2022

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Advantages of using hydraulic equipment of modular mounting in the modernization of machine hydrosystems
(Національний технічний університет "Харківський політехнічний інститут", 2022) Fatieieva, N. M.; Fatyeyev, O. M.; Ponomarov, Vladyslav
With each passing year, automation schemes that use hydraulics are becoming more and more complex. With the large number of hydraulic devices in the scheme, replacing threaded connections with other methods of mounting becomes very important. The analysis of building and mounting of hydraulic drives and hydraulic units on the example of metal-cutting machines, namely: round saw and turret lathe. The analysis shows that the optimal variant of pipeless mounting of hydraulic drives is mounting with the use of modular and butt hydraulic equipment. The main advantages of modular mounting are: reducing the number of pipelines and their connections; increasing drive rigidity, reducing noise; compactness, small size and weight; reducing labor costs and time for design and manufacture of the drive; convenience of operation, the ability to quickly reconfigure the drive, replace the failed unit without disassembly of the hydraulic drive; unification of mounting plates and hydraulic panels; increasing their seriality. In addition, with this type of mounting, there is always a constant distance between the individual devices and regulating bodies of different apparatuses that make up a typical element of a hydraulic system (its structural contour). This makes it possible to determine in advance the characteristics, properties and "behavior" not of individual hydraulic apparatuses included in the hydraulic system of the machine drive, but of groups of apparatuses that make up typical modular units. We have an opportunity to judge the characteristics of the hydraulic drive of the machine as a whole already at the stage of its design by predetermined characteristics of typical elements (modular units) included in the hydraulic system of the machine, which will significantly reduce the time for designing, debugging and launching the drive in production. The group of metalworking equipment, in which the hydraulic drive on the basis of modular and butt hydraulic equipment is easily performed, includes: turning group machines; drilling and boring machines; grinding group machines; broaching machines; cutting machines, milling machines and other special machines. Justified selection of the nomenclature of normalized hydrostations, modular and butt hydraulic apparatuses and other unified elements can solve the problem of creating up to 70–75 % of the manufactured hydraulic drives completely based on unified units.
The approach and the software tool to calculate semantic quality measures of business process models
(Національний технічний університет "Харківський політехнічний інститут", 2022) Kopp, Andrii Mykhailovych; Orlovskyi, Dmytro Leonidovych
Business process models are essential business process management artifacts that help describe visually ongoing business activities to facilitate communication between information technology and business stakeholders. Business process models are used to find inefficient spots within described workflows and resolve detected shortcomings by automation via configurable software solutions or unified workflow engines. However, this is impossible when using syntactically or semantically poor business process models. It is the same as building a house using the blueprint with windows on the floor and typos in text labels. Therefore, it is extremely important to keep created business process models clear and relevant to the actual workflows they describe. Hence, in this paper, we propose the approach and the software tool to calculate semantic quality measures of business process models. The proposed approach uses a special procedure to extract the modeling domain statements using natural language processing techniques. According to the proposed approach, the initial textual descriptions of business process models should be tokenized. Then obtained tokens should be turned to the lower case style and cleansed to remove non-alphabetic tokens and stop words. Finally, the remaining tokens should be stemmed and the existing duplicates should be removed. The same procedure is then repeated for text labels attached to the business process model activities. Then, tokens present in the result of textual description’s processing but missing in the result of labels’ processing are considered incomplete (i.e. incorrect in the modeling domain). Similarly, tokens present in the result of labels’ processing but missing in the result of textual description’s processing are considered invalid (i.e. irrelevant to the modeling domain). Therefore, respective semantic quality measures can be calculated. The software tool is created using the Python programming language because of its powerful natural language processing packages.
