Systems and Technologies https://st.umsf.in.ua/index.php/journal en-US yuriy.ponch@gmail.com (Поночовний Ю. Л.) vmsu12@gmail.com (Oleg Ivanchenko, Leonid Kabak) Wed, 26 Jun 2024 10:28:27 +0300 OJS 3.1.2.4 http://blogs.law.harvard.edu/tech/rss 60 NEURONETWORK CONTROL OF OFFICE ROOM VENTILATION SYSTEM https://st.umsf.in.ua/index.php/journal/article/view/138 <p>The problem of air quality in enclosed spaces arises due to the operation of heating systems, the use of open fire sources, human respiration, the decomposition of synthetic materials, the ingress of dust from outside, and the presence of microorganisms. Exceeding permissible concentrations can adversely affect human well-being, making air quality control important. Traditional ventilation systems do not account for changing conditions and do not allow flexible air exchange regulation. The creation of modern automated ventilation systems using computational technologies and considering air parameter monitoring results poses a scientific challenge. Modern approaches to managing HVAC systems, which control the quality and comfort of indoor air, maintain air parameters according to sanitary standards, and allow for the creation of closed-loop control systems, have been analyzed. Control systems based on fuzzy logic theory and neural networks have been considered, which allow for effective air parameter management and ensure building energy efficiency. The aim of the article is to develop a neurocontroller for an office ventilation system that provides automated control considering the non-stationary behavior of the object by regulating the compressor motor speed of the ventilation cooling system. The proposed neural network control system uses the principle of inverse neural control for model training and ensures control by minimizing the error function. The neurocontroller is built as a multilayer neural network with sigmoid activation functions. To analyze the effectiveness of the proposed approach, a dataset in the form of time series containing measurements of temperature, humidity, and carbon dioxide concentration was used. Computational experiments with various neural network structures demonstrated the effectiveness of a network with a single hidden layer. It was established that the neurocontroller responds quickly to input signals, and the controlled ventilation system ensures the standard temperature in the room within an acceptable time and without overshoot. Comparison with P-regulator and PID-regulator indicates a significant advantage of the neurocontroller in ensuring control accuracy, response speed, and reducing energy consumption.</p> K. G. Huk Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/138 Wed, 26 Jun 2024 00:00:00 +0300 LIMITED INFINITY https://st.umsf.in.ua/index.php/journal/article/view/139 <p>The paper discusses the identification of the concept of limited infinity, highlighting its relevance in expanding the range of mathematical tools necessary for solving complex applied design tasks in technics. Limited infinity extends the applicability of classical infinity in mathematical problems. The primary objective of the paper is to develop the concept of limited infinity and conduct comprehensive research on it. The paper outlines the fundamental properties of limited infinity, elucidating its key characteristics and practical applications. An analysis of basic mathematical operations involving limited infinity demonstrates that, under certain conditions, it behaves similarly to a finite number. Furthermore, a comparative analysis of infinity, limited infinity, and sets clarifies the concept of limited infinity. To facilitate comparisons involving values represented with limited infinity, the paper proposes several comparative estimates: the absolute integral estimate, the relative average integral estimate, and the number of grid nodes of permissible errors. Additionally, the paper provides examples illustrating the application of limited infinity in practical problems such as using the quasi-constant and functional convergence methods. The introduction of the concept of limited infinity notably streamlines the utilization of various forms of infinity in applied tasks, especially when solving systems of equations with undetermined solutions.</p> O. Yu. Kimstach Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/139 Wed, 26 Jun 2024 00:00:00 +0300 CONSTRUCTING OF BIPYRAMID BASIS WITH THREE MOVABLE NODES https://st.umsf.in.ua/index.php/journal/article/view/140 <p>The article discusses the possibilities of approximation by the finite element method of the function of three variables in the region that has the shape of a quadrangular bipyramid. The main task of this study is to improve the approximation properties of lattices of the tetrahedral-octahedral structure by replenishing them with cells that are not regular polyhedra. In particular, the author studies finite elements, which are formed as a result of linear deformations of the octahedron. In this work, the object of research is a finite element in the form of a bipyramid with three movable nodes that can be moved along the semi-axes of the polyhedron. This property makes it possible to adjust a finite element that is not a regular polyhedron to the boundary of the computational domain better than a