Scientific Journal of KubSAU

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

ADAPTIVE TIME SERIES MODELS OF A MOUNTAIN RIVER LEVEL

abstract 1141510109 issue 114 pp. 1517 – 1530 30.12.2015 ru 893
The article presents a technique of short-term forecasting of water level in the river bed of a mountain type using Markov’s chains
295 kb

ADDITIVE-MULTIPLICATIVE MODEL FOR RISK ESTIMATION IN THE PRODUCTION OF ROCKET AND SPACE TECHNICS

abstract 1021408004 issue 102 pp. 78 – 111 31.10.2014 ru 1209
For the first time we have developed a general additive-multiplicative model of the risk estimation (to estimate the probabilities of risk events). In the two-level system in the lower level the risk estimates are combined additively, on the top – in a multiplicative way. Additive-multiplicative model was used for risk estimation for (1) implementation of innovative projects at universities (with external partners), (2) the production of new innovative products, (3) the projects for creation of rocket and space equipmen
148 kb

ALGORITM OF CALCULATION OF DETERMINANTS OF PREFRACTAL GRAPHS WITH THE FULL PRIMERS, KEEPING OLD EDGES CONTIGUITY

abstract 0871303044 issue 87 pp. 552 – 562 30.03.2013 ru 1976
In the article, the algorithm – a recurrent formula for calculation of determinants of prefractal graphs with the full primers, keeping old edges contiguity in a trajectory was received
1854 kb

AMPLITUDE-FREQUENCY AND AMPLITUDEVELOCITY CHARACTERISTICS OF A RIGID OSCILLATING INCLUSION MOVING WITHIN A TWO-LAYER ISOTROPIC MEDIUM

abstract 1331709035 issue 133 pp. 448 – 466 30.11.2017 ru 629
The article is dedicated to a numerical investigation of a plane problem of the oscillation amplitude of a buried source, depending on the frequency and motion speed in various isotropic media. Three types of the medium are considered: a two-layer package with a rigidly fixed base, a two-layer package with a mechanically free base, a half-space. The source, in the form of a stress jump simulating a rigid inclusion of small dimensions, moves in the interface plane at a constant speed. Homogeneous boundary value problems are considered in a moving coordinate system associated with a source. The solution method is based on the usage of integral Fourier transforms, the method of direct contour integration and algorithms for constructing symbols of Green's matrices. The method of direct contour integration significantly simplifies calculations in comparison with the traditional approaches to the calculation of Fourier integrals. We have presented calculations of nine amplitude-frequency and amplitude-velocity characteristics for different combinations of medium and source types, that give an exhaustive qualitative and quantitative description of the solutions for boundary value problems in a wide range of velocities and frequencies. Comparative analysis of calculations showed a primary influence of the type of an elastic medium on the investigated characteristics, as well as the large influence of the source type. Which, in turn, revealed some substantial connections between the boundary value problems with a moving source and the corresponding problems with a stationary source
224 kb

AN ALGORITHM AND A PROGRAM FOR CALCULATING THE NUMBER OF COMBINATIONS FOR LARGE NUMBERS WITHOUT CALCULATING THE INTERMEDIATE FACTORIALS BY THEIR DECOMPOSITION INTO PRIME FACTORS AND ABBREVIATIONS

abstract 1181604110 issue 118 pp. 1662 – 1671 29.04.2016 ru 837
Classical combinatorial formula to calculate the number of combinations from n on m: C(n,m)=n!/(m!(nm)!) involves the intermediate calculation of factorials, which is often impossible when n>170, due to limitations in the capacity of numbers that are used in programming languages and created through these systems. However, in some cases it is necessary to calculate the number of combinations for n and m much larger than this limit, such as when a value greater than 10000. In such cases, there is a definite problem, which manifests itself, for example in the fact that many on-line services meant to calculate the number of combinations with these parameters do not work properly. In this article, we present its solution in the form of an algorithm and software implementation. The essence of the approach is to first decompose the factorials into prime factors and reduce them, and then to produce multiplication. This approach differs from those cited in the Internet
144 kb

