Journal of Engineering Sciences / Журнал інженерних наук
Permanent URI for this collectionhttps://devessuir.sumdu.edu.ua/handle/123456789/34326
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Item Optimal management in the operation of complex technical systems(Sumy State University, 2024) Дядюра, Костянтин Олександрович; Diadiura, Kostiantyn Oleksandrovych; Oborskyi, G.; Prokopovych, I.; Khamitov, V.; Holubiev, M.Developing a cost management system for a complex technical system (CTS) at the stages of its life cycle is a modern trend aimed at creating sustainable cooperation ties based on requirements, including those of manufacturers and consumers. The article explores the concept of a complex technical system. The principles and properties of a complex technical system were described. A model of a procedure for checking the operability of a complex technical system with an arbitrary distribution of the time of independent manifestation of a failure was proposed for the example of compressor station equipment. Models of operation of complex technical systems based on information about their state were considered. It was also shown how to optimize maintenance decisions for these systems in terms of the minimum average unit cost and how reliable this ensures. Additionally, proof of the existence of an optimal verification strategy was given. An algorithm for determining the moments of verification was developed to ensure the minimum cost. The methods of collecting, processing, and effectively using information for making decisions about the technical condition of complex products and the possibility of further exploitation were improved based on selecting informative diagnostic features and constructing models that comprehensively consider the maximum and current level of their parameters. This allowed for the quality of the final products to be ensured. The practical use of the proposed methods of diagnosis and forecasting made it possible to increase the actual CTS resource by 1.5–2.0 times. This also increased the productivity of the technological process by 1.6 times due to the reduction of the number of stops for maintenance for replacement, adjustments, and sub-adjustments. As a result, the value of the lack of basic production was reduced from 1.2 % to 0.8 %, and the cost of manufacturing products was decreased by 1.2–2.0 times.Item Investigation of the blockchain structure for hydroxyapatite-based scaffolds(Sumy State University, 2021) Чернобровченко, Вадим Сергійович; Чернобровченко, Вадим Сергеевич; Chernobrovchenko, Vadym Serhiiovych; Дядюра, Костянтин Олександрович; Дядюра, Константин Александрович; Diadiura, Kostiantyn Oleksandrovych; Panda, A.Regenerative biomechanics provides exciting technologies for developing functional substitutes, intending to restore and regenerate damaged tissues and organs. Scaffolds are in great demand. However, there are risks of biocompatibility when using scaffolds. Each bone substitute has its chemical composition, and other characteristics have advantages and disadvantages. Reproducibility, data sharing, privacy concerns, and patient participation in clinical trials are significant problems in modern clinical trials. In the era of the Internet, data is collected constantly. Today we need applications that ensure the privacy of users’ data. Blockchain technology helps to compensate for severe data management problems (e.g., patient recruitment, ongoing monitoring) in clinical trials (CT). The article examines the principles of blockchain operation and approaches to bone substitutes’ design. Based on this data, a blockchain model for biomaterial surgery has been created, facilitating interaction between the parties and reducing errors.Item Influence of technological manufacturing conditions on the porosity of calcium-phosphate scaffolds(Sumy State University, 2021) Chernobrovchenko, V.S.; Дядюра, Костянтин Олександрович; Дядюра, Константин Александрович; Diadiura, Kostiantyn Oleksandrovych; Balynskyi, M.; Panda A., A.The implantation of bone substitutes depends on the material’s osteoconductive potential and the structure's porosity Porosity is a characteristic feature of most materials. The porosity of materials has a strong influence on some of their properties, both structural and functional. An essential requirement for bone scaffolds is porosity, which guides cells into their physical structure and supports vascularization. The macroporosity should be large enough and interdependent for bone ingrowth to occur throughout the entire volume of the implant. The pore size for cell colonization in bioceramics is approximately 100 μm. Pores larger than this value promote bone growth through the material. This pore size allows the flow of growth factors and cell adhesion and proliferation, allowing the formation of new bone and developing the capillary system associated with the ceramic implant. Porosity also affects the rate of resorption of ceramics: the larger the number of micropores, the higher the dissolution rate. The investigated properties were elastic moduli, ultimate strength, compressive strength, and average apparent density. The results obtained in this work are consistent with previous studies, proving the positive role of microporosity in osseointegration and bone formation.Item Research of the structure and properties of antifriction composites with modified polytetrafluoroethylene matrix(Sumy State University, 2014) Говорун, Тетяна Павлівна; Говорун, Татьяна Павловна; Hovorun, Tetiana Pavlivna; Дядюра, Костянтин Олександрович; Дядюра, Константин Александрович; Diadiura, Kostiantyn Oleksandrovych; Berladir, K.V.; Vyshehorodtseva, M.E.; Ustimenko, M.S.Structures of the powdered polytetrafluoroethylene (PTFE) before and after intensive mechanical activation (mechanical alloying) are investigated by the set of physical research methods. Enhancement of physical and mechanical properties and structuring activity of polytetrafluoroethylene as matrix of composites by means of mechanical activation is shown. Operating modes of mechanical activation equipment are defined, in which the service properties of PTFE are maximized. The effect of mechanical activation technology on restructuring and change of morphology and supramolecular structure of PTFE is detected for the first time. Obtained results and examples of implementation of the developed tribotechnical composites are analyzed.