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The paper analyzes selection of oxides and describes in details a majority of oxide systems which are applicable for stabilization of zirconium dioxide while obtaining thermal barrier coatings with maximum amount of tetragonal phase. Methodology of investigation is based on a review of analytical information on the current state of thermal barrier coatings on the basis of zirconium dioxide stabilized by oxides of rare-earth metals. The method used for application of zirconium dioxide thermal barrier coatings is plasma spraying. Positive results have been also obtained while applying e-beam sputtering, ion-plasma deposition and magnetron sputtering. Nevertheless preferred plasma spraying application for thermal barrier coatings still continues due to its high productivity and versatility that permits to deposit metallic and ceramic materials of the ordered chemical and phase composition.Ytterbium and cerium oxides have been selected as oxides for stabilization of zirconium dioxide in order to obtain thermal barrier coatings. The paper also considers аn oxide system of zirconium dioxide: “hafnium oxide – yttrium oxide”, representing in itself the structure which is similar to zirconium dioxide.

A finite elements method (FEM)-analysis has been carried out with the purpose to study dynamics of carrying system in a machine tool of unique height. This is a one-off machine with high traveling column and a support with horizontal slide can move vertically along the column. Spindle milling and boring units are mounted telescopically at slide butt end. The FEM-analysis of the machine tool has been made due to its renovation. Machine resonances, responses to cutting force, static and dynamic rigidity in spindles have been estimated in the paper. The machine carrying system is subtle, heavy and structurally complicated. Its structural chain includes a carriage, a column, a support, a slide, spindle units interconnected with the help of hydro-static guides. While varying main parameters their influence on rigidity has been investigated in the paper. Height of support lifting, column material and rigidity of longitudinal drive have been changed during the investigations.Static, modal and harmonic MEF-analyses have been executed in the paper. Frequency-response characteristic of the machine has been constructed in the process of the investigations. Two support bending resonances have been detected in the column at low frequency. Such Due to this there are limits for usage of the machine in sub-resonance and static frequency range. The most powerful resonance has been observed at frequency of 27.8 Hz. The resonance has manifested itself as torsional oscillations of the column together with the support and the slide.Slide bending resonances have been revealed at higher frequencies 65–105 Hz. Three intervals which are fit for machine operation have been determined between resonance ranges. There is a prospective usage of the machine in inter-resonance (32–65 Hz) and super-resonance (more than 105 Hz) intervals. It has been shown that rigidity in spindle is a sequence higher in dynamic intervals than in a static interval. Machine subtility can be compensated by its transition to high-speed machining.

The purpose of this paper is to determine dependence between heat generation and resistance to deformation of structural steel.It has been assumed on the basis of the represented data that in the course of deformation of structural steel physicochemical interactions of dislocations and impurity atoms occurring in the slip bands result in heat generation and temperature increase of product surface. Interdependence of heat generation and elastic-plastic deformation has been experimentally proved by set of experiments on low-carbon steel plate extension. In the case of deformation its intensity and rate are considered as main factors that determine local material heating in the pre-fracture nucleus and temperature directly exerts its influence on diffusion processes and changes in physical and mechanical characteristics of the material in the pre-fracture nucleus. The obtained average heating temperature for the pre-fracture nucleus is equal approximately (20–90)°С for low-carbon steel ВСт3сп while using quasi-static extension. The paper presents data pertaining to steel plate deformation that point to the fact that elastic-plastic deformation is accompanied by deformation heat generation and a crack initiation is caused by thermo mechanical process. Heat is formed in the slip bands and their direction corresponds to the maximum shearing stresses. Surface temperature in the zone of crack initiation has reached 88 °С in the pre-fracture stage. The Davidenkov-Spiridonova formula has been derived while using a concept of "surface energy" and Laplace's formula. This formula makes it possible to determine resistance to deformation of a stretched round steel rod in the stage of neck formation. The paper shows formula’s dependence on the deformation heat generation.

The proposed paper is a continuation of the work, published in the previous issue. It is destined for specialists who are engaged in solution of problems pertaining to efficiency of light industry in Belarus which is considered as one of the branches being significantly involved in formation of national economy, its export potential and social climate. It is extremely relevant to reduce production costs in order to preserve and add strength to the branch positions in the markets. Production of natural, synthetic and knitted materials and their subsequent treatment are unreasonably power-consuming processes. Fundamental solution of the problem for reduction of production costs is to decrease its energy component and this can be achieved due to transition to modern heat and power systems in technological complexes of enterprises.The first part of the paper has considered a range of issues that served as a basis for obtaining statistical models in order to forecast the required production volume of main knitted and textile materials. Forecasting has been prepared for a period of more than 20 years because it has been predetermined by development horizon of comprehensive modernization of energy supply systems at enterprises of light industry. The production volumes essentially differ from those that have been stipulated in the programs of light industry.The present paper shows selection of statistical game-type for determination of build-up rate of the production volume for every textile enterprise. The so-called “Game with Nature” has been selected as a game which is widely used for solution of analogous demand problems. The statistical forecasting models of production obtained in the first part are applied in the second part of the paper which considers strategies for development of individual enterprises. JSC :Baranovichi Industrial Cotton Association” has been taken an example in the paper. Production volumes of any enterprise are determined on the basis of the development strategies with due account of risk minimization and obtaining maximum average expected profit. The average expected production of the enterprise is determined from these strategies in the light of minimizing risks and maximizing profits. Fundamental capacity of power consumption for designing their own cogeneration plants can be determined while using the concept of intensive energy saving. The concept prescribes implementation of a systematic approach that takes into account the necessity of maximum utilization of secondary low-temperature production flows, specificity in consumption and generation schedules of energy flows, conditions of an industrial unit that includes the enterprise, requirements of the power system of Belarus under conditions of NPP operation.основе концепции интенсивного энергосбережения можно установить базовую мощность энергопотребления для проектирования собственных когенерационных установок. Концепция предписывает реализацию системного подхода, учитывающего необходимость максимальной утилизации побочных низкотемпературных потоков производства, специфику графиков потребления и генерации энергопотоков, условия промышленного узла, в который входит предприятие, и требования энергосистемы Беларуси в условиях работы АЭС.

