Статьи журнала - Журнал Сибирского федерального университета. Серия: Техника и технологии
Все статьи: 1404
The conjugate equations in the heterogeneous systems heat and mass exchange tasks
Статья научная
Conjugate equations based on a conception of the uniform mathematic description of a naturally equal heating transfer process in all points of a heterogeneous system is proposed. The equations may be applied to describe the heat and mass exchange processes in the divided boundaries of the heterogeneous systems instead of conventional IV type boundaries conditions. The modeling results of the underground coal gasification heat and mass exchange is adduced in the new problem definition.
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The evolution of smart wrist band by using sensors
Статья научная
In recent years, the integration of various electronic components and sensors with textiles aimed at giving additional functions has become more common. In this respect the wrist band can be made functional while retaining the aesthetic appeal and style at lower cost which is in high demand. Smart textiles are fabrics that have been designed and manufactured to include technologies that provide the wearer with increased functionality. Smart textiles can be produced by knitting, weaving and embroidering with conductive threads, conductive metal coating and screen printing that can be used to develop wearable electronic textiles but amongst these, the use of conductive inks onto textiles has gained interest due to the ease of their use and manufacturing scalability. The emergence of wireless technologies and advancement in on-body sensor design can enable change in the conventional healthcare system, replacing it with wearable ones, centered on the individual. Wearable monitoring systems can provide continuous physiological data, as well as better information regarding the general health of individuals. Thus, such vital-sign monitoring systems will reduce healthcare costs by disease prevention and enhance the quality of life. This dissertation is aimed at developing smart band by incorporating vital-sign monitoring systems. Using this assembly, the recent progress in non-invasive monitoring technologies for chronic disease management is reviewed. Devices and techniques for monitoring pulse rate and body temperatures are discussed in particular. For our research conductive ink and conductive fabrics are presented additionally. The main aim of this project is to produce a wearable wrist band which detects vital body parameters like pulse rate and temperature using sensors, conductive ink and conductive fabric. Finally, the recorded temperature and pulse rate readings are sent to mobile app via Wi-Fi.
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Статья научная
In this article the problem of increase in operability of a hydraulic actuator by use of a multiple-pass heater as means of cooling of working liquid is considered. For studying of thermal processes, check of mathematical model and an assessment of efficiency of application of a multiple-pass heater the developed experimental stand is given.
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The formation of regional spatial data infrastructure
Статья научная
In this paper the major characteristics of spatial data, its infrastructure and main components are discussed. Herein, spatial metadata and software and technical support for geoportals, as well as their services are examined. In this work technologies of development of applied geoinformational web-systems (geoportals) are discussed. Within the paper the software architecture and web services of the geoportal of Institute of Computational Modeling of Siberian Branch of Russian Academy of Sciences is presented.
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Статья научная
The theoretical basics of copper-bearing sulphide concentrate one-stage recycling technology in oxygen fuel-fired furnaces for blister copper (white matte) melting are stated. The pre-design furnace heat transfer characteristics investigation based on polyzonal mathematical model has been led. It has been found that the designed scheme of the unit with vertical charge-oxygen fires provides adequate durability and efficiency.
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Статья научная
The article describes the process of induction heating and the advantages of an induction furnace. The models of heating of the graphite crucibles and metal at different frequencies are shown. The technology of chromium bronze smelting in order to obtain cast electrodes for resistance welding is introduced in the current paper.
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The impact of recycling on the mechanical properties of 6XXX series aluminum alloys
Статья научная
Increasing the recycle content of a production stream is one of the easiest methods to reduce the cost of wrought aluminum products. This has economic and environmental benefits, but closed loop recycling systems do not reflect the conservation of the original composition, due to so called “tramp elements”. To understand the influence of certain tramp elements, a campaign of 950 AA6008 ingots were cast reflecting the entire scope of the composition window for this alloy, and the mechanical properties subsequently analyzed.
