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A mathematical model of the frequency detection signals of nonlinear devices and mathematical modeling of the quadrature power amplifier frequency-modulated signal under the influence of harmonic interference on the non-linear reinforcing elements of the device are presented. Assess the degree of reduction of intermodulation oscillations in a narrow frequency band of the output signal of the quadrature...
Digital image processing is used in various spheres of production, medicine, as well as for laboratory researches. Many technical and scientific problems are solved successfully. One of the such problem is percolation (impregnation) — the theory what describes the appearance of infinite connected structures consisting of elements. This theory is used in field of capillary-porous material, such as...
The article substantiates the relevance of the conducted research and determined the scope of application of the developed algorithm. Private problem of identification of tubular products and slabs at Vyksa Steel Works is considered. The article shows analysis of modern developments in the field of localization and identification markings of industrial products. It shows the description of the localization...
Data can be stored in the traditional ER-databases or in the hierarchical form. We propose a mathematical approach to formalization of OLAP cubes indicating the relationship between those OLAP cubes and corresponding ER-model for a concrete database. The OLAP cubes approach is constantly developing and supplemented with new algorithms, thus, leading to significant discrepancy in the main concepts...
In order to ensure reliable and uninterrupted electric power supply for electric power users it is necessary to properly build an electric power supply system, and in particular to minimize electric power losses during its transmission from the generation source to the users. One of the solutions is to design the structure of uninsulated cables rated for 6–35 kV voltage class transmission with increased...
Spherical surfaces are utilized widely in precision bearing, MEMS and parts of precision engineering. Constantly growing needs in the high motion performance of spherical parts, sphericity error is becoming an indispensable component in the control of form error. However, currently the quality control of a spherical surface is restricted by the lack of science-based mathematical models. This paper...
Improving the efficiency of the third generation solar cells, containing semiconductor quantum dots (QD) as components, is associated with the obtaining of nanoparticles with controlled parameters. Micellar synthesis method has certain advantages providing the obtaining of nanoscale monodisperse particles. In the reverse emulsion of bis (2-ethylhexyl) sodium sulfosuccinate (AOT)/n-hexane/water the...
The results of integrated baluns design are presented. The designed baluns are subjected to use in monolithic integrated circuits and system-on-a-chip fabricated by SiGe BiCMOS technology. The results of electromagnetic simulation shown that designed balun has a rather low insertion loss and good matching.
The article presents the results of the design of 1–7 GHz linear amplifier schematic based on HBT (0.25 um SiGe BiCMOS SG25V IHP manufacturing process) with a genetic-algorithm-based software tool for automated structural and parametric synthesis Geneamp. The advantages of the developed amplifier are: wide bandwidth (overlap L, S ranges and partially C-band); good matching level at the input and output...
The article compares the results of X-ray diffraction, electric and magnetic studies, as well as the heat capacity of samples of solid solutionsV1−xFexO2 and V1−xAlxO2 and the same samples after their long storage at ordinal conditions. The appearance of reflexes, allegedly belonging to the phases of V2O5 and iron oxide (aluminum), was fixed by the X-ray diagrams of “stored” samples. It was found...
Coherence of possible control loops is an important issue in power facility management. In wind power engineering, under the instability of wind energy and the possible presence of more than three control loops influencing on wind turbine performance, there is a problem of prioritizing operation of controllers. The method of paired comparisons proposes as an alternative technique of prioritizing control...
The actual synchrophase electric drive (SPED) control methods are built with a number of assumptions. Therefore the methods are full of flaws. The known time quasioptimal control method is based on the acceleration constancy assumption. It makes the phasing process inaccurate. Additional phasing process is needed. Phase plane method, control theory, electrical machines theory is used in the work....
This work is about imitating modeling of functioning technology of two LAN organized on the basis of AsteriskNow, presented as two knots divided among themselves by a certain distance with use of the software package into NetCracker 4.1. Development of the imitating model consisting of two or more knots removed on distance from each other and definition like a traffic between knots, parameters of...
The article describes the ArGIS — geoinformation system for archaeological objects. Archaeological objects and their attributes are considered. Constructed the feature space based on archaeological object attributes. Applied clustering techniques and methods for constructing association rules for the archaeological objects, as points in feature space. Developed modules for visualizing results of data...
Tasks of obtaining and usage of exact cumulative expected values of some indecies of a network's structural reliability, such as k-terminal probabilistic connectivity, average pairwise connectivity and expected size of a subnetwork that contains some special node are considered in the paper. Random non-oriented random graph with reliable nodes and unreliable edges that fails independently is used...
An effective operation of data measuring systems is not possible without the timely metrological calibration of measuring channels. Uncertainty of information imparted by uncalibrated channels leads to ineffective monitoring and wrong performance decision making. The reviews on advanced researches in the field of measuring channels calibration show negligible exploratory activity in the field and...
Issues of building power consumption forecasting techniques is paid a lot of attention because of it depend many indicators of the effectiveness of a single electricity retail company and, ultimately, the tariff for customers on the market price formed on the day-ahead market (DAM). The aim of the research is the spectral analysis of retrospective data of “Omsk Energy Retail Company” at various intervals...
The results of the research of magnetic field of hybrid magnetic system consisting of a Π-shaped electromagnetic iron separator and knife-like form concentrators. These magnetic systems are used in the food industry, agricultural processing enterprises, concentrating mills, thermal power plants, factories of building materials industry, coking plants for extraction of ferromagnetic particles from...
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