Assessing the informativeness of the controlled parameters in the task of identyfing the state of the system
(Національний технічний університет "Харківський політехнічний інститут", 2022) Raskin, Lev Hryhorovych; Sukhomlyn, Larysa Vadymivna; Sokolov, Dmytro Dmytrovych; Domochka, Lidiia Vladyslavivna
The effectiveness of solving the problem of identifying the system state significantly depends on the number of controlled parameters and the degree of their informativeness. The traditional method for assessing the informativeness of these parameters is based on the measure of distance between the probability distributions of the values of the controlled parameter for different states of the system proposed by Kullback. The shortcomings of Kullback measure have been revealed. Firstly, the value of this measure is not normalised and is not limited from above. Secondly, this measure is asymmetric, i.e. its numerical value depends on the way its components enter the calculation ratio. The method for calculating the informativeness criterion proposed in this paper takes into account the uncertainty that arises due to the fuzzy description of the boundaries of the areas of possible values of the controlled parameters for each of the possible states of the system. An important enhancement of the known methods for assessing the informativeness of the controlled parameters is to take into account the real existing inaccuracy in estimating the values of the results of measuring these parameters themselves. These circumstances determine the subject and purpose of the study that is the development of a method for calculating the distance between the distributions of fuzzy values of the controlled parameter, free from the shortcomings of the Kullback measure. To calculate the measure of the distance between the distributions of the values of the controlled parameter under conditions of uncertainty of the initial data, described in terms of fuzzy mathematics, a symmetric criterion is proposed, which is easily calculated. Examples of the criterion calculation are given. The possibilities of increasing the level of informativeness of the criterion using analytical descriptions of membership functions of fuzzy values of the controlled parameter for different states of the system are considered.
Black and white-box unit testing for web applications
(Національний технічний університет "Харківський політехнічний інститут", 2022) Golіan, Nataliіa Viktorivna; Golіan, Vira Volodymyrivna; Afanasieva, Iryna Vitayivna
The types of the testing methods were analyzed from the side of development. If changes are made to the code, even minor ones, bugs can appear anywhere in the system. The cost of fixing bugs increases with the time they are discovered. Using effective web testing can prevent unexpected costs. Modern web applications are indeed a place where all the type of the testing is vital for the high-quality product. At the moment, traditional front and back office applications are increasingly moving from desktop computers to web interfaces, so testing web applications is becoming extremely relevant. Thus, learning what to automate and how is an important component of successful web application testing. Web application testing is a software practice that is designed to ensure quality by verifying that the functionality of a particular web application works correctly or according to fixed requirements. Web testing makes it possible to find bugs at any point in time, before release or on a daily basis. On the one hand there are wide range of tools that could be used to pursue this goal by means of using best decisions present for now but on the other hand there are essential advantages and disadvantages present in these tools, which are all in the approach to it, so there are always cons and pros of using one or another. For now, despite on having the ability to test using both black and white box testing it looks like the second one is not the best choice. There are several points on each board for both of them, but black box approach that is being represented with react testing library is more successful and efficient way to cover and application with high- and low-level tests, that could be easily maintained and understood. But white box testing is now the most used decision due to the historic development of the industry. So, it also has some great features and could be chosen to be used on the project, but it should be precise choice with the understanding of all the consequences standing behind.
Bottomhole formation zone restoration mechanisms and methods
(Національний технічний університет "Харківський політехнічний інститут", 2022) Zezekalo, Ivan Havrylovych; Bukhkalo, Svetlana Ivanovna; Ivanytska, Iryna Oleksandrivna; Aheicheva, Oleksandra Oleksandrivna
The importance of the choice of well exploitation methods is analyzed. Mechanical methods applicable in carbonate reservoirs are discussed. To maintain the efficiency of field development, it is important to maintain the productivity of wells at the planned level throughout the entire production period by increasing their productivity. Productivity increase, skin effect reduction is achieved with the help of acid treatment, the main principle of which is rock dissolution to form a man-made network of microchannels in the bottomhole formation zone, which allows maintaining the recovery rate at the planned level for a long period of time. Forecasting the flow rate of wells in fields with reserves of high-viscosity oil is one of the most difficult tasks in the development of oil fields. Acid treatments quality increasing through new working agent’s usage and improving the technology analysis is performed. Acidizing a reservoir is inherently dual in nature in terms of the desired effect: while in some conditions it has a positive effect, in other conditions it may not be applicable at all.