The paper considers problems that permit to solve such issue as organization of transport service for suburban population with due account of passenger transport fatigue which is considered as one of subconscious criteria for selection of a travel mode. Improvement of transportation process entails an increase in demand for such service. Demands predetermine transport supply and situation on the market depends on supply-and-demand balance. The paper presents an analysis of approaches to the estimation of parameters for a suburban transport system with due regard for influence of transport process parameters on the rate of passenger transport fatigue. This rate is estimated through value of an index which demonstrates an activity of passenger’s regulatory systems while performing every element of motion process. Nonlinear regression equation has been used to describe changes in the activity index of the passenger’s regulatory systems when a passenger is taking a standing position in a passenger compartment of a suburban transport facility. In this case value of activity index of regulatory systems before transportation, passenger age, transportation duration, operation factor of transport capacity and ratio of new bus cost to nominal capacity have been taken as variables for calculations.The paper proposes an index change model for assessment of passenger’s transport fatigue when a passenger has a standing position in a transport facility. The model has shown that an impact of the activity index of passenger’s regulatory systems before making any elemental motion is rather pertinent because this index provides information on an initial condition of a person before executing any other elemental motion. The influence of the activity index of passenger’s regulatory systems before making any elemental motion is considered as an important characteristic because it has an impact on passenger’s condition after executing previous elemental motions. Effects of age on organism adaptive properties are negative. Transport duration has also negative effect on the activity index of regulatory systems. It has been determined that a higher level of transport facility ergonomics helps to reduce fatigue during the travel.

The paper describes a conception of intelligent transport systems and reveals their benefit in solution of various tasks: road traffic safety, speed increase, ecology improvement, relief of urban territories, comfort improvement and others. The intelligent transport systems cover all types of transport and consider all the elements of transportation system: transport facilities, infrastructure, dynamically interаctive drivers or users. The information is considered as a basis of the intelligent transport systems, whether we have statistic or operational transportation data or a digital map. Data obtained with the help of such systems can provide real-time information on current situation in the network or on-line information in order to plan a road trip. In addition to the mentioned capabilities of the intelligent transport systems in respect of solution of modern transport problems the paper considers comfort factors and also their technologies, logical and physical architecture, productivity and operational efficiency.The paper provides an analysis on the development of the intelligent transport systems in the world: the USA, European Union and Russia. The initial stage for creation of the intelligent transport systems has been characterized with due account of the experience of various countries. The paper describes myths and realities pertaining to formation of such systems in the countries with transition economy. Peculiar features concerning development of the intelligent transport systems in Belarus have been analyzed in the paper. The paper presents recommendations on practical steps for establishing the Belarusian intelligent transport system. The main problem in creation of the intelligent transport systems is not technical issue but an institutional one. It is necessary to combine efforts of state, research, industrial, commercial, academic structures in the united team.

The paper considers a synthesis problem for automatic control systems, which operate in various modes, for example, tracking step-wise effects and slowly changing input signals. Generally, one controller cannot ensure the required qualitative characteristics in all operational modes. One of the methods to solve this problem is to create a reconfigurable control system. The authors propose a reconfigurable control system with two discrete-time controllers. The first one is placed in series with the forward path and the second one is connected in parallel with the reverse path having additional gain and unity feedback. Such system structure is characterized by its simplicity and qualitative operational ability to track step-wise and sinusoidal inputs with different amplitudes.The paper presents a developed block diagram of the reconfigurable system and describes its operational principle. Three various plants have been chosen with the purpose to check the operation of the system. Digital controllers have been selected and their parameters have been determined in accordance with the requirements to qualitative operational characteristics of the system. Mathematical modeling has been executed in order to check the operation of the proposed system with various plants and digital controllers. The modeling confirms good –speed performance of the automatic control system while tracking stepwise signals, provision of minimum dynamic error for the given controllers and time delay while tracking harmonic signals with various amplitudes. The obtained results have been successfully tested and can be used for development of automatic control systems that contain other plants and digital controllers, if there are various and occasionally contradictory requirements to their operational quality.

The existing methods for auto-technical expertise presuppose selection of some parameters on the basis of the expert’s intuition and experience. Type of a vehicle and its loading rate, road conditions are not taken into account also in the case when deceleration is to be determined. While carrying out the analysis it has been established that an application of special software makes it possible to improve significantly efficiency of the executed works directed on solution of the assigned tasks, to speed up calculation processes, to decrease qualitatively probability of arithmetic errors and provides the possibility to visualize results of the conducted investigations. Possibility of using various models for dynamic motion simulation and collision of vehicles (in the form of 3D-models) has been established in the paper. In such a case specific features of vehicle technical conditions, its loading rate and condition of roadway surface have been taken account in the paper. The given paper also permits to obtain a dynamic display of reconstructed accident mechanism in axonometric projection, to film video-clips when a camera is positioned at any spatial point: road, roadside, raised position, moving vehicle, driver's seat in the vehicle.The paper contains an analysis of possibilities of road traffic accident simulation programs, a statistical analysis that shows significance in differences between simulation results when various programs have been used. The paper presents initial data and results of vehicle speed calculation on the basis of braking track length which have been obtained with the help of road traffic accident express analysis (a classical approach) and PC-Crash when additional influencing factors are taken into account. A number of shortcomings have been revealed while analyzing the simulation results of the applied software. The shortcomings must be removed in the analyzed software products.On the basis of the executed analysis in respect of application of road traffic accident simulation programs it has been proposed to involve responsible and controlling authorities (State Automobile Inspectorate, expert institutions, insurance companies) for practical activity with the purpose to increase the objectivity of the result conclusions.

Problems arise in the process of designing, production and investigation of a complicated technological machine. These problems concern not only properties of some types of equipment but they have respect to regularities of control object functioning as a whole. A technological machine is thought of as such technological complex where it is possible to lay emphasis on a control system (or controlling device) and a controlled object. The paper analyzes a number of existing approaches to construction of models for controlling devices and their functioning. A complex model for a technological machine operation has been proposed in the paper; in other words it means functioning of a controlling device and a controlled object of the technological machine. In this case models of the controlling device and the controlled object of the technological machine can be represented as aggregate combination (elements) of these models. The paper describes a conception on realization of a complex model for a technological machine as a model for interaction of units (elements) in the controlling device and the controlled object. When a control activation is given to the controlling device of the technological machine its modelling is executed at an algorithmic or logic level and the obtained output signals are interpreted as events and information about them is transferred to executive mechanisms.The proposed scheme of aggregate integration considers element models as object classes and the integration scheme is presented as a combination of object property values (combination of a great many input and output contacts) and combination of object interactions (in the form of an integration operator). Spawn of parent object descendants of the technological machine model and creation of their copies in various project parts is one of the most important means of the distributed technological machine modelling that makes it possible to develop complicated models of technical devices still at the project stage.

