01.00.00 Physical-mathematical sciences
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METRIC OF ACCELERATING AND ROTATING REFERENCE SYSTEMS IN GENERAL RELATIVITY
01.00.00 Physical-mathematical sciences
DescriptionMetric describing the accelerated and rotating reference system in general relativity in the case of an arbitrary dependence of acceleration and angular velocity on time has been proposed. It is established that the curvature tensor in such metrics is zero, which corresponds to movement in the flat spaces. It is shown that the motion of test bodies in the metric accelerated and rotating reference system in general relativity is similarly to the classical motion in non-inertial reference frame. Consequently, there exist a metric in general relativity, in which the Coriolis theorem and classic velocity-addition formula are true. This means that classical mechanics is accurate rather than approximate model in general relativity. A theory of potential in non-inertial reference systems in general relativity is considered. The numerical model of wave propagation in non-inertial reference frames in the case when potential depending of one, two and three spatial dimensions has been developed. It is shown in numerical experiment that the acceleration of the reference system leads to retardation effects, as well as to a violation of the symmetry of the wave front, indicating that there is local change of wave speed
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A CLASSICAL PROBLEM FOR LOADED HYPERBOLIC-PARABOLIC EQUATION OF SECOND ORDER
01.00.00 Physical-mathematical sciences
DescriptionThe 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
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01.00.00 Physical-mathematical sciences
DescriptionRecently, the process of monetization of the evaluation of scientific activity was initiated, and there is a need for quantitative methods and comparable assessment of the effectiveness and quality of work of a scientist. There are numerous methods to reward for these results. What is common to all these techniques covered is the role of the Hirsch index or h-index. By itself, this index is well founded. However, in connection with the practice of application of h-index in our environment in the minds of the scientific community it has started some kind of mania, which the author proposes to call "Hirsch-mania". This mania is characterized by elevated unhealthy interest to the value of the Hirsch index, especially inadequate artificial exaggeration of this value, as well as a number of negative implications of this interest. In this article we have made an attempt to briefly describe some of the negative effects of this new mental infection that hit the public consciousness of the scientific community. And also we want to identify ways of overcoming at least some of their causes. This is the problem solved in this work. To solve the formulated problem, we propose to apply multi-criteria approach based on information theory, namely those options, which are implemented in an automated system-cognitive analysis (ASC-analysis) and its software tools - intelligent system called "Eidos
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01.00.00 Physical-mathematical sciences
DescriptionIn this article we consider a mathematical model of effect of non-compliance with the prevention of HIV/AIDS among a heterogeneous population based on known model by Kimbir et al (2006). The effectiveness of a condom use and implications of non-compliance with a population of preventive measures (condoms) are the aim of this research work. In this work, with definite coefficients, nonlinear model is used, which consists of system of six differential equations for different population groups (six groups of the population) to obtain the model equations. Compared with the existing model by Kimbir, the proposed model to a large extent, takes into account the birth rate of the studied population. Numerical simulation of the model equations shows that reducing the rate of transmission of HIV/AIDS can be effectively achieved within a certain time, and only where relatively high condom efficacy and high compliance by susceptible and infected are observed. From the obtained results, we can see that the control of HIV/AIDS in the heterosexual population depends on the net compliance and effectiveness of the recommended prevention (condom use). As a recommendation, the model focuses on intensive training and ongoing campaigns to raise the awareness of the population by governmental and non-governmental agencies on the effective use of the condom
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ON SOME APPROACHES TO ECONOMICMATHEMATICAL MODELING OF SMALL BUSINESS
01.00.00 Physical-mathematical sciences
DescriptionSmall business is an important part of modern Russian economy. We give a wide panorama developed by us of possible approaches to the construction of economic-mathematical models that may be useful to describe the dynamics of small businesses, as well as management. As for the description of certain problems of small business can use a variety of types of economic-mathematical and econometric models, we found it useful to consider a fairly wide range of such models, which resulted in quite a short description of the specific models. In this description of the models brought to such a level that an experienced professional in the field of economic-mathematical modeling could, if necessary, to develop their own specific model to the stage of design formulas and numerical results. Particular attention is paid to the use of statistical methods of non-numeric data, the most pressing at the moment. Are considered the problems of economic-mathematical modeling in solving problems of small business marketing. We have accumulated some experience in application of the methodology of economic-mathematical modeling in solving practical problems in small business marketing, in particular in the field of consumer goods and industrial purposes, educational services, as well as in the analysis and modeling of inflation, taxation and others. In marketing models of decision making theory we apply rankings and ratings. Is considered the problem of comparing averages. We present some models of the life cycle of small businesses - flow model projects, model of capture niches, and model of niche selection. We discuss the development of research on economic-mathematical modeling of small businesses
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LIMIT THEOREMS FOR KERNEL DENSITY ESTIMATORS IN SPACES OF ARBITRARY NATURE
01.00.00 Physical-mathematical sciences
DescriptionSome estimators of the probability density function in spaces of arbitrary nature are used for various tasks in statistics of non-numerical data. Systematic exposition of the theory of such estimators had a start in our work [2]. This article is a direct continuation of the article [2]. We will regularly use references to conditions and theorems of the article [2], in which we introduced several types of nonparametric estimators of the probability density. We studied more linear estimators. In this article we consider particular cases - kernel density estimates in spaces of arbitrary nature. When estimating the density of the one-dimensional random variable, kernel estimators become the Parzen-Rosenblatt estimators. Asymptotic behavior of kernel density estimators in the general case of an arbitrary nature spaces are devoted to Theorem 1 - 8. Under different conditions we prove the consistency and asymptotic normality of kernel density estimators. We have studied uniform convergence. We have introduced the concept of "preferred rate differences" and studied nuclear density estimators based on it. We have also introduced and studied natural affinity measures which are used in the analysis of the asymptotic behavior of kernel density estimators. We have found the asymptotic behavior of dispersions of kernel density estimators and considered the examples including kernel density estimators in finite-dimensional spaces and in the space of square-integrable functions
