fact of movement of the hot-spot point on the insulation surface of the windings of these transformers under different operating conditions is established and demonstrated. Six operating conditions were considered. As can be seen from Figures 4 – 6, the hot-spot point responds to a change in operating conditions by changing its position. In case of the change in ambient temperature or eddy loss the point moves on the surface of the winding within a single phase. In case of the change in load losses, the point can move between phases. The movement of the point between the phases takes place under the load asymmetry.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123056997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.11-16
Alina Dmytryk
Purpose. The article deals with the problem of low motivation to study English during e-learning. The author works with such phenomena as «distance education», «warm up activity», «motivation» and links between them. The purpose of this research is to define the notion of warm up activities as an effective way to motivate students to learn foreign language during distance learning. Methodology. The scientific methods of theoretical and system analysis of psycho- logical and pedagogical literature, comparison, systematization, description, generalization, practical experience, inter- pretation of research results and pedagogical observation of the results of the educational process, have been used in order to define warm-ups as one of the ways to motivate students to learn English during distance education. Findings. Analysis of scientific works and practical observation revealed that the motivation to study is influenced by the emo- tional factor of the students, so in order to interest them, teachers are required to use up-to-date information and com- munication technologies, to include materials in various formats to meet the needs of students. So, it has been estab- lished that warm ups have a significant impact on the cognitive activity of students. Originality. Since distance learning is gaining more and more popularity around the world, this phenomenon is quite new in Ukraine. University teachers are faced with new challenges so the issue of engaging students to learn English during e-learning is relevant nowadays. This paper has practical advice on how to solve this problem and help teachers of high educational institutions to stimu- late students’ cognitive activity. Practical value. The author suggests a list of web resources for practical use for both teachers and students in distance learning. The selection consists of online platforms for creating quizzes, tests, games and watching videos in order to increase the cognitive activity of students.
{"title":"WARM-UPS AS A WAY TO ENGAGE STUDENTS IN LEARNING ENGLISH DURING DISTANCE EDUCATION","authors":"Alina Dmytryk","doi":"10.30929/1995-0519.2021.4.11-16","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.11-16","url":null,"abstract":"Purpose. The article deals with the problem of low motivation to study English during e-learning. The author works with such phenomena as «distance education», «warm up activity», «motivation» and links between them. The purpose of this research is to define the notion of warm up activities as an effective way to motivate students to learn foreign language during distance learning. Methodology. The scientific methods of theoretical and system analysis of psycho- logical and pedagogical literature, comparison, systematization, description, generalization, practical experience, inter- pretation of research results and pedagogical observation of the results of the educational process, have been used in order to define warm-ups as one of the ways to motivate students to learn English during distance education. Findings. Analysis of scientific works and practical observation revealed that the motivation to study is influenced by the emo- tional factor of the students, so in order to interest them, teachers are required to use up-to-date information and com- munication technologies, to include materials in various formats to meet the needs of students. So, it has been estab- lished that warm ups have a significant impact on the cognitive activity of students. Originality. Since distance learning is gaining more and more popularity around the world, this phenomenon is quite new in Ukraine. University teachers are faced with new challenges so the issue of engaging students to learn English during e-learning is relevant nowadays. This paper has practical advice on how to solve this problem and help teachers of high educational institutions to stimu- late students’ cognitive activity. Practical value. The author suggests a list of web resources for practical use for both teachers and students in distance learning. The selection consists of online platforms for creating quizzes, tests, games and watching videos in order to increase the cognitive activity of students.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128221716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-23DOI: 10.30929/1995-0519.2021.4.157-162
Y. Trotsenko, Artem Nesterko, V. Chyzhevskyi, M. Dixit
Purpose. The results of studying the voltage drop in the inductive ractance of the connecting wires of surge arresters installed in open switchgear are presented. Methodology. Free software for circuit simulation was used to solve electri- cal circuits with nonlinear parameters. To take into account the differences between the negative and positive lightning current impulses, the oscillograms of real lightning currents were digitized using free specialized software. Results. The duration of the impulse front (as well as the total impulse duration) of the positive lightning significantly exceeds the corresponding parameters of the negative lightning current, so the charge carried by the positive lightning significantly exceeds the charge carried by the negative lightning. For these reasons, positive lightning, although less common than ЕЛЕКТРОЕНЕРГЕТИКА, ЕЛЕКТРОТЕХНІКА ТА ЕЛЕКТРОМЕХАНІКА Вісник КрНУ імені Михайла Остроградського. Випуск 4/2021 (129) 162 negative lightning, is more dangerous. It is found that due to the slower front of the impulse, the voltage drop in induc- tive reactance of connecting wires of the surge arresters in the case of positive lightning in 8-11 times less than in the case of negative lightning. Analytical formulas for calculating the inductance of the connecting wires, which take into account the geometric dimensions of the wires, provide more accurate results than the average inductance value of 1.3 μH/m given in the literature. Originality. The approach takes into account the differences between impulses of light- ning currents of negative and positive polarity, which cannot be achieved with use of the approximation of lightning currents by simplified mathematical expressions. Practical value. It is found that voltage drops in the inductive reac- tance will be more dangerous in case of long wire lengths and negative lightning current impulses with a steep front. Conclusions. Further development of the proposed approach is seen in its use for the analysis of circuits for protection of electrical equipment of high-voltage electrical networks from lightning overvoltages using surge arresters. Refer- ences 15, figures 10.
