Scientific Journal of KubSAU

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

APPLICATION OF THE MONTE-CARLO METHOD WHEN STUDYING THE PROPERTIES OF STATISTICAL TESTS OF HOMOGENEITY OF TWO INDEPENDENT SAMPLES

abstract 1541910007 issue 154 pp. 55 – 83 30.12.2019 ru 208
The instrumental methods of economics include the Monte Carlo method (statistical simulations method). It is widely used in the development, study and application of mathematical research methods in econometrics, applied statistics, organizational and economic modeling, in the development and making management decisions, in the basis of simulation modeling. The new paradigm of mathematical research methods developed by us is based on the use of the Monte Carlo method. In mathematical statistics, limit theorems on the asymptotic behavior of the considered random values were obtained for many methods of data analysis with an unlimited increase in sample volumes. The next step is to study the properties of these random values for finite sample sizes. For such a study, the Monte-Carlo method is used. In this article, we use this method to study the properties of statistical criteria for testing the homogeneity of two independent samples. We considered the most used in the analysis of real data criteria - Cramer-Welch, which coincides with the equality of the sample sizes with Student's criterion; Lord, Wilcoxon (Mann-Whitney), Wolfowitz, Van der Waerden, Smirnov, type omega-square (Lehmann-Rosenblatt). The Monte Carlo method allows us to estimate the rates of convergence of distributions of criteria statistics to the limits, to compare the properties of the criteria for finite sample sizes. To use the Monte Carlo method, it is necessary to select the distribution functions of the elements of the two samples. For this purpose, normal and Weibull – Gnedenko distributions are used. The recommendation was received: to test the hypothesis of coincidence of distribution functions of two samples, it is advisable to use the Lehmann-Rosenblatt (type omega-square) test. If there is reason to assume that the distributions differ mainly by the shift, then the Wilcoxon test and Van der Waerden criteria can also be used. However, even in this case, the omega-square type test may be more powerful. In the general case, besides the Lehmann-Rosenblatt criterion, the use of the Smirnov criterion is permissible, although for this criterion the real level of significance may differ from the nominal level of significance. We sstudied the frequency of discrepancies of statistical findings on different criteria
800 kb

IMPROVEMENT OF ACOUSTIC DIAGNOSTIC METHODS FOR HIDDEN MICRODEFECTS AND OPERATIONAL RELIABILITY OF VISCOELASTIC STRUCTURAL ELEMENTS

abstract 1541910009 issue 154 pp. 84 – 93 30.12.2019 ru 295
The economic and operational reliability of building structures to a large extent depends on the preservation of the bearing capacity of thin-walled structures, in particular, rods with viscoelastic properties. The presence of invisible microdefects in them can lead not only to a decrease in the bearing capacity, but also to the destruction of structures. For the detection of microdefects by acoustic diagnostic methods, it is necessary to know the dependence of the longitudinal strain wave velocity on the rheological properties of the structural material. Such dependences can be revealed by the construction and analysis of mathematical models describing viscoelastic deformation waves formed in rod systems made of a material with rheological properties
444 kb

THEORETICAL BASES OF A COURSE MOTION FOR A TWO AXLES AGRICULTURAL VEHICLE ACCORDING TO WHEELS SLIPPING

abstract 1541910010 issue 154 pp. 94 – 103 30.12.2019 ru 175
The problem of linear motion of agricultural transporting vehicle (ATV) without satellite systems is a complex and difficult task. The consequences of non-linear movement associated with irregularity fertilizing, non-compliance between the rows and irregularity plowing leads which will leads to unnecessary costs for operating materials, which will causes significant economics damage to agricultural enterprises. In this case. In this article, we have presented theoretical foundations of simulation modeling of the course motion of the ATV taking into account wheel slipping for analyzing the effects of non-linear motion. There were also some results of checking their adequacy from field tests
183 kb