ANALYSIS OF APPLICATION CONDITIONS OF KOLMOGOROV’ PROBABILITY THEORY

abstract 0981404108 issue 98 pp. 1513 – 1526 30.04.2014 ru 1892
The article analyses well-known approaches to the explanations of Kolmogorov's conditions for probabilities studied in applications. It discusses better-founded explanations, offers and looks into new approaches to the explanations of connectedness of the conditions
447 kb

ANALYSIS OF EXPERT ORDERINGS

abstract 1121508002 issue 112 pp. 21 – 51 30.10.2015 ru 1118
In various applications it is necessary to analyze some expert orderings, ie clustered rankings of examination objects. These areas include technical studies, ecology, management, economics, sociology, forecasting, etc. The objects may make samples of the products, technologies, mathematical models, projects, job applicants and others. We obtain clustered rankings which can be both with the help of experts and objective way, for example, by comparing the mathematical models with experimental data using a particular quality criterion. The method described in this article was developed in connection with the problems of chemical safety and environmental security of the biosphere. We propose a new method for constructing a clustered ranking which can be average (in the sense, discussed in this work) for all clustered rankings under our consideration. Then the contradictions between the individual initial rankings are contained within clusters average (coordinated) ranking. As a result, ordered clusters reflects the general opinion of the experts, more precisely, the total that is contained simultaneously in all the original rankings. Newly built clustered ranking is often called the matching (coordinated) ranking with respect to the original clustered rankings. The clusters are enclosed objects about which some of the initial rankings are contradictory. For these objects is necessary to conduct the new studies. These studies can be formal mathematics (calculation of the Kemeny median, orderings by means of the averages and medians of ranks, etc.) or these studies require involvement of new information from the relevant application area, it may be necessary conduct additional scientific research. In this article we introduce the necessary concepts and we formulate the new algorithm of construct the coordinated ranking for some cluster rankings in general terms, and its properties are discussed
398 kb

ANALYSIS OF FINANCIAL AND ECONOMIC STATE OF CONSTRUCTION ENTERPRISES WITH THE METHODS OF MULTIVARIATE STATISTICAL ANALYSIS

abstract 0701106016 issue 70 pp. 207 – 220 30.06.2011 ru 2555
In the article an effective system of an estimation of a financial and economic status of the factories of a building sector of Krasnodar region (Armavir district), based on use of methods of the multidimensional statistical analysis is introduced. The programmatic complex "FAP-stroi", including MS Excel plug-in, macros of «Statistica 6» and exterior processing of «1С: Enterprise 8» is built
188 kb

ANALYSIS OF METHODS OF GENERATION OF TIME SERIES WITH LONG-TERM CORRELATION STRUCTURE

abstract 0741110027 issue 74 pp. 312 – 322 30.12.2011 ru 2143
This article gives a comparative analysis of six modeling techniques of fractal differential noise, including: direct definition method, the method of Hosking, the method of Davis and Hart's, the circulant embedding method, Paxson method and method of spectral simulation. Furthermore, the algorithms are given for the analysis and the method of estimation of Hurst`s parameter is selected, this method is the main criterion of quality when comparing the above mentioned methods of fractal differential noise
181 kb

ANALYSIS OF THE PROCESSES CAUSED THE MAGNETIC FIELD INFLUENCE ON A STRUCTURE AND PROPERTIES OF WATER

abstract 0811207048 issue 81 pp. 635 – 647 30.09.2012 ru 1764
The scientific publications review about a magnetic field influence on cluster sizes and their concentration was carried out. These structural changes are attended by the water system physicochemical properties changes. For example, the surface tension coefficient changes. It is shown, that the conductivity and the dielectric constant of water change in a weak magnetic field. It is provided, that characteristics of water activated by a magnetic field can save in a significant time
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