regular polyhedron. Two finite-element bases of a bipyramid with seven and six interpolation nodes are constructed in the paper. Two methods are used to construct the basic functions of the bipyramid: the geometric method and the condensation method. The obtained bases are polynomial functions that parametrically depend on the values of the three elongation/compression coefficients of the semi-axes of the bipyramid. The basis with six interpolation nodes contains an additional parameter that is a weight coefficient, which is a consequence of the application of the condensation procedure to the functions of the seven-node basis of the bipyramid. The availability of parameters allows improving the interpolation properties of the constructed bipyramid bases in accordance with the approximation quality criteria used in the finite element method. In this work, such a criterion is considered to be the value of the trace of the stiffness matrix. According to the selected criterion, the values of the linear deformation coefficients of the three semi-axes of the octahedron are found, at which the trace of the bipyramid stiffness matrix is minimal. In the article we have obtained interval estimates for the elongation/compression coefficients of the three semi-axes of the octahedron, which characterize the deviation of the geometric dimensions of the bipyramid from the regular polyhedron and lead to the loss of all types of symmetry. To determine the limits of the permissible values of the coefficients of linear deformations of the octahedron, the Skewness asymmetry index used in the ANSYS finite element analysis system was calculated. The obtained interval estimates for the elongation/compression coefficients of the octahedron semi-axes correspond to the criterion of minimality of the trace of the stiffness matrix of a bipyramid with three moving nodes, which indicates a positive prediction of the use of this finite element as a lattice cell of the tetrahedral-octahedral structure. Prospect for further research is the construction of cubature formulas on a finite element in the form of a bipyramid with three moving nodes in order to use it in the algorithmization of the finite element method.</p> A. P. Motailo Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/140 Wed, 26 Jun 2024 00:00:00 +0300 ALGORITHM FOR THE CONSTRUCTION AND OPTIMIZATION OF THE TERRITORIAL LOCATION OF SOUND SOURCES OF EMERGENCY NOTIFICATION SYSTEMS OF THE POPULATION https://st.umsf.in.ua/index.php/journal/article/view/141 <p>The article is devoted to the development of an algorithm for solving the problem of optimizing the territorial placement of elements of the public emergency notification system according to the criterion of maximizing the coverage of the territory of the settlement with the permissible power level of sound signal sources based on the application of genetic algorithms. The relevance of the article is due to the need to improve modern systems of emergency notification of the population, especially in cases where it is necessary to take into account the characteristics of certain territories. This problem is quite important in today’s world of permanent emergency situations, and the high-quality distribution of emergency notification sources can become one of the important elements of the system of warning and timely response to disasters. One of the most effective technologies for building such systems is the use of genetic algorithms, which ensure the search for the most effective options in a dynamic mode with the possibility of their further optimization. Therefore, the development and improvement of methods of rational placement of sources and optimization of the technical characteristics of the system of emergency notification of the population is an urgent problem for the safety and preservation of the health of the population. The purpose of this article is to develop an algorithm for structural optimization of the territorial placement of sound signal sources of the public emergency notification system according to the criterion of maximizing the coverage of the territory of the settlement with the permissible power level of sound signal sources based on the modification of the genetic algorithm. In accordance with the proposed approach, the function of maximum coverage of the territory of the settlement with a minimum number of sound signal sources of permissible power is used as an optimization criterion. In the process of searching for the optimal structure of the territorial arrangement of elements of the notification system, a modified genetic algorithm of analysis and determination of the most effective options is used. As a condition for building an optimal solution to the problem, the condition of complete coverage of the territory of the population with sound warning signals is defined. According to the results of the conducted research, it was found that the developed algorithm allows determining the optimal structure of the territorial placement of sound signal sources of the emergency public notification system based on the criterion of maximizing the coverage of the territory of the settlement with the permissible power level of the sound signal sources.