Scientific Journal of KubSAU

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

MATHEMATICAL MODELING OF MTU TENSILE LOAD

abstract 1011407024 issue 101 pp. 424 – 437 30.09.2014 ru 1129
The article is devoted to mathematical modeling of random process that occurred in tensile load of serial and experienced MTU. The efficiency of EDM application in transmission is discussed
173 kb

MATHEMATICAL MODELING OF MUTUALLY BENEFICIAL RELATIONS BEETWEEN RAW MATERIAL PRODUCERS AND PROCESSORS BASED ON NONLINEAR DEMAND FUNCTION

abstract 1101506110 issue 110 pp. 1692 – 1707 30.06.2015 ru 837
Agricultural producers interested in marketing of raw materials, whereas processing companies are interested in the establishment of raw material zones, providing capacity utilization; therefore, the establishment of sustainable linkages between producers and processors of raw materials is an objective necessity. In the article, with the help of mathematical methods we examine the conditions of mutually beneficial economic relations between agricultural producers and processing enterprises. Mathematical model for estimating the profits of the company is built of the following conditions: producers sell processing plants raw materials, determined by the coefficient of the interest in the partnership at an agreed purchase price, and the remaining raw materials are processed, so they can sell their products independently. Profit of the processing plant is determined by the mathematical model. To describe the nonlinear market-based sales of goods from its retail price we used a hyperbolic demand function
109 kb

MATHEMATICAL MODELING OF PSP SENSOR SYNCHRONIZATION ON LOW QUALITY CHANNELS

abstract 1541910003 issue 154 pp. 17 – 22 30.12.2019 ru 204
The purpose of this work is to find the boundary estimate of the synchronization of PSP sensors in low-quality channels according to the method of the test segment (OST), independent of the distribution of errors in the channel
544 kb

MATHEMATICAL MODELING OF SPECIAL ELECTRIC DRIVES FOR THE EQUIPMENT OF OIL AND GAS BRANCH

abstract 1321708072 issue 132 pp. 926 – 940 31.10.2017 ru 270
Creation of new types of special electric actuators for the oil and gas industry implies development of new approaches to simulation, design of the considered types of electric actuators. In addition, it requires development of new algorithms for creation of a complex of application programs of computer-aided design of special electric actuators. As process of simulation is quite labor consuming, it is offered to realize it gradually. In this article, the question of mathematical simulation of special electric actuators for the equipment of oil and gas branch using methods of electromagnetic conversion of energy is considered. Results of mathematical simulation were realized in the form of the program products, which are a part of system of computer-aided design
250 kb

MATHEMATICAL MODELING OF SYNCHRONOUS MOTORS FOR AGRICULTURAL ELECTRICAL POWER SUPPLY SYSTEMS

abstract 0871303024 issue 87 pp. 312 – 323 30.03.2013 ru 1449
The article presents mathematical models for both salient pole and non-salient pole synchronous motors represented as electrical circuits with dependent sources, which can be used for the transient analysis of agricultural electrical power systems
207 kb

MATHEMATICAL MODELING OF THE RELATIONS OF PARTNERS IN MODERN FORMS OF INTEGRATION OF AGRICULTURAL MANUFACTURERS AND PROCESSING-FORMING ENTERPRISES

abstract 1301706083 issue 130 pp. 1137 – 1159 30.06.2017 ru 591
The integration of producers of raw materials and its processors into the agro-industrial complex is connected with the social division of labor, its specialization, the need for interaction between specialized branches and types of agro-industrial production. Agrarian enterprises are united in an effort to reduce the risk, the emergence of which depends on the climatic conditions, the spontaneity of the agricultural market, the dictates of processing enterprises, the need to increase the competitiveness of production. In the Russian practice, there were various organizational forms of integration, differing in the nature of economic ties between participants, the degree of independence of the enterprises entering the association, the combination of centralization and decentralization of management. Conventionally they are divided into associative - "soft" and corporate - "hard." The "soft" forms of association include as-association, union, non-profit partnership and strategic alliance. They can effectively function at the interregional level. A rigid type of integration ties is characteristic for combines, concerns, trusts, holdings. Agricultural consumer cooperatives are voluntary associations of legal entities and individuals residing or operating in a certain rural area on the basis of membership and pooling of money units in order to meet the needs of members in credit resources and other banks services. The conditions for the emergence of sustainable integrated associations in the agroindustrial complex require qualitative and quantitative analysis based on mathematical modeling
295 kb