The essence of a competition as an objective law for development of the commodities production based on private ownership of the means of production and commodity exchange has been revealed in the paper. The paper presents an economic basis of market economy (private ownership) which generates a corresponding production objective. Such purpose is a maximization of profit and a minimization of market subject expenses. Therefore, a struggle for the most favourable conditions on commodity production and sales is inevitable in such situation. The struggle is considered in the community with developed market economy as a competition.The competition is regarded not as an exogenic factor exerting its influence on market economic system from the outside, but as an objective phenomenon which is inherent to management market system in itself. Such treatment is substantiated by economic disintegration of individual commodity producers. Being an important engine of market economy, the competition does not establish its laws, and its role is to be an executive of data which are internally inherent in commodity production laws and firstly it concerns a profit maximization law which defines a purpose and guiding motif of economic entities in the given economy.The competition plays a contradictory role under conditions of market economy. On the one hand, it makes manufacturers constantly to aspire to expense reduction for the sake of profit increase. This has resulted in labour productivity increase, production cost decrease and a company receives an opportunity to reduce retail price for its products. Consequently, the competition acts as a potential factor for lowering of prices while increasing production efficiency. On the other hand, sellers have more freedom in price fixing under conditions of imperfect competition as they sell their products under the conditions of a monopolistic competition or an oligopoly. This is the main weakest point of the market economy system.

The paper proposes a structure of precision motion system built on the basis of a circular multi-coordinate synchronous segment motor and reconfigurable parallel kinematic mechanism. The multi-coordinate synchronous segment motor may have from two to six movable segments depending on the design, and number of the segments generally defines an internal mobility of the motor. A specific feature of the parallel kinematic mechanism consists in the possibility of its structure reconfiguration by serial connection of two neighboring rods with the help of free elements of their spherical joints into triangular circuits with one spherical hinge at the common vertex. As result of this, the controlled motion of motor movable segments is transformed into the complex spatial displacement of circular platform with number of degrees of freedom up to six inclusively.A mathematical model for solution of the kinematic problem in the investigated parallel mechanism has been offered in the paper. The model allows to calculate a position of movable segments of multi-coordinate synchronous motor depending on the desired position and orientation of the executive circular platform. The parametric definition of base point positions in the motor segments in time allows eventually to form algorithms of programmable motions.The paper substantiates ability to embed the developed motion system into projection unit of opto-mechanical equipment while preserving traditional configuration scheme. This provides the possibility of adaptive adjustment of optical elements during operation; it allows to adjust the optical elements when the geometry of projection system is changed due to deterioration. As result, main characteristics of projection system: resolution, depth of field and image contrast and distortion are maintained at the required level. The developed motion system can be used as a coordinate system of positioning, alignment and scanning in the assembly and other precision equipment.

Devices of infrared equipment are often operating under complicated environmental conditions. First of all it concerns temperature range which can reach ±60 °С in accordance with the requirements. Proceeding from this condition one of the most important tasks for designing objectives if the infrared devices is to preserve their main characteristics during temperature fluctuations. Temperature changes in internal part of the objective leads to changes in design values of the optical system and it leads consequently to thermal defocusing and appearance of aberrations in image that entails sharp decrease in frequency and energy characteristics of the system. The paper considers a problem on compensation of temperature field influence on image quality of focusing units operating in infrared spectral range when there is uniform temperature distribution in the system.It is expedient to remove dependences of infrared objective characteristics on temperature at the designing stage of focusing unit while using an athermalization method. The paper examines application results of the developed methodology for passive optical athermalization for designing infrared triplet objectives and reveals their advantages in comparison with non-athermalized analogues. Schemes of thermal-independent three-component objectives operating in in the long-distance infrared range of the spectrum 8–14 mkm with matrix photo-receivers have been proposed in the paper. The paper provides results of the analysis on influence of temperature field changes on image quality as non-athermalized so athermalized infrared objectives as well. Combinations of optical materials and characteristics of optical systems for creation of athermalized objectives with long-distance infrared spectrum range have been recommended in the paper. The paper presents an optical system of the triplet which is calculated on the basis of the developed athermalization methodology.

The paper presents an interest for those specialists who are involved in solution of efficiency problems in light industry of Belarus as one of the significant industries that forms an economic situation in the Republic, its export potential and social climate. It is extremely relevant for the Belarusian enterprises to reduce production costs in order to preserve and strengthen positions in the light industry market. Operating capacities for production of natural, synthetic textile and knit-wear materials and their subsequent treatment are in many respects unjustifiably energy intensive. Nowadays the only acceptable solution of the problem for reduction of production costs is to decrease its energy component. Such approach requires transition to creation of modern heat and power supply systems at heat technology enterprises.The most important sub-system of the enterprises is own combined production of energy flows of secondary electrical and heat energy, freeze. There is a complex of problems that arise during designing process of tri-generation unit. One of the most important problems presupposes determination of a base load demand and capacity of every energy flow generated by an energy source. The solution is directly related to production output, which in its turn is determined by the requirements of sales markets. Due to various reasons the markets have their own specificity for the enterprises under consideration. It is proposed to use statistical methods for searching requirements. In this connection it is necessary to take into account industry development rate (pre-determined by State Programs, Plans, Governmental solutions, including directive instructions), production volumes of competitive goods and actual goods situation on the sales market.The paper presents the first part of the executed complex investigations which are directed on the development of scientifically-substantiated proposals for higher energy efficiency of the industry as a whole. It has become possible on the basis of the results obtained in the process of studying its power and heat engineering problems. The results of an analytical calculation analysis of statistical and obtained forecasting data are considered as a basis for the development of scientifically substantiated proposals for modernization of energy supply systems and power resource saving of the industry that fully corresponds to the investigation objective. The result of the executed investigations, that is a significant reduction of the energy component in the production costs will be presented in the follow-up publications.

Basic requirements to sensor and controlling tracts of mechatronic systems with the remote organization of object control processes have been considered in the paper. A rational approach presupposes designing of the mentioned systems as multichannel technical complexes intended for parallel or quasi-parallel force-moment control of outlet mechanical links (motion modules) by multiple coordinates of the required phase space. It has been shown that the use of digitizing principles and distributed data procession in mechatronic systems makes it possible to pass to the unified structure and typical set of software and hardware functions of the aforesaid tracts. The paper gives consideration to a structural and functional scheme of the mechatronic system which contains an intellectual sensor device, a controlling center and an intellectual executive mechanism. The tasks that are linked with organization of preliminary information procession and construction of the systematic interface for transfer of telemetric transactions between controlled objects and the control center have been specified in the paper. Solution of a functionally full set of logically completed tasks is imposed to software and hardware tracts of the mechatronic system which is based on the abovementioned principles.The paper presents preliminary distribution of functions according to the system resources that is between an intellectual sensor unit, a control center and an intellectual executive mechanism. One of the most important features is an informational compatibility of the system components which is achieved owing to the use of unified transactions. The noise immune data coding expands useful informational transaction volume to some actual volume. It has been shown that construction of tract transfer and transaction reception in the intellectual mechatronic system on the basis of radio channels is considered as the most complicated technical solution.

