The paper proposes a variation and differential approach to calculation of elastic  beam  plates located on physically nonlinear heterogeneous foundation. A special attention is paid to justification pertaining to selection of elastic foundation model. The model of finite thickness elastic layer with modulus varying under nonlinear law is represented. Nonlinear statement of boundary-value problem is realized by the method of elastic solutions in the field of small elastic and plastic deformations. Numerical approbation of calculation results is carried out for laminated foundations with the help of MATHEMATICA 6.0.

On the basis of the analysis of the existing technology applied for machining external working surface of hydraulic cylinder rods the paper advances prospective machining processes that presuppose finishing turning and surface plastic deformation through pulse and force vibro-rolling and that make it possible to expand technological possibilities of machining operations in respect of higher accuracy and quality of the machined surface. The presented data allow to predict machining process of such parts as shafts at the designing stage of a technological process.

 

The paper proposes methods for improvement of coating quality which are obtained with the help of electric contact sintering of powders. These methods presuppose heating of metallic powder located between a part and a roller electrode at the expense of thermal energy released by electric current with active resistance. Stabilization of properties along length of a surface to be hardened is obtained with the help of temperature regime regulation in the sintering zone and uniformity of properties along width is ensured by technical solutions that create favourable conditions for formation of edge parts of the sintered layer. The preliminary powder packing using an effect of “flowing wedge” and two-stage heating significantly improve physical and chemical properties of the coatings.

 

The paper presents results of the investigations on evaluation of logway resistance which are used for drawing cord wire made of tungsten-containing hard alloy. It has been shown that complicated loading conditions lead to fracture of a tool surface and these conditions are attributed to the action of various mechanisms: wearing due to high local stresses and deformations, fracture due to stretching stresses at logway expansion, small-cycle fatigue, heat shock etc. It is proposed to evaluate logway serviceability by such indices as hardness, strength and fracture viscosity and an amount of bundle and size of tungsten carbide grain influence on these indices.  As an alternative material to a hard alloy it is advanced to use a diamond-silicon carbide composite. It is shown that a preliminary protection of diamond crystals with the help of a-SiC nano-coating makes it possible to obtain super-hard material. Its fracture viscosity can be compared with the fracture viscosity of a hard alloy and the composite out-performs a hard alloy in respect of wear characteristics that ensures rather good prospects for its application for manufacturing logways

The structure and properties of cutting diamond tools subjected to thermo-hydro-chemical treatment are examined in the paper. The process involves a chemical treatment of tools in a specially prepared aqueous suspension of oxides Ti, Mo and other ingredients and subsequent heat treatment (minimal process temperature 130 °C). Thermo-hydro-chemical method permits to increase a wear resistance of cutting diamond tools by the factor of 1.3–4.0 in comparison with traditional one.

The paper considers possibilities to apply magnetic-abrasive machining method as one of the final operations for polishing flat  surfaces  of  silicon  wafers.  A  mathematical  model has  been  built  that reflects main principles of tool-work-piece interactions. A methodology has been developed that permits to give both qualitative and quantitative evaluation of material removal rate. Optimization of technological parameters for a 3905-model machine tool has been carried out with the help of a special software. It has been proved both in theory and experiments that applying magnetic and abrasive polishing of silicon wafers average value of planeness deviation corresponds to SEMI standards.

 

Empirical dependences for calculating reliability and mass of an aviation engine are obtained with the help of a regression analysis method and test of the obtained expression adequacy has been carried as well.

A model for degradation of the effective, elastic and heat-conducting material properties of engine parts due to spreading growth in physical and mechanical properties in comparison with data-sheet values in the process of operation without continuity violation has been developed and described in the paper. The paper also presents a model for emergence and accumulation of such damages as micro-pores, micro-cracks. The paper evaluates a critical concentration of damages with due account of a percolation theory at which a cluster-crack is formed in some local space.

