Eastern-European Journal of Enterprise Technologies最新文献

{"title":"Development of method for frequency regulation of output current in high-voltage transformerless resonant chargers of capacitive energy storage devices","authors":"D. Vinnychenko, Natalia S. Nazarova, Iryna Vinnychenko","doi":"10.15587/1729-4061.2024.299031","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.299031","url":null,"abstract":"The object of research is high-voltage systems of electric discharge installations for various technological purposes. The work reports solving the problem of enabling the rate of charging of a capacitive energy storage, set by the requirements of a certain high-voltage technology.\u0000The quantitative characteristics of the deviation of the output current of the resonant inverter from the set stabilized value when changing the switching frequency of inverter switches in the range of output voltage change from 0 to 20 kV were determined. Using the Fourier transform of the rectangular input voltage, the frequency regulation possibility of the output current of the charger for capacitive energy storage devices was analyzed. Estimation dependences of the output current of resonant inverter on the load resistance and frequency deviation from resonant frequency were derived. These dependences could be used to implement frequency control over the switching inverter transistors, with the help of which the given effective value of the output current of the resonant inverter is obtained.\u0000A method of frequency regulation of the output current in high-voltage transformerless resonant charging devices of capacitive energy storage devices has been developed. Special feature of this method is that it is based on the frequency dependence of reactive resistances of the inductance and capacitance of the resonant circuit connected in series. Owing to that, it makes it possible to adjust the switching frequency of the inverter’s power switches depending on the relative resistance of the load and the specified growth rate of the capacitive energy storage voltage.\u0000The results reported here could be used in the design of benches for testing the electrical strength of high-voltage cables, as well as for the construction of high-voltage transformerless chargers in systems of electric discharge impulse processing of materials","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"57 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140419790","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}

{"title":"Determining the effect of a floating point on the Falcon digital signature algorithm security","authors":"Oleksandr Potii, O. Kachko, S.O. Kandii, Yevhenii Kaptol","doi":"10.15587/1729-4061.2024.295160","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.295160","url":null,"abstract":"The object of research is digital signatures. The Falcon digital signature scheme is one of the finalists in the NIST post-quantum cryptography competition. Its distinctive feature is the use of floating-point arithmetic. However, floating-point arithmetic has so-called rounding noise, which accumulates during computations and in some cases may lead to significant changes in the processed values. The work considers the problem of using rounding noise to build attacks on implementation. The main result of the study is a novel attack on implementation, which enables the secret key recovery. This attack differs from existing attacks in using two separately secure implementations with different computation orders. As a result of the analysis, the conditions under which secret key recovery is possible were revealed. The attack requires 300,000 signatures and two implementations to recover key. The probability of successful attack ranges from 70 % to 76 %. This probability is explained by the structure of the Gaussian sampling algorithm used in the Falcon digital signature. At the same time, a necessary condition for conducting an attack is identical seed during signature generation. This condition makes the attack more theoretical than practical since the correct implementation of the Falcon makes probability of two identical seeds negligible. However, the possible usage of floating-point noise shows potential existence of additional attack vectors for the Falcon that should be covered in security models. The results could be used in the construction of digital signature security models and their implementation in existing information and communication systems","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"29 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140420273","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}

{"title":"Convergence of dominant forms of investment capital in the development of socio-economic systems","authors":"V. Prokhorova, Svitlana Mushnykova, A. Zaitseva, Olga Gavrysh","doi":"10.15587/1729-4061.2024.299127","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.299127","url":null,"abstract":"The object of this study is the dominant forms of investment capital and their convergence according to the stages of development of socio-economic systems. Any evolution has certain stages. The development of socio-economic systems is no exception. All processes and phenomena in the world, including development, occur cyclically and are interconnected with the stages of natural, social, and economic processes. According to the theory of economic cycles, such phenomena as the development of the socio-economic system, its crisis and innovations have a close relationship. Industrial revolutions became a vivid example of changes in the socio-economic development of complex systems. One of the main sources of financing for each stage of the industrial revolution is investment capital, which can be part of industrial, private, financial, banking, or intellectual capital. Depending on the signs of social relations, social system, etc. can take their forms.\u0000Each of the stages of the industrial revolution is preceded by appropriate conditions that are associated with certain historical conditions at a specific moment in time. Considering the dominant forms of investment capital according to the stages of the industrial revolution, the reasons for their change should be noted. The process of convergence of investment capital is considered here.\u0000One of the indicators that characterizes the efficiency of investment capital is its mobility or immobility. A number of macroeconomic factors affect the mobility of investment capital.\u0000Considering the world structure of direct foreign investments, the main directions of their utilization have been indicated. The model of the convergence of the dominant forms of investment capital in the logistics system is presented in accordance with the stage of the industrial revolution and the features that accompany it","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"17 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140420339","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}