Nowadays the work is in progress to develop wheeled and caterpillar tractors with electromechanical transmission. Range of changes in transmission gear ratio while using propulsion electric motor depends on mechanical characteristics of a tractor propulsion electric motor which is equipped with electromechanical transmission. In case when the range is rather high then it is possible to minimize number of gearings in the tractor gearing box or exclude its usage at all. Type of the applied propulsion electric motor and regulation method specify type of mechanical characteristics (characteristics family) of the propulsion electric motor.The paper considers a propulsion asynchronous electric motor with frequency control. While using frequency control it is possible to regulate electric motor revolutions by mutual changes in voltage and voltage frequency. There are various laws of mutual changes in voltage and frequency (regulation laws). Selection of a regulation law influences on type of mechanical characteristics of a propulsion electric motor. Application of any law can be admissible only for some specific range of voltage frequency otherwise it is possible to exceed some parameters (for example, admissible voltage in the winding of electric motor stator). It is necessary to ensure the required moment within wide range for a tractor propulsion electric motor. In this case losses in the electric motor must be minimal. Losses in the rotor of the propulsion asynchronous electric motor are directly proportional to its sliding and its best propulsion and mechanical properties of a mobile machine will be ensured in the case when sliding is preserved at a constant value. According to these reasons selection of regulation laws has been carried out for operation of the propulsion asynchronous electric motor with nominal sliding and mechanical characteristics at nominal sliding is conventionally called a nominal characteristics.The paper analyzes the possible laws of mutual application of voltage and voltage frequency and their application boundaries. A combination of laws for regulation of the propulsion asynchronous electric motor has been selected in the paper. The combination ensures the widest operational range of the electric motor with high moment value at nominal sliding and due account of limitations on application of every used regulation law. The following mechanical characteristics family has been constructed for the propulsion asynchronous electric motor regulated in accordance with the proposed law: at nominal sliding, at critical sliding, at changeable sliding and without changes in voltage and frequency.

The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa). The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality change on purification phases with various filtration rate have been determined in the paper.

In recent time piled foundations are extensively applied due to an increase of storeys in buildings constructed in Minsk and load increment on the soil. Preference is given to this approach even in the case when relatively firm soil occurs in the top part of the foundation bed. In this case maximum usage of the foundation bed bearing capacity and reduction of foundation cost are considered as top-priority tasks for designers. One of the ways to increase the bearing capacity of piled foundations is the necessity to take into account resistance of foundation bed soil located under raft bottom. The raft as well as a shallow foundation is capable to transfer a significant part of building load into the soil. Such approach makes it possible to reduce a number of piles in the foundation or shorten their length. Then it results in shortening of the construction period and significant reduction in zero cycle. However up to the present moment reliable calculation methods that permit to take into account soil resistance in the raft base. An analysis of previous investigations on the matter executed by various researchers and a number of field investigations have been carried out with the purpose to develop the proposed methods.The paper presents results of field investigations on foundations consisting of short stamped tapered piles which are joined together with the help of the raft fragment. Strength and deformation characteristics of the bases are increasing while making such foundations in the fill-up soil. In this case the filled-up ground layer becomes a bearing layer both for piles and rafts as well. Improvement of high-plastic clay-bearing soil properties is ensured by ramming dry concrete mix under pile foot. The paper describes an experience on application of the piled-raft foundation in complicated engineering and geological conditions while constructing the Orthodox Church in Minsk.

Methodology for determination of optimum setting parameters for technological equipment that ensure the prescribed accuracy of a work-piece at the preliminary machining stage under conditions of free rubbing has been developed in the paper. The paper describes a scheme for dividing lens surface into elementary sites. The so called reference points are accepted in the centre of the sites and ways of their friction are calculated which are directly-proportional connected with intensity of metal envelope removal under machining conditions using free rubbing method. Methodology for determination of range in length change of line mark during tool oscillatory motion has been proposed and analytical expressions for calculation of this range for every specific case have been obtained in the paper. The paper contains calculation of friction ways in reference points of lens diametrical cross-section for various combinations of such setting parameters of technological equipment to ensure simultaneous lens processing as length of mark line during tool oscillatory motion, rotation frequency of a lens and an input element in an executing mechanism of a machine tool, tool diameter and ratio of its frequency rotation to lens frequency rotation.The paper shows that if control over the shaping process is executed through regulation of rotation frequency of the lens and the input element in the machine tool executing mechanism then unacceptable accuracy of the machined surface is obtained in case of their equal values. The highest accuracy of the machined surface can be reached while regulating ratio value of tool and lens rotation in combination with the change of tool diameter. Experimental investigations on polishing of lens convex surface have been carried out and they correlate with theoretical calculations. Such method of investigations as a mathematical simulation of technological equipment operational zone for processing highly-accurate spherical surfaces under conditions of free rubbing has been used in the paper.

The paper considers a problem on introduction of a conception and regularities of “squeezing effect of a rail loaded non centrally by semi-sleepers having L-shaped cross-section” exemplified by belt-type tramway. Its advantages are ensured by doubled non centrally loaded foundations these are semi-sleepers. Semi-sleeper of L-shape cross-section is a lever of L-shape form, transforming a vertical load into horizontal ones and foundation squeezing. Properties of two semi-sleepers being doubled, orientated to each other and non centrally loaded have been used in order to create a positive effect. A horizontal force creates squeezing and it is revealed as a component of a vertical load during displacements which functionally depend on foundation squeezing. These dependences demonstrate that strength and deformation properties of earth foundation of vertical direction are used for creation of horizontal properties of sleeper vertical shoulder.The paper studies mechanics pertaining to a squeezing effect of a rail loaded by semi-sleepers having L-shaped cross-section. It has been established that the rail squeezing effect results from squeezing process executed in two mutually perpendicular directions (reduction of cross-sectional area) by load of a rail wheel with spacers if they are set inside of a sleeper-mechanism on an elastic foundation.Methodology for calculation of parameters on the rail reduction effect is considered as a tool for handling of applied problems on belt-type tramways. Results of the proposed rail reduction effect in problem statement for elastic conditions, with unchanged cross-sectional dimension of a rail line and introduction of correction ratio coefficients due to new initial load data have recommended for practical application as reliable values.The paper has revealed a proportional dependence of the rail reduction effect according to strength on the resultant value of reaction pressure, eccentricity difference of the resultant and load and inverse proportion due to distance along vertical line between reduction force vector and connection position of doubled foundations. Rail squeezing force will be increased if we reduce foundation height while having unchanged width and foundation pressure or if we increase an ordinate of the connection arrangement between them while having unchanged foundation height.