METHODOLOGY OF OPTIMAL PLACEMENT OF TRADE NETWORK OBJECTS

abstract 1541910011 issue 154 pp. 104 – 118 30.12.2019 ru 233
The article outlines the idea of a methodology for locating distribution centers of a spatially distributed distribution network without restrictions on the territory. In the past fifteen years in Russia, the profitability of offices and retail space has been significantly higher than logistic complexes. At present, it is possible to talk about a change in the investment attractiveness of the segment of distribution centers and storage facilities. The method consists in solving three problems: determining the number of distribution centers that need to be placed using the method of comparing options; determination of the best locations for placement of distribution centers using the ant colony algorithm; identification of the best location from the previously determined ant colony algorithm using the penalty function method. This method of optimal placement of objects of a spatially distributed complex can be applied not only to the distribution network, but also to any transport company with distribution centers, for example, a logistics company, delivery services, etc.
165 kb

INFLUENCE OF WEATHER CONDITIONS ON EFFICIENCY OF MINERAL FERTILIZERS APPLICATION IN CORIANDER SEEDS ON BLACK LEACHED SOIL

abstract 1541910012 issue 154 pp. 119 – 131 30.12.2019 ru 184
The article presents data from 3-year observations of the weather conditions influence on the effectiveness of applied fertilizers in the crops of the Yantar variety of coriander on leached black soil (chernozem) under the conditions of land use at the training and experimental station of the Stavropol State Agrarian University. The materials presented in the article indicate that the agrometeorological conditions of 2016 and 2017 as a whole were most favorable for the formation of a coriander crop. As studies have shown, the amount of precipitation during the spring-summer period of the growing season of the crop was 337 mm, which is 11% higher than the long-term average. The year 2018 in terms of climatic indicators turned out to be significantly worse than the previous two years, the amount of precipitation during the coriander vegetation period turned out to be 125 mm or 58% lower than the long-term average, which significantly affected the crop yield this year. In the most optimal agroclimatic indicators in 2016, the maximum increase in crop productivity was noted on the N60P60K60 variant - 0.49 t / ha, on the same option in moistened 2017, the increase level was 0.39 t / ha. Last year2018 was marked as extremely arid, the maximum increase in coriander yield was noted on the option with P60 and amounted to 0.35 t / ha. It was established that the maximum increase in the yield of coriander oil seeds on average in the experiment on leached chernozem was achieved with the options: P60 is 0.37 t / ha, N60P60 is 0.41 t / ha, N60P60K60 is 0.34 t / ha, which significantly higher than other fertilized experience options. The economic efficiency of the coriander seeds production, depending on the types and combinations of minerals, turned out to be most effective when applying a single mineral fertilizer, P60, compared with other options for experience, an increase in profit to 17500 rubles and the level of profitability of production by 23%
1356 kb

FINANCIAL RISK WARNING AT OIL PRODUCTION COMPANIES

abstract 1541910013 issue 154 pp. 132 – 154 30.12.2019 ru 218
This article is devoted to a problem of effective management of a financial and economic condition of companies on the example of the enterprises of oil products supply. We consider questions of support of adoption of management decisions which concern stabilization of a financial condition of the company and as a result of decrease in financial risks. The article also provides a description of the program complex called FESP_ON developed by the authors allowing to carry out the profound complex assessment of a financial and economic condition of Societies of oil products supply
154 kb

PROJECT MANAGEMENT PROCESS IMPROVEMENT DIAGNOSIS OF THE STATOR WINDINGS OF ELECTRIC MOTORS VOLTAGES ABOVE 1 KV

abstract 1541910014 issue 154 pp. 155 – 160 30.12.2019 ru 196
The management of the process of implementation of projects at the refinery should be carried out comprehensively. To improve the diagnostic system of insulation of the stator windings of electric motors with a voltage above 1 kilovolt, it is necessary to involve specialists of all sub-divisions. This will allow a comprehensive approach to the problem of reducing the intensity of labor, and, consequently, to reduce the norms of time for performing operations provided for by the technological process. It is proposed to create a project team consisting of the following specialists: General Director, chief designer, chief electrician, lead engineer for adjustment and testing, Deputy Director for production, head of the Department of labor and wages, chief economist. In addition, the design should involve the heads of shops and sites, directly managing and organizing processes in the workplace. Domestic and foreign experience shows that the introduction of diagnostic tools is one of the most important factors in increasing the economic efficiency of the use of equipment in the industry. Purpose of diagnostics is identification and prevention of failures and malfunctions, maintenance of operational indicators within the established limits, forecasting of a condition for the purpose of full use of a resource
372 kb