{"title":"ESTIMATION OF VOLTAGE DROP IN INDUCTIVE REACTANCE OF CONNECTING WIRES OF SURGE ARRESTERS","authors":"Y. Trotsenko, Artem Nesterko, V. Chyzhevskyi, M. Dixit","doi":"10.30929/1995-0519.2021.4.157-162","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.4.157-162","url":null,"abstract":"Purpose. The results of studying the voltage drop in the inductive ractance of the connecting wires of surge arresters installed in open switchgear are presented. Methodology. Free software for circuit simulation was used to solve electri- cal circuits with nonlinear parameters. To take into account the differences between the negative and positive lightning current impulses, the oscillograms of real lightning currents were digitized using free specialized software. Results. The duration of the impulse front (as well as the total impulse duration) of the positive lightning significantly exceeds the corresponding parameters of the negative lightning current, so the charge carried by the positive lightning significantly exceeds the charge carried by the negative lightning. For these reasons, positive lightning, although less common than ЕЛЕКТРОЕНЕРГЕТИКА, ЕЛЕКТРОТЕХНІКА ТА ЕЛЕКТРОМЕХАНІКА Вісник КрНУ імені Михайла Остроградського. Випуск 4/2021 (129) 162 negative lightning, is more dangerous. It is found that due to the slower front of the impulse, the voltage drop in induc- tive reactance of connecting wires of the surge arresters in the case of positive lightning in 8-11 times less than in the case of negative lightning. Analytical formulas for calculating the inductance of the connecting wires, which take into account the geometric dimensions of the wires, provide more accurate results than the average inductance value of 1.3 μH/m given in the literature. Originality. The approach takes into account the differences between impulses of light- ning currents of negative and positive polarity, which cannot be achieved with use of the approximation of lightning currents by simplified mathematical expressions. Practical value. It is found that voltage drops in the inductive reac- tance will be more dangerous in case of long wire lengths and negative lightning current impulses with a steep front. Conclusions. Further development of the proposed approach is seen in its use for the analysis of circuits for protection of electrical equipment of high-voltage electrical networks from lightning overvoltages using surge arresters. Refer- ences 15, figures 10.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115310869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-11DOI: 10.30929/1995-0519.2021.3.57-62
I. Shevchenko, D. Vasiliev, N. Rylova, N. Sharonova
Purpose. As a rule modern organizational systems in any industry contain many elements. These elements are connected by a complex scheme of relationships. In the municipal sphere, various programs and projects are implemented simultaneously. To increase the efficiency of work with projects, it is necessary to solve operations management problems. It is necessary to coordinate the allocation of resources, assess the quality of implementation of individual stages of each project, take into account the joint use of contractors, assess risks and eliminate problem situations. The purpose of the research is to improve the conceptual models of decision support systems to create information technology for managing the implementation of many programs and projects in the municipal sphere. Methodology. For the implementation of operational management of many projects, it is advisable to have the appropriate information technology and tools. The development of such technologies requires a certain methodological approach. The difficulties of structural synthesis of executive systems are associated with the uncertainty of the design tasks conditions. It is impossible to fully specify the algorithms of functioning and interaction of executive structures. Results. An improved ontological metamodel of the problem area and an improved model of the decision support system for managing multiple projects have been developed. Originality. The ontological metamodel of the problem area differs in that it has several strata, each of which identifies the relevant problems and aspects of the organization. The model of the decision support system has been improved by adding a formal static description of the implementation process of many projects and their relationship with many attributes and aspects. Practical value. An ontological metamodel allows to establish hierarchical causal relationships between different problems. This is especially true when implementing many projects involving many departments. The model of the decision support system allows making operational decisions taking into account many factors and their interrelations on various aspects of activity. All this contributes to the main task – the development of information technology to support decision-making in the organizational processes of municipal bodies and enterprises. References 12, figures 1.
{"title":"CONCEPTUAL MODELS OF THE DECISION SUPPORT SYSTEM FOR MANAGING SET OF THE MUNICIPAL SPHERE PROJECTS","authors":"I. Shevchenko, D. Vasiliev, N. Rylova, N. Sharonova","doi":"10.30929/1995-0519.2021.3.57-62","DOIUrl":"https://doi.org/10.30929/1995-0519.2021.3.57-62","url":null,"abstract":"Purpose. As a rule modern organizational systems in any industry contain many elements. These elements are connected by a complex scheme of relationships. In the municipal sphere, various programs and projects are implemented simultaneously. To increase the efficiency of work with projects, it is necessary to solve operations management problems. It is necessary to coordinate the allocation of resources, assess the quality of implementation of individual stages of each project, take into account the joint use of contractors, assess risks and eliminate problem situations. The purpose of the research is to improve the conceptual models of decision support systems to create information technology for managing the implementation of many programs and projects in the municipal sphere. Methodology. For the implementation of operational management of many projects, it is advisable to have the appropriate information technology and tools. The development of such technologies requires a certain methodological approach. The difficulties of structural synthesis of executive systems are associated with the uncertainty of the design tasks conditions. It is impossible to fully specify the algorithms of functioning and interaction of executive structures. Results. An improved ontological metamodel of the problem area and an improved model of the decision support system for managing multiple projects have been developed. Originality. The ontological metamodel of the problem area differs in that it has several strata, each of which identifies the relevant problems and aspects of the organization. The model of the decision support system has been improved by adding a formal static description of the implementation process of many projects and their relationship with many attributes and aspects. Practical value. An ontological metamodel allows to establish hierarchical causal relationships between different problems. This is especially true when implementing many projects involving many departments. The model of the decision support system allows making operational decisions taking into account many factors and their interrelations on various aspects of activity. All this contributes to the main task – the development of information technology to support decision-making in the organizational processes of municipal bodies and enterprises. References 12, figures 1.","PeriodicalId":405654,"journal":{"name":"Transactions of Kremenchuk Mykhailo Ostrohradskyi National University","volume":"73 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126615012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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