The paper considers a process of turning structural steel with asymmetric tool vibrations directed along feeding. Asymmetric vibrations characterized by asymmetry coefficient of vibration cycle, their frequency and amplitude are additionally transferred to the tool in the turning process with the purpose to crush chips. Conditions of stable chip breaking and obtaining optimum dimensions of chip elements have been determined in the paper. In order to reduce a negative impact of the vibration amplitude on a cutting process and quality of the machined surfaces machining must be carried out with its minimum value. In this case certain ratio of the tool vibration frequency to the work-piece rotation speed has been ensured in the paper. A formula has been obtained for calculation of this ratio with due account of the expected length of chip elements and coefficient of vibration cycle asymmetry.Influence of the asymmetric coefficient of the tool vibration cycle on roughness of the machined surfaces and cutting tool wear has been determined in the paper. According to the results pertaining to machining of work-pieces made of 45 and ШХ15 steel the paper presents mathematical relationships of machined surface roughness with cutting modes and asymmetry coefficient of tool vibration cycle. Tool feeding being one of the cutting modes exerts the most significant impact on the roughness value and increase of the tool feeding entails increase in roughness. Reduction in coefficient of vibration cycle asymmetry contributes to surface roughness reduction. However, the cutting tool wear occurs more intensive. Coefficient of the vibration cycle asymmetry must be increased in order to reduce wear rate. Therefore, the choice of the coefficient of the vibration cycle asymmetry is based on the parameters of surface roughness which must be obtained after machining and intensity of tool wear rate.The paper considers a process of turning structural steel with asymmetric tool vibrations directed along feeding. Asymmetric vibrations characterized by asymmetry coefficient of vibration cycle, their frequency and amplitude are additionally transferred to the tool in the turning process with the purpose to crush chips. Conditions of stable chip breaking and obtaining optimum dimensions of chip elements have been determined in the paper. In order to reduce a negative impact of the vibration amplitude on a cutting process and quality of the machined surfaces machining must be carried out with its minimum value. In this case certain ratio of the tool vibration frequency to the work-piece rotation speed has been ensured in the paper. A formula has been obtained for calculation of this ratio with due account of the expected length of chip elements and coefficient of vibration cycle asymmetry.Influence of the asymmetric coefficient of the tool vibration cycle on roughness of the machined surfaces and cutting tool wear has been determined in the paper. According to the results pertaining to machining of work-pieces made of 45 and ШХ15 steel the paper presents mathematical relationships of machined surface roughness with cutting modes and asymmetry coefficient of tool vibration cycle. Tool feeding being one of the cutting modes exerts the most significant impact on the roughness value and increase of the tool feeding entails increase in roughness. Reduction in coefficient of vibration cycle asymmetry contributes to surface roughness reduction. However, the cutting tool wear occurs more intensive. Coefficient of the vibration cycle asymmetry must be increased in order to reduce wear rate. Therefore, the choice of the coefficient of the vibration cycle asymmetry is based on the parameters of surface roughness which must be obtained after machining and intensity of tool wear rate.

The paper considers existing qualitative indices of transport services. Indices for evaluation of qualitative operation indices of transport complex have been proposed in the paper. Special attention has been devoted to interaction and coordination of various types of transport as the highest level of qualitative operation of transport complexes. Operational coordination of transport facilities is considered as introduction of modern management, information and communication systems while using satellite navigation-information systems. The paper has studied the possibility to create a modern automated management system for transport complex at the Ministry of Transport of the Russian Federation that ensures an efficient organization of standardized information exchange between transport complex participants.The paper provides efficient solutions on transport problems that lead to planned improvements of objective indices with small expenses. A special focus has been given to development of transport systems in large cities with the purpose to reveal their impact on operation of the national transport complex. The paper considers conceptual moments pertaining to designing and realization of an intellectual management system and creation of complex conditions that ensure maximally efficient transport management on city territory.The main purpose of transport infrastructure modernization in accordance with its types is to create modern efficient transport facilities and equipment for provision of technological infrastructure required for the system of objects included in the transport infrastructure. The modernization strategy must be governed by national policy in the field of any transport and in accordance with international development tendencies in transport industry and transport construction. In this respect the transport infrastructure is the very first consumer of innovative high technologies that determine scientific-andtechnological advance and competitive ability of national economy.

FEM-analysis of dynamics in the bearing system of a heavy-duty machine tool has been carried out in the paper. This is a prospective variant for a large-size multi-purpose machine tool with a horizontal sliding ram. A saddle and a ram are moving vertically along a subtle mono-column. A rigid double-column is used in the existing analog machine tool. A static, modal and harmonic analysis of the bearing system with the mono-column has been made in the paper. It has been done with the help of FEM-simulation prior to fabrication of a prototype sample. Previously conducted calculations for the analog machine tool have shown good compatibility of FEM-calculation with experiments.Six common machine tool resonances have been revealed for the bearing system. Their oscillating cutting forces are actively exciting three-four resonance modes. Ranges of a flexure-torsion resonance (20–40 Hz) and nose-diving resonances (70–90 Hz) have been determined in the paper. The paper shows that the range of multi-wave resonances starts significantly higher from 140 Hz. These resonances are interconnected with bending oscillations of the ram and bucklings of the column walls which are matched with the oscillations. The paper demonstrates stability in resonance pattern. The torsional resonance of the column on the frequency of nearly 40 Hz is considered as the more dangerous one. Spindle rigidity goes down up to 3.8 Н/μm. It is possible to observe self-stabilization of the torsional resonance. Frequency of the torsional oscillations is practically unchangeable when there is a lifting or lowering down of the saddle and the ram. It is related to the migration of dynamical axis of torsion.Frequency-response characteristics of the bearing system have been constructed for various saddle positions on the column. Three frequency intervals that make it possible to carry out machining operation have been determined in the paper. The first interval is a static one. The machine tool with a mono-column comes short of the analog machine tool in this interval. The main reason of it is low static rigidity of the subtle column. The second interval is narrow and it is located between flexure-torsion and nose-diving resonances. The third interval is considered as the most efficient one. The interval contains a section of inter-range pause between general machine tool and multi-wave resonances. In this case it is possible to observe a significant increase of the dynamic rigidity on the spindle that compensates the column subtility. High potential of the dynamic rigidity has been revealed in the direction of the ram axis (>2000 Н/μm). The paper shows liability of the machine tool to displacement crossings during oscillations. Peculiar features of this effect have been discussed in the paper. The diagram with a mono-column is recommended for practical application. The main condition is a transition to high-speed drive within the framework of concept on high-speed machining. It is necessary to ensure rigidity of the axial feed drive system.

