2018

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18-пульсный выпрямитель с электронным сдвигом фаз и согласующим автотрансформатором
(НТУ "ХПИ", 2018) Сокол, Евгений Иванович; Замаруев, Владимир Васильевич; Бутова, Ольга Анатольевна; Войтович, Юрий Сергеевич
Для снижения гармонических искажений входного тока, применяются многопульсныевыпрямители, требующие наличия фазосдвигающих трансформаторов либо автотрансформаторов. Исключение электромагнитных фазосдвигающих устройств при сохранении малых гармонических искажений входного тока и получении близкого к единице коэффициента мощности, возможно при использовании электронного сдвига фаз. В статье рассмотрены принципы построения многопульсных выпрямителей с электронным сдвиг фаз, который осуществляется средствами самого выпрямителя: введением положительных и отрицательных углов управления. В этом случае, для выравнивания токов отдельных выпрямителей может применяться как повышение напряжения на входе выпрямителей, работающих с большими углами управления, так и понижение входного или выходного напряжения выпрямителей, работающих с меньшими углами управления. Проведено сравнение выпрямителей с использованием повышающих и понижающих автотрансформаторов. Получены данные об установленной мощности автотрансформаторов, мощности потерь. Приведены результаты теплофизического моделирования.
85 річниці з дня утворення кафедри інтегрованих технологій, процесів та апаратів присвячується
(НТУ "ХПІ", 2018) Ведь, Валерій Євгенович
Algorithms and software solutions for SQL injection vulnerability testing in web applications
(НТУ "ХПІ", 2018) Arslan, Berk; Gamzayev, R. O.; Karaçuha, Ertuğrul; Tkachuk, M. V.
Software security gains importance day by day and developers try to secure web applications as much as possible to protect confidentiality, integrity and availability that are described in the fundamental security model so-called CIA triad. SQL injection vulnerability which can violate the confidentiality and integrity principles of the CIA triad is reviewed, and SQL injection attack execution and protection techniques are explained. The common frameworks’ solutions against SQL injection vulnerability were compared, and this comparison shown the most used techniques in this domain. Error-based and time-based detection algorithms for SQL injection’s identification are developed to create a vulnerability scanner that can detect SQL attacks which cause vulnerability in web applications, and these algorithms are represented in form of UML-activity diagrams. In order to discover all possible links and forms to perform SQL injection vulnerability tests in the entire website, a web crawler is needed. Breadth-First Search (BFS) algorithm for developing the web crawler is proposed, and the appropriate pseudo code and activity diagram are provided. Besides, Common Vulnerability Scoring System (CVSS) that is used to measure severity score of attacks that can violate CIA triad principles is reviewed. Qualitative severity score rating scale of CVSS is explained. An example of CVSS calculation is represented. Necessary components of a vulnerability scanner are explained. A vulnerability scanner prototype is developed using explained algorithms. Process results of this vulnerability scanner’s usage for real web applications are represented. Conclusions are made, and goals of future work are defined.
Analysis of the Markowitz’s and Tobin’s models for securities portfolio construction
(НТУ "ХПИ", 2018) Vietrova, Halyna Viktorivna; Huzhva, Viktor Oleksiiovych
The conclusions about the strata of society, various parties are supported by, have been made. The question arises of revising and improving the ways of forming the investment portfolio, since the degree of influence of macroeconomic indicators on the stock market behavior changes. The stock market is one of the key elements of the financial system of any state. The essence of the securities portfolio, the main task and the main objective of portfolio investment, the nature and methods of forming the securities portfolio in the conditions of instability of the Ukrainian stock market are considered. It describes the process of forming a securities portfolio, which is divided into five stages: determining investment objectives and priorities, conducting an analysis of securities, creating a portfolio and choosing management tactics, revising a portfolio and evaluating portfolio performance. On the basis of Markowitz’s model and Tobin’s model are developed algorithmic, informational and software. The applied capabilities of portfolio investment models are explored, which realize the main idea of Markowitz to form an optimal securities portfolio, while at the same time having fundamental differences. And the main difference Tobin’s model, which includes a certain risk-free asset, along with risky securities. An optimal securities portfolio is being built using ten risky stocks of various sectoral activities of Ukrainian enterprises using the Markowitz model and using risk-free assets (government corporate bonds) for the Tobin model. Also the composition, profitability and risk of the optimal portfolio in the Ukrainian stock market are determined. In addition, a graph of profitability and risk dependencies is constructed, where each point of the chart is a certain portfolio with a certain number of investments in the stocks of listed companies. The conclusion is made on the results obtained, focusing on their difference depending on the choice of the model of portfolio formation.
