Scientific Journal of KubSAU

Polythematic online scientific journal
of Kuban State Agrarian University
ISSN 1990-4665
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527 kb

SIMULATION OF LARGE-SCALE TRANSPORT NETWORKS USING METHODS OF MULTICRITERIA OPTIMIZATION AND TAKING INTO ACCOUNT STRUCTURAL DYNAMICS

abstract 1201606111 issue 120 pp. 1686 – 1705 30.06.2016 ru 918
In the article we present a spatial structure of largescale transport systems. The model of a transport network can be presented in the form of a graph, with a set of the nodes corresponding to elements of a network and a set of edges – to sections of roads the connecting these nodes. As the model of a card of roads, it is offered to use prefractal graphs which naturally reflect structure of communications when reviewing a transport network in different scales (the states, regions, areas). Prefractal graphs allow describing structural dynamics of the studied system in the discrete time. One of the most widespread scenarios of structural dynamics is the growth of structure. The statement of tasks of the organization of transport routes contains requirements criteria to finding of optimal solutions. Often these requirements and criteria are contradicting each other. It leads to appearance of a multicriteria problem definition. The multicriteria problem definition on a class of prefractal graphs is considered. The optimum algorithm of separation of the greatest maximum paths by the given criterion is constructed and estimates by remaining criteria are given. In operation computing complexity of the constructed algorithm of separation of the greatest maximum paths on a prefractal graph is calculated and advantage of operation of algorithm on last before algorithm of separation of the greatest maximum paths on normal graphs is justified. The constructed algorithm on prefractal graphs has polynomial complexity
791 kb

SIMULATION OF NONLINEAR COLOR OSCILLATIONS IN YANG-MILLS THEORY

abstract 1101506108 issue 110 pp. 1655 – 1674 30.06.2015 ru 747
The article presents the simulation of non-linear spatial-temporal color oscillations in Yang-Mills theory in the case of SU (2) and SU (3) symmetry. We examined three systems of equations derived from the Yang-Mills theory, which describes the transition to chaotic behaviour. These transitions are caused by nonlinear vibrations of colour, depending on the model parameters - the coupling constants and the initial wave amplitude. Such transitions to chaotic behaviour by increasing the parameters are characteristic of hydrodynamic turbulence. A model of spatial-temporal oscillations of the Yang-Mills theory in the case of three and eight colors. The results of numerical simulation show that the nonlinear interaction does not lead to a spatial mixing of colors as it might be in the case of turbulent diffusion. Depending on the system parameters there is a suppression of the amplitude of the oscillations the first three of five colors or vice versa - the first three five other colors. The kinetic energy fluctuations or shared equally between the color components, or dominated by the kinetic energy of repressed groups of colors. Note that the general property of physical systems described by nonlinear equations in the Yang-Mills theory and hydrodynamics is particularly strong in the formation of quark-gluon plasma and hadrons jets, when the Yang-Mills is involved in the formation of hydrodynamic flow. Note that there is a relationship between the Einstein and Yang-Mills theory, on the one hand, Einstein's equations and hydrodynamics - on the other. All of this points to the existence in the nature of a general mechanism of formation of a special type of turbulence - geometric turbulence
643 kb

SIMULATION OF PARTICLE DYNAMICS IN THE STERN-GERLACH APPARATUS

abstract 1171603060 issue 117 pp. 929 – 950 31.03.2016 ru 478
The model of the motion of particles in the SternGerlach apparatus in the classical and quantum mechanics was developed. The data simulation of particle trajectories and distribution of silver atoms on the surface of the plate in their deposition are discussed. It was found that for the experimentally observed distribution of two-dimensional shapes of the atoms must be assumed that the atoms are not involved in the precession motion in a magnetic field, while maintaining the direction of the magnetic moment, for example, parallel to the induction vector of the magnetic field during the time of motion in the apparatus. To obtain a realistic picture of the figure of the scattering of atoms used a classical model of movement and expression of forces compatible with the quantum picture of the motion of particles with spin ½. The magnetic field is simulated based on the original Stern-Gerlach data describing the distribution of the gradient of the induction components related to the splitting of the beam. Quantum model of particle motion is based on the Pauli equation in the boundary layer approximation. It is found that in this model, depending on the initial polarization of the particle, beam is split into either two or is deflected towards the magnet blade or in the opposite direction. It is shown that if the initial conditions for the task are reproducing the geometric dimensions and the magnetic field in the Stern-Gerlach apparatus, the figure of the scattering particles in the shape of the outline is similar to the experimentally observed shape
693 kb

