Scientific Journal of KubSAU

Polythematic online scientific journal
of Kuban State Agrarian University
ISSN 1990-4665
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1374 kb

MATHEMATICAL MODEL OF ION TRANSPORT THROUGH THE INTERFACE: THE ION EXCHANGE MEMBRANE / STRONG ELECTROLYTE

abstract 1241610011 issue 124 pp. 210 – 242 30.12.2016 ru 973
The article presents a mathematical model of the ion transport across phase boundary exchange membrane / solution. The border is considered as an object in space, endowed with all the physical and chemical properties that are inherent physical and chemical phases. It is regarded as a special physical and chemical environment, having a distributed exchange capacity in which there is space charge dissociation of water molecules. The size of this object is estimated in the range of 1-300 nm. The surface morphology of industrial membrane type MK-40, МA-41 and МA-41P was investigated experimentally by scanning electron microscopy (REM). There was analyzed the amplitude of average surface roughness. In this article, the reaction layer is modeled as a region that forms as a relief morphology of the membrane. Membrane properties are due to the properties of the solution and the properties of the membrane. To determine the dependence of Q(x) is proposed procedure for assessing the proportion of solid phase in the total volume of which can be seen in the vertical cross section microprofile on the membrane surface line. Height multivendors determine the reaction layer zone on frame of model. Influence of surface morphology on the V-A characteristics and the sizes of the convective instability of cation-exchange membrane evaluated numerically simulating the hydrodynamic flow conditions using a solution of the Navier-Stokes equations. The transfer of a strong electrolyte such as NaCl ions through the thin layer of the reaction layer is considered. The place of nanomodel in the structure of a three-layer membrane system is showed. The distribution of the concentration of ions in the system, the charge density distribution and the dependence of the integrate charge with extent nanolayer is present. How to change the shape of the space charge and its integral value with one is investigated
266 kb

STATISTICAL MODELS IN MEDICINE

abstract 1241610063 issue 124 pp. 954 – 983 30.12.2016 ru 757
The article is devoted to the discussion of the organization of clinical-statistical studies and experiments. We have considered the examples of the application of statistical methods in scientific medical research. Under the clinical-statistical research we understand specially organized collection and analysis of medical data about the course of disease in patients, research of the dynamics of objective and subjective indicators of the state of reaction to these or other therapeutic effects. We study one, two or more groups of individuals (patients or healthy), conclusions are drawn on the whole group, but not for each individual patient. The purpose of research - to transfer the conclusions reached for the sample to the general population, i.e., clinical and statistical study focused on the production of useful recommendations concerning those patients who fall into the field of view of doctors after the end of the study. There are two main types of research - prospective and retrospective. The first related to the analysis of the last patients, the second - to monitoring the course of their disease in the future. We have considered typical mistakes in the organization of clinical-statistical studies. When planning a research, we usually distinguish the experimental and control groups, which are identical or similar in all respects except for the studied factors (exposure). We discuss the various options for blind methods and consider the application of statistical models and methods in scientific medical research. We have analyzed examples of confidence estimation of proportion (probability) and the homogeneity test of probabilities. For statistical modeling we use the Poisson distribution in the case of small probability. With its help, we analyze statistical data on the opisthorchiasis
255 kb