Assessment of probability of lightning direct strike into elements of stationary ground launch complex (англійською мовою)
(НТУ "ХПИ", 2018) Kniaziev, Volodymyr Volodymyrovych; Melnik, Sergiy Ivanovych
Materials presented in the paper are the first stage of realization of methodology of ensuring the required level of protection of rocket space complexes from destabilizing action of lightning. The methodology is an obligatory element of ensuring a life cycle of the complexes and is logically integrated into the system of standards of IEC 61508 series. The presented first stage includes a calculated estimation of probability of lightning direct strike into elements of the complex. The estimation was carried out with using a method based on calculation of distribution of intensity of stationary electric field over the surface of objects of the complex. It is shown that it is sufficient to use only a variant of vertical, in relation to the ground surface, vector of intensity of electric field created by a thundercloud.
Cadmium sulfide thin films for flexible solar cell received by magnetron dispersion method
(Національний технічний університет "Харківський політехнічний інститут", 2018) Zaitsev, Roman Valentinovich; Kirichenko, Michailo Valerievich; Khrypunov, Gennadiy Semenovich
For the purpose of creation of the economic, suitable for large-scale application technology of formation of a layer of wide-scale "window", for thin-film photo-electric converters on the basis of sulfide and telluride of cadmium the pilot studies of temperature effect of a deposition of the films of sulfide of cadmium received by method of magnetron dispersion on a direct current on their optical properties and crystalline structure were conducted. By method of a two-channel optical spectroscopy it is established that a deposition of films of sulfide of cadmium at a temperature of 160 °C allows to form layers with a width of forbidden region of 1,41 eV that approaches value, characteristic of monocrystals, a nd the density of the photon flux passing through a cadmium sulfide layer in a spectral interval of a photosensitivity of telluride of cadmium at the level of 37,0 W·nm·cm2. Body height of precipitation temperature to 160 °C leads to decrease in optical losses in cadmium sulfide films, as a result of increase in the sizes of areas of a coherent scattering and decrease of level of macrodeformations. At further increase of precipitation temperature up to 230 °C the defining factor leading to growth of optical losses in cadmium sulfide films becomes their imp overishment by an easily volatile component – sulfur.