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Статья научная
This article is about calculations of U-shaped regions of water heat network. The universal calculation algorithm is used for various geometric schemes and simple self-compensating pipeline sections. The influence of slenderness ratio and stress concentration factor in the smooth curved bends on voltages and maximum permissible flight compensated shoulders of U-shaped regions for different geometric confi gurations was taken into account in this work.
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The influence of thallium additives on the kinetics of oxidation of the Zn22Al alloy
Статья научная
The article presents the results of a thermogravimetrical study of the effect of thallium alloying additives on the oxidation kinetics of the Zn22Al alloy. Established in the temperature range of 473-623 K the kinetic and energy parameters of the oxidation of alloys. The oxidation of alloys proceeds according to the hyperbolic mechanism and has the order of 10-4 kg∙m-2∙sec-1. Higher activation energies indicate that the oxidation of these alloy samples results in the formation of oxide films with good protective properties. Additives of thallium in amounts of 0.01-1.0 wt.% contribute to a decrease in the oxidizability of the Zn22Al alloy. The resulting products during the oxidation of the studied alloys consist of a mixture of oxides ZnO, ZnAl2O4, Al2O3, Tl2O3.
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Статья научная
The automated laboratory equipment for efficient interrupting electrocontact materials testing with respect to their general functional properties during their development and/or improvement is presented. The equipment for estimating erosion resistance, transient resistance of loaded pair contacts and also welding resistance during on-off cycles by break force measurement (380/220 V, current is 15-30 А, power factor φ=0.8, frequency of on-off cycles is 0.01-10 Hz, controlled duty cycle). The equipment control, monitoring, recording and primary processing of parameters taken from the detecting device are performed using specialized software. The equipment was tested on two type contact materials, Ag and Ag/(15%CdO). The results and appropriate correlation are presented in this article.
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Статья научная
The polyzonal mathematical model of heat transfer in the furnace with a liquid bath of Vanyukov smelting energotechnological complex has been improved and its design-theoretical analysis has been made. The paper gives quantitative estimation of influence on thermal condition of furnaces design characteristics: shapes and size of over layer space, the situation of uptake and place of charge load.
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Статья научная
The task of developing a method and information presentation algorithm for the exchange of complex hierarchical management system in terms of information overload. The criteria of inclusion of information aggregation algorithm. Finding of fact overload the system asked to carry out by comparing the distances between aircraft objects with preset thresholds, the amount of air objects in the processing system of the automated control system components and for each region of space, covert interference - the operator of the complex automation.
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Статья научная
The paper proposed an effective model of management of fuel and energy enterprises, developed on the basis of fuzzy logic, allowing to minimize the risks associated with incorrect forecasting of energy consumption, allowing to consider not only quantitative but also qualitative indicators of the enterprise.
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The numerical probabilistic approach to the processing and presentation of remote monitoring data
Статья научная
The paper deals with a numerical probabilistic analysis as a method of processing and presentation of remote monitoring for the aggregation large amounts of data. For the aggregation we used histograms, polygons and splines. On the basis of aggregated data to identify relationships between the input and output characteristics are studied the theoretical and the practical aspects of regression modeling. On the basis of numerical examples we demonstrated the effi ciency and reliability of the proposed methods.
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The performance of classifiers in the task of thematic processing of hyperspectral images
Статья научная
The performance of the spectral classification methods is analyzed for the problem of hyperspectral remote sensing of soil and vegetation. The characteristic features of metric classifi ers, parametric Bayesian classifiers and multiclass support vector machines are discussed. The results of classifi cation of hyperspectral airborne images by using the specifi ed above methods and comparative analysis are demonstrated. The advantages of the use of nonlinear classifiers are shown. It is also shown, the similarity of the results of some modifications of support vector machines and Bayesian classifi cation.