Comparison of synchronous generators for autonomous gasoline installation system
(Національний технічний університет "Харківський політехнічний інститут", 2022) Chumaсk, Vadim Vladimirovich; Kovalenko, Mykhaylo; Tkachuk, Ihor; Kovalenko, Iryna Yakivna
There are many power plants like thermal, solar, hydro, nuclear etc. but there are some disadvantage of it like CO2 emission pollution, problem of global warming requirement of fuels cost etc. To avoid such factors we developed system is biomass power plant to meet the demands of electricity and envi-ronment concern day by day price of fuels that fact to which motivate to use renewable energy. Biomass is renewable in nature, carbon neutral and has the potential to provide large productive employment in rural areas. It is considered as one of the promising sources for generation of power / energy using commercially available thermal and biological conversion technologies. The fossil fuels are depleting very fast, it is very important to replace fossil fuels with best alternative fuel modes which will be available for requirement in abundance at the same time if it is ready at one’s disposal is a eminent balance to the environment. The sanctification for this need is the bio mass power plant; on finding the major advantage of bio mass power plant is the fuel which is agricultural waste (rice husk, wood, etc.) segregation available in unnumbered tons around the world. It is very important to utilize this in the context of energy. It is also found that the sulphur content in the biomass is very less when compared with coal. The wood fuels contains very little ash (-1% or less), so increasing the ratio of wood in biomass coal blends can reduce the amount of ash that must be disposed. In biomass power plants, wood waste or other waste is burned to produce steam that runs a turbine to make electricity, or that provides heat to industries and homes. Fortunately, new technologies including pollution controls and combustion engineering have advanced to the point that any emissions from burning biomass in industrial facilities are generally less than emissions produced when using fossil fuels (coal, natural gas, oil), biomass is burned in a combustor or furnace to generate hot gas, which is fed into a boiler to generate steam, which is expanded through a steam turbine or steam engine to produce mechanical or electrical energy. In this paper were performed comparison of traditional synchronous generator with electromagnetic excitation and permanent magnet generator for autonomous gasoline installation system.
Computer ethics training in higher educational institutions as one of the factofs of forming the social responsibility of future specialists
(Національний технічний університет "Харківський політехнічний інститут", 2022) Lapuzina, Olena M.
The given article encompasses problems of computer ethics role in the technical specialists preparing process. The attention is focused on an urgency and practical significance of this problem in modern conditions of computer technique development. The article examines the special role of higher education in creating computer ethics standards, analyzes the study of modern forms of information ethics, which is extremely relevant in the conditions of global digitalization, as well as at the justification of the need for its study in institutions of higher education. The skills and abilities of technical students and students who study in the field of informatics and plan to be future software developers responsible for making decisions about various types of technology development are considered in the article. A conclusion was made about the need to introduce a course on the ethics of the global information space, that is, computer ethics, into the education of students, along with the creation and implementation of codes of scientific information ethics for scientists and teachers of modern universities.
Computer modeling of the stress state and reliability assessment of bolted connections of the rotor and runner of kaplan turbines
(Національний технічний університет "Харківський політехнічний інститут", 2022) Vodka, Oleksii O.; Viazovychenko, Y. A.; Larin, Oleksiy Oleksandrovych; Potopalska, K. E.
This study presents a comprehensive theoretical assessment of the deformed state and stresses in the bolted joints of the runner and shaft of the hydroturbine. The investigation is motivated by the need to understand the structural behavior of these critical components under varying operational conditions. The primary purpose of this research is to evaluate the theoretical aspects of the bolted joints hydro-turbine, emphasizing the impact of tightening technology on the deformed state and stress distribution. A comprehensive review of literature, drawings, material properties, and acting loads of the bolted connection for turbines is conducted, estimating loads during normal operation and load rejection. A detailed nonlinear finite element model of the bolted joint is built, considering a 3D bolt model and runner fragments. The model incorporates nonlinear effects such as contact interaction and plasticity of the material during deformation. A methodology for modeling bolted joint tightening technology is developed, allowing estimation of bolt pre-operation stress and deformed states. Error estimation and model validation are performed through a comparative analysis of models with different meshes. Stresses arising at different tightening levels are determined, showcasing the non-linear effect on bolt stresses. The study reveals that the maximum numerical error in stress estimation does not exceed 5.2%. Stresses at different tightening levels demonstrate a nonlinear response, with significant reductions and increases corresponding to tightening deviations. Estimated stresses in the main operating loading cycle provide insights into the amplitude and average stress values during normal operation and load rejection. The study estimates a significant number of cycles before the initiation of a fatigue crack, equivalent to approximately 142 years of operation.