Case Study: Розробка концепції корпоративного web-порталу банку "Credit Agricole"
(НТУ "ХПІ", 2018) Золотарьова, Ірина Олександрівна; Плеханова, Ганна Олегівна; Плоха, Олена Борисівна
Розглядаються підходи до розробки концепції корпоративного веб порталу міжнародного банку. Будь-якій компанії (підприємству) необхідний інформаційний супровід своїх бізнес-процесів, а також інформаційна взаємодія у режимі online як усередині підприємства, так і із зовнішнім середовищем. Зі зростанням кількості співробітників і джерел корпоративної інформації стає усе складніше реалізувати внутрішні комунікації. Виникає потреба в єдиному інформаційному середовищі та оптимізації спільної роботи з інформацією й документами. Із цього погляду, портал – це один з потужних інструментів управління бізнесом компанії. Подані характеристики корпоративного інформаційного порталу в різних аспектах його функціонування як системи. Виділено три основні функціональні шари у складі типового корпоративного порталу, такі як шар базової інфраструктури, відповідальний за базові сервіси, шар інтеграції додатків, відповідальний за взаємодію порталу з усіма існуючими в компанії додатками (СКБД, CRM, ERP та ін.), шар інтерфейсів, що включає в себе засоби управління інформаційним наповненням, інтерфейси для обміну даними з інформаційними системами бізнес-партнерів, засоби для роботи з мобільним й бездротовим обладнанням та ін. Розглянуто концептуальні вимоги до корпоративного інформаційного порталу. Проведений аналіз характеристик корпоративного інформаційного порталу. Проаналізовано призначення порталу. Розроблені вимоги, діаграма варіантів використання, макети порталу. Виділені основні групи користувачів корпоративного інформаційного портала. Застосовані UML діаграми варіантів використання для опису користувачів та зв’язків між ними. Для кожного варіанта використання описаний сценарій його виконання, короткий опис, передумови, основний потік подій, альтернативний потік подій, постумови. Розглянуто крос-платформний сервіс Figma для дизайнерів, який дозволяє декільком людям в режимі реального часу працювати над одним і тим же проектом.
CFD-моделювання теплоаеродинамічних характеристик поверхні з гвинтоподібних труб
(НТУ "ХПІ", 2018) Рогачов, Валерій Андрійович; Терех, Олександр Михайлович; Баранюк, Олександр Володимирович
Засобами CFD-моделювання досліджений конвективний теплообмін та аеродинамічний опір шахових пучків гвинтоподібних труб з рівнорозвиненою поверхнею в діапазоні зміни чисел Рейнольдса від 9,5∙103 до 45∙103. Вивчені моделі пучків з відношеннями кроків між трубами s1/s2 = 0,46, 0,92 і 1,83. Пучки формувались з трьох досліджених типів однозахідних гвинтоподібних труб, які відрізнялися кроком гвинтової лінії – t = 8, 12 i 20 мм. Зовнішній діаметр D = 16 мм, глибина виступів-впадин h = 2,5 мм і загальна довжина l = 428 мм досліджених труб не змінювались. Запропоновані залежності для розрахунку конвективних коефіцієнтів тепловіддачі і аеродинамічного опору шахових пучків гвинтоподібних труб. Приведений теплоаеродинамічний розрахунок повітронагрівача-регенератора.
Cognitive tensor model of a system based on Von Neumann classes
(НТУ "ХПІ", 2018) Tikhonov, V. I.; Tikhonova, O. V.
The paper focuses issues of tensor calculus study in technical universities. To promote a holistic insight on tensors by undergraduates, there proposed a cognitive tensor model of a physical system on the base of hierarchical John Von Neumann classes.
Comparative study interleaved inverter with boost stage and active decoupling circuit
(НТУ "ХПІ", 2018) Fesenko, A. P.; Matushkin, O. O.; Husev, O. O.
Google little box challenge competition attracted high interest to problem of size and cost reducing of the converter as a part of photovoltaic power supply system. One of the ways is find a proper topology of the inverter. Selected for analyze solution is interleaved inverter. The assumption is made that the energy in passive component is in proportion through the inductor current. The reducing of the energy in passive component is expected for the selected solution. Selected schema consists of three main functional blocks. The first one is parallel boost converter with interleaving of switch control signal. The second part is an active decoupling circuit. Its main role is reducing of power pulsation on input of the inverter. And the third part is single phase interleaved inverter with output LCL filter. For estimation of energy reducing conventional solution also was considered. As conventional solution boost full bridge inverter with active decoupling circuit was selected. It consists of the same functional parts without interleaving switch control signals. The main goal of this paper was the definition and presentation the efficiency of boost interleaved inverter with active decoupling circuit in field of size and value optimization for inductors. Two models are made for simulation of both schemas. As simulation environment PSCAD version 4.5 is used. Both schemas have the same parameters: input voltage 150 V, output power 1 kW, switching frequency 50 kHz.