MATHEMATICAL MODELING OF THE UNIFORMITY OF WATERING WITH A SPRINKLING MACHINE OF CONTINUOUS PROGRESSIVE MOVEMENT ACCORDING TO THE RESULTS OF THE TEST OF THE UNIT WITH A RADIAL METHOD

abstract 1281704014 issue 128 pp. 229 – 239 28.04.2017 ru 324
The aim of the study was to improve evaluation of the uniformity of irrigation with a machine of continuous translational motion, according to the test results of the apparatus with radial methods. Research method – mathematical modeling of the running of four machines of circular actions on a device of continuous translational motion using the result of the tests of the device with a radial method. The algorithm of calculation, recommended by the standard ISO 7749-2-2004, has been improved to minimize manual calculations and measurements. The algorithm is implemented in a computer program. Program of CDU(B) implements an advanced algorhythm. The program calculates a matrix of irrigation doses on meter squares area of spray irrigation between the positions of the two devices. The progressive movement of the machine is modeled by summing the doses in column-major order with constant X. At vector doses after the passage of the machine, it calculates the coefficient of uniformity of irrigation by Christiansen. The calculation is performed at different steps of the installation of devices, and so it determines the optimal location of them. The improved algorithm of calculating the figures of sprinkling uniformity using the test results for devices using a radial method was implemented in the program of the CDU(A) [1]; it allows to choose the optimal step for installation of devices. The algorithm of calculating the uniformity in the step of installation of the apparatus on the pipeline which is greater than the radius of the irrigation apparatus simulates the operation of two devices. During the installation step of the apparatus of smaller radius than irrigation apparatus, we model the work of four adjacent devices. The optimal step of installation of i-Wob is 14.5 meters, which is 1.75 times greater than the radius of the irrigation system and 1.5 times greater than the pitch of stationary devices with the same tolerance on the uniformity. Two-nozzle devices, which assessment standard does not meet the requirements of the uniformity of irrigation at the drive of the translational motion ensures a better distribution in the pitch of less than 24 meters
359 kb

MATHEMATICAL MODELING OF THE INFLUENCE OF SURFACE MORPHOLOGY OF HETEROGENEOUS ION-EXCHANGE MEMBRANE TO THE ELECTROCONVECTION

abstract 1041410046 issue 104 pp. 630 – 643 30.12.2014 ru 1117
This article continues the works [1,2], devoted to the theoretical study of the basic laws of electroconvection caused by natural or artificial inhomogeneous conductivity of ion-exchange membranes in a smooth rectangular channel electrodialysis desalination unit. For this purpose, a mathematical model was created for a binary electrolyte electroconvection at overlimiting current modes in the form of a boundary value problem for a coupled system of the Nernst-Planck-Poisson and Navier-Stokes equations. We have studied the influence of heterogeneity on the ion-exchange membranes and ion transport electroconvection salt, calculated currentvoltage characteristic. The possibility of intensification of mass transfer due to the surface modification of ion exchange membranes was also shown
353 kb

MATHEMATICAL MODELING OF THE WORKING PROCESS OF LEVER BREAKER

abstract 0751201082 issue 75 pp. 1067 – 1076 27.01.2012 ru 1411
The dependences of the distribution of stump roots, allowing to model stump parameters to assess the difficulties of stumping are given, in requirements justification for stumping equipment. Based on the analysis of lever breaker working process, the differential equation of lever motion is got, which connects the moments acting on it and breaker performance modes and allows to set the parameters and modes of lever breaker in stumping of various sizes and species of wood
571 kb

MATHEMATICAL MODELING OF WORKING PROCESS IN ROLLER-DIE PELLET MILL WITH BUTT RESTRICTION OF WEDGE-SHAPED SPACE

abstract 0751201042 issue 75 pp. 521 – 544 27.01.2012 ru 1921
In this article, the direction of an improvement of the working process of roller-die pellet mills with a ring dies by butt restriction of wedge-shaped space by addi-tional contact surfaces is proved. The mathematical model of the process of pressure granulation (pelleting, extrusion agglomeration) of plant raw materials in the conditions of the closed wedge-shaped space between a die and each of press rollers is presented. On the ba-sis of the analysis of the mathematical model possi-bility of significant increase of capacity and decrease in energy intensity of pellet mills having additional contact surfaces in the form of restrictive rings is shown
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