Eastern-European Journal of Enterprise Technologies 2024-05-24T16:29:52+03:00 Frolova Liliia Open Journal Systems <p><span lang="EN-US">Terminology used in the title of the «Eastern-European Journal of Enterprise Technologies» - «enterprise technologies» should be read as «industrial technologies». <strong>«Eastern-European Journal of Enterprise Technologies»</strong> publishes all those best ideas from the science, which can be introduced in the industry. Since, obtaining the high-quality, competitive industrial products is based on introducing high technologies from various independent spheres of scientific researches, but united by a common end result - a finished high-technology product. </span>Among these scientific spheres, there are information technologies and control systems, engineering, energy and energy saving. Publishing scientific papers in these directions are the main development «vectors» of the «Eastern-European Journal of Enterprise Technologies». Since, these are those directions of scientific researches, the results of which can be directly used in modern industrial production: space and aircraft industry, instrument-making industry, mechanical engineering, power engineering, chemical industry and metallurgy.</p> <p><span lang="EN-US">Therefore, the scientists, associated with modern production, have the opportunity to participate in <strong>technology transfer to industry</strong>, publishing the results of their applied scientific researches. Industrialists, in turn, can draw scientific and practical information from the journal - each in their direction:</span></p> <ul> <li>specialists in management and computer science - from volumes «Applied Information Technologies and Control Systems», «Mathematics and Cybernetics - Applied Aspects»;</li> <li>mechanical and design engineers - from the volume «Applied Mechanics»;</li> <li>production engineers - from volumes «Mechanical Engineering Technology», «Applied Physics», «Materials Science», «Technology of organic and inorganic substances and the Ecology»;</li> <li>production and power engineers - from the volume «Energy-saving technology and equipment».</li> </ul> <p><span lang="EN-US"><strong>The goal of the journal</strong> is to eliminate the gap, which occurs between the rapidly emerging new scientific knowledge and their introduction in the industry, which requires much more time. Industrial enterprises are active subscribers to the «Eastern-European Journal of Enterprise Technologies», and production engineers check the practical value of those scientific and technological ideas, which are recommended for implementation by scientists-authors of the ''Eastern-European Journal of Enterprise Technologies».</span></p> <p><span lang="EN-US"><strong>The objective of the journal</strong> in achieving the goal is <strong>forming a «scientific component» of modern technologies transfer</strong> from science to industry. Therefore, in the papers, published in the journal, the emphasis is placed on both scientific novelty, and practical value.</span></p> Optimization of cross-sectional dimensions of castellated beams with hexagonal openings 2024-05-24T16:29:52+03:00 Vitalina Yurchenko Ivan Peleshko Pavlo Rusyn <p>The object of this study is a castellated beam, in which the web openings have the shape of a regular hexagon. The beam is examined to find optimal cross-sectional dimensions. The optimization task is stated as the task of finding the optimal profile numbers for top and bottom Tees of the beam and the optimal width of the web opening while ensuring the required load-carrying capacity of the beam. Minimization of the volume of the beam material was considered as an optimality criterion. The stated optimization problem was solved using the exhaustive search method. For an assortment of normal I-beams with parallel flanges, castellated beams were obtained with optimal cross-sectional dimensions depending on the steel grade, the beam span, and the magnitude of transverse uniformly distributed load. The optimization calculations proved that it was possible to increase the elastic section modulus of the beam to 35.48...50 % through the use of a castellated web. Castellated beams with optimal cross-sectional dimensions at the same load-carrying capacity are characterized by lower steel consumption (up to 23.19 %) compared to I-beams with a solid web. Analysis of the results has made it possible to devise recommendations for the optimal distribution of material in the cross-sections of such beams. The results are valid only for the assortment of normal I-beam profiles and only for the case of uniformly distributed load acting on