Cost and complexity research of software development to solve the problem of inventory management
(НТУ "ХПИ", 2018) Zarudniev, Maksym Andriiovych; Huzhva, Viktor Oleksiiovych
The article describes the process of estimating the cost and complexity of software development for the task of inventory management of a commercial enterprise to improve the decision-making process at the stage of formation of requirements for similar software products. There are different approaches to inventory management of a commercial enterprise. The algorithms implemented in the system are based on the constraint theory tool –dynamic inventory buffer management. Inventory management according to the theory of restrictions allows to provide a high level of availability of goods with minimal inventory in the system. After analyzing the subject area of inventory management and the methodology of dynamic inventory buffer management, a list of functional and non-functional software requirements was formed, and a data model was designed. The information obtained was used to compile a list of logical files and transactions specific to a particular requirement. From the resulting list of files and transactions, it is determined which elementary data, elementary records and links to files they consist of. The information obtained was used to estimate the size of the software at non-aligned functional points. To take into account the impact of non-functional requirements on the complexity of software development, the VAF alignment factor was calculated, for which it is necessary to give a qualitative assessment of the impact of system-wide requirements on the complexity of the software. The estimation of the complexity of the development was obtained using the COCOMO II methodology, namely, using seven multipliers of the complexity for the case of the initial assessment at the stage of approval of requirements. The calculations were obtained for teams with different professional level and equipment, in the conditions of a significant tightening of the development process, a high level of certainty of risks, without a rigid schedule of work. The cost of development was calculated for several common programming languages: J2EE, C#, C++.
Developing algorithms of optimal forecasting and filtering for some classes of nonstationary random sequences
(НТУ "ХПІ", 2018) Cheremskaya, Nadezhda Valentinovna
The problem of forecasting and filtering non-stationary random sequences is solved in the article. Optimal forecasting and filtering are performed using linear estimates and minimizing the mean squared error. For non-stationary random sequences, even with the correlation functions of the simplest form, such studies were not conducted. In this work, on the examples of non-stationary sequences, the problem of forecasting and filtering is solved explicitly. The correlation function image is obtained using the Hilbert approach, which allows one to calculate correlation functions as scalar products in a corresponding Hilbert space. The solution of the extrapolation problem with particular correlation function considered in the article can be used to simulate filtration and forecasting processes in real systems in the case of non-stationary random signals.
Development an antivirus scanner based on the neural network ART-1
(НТУ "ХПІ", 2018) Gavrylenko, Svitlana; Babenko, O. S.
In this article, the methods for constructing antivirus programs, their advantages and disadvantages are considered. The PE-structure of malicious and safe software was analyzed. The signs that are typical for classes of malware such as Worm, Backdoor, Trojan and for the safe software were identified. A software model of the device for detecting malicious software based on the neural network ART-1 was developed. This system was trained on the example of the obtained binary vectors. Optimal similarity coefficients were found, and the testing was performed. The test results showed the possibility of using the developed system to detect modified malicious software.
Development and research of models and software for the recommender system of consumer goods
(НТУ "ХПІ", 2018) Turetskyi, Andrii Olehovych; Vorona, Borys Mykhailovych; Vovk, Maryna Anatoliivna; Yershova, Svitlana Ivanivna
There have been proposed investigation of the problem of creating recommendations with technical description for building the Recommender System of consumer goods with help of modern algorithms, approaches, principles and contains the investigation of the most popular methods. It was defined, that the deployment of Recommender Systems is one of the rapidly developing areas for improving applied information technolog ies, tools for automatic generating offers service based on the investigation of the personal needs and profile of customers. It was investigated, that such systems have started to play a very important role in the fast growing Internet, as they help users to navigate in a large amount of information, because users are not able to analyze a large amount of information, because it is very difficult and takes a lot of time and effort, but due to such systems, namely Recommender Systems that are able to filter a large amount of information, and provide for users the information and recommendations their likes the problem can be solved and instead of providing the static information, when users search and, perhaps, buy products, Recommender Systems increase the degree of interactivity to expand the opportunities provided to the user. It was defined, that Recommendation systems form recommendations independently for each specific user based on past purchases and searches, and also on the basis of the behavior of other users with help of recommendation services, which collect different information about a person using several methods and at the same time all systems are shared. An overview of content-based, collaborative filtering and hybrid methods was performed. An overview of Alternating Least Squares and Singular Value Decomposition recommendation algorithms was performed. The design of the Recommender System of consumer goods software component was described. The main features of software implementation and programming tools for the system which is being developed were explained. The conclusions about the problems of Recommender Systems and the review of existing algorithms were made.
