The paper contains investigation results and proposes a method for calculation of optimum cutting rate. The method takes into account energy-consumption indices of technological equipment that permits to improve technological energy efficiency of cutting process.

The paper describes design of rolling heads used for cold rolling of straight-sided splines on shafts and presents theoretical principles of this process. These principles make it possible to calculate an effort which is required for pushing billet through rolling-on rolls with due account of metal hardening during deformation.

The paper considers some technologies pertaining to manufacturing ferromolybdenum preliminary alloy. It has been shown that the reduction melting method based on the aluminium thermal metallurgy presents practical interest for manufacturing the given alloy. Compositions of mixture for melting the preliminary alloy have been determined on the basis of thermodynamic reactions running during the reduction.

It has been established that metallurgical preliminary alloy output depends on intensity of reaction mode and the output is equal to 97 % for optimal conditions with molybdenum content of  about 51 %. Industrial tests have proved effectiveness of the developed technology for  obtaining  ferromolybdenum which is used for subsequent alloying of low alloy steels.

The paper describes creation technology of composite material on the basis of oxide ceramics with inclusion of solid lubricant for gas-thermal spraying of wear resistant coatingss described.

Development of microelectronics requires solution of the problem ensuring unity of linear measurements in a submicron range. The problem can be solved on the condition that calibration of measuring devices shall be made in accordance with reference samples that is a short length scale.

While making calibration of measuring equipment with the help of a reference measure it is important to investigate components of the method accuracy and their influence on measuring results. The paper considers methodical errors which are specific for methods of optical and atomic force microscopy. Calibration results of an optical measuring microscope are given in the paper. The paper reveals that an additive error depends on parameters of a material and the form of measured elements for an optical measuring microscope. The methodical error of atomic force microscopes is predicated on the probe point shape. The paper considers a short length scale used for calibration of optical and atomic force microscopes. Recommendations for users of the measuring equipment are formulated in the paper.

The paper considers experimental measurements which are taken with the help of highly-accurate electronic tachometer in order to develop methodology for controlling verticality of  building and structure walls. All calculations and plottings have been made automatically in the LISCAD program complex. At the same time it has been proposed that interpretation of measuring results is to be made in accordance with digital models, vertical profiles and layouts of walls shown by iso-lines.

The paper reveals a brand-new direction in simulation of frame and continual structures while calculating static and dynamic loads and stability.  An electronic model has been synthesized  for an investigated object and then it has been analyzed not with the help of  specialized analog computing techniques but by means of high-performance software package for electronic circuit calculation using a personal computer.

The given paper contains exact algebraic equations corresponding to differential equations for lateral bending calculation of frame structures without and with due account of viscoelastic material properties in compliance with the Kelvin model.

The exact algebraic equation for a beam on elastic supports (or elastic Winkler foundation) has been derived for quartic differential equation.

The paper presents a number of exact algebraic equations which are equivalent to differential equations for transverse-longitudinal bending calculation of frame structures without and with due account of viscoelastic material properties when lateral and longitudinal loads are applied in the form of  impulses with any periods of their duration and any interchangeability.

 

An analysis of statistical data has shown that about 60 % of all types of road surface destructions and damages in the Republic of Belarus are attributed to cracks (separate, frequent and cracks network). The process of cracks formation in the asphalt concrete pavement is rather complicated and it is affected by a number of factors. The most important and determining factors are character and value of traffic loads, temperature action, road pavement structure, properties of materials used for its layers. Some regularities of the cracks formation and development in the asphalt-concrete layers of the pavement have been established on the basis of the physical and mathematical modeling. Application of a finite  element  method for  calculations  has made it possible to determine  numerical values of compressive and tensile stresses arising due to temperature action and traffic load, deflection of road pavement constructive layers. The paper contains recommendations for a road pavement design and repair of asphalt-concrete pavements which have been made on the basis of the obtained data analysis.

Experimental research results of the stress intensity factor at normal separation, К_IC, and cross-section shift, K_IIC, respectively, of high-strength concrete are presented. Research on the specific power changing inputs on quasi-static destruction is carried out.

The compact structure on the basis of the Portland cement modified with carbon nanodispersed systems has been studied. Carbon nanotubes Graphistrength by «Arkema» dispersed into the hydrodynamic plant in the solution of surface-active agent (SAA) Polyplast SP-1 are used as modifying additives. An increase of the cross-breaking strength of a fine grain concrete up to 45,1 % and of the compressing strength up to 96,8 % was observed. The increase of concrete strength is related to morphological changes of new crystalline hydrate formations providing a less defective structure of cement matrix with high density.

 

The paper provides investigation results pertaining to development of methodology for forecasting traffic accidents using a “conflict zone” method that considers potential danger for two typical urban areas, namely: signaled crossings and bumps that are made in the areas of zebra crossings and it also considers various types and kinds of conflicts. The investigations have made it possible to obtain various indices of threshold sensitivity in respect of  potential risks  and in relation to traffic conflict. The developed methodology for traffic accident forecasting permits to introduce a “conflict zone” method in traffic management.

 

The paper describes a mathematical model for planetary double-row in-wheel motor gear box. Main parameters of its dynamic system have been determined in the paper. The paper reveals simulation of transition processes during starting and acceleration of a mine truck with electric motor wheels. Its own gear box frequency has been established theoretically and experimentally in the paper. The paper proposes an algorithm and program for calculations as an alternative to high-cost tests while investigating gear mechanism dynamics of large-size planetary gearboxes.

 In order to increase technical perfection of line protection it looks advantageous to use reliable data on short circuit occurrence. Realization of the function on detection of faults in microprocessor-based  over-current  protection of one-side  supply  lines  makes it possible  significantly to expand the zone of immediate switching-off of short circuit. The paper considers distance principle which is applied for measuring components of complex resistance of the damaged loop while using an algorithm of orthogonal components. Expressions for determination of distance up to the damage location have been proposed with due account of short circuit type. An optimum algorithm characterized by high accuracy and good dynamic properties has been selected on the basis of investigations executed with the help of numerical experimental method  when the line is operating in the mode of maximum load and idle running for various types of damages and  with the presence of a transient resistance.

 

The paper shows main approaches accepted for formation of database on reliability of heat-power equipment applied at thermal power stations. The used methods of probability theory and up-to-date computer technologies have made it possible to develop software required for database formation and which is operating in dialogue format. The database users can determine the most fragile units parts of boilers and turbines during the operational process, indices of their operation and apply these factors in their practical activity.

The paper contains a classification of internal and external threats for thermal power plants and recommendations on minimization of these risks. A set of concrete measures aimed at ensuring TPP energy security has been presented in the paper. The system comprises preventive measures aimed at reducing the possibilities of emergence and implementation of internal and external threats. The system also presupposes to decrease susceptibility of fuel- and energy supply systems to the threats, and application of liquidation measures that ensure elimination of emergency situation consequences and restoration of the conditions concerning fuel- and power supply to consumers.