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  • Mathematical modeling of the magnetic field distribution in the vicinity of the erythrocyte

    Erythrocyte, when moving through a narrow capillary, stretches out and rolls like a tractor's caterpillar. Charges located on the surface of the erythrocyte, move together with the membrane and generate a magnetic field in the vicinity of the erythrocyte membrane, which can affect both elements of blood flow outside the erythrocyte, and its contents, in particular, the iron atoms that make up the hemoglobin. A three-dimensional model of the erythrocyte is constructed. The shape of the erythrocyte is approximated by a truncated cylinder of radius r with generators L1 and L2. It is assumed that all charges on the surface of the erythrocyte are the same and evenly distributed over the surface of the erythrocyte. Charges move along with the membrane along closed curves (trapezoids). Moving charge creates a magnetic field, the strength of which depends on the magnitude and speed of the charge. On the erythrocyte membrane there are several charges and each of them at some selected point creates a magnetic field. The total strength of the magnetic field is defined as the vector sum of the strains created by each of the charges. The following parameter values ​​were used in the calculations. The charge of the erythrocyte is 20 million elementary charges. The number of charges on the erythrocyte membrane is 38594. The rotation frequency of the erythrocyte membrane is 20 revolutions per second. The erythrocyte radius is 2 μm. The erythrocyte volume is 94 μm3. The erythrocyte surface area is 135 μm2, the lengths of the truncated cylinder forming are 3.4 μm and 11.5 μm. The erythrocyte speed is 100 μm / sec. The step along the space is 0.1 μm. The performed calculations of the magnetic field strength H have shown that the rotation of the erythrocyte membrane with the charges placed on it leads to a significant redistribution of the magnetic field in the vicinity of the erythrocyte. And with an increase in the frequency of rotation of the erythrocyte membrane, the heterogeneity of H increases significantly and can lead to a change in hemodynamics in the microcirculation system.

    Keywords: mathematical model, erythrocyte, narrow capillary, magnetic field, microcirculation

  • On one method of solving the operational planning problem on a situational network

    In this paper, we consider the task of constructing a work plan in the form of a chain of control actions that change the system, and methods for solving it. The problem of finding the optimal path on the situational network is constructed with a mathematical description of the initial conditions and the requirements for the result. Briefly describes the standard solution of this problem: the method of fuzzy products. The main problems of the fuzzy product method are considered. The solution of the task of constructing the chain of actions of an operator on a situational network using the dynamic programming mechanism is described. A combined method is proposed for finding chains of actions with procedural construction of a situational network using the dynamic programming method with constraints. The first step and step l of the algorithm for solving this problem are described. The advantages of this method over other.

    Keywords: situational modeling, fuzzy sets, graph theory, decision theory, documentation, complex systems, fuzzy logic, fuzzy situation networks, set theory, optimal control theory, dynamic programming

  • Application of methods of data mining in the development of the system of classification of students' competencies for the university web-site

    The article is devoted to the problem of using artificial neural networks as one of the methods of data mining (intellectual data analysis) for classifying the competencies of university students when determining the educational specialization. It describes the complexity of the process of selecting specialization and the associated negative consequences, as well as an approach to solving the given problem using software classification tools. As a basis for the implementation of the proposed tools, the student's information system is used on the website of the University of Tartus, Syria. The article presents data selection criteria to form the training sample, which includes the academic performance in some courses as input vectors. The values of the output vector depend on completed specialization and it get into the training set only if it is properly selected. On the basis of these data, the structure of a multilayer artificial neural network is formed and the learning algorithm is selected, the results of which are reflected on the university's website in the form of advice on the choice of future specialization, which has allowed increase the effectiveness of the educational process.