INFLUENCE OF BASIC PROCESSING AND MINERAL FERTILIZERS ON AGRIBIOLOGICAL INDICATORS OF WINTER BARLEY

abstract 1541910015 issue 154 pp. 161 – 171 30.12.2019 ru 269
The article presents the results of studies on the influence of mineral fertilizers and basic tillage in the technology of cultivating winter barley on its agrophysical properties. Object of research - plants of winter barley cultivar called Rubezh. Soil - typical low-humus heavy-duty leached chernozems. In the experiment, the influence of two factors on the formation of the productivity of winter barley was studied. Factor A - the method of primary tillage: option 1 (A0) - dump plowing to a depth of 20-22 cm (control); option 2 (A1) - chisel for 20-22 cm; option 3 (A2) - disk peeling at 8-10 cm; option 4 (A3) - zero treatment (direct sowing). Factor (B) - fertilizer rate: option 1 (B0) - without fertilizing (control); option 2 (B1) - recommended norm N40P40 + N20; option 3 (B2) - double norm N60P60 + N40. According to the data of our experiments, the general orientation in the technology of cultivating winter barley has been revealed, during the entire growing season, the height of its plants decreases while the tension of its main processing decreases - from 89.6-90.3 cm for deep processing to 87.7 cm for surface processing and up to 73.7 cm at zero. Moreover, the type of tillage did not affect the stem of winter barley plants of the Rubezh variety. At the same time, on all tillage options, one can notice the dependence of the height and density of the stand on the dose of fertilizer application - from 80.6 cm in the control to 84.4 cm at the recommended dose of mineral fertilizers and up to 91.4 with a double. It was also noted in relation to the density of plant standing - from 335 pcs / m2 in the control to 358 pcs / m2 with the recommended dose of mineral fertilizers and up to 376 pcs / m2 with a double
170 kb

SCIENTIFIC AND PEDAGOGICAL TEAM’S RECOGNITION DIAGNOSTICS BASED ON THE ANALYSIS OF THE RESEARCH ACTIVITY RESULTS

abstract 1541910016 issue 154 pp. 172 – 186 30.12.2019 ru 234
The research purpose is identification and justification of the scientific team’s recognition citation-based criteria. Such parameters of the educational environment as modality, latitude, social activity, social coherence, intensity, maturity etc. are assessable on the basis of the primary information about the scientific team’s research activity results. The authors of this article prove that the data about cross-citations within a scientific team is the primary information about the scientific and pedagogical team members’ recognition of their social system (such information is obtainable from modern scientometric databases, e.g. Russian Science Citation Index). The new scientific results of this research are the identified citation-based criteria for the scientific team’s recognition. The theoretical significance of these results is the possibility of using them as a scientific basis for further research in the sociology of science and for the development of the small social systems functioning models; the practical significance is the possibility to analyze the factors for the success of scientific and pedagogical teams’ research activity (i.e. applicability for the research activity monitoring systems). The research methods are: the methods of set, relations and graph theory, the methods of qualimetry, mathematical statistics (including the scree-plot method) and linear. The research methodology is based on the sociological approach (viewing the scientific and pedagogical team as a well-established social system), the qualimetric approach (declaring the necessity for the multicriterial diagnostics of scientific and pedagogical team’s recognition) and the probabilistic and statistical approach (viewing the scientific and pedagogical team’s recognition citation-based diagnostics as a statistic measurement)
2251 kb

INFORMATION AND COGNITIVE TECHNOLOGIES IN QUALITY OF LIFE MANAGEMENT THROUGH INVESTMENTS IN AGRICULTURE: SOLVING PROBLEMS OF FORECASTING AND DECISION-MAKING

abstract 1541910017 issue 154 pp. 187 – 198 30.12.2019 ru 256
In their previous works, the authors solved the problem of cognitive-target structuring and formalization of the subject area, as well as the synthesis and verification of statistical and system-cognitive models. This work is devoted to the application of these models to solve the problem of forecasting the impact of the volume and direction of investment in agriculture on the economic component of the quality of life of the population of the region. This work is devoted to the use of previously created and verified models to solve the problem of decision-making on the volume and direction of investment in agriculture, improving the quality of life of the population of the region
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