2016

Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/21405

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Зараз показуємо 1 - 20 з 1050

Calculating three-dimensional fluid flow in the spiral casing of the reversible hydraulic machine in turbine mode
(НТУ "ХПИ", 2016) Drankovskiy, Viktor Eduardovich; Rezvaya, Kseniya Sergeevna; Krupa, Evgeniy Sergeevich
One of the stages of a numerical research of water passage of the reversible hydraulic machine in turbine mode was described with program packages. Graphical results in the form of the velocity and pressure distributions in the predetermined modes of operation of reversible hydraulic machine were obtained. On the basis of these data can beobtained average kinematic parameters of the flow, which are determined in the inlet of calculation domain. Analysis of this numerical research was performed.
Comparison HRC and C-C gearing for damage to pitting
(НТУ "ХПИ", 2016) Kopilakova, Beata; Bošanský, Miroslav; Petrak, Lubomir
In this article are comparison HCR and Convex-Concave (C-C) gearing from the point of view to pitting. The introduction of the article describes a fundamental difference between the involute HCR and noninvolute (C-C) gearing and the influence of some parameters, especially of the slip ratio to damage of gearing. The paper also shows the basic results of the experiment, which was executed on two types of gearing (involute HCR gearing and noninvolute C-C gearing) on the Niemann's stand from the point of view damage flank of tooth to pitting.
Consideration the influence of residual stresses and creep strains on rolling the steel sheets
(NTU "KhPI", 2016) Breslavsky, D. V.; Mietielov, V. O.
The method for considering the residual stresses which occur by plastic deformation during the rolling process in creep stress-strain state of steel plates in tension is discussed. The problem’s solution is divided on two stages. First one presents the modeling of the problem of plasticity with consideration of finite strains. The rolling process of steel sheets with two rolling mills is regarded. The scheme of technological process and its numerical simulation are described. Obtained stress-strain field in a plate after rolling was considered as a residual for creep initial-boundary value problem, which presents the second stage of analysis. The mathematical problem statement including state equations are built by use of the determined anisotropic creep properties of considering steel 3 at room temperature is presented. The transition procedure from three dimensional to two dimensional stress strain state in considered plate is discussed. Creep problem solution was done by use of developed two-dimensional Finite Element Method codes which include time step integration schemes. The numerical results like stress and strain fields, dependencies between the traction values and maximum plate’s displacements, deformed shape of the plate edge as well as the recommendations for safety conditions of technological process are presented.
Context approach for electric grid control
(НТУ "ХПИ", 2016) Verbitskyi, I. V.; Kyselova, A. G.
The necessity of using the parallel connection of renewable energy sources (RES) at an electric grid which leads to a complicated control is shown. The control improvement on basis additional data about the environment and the grid infrastructure is described. The data formalizing to a context for decreasing calculation complexity and using expert knowledge is proposed. The example of context using is shown. A hierarchical control system on basis variety of data representation is shown. A flexible structure of control unit is proposed.
Conveyor module resource scheduling in packet based communication channel
(NTU "KhPI", 2016) Tikhonov, V. I.; Taher, A.; Tykhonova, O. V.
The paper focuses researches on channel resource reservation and scheduling in packet based networks. An axiomatic basis for enhanced packet based internetworking design formulated. A cross-layer method originated to leverage integrated heterogeneous data flow in converged digital channel based on cyclic conveyor module resource scheduling.
Dangerous Bifurcations in 2-DOF Vibroimpact System
(NTU "KhPI", 2016) Bazhenov, V. A.; Pogorelova, O. S.; Postnikova, T. G.
Dynamic behaviour of strongly nonlinear non-smooth discontinuous vibroimpact system isstudied. Under variation of system parameters we find the discontinuous bifurcations that are the dangerous ones. It is phenomenon unique to non-smooth systems with discontinuous right-hand side. We investigate the 2-DOF vibroimpact system by numerical parameter continuation method in conjunction with shooting and Newton-Raphson methods. We simulate the impact by nonlinear contact interactive force according to Hertz’s contact law. We find the discontinuous bifurcations by Floquet multipliers values. At such points set-valued Floquet multipliers cross the unit circle by jump that is their moduli becoming more than unit by jump. We also learn the bifurcation picture change when the impact between system bodies became the soft one due the change of system parameters. This paper is the continuation of the previous works.
