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  • Numerical experiments on the scattering of warm fogs by artificial droplets

    Various methods are used to scatter warm fogs: direct combustion of fuel in the fog; electric heating of the fog; introduction of streams or jets of warm and dry air into the fog; use of radiant energy for direct evaporation of hydrometeors; using explosions of highly heat-forming substances, etc. [4]. In this paper, artificially sprayed water droplets are used to scatter warm fogs. Refined calculations were made to investigate the possibility of fog scattering by artificial droplets. The model describes the fall of drops of radius r2 through the fog, consisting of drops of radius r1, the concentration of which is equal to n1. Detailed equations of gravitational coagulation are used taking into account the hydrodynamic interaction of droplets. The temporal characteristics of fog scattering (increase in visibility range) depending on the size of artificial droplets and their concentration are investigated. The size of artificial drops and their concentration, at which the maximum effect on fog scattering is achieved, are determined.

    Keywords: scattering of warm fogs, meteorological visibility range, concentration of fog drops, fog water content, artificial influence on fog

  • Modeling the diffusion saturation with carbon of austenite doped with chromium

    "Prediction of carbon concentration profiles depending on the cementation parameters is possible using mathematical models, most of which show good results for austenite Fe-C, without affecting the influence of alloying substitution elements. The paper describes modeling using the finite element method of the diffusion saturation of the austenite of the Fe-C-Cr system with carbon during cementation using 15Cr steel as an example, taking into account the influence of temperature, and also provides practical confirmation of the model. For the numerical solution of the problem, the COMSOL Multiphysics program was used. It has been established that for the one-stage cementation mode, the applied model of carbon diffusion in undoped austenite is in good agreement with the experimental data for austenite of the Fe-C-Cr system of steel 15Cr. For a two-stage process, the calculation of carbon concentration in the surface layer has a slightly larger deviation from the experimental data than at a greater depth."

    Keywords: carbon diffusion, COMSOL, final method, carburization, cementation, steel, diffusion, mass transfer, alloyed austenite, modeling, elements

  • The use of various criteria in solving an inhomogeneous minimax problem

    The article deals with the solution of the inhomogeneous minimax problem using genetic algorithms, as well as using several variants of the Plotnikov-Zverev algorithm. Three types of criteria for setting the function of assessing the fitness of individuals are described. The efficiency of genetic algorithms is compared with the Plotnikov-Zverev algorithm, using different criteria of the fitness function of individuals. According to the results of the computational experiment, it was concluded that the use of the quadratic criterion for the modified Goldberg model, using a two-point crossover, increases the efficiency of the genetic algorithm, and the accuracy of this solution is higher compared to the solutions obtained using modifications of the Plotnikov-Zverev algorithm.

    Keywords: schedule theory, inhomogeneous minimax problem, modified Goldberg model, genetic algorithm, minimax criterion, quadratic criterion, minimax criterion, cubic criterion, Plotnikov-Zverev algorithm

  • Formalization of regulatory and system-wide requirements for the curriculum of a typical university

    In this work, the author has compiled a list of requirements and corresponding indicators that must be taken into account in the process of creating the university timetable and estimates of the significance of each of these indicators are obtained. The task is to formulate directly the timetable formation procedure on the basis of the list of indicators and assessments of their importance. It is supposed to consider the possibility of solving this problem based on the use of its formalized model. To form a model, it is first necessary to formalize all the requirements from their list. There is considered an example of some of these requirements that briefly describe the procedure for their formalization.

    Keywords: higher education institution, timetable, timetable requirements, formalization, initial data

  • Numerical experiments on the scattering of warm fogs by artificial droplets

    The paper presents the results of numerical estimates of scattering of a dispersed medium (fog) using thermal and dynamic devices. Numerical modeling methods were used to obtain the results. On the basis of calculations, the use of different classes of combustible substances (kerosene, etc.) was analyzed for thermal dispersion, which is based on heating the air-drop medium to a temperature above the dew point, so that the drops that make up the fog evaporated. Technical devices of various capacities for pumping air from the zone of illumination, that is, using the method of dynamic scattering, are considered. The dynamic method is based on creating a flow of dry air located above the dispersed medium layer. In this case, the drier air coming from above or from the side causes the particles of the dispersed medium to evaporate, which leads to a decrease in its density.