One of the main ways to improve physical and mechanical properties of cement concrete is an introduction of ash obtained due to burning of fossil fuels into concrete mix. The concrete mixes with ash are characterized by high cohesion, less water gain and disintegration. At the same time the concrete has high strength, density, water resistance, resistance to sulfate corrosion. The aim of this paper is to explore the possibility to use peat ash and slag of peat enterprises of the Republic of Belarus in the concrete for improvement of its physical and mechanical properties and characteristics of peat ash, slag, micro-silica, cement, superplasticizing agent. Compositions and technology for preparation of concrete mixes have been developed and concrete samples have been have been fabricated and tested in the paper. It has been shown that the concrete containing ash, slag obtained due to burning of peat in the industrial installations of the Usiazhsky and Lidsky Peat Briquette Plants and also MK-85-grade micro-silica NSPKSAUsF-1-grade superplasticizing agent have concrete tensile strength within 78–134 MPa under axial compression and 53 MPa – for the control composition. This index is 1.5–2.5 times more than for the sample containing no additives.The usage of peat ash, slag together with MK-85-grade micro-silica and NSPKSAUsF-1-grade superplasticizing agent for fabrication of concrete and reinforced bridge and tunnel structures will provide the following advantages: reduction of cross-sectional area of structures while maintaining their bearing capacity due to higher value of tensile strength in case of axial compression; higher density, waterand gas tightness due to low water cement ratio; high resistance to aggressive environment due to lower content of capillary pores that ensures bridge structure longevity; achievement of environmental and social impacts.

Measures undertaken for improvement of road traffic safety presuppose clampdown on violation of road traffic regulations but no attention is paid to the fact that there is no possibility to ensure road traffic safety due to inconformity of roads to the modern safety requirements. Therefore reduction in accident rate is connected with some changes in approaches to designing, construction and maintenance of roads. Nowadays when the number of automobiles is extremely large and their number is increasing with every passing year driver’s professionalism becomes the most significant factor. In these circumstances the professionalism is demonstrated not so much while driving in bad road conditions as it was previously but the professionalism is more revealed in the case when it is necessary to drive in conditions of large workloads and high manoeuvring rate when a special important role is given to the capability to forecast a situation, in other words the capability to read the road. Moral climate on the road is no less important as well and it practically fully depends on a driver.The paper contains an analysis of the Gomel traffic police data on quantitative distribution of road traffic accidents and their victims according to the time of day and month, lighting conditions, weather conditions, age and sex factors, types of violations. Situations of traffic behavior, motivations of drivers and road users, drivers training have been shown in terms of impact on the road traffic accident risk. The paper considers a human factor which rather often causes an accident. An evaluation has been given to such factor as road speed of transport facilities which exerts a significant influence on an accident risk and its severity.

An analysis of main design parameters that determine a level of droplet formation intensity at the generating stage of plasma flow has been given in the paper. The paper considers the most widely used designs of water cooled consumable cathodes. Ti or Ti–Si and Fe–Cr alloys have been taken as a material for cathodes. The following calculated data: average ionic charge Zi for titanium plasma +1.6; for «titanium–silicon plasma» +1.2, an electronic discharge 1.6022 ⋅ 10–19 C, an ion velocity vi = 2 ⋅ 104 m/s, an effective volt energy equivalent of heat flow diverted in the cathode Uк = 12 V, temperature of erosion cathode surface Тп = 550 К; temperature of the cooled cathode surface То = 350 К have been accepted in order to determine dependence of a maximum admissible arc discharge current on cathode height. The calculations have been carried out for various values of the cathode heights hк (from 0.02 to 0.05 m). Diameter of a target cathode is equal to 0.08 m for a majority of technological plasma devices, therefore, the area of the erosion surface is S = 0.005 m2.A thickness selection for a consumable target cathode part in the vacuum arc plasma source has been justified in the paper. The thickness ensures formation of minimum drop phase in the plasma flow during arc cathode material evaporation. It has been shown that a maximum admissible current of an arc discharge is practically equal to the minimum current of stable arcing when thickness of the consumable cathode part is equal to 0.05 m. The admissible discharge current can be rather significant and ensure high productivity during coating process with formation of relatively low amount of droplet phase in the coating at small values of hк.

The paper presents results of investigations on influence of domestic complex chemical additive containing structured carbon nanomaterial and characterized by a combination effect (curing acceleration and plasticizing) on cement and cement stone properties. The purpose of the investigations, on the one hand, has been to confirm efficacy of УКД-1additive from the perspective for increasing the rate of gain, strength growth of cement concrete and additive influence on setting time with the purpose to preserve molding properties of concrete mixes in time, and on the other hand, that is to assess “mechanism” of the УКД-1 additive action in the cement concrete. The research results have revealed regularities in changes due to the additive of water requirements and time period of the cement setting. The reqularities are considered as a pre-requisite for relevant changes in molding properties of the concrete mixes. The paper also experimentally substantiates the possibility to decrease temperature of cement concrete heating with the УДК-1 additive. It has been done with the purpose to save energy resources under production conditions. In addition to this the paper proves the efficiency of the additive which is expressed in strength increase of cement stone up to 20–40 % in the rated age (28 days) that is considered as a basis for strength growth of cement concrete. The paper confirms a hypothesis on physical nature of this phenomenon because the X-ray phase analysis method has shown that there are no changes in morphology of portland cement hydration products under the action of the additive agent containing a structured carbon nanomaterial. Results of theoretical and experimental investigations on УКД-1 additive efficiency have been proved by industrial approbation while fabricating precast concrete products and construction of monolithic structures under plant industrial conditions (Minsk, SS “Stroyprogress” JSC MAPID) and on building sites (Mogilev, JSC Stroytrest No 12).