NUMBER OF CITATIONS AS A KEY PERFORMANCE INDICATOR OF SCIENTIFIC ACTIVITY OF RESEARCHERS AND ORGANIZATIONS

abstract 1241610064 issue 124 pp. 984 – 1009 30.12.2016 ru 688
We consider the methods for estimation of the effectiveness and quality of the scientific activities of the researcher, of the organization, of the magazine. Performance indicators of scientific activity are used as an important part in the estimation of higher education institutions, the innovative capacity of enterprises, etc. To estimate the effectiveness of scientific activity is natural to use intellectual tools which are well-established in other subject areas. This will include, in particular, the balanced scorecard, based on key performance indicators (hence the title of this article), as well as controlling, primarily controlling of research activities. There are two more developed and widely used types of tools for estimation the effectiveness of the scientific activity - the scientometric indicators and the expert estimators. Their critical analysis is the subject of this article. The goal - to choose the most effective tool. Different versions of manipulating of values of scientometric indicators in the Russian Federation, in our estimation, are still relatively rare. Perhaps this is due to the relatively short period of their use in the management of science. Since an indicator such as citation index (the number of citations of publications) of researcher, allows estimating its contribution to science, the use of this scientometric indicator for the management of science is justified. At the same time, the number of publications and especially h-index is not possible to objectively estimate the effectiveness of research activities, particularly in view of the properties of the real bibliometric databases. Expert procedures have several disadvantages. In this article we discuss the real effectiveness of expert procedures in the areas of their application, as conferring academic degrees and elections to the National Academy of Sciences (primarily in the Russian Academy of Sciences), as well as appointments to senior positions. The basic principles of expertise in these areas remain the same for the past 70 years. Based on an analysis of practice it is necessary to ascertain the lack of efficacy of expert estimators in these areas. Rationale to what has been said is given in the article
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 487
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
2310 kb

FUZZY MULTICLASS GENERALIZATION OF THE CLASSICAL F-MEASURE OF PLAUSIBILITY MODELS BY VAN RIJSBERGEN IN ASK-THE ANALYSIS AND THE SYSTEM OF "EIDOS"

abstract 1231609001 issue 123 pp. 1 – 29 30.11.2016 ru 647
Classic quantitative measure of the reliability of the models: F-measure by van Rijsbergen is based on counting the total number of correctly and incorrectly classified and not classified objects in the training sample. In multiclass classification systems, the facility can simultaneously apply to multiple classes. Accordingly, when the synthesis of the model description is used for formation of generalized images of many of the classes it belongs to. When using the model for classification, it is determined by the degree of similarity or divergence of the object with all classes, and a true-positive decision may be the membership of the object to several classes. The result of this classification may be that the object is not just rightly or wrongly relates or does not relate to different classes, both in the classical F-measure, but rightly or wrongly relates or does not relate to them in varying degrees. However, the classic F-measure does not count the fact that the object may in fact simultaneously belongs to multiple classes (multicrossover) and the fact that the classification result can be obtained with a different degree of similarity-differences of object classes (blurring). In the numerical example, the author states that with true-positive and true-negative decisions, the module similarities-differences of the object classes are much higher than for false-positive and false-negative decisions. It would therefore be rational to the extent that the reliability of the model to take into account not just the fact of true or false positive or negative decisions, but also to take into account the degree of confidence of the classifier in these decisions. In the intellectual system called "Eidos", which is a software toolkit for the automated system-cognitive analysis (ASC-analysis), we use initially proposed by its developers measure of the reliability of the models, which is essentially a fuzzy multiclass generalization of the classical F-measure (it is proposed to call it the L-measure). In this article, L-measure is mathematically described and its application is demonstrated on a simple numerical example
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 749
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
362 kb

THE INFLUENCE OF THE REACTION OF DISSOCIATION / RECOMBINATION OF MOLECULES OF WATER ON TRANSPORTATION OF ELECTROLYTE 1: 1 IN MEMBRANE SYSTEMS IN THE DIFFUSION LAYER. PART 3. EVALUATION OF THE POSSIBILITY OF THE EMERGENCE OF GRAVITATIONAL CONVECTION

abstract 1231609018 issue 123 pp. 283 – 297 30.11.2016 ru 551
This article is a continuation of the previous works of the authors [The influence of reaction dissociation / recombination of molecules of water on transportation of electrolyte 1:1 in the membrane systems in the diffusion layer. Part 1. Mathematical model // Scientific journal of Kuban State Agrarian University, 2016. No. 07(121) and The influence of the reaction of dissociation / recombination of molecules of water on transportation of electrolyte 1: 1 in membrane systems in the diffusion layer. Part 2. Asymptotic analysis // Scientific journal of Kuban State Agrarian University, 2016. – №08(122)] and devoted to assessing the possibility of gravitational convection due to the recombination of hydrogen and hydroxyl ions. The article presents the solution of a boundary-value problem, which is a mathematical model of electrodiffusion for the four types of ions at the same time (two ions of salts and hydrogen and hydroxyl ions) in the diffusion layer in electro-membrane systems with ideal selective membrane, with the heat transfer equation and the Navier-Stokes equation. The article shows the possibility of the emergence of gravitational convection due to the exothermic reaction of recombination of water molecules in the depth of the solution. The article considered the reaction of recombination of hydrogen ions and hydroxyl, although the main results can be applied, after appropriate modifications, and to amfolit-containing solutions, such as wine, juices, dairy products, microbiological processing of biomass (amino acids, anions of polybasic carboxylic acids), municipal effluent (anions of phosphoric acid), etc.
254 kb