    Keywords: dispersed medium, low layered clouds, thermal scattering method, dynamic scattering method, calorific value of substances, zone of enlightenment

  • Determination of critical stresses in shells of high flexibility

    The article is considered the wall stability of a steel cylindrical pre-stressed granary, compressed by the friction forces of grain and shell, taking into consideration the influence of the grain internal pressure, its elastic resistance from the inside and the elastic resistance of the pre-stressed shell outside. In this case, the initial and subcritical deflection of the shell is assumed to be axisymmetric, and the loss of the shell stability occurs with the formation of asymmetric deflection. The given solution of the problem allows to determine the magnitude of the critical efforts taking into consideration the influence of the grain internal pressure, its elastic repulsion, the magnitude of the initial deflections and the ratio of shell dimensions.

    Keywords: stability calculation, wall stability, prestressing, internal lateral pressure, elastic rebound

  • Analysis of functional completeness of health monitoring devices

    In today's world, health control is an essential element of everyday life. The article highlights the list of functional capabilities of various devices (smart watches, fitness bracelets) and describes the results of a formalized analysis of the functional completeness of health monitoring devices. On the example of two different sets of user requirements, two conditional systems are included in the study, by the degree of similarity with which it is possible to judge how the analyzed devices are suitable for this user.

    Keywords: Health monitoring devices, fitness bracelet, comparative analysis of functional completeness, pressure measurement, pulse, ECG, training monitoring, analysis of compliance with user requirements for devices, similarity of devices

  • Method for a measuring amplitude-frequency characteristics using a broadband signal

    The paper describes a method for a measuring amplitude-frequency characteristics using a random broadband signal as a test signal. The results of an experimental verification of the proposed method are given, as the hardware implementation of the meter.

    Keywords: measuring instrument amplitude-frequency characteristics, identification, Wiener-Hopf equation, discrete fourier transform

  • Mathematical modeling of pollution reservoirs by stationary sources

    This article analyzes the dynamics of pollution of water bodies (on the example of the Don river basin) by stationary sources for the period 2000-2015. using the methods of mathematical statistics, an empirical model is constructed to study the trend and fluctuations of pollution dynamics. For this purpose data of rosvodresurs of the Russian statistical Yearbook are used. The adequacy of the model for three-year forecasts with an error of up to 8% was checked. A system of differential equations describing the pollution process is derived.

    Keywords: mathematical model, statistical methods, trend lines, differential equations, prediction, model adequacy, the forecast error, the dynamics of pollution, water resources, waste water

  • Study of the heat transfer process in a liquid cooling system of a computer based on ferrofluids

    In this research the research problem of the liquid cooling system of supercomputer processors on nanomagnetic liquids by numerical modeling and the pilot study of processes of heat convection in the studied object is set. In article results of numerical modeling and the pilot study of process of the heat transfer are given in the heat exchanger of the liquid cooling system of supercomputer processors on the basis of nanomagnetic liquids, or ferroflyuid at influence of magnetic field impact assessment of magnetic field on the thermal resistance of the system and coefficient of heat convection the wall liquid Is made at different strengths of magnetic field. The numerical model of process of the heat transfer in the system the processor heat exchanger was investigated.

    Keywords: processor, thermal resistance, Laplace equation, liquid computer cooling system, ferrofluid, nanomagnetic liquid, heat transfer, heat transfer coefficient

  • Diffraction of a plane wave on a sphere made of metamaterial

    metamaterials, microwave, antennas, diffraction, Maxwell equations, electromagnetic waves, the dielectric constant

    Keywords: metamaterials, microwave, antennas, diffraction, Maxwell equations, electromagnetic waves, the dielectric constant

  • About increasing the availability of the default gateway in corporate networks

    Considered an important component of corporate networks - the default gateway. The main objective of the project is to minimize the time of convergence by ensuring high availability in order to ensure the continuity of the head office connection to remote offices. An analysis is made of the operation of one of the technological solutions, as well as estimates of the probability of failure-free operation for the default gateway with redundancy and without.