</p> A. M. Pasichnyk, M. Yu. Ripa Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/141 Wed, 26 Jun 2024 00:00:00 +0300 WAYS OF OPTIMIZING CROSS-PLATFORM APPLICATION USING THE REACT LIBRARY AND THE REACT NATIVE FRAMEWORK https://st.umsf.in.ua/index.php/journal/article/view/142 <p>In today’s world, with the growing use of mobile devices, the importance of creating cross-platform applications that provide high performance and quality of user experience has increased significantly. Improving the creation of such applications using React and React Native opens up wide opportunities for developers due to the possibility of code reuse, high development speed and ease of innovation, and is especially relevant because it concerns not only the technological aspects of development, but also economic efficiency, quality of user experience and the speed of introducing innovations to the software market. Open source and active community communication allow rapid identification and resolution of issues, development of new features and enhancements, and the sharing of knowledge and experience between developers. This creates a positive environment for innovation and growth, promotes rapid technological progress, and improves the quality of end products. The paper analyzes the key aspects and challenges associated with the creation of cross-platform applications, analyzes the main types of optimizations at different levels of development, including the component level, the state and data level, the level of working with APIs and external data, as well as the loading and code level. Special attention is paid to the integration of synchronous and asynchronous rendering to achieve optimal performance and user experience. Highlights the benefits of flexible state management using state managers, as well as the importance of image and media optimization to improve overall website performance. The article notes the role of the developer community in the process of improvement and innovation. Developers who master these technologies and optimize their application can create products that not only meet the requirements of the time, but also form new standards in the field of mobile and web development. Further research and integration of the latest technologies into the development process of cross-platform applications will have a significant impact on the software industry.</p> О. І. Bezverhiy, О. І. Kutsenko Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/142 Wed, 26 Jun 2024 00:00:00 +0300 COMPUTER INTELLIGENCE TECHNOLOGIES USAGE FOR IMAGES ANALYSIS WITH THE PURPOSE OF DEVELOPING AND DESIGNING A DECISION SUPPORT SYSTEM FOR MONITORING AND PREVENTION OF FOREST FIRES IN UKRAINE https://st.umsf.in.ua/index.php/journal/article/view/143 <p>The article presents the results of research and development of a neural network model for monitoring natural emergencies, namely forest fires in Ukraine. A study of forest fires on the territory of Ukraine was conducted. Image analysis was carried out. A neural network model was built. It was pointed out that the development and design of the DSS for monitoring and preventing forest fires in Ukraine based on AI technologies and image analysis is a scientifically new task. The results of the study can be used for the development and implementation of more effective and reliable forest fire monitoring and prevention systems in Ukraine. A detailed analysis of the literature on the topic was carried out. Weaknesses were identified and tasks for research were set. The study was carried out using images from the open sources of the NASA Earth Observatory. Python libraries: Keras, TensorFlow, PyTorch were used to process and analyze satellite images. With the help of modeling methods, the system architecture is designed and usage options are shown. It was found that an effective approach to reducing the risk of natural disasters is the development and implementation of a modern decision support system (DSS) for each region of Ukraine. Such a DSS accumulates information about the technical, social and economic characteristics of the region in order to build an effective strategy for the prevention of natural disasters. The neural network learning model was given as follows. The dataset contains raw images where they are labeled as fire, no fire, or fire initiation. The image needs to be further processed before it can be used to train the model. The article describes the learning algorithm of a neural network. A formula was presented with a detailed explanation of the coefficients. Several different neural network models were built to identify the most effective learning option. As a result of convolutional neural network training, it was found that it is best to use all features for training. A neural network accuracy of 92% was achieved. In the future, the algorithm can be improved to improve accuracy. The results of the neural network were used for the SPPR for the early detection and prevention of forest fires in Ukraine.