The main problem is to determine the bandwidth of the power cable system (PCS) through monitoring of the thermalfluctuation processes cable. Investigated the temperature field in the cross section of the cable in accordance with the theory of heat conduction. The results of studying the thermal conductivity of the PCS. In Matlab, using the system equations Fourier transform in the cylindrical coordinate system is built, the temperature gradient in the cross section of the cable and the environment. On the basis of the thermalfluctuation theory to examine the process of destruction of insulation by thermal vibrations of the atoms, with the partial discharges (PD). The study of failure-free operation of the insulating material PCS. Determined the probability of occurrence of the CR in dependence on influencing factors (temperature, insulation, number and size of inclusions). The distribution of the probability of occurrence of the CR in dependence on a value of density inhomogeneities insulation (y) and the energy of rupture of chemical bonds (D).
Keywords: forecasting, aging of insulation, partial discharges, thermalfluctuation theory
The article deals with the movement of erythrocytes along the narrow capillaries with a diameter smaller than the erythrocyte diameter. Red blood cell in narrow capillary has tank-treading motion. The erythrocyte rotation frequency reaches several dozen revolutions per second. Electric charges located on the surface of the erythrocyte, move together with the erythrocyte membrane and create a magnetic field in the surrounding space. A two-dimensional model of erythrocyte movement along narrow capillaries was constructed. If the erythrocyte surface area and erythrocyte charge are known, then the density of charges on the erythrocyte membrane can be determined. The magnetic field strength of a moving charged particle can be determined if the particle charge, the particle velocity, the distance from the particle to the point at which the magnetic field strength is determined, the angle between the direction of the particle velocity and the direct connecting particle, and the point at which the tension is determined are known. The total strength of the magnetic field of several moving charged particles is defined as the vector sum of the magnetic field strengths of the individual moving charged particles. In the two-dimensional model it is assumed that the red blood cells are rectangles that move along the capillary, and the erythrocyte membrane is the sides of the rectangle. Discrete charges are located on the sides of the rectangle and move either clockwise or counterclockwise. It is possible two variants. Their membranes either rotate in the same direction or in opposite directions. Calculations were carried out for both variants and at different rates of rotation of erythrocyte membranes (from 0 to 50 revolutions per second) and distances between red blood cells. It is shown that at distances between erythrocytes smaller than the two capillary diameters, the influence of neighboring red blood cells can be neglected (the difference is less than 3%).
Keywords: "mathematical model, magnetic field, erythrocytes, narrow capillaries, magnetic field strength "
The article deals with the issues of impact interaction of particles with layers of dispersed material of different thickness. The influence of the interaction velocity and the thickness of the substrate on the appearance and structure of the collision result is investigated. It is established that at low speeds there is a crater formation while the particle is on the substrate surface. With the growth of the interaction rate, the formation of a crown is observed, and particles penetrate into the substrate material. Experimentally determined the values of the velocity and thickness of the substrate, corresponding to the beginning of the formation of the crown.
Keywords: particle, blow, flow, splash, reflection, speed, stream, the bulk material flow, the recovery factor of speed, the substrate
The article is devoted to topical problems of modern construction - creating a comfortable environment for people in the premises and in the areas of construction by studying and researching the heat-wind processes in the city canyon. Particular attention should be paid to the role of insolation in the formation of the heat-wind regime of the canyon space, which is the determining factor of the thermal regime of the buildings and the building area.
Keywords: urban canyon, insolation, buildings, solar radiation, heat balance, radiation balance
The problems of young families are analyzed. The relevance of the study of the social welfare of modern young families is shown. A cognitive model of achievement and stabilization of the social welfare of a young family was constructed on the basis of the results of the study ""The Life of a Young Family in the Rostov Region"", 2017. It is shown that the basic model of achieving social well-being is a two-loop scheme with positive feedback. Each of the contours of which corresponds to the basic characteristics: socio-cultural and economic well-being. The principal problem of the factor of satisfaction of needs is revealed. The necessity of creating a full-fledged monitoring system of the socio-economic level of a young family included in the social policy framework of the state is shown.
Keywords: young family, social welfare, system characteristic, cognitive modeling, model, two-circuit scheme, feedback
The article examines the organizational and technical aspects of detecting leaks and unauthorized taps as an important area of safety of oil pipelines. Priority to the timely detection and prevention of leaks and illegal taps in oil pipelines is the improvement of technical methods of detection.
Keywords: oil pipelines, safety, leakage, unauthorized tapping, warning, technical methods
The paper is considered modelling the process elaboration of a pit for high-rise building in the case of dense urban area. The research is analyzed stress strain state of soil with retaning wall. The authors are developed various design solutions of the retainig wall to decrease of displacement of the nodals in soil finite element model. According the results, it has selected rational design solution of retaining wall.
Keywords: dense urban areas, retaining wall, finite element method, stress-strain state, soil massif
Way of implementing pipelined processing of substances using broadband focused aperture were considered in this article. The model of this installation was created and calculated in the software package CST Studio Suite.