    Keywords: Data mining, artificial neural network, web-design, machine learning, classification

  • 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: differential equations, perfect mixing cell, dynamics, model, material balance, state of equilibrium, nonstationary process

  • Investigation of the frequency of wave oscillations in a liquid layer on the porous foundation

    In work is considered numerical solution of a task about distribution superficial waves in a liquid layer on the porous basis. Expressions for the decrement of attenuation and frequency of fluctuations of a wave are written. Dependences of frequency of fluctuations of a wave on dimensionless sizes are shown. Various special cases are considered. The dispersive equation for the infinite thickness of a layer of the porous environment is written.

    Keywords: porous environment, frequency of fluctuations of a wave, decrement of attenuation of fluctuations of a wave, rhombohedral packing of balls of the porous environment

  • Design of the portal for the management of the" South-Western deanery " of Rostov-on-Don

    A business simulation of a social project-a portal for the management of the" South-Western deanery " of Rostov-on-don. The first stage of the Life cycle – analysis of the subject area using CASE technologies is considered. UML language and Rational Rose design platform are used.

    Keywords: pilgrimage trips, virtual tour, information system design, object-oriented approach, Rational Rose, UML, business use case diagram, Use case diagram, activity diagram

  • The equipment movement registration in the auto road sector.1. Analysis.

    The process of creating an automated information system for organizations working in the road sector using CASE technologies is described. The first stage of the Life cycle – analysis of the subject area in the aspect of modeling business processes associated with the acquisition, maintenance, movement and verification of devices and equipment is showh. Charts are presented: business use cases, use cases and UML activities.

    Keywords: instrumentation, equipment, measurement, testing, metrological verification, object-oriented approach, activity diagrams, use case diagram, Microsoft Visual Studio 2012

  • The effectiveness of using a comprehensive testing program

    The introduction of the comprehensive program "Boundary control" is considered on the example of a control and experimental group. The results of the effectiveness of this complex have been proved practically and theoretically: the progress of cadets has increased, and calculations of statistical estimates have shown that the calculated value is less than the critical one. That is, it can be concluded that the differences in the estimates between the experimental and control groups are statistically insignificant at a given significance level. That is, for comparison, approximately equal in knowledge two groups were taken.

    Keywords: Student's criterion, mathematical statistics, representative sample, experiment, group sampling, expert assessments

  • Analysis of aggressive behavior in the context of problem family violence

    This scientific research presents the results of a survey among a population of 18 to 64 years old, of which 18 men and 32 women. A total of 50 people were interviewed. The subject of the study is family violence, the subject is the aggressive behavior of respondents in the family. Objective: to analyze the aggressive behavior of respondents in the context of the problem of family violence through a sociological survey and data processing in the PSPP program. With the help of the semantic differential, we learned the level of emotional attitude to the friendly families without conflicts, to families with conflicts and to their real family. Respondents on the proposed grounds assessed their emotional attitude to different types of families. A semantic portrait was made and primary distances were found. Mostly, 68% of respondents believe that there is a problem of violence in families, 12% do not think that there is a problem, 10% do not know, 6% and 4% do not know and do not think about it. The majority of respondents - this is 76%, quarrels in the family are rare, 10% - often, 2% - very often and 12% never.

    Keywords: subjective perception, emotional states, questioning, distribution functions, comparative analysis, semantic differential, conjugacy tables