</p> N. V. Holovina Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/143 Wed, 26 Jun 2024 00:00:00 +0300 DESIGNING, DEVELOPING AND TESTING A WEB SERVICE FOR SELECTING THESIS TOPICS https://st.umsf.in.ua/index.php/journal/article/view/144 <p>The paper discusses the design, development, and testing of a web service for selecting topics for student theses. This application serves both educators and students by facilitating the creation, storage, and distribution of thesis topics among university students. REST API is an architectural style used to implement web services. It relies on simple and standardized principles, such as using standard HTTP methods to interact with resources via URIs, supporting stateless communication between clients and servers, facilitating data transmission in XML and JSON formats, and dividing responsibilities for scalability and system robustness. Utilizing REST API simplifies the development, deployment, and maintenance of web applications, enhancing their scalability and efficiency. The web service is developed using the Java programming language and uses the Spring framework, including Spring Boot, Spring Data JPA, Spring Web, and Spring Security. The project structure follows the Controller-Service-Repository design pattern, which organizes functionality into corresponding layers. The controller layer defines the external interface of the service and handles data provision to clients. The repository layer is responsible for data storage and retrieval, while the service layer contains all business logic. If the business logic requires data retrieval or storage, it interacts with the repository. Clients access the business logic by invoking classes from the controller layer. PostgreSQL is used as the data storage. Testing is a crucial component of software development. The web service will undergo unit tests to verify individual components, integration tests to examine component interaction, and API tests to ensure the functionality of the service’s API. Swagger and Postman are used for testing REST API functionality. The Testcontainers library facilitates the creation of tests using real dependencies with Docker containers, simplifying testing with real services. The web service automates the process of creating and selecting thesis topics for educators and students, respectively.</p> Yu. F. Oleksiichuk, D. M. Olkhovsky, O. V. Оlkhovska, O. M. Andrushkiv Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/144 Wed, 26 Jun 2024 00:00:00 +0300 SOME SOCIO-ECONOMIC ASPECTS OF THE USE OF DATA CENTERS https://st.umsf.in.ua/index.php/journal/article/view/145 <p>The article analyses the problems associated with the development of information technologies – cloud computing and artificial intelligence systems, which resulted in the mass construction of data processing centres. Such construction has led to the emergence of a number of socio-economic and environmental problems, such as: the problem with the lack of electricity for data centres and the uneven distribution of its resources, the problem with the noise created by the cooling systems of data centres, the problem of exhaustion of water resources required for cooling data centres, etc. These problems, given their novelty, have not yet found a proper solution and have not been practically investigated in scientific papers. The analysis of publications related to this topic shows that the main focus of researchers is on the study of the impact of information and communication technologies on the socio-economic development of society and on the life, education and social interactions of people. Economic issues are considered in terms of the impact of data centre construction on local economies and the revenue generation by governments and local authorities from the construction and operation of data centres. At the same time, the social and economic problems arising from the operation of data centres are not considered enough because of their recent emergence. This article discusses the problems of organisation, design and construction of data centres, including legal issues, and the associated social, economic and environmental problems. If at the time of the emergence of cloud computing technologies (in fact, since 2012) data centres were located on sites outside major population centres and had no problems with power supply and heat dissipation from the equipment, then nowadays data centres are built within cities or in close proximity to population centres. In this case, there are significant problems with power supply and ecology, in some cases leading to redistribution of capacities in favour of data centres at the expense of infringement of interests of the population. In addition, the rejection of water cooling of data centres for environmental reasons and the switch to air cooling has created the problem of unbearable noise emitted by air-cooled data centre systems, which has led to increased social tension and mass protests by local residents. The problem is aggravated by the fact that, according to analysts, the total number of data centers in the near future may increase by 2.5 times, which will inevitably lead to a sharp increase in social tension, mass protests and undesirable economic consequences. This problem is particularly important due to its worldwide nature, since data centers are being built in all regions of the planet. It is noted that the existing difficulties and problems arise due to the fact that local authorities failed to assess the possible problems with the operation of data centres and issued permits for their construction in order to gain financial benefits for the economy of the region. This problem is