the beam when the compressed beam flange is laterally restrained from the bending plane and the beam web has openings in the form of regular hexagons. It is under such conditions that the reported results can be implemented in practice both at the stage of selecting cross-sections of the studied class of structures, and at the development of effective assortments of castellated beams</p> 2024-06-03T00:00:00+03:00 Copyright (c) 2024 Vitalina Yurchenko, Ivan Peleshko, Pavlo Rusyn Determining the influence of façade parameters and the width of a fire-proof eaves on preventing the spread of fire through external vertical structures of buildings 2024-05-09T22:18:44+03:00 Oleksandr Kagitin Roman Veselivskyi Andrii Havrys Yaroslav Ballo Roman Yakovchuk Bohdan Kovalyshyn <p>The object of this study is the process of fire propagation through the surface of external wall structures with facade thermal insulation. The paper examines the influence of facade parameters and the width of a fire-proof eaves on preventing the spread of fire by external vertical structures using the example of a residential building. With the use of FDS modeling, the relationships between the parameters of external enclosing structures and the fire-proof eaves on the processes of limiting the spread of fire were investigated. The influence of the minimum parameters of the height of the inter-floor windowsill in the absence of a fire-proof eaves on the spread of fire was determined. The dependence of temperature change near the surface of the facade on the width of the fire-proof eaves and the height of the window between floors was established.</p> <p>Based on a series of simulated experiments, it was established that with a height of 1.0 m between floors and the absence of a fire-proof eaves, the critical temperature value is 250 °C. This value corresponds to the destruction temperature of a standard metal-plastic window structure. For the case when the wall height is 1.0 m, and the width of the fire-proof eaves is 0.75 m, the temperature value is 180 °C. That is, the safety condition of 250 °C is met.</p> <p>Based on the research, a dependence was found on the criterion of not exceeding the critical temperature of 250 °C at the level of 1.4 m of the facade of the building floor located above the fire floor. The criterion holds when the width of a fire-proof eaves is at least 0.4 m and the height of the window partition is 1.0 m, as well as when the width of the eaves is 0.5 m, and the height of the window partition is 0.6 m.</p> <p>It was established that the height of a window interfloor partition has a smaller effect than the width of the fire-proof eaves that separates the floors that are located above</p> 2024-05-16T00:00:00+03:00 Copyright (c) 2024 Oleksandr Kagitin, Roman Veselivskyi, Andrii Havrys, Yaroslav Ballo, Roman Yakovchuk, Bohdan Kovalyshyn Assessing the stability of protective structures in preparatory mining workings under conditions of static load 2024-05-23T19:23:37+03:00 Daria Chepiga Serhii Podkopaiev Oleksiy Kayun Anatolii Bielikov Yevgen Podkopayev Oleksandr Kipko Olha Pidhurna <p>The object of this study is the deformation processes in protective structures under the action of static load in the coal massif in order to preserve the integrity of the side rocks and the operational condition of mine workings. Under laboratory conditions, the deformation characteristics of rigid and flexible protective structures, as well as supports made of crushed rock, were studied on experimental samples. The samples were subjected to uniaxial compression. It was established that there is a functional relationship between the coefficient of transverse deformation ν and the relative change in the volume δV of protection structures, which makes it possible to estimate their bearing capacity. For rigid protection structures (coal pillars, cast strip, cement blocks, blocks of reinforced concrete bollards, bundles of wooden racks), the deformed state of the structures determines their behavior. This happens at values of ν=0.3–0.5 and δV£0.09. Their stability is fixed within the safe deformation resource. An increase in the deformation energy density of such structures beyond the safe deformation resource leads to their destruction due to a change in shape. For flexible protection structures (bundles of wooden racks, rolling bundles made of wooden sleepers), which have a transverse deformation coefficient ν=0.02, at a relative change in volume δV£0.3, the compaction of structures is observed. Increasing their stiffness allows limiting the convergence of side rocks.