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Статья научная
The article considers the issue for development of the computer-aided program designed for determining optimal location of installation of symmetry facilities in 0.4 kV power supply systems with the motor-drive load in conditions of imbalance of voltages. The program is aimed at making electrotechnical calculations during designing, modernization and operation of electrical grids with available motor drive load. It ensures plotting of schematic circuits for 0.4 kV power supply system sections with installed symmetry facilities. The software program provides for calculating different symmetry options and selecting the most economically feasible one. Using the program in motor- drive load power supply systems will enhance the asynchronous motor reliability and efficiency. The program is of interest during development of the power supply system projects for the regions with available non-linear loads.
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Статья научная
One of the sources of environmental pollution with hazardous substances, primarily heavy metals, is the electroplating industry. The prevention of pollution of water bodies with wastewater containing heavy metal ions is closely related to reducing the consumption of fresh water for the technological needs of production and to reducing the amount of effluent. One of the solutions to this problem is to create low-waste and waste-free environmentally safe technological processes of wastewater treatment using treated effluents in the recirculation system, which reduces the negative impact on the environment. The results of studying the sorption properties of the natural modified mineral Akdolit-Gran prove a high efficiency of this sorption filling when conditioning electroplating shop effluents contaminated with a complex of heavy metals. Taking into account a relatively low cost of this natural mineral, Akdolit-Gran has the advantages in terms of its economic feasibility, plus the high degree of extraction of metals using this sorbent together with its low consumption allows designing recirculation systems for industrial enterprises meeting the requirements for physical and chemical parameters of service water.
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Статья научная
The article presents a reasonable method of calculating the angles of elevation of short radio waves with the influence of regular and random inhomogeneities of the ionosphere. The method calculates short radio waves (HF) through the horizontal inhomogeneous scattering ionosphere. The technique is based on application of the law of refraction of Snell’s for well-known models of the ionosphere and its evolution in the irregular parts. The description of the program to calculate the angles of radiation and reception HF is presented. The results of calculating the angles of arrival are compared with measurements of angles of arrival of HF. We obtained the best agreement between the experimental and the calculated resultsl of arrival angles of HF than for the regular ionosphere. The use of techniques is discussed in the article.
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The speed electromagnetic wave propagation in the snow-ice underlying surface
Статья научная
The results calculations the electromagnetic wave propagation velocity in the snow-ice cover depending on the density, the proportion liquid water content, and the propagation speeds the electromagnetic wave in dry snow, dry firn, and dry ice vary very markedly depending on the proportion liquid water content, the preferred orientation, and the shape ice and air structure are presented. The inclusions in the snow.The performed estimates the complex relative permittivity the medium that determines the speed propagation electromagnetic waves show a noticeable influence the density, the proportion liquid water content and the structure the underlying surface (snow, firn, ice), which allows identifying the layers the underlying surface in order to remotely determine the possibility landing a helicopter-type aircraft on an unprepared site with snow-ice cover.Shown, when the portion the water content in the medium is equal to zero, which is typical for negative temperatures, the speed propagation electromagnetic waves in the medium will depend on the density the medium and structure the dry ice in a small range of 1 m/µs temperature. In dry snow, vertically and horizontally elongated or spherical inclusions make a significant contribution to the change in the speed propagation the electromagnetic wave. At zero temperature, in the frequency range of 2 ... 8 GHz, the share water content in the medium, the density and structure the medium will play a determining role in the speed propagation an electromagnetic wave in the medium.The purpose this article is to determine the change ranges speed propagation electromagnetic waves in snow-ice the underlying surface depending on the density, structure, water content to restore the structure the snow and ice according to radar sensing, a more accurate determination the depth snow and thickness ice cover used in the assessment the possibility the safe landing an aircraft the helicopter type on an unprepared ground with snow-ice cover.
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The structure and magnetic properties of Fe-Mn-C alloy
Статья научная
The structure of intergranular borders in Fe-Mn-C alloy has been investigated. Importance of Fe-Mn-C alloys researches connecting with their wide use in machine industry as constructional materials. In this work an attempt to find out the physical nature of high shock viscosity of Fe-Mn-C alloy, mechanical and magnetic properties, calculation of intergranular borders electronic structure is made.
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