{"title":"Construction of homogeneous solutions of the torsion problem for a radially inhomogeneous transversely isotropic cylinder","authors":"N. Akhmedov","doi":"10.15587/1729-4061.2024.298737","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.298737","url":null,"abstract":"The torsion problem for a radially inhomogeneous transversely isotropic cylinder of small thickness was investigated by the method of asymptotic integration of elasticity theory equations. It is assumed that the side part of the cylinder is stress-free, and boundary conditions are set at the ends of the cylinder, leaving the cylinder in equilibrium. The elastic moduli are thought to be arbitrary continuous functions of the variable along the cylinder radius. The formulated boundary value problem is reduced to a spectral problem containing a small parameter characterizing the thin-walledness of the cylinder. Homogeneous solutions are built, i.e. any solutions of the equilibrium equation satisfying the condition of no stresses on the side surfaces. It is shown that the solution of the torsion problem consists of a penetrating solution and a boundary layer character solution similar to Saint-Venant's edge effect in the theory of inhomogeneous plates. The penetrating solution determines the internal stress-strain state of a radially inhomogeneous cylinder. The stress state determined by the penetrating solution is equivalent to the torsional moments of stresses acting in the cross-section perpendicular to the cylinder axis. Solutions having the boundary layer character are localized at the ends of the cylinder and decrease exponentially with distance from the ends. These solutions are absent in applied shell theories. Asymptotic formulas for displacement and stresses are built, which make it possible to calculate the three-dimensional stress-strain state of a radially inhomogeneous transversely isotropic cylinder of small thickness. Based on the obtained asymptotic expansions, it is possible to assess the applicability of applied theories and build a refined applied theory for radially inhomogeneous cylindrical shells","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"225 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140420815","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}

{"title":"Development of a natural language chatbot interface for website users","authors":"Yurii Lynnyk, Lyubov Krestyanpol, Elina Rozvod","doi":"10.15587/1729-4061.2024.299200","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.299200","url":null,"abstract":"Today, there are a variety of technology solutions for creating chatbots, including universal platforms such as Google's Dialogflow, Microsoft's Azure Bot Service, and IBM's Watson Assistant, as well as chatbot builders such as ActiveChat, SendPulse, and BotPress. The disadvantage of the considered platforms and designers is the limitation of the free plan.\u0000This study considered the development and integration of an informative chatbot into the department's website in order to create a virtual assistant for potential applicants and applicants. The relevance of the study is due to the modern conditions of admission, limited opportunities to conduct career guidance events in connection with the consequences of the COVID 19 pandemic and the war on the territory of Ukraine.\u0000The object of research is a system of informing website users using natural language. A software product has been developed, which is an information system for applicants.\u0000The dynamic JavaScript programming language combined with the Node.js code execution environment and the Telegraf library was chosen to create the chatbot. The Heroku cloud platform with an integrated Heroku PostgreSQL database became the server for the operation of the chatbot. The system is implemented using the @BotFather Telegram service, which makes it possible to integrate it into any web resource. The stages of chatbot development are highlighted with examples of information, linguistic, and technical support. An analysis of the compliance of the developed chatbot with regard to the criteria of informativeness, multimodality, emotionality, productivity, and interactivity was carried out. The structure of the information content of the chatbot, which includes a set of modules, has been developed. A test version of the chatbot has been designed, tested, and integrated into the website of the Department of Applied Linguistics, which will continue to be tested and improved in 2023–2024.\u0000Practical significance: the structure of information content and the method of developing a chatbot could be used to develop authentic systems for informing applicants in institutions of higher education","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"111 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140422454","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}

