The paper contains investigations on element vibration of a real residential 9-storeyed reinforced-concrete frame building induced by train movement in the shallow subway. A design model for a problem on propagation of bending waves within the limits of the typical fragment of a skeleton is presented in the paper. The steady state vibrations of a column and reinforced-concrete slab induced by an excited force which is equivalent to the impact of the subway trains have been investigated in the paper. The problem has been solved numerically on the basis of the ANSYS FEA program. Numerical results have been compared with an approximate analytical solution and data on full-scale experiment. A prediction technique for vibration propagation in the designed buildings is offered in the paper.

 

The paper reveals methods for investigation of materials and, particularly, determination of reinforcement strength grade while exploring structures of buildings and facilities in respect of their applicability in the future.

 

The paper considers problems pertaining to designing of accessories for metal-cutting machine tools. The approach based on expert systems technologies has been used in the paper. The paper describes a hybrid expert system and its knowledge is presented in the form of production rules. The paper studies knowledge bases intended for a selection of basing scheme and also for a selection of clamping elements and power drives of machine-tool accessories. Variable conditions of database rules are described in the paper. The paper presents an example of selecting a structure of a power mechanism for a machine tool accessory. The possibility to use an expert system in the integrated systems of automated machine-tool accessory designing is revealed  in the paper.

 

Formation processes, tribotechnical and wear-resistant properties of composite gas thermal coatings being dispersively strengthened by synthetic diamonds and electro-corundum are investigated in the paper.

The paper contains description about obtaining two-phase boride coatings on preliminary cemented steel-20. Being subsequently thermally treated surface hardness of the hardened steel has become equal to 66-68 HRC.

Regression dependencies are derived for determination of equipment usage rate in machining areas and lines on the results of the simulation modeling. The peculiar features of the dependencies are versatility and broad incidence of factors. Determination accuracy of an average equipment usage rate value is equal to 0.035 with confidential probability of 0.95.

The paper considers a method and an instrument for measuring amplitudes and  periods of physical pendulum oscillations with rolling-contact bearing in the regime of micro-swings when the oscillation amplitude is significantly less of an elastic contact angle. It has been established that the main factors limiting a measuring accuracy are noises of the measuring circuit, base vibration and analog-digital conversion. A new measuring methodology based on original algorithms of data processing and application of the well-known methods for statistic processing of a measuring signal is  proposed in the paper. The paper contains error estimations for measuring oscillation amplitudes justified by discreteness of a signal conversion in a photoelectric receptor and also by the influence of measuring circuit noise. The paper reveals that the applied methodologies make it possible to ensure measuring of amplitudes with an error of 0.2 second of arc and measuring of a period with an error of 10^–4 s. The original measuring instrument including mechanical and optical devices and also an electric circuit of optical-to-electrical measuring signal conversion is described in the paper.

 

The paper contains an analysis of specific features pertaining to the activity of operators dealing with automatic control systems of gas-distribution stations. The professional operator’s activity is presented in the form of the developed data model. Possible conceptual approaches to the research are analyzed in the paper. The paper describes an author’s approach to studying a risk decrease problem in the activity of operators on the basis of the analytical research results. Technology for obtaining  research results is cited in the paper.

 

The paper presents results of research on planning, organizational characteristics and regulation modes at  the regulated pedestrian crossings, located out of crossroads in the street and road network of Minsk. Some regularities pertaining to the influence of the investigated characteristics on road traffic safety of pedestrians are revealed in the paper. Practical offers on increase of road traffic safety of pedestrians in the Republic of Belarus have been developed on the basis of the executed investigations and cited in the paper.

 

The paper considers a role of technical diagnostics in the process of machine operation.

An intellectual sensor module of soil light-color control designed for an accurate agriculture technology which comprises functions of self-diagnostics, self-corrections and self-attestation. Circuit diagrams sensor module components have been developed on the basis of a micro-controller, a photo-diode driver, an interface integrated circuit and a receiving block of optical pulses. An algorithm and an operational program of a microcontroller have been devised for executing control over light pulses, processing of  photoelectric receptor signals, data receive-transmit operations, correction of sensitive elements, diagnostics of system failure and attestation of control results.

A new information technology for automation of state ecological project expertise  has been developed in the process of research. The technology is intended for specialists of Ministry of Natural Resources and Environmental Protection of the Republic of Belarus. The paper contains description of the gridding to the GIS electronic maps of situation plans concerning location of facilities used for economic activities and diagrams of environment contamination sources, information technology for an analysis of calculation results in respect of dispersion of pollutant emissions, functions pertaining to reflection of  calculation results on electronic topographic map.

The paper present results concerning determination of quantitative composition of soap stock while using methods for centrifugal concentration and fractional separation. Gas chromatography analysis data on soap stock are obtained in the paper. An isolation of higher fatty acids have been executed and their sodium, potassium and zinc salts have been obtained in the research. Dependence of the surface tension of potassium soap water solutions on concentration has been studied and potassium soap surface activity has been determined in the paper.

The paper considers a decrease in consumption of natural gas by means of  stabilization of the GTU power characteristics in summer when their degradation is observed due to higher ambient temperature and also the possibility to use an excess of thermal energy which occurs in a non-heating period for preservation of the GTU power and efficiency that provides sufficient economy of the initial fuel.

Analysis of the published papers written by national and foreign researchers reveals that an increasing global energy deficit, exhaustion of  fossil organic and nuclear fuels, chemical and radio-active contamination of the environment are main reasons in favour of  thorough investigation  and wide introduction of non-conventional and renewable energy sources. Nowadays Vietnamese Institute of Energy Science has been developing the state-of-the-art bio-gas technologies on the  basis of application and modernization of Chinese and Dutch family-style technologies. The most rational technologies are combined ones which operate using various types of energy raw materials, for example, solar and bio-gas energy because usage of solar energy expands operational possibilities of the bio-gas system, ensures its operation within wide temperature range creating necessary parameters for the required technological task.

The paper considers specific features of a stress-strain state of structure elements which have cylindrical form and which are subjected to the high temperature field, neutron irradiation. An analytical solution concerning displacement and stress dependences on a cylinder radius has been obtained and curve dependences have been constructed in the paper..

Terminology of  such concepts as «competitiveness» and «competitive price» is specified and capacity of a potential market segment for positioning innovative production is estimated in the paper. The paper analyzes a method for estimation of a quality rate on the basis of product consumer attractiveness. An improved  methodology for forecasting of a competitive price has been put on an evaluation test  while using actual data.  

A wholesale trade can be implemented in various organizational forms and a cash and carry warehouse is considered as one of the most perspective and least developed forms in the Republic of Belarus. The paper analyzes tendencies of a cash and carry  warehouse  development  in the Republic of Belarus. Main problems and appropriate  measures for their solution are cited in the paper.

 

The paper describes a visit of the BNTU students and lecturers to the Lublin University of Technology for informative and practical training.