01.00.00 Physical-mathematical sciences
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ECONOMETRICS AS AN ACADEMIC DISCIPLINE
01.00.00 Physical-mathematical sciences
DescriptionStatistical methods are widely used in domestic feasibility studies. However, for most managers, economists and engineers, they are exotic. This is due to the fact that modern statistical methods are not taught in the universities. We discuss the situation, focusing on the statistical methods for economic and feasibility studies, ie, econometrics. In the world of science, econometrics has a rightful place. There are scientific journals in econometrics, Nobel Prizes in Economics are given to series of researches in econometrics. The situation in the field of scientific and practical work and especially the teaching of econometrics in Russia is disadvantaged. Often, individual particular constructions replace econometrics in general, such as those related to regression analysis. The article is devoted to econometrics as an academic discipline. Our course begins with a discussion of the structure of modern econometrics, the connections between applied statistics and econometric methods. We consider sample researches (analysis of surveys results), the elements of econometrics numbers, and methods of testing of statistical hypothesis about homogeneity. We have given the concepts of regression analysis, econometric classification methods, modern measurement theory. The important places are occupied by the statistics of non-numerical data (including fuzzy sets and their links with random sets) and the statistics of interval data. The problem of the stability of statistical procedures with respect to the tolerances of input data and model prerequisites is discussed. The representations of the econometric methods of expert research and quality control, analysis and forecasting of time series, econometrics of forecasting and risks are given
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PROPAGATION AND BRANCHING OF STRAIMERS IN CONDUCTING ENVIRONMENT
01.00.00 Physical-mathematical sciences
DescriptionIn this work, we develop a model describing the propagation and branching of a streamer in a conducting medium in external electric field. To describe the contribution of the conductivity currents, we modified the standard electrostatic equation taking into account the vortex component of the electric field. As a result of this generalization, the streamer model is formulated in the form of nonlinear equations of parabolic type. In the framework of the proposed model, the problem of the propagation of a streamer in the form of a traveling wave is considered, which leads to the emergence of SaffmanTaylor streamers. For streamers of this type, the branching problem is formulated, which has a unique solution. The dependence of the branch point on the parameters of the problem-the speed of the streamer, the diffusion coefficient of the electrons and the strength of the external electric field, is found. The branching mechanism of the streamer head by dividing it into two parts has been well studied and several alternative models have been formulated for its description. The novelty of the problem in question is that the streamer splits into two three-dimensional channels that are symmetric with respect to the given plane. Numerical experiments also revealed the mechanism of branching of the streamer in the cathode region, connected with the separation of the main channel into several lateral branches. It is noted, that in nature both branching mechanisms are realized, whereas in theory the instability of the surface of the streamer head is investigated
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THE NUMBER OF LINEARLY ORDERABLE BINARY RELATIONS ON A FINITE SET
01.00.00 Physical-mathematical sciences
DescriptionPartially ordered set is a basic concept of modern settheoretic mathematics. The problem of linear set ordering with given binary relations is well-known. Every partial order over a finite set can be linearly ordered, but not every binary relation over this set can be linearly ordered as well. Up to now, there is no known formula for calculating the number of partial orders over a given finite set. It appears that there is a formula for calculating linearly ordered binary relations over a finite set. This article is concerned with derivation of this formula. The fact from work of G.N. Titov [9] that a binary relation over a finite set is linearly ordered if and only if any diagonal block, derived from the binary relation matrix as a result of setting main diagonal elements to zero, contains at least one zero row (diagonal block of matrix means any matrix composed of elements at the crossings of rows and columns of a given matrix with the same numbers), plays a key role in process of corroboration. The main conclusion of the article is a theorem that allows to find the number of linearly ordered binary relations over a set of n elements using the formula. A recurrence formula for the number of linearly ordered (irreflexive) binary relations over a finite set of n elements, provided in the lemma, was derived as well
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01.00.00 Physical-mathematical sciences
DescriptionIn this article, we have proposed a forecast of labor resources by sectors of the labor market of the Russian Federation until 2018 inclusive. The probabilistic parameters of the dynamics of labor resources were calculated using the considered model (articles [1-4]). Further, these probabilities were used to estimate and parameterize the trends of employed and unemployed (with a known last place of employment) specialists in each industry. For each sector of the Russian economy, the type of trend that best approximates the long-term (more than three years) dynamics of labor resources in this sector was selected. It is shown that the forecast error for 1 year is less than 1% using the selected trend models. Further, identified long-term trends were used in forecasting. Based on the results of the forecast of the number of people employed in the sectors of the Russian economy, the sectors were divided into two groups. The first group contains sectors with a significant change in the number of employed in. The second group contains sectors, changes in employed in which were insignificant. At the end of the article, an example of an analysis of two sectors from the first group is given. Causes of changes in the dynamics of labor resources in the researched sectors of the economy were identified. Ones of the main sectors of the economy were considered in this example: "Manufacturing industries" and "Financial activities, real estate transactions, leasing and provision of services"
