Scientific Journal of KubSAU

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

MATHEMATICAL MODELING OF ELECTROCONVECTION IN THE CAPILLARIES. TRANSIENT BEHAVIOR

abstract 1101506022 issue 110 pp. 340 – 350 30.06.2015 ru 1097
We propose a mathematical model of ion transport binary salt in electroosmotic flow in a capillary. The capillary is open on one side and immersed in a vessel of large volume, in which the concentration of the solution is maintained constant, and the other side closed ion exchange membrane. The walls are considered wettable, i.e. the solution adheres to the walls. This means that the mathematical modeling used to rate the condition of sticking. We study the boundary value problem for a coupled system of equations Nernst, Planck, Poisson and Navier-Stokes equations. Used boundary conditions of general form. The mathematical model is based on the general laws of transport and contains no adjustable parameters. Using this model, the basic laws of ion transport salt solution liquid flow, the emergence and development electroconvection, distribution of concentration of salt ions in the capillary with a small change in time, ie, in the initial (transitional) regime. We have identified the presence of ion-exchange membrane surface electroconvective vortices and their influence on the mechanisms of ion transport of salt and fluid movement in different areas of the capillary. A feature of the capillary transport is to the right of the vortex region stagnant areas with a higher concentration of ions
523 kb

MATHEMATICAL MODELING OF EPIZOOTIC SITUATION IN A RADIOACTIVE CONTAMINATED AREA – EVIDENCE FROM BOVINE LEUCOSIS IN CHELYABINSK REGION

abstract 0751201047 issue 75 pp. 585 – 594 27.01.2012 ru 1319
Simulation models are designed to reflect the cause-effect relationships between epizootic situation tensity for bovine leucosis and technogenic & radiation factors of environmental pollution. Zoning of Chelyabinsk region in terms of epizootic risk of bovine leucosis was carried out
132 kb

MATHEMATICAL MODELING OF FINANCIAL PYRAMID SCHEME. PART 1. DEFINITIONS

abstract 0821208029 issue 82 pp. 378 – 388 31.10.2012 ru 2313
The article analyzes the various approaches to the mathematical modeling of financial pyramids. It considered “economically rational subject”, game approach and the approach of Dubovsky. In this article, the mathematical models of the unproblematic approaches examined; we also analyzed their characteristics, including the dependence of the lifetime of the pyramid of accrued interest and the number of clients, the maximum possible profit of the founders of the pyramid, etc. This work analyzes the various options of the campaign, including whether the implicit advertising company, which arises from the spread of the financial company clients and rumors about their income
127 kb

MATHEMATICAL MODELING OF FINANCIAL PYRAMID SCHEME. PART 2. CONTINUOUS MODELS

abstract 0821208031 issue 82 pp. 402 – 412 31.10.2012 ru 1379
This article is devoted to the analysis of different cases of changing the number of customers of the financial pyramid and the establishment of the basic rules of the pyramid schemes on the basis of continuous models, and it is a continuation of works [1, 2], which had formulas to simulate the amount collected by the pyramid scheme and it considers the discrete models
140 kb

MATHEMATICAL MODELING OF FINANCIAL PYRAMID SCHEME. PART 2. DISCRETE MODELS

abstract 0821208030 issue 82 pp. 389 – 401 31.10.2012 ru 1764
This article analyzes the changes in the number of cases of various clients of the pyramid and the establishment of the basic rules of the pyramid schemes based on discrete models. The article is also a continuation of previous work [1], which had formulas to simulate the amount collected by the pyramid scheme
237 kb

MATHEMATICAL MODELING OF HIGH VOLTAGE INDUCTION MOTORS FOR AGRICULTURAL ELECTRICAL POWER SUPPLY SYSTEMS

abstract 1101506036 issue 110 pp. 532 – 542 30.06.2015 ru 1124
This article is devoted to solving the critical task of improving the reliability of the power systems for agricultural processing plants. The article’s material is exploratory in nature, reflected in the fact that the proposed mathematical models for the analysis of groups of high-voltage induction motors will allow to investigate various modes of symmetric groups of asynchronous motors more effectively. We present the analysis of the existing mathematical models of induction motors considering the design features of such machines that directly affect the dependence of resistance and inductance on the rotor current frequency. The assumptions taken into consideration to obtain a more accurate mathematical model of the induction motor are also formulated. The article provides a comparison of different reference frames used in the mathematical modeling of asynchronous motors. It is proved that the use of the generalized coordinate vector for mathematical modeling of asynchronous motors is the most optimal approach. The equivalent circuit of asynchronous deep-bar motor in generalized vector coordinates derived in the work is used for analysis of transient behavior as well as the steady state operation. The results of the study are suitable for transient analysis of electrical power supply systems of agricultural enterprises with large number of high-power electric motors, for example, CHP of sugar processing plants and grain elevators
495 kb

MATHEMATICAL MODELING OF INFLUENCE SURFACE MORPHOLOGY OF HETEROGENEOUS ION-EXCHANGE MEMBRANE TO THE ELECTROCONVECTION

abstract 1041410098 issue 104 pp. 1316 – 1327 30.12.2014 ru 1300
This article is a continuation of [1] devoted to the definition of a system of indicators to assess the creditworthiness of Russian regions, obtaining the minimum and the optimal number of clusters for the regions dependent credit index, the construction ofdiscriminant models to assess the creditworthiness of the regions, with the reliability of recognition of 91% and 96%. However, adequate and effective assessment of the state of the region, the model of multivariate statistical analysis is necessary to supplement and use them in conjunction with other models of assessment of the region, such as fuzzy are the production, hybrid systems, neural networks, i.e., create a representative group of methods. Development of fuzzy and fuzzy hybrid (neuro-fuzzy) systems for the credit assessment of regions subject of this article
541 kb

MATHEMATICAL MODELING OF INTERACTION OF LEVER BREAKER WITH STUMB AND SOIL

abstract 0771203028 issue 77 pp. 290 – 301 30.03.2012 ru 1768
Analytical dependence, defining powers and moments influencing the working unit of lever breaker are shown, which allow determining the stubbing force necessary in adjustment for requirements for modes and parameters of work of lever breaker
284 kb

MATHEMATICAL MODELING OF ION TRANSPORT THROUGH MEMBRANES IN THE CONDITION OF PREVIOUS SLOW HOMOGENEOUS CHEMICAL REACTION. MATHEMATICAL PROBLEM

abstract 1251701003 issue 125 pp. 85 – 101 31.01.2017 ru 737
In the article we build a mathematical model of elec-tro-diffusion of ions in the diffusion layer of a mem-brane system complicated by the occurrence of the previous slow homogeneous chemical reaction with the condition of electrical neutrality of the solution. We have set a two-point boundary value problem and developed a method to solve it; we have given an algorithm and a numerical method for solving it in Comsol 3.5 environment. The formula for limiting kinetic current was derived. Some of the model’s capabilities to describe the properties of the system are given
304 kb

MATHEMATICAL MODELING OF MTU TENSILE LOAD

abstract 1001406015 issue 100 pp. 289 – 302 30.06.2014 ru 1378
The article is devoted to mathematical modeling of random process that occurred in tensile load of serial and experienced MTU. The efficiency of EDM application in transmission is discussed
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