{"title":"Construction of systemic interaction between tools of remote monitoring of the technical condition and operation modes of a truck vehicle","authors":"Igor Gritsuk, I.V. Khudiakov, M. Volodarets, D. Pohorletskyi, Nadiia Pohorletska, Y. Ukrainskyi, Igor Petrov, Pavlo Nosov, Askar Tazhenov, Mikhaylo Litvinov","doi":"10.15587/1729-4061.2024.298843","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.298843","url":null,"abstract":"Parameters of the technical condition of transportation means in modern transport-logistics and infrastructure systems are an integral element of their communication support. This is enabled by the use of remote information monitoring technologies in control processes. The object of this study is the processes of vehicle remote monitoring in terms of determining the technical condition. The work addressed the task of improving the process of vehicle technical operation through the construction of a model of the remote monitoring system of its technical condition. A remote version of the information-analytical monitoring system was implemented. The work considers the system interaction of the means of remote monitoring of the state of a vehicle to ensure control under the operating conditions of the driver's work and rest modes. Road, transport, climatic conditions, etc. were taken into account. Considering these features, an information and analytical model of the system for remote monitoring of vehicle condition was built. Features of the subject area of the system are described using a DFD diagram. A structured information model of the information-communication system has been constructed, which has the ability to actually provide vehicle remote monitoring, the driver's work and rest modes, and his/her physical condition. The results, subject to the use of the V2I information model in the field of transport, allow remote monitoring of the vehicle technical condition. Specifically, to analyze the influence of changes in the physical condition and modes of work and rest of drivers on changes in the vehicle operating parameters","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140422829","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}

{"title":"Determining the influence of sandwich-type components on the load of a hatch cover in a universal open wagon","authors":"A. Lovska, V. Nerubatskyi, O. Plakhtii, S. Myamlin","doi":"10.15587/1729-4061.2024.296620","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.296620","url":null,"abstract":"The object of the study reported here is the processes of occurrence, perception, and redistribution of loads in the improved structure of the hatch cover in a universal open wagon.\u0000In order to reduce the load on the cover of an open wagon hatch, and, accordingly, to improve its strength, it is proposed to improve its design by introducing sandwich components. The thickness of the sheets that form the hatch cover has been determined. The dynamic loading of the hatch cover in the vertical plane was studied. It was found that the accelerations acting on the hatch cover with the proposed improvement are almost 20 % lower than those acting on the typical structure. The basic strength indicators of the hatch cover under the operational modes of its load have been determined. The results of the calculation showed that the maximum stresses in the hatch cover are 22 % lower than permissible ones. In addition, within the framework of the study, the main indicators of the dynamics of the open wagon equipped with the proposed structure of hatch covers were determined. The movement of the open wagon under the condition of movement in an empty state is rated as \"good\". At the same time, the maximum accelerations in the center of mass of the supporting structure of an open wagon were 4.6 m/s2, and the coefficient of vertical dynamics was about 0.6.\u0000Special features of the results within the framework of this study are that the proposed improvement of the hatch cover helps improve its strength by reducing the dynamic load, and not by strengthening the structure.\u0000The scope of practical application of the results is the engineering industry, in particular, railroad transport. The conditions for the practical use of the research results are the use of energy-absorbing material in the sandwich-type components that form the hatch cover.\u0000The study reported here could contribute to devising recommendations for the construction of components in the structures of modern freight cars, thereby reducing the costs of maintaining them in operation, as well as increasing the profitability of railroad transportation","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"3 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140423083","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}