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SIMULATION OF PLASMOID AND STRAIMERS IN CONDUCTING ENVIRONMENT
01.00.00 Physical-mathematical sciences
DescriptionIn this work, a model is developed that describes the formation of a plasmoid and streamers in a conducting medium. To describe the contribution of the conductivity currents, we modified the standard electrostatic equation taking into account the vortex component of the electric field. As a result of this generalization, the streamer model is formulated in the form of a system of parabolictype nonlinear equations. As is known, in laboratories it is possible to create a plasmoid with a lifetime of 300- 500 ms and a diameter of 10-20 cm, which is interpreted as a ball lightning. With high-speed photography, a complex structure is detected, consisting of a plasmoid and surrounding streamers. Within the framework of the proposed model, problems are posed about the formation of a plasmoid and the propagation of streamers in an external electric field. In this model, the plasmoid is considered to be a long-lived streamer. The range of parameters in which a plasmoid of spherical shape is formed is indicated. It is established that there are three streamer branching mechanisms. The first mechanism is related to the instability of the front, which leads to the separation of the head of the streamer into two parts. The second mechanism is associated with the instability of the streamer in the base region, which leads to the branching of the streamer with the formation of a large number of lateral streamers closing the main channel of the streamer to the cathode. In numerical experiments, the third branching mechanism observed in experiments connected with the branching of the plasmoid in the cathode region with the closure of the space charge to the anode through the streamer system was observed. The similarity of ball lightning and plasmoid is discussed. If this similarity is confirmed, then the number of theoretical hypotheses concerning the nature of ball lightning, currently more than 200, can be drastically reduced to one described in this article
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SIMULATION OF BALL LIGHTNING IN CONDUCTING ENVIRONMENT
01.00.00 Physical-mathematical sciences
DescriptionIn this work, a model is developed to describe the formation of streamers, plasmoid, and ball lightning in a conducting medium. To describe the contribution of the conductivity currents, we modified the standard electrostatic equation taking into account the vortex component of the electric field. As a result of this generalization, a system of parabolic-type nonlinear equations is formulated that describes the formation of streamers, plasma long-lived formations and ball lightning. As is known, in laboratories it is possible to create a plasmoid with a lifetime of 300-500 ms and a diameter of 10-20 cm, which is interpreted as a ball lightning. With high-speed photography, a complex structure is detected, consisting of a plasmoid and surrounding streamers. Within the framework of the proposed model, problems are posed about the formation of a plasmoid and the propagation of streamers in an external electric field. In this model, the plasmoid is considered to be a long-lived streamer. The range of parameters in which a plasmoid of spherical shape is formed is indicated. It is established that there are three streamer branching mechanisms. The first mechanism is related to the instability of the front, which leads to the separation of the head of the streamer into two parts. The second mechanism is associated with the instability of the streamer in the base region, which leads to the branching of the streamer with the formation of a large number of lateral streamers closing the main channel of the streamer to the cathode. In numerical experiments, the third branching mechanism observed in experiments connected with the branching of the plasmoid in the cathode region with the closure of the space charge to the anode through the streamer system was observed. The results of modeling the evolution of globular clusters in a scale of hundreds of milliseconds are given. Plasma exchange recharge modes leading to the formation of a positive or negative charge of the system are found
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SPECIAL CASES OF INVERSE MATRICES
01.00.00 Physical-mathematical sciences
DescriptionThe inverse matrix for the square matrix A of order n with coefficients of some field exists, as it is known then and only then, when its determinant is not equal to zero. If the matrix A has a certain type (certain structure), then an inverse matrix A-1 should not have exactly the same structure. Therefore, it is interesting to describe such square matrices A, which have an inverse matrix A-1, having the same structure as the matrix A, under certain conditions. For example, a subdiagonal matrix with nonzero elements on the main diagonal has an inverse matrix over a field of characteristic zero, having also the form of subdiagonal matrix. Similarly, an inverse matrix towards symmetrical or skew-symmetric matrix is also symmetric or skew-symmetric accordingly. Also, the matrix inverse to non-degenerate (nonsingular) circulant will be a circulant itself, and finally, the matrix inverse to nonsingular quasdiagonal matrix D will be quasdiagonal itself, and will have the same partitioned structure as D. Thus, there is a problem of determining these types of nonsingular matrices that have an inverse matrix of the same type as a given matrix. In line with this problem in the present study it is determined such type of matrices for which an inverse matrix has the same type, at that the conditions are identified in explicit form, ensuring the nonsingularity of the matrix. The matrices of three orders are shown in detail. These results allow determining the characteristics of fields over which there are inverse matrices of the considered types
