Formation of engineering higher education institution and restoration processes of higher agricultural school and inMinskare closely interrelated with each other. TheBelarussianNationalTechnicalUniversityand theBelarussianStateAgriculturalAcademyare celebrating their jubilees in 2010.
ARCHITECTURE AND CIVIL ENGINEERING
Civil engineering material science has accumulated a great amount of scientific data on corrosive processes occurring in the NPS concrete structures (including the Bushehr NPS, Islamic Republic of Iran) due to environmental conditions.
This practical material creates appropriate prerequisites for generalizations, presentation of results in the form of mathematical models permitting to make calculations on durability of the NPS concrete and reinforced concrete structures with the required accuracy.
A calculative-graphic method for designing structure of heavy concrete with chemical additives is developed in the paper. The paper presents a system of concrete frost resistance forecasting which is based on estimation of structural and mechanical characteristics of a material. Accuracy of calculations shown in the paper is rather sufficient for practical purposes.
A methodology for determination of estimated performance of main road-building materials (asphalt concrete and сold recycled material) within wide range of temperature and strain rate, is developed in the paper and it allows to obtain the whole spectrum of parameters required for calculation of a road pavement structure with minimum number of test results. This technique can be useful in designing material and pavement structure during its repair while using the method of cold in-place recycling because it enables significantly to reduce a number of laboratory tests. The methodology has been implemented as a computer program for its practical application.
METALLURGY. МЕТАL WORKING. MECHANICAL ENGINEERING
The paper considers wall thickness changes of a round billet in the pipe expansion process with subsequent flanging owing to thinning of this wall in the strain zone and bearing strain of an internal edge. Equations for calculation of thinning value are given in the paper.
The paper proposes an analytical model for topography of a magnetic field while making magnetic and abrasive machining of discontinuous surfaces. Topography analysis has made it possible to determine a rational configuration of an operational zone of electromagnetic system pole pieces while machining gear wheel.
The paper considers concrete industrial thermal technological processes where the problem concerning their control is necessary to investigate as a problem pertaining to control of systems with distributed parameters. A structural scheme for solution of the problem concerning optimization of thermal technological processes is proposed in the paper.
The paper presents results of investigations on dependence of dielectric, electromechanical and elastic properties of BNпсф polycrystals (sphalerite) with texture axis [111]сф, obtained from pyrolitic boron nitride BNпг on annealing temperature up to 2173 К. Peculiar features concerning changes of the given properties in the zone of low-temperature annealing 700–773 К and phase transformation BNпг — BNпсф are shown in the paper.
INSTRUMENT ENGINEERING. INFORMATICS
The paper proposes methods for preliminary machining of sawing disk lateral surfaces before their charging that provide formation of micro-relief grains on them which are favorable for introduction. The experimental data reflect influence of accepted methods for machining initial disk blanks on abrasive ability and wear resistance of diamond-containing coatings which are obtained on them with the help of charging.
The paper provides a design description of a tool used for polishing balls made of brittle materials between bottom driving disk and two rings. An external stationary ring has a ring turning of rectangular profile that helps the ring to be based directly on the balls which are to be polished and take self-aligned position in relation to tool rotation axis. Forces acting on the balls in the points of contact with the tool with due account of friction against a separator and conditions of ball sliding along ring working surfaces are determined in the paper. Dependence for determination of stationary and driving ring load ratio when balls are sliding along two contact surfaces of the tool is ascertained in the paper. The paper contains recommendations on selection of modes for ball polishing at its initial and finishing stages.
The paper considers sources of uncertainties appearing while making measurements within SHF range. Mathematical models and algorithms for uncertainty calculation at distance calibration of terminating power and digital frequency meters are proposed in the paper.
TRANSPORT
Time norms on diagnostics of load-lifting crane units and parts with expired service life in 2007. have been developed and introduced on the basis of statistical data collected at technical diagnosing of various load-lifting crane models under various weather conditions and which are in operation on theBelarusrailway.
POWER ENGINEERING
The paper presents an algorithm for optimization of thermal load distribution among heat-sources in the system of centralized heat supply. The algorithm can be used while elaborating plans for development of heat supply systems in cities and settlements.
HUMANITIES AND SOCIO-ECONOMIC SCIENCES
Theoretical and methodological comprehension of customs regulation place and role in provision of trade and transport activity under conditions of world integration processes is considered in the paper.
The essence of such economic categories as «customs policy», «customs regulation», «customs and tariff regulation», «customs business» is ascertained with the help of justified argumentation, clear conception approaches.Characteristics of a project can change during its construction. It is necessary to decrease a negative influence of such changes. In order to reveal the influence a methodology for cost evaluation of a project having dynamic characteristics is proposed in the paper. The methodology is developed on the basis of a standard scheme used for evaluation market building cost prior to and after making changes. The changes that cause an increase of the market cost are considered as improvements, and the changes that entail decrease or do not influence on the market cost are considered as deteriorations. Due to this an investor applies more efficiently leverages for management of investment and construction project.
ISSN 2414-0392 (Online)