{"title":"Identifying the influence of split tensile strength to crack width of high-strength reinforced concrete beam with polypropylene fiber from medical mask waste","authors":"Diana Ningrum, A. Soehardjono, H. Suseno, Ari Wibowo","doi":"10.15587/1729-4061.2024.298842","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.298842","url":null,"abstract":"Cracks in concrete structures due to tensile weakness can be repaired by using fiber concrete, including medical mask waste as an additive in high-strength concrete mixes. This research the influence of polypropylene fiber from medical mask waste on the mechanical characteristics, flexural behavior, and crack width of high-strength reinforced concrete (RC) beams. The initial stage involved examining the properties of the concrete constituent materials. The testing process was based on a high-strength concrete mix design using the Aitchin method mix design sheet. Compressive strength and split tensile strength were tested at fiber content (0 %, 0.15 %, 0.20 %, and 0.25 %). The three-point flexural testing procedure was carried out at 28 days on 1200×100×150 (mm) RC beams. The use of LVDT, strain gauge, and other measuring devices supported the acquisition of the required data. The results showed that the split tensile strength reached the optimum value of 66.19 MPa at 0.24 % fiber content. Polypropylene fiber from medical mask waste in RC beams showed a positive impact on reducing crack width at increased split tensile strength. Waste mask fiber content of 0.15 %, 0.20 % and 0.25 % gave stable and better results compared to 0 % content (no fiber). With high steel stress (fs), and high strain, it offers the potential to improve the mechanical properties of high-strength concrete, thereby reducing the width of cracks that occur. This improves the tensile weakness of the concrete. The effect of split tensile strength on the crack width (w) of beams with the formula approach: wexp=3.74ftf-1.513, wan=0.187ftf-0.022 shows that the experimental results have a significant effect on decreasing the crack width that occurs in high-strength RC beams, thereby improving the quality of concrete","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"132 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140423812","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}

{"title":"Ensuring uniformity of strength of fine-grained concrete based on modified composite cement","authors":"Aleхsandra Shіshkina, Andriy Domnichev","doi":"10.15587/1729-4061.2024.296898","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.296898","url":null,"abstract":"Insufficient determination of the effect of surface-active substances introduced in extremely low concentrations on the formation of the stability of the properties of fine-grained concrete based on composite Portland cements determined the feasibility of conducting research in this area. The studies investigated the influence of the modification of composite cement with water activated by the use of the hydrophilic hydration mechanism. It has been proven that these factors include the type and amount of applied water nano modifiers. The analysis of the study results confirmed that the introduction of water activated by the mechanism of hydrophilic hydration into concrete in extremely small doses significantly increases the rate of formation of concrete strength and reduces the coefficient of its variation. Owing to this, the strength of the resulting modified fine-grained concrete based on composite cement at the age of 3 days exceeds the strength of the similar concrete without additives by 300 %, and at the age of 27 days – by 25 %. At the same time, the coefficient of variation of strength has a minimum value at the optimal amount of nano additive – water modifier. This allows us to assert the effectiveness of the revealed mechanism of modification of composite cement. Thus, there are reasons to assert the possibility of targeted regulation of the processes of formation of a strong homogeneous structure of fine-grained concrete based on composite cement by using water activated by the mechanism of hydrophilic hydration","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"509 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140417520","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}

{"title":"Implementation of financial control tools in the adaptive management of enterprise financial security","authors":"P. Pronoza, T. Kuzenko, N. Sablina","doi":"10.15587/1729-4061.2024.294765","DOIUrl":"https://doi.org/10.15587/1729-4061.2024.294765","url":null,"abstract":"The results reported here proved the necessity of introducing financial controlling tools into the system of adaptive management of the company's financial security, which is inextricably linked with technology transfer. The object of the study is the movement of technology with the application of any information on ensuring the implementation of financial controlling tools in the process of managing the financial security of enterprises. We analyzed theoretical approaches to adaptive management of financial security of enterprises. The principles, functions, and types of financial controlling were considered. The expediency of researching the financial security of enterprises using financial controlling as a functional system of adaptive management of deviations has been proven. A systematic approach was used to study scientific approaches to adaptive management of financial security based on financial controlling. Considerable attention was paid to the analysis of the functions and tasks of financial controlling under today's unstable conditions of the economic development of enterprises. Using the method of system analysis, theoretical and methodological approaches to understanding the essence of financial controlling in the adaptive management of financial security of enterprises were evaluated. Peculiarities in the scientific approaches of various scientists regarding the essence of the financial security of enterprises have been revealed. The role and significance of adaptive management of the financial security of enterprises with the help of a modern toolkit of financial controlling, which consists of contractual obligations that make it possible to ensure an effective mechanism for making managerial decisions regarding the enterprise and its counterparties or other financial institutions, is revealed. The extended capabilities of the financial controlling toolkit are useful for analysts and enterprise managers to justify and improve the quality of adaptive management of the enterprise's financial security in modern conditions of technology transfer","PeriodicalId":11433,"journal":{"name":"Eastern-European Journal of Enterprise Technologies","volume":"33 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140418462","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}