Scientific Journal of KubSAU

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

A CLASSICAL PROBLEM FOR LOADED HYPERBOLIC-PARABOLIC EQUATION OF SECOND ORDER

abstract 1071503113 issue 107 pp. 1745 – 1756 31.03.2015 ru 939
The investigated and correct boundary value problem for mixed hyperbolic-parabolic equation of second order in a bounded domain is posed and studied in this work. Boundary conditions are of a classical nature. On line of type changes, which is also the line of the parabolic degeneracy for hyperbolic equations considered in the lower half-plane, a continuous bonding condition for the function itself and the breaking condition for the trace of the derivative is given. The main result is the proof of its unique solvability in the required class of functions. In particular, based on the properties of the operators of fractional integro-differentiation and in view of the ratio of the first boundary value problem for the heat equation, the question of the solvability of the original problem was equivalently reduced to the problem of solvability of the corresponding integral equation of the Voltaire second kind. In the hyperbolic part of the region, the question of solvability of the problem has also been reduced to the problem of solvability of the integral equation Voltaire second kind. The properties of the hypergeometric function of Gauss, as well as classical methods of integral equations were used. Thus it is proved the uniqueness and the existence of classical solution to the initial problem
3033 kb

SOLVING PROBLEMS OF STATISTICS WITH THE METHODS OF INFORMATION THEORY

abstract 1061502001 issue 106 pp. 1 – 47 28.02.2015 ru 1001
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)
175 kb

PROBABILISTIC-STATISTICAL MODELING THE INTERFERENCES FROM ELECTRIC LOCOMOTIVES

abstract 1061502016 issue 106 pp. 225 – 238 28.02.2015 ru 808
The movements of electric locomotives create the interferences affecting the wired link. The creation of sufficiently technical effective and at the same time cost-effective means of protection from wireline interferences generated traction networks assumes as a preparatory phase to develop mathematical models of interference caused by electric locomotives. We have developed a probabilistic-statistical model of interferences caused by electric locomotives. The asymptotic distribution of the total interference is the distribution of the length of the two-dimensional random vector whose coordinates - independent normally distributed random variables with mean 0 and variance 1. Limit theorem is proved for the expectation of the total amplitude of the interferences. Monte-Carlo method is used to study the rate of convergence of the expectation of the total amplitude of the interferences to the limiting value. We used an algorithm of mixing developed by MacLaren-Marsaglia (M-algorithm). Five sets of amplitudes are analyzed, selected in accordance with the recommendations of experts in the field of traction AC networks. The most rapid convergence to the limit takes place in the case of equal amplitudes. It was found that the maximum possible average value of the amplitude of the random noise by 7.4% less than the previously used value, which promises a significant economic impact
285 kb

CURRENT STATUS OF NONPARAMETRIC STATISTICS

abstract 1061502017 issue 106 pp. 239 – 269 28.02.2015 ru 1516
Nonparametric statistics is one of the five points of growth of applied mathematical statistics. Despite the large number of publications on specific issues of nonparametric statistics, the internal structure of this research direction has remained undeveloped. The purpose of this article is to consider its division into regions based on the existing practice of scientific activity determination of nonparametric statistics and classify investigations on nonparametric statistical methods. Nonparametric statistics allows to make statistical inference, in particular, to estimate the characteristics of the distribution and testing statistical hypotheses without, as a rule, weakly proven assumptions about the distribution function of samples included in a particular parametric family. For example, the widespread belief that the statistical data are often have the normal distribution. Meanwhile, analysis of results of observations, in particular, measurement errors, always leads to the same conclusion - in most cases the actual distribution significantly different from normal. Uncritical use of the hypothesis of normality often leads to significant errors, in areas such as rejection of outlying observation results (emissions), the statistical quality control, and in other cases. Therefore, it is advisable to use nonparametric methods, in which the distribution functions of the results of observations are imposed only weak requirements. It is usually assumed only their continuity. On the basis of generalization of numerous studies it can be stated that to date, using nonparametric methods can solve almost the same number of tasks that previously used parametric methods. Certain statements in the literature are incorrect that nonparametric methods have less power, or require larger sample sizes than parametric methods. Note that in the nonparametric statistics, as in mathematical statistics in general, there remain a number of unresolved problems
278 kb

OPTIMAL PLAN OF INVENTORY CONTROL CANNOT BE FOUND BASED ON THE FORMULA OF THE SQUARE ROOT

abstract 1061502018 issue 106 pp. 270 – 300 28.02.2015 ru 973
Inventory management (in other words, logistics) is an integral part of the work of firms, companies and organizations. We are talking about stocks of raw materials, fuel, tools, components, semi-finished products, finished products for industrial (or agricultural) firms, about stocks of goods to distribution centers, warehouses, shops, workplaces sellers, finally consumers. Stocks spent all the time and supplemented on various rules adopted in the firm. Optimization of these rules, ie, optimal inventory management, gives a big economic effect. The mathematical theory of inventory management, based on the models of movement of flows of goods, is an important area of economic-mathematical research. The classical model of inventory management proposed in 1915 by F. Harris is one of the simplest and most illustrative examples of application of the mathematical apparatus for decision-making in the economic field. This model is commonly referred to as the Wilson model, because this model became known after the publication of R.G. Wilson in 1934. The formula of the optimum batch size (the so-called "the formula of the square root"), obtained in the Wilson model, is widely used on various stages of production and distribution, since this formula is practically useful for decision-making in the inventory management, in particular, for generating significant economic effect. However, contrary to popular belief, by means of this formula it is impossible to calculate the optimal batch size (although it is a necessary step on the path of its finding). In strict economic-mathematical analysis of Wilson model, conducted in the article, it is shown that the formula of square root does not give the optimal batch size. We have given the algorithm for calculating the optimal batch size. It has been found that the formula of the square root gives asymptotically optimal plan. We have studied the stability of the conclusions in the economic-mathematical model and considered an example of the practical application of the classical model of inventory management
231 kb