Construction of a multivariate polynomial given by a redundant description in stochastic and deterministic formulations using an active experiment
(Національний технічний університет "Харківський політехнічний інститут", 2022) Pavlov, Alexander Anatolievich; Holovchenko, Maxim Nikolaevich; Drozd, Valeria Valerievna
We present the methods for constructing a multivariate polynomial given by a redundant representation based on the results of a limited active experiment. We solve the problem in two formulations. The first is the problem of constructing a multivariate polynomial regression given by a redundant representation based on the results of a limited active experiment. The solution method is based on the previous results of Professor A. A. Pavlov and his students showing the fundamental possibility of reducing this problem to the sequential construction of univariate polynomial regressions and solving the corresponding nondegenerate systems of linear equations. There are two modifications of this method. The second modification is based on proving for an arbitrary limited active experiment the possibility of using only one set of normalized orthogonal polynomials of Forsythe. The second formulation refers to the solution of this problem for a particular but sufficient from the practical point of view case when an unknown implementation of a random variable is not added to the initial measurement results during an active experiment. This method is a modification of the solution method for the multivariate polynomial regression problem. Also, we used the main results of the general theory (which reduces the multivariate polynomial regression problem solving to the sequential construction of univariate polynomial regressions and solution of corresponding nondegenerate systems of linear equations) to consider and strictly substantiate fairly wide from the practical point of view particular cases leading to estimating the coefficients at nonlinear terms of the multivariate polynomial regression as a solution of linear equations with a single variable.
Construction of the software and technical complex of control basic parameters of reactor installation
(Національний технічний університет "Харківський політехнічний інститут", 2022) Koba, Kostyantyn; Lys, Stepan; Kravets, Taras; Yurasova, Oksana; Galyanchuk, Igor
The main problem associated with the operation of nuclear power plants is the problem of correct and timely diagnosis of failure or violation. The mistakes of technologists can lead to severe damage to nuclear power plants, or simply to a reduction in the utilization rate of installed capacity. The personnel make the main mistakes in the conditions of time shortage and being in a stressful situation during the development of an accident, when assessing changes in emergency parameters is not always possible, which leads to incorrect diagnosis of initial events (IE). Any IE leads to the deviation of the monitored parameters from normal values (values that are inherent to normal operation). The operator-technologist needs as soon as possible to determine the parameter (or parameters) for which the change occurs and, by performing a certain sequence of actions, bring their values to the norm. For information support of the operator-technologist is the information computing system (ICS). In the ICS, it is possible to control all parameters affecting the safe operation of the equipment, for each of which there are certain values, the deviation from which may lead to an accident. The paper considers the issues of the need to separate the measured parameters of NPP into separate groups that uniquely characterize the state of the critical security features. In particular, the necessity of consideration as the most important mass parameter of the primary coolant is shown. The issues of level measurement problems in the pressure compensator are discussed as the most important from the point of view of determining the mass of the primary coolant. Methods are proposed for determining the operability of sensors, the method of calculating a reliable level in the volume compensator. Estimates of the computational efficiency of the proposed methods are given.
Continuous Integration for a development process of the information technology of remote monitoring and control
(Національний технічний університет "Харківський політехнічний інститут", 2022) Mnushka, Oksana; Leonov, Serhii; Savchenko, Volodymyr
The current state of using CI/CD in commercial and open-source projects is analyzed. CI/CD pipelines are shown to be essential to the modern software development process, where they are used to configure workflows. Centralized and distributed approaches to building a software source code version control system are analyzed. For the web-oriented SCADA project, the choice and use of the version control system are justified. We provide concrete examples of using CI/CD that will allow ordinary developers, not DevOps specialists, to take the first steps to configure workflows for their projects and provide basic steps for configuring task execution using the example of the build and test phase of the source code of a real project that uses several programming languages.