of an urgent nature and requires measures, including legislative measures, which could resolve the contradiction between the need to build data centres (and additional power plants to supply them, including nuclear power plants) and the interests of people living in the immediate vicinity of the data centres. In addition, it is mandatory to take into account the impact of the consequences of such construction on the environment. There are also known cases of destruction of cultural and historical heritage during the construction and operation of data centres. An important point is the issue of security associated with the possible consequences of terrorist actions (cessation of the functioning of vital information systems, contamination of the territory with toxic and radioactive substances, shutdown of power supply to the population). The article emphasises the need to urgently develop a set of measures, including legal ones, to address and prevent socio-economic and environmental problems.</p> R. I. Chanyshev Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/145 Wed, 26 Jun 2024 00:00:00 +0300 DEVELOPMENT OF A SYSTEM OF DIGITIZATION AND CATALOGING OF PROTOCOLS OF THE TRAFFIC SAFETY COMMISSION OF THE IVANO-FRANKIVSK CITY-TERRITORIAL COMMUNITY https://st.umsf.in.ua/index.php/journal/article/view/146 <p>The article is devoted to the development of a system of digitization and cataloging of protocols and decisions of the Traffic Safety Commission of the Ivano-Frankivsk City Territorial Community (KBDR). KBDR considers the issue of implementation of measures to ensure improvement works, organization of road traffic and increase the safety of all road users on the territory of Ivano-Frankivsk urban territorial community in accordance with the master plan, projects of detailed planning and construction of settlements, projects of capital repair, reconstruction and new construction of objects of the street and road network, implementation of automated traffic control systems, complex transport schemes and traffic organization schemes, parking zones taking into account the principles of sustainable development and compliance with the rules of landscaping. From 2016 to 2024, the commission held more than a hundred meetings where more than 3,150 issues were considered. Commission protocols are drawn up in the form of PDF files and uploaded to the server. There is an urgent need to find decisions of the commission at a certain address, location, etc. Appeals from citizens, municipal inspection requires the formation of answers and excerpts whether a certain decision was made or not. The article deals with the development of a system for digitizing commission protocols and creating a catalog (a website with a database) with a quick search function. It is possible to download the original protocol to form an official extract. The database was designed and implemented using Microsoft SQL Server with the Entity Framework Core package for storing KBDR solutions. A system for digitizing PDF files of the commission’s decision and importing them into the database has been developed. A web application with a search function was built using ASP .NET Core MVC technology and Razor Views.</p> B. V. Pashkovskyi Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/146 Wed, 26 Jun 2024 00:00:00 +0300 TIME SAVINGS CALCULATION IN TEST CREATION USING ARTIFICIAL INTELLIGENCE https://st.umsf.in.ua/index.php/journal/article/view/147 <p>Distance learning has been evolving for many decades, but it garnered significant attention with the onset of the COVID- 19 pandemic when quarantine restrictions were implemented worldwide. As a result, the integration of this type of learning into traditional face-to-face education was expedited. Distance learning, with its flexibility, allowed for the continuation of the curriculum and learning almost on a self-paced schedule. However, while listing the advantages of distance learning, it also has negative impacts on health, such as deteriorating eyesight, posture, and psychological aspects. Distance learning offers numerous advantages over traditional classroom attendance, as materials can be studied anywhere, and if something is not understood, it can be reviewed again. Additionally, lectures and assignments can be downloaded to devices, allowing learning without the need for light or the internet. During distance learning, testing in the form of quizzes becomes increasingly common and relevant. The time savings calculation in test creation using artificial intelligence is an important aspect of our study. By leveraging AI algorithms, we aim to streamline the test creation process, reducing the time and effort required from instructors. This involves developing a mathematical model to quantify the amount of time saved when utilizing AI compared to traditional manual test creation methods. The results of this calculation will provide valuable insights into the efficiency gains offered by AI in educational settings, ultimately contributing to the advancement of technology-enhanced learning methodologies. This study developed a mathematical model to calculate time savings in test creation using artificial intelligence compared to manual test creation by instructors. The research showed that this approach can achieve time savings of more than 60%. The study also presents the implementation of test creation using both proposed methods (with and without AI) in a system developed using the Laravel framework. The results obtained confirm the feasibility and effectiveness of using AI in test development.