    Keywords: HSRP, fault tolerance, high availability, failure, convergence, routing, protocol, load reserve, redundancy, business continuity

  • Emotional attitudes of the students of Grozny: affective component

    The paper presents the results of measuring the overall emotional state of students in Grozny at the beginning of 2016. This characteristic is one of the indicators of social health of the study group, in particular, in relation to the political field. It is based on a pilot survey conducted among 141 students of the Grozny state oil technical University. By gender and national composition, the sample was approximately the same as in the entire educational institution. To measure the affective component of the emotional state, the method of the semantic differential of CH. Osgood was used. The interpretation of the results obtained was based on the Coombs ideal point theory, based on the proximity in the semantic space of the image of a real object from the images of ideal constructs. The distribution functions of the affective level of the emotional state are calculated in a linear approximation, as well as in the framework of the previously developed stochastic nonlinear psychosemantic phenomenological model. It was found that 14 % of respondents are characterized by a neutral emotional state, and 55% - positive. Of these, 33% reported their condition as slightly positive (a level of 0.1 to 0.3 on a scale of -1 to +1), and 22 % reported a steady positive (a level of 0.4 to 1). Negative emotional state was observed in 31 % of the respondents, of which 20 % - slightly negative (level from -0.1 to -0.3), and 11 % - stable negative (level -0.4 and below). The latter are the subgroup of risk in which social and political tensions can develop. The core of this subgroup is formed by 5 % of respondents who showed an extremely negative emotional state, with a level of -1. The results obtained differ slightly from similar data measured among students in Rostov-on-don around the same time period. For students of Grozny, the group of respondents with a positive emotional state is 10% more than for Rostov residents.

    Keywords: social attitudes, affective component, semantic differential, Coombs perception theory, linear approximation, distribution function, nonlinear stochastic model, risk group, social tension

  • Application of iterative calculus methods for analysis and simulation of instantaneous traction power supply schemes

    The article is devoted to the possibility of applying the methods of successive approximations in the analysis of the instantaneous scheme of the traction network. The described approach allows to improve the accuracy of modeling dynamic modes of traction power supply sections, and also allows to significantly improve the process of modeling diagnostic systems and control of electric rolling stock at the design stage based on a more accurate model of dynamically changing input parameters of the traction network depending on their required level.

    Keywords: traction network, instantaneous circuit, diagnostics, simulation, iteration

  • Simulation of the design activity diversification of innovative enterprise

    The main maintenance of a diversification of production as activity of subjects of managing is considered. being shown in purchase of the operating enterprises, the organizations of the new enterprises, redistribution of investments in interests of the organization and development of new production on available floor spaces. The most important organizational economic targets of a diversification of management are presented by innovative activity of the industrial enterprise.

    Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

  • Calculation justification of the method of using removable load-lifting devices when moving ellipsoid bottoms of nuclear power plant hull equipment

    A calculation for the strength and stiffness of a removable grip with a geometric closure for moving and turning ellipsoid bottoms of the steam generator is presented. The proposed design solution will improve the safety of operation of nuclear power plant hull equipment and reduce the labor and material consumption of technological equipment by eliminating the welded load-handling and installation elements

    Keywords: removable load-grabbing devices, turning and moving, plot of bending moments, calculation of stiffness, thickness of the grip

  • Systems for automatic generation of monitoring programs

    Models of monitoring program generation systems are proposed. to significantly reduce the cost of time and other resources for monitoring complex technical objects. Systems are considered at several levels: subsystems and modules, communication links, use cases, physical representation. A technique for adapting system models to subject areas.

    Keywords: complex technical object, monitoring, models of software systems, program generation

  • The model for overcoming the risks of destroying the life world of a young family (based on materials from the Rostov region)

    This article analyzes strategies to overcome the risks of a breakdown in the life of a young family. Based on the results of an empirical study conducted in the Rostov region, the authors of the article identify micro- and macro-strategies for overcoming the risks of destroying the life world of a young family within the framework of cognitive, value, and behavioral levels. The authors conclude that an important role in overcoming cognitive-value risks is given to microsocial strategies, where the family occupies key positions. Macro-social strategies are represented by the work of social institutions such as the state, the media, and education. According to the authors, the symbiosis of the selected strategies is the most effective for reducing the risks of the collapse of the life world of a young family.

    Keywords: Model, cognitive model, risks, strategies for overcoming risks, family, young family, life world

  • Evaluation of the effects achieved by focusing the electromagnetic field in the region in the microwave processes of grain processing

    Microwave plants are now widely used in industrial and agricultural processes. The main effects by using of focusing of methods in procceses of microwave proccesing of grain cultures is considered. Cereals are dissipative materials with a significant attenuation factor. Focused excitation allows to concentrate field intensity distribution near focusing point in planes parallel and perpendicular to aperture. The limit depth of effective focusing is determined. The dependence of the focus efficiency and the size of the focused area on the depth of the focus point location is also shown.

