№ 58(4), April, 2010
Public date: 28.04.2010
Archive of journal: Articles count 32, 52 kb
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01.00.00 Physical-mathematical sciences
TURBULENCE THEORY AND ROUGHNESS DENSITY EFFECT MODEL
01.00.00 Physical-mathematical sciences
DescriptionThe model of the turbulent boundary layer over a rough surface is presented. The model is based on the special type of transformation of the Navier-Stokes equation. The turbulent boundary layer in this model is considered as a flow above the rough surface gener-ated by the viscous sublayer (the dynamic roughness effect). The roughness density effect on the shift of the mean velocity logarithmic profile has been estimated in the case of 2D and 3D roughness elements
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THEORY AND CONSTANTS OF WALL TURBULENCE
01.00.00 Physical-mathematical sciences
DescriptionThe completely closed model of wall turbulence was derived directly from the Navier-Stokes equation. The fundamental constants of wall turbulence including the Karman constant have been calculated within a theory. This model has been developed also for the accelerated and non-isothermal turbulent boundary layer flows. The estimated mean velocity, temperature and impurity concentration profiles as well as the spectral characteristics of the streamwise velocity component are to be shown in a good agreement with the experimental data
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PROBLEM OF INCREASING THE INFORMATION SYSTEMS EFFECTIVENESS IN CONTEMPORARY CONDITIONS
DescriptionThe increase of conceptual system for the description of the efficiency improvement problem has been submitted for consideration. The composition and structure individual criteria and requirements for variant formalization of complex criterion information systems effectiveness as a technical system and means of analysis and information processing have been presented as the methodological initiative in this article
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CONCEPT OF THE INTELLIGENT TECHNOLOGIES FOR INCREASING THE INFORMATION SYSTEMS EFFECTIVENESS
DescriptionThe concept of the intelligent technologies development considering characteristic estimation and preference modeling of a decision-making person as a criterion of information system effectiveness through the system analysis has been formulated in the article
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THE INFLUENCE OF RECIPES COMPONENTS IN FORMED PRESERVES ON THEIR REOLOGICAL PROPERTIES
DescriptionThe investigation results in influence of recipes components of different kinds minces on their structurally-mechanical properties are presented
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CONSTRUCTION-TECHNOLOGICAL IDEAS FOR PROTECTION AND PLANTS CARING
DescriptionThe article presents the analysis of mechanize processes for chemical protection of plants and the new construction of spraying with low gallonage, a new method and water solution and machine for address painting at litter plants by organic glue with chemical destroy, and new grass cutter with address painting of litter plants by organic glue with chemical destroy, and new cutter designed to destroy weeds with electric current
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Description
The article presents the analysis of mechanize processes of soil processing and new constructions of universal chisel loosening and combination sowing unit for seedbed soil structures loosening
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Description
An example of expert analysis method of preventive and corrective actions of a major gas transmission company, aimed at environmental improvement has been shown
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06.00.00 Agricultural sciences
06.00.00 Agricultural sciences
DescriptionAt the contaminated by Аmbrosia artemisiifolia fields, a mineral food increase promotes decrease in productivity of sunflower in a greater degree
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PREDOMINANT WEEDS AND THEIR INJURIOUSNESS IN SUNFLOWER CROPS
06.00.00 Agricultural sciences
DescriptionCompetitive relations between various kinds of weeds in sunflower crop and influence of connatural factors on its constipation are considered. Specific weight of each kind of a weed and its change throughout a vegetative period, and also influence of gramineous weeds on efficiency of breeds and hybrids is defined. The economic threshold of injuriousness of gramineous weeds in sunflower crops is defined