Development of agent-oriented software components to retrieve the marketing information from the web
(НТУ "ХПІ", 2018) Cherednichenko, Olga Yurevna; Melnyk, K. V.; Kirkin, Stanislav Vasylevich; Sokolov, Dmitry Vitalevich; Matveev, Alexander Nikolaevich
The article is devoted to researching the processes of extracting marketing information from the Web space. Conclusions are drawn on the need to introduce an information marketing system into modern business activities. A decision has been taken to develop software for the collection and analysis of marketing information. Identified and analyzed the main problems of collecting marketing information in the Web space. External systems for extracting and processing marketing information from the Web space were considered. During the analysis of the subject area, functional and non-functional requirements for the software being developed were formulated. Requirements for the selection of technologies for the development of an information system were defined. The analysis of software development technologies is carried out and the approach to the development of a software component is chosen. Such approaches to software development as: object-oriented programming, service-oriented architecture, component-oriented programming, agent-oriented programming were analyzed. A decision has been made to use the agent three-tier architecture in software development. The most commonly used programming languages in programming systems were: Java, KIF, KQML, AgentSpeak, April, TeleScript, Tcl / Tk, Oz. Analyzed such popular agent platforms and their functions as: JADE, Cougaar, ZEUS, Jason. For the development of software, the JADE platform was chosen, its classes, methods and interfaces were examined. The advantages and peculiarities of the SOLID principle are analyzed. In detail, the levels of the CLEAN architecture are examined. And also explained the possibilities of software implementation of this architecture. A software architecture was developed for the data collection system. In accordance with the requirements, a selection of software development tools has been made. It was decided to use the programming language Java, Spring Framework, GoF design pattern, the template Dependency Injection, SOLID and CLEAN architectural principles. A software component was developed for marketing information gathering systems, which allows to optimize this process. The limitations and ways to improve the software system are analyzed.
Development of software for effective enterprice product policy creation
(НТУ "ХПІ", 2018) Lysytskyi, V. L.; Morhun, Ya. Yu.
The problem of developing a software tool for an effective enterprise product policy creation is considered. Existing methods for an enterprise product policy creation require the execution of a large number of computational operations, and those operations can be processed faster and more accurate by using of personal computers. The object of this research is IT-enterprise which is developing web-applications for automatization of relationships between enterprises and clients. The main point of the work is developing of program tool that uses algorithmic model of information technology for enterprise product policy creation to increase enterprise profitability. During the work, the current state of the problem of enterprise product policy creation, as well as existing software tools that could be used to create the enterprise product policy, were considered. A review of existing software development methodologies was performed. The task about developing of algorithmic model, software tool architecture and program system for enterprise product policy creation was set. The software tool that is developed contains of several functional modules. There are listed algorithms that describe how those modules work. The algorithmic model uses hierarchy analysis method for creation of assortment of product policy and simplex method for solving task of linear programming for calculation of production volumes for chosen products. The functional and non-functional requirements were developed for program, the three-layer software architecture of the web-application was chosen, program code was written, and program system was tested. The graphical user interface was developed and described. The graphical user interface provides users with ability to enter information, which is required for enterprise product policy creation, and retrieve results which are set of products, that enterprise should produce, and volumes of production of those products. The conclusion about results of developing program system and the possibility to use the algorithmic model in future researches were made. The results of the work can be used for development of information technology of enterprise product policy creation.