Keywords: microwave, broadband aperture, processing, focused aperture
The cryptanalysis task with use of new model of optimizing strategy – the combined bioinspired algorithm is considered. Application of the combined bioinspired algorithm (a genetic algorithm and an algorithm of ant colonies) for realization the cryptanalysis of shifts codes is described. The description of the combined algorithm is provided, his distinctive features are noted, the demonstration example of realization the cryptanalysis the ciphered text line is described by this algorithm. In relation to this algorithm it is shown that the probability of receiving an optimal variant of the decision at realization of combined cryptanalysis algorithms can't be less probability of obtaining the optimal solution when using of the classical bioinspired algorithms.
Keywords: Cryptanalysis, the bioinspired algorithms, genetic algorithm, algorithm of bee colonies, a crossingover, a mutation, the code of shifts
An experimental study of the resolving power of the rank detector of single pulses was carried out. Experimental dependences of the probability of detection- resolution of two pulses on the time position from the delay between the pulse fronts-are obtained. It is shown that the probability of correct detection - resolution reaches the value P101 = 0.5 with a signal-to-noise ratio = 2 for a delay between fronts of about 9,7 μs, and for a signal-to-noise ratio of 4 with a delay between fronts of about 9,1 μs.
Keywords: Rank detector, resolving power, probability of correct detection-resolution, signal-to-noise ratio, experiment
Based on the analysis of published in the open press the results of a large number of scientific studies on the development of reinforcement methods for strenghtening reinforced concrete structures, the rationale for the need to apply and the prospects for the development of a new method for their enhancement associated with the use of composite materials is given. The actual directions of additional experimental studies are proposed with the aim of improving the regulatory framework in Russia in this area.
Keywords: steel, concrete, reinforced concrete, composite material, strengthening, strength, reliability
An approach to assessing the safety of road traffic in the context of emergencies is developed based on an integral indicator of traffic safety, the use of which allows taking into account various factors affecting safety
Keywords: traffic safety indicators, emergency situation, traffic safety assessment, road, integrated indicators
Background: The quality of electricity is one of the main problems necessary for the normal functioning of responsible technological processes in which a slight distortion of the supply voltage can lead to a violation of the normal operation of enterprises. There are several solutions to this problem: uninterruptible power systems, fast automatic power reserve technology (FAPR), dynamic voltage distortion compensator (DVDC). The most interesting solution is the application of dynamic voltage distortion. Material and methods: The principles of constructing a dynamic voltage distortion compensator with multilevel voltage inverters are investigated. An imitation model constructed under the following assumptions is proposed: an ideal case of the main circuit system (without higher harmonics) is considered, the nonlinearity of the transformer is not taken into account, short-circuit currents are absent, only constant load power is used. Assumptions are justified by the fact that in practice their error is no more than 3-5%, which is permissible. The results are obtained by modeling the system in the MatLab 2016b package. Results: A fundamentally new structural and functional scheme of a dynamic voltage distortion compensator with a multilevel system is developed. The requirements for the dynamic compensator of voltage distortion, load, LC-filters, current-voltage transformers and a converter are determined. Simulation of the simulation model has shown that the system works and corresponds to the expected results. Conclusions: The proposed voltage compensation system will solve the problem of the normal functioning of technological processes. The simulation results showed that the declared functional of the DVDC provides compensation of the voltage level in a given range of voltage dips. The obtained results can be used to stabilize the power supply: in the power supply systems of medical institutions, electric transport, critical energy facilities of a high category.
Keywords: Dynamic voltage distortion compensator (DVDC), automatic control system, operation modes of DVDC, model of the DVDC system, multilevel voltage inverter, simulation model, voltage distortion, volt-additional transformer, electric power, voltage failure
The research that results from the work presented is the means of transforming space imagery. A transformation method based on the use of projective geometry methods is proposed. A completed study of the proposed method for mathematical image and terrain models showed a high degree of accuracy and a number of advantages over traditional image transformations
Keywords: Photogrammetry, transformations, cosmic images, projective geometry
The problem of formalizing the elastic line of a thin steel strip of great flexibility arose in the process of creating elastic elements with a nonlinear characteristic for use in various kinds of damping devices. Such elastic rods experience large displacements when the material operates within the elastic range, in particular when axial loading in the supercritical region, when the axial load exceeds the Euler force, but in the subcritical region the movements are not significant enough to obtain a regressive-progressive characteristic.The paper investigates the possibilities of softening the elastic characteristics under axial loading in the initial period by applying a rigid cantilever arm mounted on the end of the elastic rod with a vertical load applied to it. Simultaneously, the influence of the vertical force on the elastic characteristic of the circular trajectory is investigated. To formalize the stress-strain state of a thin steel plate of great flexibility, the method of elliptic parameters is applied. The resulting elastic characteristic actually has a regressive-progressive character. The results obtained using the ANSYS computation complex for a system with given geometric parameters correlate quite well with the theoretical dependences derived. It follows from the diagram that the eccentric compression of the elastic element forms a regressive part of the elastic characteristic, and the circular trajectory of the point of application of the vertical force forms a progressive section.
Keywords: elastic line, thin strip, greater flexibility, formalization, off-axis loading, elliptical parameters, regressive-progressive characteristic