    Keywords: Microwave processing, focusing aperture, efficiency of focusing, size of area of focusing

  • Mathematical assessment based on the Lotka – Volterra method of quantitative indicators of processing straw raw materials during combine harvesting of grain

    During the harvesting of crops, a significant amount of straw residues is formed, which can be used as raw material for subsequent processing. To assess the volume of straw suitable for processing for various needs of the agro-industrial complex, it is proposed to apply the Lotka-Volterra method. Using this method, it is possible to predict the formation of straw residues depending on the initial indicators during harvesting.

    Keywords: straw residues, processing of straw raw materials, modeling, Lotka-Volterra method

  • Model of a system for protecting multichannel automated systems from ddos attacks, taking into account the release as channels are processed

    The paper provides an analysis of the principles of the multichannel protection system. The analysis showed that in order to solve the problem of ensuring secure communication with an external resource through public networks, it is advisable to use a multi-channel system with different channel capacities, while the main channel and spare channels that are connected to work when the main channel cannot handle all incoming applications with probability of 0.95. This model takes into account that the channels are filled hierarchically, and are freed up as the applications are processed.

    Keywords: automated system, modeling, protection subsystem, queuing system, probabilistic assessment

  • Analysis of the load curve in the isolated areas of power supply

    The article studies the subject of human settlements with decentralized power supply, included into a locally isolated power supply complex. The basic integrated measures were determined for settlements power lines daily load curves. The results are presented, for dependency assessment between the integrated measures for daily load curves and the number of the settlement’s inhabitants. The dependency has been proven to be effectively described by a second order equation. For the dependency, the correlation coefficient, the determination coefficient and the average approximation error have been given.

    Keywords: Power line load curve, decentralized power supply zone, locally isolated power supply complex, approximation

  • The algorithm for tumor localization in case of breast cancer according to microwave thermometry

    This work was carried out as part of research on the development of methods for the intelligent analysis of medical thermometric data. These methods are designed to create a consultative intelligent system for the diagnosis of breast cancer. We propose a new approach to the formation of a feature space based on microwave radiothermometry data that are designed to detect malignant tumors. In the process, about 200 new signs were obtained and tested. Based on them, we created an algorithm for the localization of tumors in the mammary gland. This algorithm is a weighted voting algorithm that is configured using a genetic algorithm. The resulting localization algorithm can achieve an accuracy over 70% in test samples.

    Keywords: microwave thermometry, breast cancer, mammology, tumor localization, accuracy, data mining, genetic algorithm, weighted voting algorithm, thermometric diagnostic features, cross-validation

  • Investigation of electromagnetic fields of the AC railroad section

    The article is devoted to the problem of determining the electromagnetic influence degree of electrified AC railways traction networks. The potential, induced by the field, can create a threat to life and health, create conditions for failure of low-voltage equipment, appear as a source of interference. This article considers some approaches to the calculation of electromagnetic field characteristics and gives a critical analysis of the methods used.

    Keywords: ice melting, calculated coefficients, selection of optimal parameters, traction power supply system

  • Modeling of software implementation of labor distribution management

    The paper considers a game-theoretic model for supporting the distribution of labor resources, i.e. To simulate the problem considered in the work, the mathematical apparatus of game theory was used. In this paper, two algorithms for constructing a solution are described and examined in detail for two models of transport tasks used to study the distribution of labor resources: static and dynamic. The authors describe the developed models, and then consider the structure of the solution to the problem. The paper considers a compromise solution in the models of the distribution of labor resources for the transportation problem. An algorithm for finding a compromise set and a description of the structure of the software implementation of models is given. The description of the models is formalized in the field of application to game theory, i.e., a game version of the problem is considered. Interpreting the problem, we consider a system consisting of players. Players in the constructed model strive, in addition to maximizing profits, to achieve a compromise between the participants. The role of compromise will be played by a plan of movement of labor resources, satisfying all participants. As a result, we obtain the transportation problem in a slightly modified formulation. These differences specify a new task and set a goal to solve it.

    Keywords: modeling, analysis, management, software implementation, game-theoretic models, distribution of labor resources