  • The internal structure of the affective components of family attitudes

    The work is devoted to one of the indicators of hidden family aggression – emotional components of family attitudes. The research is based on the pilot measurements carried out by the survey using the method of semantic differential. A total of 50 people were interviewed, including 18 men and 32 women, aged 18 to 64 years. The option with calibration was used, and respondents were asked to characterize on a semantic scale the real families and both ideal positive and negative ones. Images of ideal constructs defined in semantic space the scale and direction. In accordance with Coombs's "ideal point" approach, the level of emotional perception was estimated by us from the relative distances from the image of the real object to the images of ideal constructs. Analysis was performed for each respondent separately, and based on the results the distribution functions of emotional perception by respondents were built. They reflected the internal structure of the group for affective components. The calculations were performed in the linear approximation (for half-difference of the above-mentioned relative distances) and within the framework of the non-linear psychosemantic phenomenological model. In the last the levels of perception are given in the form of differential equations, which were solved by the Monte Carlo method with by AnyLogic multi-agent simulation package. The obtained results confirm the earlier estimates based on the averaged data. The average value of the level of emotional perception throughout the study audience is positive (0.33 on a scale from -1 to +1), which indicates the absence of aggressive behavior for the majority of respondents. A strongly negative level (from -0.5 to -1) showed only 6%, against this background, they can develop aggressive behavior. Another 6% are characterized by a slight emotional irritation in the family sphere (the level from -0.1 to -0.3), this is an intermediate group which under adverse conditions can develop into a risk group. For the rest of the study audience (88%) emotional relationships in the family are not aggressive, positive.

    Keywords: semantic differential, subjective perception, latent variables, psychosemantic phenomenological model, emotional perception, multi-agent modeling, distribution function

  • Translation of geometric models of geodesic shells in a neutral format SAT

    The description of information exchange methods between CAD and CAE systems is presented. The description of the modular system of design and strength analysis of geodesic shells GeoTran is given. Translation of geometric models from ArchiCAD to Patran/Nastran/Patran has drawbacks. It is proposed to implement the translation of geometric models in a neutral SAT format. Developed a translator geometric models of single-contour geodetic shells from ArchiCAD in SAT format. The translator allows you to automate the exchange of information between the CAD system ArchiCAD and various CAE systems designed for strength analysis.

    Keywords: data exchange between CAD and CAE systems, neutral file, SAT and OBJ formats, geodesic shells, translation of geometric models

  • Calibrating the triaxial accelerometer according to a number of measurements with different orientation

    The problem of calibration of a three-axis acceleration sensor is considered. A number of measurements obtained with the sensor at its different orientations in space are used as initial data for calibration. It is assumed that the sensor is stationary for each orientation variant. The measurement data are averaged at each static sensor position, and the averaged results are used as parameters in a system of nonlinear equations that are solved by the Levenberg-Marquardt method. The results of the proposed method in the article are presented in the experiment with a real sensor, which allows to check its effectiveness.

    Keywords: three-axis accelerometer sensor calibration, the sensor coordinate system, the coordinate system of the gravitational field, the rotation of the coordinate system, the matrix of coordinate transformation, the correction factor, the average value of the me

  • System of automatic diagnostics of pumping units with centrifugal pumps

    The article deals with the parametric method of pump unit diagnostics. The well-known methods of diagnostics are described, the comparison of methods is given. The parametric method allows to determine the current state of the pumping unit on the basis of publicly available information in the process of liquid pumping. The article presents a mathematical model of the system frequency Converter, engine, pump. An example of changing the coefficients of the diagnostic model is given.

    Keywords: centrifugal pumps, methods, diagnostics, parameters, mathematical model, coefficient, diagnostic models

  • On the neutral loading of a disk under thermal and force influences

    A thin circular disk is considered, the material of which exhibits elastic and plastic properties under thermal and force influences. In the central part of the disk, the temperature field is uniform. At the boundary of the disk, pressure and a constant temperature are set. Approximation of a plane stress state is adopted. The additive form of the connection of full, elastic, plastic deformations and deformations under free thermal expansion is considered. Elastic deformations are expressed in terms of stresses according to Hooke's law. A linear approximation of the dependence of the plasticity limit on temperature is proposed. The possibility of neutral loading of the central region of the disk and its external boundary is shown. Especially distinguished is the condition for the plasticity of Tresca.

    Keywords: mathematical modeling, elastoplastic body, plane stress state, piecewise-linear plasticity conditions, plastic flow theory, thermoelastic plasticity

  • Modeling of the automotive radar performance in autonomous driving applications

    An approach to real time modeling of automotive FMCW radar performance in autonomous driving applications is proposed. Simplified model of driving situation and model of reflected signal are developed on the basis of commercial automotive radar performance. Complex solution for radar sensing modeling was produced. Modeling results are represented.