Critique of the sense in W. V. O. Quine's philosophy
(Національний технічний університет "Харківський політехнічний інститут", 2022) Hlushchenko, E. Vyacheslavovych
The article is devoted to the studies the problems of interpretations and representations of the concept of “sense” in logical semantics , which has been analyzed by the outstanding American philosopher and mathematician of the middle and a second half of the XX century – Willard Van Orman Quine, who has snooped far enough into the presented problem in numerous of his works, mainly, his “Word and Object” and “From a Logical Point of View”. The central critical theories of understanding Quine’s thought of the sense is seen at another angle, that is, as a main concept that gets some responds of the philosophers in post-analytical philosophy tradition, along with it is reviewed as a broadly interpreted concept. Additionally, modes of such critique can be found as in some classic works of the philosophers like D. Davidson or M. Dummett, or as of such modern analytical philosophers as: M. Baghramian, L. Komacha, P. Livingston, J. Smith, and others. About this material few modern works and Quine's as well have been particularly researched, and of our opinion, the movement of such explanation of the sense problem in Quine's works keeps coming to be emphasized in today's philosophy. We result this work on that the critique of the sense in Quine's works hadn't been done the way perfectly: not enough enlightened though. Hereby we claim to keep monitoring and not to stop studying of the metaphysical context of works and cultural as well. The better that point becomes to get larger area to study the more successful the research is expected. That way of criticizing half-metaphysical concepts aimed as a method, on the one hand, is required for a more advanced investigations of the proliferation in post-analytical philosophy works, and, on the other hand, as a reason of ideas and views separation, which are not relevant to the traditional analytic philosophy, is taken and viewed using examples. New critique of few aspects of Quine's philosophy are necessary to get closer to the as the philosopher's ideas to the newest ideas for the development of the science as well. Many key and well points can be gotten from the way to analyze the works. Interpretations of meaning of the concept of sense in the different papers of analytical philosophers is supposed to change the key direction of the considered this topic.
Design characteristics of the horizontal steam generator PGV-1000
(Національний технічний університет "Харківський політехнічний інститут", 2022) Yefimov, Olexander Vyacheslavovich; Tiutiunyk, Larysa Ivanivna; Harkusha, Tetyana Anatoliivna; Yesypenko, Tetyana Oleksiivna; Motovilnik, Anastasiia Vadimovna
The materials of the article consider the design characteristics of horizontal steam generators PGV-1000 for WWER NPPs. The NPP steam generator, in particular the PGV-1000 steam generator, is a specific heat exchange unit. This unit, together with a nuclear reactor and a steam turbine, is one of the main equipment of multi-circuit (double-circuit) steam turbine NPPs. The steam generator produces working steam using heat dissipated from the reactor core by the cooling medium and sent to the heat exchange surface of the steam generator. NPP steam generators, connecting the contours of the coolant and the working substance, equally belong to each of them. The heat-absorbing medium in the steam generator is the working substance (water, steam). PGV-1000 type NPP steam generators with pressurized water reactors produce dry saturated steam. The requirement to maintain high purity of the coolant is due to the heat transfer surfaces of such steam generators made of austenitic stainless steel with electropolished surfaces. WWER reactors do not allow the coolant to boil in the core, so the temperature of the coolant at the outlet of the reactor (at the inlet to the steam generator) is always lower than the saturation temperature corresponding to the water pressure in the coolant circuit. Underheating of the coolant to the saturation temperature (approximately 25 ÷ 30 °С) guarantees the exclusion of vaporization even in the most loaded reactor channels. The design characteristics of modern horizontal steam generators such as PGV-1000 of various modifications provide high technical and economic performance of NPP units with WWER-1000 and high maintainability, which allows to extend the service life of domestic NPPs.