The paper considers a tectonics influence on construction and operation of engineering structures on the territory of Belarus.  An example of studying  tectonic  fracture zones  in  the  Soligorsk  mining region with disturbed geological medium is given in the paper. The paper contains conclusions on necessity of obligatory account of geo-dynamic factors at all stages of constructing industrial projects, pipe-line transport and automobile roads.

The paper considers algorithms of designing a roadway covering for virtual test of mobile machine movement dynamics; an algorithm of forming actual values of forces/moments in «road–wheel–car» contact and their derivatives, and also a software for virtual designing of mobile machine dynamics.

The paper proposes a methodology for calculation of a radiator cooling surface with due account of heat transfer non-uniformity on depth of its core. Calculation of radiator cooling surfaces of «Belarus-1221» and «Belarus-3022» tractors has been carried out in the paper. The paper also advances standard size series of radiators for powerful «Belarus» tractor type.

The paper considers improvement of dynamic properties of servo-distributor using mathematical modeling method.  Design parameters of  the  distributor  that  ensure  its  high  efficient operation have been determined with the help of  multi-factor calculative for non-linearity criteria of velocity characteristic.

The paper considers a possibility to involve bio-gas generated at testing grounds of hard domestic garbage in power supply system in the Republic of Belarus. An example of optimization using mathematical modeling of plant operation which is used for bio-gas enrichment is given in the paper.

 

An investigation has been carried out and an approximate solution in the form of an iteration sequence of one singular integro-differential equation with an integral, which is understood as a main value by Cauchy, and also one integral equation with logarithmic core is given in the paper.

 

Investigation of mathematical models and problems of optimum industrial process has been carried out with the help of operational calculus theory, impulse function theory, set theory, time-tables, combinatory optimization. Analytical expressions describing discontinuous industrial process have been obtained and their geometrical interpretation is also given in the paper.

Myth is considered as the first historical form of human outlook. It is immanently inherent in human’s nature and has timeless character. Myth realizes an integral world outlook combining reality and fantasy, natural and super-natural, knowledge and faith. Myths exert a significant effect on consciousness and behaviour of people.

Formation of science as a social institute is considered as a very important component in the dynamics of public life. Science development reflects general tendencies of technical progress in their historical prospects. Study of main stages of science history acquires a great significance within the context of techno-genesis processes under modern conditions.

There are definite criteria that help to classify individual entrepreneurs and organizations as small and medium business categories. Definition of an economic management subject as a small enterprise and an individual entrepreneur provides possibilities to obtain tax privileges and other preferences in some countries.

The paper considers peculiar features of criteria that allow to define an economic management subject as a small and medium business in Belarus, Russia and Poland. Comparison has been carried out according to such criteria as average manpower, type of economic activity, annual turnover, purpose of the activity and founder staff.

The comparative analysis has made it possible to reveal similar features and significant differences between criteria used for definition of small entrepreneurship in the above-mentioned countries. Corresponding conclusions in respect of Belarus are made in the paper. The paper also contains evaluation of application of some criteria in our country.

Insurance market plays an important role in the economic development and has a special significance in the countries with economy of the transition period. In spite of its positive influence exerted on the development of national economy the level of  insurance service spreading is still rather low.  The paper considers main results of the activity of the Belarusian insurance organizations. Usage of statistic evaluation methods makes it possible to break them in separate groups. The conducted analysis of organizations’ financial flows (receipts, payments and profits) for the period of 2005–2007 testifies to their dynamic development. Economic management subjects of non-state ownership take leading positions in this matter.

Further growth of commercial insurance market greatly depends on the government efficiency to regulate the given sphere of activity. Removal of existing negative factors including creation of equal competitive conditions for all participants of the market, its demonopolization, will favor its development. 

The paper presents ranking of scientific thought used for solution of economic security problems according to periods. Definition of enterprise economic security system is given in the paper. The paper reveals its structure, a mechanism of interaction and tasks of its functioning. Definition of enterprise economic security is introduced in the paper.

The paper considers problems on state interference in economic life of the society under conditions of market economy. Main approaches in the evolution process of  theoretical views in respect of state market regulation, namely: classical, cainsiansky and liberal are analyzed in the paper.