Статьи журнала - Журнал Сибирского федерального университета. Серия: Техника и технологии
Все статьи: 1404
Regularities of formation of the ordered structures in refractory metals at ion implantation
Статья научная
Is shown, that the character of structural - phase transformations in tungsten and tantalum at ion implantation by the elements of the interstitial phase is defined, in the main, by the size factor, i.e. by the ratio of the atomic sizes of implanted elements and atoms of metal. The researches are carried out on tungsten and tantalum monocrystals at implantation by ions of, N, O, P.
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Статья научная
The purpose of this study was a comparative study of seasonal dynamics of chlorophyll potential, leaf area index and fresh biomass of different varieties of wheat based on refl ectance spectra obtained by ground-based remote measurements. The study reports data on seasonal dynamics of refl ectance of wheat canopies composed of various wheat cultivars in the Krasnoyarskii Krai. The study presents an optical remote method for determining chlorophyll potential, S(t), of wheat plants, which is calculated based on reflectance spectra of the crops during the growing season. Chlorophyll potential of wheat plants, S(t), may serve as an indicator of their physiological state and potential biological productivity; also, it can be used to predict grain yield of wheat fields. Different wheat cultivars have different chlorophyll potentials, S(t), during the growing season. There is high positive correlation between dry and fresh wheat biomass, and chlorophyll potential, S(t), of wheat plants. A digital database has been compiled, which contains spectral data of the wheat canopies studied.
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Reliability evaluation method of the wind-diesel installation with application of dynamic fault tree
Статья научная
Renewable energy sources becoming more widespread in decentralized power supply systems. However their functioning depends on the natural resources potential having variable character. This dependence influences reliable work of autonomous power supply system. Reliability analysis of a renewable energy based autonomous generating system is the actual practical task requiring the solution. For the reliability assessment of autonomous wind-diesel installation it is offered to use the method of dynamic fault tree with Markov models for representation of dynamic operators. The offered method is applied for reliability calculation of the wind-diesel installation functioning in the autonomous power supply system in the north of Krasnoyarsk region.
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Статья научная
This article represent the results of research of mechanical and electrical properties of deformed semi-fifnished products from alloys system Al-Zr, obtained with using methods of combined casting-rolling, combined casting and rolling-extruding and drawing.
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Статья научная
This article examines the issues of hydraulic resistance of solar air heaters with concave tubes and reduction of pressure losses, as well as the determination of the air flow in concave tubes installed in the working chamber of the solar air heater and discusses the reduction of the number of common tubes to reduce pressure losses in the solar air heater and the installation of concave pipes to give air a swirling motion to eliminate a sharp decrease in the heat transfer process.
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Статья научная
Satellite-to-ground optical communication link bit error rate (BER) depending on atmospheric propagation, pointing errors is considered. The theoretical and numerical estimations of BER for GEO to Earth link under various conditions are proposed.
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Satellite monitoring of grain crops in the south part of Western Siberia
Статья научная
In agriculture an important issue is to obtain reliable information on the status of agricultural land. The article presents the most recent results of grain crops’ status monitoring based on remote sensing data on the example of the south part of Western Siberia.
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Satellite monitoring system for the Krasnoyarsk territory area based on small satellites use
Статья научная
The satellite monitoring system for the Krasnoyarsk Territory area is proposed. The main feature of proposed system is its implementation at three levels: space, low altitude and ground levels. Each level assumes the use of data compatible spectrophotometric equipment for subsequent integrated interpretation. The development of ground system for control, data acquisition, processing and distribution is assumed.
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Search for the new form of raw material for the alyumineevoy industry of siberiaode
Статья научная
This article presents the results of research into rational schemes ore enrichment Bazybajsk deposit (Krasnoyarsk region). Optimal conditions for sillimanit and quartz concentrates.
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Статья научная
The actual problem of duly revealing of mechanical stressed sections of fiber optical communication lines, in particular, optical fibers which are under influence of the raised mechanical pressure (strain) in optical cables is considered in this paper. Results of modeling of Brillouin backscattering spectrum changes depending on change of optical fiber strain are presented. Results of experimental examinations of strain characteristics of various types optical fibers, which are under longitudinal and transverse mechanical influences, based on Brillouin backscattering spectrum analysis are given in this paper. Also are discussed temperature dependences of Brillouin backscattering spectrum changes of the optical fibers. The received results confirmed a possibility to detect problem (mechanical stressed) sections and estimations of the optical fiber strain degree on basis of Brillouin refl ectometry method at different mechanical infl uences.
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Shok-free dismounting of cathode assembly lining of aluminum cells
Статья научная
The technology of dismantle of the cathodic device of electrolytic furnaces is considered. Lining destruction in the cathodic device of an electrolytic furnace is made by a special hydraulic press. In a lining material locally non-uniform loadings causing occurrence of cracks are created. The technology allows to exclude with great dispatch-vibrating influence on near electrolytic furnaces and to increase term of their operation.
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Short distance data transmission method by using QR code
Статья научная
QR code (quick response code) has become a widely common technology along with the increase in the usage of smartphone. In many areas, QR codes have over taken the place of linear barcodes due to the obvious advantages of large data capacity and ease of data retrieval. In this paper, we propose a novel data transfer scheme that employs the camera in smartphone devices as an alternative data channel. The sender device encodes data as a series of QR code images like the video data type. The video will be exhibited on the screen of smartphones, tablets, or PCs. The receiver device records the video by camera, splits video into frames, and decodes the data from images. This method is implemented by using multiple versions of QR code started from 1 to 40. By conducting several experiments, the version 19 is the best choice for transferring data between smartphone devices because of it’s the ability to transfer 135 Kbit/s without error. To transmit data from tablets and PCs to smartphone devices, the best version of QR code is 29, which allows 277 Kbit/s to be transferred without error. Further, the proposed method shows the advantages of permitting satellite TV channels to transfer files to viewers instead of giving file links. This results in solving the problem of transferring files from IOS and Mac devices to windows and android devices and vice versa.
