Scientific Journal of KubSAU

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

Kovalenko Anna Vladimirovna

Scholastic degree


Academic rank

Honorary rank

Organization, job position

Kuban State University
   

Web site url

Email

savanna-05@mail.ru


Articles count: 51

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143 kb

COMPARATIVE ANALYSIS OF METHODS OF ESTIMATION OF THE INCONSISTENCY OF AGRICULTURAL ENTERPRISES

abstract 0751201023 issue 75 pp. 294 – 308 27.01.2012 ru 1805
In the article, the analysis of inconsistency of agricultural enterprise is carried out by various methods. The hypothesis about absence of a universal method of an estimation of the inconsistency, yielding authentic result is proved
248 kb

ELECTRO-OSMOSIS IN MICRO - AND NANOCHANNELS. PART 1. AN OUTPUT OF A HIERARCHICAL SYSTEM OF MATHEMATICAL MODELS USING THE METHOD OF DECOMPOSITION

abstract 1141510028 issue 114 pp. 370 – 391 30.12.2015 ru 922
Micro and nanofluidics are the new multidisciplinary sciences. One of the tasks of which is creation and management of flow of fluid in the thin channels size of a few nano- or micrometer which exposed the external electric field, where the walls are the ion exchange membrane. Electroosmosis (electroconvection) plays an important role in these tasks. A large number of articless were devoted to electroosmosis. One of the first, Dukhin S.S., Mishchuk N.A. and Rubinstein I. gave a theoretical explanation of the overlimiting current by electroosmosis. They used two-dimensional Stokes equation to calculate the flow of the electrolyte, and one-dimensional equations of Nernst-Planck and Poisson to calculate the electric power. These researches have multiple limitations because of the computational complexity the mathematical simulation. Thus, there is an actual problem of the asymptotic solution of boundary value problems for the two-dimensional systems of equations of NernstPlanck and Poisson without these restrictions. These researches we derived in simplified models of electroosmosis in galvanic dynamical mode using the decomposition method. We have created a hierarchical system of two-dimensional mathematical models of ion transport of salt and electroosmosis in micro- and nanochannels formed by selective ion-exchange membranes
1356 kb

FINANCIAL RISK WARNING AT OIL PRODUCTION COMPANIES

abstract 1541910013 issue 154 pp. 132 – 154 30.12.2019 ru 218
This article is devoted to a problem of effective management of a financial and economic condition of companies on the example of the enterprises of oil products supply. We consider questions of support of adoption of management decisions which concern stabilization of a financial condition of the company and as a result of decrease in financial risks. The article also provides a description of the program complex called FESP_ON developed by the authors allowing to carry out the profound complex assessment of a financial and economic condition of Societies of oil products supply
901 kb

INVESTIGATION OF TRANSPORT OF SALT IONS IN THE EXPERIMENTAL ELECTROCHEMICAL CELL WITH ROTATING DISK MEMBRANE

abstract 0941310025 issue 94 pp. 335 – 346 27.12.2013 ru 1247
This work is a continuation of [1], which was devoted to the investigation of the hydrodynamics of the experimental electrochemical cell with rotating disk cation exchange membrane. This article focuses on the transport of salt ions in a closed cell at different initial experimentation with modes of exact current regimes. The main regularities of transport of salt ions and membrane equal accessible surface were set
360 kb

MANAGEMENT OF THE FINANCIAL AND THE ECONOMIC STATE OF A COMPANY USING A MATHEMATICAL MODEL

abstract 1231609017 issue 123 pp. 271 – 282 30.11.2016 ru 784
This article focuses on the mathematical modeling of evaluation of financial and economic activities of a company and on definition (based on this model) of such balance settings (line F1 and F2) which would make financial-economic indicators of the activities of the organization optimal, and the total cumulative score was the maximum. The knowledge and the use of the optimal parameters of the balance will allow the managers to plan strategy for the future development of the company. The article analyzes the dependencies of each of the 15 basic indicators (profitability, turnover, financial stability, liquidity and solvency) of financial and economic activity of the organization on the balance parameters. The optimal values of the parameters of the balance and the main indicators of financial and economic activities of the organization have been found. We have also built a mathematical model of optimal control of financial and economic indicators in the form of a problem of mathematical programming. For example, for the company called "Nika" it is shown the possibility of improving estimation of financial and economic condition of the organization. Knowledge of the optimal parameters of the balance will allow the managers to plan strategy for the future development of the organization. To solve this problem we have used the method of generalized reduced gradient implemented in Excel, with which there was found a maximum of the objective function for the article restrictions. The article describes the analysis algorithm of the optimization problem. A common assessment was carried out in stages, based on the calculation algorithm of sequentially improved target functions
301 kb

MATHEMATICAL MODELING FINANCIAL PERFORMANCE OF THE COMPANY WITH TAKING INO ACCOUNT ADVERTISING INVESTMENTS, AT THE EXAMPLE OF OIL-PRODUCT COMPANY

abstract 0641010007 issue 64 pp. 58 – 71 22.12.2010 ru 1981
The models of the estimation advertising effectiveness are reviewed and analyzed in the paper. The algorithm and example of the program’s work, which determines financial performance of the company with taking into account advertising investments is described and the mostly important results are discussed
1350 kb

MATHEMATICAL MODELING AND NUMERICAL STUDY OF THE HYDRODYNAMICS OF THE EXPERIMENTAL ELECTROCHEMICAL CELL WITH ROTATING DISK MEMBRANE

abstract 0941310024 issue 94 pp. 324 – 334 27.12.2013 ru 1285
This article investigates hydrodynamic of experimental electrochemical cell with rotating disk in the cation exchange membrane. We have also investigated the flow in open, with the free surface of the solution and in hermetically closed cells. The main regularities of the hydrodynamics of the experimental cell at its real size were set
1581 kb

MATHEMATICAL MODELING OF DESALTING OF GEOMETRIC ELECTRO CONVECTION HETEROGENEOUS SURFACE MEMBRANE IN ELECTRODIALYSIS APPARATUS

abstract 0721108018 issue 72 pp. 206 – 216 30.10.2011 ru 974
The article presents a mathematical model of the effect on ion transport electro convection salt in non-smooth camera channel desalting electro dialysis apparatus in the presence of forced convection. The basic rules of process of electro convection are revealed
834 kb

MATHEMATICAL MODELING OF ELECTROCONVECTION IN THE CAPILLARIES. TRANSIENT BEHAVIOR

abstract 1101506022 issue 110 pp. 340 – 350 30.06.2015 ru 1079
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
132 kb

MATHEMATICAL MODELING OF FINANCIAL PYRAMID SCHEME. PART 1. DEFINITIONS

abstract 0821208029 issue 82 pp. 378 – 388 31.10.2012 ru 2304
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
.