    Keywords: autonomous car, computer vision system, modeling, automotive radar, scattering centre, Fourier transform, radar image

  • On the behavior of an elastoplastic disk under the action of a thermal source

    The steps of constructing an algorithm for calculating the stressed and strained state of a thin circular disk experiencing thermal and force effects are discussed. A homogeneous temperature field is created in the central part of the disk. Within the framework of the theory of the flow of an ideal elastoplastic body, conditions of general plasticity are considered. It is assumed that the plasticity limit for uniaxial tension is common for all plasticity conditions. Dependencies between the disk radius, the temperature of the central region of the disk and the external pressure, which determine the appearance of plastic regions, are established. For piecewise-linear plasticity conditions of general form, analogous dependences are defined, when singular plasticity regimes are realized at elastoplastic boundaries. For different values ​​of the input parameters of the problem, the stresses, equivalent stresses and the hodograph of the stress vector are given.

    Keywords: mathematical modeling, elastoplastic body, plane stress state, piecewise linear plasticity conditions, plastic flow theory, thermoelastic plasticity

  • New method of investigation fast fracture of smartphone screen

    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: velocity of crack propagation. Gorilla Glass, fast fracture, Sapphire, displacement of deformed bodies,

  • Information technology of three-dimensional visualization of measurement data and numerical modeling data

    The paper presents a description of the developed software for three-dimensional graphics, which is designed to interpret a wide range of geophysical information and modeling data. Information technology is used to visualize data of radar observations of clouds, the results of numerical simulation based on a three-dimensional cloud model. Some features of the program are given. The fixed radar reflectance scale makes it easy to change the display threshold and explore the internal structure of the object sequentially by looking at the nested layers one after another. The functions of creating of horizontal and vertical sections of the object is provided. The program is created using open library OpenGL modules.

    Keywords: application software, three-dimensional visualization, cloud parameters, radar reflectivity, simulation data

  • Development of UAV mathematical model on quadrotor frame DJI F-450 basis

    In article the UAV three-dimensional mathematical model on the basis of the quadcopter as most the UAV widespread type at the moment is developed. The quadcopter is based on a frame of DJI F-450. The first part of article is devoted to the mathematical description of the quadrotor model, namely: to a kinematics and dynamics models; to forces and torques operating on the UAV; to rotation matrixes; to the assumptions simplifying mathematical expressions. For the description of location and movement of the quadrotor in space also the bound will be used inertial reference frame. Therefore transformation from one frame to another is necessary. The simulation of the operation of the motors 1-4, which are electric drives of direct current, has been performed. Rotation of engines is transferred to screws directly. Movement of the quadcopter in the bound frame is considered in the article by the accounting of the models of a kinematics and dynamics describing the vehicle movement.

    Keywords: quadrotor, UAV, kinematics, dynamics, 3D environment, DJI F-450, engine, traction, rotation matrix, vehicle

  • Interaction of few-cycle optical pulses in thin film of topological insulator

    The aim of the paper is to investigate the interaction of two such pulses when they propagate through the sample. The urgency of few-cycle pulses study is associated with a large number of possible practical applications in various fields of science and technology (from medicine to the study of ultrafast processes). The modeling of the electromagnetic field evolution based on the Maxwell`s equations supplemented by an equation determining the behavior of the electric current in the system. Electrons were described in the long-wave effective Hamiltonian in the case of low temperatures. As a result of the study, the dependence of the shape of the few-cycle optical pulse on its initial velocity and initial amplitude was revealed. When a pair of few-cycle optical pulses interacts in the film of a topological insulator, several new pulses are formed. After a collision, they begin to propagate fairly stable with conservation of the acquired amplitudes. The effect, associated with the steady spread of pulses after the collision, may be useful in the development of hybrid devices based on the effect of light interaction with electrons of the topological insulator.