</p> <p>For a support made of crushed rock, at ν=0.25–0.32 and a relative volume change of 0.12£δV£0.32, its compaction and increase in resistance occur. Under such conditions, the convergence of side rocks is limited. In order to preserve the integrity of the lateral and operational condition of preparatory workings in the excavation areas of coal mines, it is advisable to use flexible protective structures made of wood or supports made of crushed rock</p> 2024-05-31T00:00:00+03:00 Copyright (c) 2024 Daria Chepiga, Serhii Podkopaiev, Oleksiy Kayun, Anatolii Bielikov, Yevgen Podkopayev, Oleksandr Kipko, Olha Pidhurna Determining infrared radiation intensity characteristics for the exhaust manifold of gas turbine engine ТВ3-117 in МІ-8МSB-B helicopter 2024-05-07T18:34:56+03:00 Mykhailo Kinashchuk Ihor Kinashchuk <p>The object of this study is the screen-exhaust device in the TV3-117 engine of the Mi-8MSB-B helicopter.</p> <p>To reduce visibility in the thermal range, a system of mixing hot engine exhaust gases with ambient air is used; this technique makes it possible to reduce the infrared radiation of engines. For this purpose, a new sample of screen-exhaust device was designed for testing.</p> <p>A thermal imaging survey of the helicopter was conducted. Three variants of thermal images were acquired: a helicopter without installation of a thermal visibility reduction system, a helicopter with standard exhaust shields installed, and a helicopter with newly developed shield exhaust devices installed. Based on the obtained experimental results, the characteristics of the intensity of infrared radiation were determined for three variants of research in the range of thermal waves of 3–5 μm. The study uses a comprehensive approach to solving the tasks, which includes a statistical analysis of known and promising ways to protect a helicopter from guided missiles with infrared homing heads based on reduced radiation forces and a theoretical method for calculating flow and temperature fields. The advantages of placing the section of the exhaust channel of the designed screen-exhaust device in the horizontal plane for complete shielding of infrared radiation in the lower hemisphere have been experimentally proven. The benefits of directing the flow of exhaust gases from the screen-exhaust device into the space above the helicopter propeller and dividing this flow into four separate flows were shown. The results of experimental research could be used to design new or improve existing screen-exhaust devices by the developers of military aviation</p> 2024-05-16T00:00:00+03:00 Copyright (c) 2024 Mykhailo Kinashchuk, Ihor Kinashchuk The approach development of data extraction from lambda terms 2024-02-23T18:21:18+02:00 Oleksandr Deineha Volodymyr Donets Grygoriy Zholtkevych <p>The study's object is the process of extracting the characteristics of lambda terms, which indicate the optimality of the reduction strategy and increase the productivity of compilers and interpreters. The solution to the problem of extracting specific strategy priority data from lambda terms using Machine Learning methods was considered.</p> <p>Such data was extracted using the large language model Microsoft CodeBERT, which was trained to solve the problem of summarizing the software code. The resulting matrices of embeddings were used to obtain vectors of average embeddings of size 768 and a latent space of size 8 thousand. Further, vectors of average embeddings were used for cluster analysis using the DBSCAN and Hierarchical Agglomerative clustering methods. The most informative variables affecting clustering were determined. Next, the clustering results were compared with the priorities of reduction strategies, which showed the impossibility of separating terms with RI priority. A feature of the obtained results is using machine learning methods to obtain knowledge.</p> <p>The clustering results showed many of the same informative variables, which is explained by the similar shape of the obtained clusters. The results of comparing the clustering values with the real priority are explained by the impossibility of clearly determining the priority and the use of the Microsoft CodeBERT model, which was not trained for the analysis of lambda terms.</p> <p>The proposed approach can find application in the development of compilers and interpreters of functional programming languages, allowing to analyze the code and extract important data to optimize the execution of programs. The obtained data can be used to develop rules aimed at improving the efficiency of compilation and interpretation</p> 2024-05-16T00:00:00+03:00 Copyright (c) 2024 Oleksandr Deineha, Volodymyr Donets, Grygoriy Zholtkevych