THE ROLE OF QUANTUM ENTANGLEMENT IN TASKS OF THE GAMES THEORY

abstract 1231609019 issue 123 pp. 298 – 307 30.11.2016 ru 589
This article discusses an economic game called "The struggle for markets". We have generated a mathematical model of quantum realization of this game. For clarity, the algorithms are derived for soft and hard quantum games for assessing the impact of the degree of entanglement to work and the result of the algorithm. There are step-by-step instructions for the sequence of actions and operations to create a quantum model of the game. The aim is to assess the influence of the degree of entanglement on work algorithms. Also, we investigate the influence of quantum entanglement on the win for two or more players. The article gives a comparison with classical results
279 kb

ASYMPTOTICS OF QUANTIZATION, SELECTION OF THE NUMBER OF GRADATIONS IN THE SOCIOLOGICAL QUESTIONNAIRES AND TWO-LEVEL MODEL OF INVENTORY MANAGEMENT

abstract 1231609045 issue 123 pp. 660 – 687 30.11.2016 ru 484
We consider an approach to the transition from continuous to discrete scale which was defined by means of step of quantization (i.e. interval of grouping). Applied purpose is selecting the number of gradations in sociological questionnaires. In accordance with the methodology of the general stability theory, we offer to choose a step so that the errors, generated by the quantization, were of the same order as the errors inherent in the answers of respondents. At a finite length of interval of the measured value change of the scale this step of quantization uniquely determines the number of gradations. It turns out that for many issues gated it is enough to point 3 - 6 answers gradations (hints). On the basis of the probabilistic model we have proved three theorems of quantization. They are allowed to develop recommendations on the choice of the number of gradations in sociological questionnaires. The idea of "quantization" has applications not only in sociology. We have noted, that it can be used not only to select the number of gradations. So, there are two very interesting applications of the idea of "quantization" in inventory management theory - in the two-level model and in the classical Wilson model taking into account deviations from it (shows that "quantization" can use as a way to improve stability). For the two-level inventory management model we proved three theorems. We have abandoned the assumption of Poisson demand, which is rarely carried out in practice, and we give generally fairly simple formulas for finding the optimal values of the control parameters, simultaneously correcting the mistakes of predecessors. Once again we see the interpenetration of statistical methods that have arisen to analyze data from a variety of subject areas, in this case, from sociology and logistics. We have another proof that the statistical methods - single scientificpractical area that is inappropriate to share by areas of applications
202 kb

TESTING OF HOMOGENEITY OF PAIRED SAMPLES

abstract 1231609047 issue 123 pp. 708 – 726 30.11.2016 ru 488
The article begins with the letter of the chief engineer of chemical plant near Moscow. He requests to analyze of data by means of modern statistical methods and give an opinion on the presence (or absence) of the relationship between the two methods of determining the viscosity of the mastic. For each of the batches of mastic It was presented two numbers - the viscosity measurement results of the two methods. These numbers form two paired samples. We want to install, give whether two specific methods similar results. The true values of viscosity in different batches are not equal. Their difference is not allows us to combine the results of the first measurement method in first sample, the results of the second method - in the second sample, as we can do in the case of testing the homogeneity of two independent samples. For solutions to this problem we discuss four statistical criterions, based on a study of the differences between corresponding values in two paired samples. We test the hypothesis of equality 0 of median of these differences (sign test) and of equality 0 of the mathematical expectation of these differences. Hypothesis of testing of equality of the distribution functions of two paired samples is reduced to the hypothesis of symmetry of the distribution function of these differences with respect to 0. In the alternative of the shift is proposed to use the Wilcoxon signed rank criterion. In the total alternative is proposed to use criterion of the omega-square type which is developed by the author of this article
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