    Keywords: few-cycle pulses, topological insulator, collision

  • Model and software package for study of asymptotic form of velocity vector components of rotating stratified liquid

    The software package, realizing the calculation and graphics visualization of asymptotic behavior at big time of dominant terms of velocity vector components at 2D motion of rotating stratified liquid, is developed. The mathematical model, which lies at the basis of the software package, is presented. The structure of the software package is described. The application of the software package in the study of fluctuations in stratified fluid is shown.

    Keywords: stratified rotating liquid, mathematical model, software package, asymptotic behavior, dominant terms of the asymptotic forms

  • Controlling the characteristics of strontium and calcium vapor recombination lasers

    Possible methods of high-speed control of the output characteristics of recombination He-Sr and He-Ca lasers using mathematical models are analyzed. The capability is demonstrated of wide-range control of laser output characteristics with the help of two methods – by varying the amplitude of the additional current pulse imposed on early afterglow of the pulse-periodic discharge and by varying the moment of this pulse imposing. The dependences of the laser output characteristics on the parameters of the additional current pulses are numerically calculated. The mechanism of their influence on the population of laser levels is established. The results obtained make it possible to purposefully form control current pulses for the recombination metal vapor lasers.

    Keywords: recombination metal vapor laser, He-Sr-laser, He-Ca laser, gas-discharge plasma, fast controlling, mathematical modeling

  • Optimization of heterostructure thickness of perovskite solar cells using numerical modeling

    Numerical physical-topological modeling is carried out to optimize the thickness of perovskite solar cells on the basis of the heterostructure TiO2 / CH3CN3PbI3-xClx / Spiro-OMeTAD. The results of the conducted studies showed that the optimum values ​​of the thicknesses of TiO2 and CH3CN3PbI3-xClx heterostructure films, which make it possible to obtain a high coefficient of efficiency of the solar cell, lie in relatively narrow limits. The carried out researches have shown the possibility of effective use of numerical physical-topological modeling for the development of perovskite solar cells, taking into account the features of photogeneration, recombination and transport of charge carriers in real heterostructures.

    Keywords: Solar cell, perovskite, titanium dioxide, heterostructure, numerical simulation.

  • Investigation of the efficiency of the heat sink surface of a volumetric body with an internal heat-loaded source in an aerodynamic flow

    In this work, a study was made of the efficiency of the heat sink surface of a volumetric body with an internal heat source. An electrostatic analog of the distribution of the thermal field is chosen. A model of the convective flow is proposed, under certain initial and boundary conditions, the thermal conductivity of the medium transforming into heat removal. The conclusion is made about the ineffectiveness of the heat-conducting surface in the form of whip, finned and other designs of existing heat sinks, increasing only the mass, technological complexity of manufacture, thermal resistance and temperature of the heat-loaded element.

    Keywords: Temperature field, convective heat transfer, effective heat sink area, electrostatic analog, similarity theory

  • Model for optimizing the tuning coefficients of a firmware measuring channel

    When developing large information-measuring and control systems, special attention must be paid to the interaction of various blocks of the system with each other. For example, the structure of a software-hardware measuring channel consists of four consecutively connected elements: primary converter; analog-to-digital converter; software dynamic converter; digital to analog converter. To find the parameters of the measurement channel error, mathematical models were constructed for each of the blocks. Simulation modeling of the measuring channel was carried out. As the input signal, the first-order aperiodic link model is taken. To generate the interference signal, a random number generator with a noise level of 0.5 is used. The error for the measuring channel is found. The suggested mathematical model allows to find the tuning coefficients of the software of the measuring channel, which ensure the minimum information loss in the software-hardware measuring channel. The resulting model can be used in automatic control systems for the current identification of regulator settings.

    Keywords: model of measuring channel, model of primary converter, adjustment of coefficients, error of measuring channel