</p> M. Yu. Tiahunova, H. H. Kyrychek, D. V. Kostetskyi Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/147 Wed, 26 Jun 2024 00:00:00 +0300 ASSESSMENT OF THE STATE OF INFORMATION SECURITY USING EXPERT SYSTEMS https://st.umsf.in.ua/index.php/journal/article/view/148 <p>The problems considered in the article are related to ensuring the specified indicators of efficiency and reliability of the designed software complexes for information systems through a structural approach to the main stages of the software life cycle. The relevance of this class of software is determined by the wide distribution of such systems. Distinctive features of the modern complex of programs for information systems are their large information and logical complexity, significant volumes of programs, work in conditions of a limited amount of computing resources with high requirements for the efficiency and reliability of their functioning, as well as a pronounced production and technical nature of software tools for all life cycle stages. The main problem associated with the creation of complex software systems is to increase the reliability of programs. One of the promising ways to solve the problem is the implementation of a detailed regulated technological process. At the same time, the required level of regulation has been achieved as a result of a structural approach to ensuring reliability at various stages of software life. Among the known ways to improve the reliability of software, this article pays special attention to progressive methods of creating programs and the widespread use of automation tools, since the technology under consideration and its instrumental support are based on a structural approach to software development. The role and influence of the corresponding structural methods on the reliability characteristics of the software is shown. In general, the structural approach makes it possible to increase the efficiency of working with software based on the implementation of three provisions: streamlining and unifying the structural construction of the software package; ordering work to eliminate errors; creating conditions for the effective application of assembly programming technology based on the software backlog.</p> V. O. Voskoboinyk, Iu. V. Savchenko, L. M. Karpukov, O. A. Parshyna, D. I. Prokopovych-Tkachenko Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/148 Wed, 26 Jun 2024 00:00:00 +0300 PECULIARITIES OF COMMERCIAL ACTIVITY IN MIXED COMBINED TRANSPORT https://st.umsf.in.ua/index.php/journal/article/view/149 <p>The article examines topical issues related to commercial activities in the context of mixed combined transport and ways to improve the tariff system on the example of road and rail transport. One of the main ways to improve the tariff system is to differentiate it depending on the quality class of transportation and other transport services, as well as to gradually stop the practice of "cross-financing" and subsidising unprofitable activities at the expense of profitable ones. Today, the transport sector is able to meet only the basic needs of the population and the economy in terms of transportation volumes, but not in terms of quality. The current state of the transport sector does not fully meet the requirements for the effective implementation of Ukraine's European integration course and the integration of the national transport network into the Trans-European Transport Network. To improve the efficiency and competitiveness of the transport sector, it is necessary to improve the legal mechanism for public- private partnerships, strengthen cooperation between the public and private sectors, state authorities and local governments, and implement the necessary reforms, including the introduction of decentralisation through coordinated public policy initiatives. This will create a solid foundation for the sustainable development of the transport sector and an open, competitive transport market. In accordance with the current legislation, the level of tariffs in transport is determined based on the standard costs per unit of transport work, profitability and tax liabilities. Settlements with consumers of public transport services are carried out in accordance with the current tariffs in accordance with the codes (charters) of certain types of transport, other legislative acts of Ukraine, as well as in accordance with international conventions to which Ukraine is a party and interstate agreements in the field of transport services. The authors propose a methodology for setting tariffs for mixed combined transportation based on an assessment of the efficiency of the entire transport system. Since mixed combined transport, in particular, containerised transport, combines the accuracy of road transport with costs similar to those of rail transport, the tariff for it should be in the range between the tariff for traditional rail transport and road transport.