Development of the controller for the quadcopter Finken in simulation enviroment VRep
(NTU "KhPI", 2016) Severin, Valeriy Petrovich; Nikulina, Elena Nikolaevna; Buriakovskyi, Vladyslav Serhiiovych
The problem of control of quadcopter Finken, that was created at department of Intellectual systems at Otto von Guericke University Magdeburg, was presented. The simulation environment VRep as 3D robot simulator was reviewed. The general mathematical model of copter was presented and the model of quadcopter Finken was created in VRep simulation environment. The principles of working continue and discrete PID controllers were described and analyzed. The models of motion of quadcopter Finken were reviewed and implemented in simulation environment VRep. The model of recommended PD controller for quadcopter Finken was described and implemented. The test flights were done and the stable flying motion of quadcopter was received. The conclusions about possible use such a model was made.
Energy project management system: benefits, principles and risks
(НТУ "ХПІ", 2016) Dedelyuk, Kateryna Yurivna
The essence of an effective energy project management system was described, as well as the main benefits of its implementation at the company level were characterized. Such outcomes as possible savings unlocking, improving risk management, reliability and productivity, reputational issues where described as key results from realization of an energy project management system. Among the main principles according to which an effective energy project management should be implemented the fallowing aspects were discussed: leadership and responsibility, energy policy and energy performance, communication and continuity of energy policy. The conclusions about the main risks that may occur during implementation of an effective energy project management system were also systematized in this article.
The formation of anti-crisis program of the industrial enterprise based on innovative monitoring
(NTU"KhPI", 2016) Pererva, P. G.; Kobielieva, Tetiana
The mechanism antisavage management and sustainable development engineering pidpriemstva. Conducted analytical research of existing methods of restructuring and reorganizing industrial enterprises. The original classification of methodological approaches to the sustainable development of industrial enterprises the recommendations for justification of the most significant indicators of diagnostics of the crisis state machine-building enterprise with the use of correlation and regression analysis. Developed a comprehensive system of crisis monitoring through the use of trigonometric functions, which includes the most significant indicators and allows to mathematically reasonable intervals and in the anti-crisis terms to interpret the economic results of the company.
GERT–модель начальной генерации кода кибератаки несанкционированного доступа к ресурсам компьютерной системы одноранговой сети
(НТУ "ХПИ", 2016) Семенов, Сергей Геннадьевич; Лисица, Дмитрий Александрович; Мовчан, А. В.
Разработана математическая GERT-модель начальной генерации кода кибератаки несанкционированного доступа к ресурсам компьютерной системы одноранговой сети, отличающаяся от известных учетом основных этапов генерации в процессе математической формализации GERT-сети. В ходе моделирования получено аналитическое выражение для расчета времени генерации кода кибератаки несанкционированного доступа. Сделаны выводы о дальнейших практических разработках, связанных с полученными в статье результатами.
Identification of human eye-motor system base on Volterra model
(NTU "KhPI", 2016) Pavlenko, V. D.; Fomin, O. O.; Fedorova, A. N.; Dombrovskyi, M. M.
A new method of constructing nonparametric dynamic model of the human oculomotor system on the basis of experimental data "input-output". This takes into account nonlinear and inertial properties of the eye of the rectus muscles. A technology for tracking eye movement based on the videos. It is possible to determine the dynamic characteristics of the oculomotor system functions as a transition of the first and second order - integral transforms Volterra kernels.