Development of horizontal bulb hydroturbines for high heads with a wide range of reliable operation modes
(Національний технічний університет "Харківський політехнічний інститут", 2022) Krupa, Y. S.
The issues and directions for improving the energy-cavitation and operational performance of hydro turbine equipment of hydroelectric power plants are considered. The paper analyzes in detail the directions for improving the main indicators characterizing the energy and operational advantages of horizontal hydro turbines. Straight-axis Kaplan hydraulic turbines with a horizontal axis of rotation of the hydraulic unit have incomparable advantages compared to hydraulic turbines with water supply using a spiral case, in terms of higher throughput and a wider range of operation. The practice of hydraulic turbine construction has determined the range of heads for which different types of hydraulic turbines are used. The use of horizontal direct flow hydraulic turbines for heads of more than 40 meters encounters a number of problems of a hydrodynamic nature, strength, and reliable operation. The paper analyzes the advantages of direct-flow bulb hydro turbines and the possibility of using them for high heads. New design solutions are considered, for which Ukrainian patents have been obtained, allowing the use of horizontal bulb hydraulic units for higher heads (up to 300 meters) and at the same time obtaining a wider operating area not only in terms of flow rates, but also in terms of heads. The use of twin bulb hydraulic units will significantly expand the operational ranges of highly efficient and reliable operation of horizontal bulb hydraulic turbines at flow rates (power) that allow them to successfully operate at variable peak loads of daily regulation. Based on the analysis of the working process of various horizontal and diagonal turbines, the analysis of their universal characteristics, scientifically based proposals was developed for the nomenclature of twin bulb hydraulic units. The design of a horizontal hydraulic turbine using inlet nozzle channels is presented. The use of nozzle diaphragms as elements that create the angular momentum necessary for optimal operation of the hydraulic turbine makes it possible to use bulb direct-flow hydro units for high heads (80–100 meters).
Development of public administration with help of social technologies
(Національний технічний університет "Харківський політехнічний інститут", 2022) Hren, L. M.; Grybko, Olga
The article considers the importance of social technologies that affect, in fact, all aspects of social phenomena, established their cumulative effect, which is expressed in the constant enrichment of social experience, implementation of effective activities (including management), increasing knowledge, skills, strategies, reusability algorithms for solving typical social problems. A number of reasons have been identified for which social technologies in public administration are becoming increasingly important, namely: 1) in the context of social development, under the influence of globalization, digitalization of public life and immanent network socio-economic links social management; 2) the socio-technological tools are growing rapidly, which allows us to hope today for its organic integration into the network of both social and information technologies of any type organizations; 3) the spread of modern information and communication technologies with their ability to influence the mass public consciousness. The results of decentralization reform in Ukraine are considered as an example of strategic changes in the organization of social life and the basis for the use of social technologies in local community management. The conclusion was made about actualization of social technologies' application in public administration, caused by: 1) orientation on optimum forms of social system existence, its efficiency, rationality; 2) the need to create dynamic social systems that are characterized by balanced relations within the system itself and the harmonization of relations with other systems; 3) the need to implement social creativity; 4) social necessity in the planned, projected and managed development of social systems and processes; 5) social necessity in overcoming the spontaneous development of social processes and ensuring their orientation in the field of meeting social needs; 6) the public need for purposeful change and development of social systems and social processes; 7) the social need to reduce the level of social disorder and instability; 8) necessity to use digital instruments in managing social life; 9) the social need to implement the constructive nature of social processes.
Development of the component base of unified assenbly and parts of installation clamping devices
(Національний технічний університет "Харківський політехнічний інститут", 2022) Yakovenko, Ihor Eduardovich; Permyakov, Alexandr Anatolievich; Kharchenko, Oleksandr Sergvyovich
The issues of unification of units and elements of special equipment were further developed in the work. Issues of a theoretical approach to the creation of an element base of unified assemblies and parts for existing layout schemes for mounting and clamping devices of equipment built on the principles of aggregation are considered. in order to subsequently minimize the cost of design and production. The authors propose a two-stage methodology for unifying fixture elements in order to create a reference and regulatory framework for such elements. At the first stage, based on the analysis of the functional purpose of the structural elements of various layout schemes of devices, a list of parts is established, the unification of which is possible and expedient. At the second stage, based on the strength analysis of the selected elements and the analysis of statistical information on the geometric parameters of the installed workpieces for various layout schemes of fixtures, the number of standard sizes and geometric parameters of these parts are determined. This approach allows you to create a constantly updated and edited database of unified fixture elements, which can be used in the process of computer-aided design.