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THE RATIONALE FOR THE USE OF ELECTROMAGNETIC FIELD IN THE PRODUCTION OF SUNFLOWER OIL
01.00.00 Physical-mathematical sciences
DescriptionIn some works, the feasibility of the use of fixed and variable electromagnetic fields of different frequencies and tension in the production technology of sunflower oil are shown, but there is no theoretical justification. The possibility of electromagnetic effects is associated with the presence of polar molecules specific to organic systems. Without prejudice to the role of polar groups of terrestrial circuits, this work tries to address this challenge more comprehensively. The reason for this is the distinctive feature of the behavior of sunflower during its flowering. This characteristic is that the sunflower hat during the day changes its direction in accordance with the direction of movement of the Sun across the sky; so called "magnetism" of their attraction. To justify this effect, we have analyzed the essence of emitted photons, the Sun chemical composition and structure arrangement of seeds in a sunflower hat. Particles of light from the Sun represent a stream of photons - a wide range of electromagnetic waves of frequencies that exhibit and magnetic properties. The article shows principal macro- and micronutrients of sunflower raw materials and divides them into groups of para- , dia- , and ferromagnetic materials. In sunflower seeds, there are chemical elements: diamagnetism-C, H, N, P, S, B, Cu, Zn, J; paramagnetism-O, K, Ca, Mg, Mo, As and ferromagnetic-iron (Fe). As there is resultant force of the magnetic attraction between the sunflower hat and magnetic flow of photons from the Sun, this effect dominates the action of paramagnetics K2O ( -28.4 24.5%), CaO (7.6-17.0)%, MgO (12.3-17.9%), magnetized in an external magnetic field in the direction of the field. The presence of evident effect demonstrates that it is possible to improve a number of technological operations in the manufacture of sunflower oil using electrical, magnetic or electromagnetic fields
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SIMULATION OF A STEPPED LIGHTNING LEADER
01.00.00 Physical-mathematical sciences
DescriptionIn this work, a model is developed that describes the formation of a stepped lightning leader in a conducting medium. To describe the contribution of the conductivity currents, we modified the standard electrostatic equation taking into account the vortex component of the electric field. As a result of this generalization, a system of parabolic-type nonlinear equations is formulated that describes the formation of streamers and the lightning channel. Numerical simulation of the propagation of ionization waves in a region with a ratio of 1/100, 1/200 allows us to identify two types of stepped streamers in the form of waves of compression and rarefaction, respectively. It was previously established that there are three streamer branching mechanisms. The first mechanism is related to the instability of the front, which leads to the separation of the head of the streamer into two parts. The second mechanism is associated with the instability of the streamer in the base region, which leads to the branching of the streamer with the formation of a large number of lateral streamers closing the main channel of the streamer to the cathode. In numerical experiments, the third branching mechanism observed in experiments connected with closing the space charge to the anode through the streamer system was observed. These branching mechanisms are also revealed when the leader is propagated. The obtained results, as well as the data of numerical experiments confirm the hypothesis of the universality of the minimal model of the streamer, as well as its expansion in the form proposed by the author. Known phenomena of nature associated with the electrical discharge - streamer, plasmoid, ball lightning and stepped leader can be described within the framework of the minimal model
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ASYMPTOTICS OF ESTIMATES OF PROBABILITY DISTRIBUTION DENSITY
01.00.00 Physical-mathematical sciences
DescriptionNonparametric estimates of the probability distribution density in spaces of arbitrary nature are one of the main tools of non-numerical statistics. Their particular cases are considered - kernel density estimates in spaces of arbitrary nature, histogram estimations and Fix-Hodges-type estimates. The purpose of this article is the completion of a series of papers devoted to the mathematical study of the asymptotic properties of various types of nonparametric estimates of the probability distribution density in spaces of general nature. Thus, a mathematical foundation is applied to the application of such estimates in non-numerical statistics. We begin by considering the mean square error of the kernel density estimate and, in order to maximize the order of its decrease, the choice of the kernel function and the sequence of the blur indicators. The basic concepts are the circular distribution function and the circular density. The order of convergence in the general case is the same as in estimating the density of a numerical random variable, but the main conditions are imposed not on the density of a random variable, but on the circular density. Next, we consider other types of nonparametric density estimates - histogram estimates and Fix-Hodges-type estimates. Then we study nonparametric regression estimates and their application to solve discriminant analysis problems in a general nature space