Incipient regimes of drill bit whirlings on uneven bottoms of deep bore-holes
(NTU "KhPI", 2016) Gulyayev, Valery Ivanovych; Vashchilina, Olena Valeriyivna; Glazunov, Sergiy Mykolajovych
This paper studies the problem of whirl vibrations of rotating drill string bit under conditions of its contact interaction with the borehole bottom surface. The destructive effects of whirl vibrations of drill bits and drill strings have long been recognized. The backward whirling is believed to randomly happen to some degree in 40 % of all wells. It is shown that the situation is essentially associated with enlargement of the compressive thrust force and its approaching to the Eulerian critical value. Then, the bending stiffness of the drill string reduces, it hogs and the diamond impregnations existing in the bit surface penetrate into the rock medium. As this takes place, the bit axis tilts and nutates. It should be particularly emphasized that at this stage, the bit is under action of the vertical force (weight on bit) which essentially exceeds all other forces. It presses the bit to the hole bottom (not to the hole wall) and the bit loses its ability to slide on the bore-hole bottom and begins to roll on its surface, lagging behind or outstripping the drill string rotation. As a result, the point of the bit contact with the reference surface (the instantaneous centre of velocities) may describe extremely complicated trajectories with loops and cuspidal points and to change the motion directions. As examples, whirling of spherical bit is considered.
The integration models of procurement management of hybrid projects in development of project-oriented enterprises
(НТУ "ХПІ", 2016) Morozov, Victor V.; Liubyma, Iuliia O.
The aspects of resource provision of project implementation in development of project-oriented organizations and its positioning on domestic and international markets are studied in the article. It significantly affects not only the results of projects` research, but also the sustenance and development of such organizations. For realization of stated tasks, the authors proposed several conceptual models that allow to combine the processes of project management and operational processes of the company and on this basis to create hybrid projects for efficient procurement of product components and resources for project portfolio.
Marketing characteristics of the innovation and investment activity of the enterprise
(НТУ "ХПІ", 2016) Pererva, P. G.
Studied marketing characteristics of the innovation and investment activity of industrial enterprise. It is proved that wines characteristics of the demand for innovation is the speed at which innovation spreads among the companies. This parameter characterizes increase of the new product, increasing demand, winning it all new and new areas of consumption it is Proposed to divide innovations into two groups: with extensive and intensive nature of distribution in the market. The intensity and extensiveness of distribution are to avoid the most progressive scientific and technical ideas after its practical materialization in a specific product. In the initial stages of the innovation life cycle to a greater extent inherent in the intensive propagation and then to an increasingly greater extent manifested extensive that by the end of the life cycle of innovation already is usually determining. The main factors that determine the size of market demand for new products. Special attention is paid to the size of the firm, the payback period of innovation, the existence of the patent system, the characteristics of the market segment.
The mathematical model of heat transfer in Matlab for device of cardiopulmonary by pass in cardiology
(NTU "KhPI", 2016) Котовський, Віталій Йосипович; Шликов, Владислав Валентинович; Данілова, Валентина Анатоліївна
The heat transfer models for device of cardiopulmonary bypass in the form of a system of ordinary differential equations are presented. The numerical model allows us to estimate the temperature of the process parameters of hypothermia and hyperthermia heart and to investigate changes in the gradient of the temperature on the surface of the myocardium at the time of registration of thermal images of the heart. The numerical model of heat transfer during extracorporeal circulation in the form of a system of ordinary differential equations was created. It allows to estimate the parameters of temperature propagation and temperature gradients at the surface of the myocardium at the time of registration of thermal images of the heart. Comparison of the model with real patients intraoperative infra-red thermography shows that this method can provide additional important information regarding temperature and vascularuniformity in time of myocardial cooling and heating. This method increasing safety of myocardium protection and assistive in solutions ofweaning from cardiopulmonary bypass.
Model and method for synthesis of project management methodology with fuzzy input data
(НТУ "ХПІ", 2016) Kononenko, Igor Vladimirovich; Aghaee, Ahmad
Literature analysis concerning the selection or creation a project management methodology is performed. Creating a "complete" methodology is proposed which can be applied for managing projects with any complexity, various degrees of responsibility for results and different predictability of the requirements. For the formation of a "complete" methodology, it is proposed to take the PMBOK standard as the basis, which would be supplemented by processes of the most demanding plan driven and flexible Agile Methodologies. For each knowledge area of the PMBOK standard, the following groups of processes should be provided: initiation, planning, execution, reporting and forecasting, controlling, analysis, decision making and closing. The method for generating a methodology for the specific project is presented. The multiple criteria mathematical model and method are developed for synthesis of methodology when initial data about the project and its environment are fuzzy.