The paper presents constructional and technological features for manufacturing driven piles with variable strength of pile shaft. Economical efficiency of their production has been shown in the paper. The paper provides a pile cap design that ensures perception of hammer impacts with the help of lateral edges of the pile cap. Driven reinforced concrete piles which are manufactured from three shaft sections having various strength have been proposed in the paper. Material strength (concrete grade and diameter of bars) and length of shaft sections are given on a case by case basis in accordance with nature and rate of stresses in piles during their driving process. Manufacturing of polystrong piles provides an opportunity to select them for a particular construction site with due account of their preservation during driving process.A pile cap has been developed that as opposed to existing analogous designs makes it possible to transmit impact efforts from a hammer to the pile through lateral surface of its head part. The pile cap provides the possibility to increase an area for perception of hammer impact efforts by the pile and in doing so it is possible significantly to reduce a damage risk and destruction of pile concrete during its driving. Application of polystrong piles and their driving with the help of new pile cap are considered as a basis for defect-free and resource-saving technology for pile foundations in the construction.

The paper presents a calculation of contact tensions between conjugate surfaces in sphere globoidal rusk synchronous cardan hinge on the condition that there is power balance at the constant torque on the output shaft. The required torque effect on the intake shaft at the constant angular velocity has been calculated with the help of the Hertz’s theory of contact deformations . The maximum contact pressure has been ascertained through the torque which determines strength of the cardan hinge, its durability, wear rate in the conjugate friction pair. The paper investigates transmission dependence of the maximum torque while changing material quality and according to various typical sizes of the cardan hinge. Dependences of the calculated maximum torque value on material strength have been demonstrated graphically in the logarithmic coordinate system. A formula for maximum contact pressure value has been derived and it determines strength of the hinge mechanism, its durability and wear rate in the conjugate friction pair.The effect of geometrical relationship between a spherical cam radius and a globoidal surface radius of a hinge contact has been determined with the purpose to analyze optimal design parameters of the sphere globoidal rusk synchronous cardan hinge. It has been established that permissible torque in the hinge mechanism grows with a quadratic dependence while increasing a cam radius and the torque is proportionally growing while increasing an axis radius of globoidal rusk surface on which spherical cams are set. The maximum permissible torque value grows with a cubic dependence while using qualitative material with thermally treated surface and application of lubrication materials which tolerates significant (up to [σ] = 1000 MPa) contact loads. Two-fold increase of typical size of the sphere globoidal rusk synchronous cardan hinge leads to an 8-fold increase of the permissible transmitted torque.

The paper presents a mathematical model for electronic control system of the angular ignition timing (AIT) in the (ICE), which is running on ozonized fuel. An algorithm for ignition system control of internal combustion engine using ozonized fuel has been developed in the paper. A structure of the dynamic ignition system while using a control unit for supplying ozone into fuel with a purpose to improve automobile ecological and economical indices adapted to operational conditions. Application of the given system allows to ensure minimum reduction of operational petrol consumption and concentration of incomplete combustion products due to optimum ozone dosage into the fuel. The paper proposes a controlled automobile ignition system as a sequential scheme which has a great number of discrete inputs and outputs and many discrete internal states. The scheme establishes a functional dependence between input and output states. The paper provides an assessment of ecological indices according to massive emissions of carbon monoxide СО, hydrocarbon СпНт and nitric oxide NOx . The analysis of investigations results has been carried out in the paper.

Elastic modulus accuracy using atomic force microscopy depends significantly on processing quality of the experimental data obtained during nanoindentation. Multiply repeated calibration can lead to conservative value of the calibration factor. Such artefact is caused by probe slipping on silicon plate surface which is harder than surface of the investigated specimen and which is non-uniform in height. Elastic modulus calculated by the Hertz model depends on penetration value while processing the indentation data at small depth of the probe penetration into the specimen. A value being close to asymptotical one which is obtained at rather large object deformation is taken as a required modulus. Such deformation is not always possible in an experiment, or it is achieved with rather large (tens of percent) relative deformations that is beyond permissible region of the Hertz model application.The purpose of this paper is to demonstrate several new opportunities for nanoindentation data processing, as at the stage of obtaining or verifying a calibration factor of the atomic force microscope so while analyzing an investigated object penetration curve. The paper considers two methodologies for determination of the calibration factor on the basis of the Hertz and Johnson-Kendall-Roberts models and proposes new mechanisms for determination of elastic modulus while using method of atomic force microscopy. The possibility to calibrate atomic force microscope according to material with known mechanical properties has been shown in the paper. The paper substantiates the necessity and provides an algorithm for correction of the measured probe penetration depth with due account of adhesive forces while calculating the in the region of small specimen deformations. The proposed methods for determination of the calibration factor and asymptotic value of the elastic modulus will be useful for obtaining reproducible and more accurate results of atomic force microscopy for mechanical properties.

The paper presents optimization of processes for obtaining maximum content of tetragonal phase in the initial material and thermal barrier coatings (TBC) based on zirconium dioxide and hafnium oxide. Results of the investigations on phase composition of oxide HfO2 – ZrO2 – Y2O3 system have been given in the paper. The system represents a microstructure which is similar to zirconia dioxide and transformed for its application at 1300 °C. The paper explains a mechanism of hafnium oxide influence on formation of the given microstructure. The research methodology has been based on complex metallography, X – ray diffraction and electron microscopic investigations of structural elements of the composite plasma coating HfO2 – ZrO2 – Y2O system.In order to stabilize zirconium dioxide dopant oxide should not only have an appropriate size of metal ion, but also form a solid solution with the zirconia. This condition severely limits the number of possible stabilizers. In fact, such stabilization is possible only with the help of rare earth oxides (Y2O3, Yb2O3, CeO2, HfO2). Chemical purity of the applied materials plays a significant role for obtaining high-quality thermal barrier coatings. Hafnium oxide has been selected as powder for thermal barrier coatings instead of zirconium dioxide due to their similarities in structural modification, grating, chemical and physical properties and its high temperature structural transformations. It has been established that plasma thermal barrier HfO2 – ZrO2 – Y2O3 coatings consist of one tetragonal phase. This phase is equivalent to a non-equilibrium tetragonal t' phase in the “zirconium dioxide stabilized with yttrium oxide” system. Affinity of Hf+4 and Zr+4 cations leads to the formation of identical metastable phases during rapid quenching.