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01.00.00 Physical-mathematical sciences
DescriptionIn this article we propose a method that uses the apparatus of the theory of fuzzy sets, together with the five-factor model of Altman in assessing the creditworthiness of an enterprise. Altman's model works in two ways: It applies the root mean square (RMS) integral approximation for the exact calculation of quantitative assessment of creditworthiness (probability of bankruptcy), and using the device of fuzzy sets for ordered sets by the degree of confidence in the resulting probability. In this paper we conducted simulation procedure for the credit assessment and showed the capabilities of the model. The model input parameters , forms system inputs (input variables), allowing you to get the value of the parameter z of Altman. With the help of Altman's model, approximating function L6, the decision function I(p) and the algorithm for calculating preference we obtain the number of the set i to which belongs a number of ordered sets as fuzzy logic . On the selected simulation parameters, stable statistics can be obtained. Altman's model with the use of computational function allows real values of the input parameters of the enterprise replaced by random values of the simulation model. This technique allows, as shown by the results of computational experiments, the creditor to obtain additional information on the creditworthiness of the investigated enterprise and make a more informed conclusion about its financial condition, which speeds up the decision on the possibility of issuing the required credit. The development of method of estimating fuzzy logic can be applied to other models of assessing the creditworthiness of a company: Davydov's model, Zaitseva's, Saifullina's, Kadykova's and others with appropriate modification
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01.00.00 Physical-mathematical sciences
DescriptionMetric describing the accelerated and rotating reference system in general relativity in the case of an arbitrary dependence of acceleration and angular velocity on time has been proposed. It is established that the curvature tensor in such metrics is zero, which corresponds to movement in the flat spaces. It is shown that the motion of test bodies in the metric accelerated and rotating reference system in general relativity is similarly to the classical motion in non-inertial reference frame. Maxwell's equations and Yang-Mills theory are converted to the moving axes in metric describes the acceleration and rotating reference frame in the general relativity in the case of an arbitrary dependence of acceleration and angular velocity of the system from time. The article discusses the known effects associated with acceleration and (or) the rotation of the reference frame - the Sagnac effect, the effect of the Stewart-Tolman and other similar effects. The numerical model of wave propagation in non-inertial reference frames in the case when potential depending of one, two and three spatial dimensions has been developed. It has been shown in numerical experiment that the acceleration of the reference system leads to retardation effects, as well as to a violation of the symmetry of the wave front, indicating that there is local change of wave speed
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01.00.00 Physical-mathematical sciences
DescriptionIn the article we consider integrative codes of the elements of discrete systems for the first time. It is shown that these codes in the general case divided into group and system parts. The group part of the code characterizes a set of elements with identical value of the sign as a whole. System part of the code appears when different sets are combined into the system. We have established that in using the weighted average of these parts of integrative code we can express information measures of combinatorial, probabilistic and synergistic approaches to determine the quantity of information. It is concluded that there is an integrative coding relationship between these approaches, and the existing types of information have genetic relationship. It is shown that the information considered in the synergetic approach is genetically of primary in relation to the information, which operates on the combinatorial and probabilistic approaches. Also, we have answered the question why the different conceptions of information lead to identical formulas to measure it
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01.00.00 Physical-mathematical sciences
DescriptionThe quality of a system is seen as an emergent property of systems, due to their composition and structure, and it reflects their functionality, reliability and cost. Therefore, when we speak about quality management, the purpose of management is the formation of pre-defined system properties of the object of management. The stronger the object of the control expresses its system properties, the stronger the nonlinearity manifests of the object: both the dependence of the management factors from each other, and the dependence of the results of the action of some factors from the actions of others. Therefore, the problem of quality management is that in the management process the management object itself changes qualitatively, i.e. it changes its level of consistency, the degree of determinism and the transfer function itself. This problem can be viewed as several tasks: First is the system identification of the condition of the object of management, 2nd – making decisions about controlling influence that changes the composition of the control object in a way its quality maximally increases at minimum costs. To solve the 2nd problem we have proposed an application of the component selection of the object by functions based on the resources allocated for the implementation of different functions; costs associated with the choice of the components and the degree of compliance of various components to their functional purpose. In fact, we have proposed a formulation and a solution of the new generalization of a variant of the assignment problem: "multi backpack", which differs from the known with the fact that the selection has been based not only on the resources and costs, but also with taking into account the degree of compliance of the components to their functional purpose. A mathematical model, which provides a solution to the 1st problem, and reflecting the degree of compliance of the components to their functionality, as well as the entire decision-making process for selections, i.e. 2nd task, has been implemented in the ASC-analysis and in the system called "Eidos" X++". The article also provides a simplified numerical example of the proposed approach with the selection of staff members