Model of the situations recognition in conditions dissimilar and incomplete data
(NTU "KhPI", 2016) Dvukhglavov, Dmytro Eduardovych; Muzyka, Oleksandr Volodymyrovych; Hlazkov, Stanislav Oleksandrovych
There have been proposed model of situations recognition in determined alphabet, based on combination of quantitative and qualitative characteristics, considered the data dissimilar, coming from information sources. In the model improved the quality of the formalized description of quantitative characteristics using histograms instead of fuzzy L-R intervals, which gives the possibility of organizing a self-learning recognition system situations based on the processing statistics of recognition. Recommendations for formation of characteristics sets to overcome the data incompleteness have been present. Proposed model may be use for formalization knowledge about situation recognition process. Subject areas for implementation taken results are diagnostic in medicine and energetic, situation assessment at the military control points, making prognosis in ec onomic.
Modern information technologies of creating documents according to quality management standards based on ISO 9000
(НТУ "ХПІ", 2016) Yarka, Ulyana; Myna, Zhanna; Peleschyshyn, Oksana; Bilushchak, Тetiana
Introduction of quality management system (QMS) according to the international standard ISO 9001-2008 enhances the providing of European quality service, which is issue number one for Ukraine. The process of standardization involves huge amount of paperwork and thus arises the question of rational approach to creation methods of such documentation in view of its peculiarities. The software and various methodologies for the creation of such documents have been considered. The main focus has been on the free software, to which there is unlimited access in the Internet. One of the universal methods of work automation is creating document templates. The information technologies of creating such templates based documents with the help of OpenOffice.org and with additional use of built in programming language of OpenOffice.org. Basic are presented. The introduction of such templates will enable complying with the requirements of standardization, avoiding mistakes, ensuring the minimum time of QMS processing of documents, and thus improving the quality of work and introduc ing the given standards.
Modified moving-average method in problems of short-term forecasting of technical and economic indicators in high-technology enterprises
(НТУ "ХПІ", 2016) Kovalenko, I. I.; Chernova, L. S.
This paper proposes a modified moving average method. The basis of the method is to find an effective average estimator on the basis of moving that consists of some subset of the elements of the average series. To improve accuracy of the obtained forecast values the averages test for efficiency at each step of moving is done by the resampling method. This method is actively used in technical and economic analysis, as it has a profound statistical justification. The obtained forecast error values are acknowledged as possessing "satisfactory accuracy" and "good accuracy". Accordingly, the modified method has advantages over other modifications of the moving average method. In future studies of the proposed method in different time series, for example, with so-called "suspicious", "outlier" values the new results can be obtained.
Olfactometry diagnostic at the modern stage
(НТУ "ХПИ", 2016) Avrunin, О.; Shushlyapina, N.; Nosova, Y.; Bogdan, О.
In this article we consider the most popular methods for evaluating the degree of olfactory disorders. The purpose of our paper is an analytical review of olfactometry of methods and tools to determine their potential and the diagnostic value of the detection of respiratory-olfactory disorders (blocking of odorants getting into areas of the nasal mucosa, containing olfactory receptors). Purpusful study of olfactory function allows to determine the criteria for the diagnosis of local destruction of various parts of the analyze. Various methods and devices (olfactometers) are used to diagnose olfactory analyzer, but they all have a number of drawbacks: the long duration of the study, the use of objective evidence of the subjects, the use of olfactory substances that affect the end of the threefold nerve, determination of olfactory dysfunction or only quantitatively or only qualitatively. Most of the methods for evaluating of olfactory disorders have a wide range of uses for the diagnosis of various diseases as well, including mental disorders, brain damage, and nervous system. However, within our problem, olfactory dysfunction is necessary to consider in connection with the problem of the air passage in the human olfactory system. Therefore, it is necessary to develop a highly specialized method of assessing olfactory – respiratory disorders, which would have a high degree of objectivity for use in clinical practice of otolaryngologists. Thus, in the perspective of further research it seems necessary to develop a method of assessment of olfactory function on the basis of respiratory parameters derived from rinomanometry research that will improve the objectivity of conducted researches.