Development of the model of a domain representation in the decision support systems
(НТУ "ХПИ", 2018) Dvukhglavov, Dmytro Eduardovych; Dolgorukov, Alexey Veniaminovich; Shovkoplias, Serhii Rostislavovich
The amount of information to be processed to make effective and informed decisions in the enterprises management in modern conditions of social development necessitates the use of decision support systems (DSS). Systems of this class provide storage and processing of large volumes of necessary information in a certain domain. At the same time, the high dynamism of the modern world leads to the fact that the domain represented in the system may change. This feature of modern conditions of DSS use determines the relevance of ensuring the adaptability of this systems class. This article presents the results of research on improving considered systems adaptability by providing the possibility of the modifying domain model represented in system being without making changes to the software architecture. The studies were aimed at resolving the discrepancy between the requirements of the systems adaptation efficiency to new functioning conditions and the actual duration of the existing adaptation procedures. It is shown that the traditional approach to the model representation, based on the mapping of the domain model in the relational database structure requires the involvement of specialists in the databases development and data access software. Standard procedures for the execution of such applications can take a long time. The approach which assumes that the domain model is stored in a special type of database in which the description of real objects, their attributes, attribute values and relations between them become records in the tables of such a database has been proposed as a solution for the discrepancy. This determines the possibility of the domain model modifying by changing of the tables contents without modifying structure of such database. To determine the such database structure, the domain representation model formalized description based on set theory has been made. The proposed approach is the basis for a software system design, using which will allow to modify the specific domain model directly by decision makers without involving correspond software developers. The primarily implementation area of the proposed solution is data-oriented DSS.
The device for measuring colour
(НТУ "ХПІ", 2018) Horoshaylo, Yuriy Evgeniyovych; Yarmak, Ivan Mykolayovych; Efimenko, Sergіy Andrіyovich
In this paper, the authors propose a device for measuring the color characteristics of light reflected or transmitted through an optical medium. The main element of this device is the measuring transducer, which assigns to each radiation three signals proportional to the color coordinates. Existing devices have many drawbacks, among which low speed, due to the use of inert elements, which makes it impossible to measure rapidly changing light fluxes. In this device, the authors tried to minimize these limitations by using photodiodes and a microcontroller with a built-in ADC and other devices. Also in this article, a mathematical model of the device is proposed. Attention is paid to psychophysiological perception of color. As a result, we found a device that has a number of advantages over its counterparts, which makes it possible to perform color measurement with higher accuracy.
Discrete mathematical model of hypersingular integral equation on a system of intervals
(НТУ "ХПІ", 2018) Polyanskaya, Tatyana Semenovna; Naboka, Olena Oleksiyivna
We consider a hypersingular integral equation on a system of intervals, which is reduced to a system of hypersingular integral equations on the standard interval (−1,1). The discretization of this system is carried out on the basis of the method of discrete singularities. The unique solvability of the discrete problem is proved and an estimate of the rate of convergence of the solution of this problem to the exact solution of the system of hypersingular integral equations is given.
Distance learning reforming swedish experience implementation into ukrainian higher education system
(НТУ "ХПИ", 2018) Ageicheva, Anna; Komarova, Oleksandra; Babash, Larysa
The article deals with the conceptual ideas of distance education in the European Higher Education Area and future prospects definition in distance learning implementation into higher education system of Ukraine. Development system of higher education and distance learning development stages are analyzed. The main goal of creating distance education in Ukraine is to increase the level of education of the society and the quality of education, as well as the formation of a single educational space. It is necessary to address such major challenges as the formation of legal, organizational, teaching, information and telecommunications, logistics, personnel, economic and financial support. The development of distance education will not only provide our population access to quality education, but also provide an opportunity to take a place on the global education market.