Development of universal high-strength magnesium aluminosilicate glass-ceramic materials for armor protection
(Національний технічний університет "Харківський політехнічний інститут", 2022) Savvova, Oksana Viktorivna; Tymofieiev, Vadym Dmytrovych; Voronov, Hennadii Kostiantynovych; Fesenko, Oleksii Igorovych
The necessity of creating innovative protective structures for armoring machinery and equipment is analyzed. A comparative analysis of high-strength materials used for local and individual body armor has been carried out. The relevance of the development of domestic universal armored materials that combine high strength properties and radio transparency based on lightweight technological magnesium aluminosilicate glass-ceramic materials with high performance properties at the level of world analogues has been determined. Were formulated the purpose and tasks of the work, which consist in: analysis of the current state of development of glass-ceramic materials for armor protection; development of magnesium-aluminosilicate glass-ceramic materials with high armor resistance, impact resistance and radio transparency; investigation of the operational properties of the developed glass-ceramic materials and their armor resistance; assessment of the competitiveness of the developed glass-ceramic materials. A set of requirements for a glass matrix for obtaining protective glass-ceramic materials has been formulated. Compositions and technological parameters for the production of glass-ceramic materials under the conditions of two-stage low-temperature heat treatment have been developed. The study of the electrical properties of experimental glass-ceramic materials made it possible to establish the possibility of effective functioning of on-board wireless communication systems when using the developed materials as elements of armor protection. It was found that the developed glass-ceramic materials are characterized by high operational properties (KCU = 5.8 kJ/m²; HV = 10.4 GPa; K1C = 8.5 MPa∙m⅟ ²) and armor resistance STANAG 4569 (level 2). The competitiveness of the developed glass-ceramic materials based on mullite is analyzed. It has been established that a significant increase in fracture toughness and a decrease in the density of the developed material when comparing properties with a similar armor element (corundum based plate) will significantly reduce the weight of the armor elements by ≈1.4 times and its cost by five times, while maintaining its protective properties.
Enrichment of the products of fat-and-oil and biotechnology industries by antioxidants and preservatives of powders from barry raw materials
(Національний технічний університет "Харківський політехнічний інститут", 2022) Ananieva, Valeriia Victorivna; Varankina, Olexandra Olexandrivna; Ovsiannikova, Tetyana Oleksandrivna; Zhirnova, Svitlana Victorivna
It was found in investigation of amount of polyphenolic substances in samples of mixes with different contents of grape skin and mountain ash powders that varying the ratios of the mass fractions of the components practically did not affect the content of quercetin, which was not less than 6.7%. Oxidated form of quercetin can influence on increase in resistance to microbiological spoil of a finished product. Inverse proportion between increasing in mass fraction of mountain ash berries powder and the sum of polyphenolic substances in terms of cyanidin-3,5-diglucoside was defined. It was shown in the study of sorbic acid content in samples of mixes of powders that content of sorbic acid increased from 0.43% to 0.54% with an increase (from 1% to 3%) in the mass fraction of mountain ash berries powder in the mixture. It was shown in the research of pectic substances content in selected samples of mixes of powders that total content of pectic substances also increased from 1.89% to 3.28% with an increase in the mass fraction of mountain ash berries powder and crude fiber values practically did not change. The conducted microbiological researches of samples of mayonnaise with 40.0% fat mass fraction and yogurt with a 2.5% fat mass fraction showed that adding of mix of grapes skin powder (2.0% by weight) and mountain ash berries powder (3.0% by weight) into the products slowed down the growth of yeast and mold.