SIMULATION OF PLASMOID AND STRAIMERS IN CONDUCTING ENVIRONMENT

abstract 1291705041 issue 129 pp. 471 – 497 31.05.2017 ru 493
In this work, a model is developed that describes the formation of a plasmoid and streamers in a conducting medium. To describe the contribution of the conductivity currents, we modified the standard electrostatic equation taking into account the vortex component of the electric field. As a result of this generalization, the streamer model is formulated in the form of a system of parabolictype nonlinear equations. As is known, in laboratories it is possible to create a plasmoid with a lifetime of 300- 500 ms and a diameter of 10-20 cm, which is interpreted as a ball lightning. With high-speed photography, a complex structure is detected, consisting of a plasmoid and surrounding streamers. Within the framework of the proposed model, problems are posed about the formation of a plasmoid and the propagation of streamers in an external electric field. In this model, the plasmoid is considered to be a long-lived streamer. The range of parameters in which a plasmoid of spherical shape is formed is indicated. It is established that there are three streamer branching mechanisms. The first mechanism is related to the instability of the front, which leads to the separation of the head of the streamer into two parts. The second mechanism is associated with the instability of the streamer in the base region, which leads to the branching of the streamer with the formation of a large number of lateral streamers closing the main channel of the streamer to the cathode. In numerical experiments, the third branching mechanism observed in experiments connected with the branching of the plasmoid in the cathode region with the closure of the space charge to the anode through the streamer system was observed. The similarity of ball lightning and plasmoid is discussed. If this similarity is confirmed, then the number of theoretical hypotheses concerning the nature of ball lightning, currently more than 200, can be drastically reduced to one described in this article
735 kb

SIMULATION OF TRANSFER OF BINARY ELECTROLYTE IN THE CHANNEL OF DESALTING OF ELECTRO DIALYSIS APPARATUS IN POTENTIAL STATIC MODE

abstract 0751201024 issue 75 pp. 309 – 322 27.01.2012 ru 1848
Article is devoted to the numerical analysis of regional problems for system of the equations of Nernst-Plank-Puasson (NPP), to application of these regional problems to modeling and studying of mass transfer in the channel desalting of electro dialysis device. Various mathematical models of the transfer of ions in potential static mode in the form of system of the quasilinear equations with private derivatives are offered. The basic rules of occurrence and development of a spatial charge in the channel desalting of electro dialysis device are revealed
604 kb

SIMULATION OF TURBULENT FLOW IN A CAVITY ON THE NAVIER-STOKES EQUATIONS

abstract 1191605079 issue 119 pp. 1111 – 1133 31.05.2016 ru 429
The article deals with the numerical solution of the Navier-Stokes equations describing turbulent flow in a rectangle cavity or in a cuboid with one open face at high Reynolds numbers. It is known, that there is a mechanism of turbulent mixing in natural systems, leading to an increase in the viscosity of the continuous medium. In this regard, we suggest methods of regularization of the Navier-Stokes equations, similar to the natural mechanisms of mixing. We proposed the models based on the properties of the turbulent environment. For this we modified the continuity equation taking into account the pressure fluctuations. It is shown that the incompressibility condition is can be violated due to pressure fluctuation even for flows with low Mach numbers. Modification of continuity equation by the introduction of turbulent viscosity allows the regularization of the Navier-Stokes equations to solve the problems with rapidly changing dynamic parameters. It was shown that the modification of the continuity equation taking into account turbulent fluctuations leads to a system of nonlinear equations of parabolic type. A numerical model of turbulent flow in the cavity with the rapid change in the parameters of the main flow developed. Discovered type of instability of the turbulent flow associated with the rapid changes in the main flow velocity. In numerical simulations found that due to the acceleration of the main flow there is the unsteady vortex flow in the cavity, which is characterized by the integral of energy not vanishing with time, vibrations that have a certain period, depending on the turbulent viscosity
835 kb