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Siberian centre of Russian satellite designing
Статья научная
Space technologies are not luxury, but essential requirement for economic and social development of the country and guarantor of national security. In the Krasnoyarsk region, along with major extractive industries successfully operates a high-tech enterprise in space design Joint - Stock Company Academician M.F. Reshetnev developing space technologies and ensuring economic growth of Russia.
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Sigmaflow как инструмент исследования ветрового комфорта в условиях городской среды
Статья научная
Интенсивный рост современных городов приводит к строительству жилых микрорайонов с плотным расположением зданий различной высотности. Подобные архитектурные решения способствуют непредсказуемому изменению аэрационного режима территории, который может вызывать ухудшение экологической обстановки города, а также формирование дискомфортных условий в зоне пребывания человека. Для изучения механизмов формирования данных условий и прогнозирования ветрового режима используется микромасштабная модель атмосферы города, реализованная в программе «SigmaFlow». В работе представлены результаты верификации численной модели с экспериментальными данными на двух тестовых задачах обтекания модельных элементов городской застройки. Полученные результаты расчетов демонстрируют достаточно хорошее совпадение с экспериментальными данными. Кроме этого, был выполнен анализ формирования ветровых условий в реальном жилом микрорайоне. Получены характерные структуры течения при обтекании зданий, а также выявлены места формирования дискомфортных и опасных зон для пребывания человека.
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Simulation and calculation of heat transfer in multilayer wall structures based on iterative models
Статья научная
Through heat transfer is considered: heat carrier, liquid medium 1 - wall of arbitrary n layers - liquid external medium 2, cooler. For heat flows, a system of (n + 1) nonlinear equations is considered. The method of excluding unknowns sequentially calculates all values of tw, i. The design scheme allows iterative calculations of wall temperature from one to three layers and, accordingly, five heat flows. The novelty of the solution is that the temperature of the first wall tw,1 and the last wall tw, n+1 are not set, but are unknown. They are calculated using an iterative scheme.If you further increase the number of wall layers, the calculations become cumbersome. We are talking about the explicit expression of all tw, i through formulas based on the manual transformation of equations. Optimally bringing the problem to a closed and defined system (n + 1) of equations for (n + 1) unknown wall temperatures tw, i. This system of equations is easily calculated in mass accessible packets, to which Matlab belongs. The advantage is a matrix solution of the entire system at once. In the case of a system of cylindrical and spherical walls, the problem is also solvable. New coefficients have been established for these systems of equations. Which allows you to save balance equations for heat flows.
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Simulation modeling accounting for reservoir fluid properties heterogeneity
Статья научная
Current article deals with fluid properties heterogeneity. The reasons of this phenomenon are analyzed. 3D digital modeling of formation, saturated with oil having variable properties (density and viscosity) is performed. It is compared with model, built in the frameworks of classic approach, where oil has constant density and viscosity. It is shown, that accounting for oil properties heterogeneity allows making oil field design and planning of different activities more precisely.
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Simulation of a continuous ingots structure formation process
Статья научная
The presented results demonstrate the possibility of mathematical complex model in research of the temperature characteristics pattern changes in polymorphic transformations, isotherms of liquidus and solidus, and other parameters depending on the cooling conditions of the ingot. Shown the possibility of predicting parameters of a continuous ingot microstructure (distance between dendrites, size of the austenite and ferrite grains). Were made microstructure parameter calculations of the continuous steel ignot containing 0.17 % C, 0.62 % Si, 1.4 % Mn at various secondary cooling modes.
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Статья научная
Under study was the reaction of the basic operating performance of the cold low-shrinkage ramming paste (CRP) on the pre-heating conditions of the rammed joint. It was found out that the uncontrolled high-rate heat-up of the cold ramming paste (CRP) loosens the macrostructure and intensifies impregnation of the rammed layer. The controlled delayed rate in the temperature rise of the inter-block joint up to 400 °С enables to obtain a high-quality layer of paste with the improved barrier properties against its impregnation with electrolyte.
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Simulation of three phase induction machine
Статья научная
Three phase induction motor is the most popular type AC motor. it is very commonly used for industrial drives. It is cheap, robust, efficient and reliable. It has good speed regulation and high starting torque. It requires little maintenance. It has a reasonable over load capacity. This paper deals with the simulation of three phase induction machine using MATLAB Simulink. The results are obtained for generating mode and motoring mode.
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Simulation of wind speed in the problems of wind power
Статья научная
The article is devoted to research of mathematical models of wind speed and development a way to improve the efficiency of wind power plants based on fuzzy logic using fuzzy model of the wind speed. Simulation of the wind speed is a fairly difficult task, since this source of energy is constantly changing in time and space. Four basic models of wind speed were identified at the end of research work: determinate, probability, spectral and fuzzy. Every one finds their own field of application. Thus, from the energy point of view, the model probabilistic distribution of Weibull is most applicable at the level of technical and economic development. Deterministic model allows to determine the power generated by wind turbines at a given average wind speed. The spectral model should apply in those studies where necessary to account for gusts of wind and sudden changes. Fuzzy model of the wind is the most convenient and relevant for modeling of wind turbine control, it is allows to form a flexible control system.
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