HIGH STATISTICAL TECHNOLOGIES

abstract 1051501002 issue 105 pp. 14 – 38 30.01.2015 ru 1002
In practical use of methods of applied statistics we do not apply separate methods for describing data, estimation, testing hypotheses, but we must use deployed whole procedures - the so-called "statistical technology". The concept of "statistical technology" is similar to the concept of "technological process" in the theory and practice of organization of production. It is quite natural that some statistical technology can better meet the needs of the researcher (user, statistics) than others, some - are modern, and others - outdated, some properties are studied, and the others - no. It is important to stress that a qualified and efficient use of statistical methods - this is not one single statistical hypothesis testing and estimation of characteristics or parameters of a given distribution from fixed family. This kind of operations - only the individual building blocks that make up the statistical technology. The procedure of the statistical data analysis - is an information process, in other words, one or other information technology. Statistical information is subject to a variety of operations (series, parallel, or more complex schemes). In this article we discuss statistical technologies and the problem of "docking" algorithms. We introduce the concept of "high statistical technologies" and then we prove the necessity of their development and application. As the examples we have given the researches of Institute of high statistical technologies and econometrics of Bauman Moscow State Technical University. We have also considered a number of education problems in domain of high statistical technologies
267 kb

PROBABILITY MODELS FOR OBTAINING NON-NUMERICAL DATA

abstract 1051501003 issue 105 pp. 39 – 66 30.01.2015 ru 1000
The statistics of objects of non-numerical nature (statistics of non-numerical objects, non-numerical data statistics, non-numeric statistics) is the area of mathematical statistics, devoted to the analysis methods of non-numeric data. Basis of applying the results of mathematical statistics are probabilistic-statistical models of real phenomena and processes, the most important (and often only) which are models for obtaining data. The simplest example of a model for obtaining data is the model of the sample as a set of independent identically distributed random variables. In this article we have considered the basic probabilistic models for obtaining non-numeric data. Namely, the models of dichotomous data, results of paired comparisons, binary relations, ranks, the objects of general nature. We have discussed the various options of probabilistic models and their practical use. For example, the basic probabilistic model of dichotomous data - Bernoulli vector (Lucian) i.e. final sequence of independent Bernoulli trials, for which the probabilities of success may be different. The mathematical tools of solutions of various statistical problems associated with the Bernoulli vectors are useful for the analysis of random tolerances; random sets with independent elements; in processing the results of independent pairwise comparisons; statistical methods for analyzing the accuracy and stability of technological processes; in the analysis and synthesis of statistical quality control plans (for dichotomous characteristics); the processing of marketing and sociological questionnaires (with closed questions like "yes" - "no"); the processing of socio-psychological and medical data, in particular, the responses to psychological tests such as MMPI (used in particular in the problems of human resource management), and analysis of topographic maps (used for the analysis and prediction of the affected areas for technological disasters, distributing corrosion, propagation environmentally harmful pollutants, various diseases (including myocardial infarction), in other situations), etc.
2215 kb

PREDICTING GLOBAL CLIMATIC ANOMALIES SUCH AS EL NINO AND LA NINA BY USING ASC-ANALYSIS WITH AIDOS-X ARTIFICIAL INTELLIGENCE SYSTEM

abstract 1051501007 issue 105 pp. 128 – 160 30.01.2015 ru 870
A number of information and semantic models has been developed using artificial intelligence system AIDOS-X. The similarity between the movement of the elements of the lunar orbit and the dynamics of the instantaneous pole of the Earth, as well as violations of the global atmospheric circulation and water, leading to the emergence of episodes of El Niño and La Niña are justified. We have explored a possibility of semantic information models equatorial regions of the Pacific for prediction of global climatic disturbances in the tropical latitudes. We made a forecast about breaking of global ocean circulation, or the occurrence of El Niño episode of the classical type in 2015
426 kb

RIEMANNIAN GEOMETRY AND UNIFIED FIELD THEORY IN 6D

abstract 1051501008 issue 105 pp. 161 – 186 30.01.2015 ru 1052
The article discusses the Riemann's unified field theory and its extension in 6D in general relativity. It is shown that in 6D there are possible movements on two spherical areas in the form of nonlinear waves
151 kb

BEAVER’S TECHNIQUE OF RISK ASSESSMENT IN THE ESTIMATION OF THE FINANCIAL POSITIONS OF COMPANIES USING MATHEMATICAL OPTIMIZATION

abstract 1051501023 issue 105 pp. 425 – 434 30.01.2015 ru 1022
In this article we propose a method of determining the share or the significance (weight) of indicators of Beaver and risks R in the portfolio formed by these parameters allowing us to minimize the mean square error evaluating the effectiveness of the portfolio (risk) in the assessment of the financial condition of the companies investigated. The proposed method is the minimization of a quadratic form in variables satisfying lengthy conditions, i.e. the quadratic programming. This technique is implemented using four methods of optimization: analytical method, using built-in function minimization block given, the penalty function method and the gradient method. More so, this technique allows, as shown by the results of the computational experiments, the expert without routine statistical data processing to obtain additional information on the credit worthiness of the investigated enterprise and make a more informed conclusion about its financial condition, which speeds up the decision on granting a loan required by a company. Based on the techniques proposed in this paper, other techniques of assessing the creditworthiness of businesses may be constructed using the results of optimization theory based on well-established applied research methods: Method of evaluating the creditworthiness of Russia, Credit scoring method, the American method, method of Altman and others
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