SIMULATION OF TURBULENT MHD FLOW IN A RECTANGULAR CAVITY IN A ROTATING MAGNETIC FIELD

abstract 1241610079 issue 124 pp. 1243 – 1268 30.12.2016 ru 562
The article deals with numerical solutions of MHD equations describing turbulent flow of a conducting fluid in a rectangular cavity in the rotating magnetic field at large values of the magnetic Taylor number, and Reynolds number. It is known that there is a mechanism of turbulent mixing in natural systems, leading to an increase in the viscosity of the continuous medium. In this regard, we suggest methods of regularization of the Navier-Stokes equations, similar to the natural mechanisms of mixing. The models based on the properties of currents of the turbulent environment proposed. A modification of the continuity equation taking into account the final magnitude of pressure fluctuations was considered. It is shown that due to pressure fluctuation the incompressibility condition can be violated even for flows with low Mach numbers. Modification of continuity in the system of NavierStokes equations by the introduction of turbulent viscosity allows the regularization of the NavierStokes equations to solve the problems with rapidly changing dynamic parameters, for example, in the case of a conducting fluid flow in a magnetic field rotating with a high frequency. It was shown that the modification of the continuity equation taking into account turbulent fluctuations leads to a system of nonlinear equations of parabolic type. A numerical model of turbulent MHD flow in a rectangular cavity with rapid change in flow parameters was proposed. In numerical calculations revealed that under the influence of a rotating magnetic field in a conducting fluid there are forces occur, causing unsteady vortex flow, which is consistent with experimental data. We have discovered a type of large scale instability of the turbulent flow, connecting with the secondary flow in a form of vortices
326 kb

SIMULATION OF TURBULENT TRANSPORT IN THE ATMOSPHERE PARTS 1, 2

abstract 0591005013 issue 59 pp. 179 – 218 31.05.2010 ru 2347
The completely closed model of wall turbulence was derived directly from the Navier-Stokes equation. The fundamental constants of wall turbulence including the Karman constant have been calculated within a theory. This model has been developed also for the accelerated and non-isothermal turbulent boundary layer flows over rough surface. Numerical solutions of equations system of turbulent transport of admixtures in a surface layer of the atmosphere for a large scale have been studied
220 kb

SOLUTION OF FIELD TASKS OF AN ELECTRICAL ENGINEERING WITH THE HELP OF SECONDARY SOURCES OF A FIELD AND FOURIER SERIES

abstract 0931309040 issue 93 pp. 591 – 603 30.11.2013 ru 1339
For a field task, we have shown the analytical solution of the control example by means of which the condi-tions of the correct application of a method of second-ary sources of a field. The numerical decision in the form of Fourier series of the same task, but with use of the method of secondary sources is found. The method of the registration of heterogeneity of the environment which enters secondary sources the way that bring together analytical and numerical solutions is offered
3033 kb

SOLVING PROBLEMS OF STATISTICS WITH THE METHODS OF INFORMATION THEORY

abstract 1061502001 issue 106 pp. 1 – 47 28.02.2015 ru 1008
The article presents a theoretical substantiation, methods of numerical calculations and software implementation of the decision of problems of statistics, in particular the study of statistical distributions, methods of information theory. On the basis of empirical data by calculation we have determined the number of observations used for the analysis of statistical distributions. The proposed method of calculating the amount of information is not based on assumptions about the independence of observations and the normal distribution, i.e., is non-parametric and ensures the correct modeling of nonlinear systems, and also allows comparable to process heterogeneous (measured in scales of different types) data numeric and non-numeric nature that are measured in different units. Thus, ASC-analysis and "Eidos" system is a modern innovation (ready for implementation) technology solving problems of statistical methods of information theory. This article can be used as a description of the laboratory work in the disciplines of: intelligent systems; knowledge engineering and intelligent systems; intelligent technologies and knowledge representation; knowledge representation in intelligent systems; foundations of intelligent systems; introduction to neuromaturation and methods neural networks; fundamentals of artificial intelligence; intelligent technologies in science and education; knowledge management; automated system-cognitive analysis and "Eidos" intelligent system which the author is developing currently, but also in other disciplines associated with the transformation of data into information, and its transformation into knowledge and application of this knowledge to solve problems of identification, forecasting, decision making and research of the simulated subject area (which is virtually all subjects in all fields of science)
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