Example of use of virtual promotion map
(Національний технічний університет "Харківський політехнічний інститут", 2022) Orekhov, Sergey Valerievich; Kopp, Andrii Mykhailovych; Orlovskyi, Dmytro Leonidovych
The paper presents an example of using new technology to solve the problem of promoting goods and services according to the 7P concept. The technology was called virtual promotion. The reason for its occurrence is a decrease in the effectiveness of the currently classical search engine optimization methodology on the Internet. The task of the latter is to bring the given corporate WEB resource to the first place in the search server’s answers to the requests of potential buyers. Virtual promotion is based on two ideas. The first is based on marketing theory when to sell a product or service, you need to build a marketing channel. The second is that a search server is an intelligent machine. Then, to get the first position, we need to teach the virtual space, which consists of Internet nodes, to activate in such a way that the number of links to the WEB page with the desired product is maximum. To implement these ideas, two objects are synthesized as part of the virtual promotion: a semantic kernel and a promotion map. A semantic kernel is a description of a product or service or a training sequence of keywords. A map is a set of nodes on the Internet, where the semantic core should be placed to attract the maximum number of buyers of the product. The map is also a variant of marketing channels on the Internet. The paper considers an example of a situation where a semantic core and a minimal map have already been created using the classical approach (search optimization). In this case, the classic approach gave an increase in the number of visits to the WEB site, but there was not a single buyer of the product for six months. That is, the classical approach improved the key performance indicator, but it did not affect the sales performance in any way. The paper demonstrates how virtual promotion forms such a modification of the map that gives a given result in a given period. At the same time, it is not enough to synthesize a new map. It is necessary to apply a special mechanism for its implementation. For this purpose, the paper shows a real task of inter-functional coordination, which makes it possible to implement a promotion map. Real data for 2021, which was used to promote the product on the Ukrainian market, is given. The introduction of the new version of the map resulted in the first two orders within the first two weeks.
Examples of information technologies for reconstruction from the data of the spectrum of some classes of random functions
(Національний технічний університет "Харківський політехнічний інститут", 2022) Prishchenko, Olga Petrivna; Cheremskaya, Nadezhda Valentinovna; Bukhkalo, Svetlana Ivanovna
It is known that a stationary random process is represented as a superposition of harmonic oscillations with real frequencies and uncorrelated amplitudes. In the study of nonstationary processes, it is natural to have increasing or declining oscillationсs. This raises the problem of constructing algorithms that would allow constructing broad classes of nonstationary processes from elementary nonstationary random processes. A natural generalization of the concept of the spectrum of a nonstationary random process is the transition from the real spectrum in the case of stationary to a complex or infinite multiple spectrum in the nonstationary case. There is also the problem of describing within the correlation theory of random processes in which the spectrum has no analogues in the case of stationary random processes, namely, the spectrum point is real, but it has infinite multiplicity for the operator image of the corresponding operator, and when the spectrum itself is complex. Reconstruction of the complex spectrum of a nonstationary random function is a very important problem in both theoretical and applied aspects. In the paper the procedure of reconstruction of random process, sequence, field from a spectrum for Gaussian random functions is developed. Compared to the stationary case, there are wider possibilities, for example, the construction of a nonstationary random process with a real spectrum, which has infinite multiplicity and which can be distributed over the entire finite segment of the real axis. The presence of such a spectrum leads, in contrast to the case of a stationary random process, to the appearance of new components in the spectral decomposition of random functions that correspond to the internal states of "strings", i. e. generated by solutions of systems of equations in partial derivatives of hyperbolic type. The paper deals with various cases of the spectrum of a non-self-adjoint operator A, namely, the case of a discrete spectrum and the case of a continuous spectrum, which is located on a finite segment of the real axis, which is the range of values of the real non-decreasing function a(x). The cases a(x) = 0, a(x) = const, a(x) = x and a(x) is a piecewise constant function are studied. The authors consider the recovery of nonstationary sequences for different cases of the spectrum of a non-self-adjoint operator A promising since spectral decompositions are a superposition of discrete or continuous internal states of oscillators with complex frequencies and uncorrelated amplitudes and therefore have deep physical meaning.