</p> P. V. Lubiany, O. A. Voitovych, I. O. Kuzmenko Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/149 Wed, 26 Jun 2024 00:00:00 +0300 FINDING WAYS TO IMPROVE RADIO-ELECTRONIC NAVIGATION SYSTEMS OPERATIONAL EFFICIENCY https://st.umsf.in.ua/index.php/journal/article/view/150 <p>Modern aircraft are equipped with digital pilotage and navigation systems of the new generation, in which all systems have built-in control systems and are structurally made in the form of a number of easily replaceable blocks. The flight safety of modern aircraft is ensured by the redundancy of radio-electronic navigation systems, while the regularity of flights is ensured by the creation of a sufficient number of spare easily replaceable blocks in the exchange fund. The article notes that the high integration of pilotage and navigation complexes and the high intensity of aircraft flights leads to the fact that, according to the results of operational maintenance, part of easily replaceable blocks are mistakenly recognized as inoperable, dismantled and sent for restoration. According to statistics, from 40 to 85% of disassembled easily replaceable units of radio electronic navigation systems are actually functional. This gives rise to the problem of so-called unconfirmed defects. The North American Air Transport Association (ATA) estimates annual losses at an average of 100,000 thousands of dollars for each medium-haul aircraft. A large number of unconfirmed defects entails the need for an unjustified increase in the volume in the exchange fund of spare easily replaceable units to maintain the regularity of flights, which leads to significant capital costs. This work is devoted to the search for opportunities to reduce these costs through the use of ground-based automated control systems, that verify dismantled blocks with high reliability and prevent erroneous sending of workable easily replaceable blocks for restoration. However, purchasing and operating ground-based automated control systems also requires significant investment. The article defines that the efficiency of aircraft operation is directly determined by the optimal variant of the organization of the maintenance and repair system, the choice of which is based on the solution of the complex tasks of diagnostic support, methodical, regulatory support and optimal formation of the exchange fund.</p> S. V. Rahulin, V. O. Zubenko Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/150 Wed, 26 Jun 2024 00:00:00 +0300 EVALUATION OF THE INFLUENCE OF THE AERODYNAMIC COEFFICIENTS OF THE FRONTAL RESISTANCE FORCE OF THE PROJECTILE ON ITS FLIGHT DISTANCE https://st.umsf.in.ua/index.php/journal/article/view/151 <p>An urgent and important issue in the creation and development of promising anti-artillery systems and ammunition for them is the introduction of automated control systems with the wide use of ballistic computers, which include new approaches to ballistic and meteorological data preparation for firing, the mathematical basis of which are ballistic integrating algorithms for calculating installations for firing based on solving the inverse problem of external ballistics. An important component of the aerodynamic force vector acting on the projectile is the drag force, which has a direction opposite to the direction of the projectile’s velocity and significantly affects the dynamics of its flight. The practical application of the theoretical provisions of the research of frontal resistance is their use for calculating projectiles flight trajectories and compiling the firing tables of artillery systems, therefore, the accuracy of the tabular range calculation is taken as a measure of the accuracy of its determination. The analysis of requirements for the accuracy of calculation of the tabular range of artillery systems shows that the value of the median error at short firing ranges has a value of the order 0.50% of the flight range, at long ranges – (0.25 ÷0.30)%. The experimental study of the drag force is reduced to the study of its aerodynamic coefficients at different values of Mach numbers. In addition, it is important to evaluate the influence of both the linear and non-linear components of the aerodynamic drag force coefficient on the range of the projectile. To evaluate the influence of aerodynamic coefficients on the flight range of the projectile, the difference method was used, which consists in solving the system of differential equations of spatial motion of a projectile so that, by changing the value of each of the component aerodynamic coefficients, a change in the value of the flight range is obtained. Numerical modeling of the dependence of the flight range error of 155-mm HE projectiles – Assegai M2000 and ERFB/BB on a change in the value of their aerodynamic coefficients by 1%. It is shown that the largest error in the flight range of the projectile is introduced by the linear coefficient of the force of frontal resistance when firing at the maximum charge – 0.9% of the firing range, respectively, the smallest, at the minimum charge – 0.13%. In addition, the simulation results showed that the influence of the quadratic coefficient of the frontal drag force has 1-2 orders of magnitude smaller values compared to the linear one.</p> S. V. Bondarenko, Yu. M. Kosovtsov, Z. M. Hrabchak Copyright (c) https://st.umsf.in.ua/index.php/journal/article/view/151 Wed, 26 Jun 2024 00:00:00 +0300