The paper presents a new method for obtaining pulp which is used for production of cardboard, paper and package while using carbon dioxide and hydrazine hydrate and neutral-sulfite shive cooking. Output increase of the desired product can be explained by reduction in destruction of plant raw material carbohydrates during its cooking process. Quality improvement of the desired product (improvement in bleaching and output) is attributed to the fact that usage of carbon dioxide and hydrazine contributes to provision of polysaccharide chain resistance to destruction due to the presence of end links having structure of metasaccharinic and aldonic acids.The author has developed a new method for pulp obtaining on the basis of the executed investigations and literature data. СО2 and hydrazine hydrate have been used for obtaining pulp. Method invention concerns pulp obtaining and it can be used for paper and cardboard package manufacturing in pulp and paper industry.The method is to be carried in the following way: pulp-containing plant raw material is loaded into an autoclave and then aqua solution of sodium monosulfite containing hydrazine hydrate that constitutes 4–5 % of absolute dry pulp-containing raw material mass with liquid module 1:6–1:8 is supplied into the autoclave. The autoclave is closed for operation under pressure and the solution is carbonated under pressure which constitutes 5–8 % of absolute dry plant raw material (shover). Temperature is subsequently raised up to 180 °С in the space of 2 hours and cooking is carried out in the course of 4 hours. Usage of the proposed method for shover cooking makes it possible to reduce monosulfite cooking process and improve qualitative characteristics and output of the desired product. In addition to above mentioned fact there is a possibility to improve bleaching and final product output.

The paper investigates vibro-protection conditions for “operator-chair” system of a transport facility (“Belarus-tractorfamily). Experimental research for the system vibroloading with due account of elastic shock-absorbing characteristics, operator’s comfortability. The paper has made it possible to determine a range of the system vibration frequency which is badlysustained by the operator because the last is located in the zone of natural frequency of human visceral organs vibrationsInfluence of physiological operator’s factors – heartbeat rate, variational height, mode amplitude, stress index has been investigated on the basis of a factor experiment and correlation dependences have been obtained in the paper. The developed methodology for investigation of algorithmic provision pertaining to better active vibroprotection of the “operator-chair” system presupposes an availability of mathematical model used for synthesis of control laws and selection of algorithms for formation of signals on physiological operator’s state. Structural algorithm scheme for vibroprotection of “driver – seat – road” system has been drawn in the paper. Harmonic sinusoidal and poly-harmonic disturbances from the side of a power unit and discrete algorithms based on filtration of white noise with a linear filter and prescribed correlation function have been accepted as a mathematical model for external environment disturbances. In case of harmonic excitation of “operator – chair” system a force transferred to the system by a shock-absorber and also shock-absorber efficiency evaluation in the form of force transmission coefficient and vibration insulation value are estimated at decibels. Fourier’s series describes motion of the system in case of vibration forces initiated by the operation of the power unit. Piecewise-linear function describes a reaction on impact excitation of the system when final change in speed and motion quantity occurs. Quality evaluation of the vibro-protection system is determined as ratio of maximum effort transmitted by the system to maximum value of impact excitation. Decision support system, in otherwords a controlling system, consists of two circuits: the first circuit organizes work with information forming correlations between great number of input and output signals and the second circuit consisting of blocks for state evaluation and decisionmaking organizes work with qualitative information.

The paper considers a problem pertaining to reduction of the Armed Forces of the Republic of Belarus and necessity to carry out economically reasonable reforms optimizing strength of financial personnel with the purpose to decrease its number but without undermining financial and operational activities of the Armed Forces as a whole. It has been proposed to optimize strength of financial personnel in the Armed Forces while executing organizational staff transformations such as introduction of a centralized accounting system for service personnel by an example of the Ministry of Defense of the Russian Federation.Normative for financial personnel strength of the supposed unified financial centre which is involved in accounting recordings on salary and other payments has been calculated on the basis of inter-branch standards. While taking as an example a conventional organization “B” with staff strength which is equal to the strength of the Armed Forces of the Republic of Belarus the possible efficiency in introduction of the centralized accounting system for service personnel has been determined in the paper. According to represented calculations reduction of financial personnel dealing with accounting recordings on salary and other payments in the whole organization “B” can constitute up to 60 persons with more than 200 branches which are carrying out independent payment accounting for personnel concerned.Dependence of strength normative on number of financial bodies, percentage of personnel receiving payments through a unified financial centre and concentration of financial and economic document circulation has been determined in the paper. It has been pointed out that it is not sufficient to determine quantitative indices in order to ensure an objective reflection of the efficiency of possible introduction of the centralized accounting system for service personnel in the Armed Forces. In order to obtain complete information it is necessary to consider qualitative changes paying a special attention to problems and possible ways of their solution. The paper describes problems pertaining to labour norming and it is of interest for financial-economic and organizational and mobilization bodies of the Armed Forces.

The paper considers a problem of the market relations development in the Belarusian housing area. It has been noted that the situation in transition to the market is characterized by vague notion of the State participation extent in solution of the housing problem. Thus the excessive rigidity is observed which is expressed in State intention to shift burden of responsibility for housing provision and exploitation to the forming class of housing owners. Low productivity of such actions is caused by discrepancy of basic provisions in housing reform to the national social and economic development level. The proposed housing policy strategy leans on an assessment of the State participation extent in the formation of separate market functions, i.e. reproduction (production), operation of real estate objects in the housing sphere and transfer of ownership. State participation extent is expressed in establishment of a rigid, partial regulation or assistance in formation of a market selfregulation.Approaches of ordoliberal housing policy adapted for conditions of transition to the market are considered as basic ones for the investigation of the Belarusian housing policy. An idea about the maximum possible expansion necessity of the market housing relations under the rigid state control of activity in the market is realized in the proposed housing policy strategy. This approach has been justified by an intention to prevent possible speculations in housing, monopolization of the market from the side of large commercial structures that directly leads to aggravation of the housing problem. A special attention has been paid to a social subsystem of the market as a condition of social and economic stability of the State. The paper presents an effect calculation from introduction of the proposed housing policy strategy actions.

The paper offers a new method for approximate solution of one type of singular integral equations for elasticity theory which have been studied by other authors. The approximate solution is found in the form of asymptotic polynomial function of a low degree (first approximation) based on the Chebyshev second order polynomial. Other authors have obtained a solution (only in separate points) using a method of mechanical quadrature and though they used also the Chebyshev polynomial of the second order they applied another system of junctures which were used for the creation of the required formulas.The suggested method allows not only to find an approximate solution for the whole interval in the form of polynomial, but it also makes it possible to obtain a remainder term in the form of infinite expansion where coefficients are linear functional of the given integral equation and basis functions are the Chebyshev polynomial of the second order. Such presentation of the remainder term of the first approximation permits to find a summand of the infinite series, which will serve as a start for fulfilling the given solution accuracy. This number is a degree of the asymptotic polynomial (second approximation), which will give the approximation to the exact solution with the given accuracy. The examined polynomial functions tend asymptotically to the polynomial of the best uniform approximation in the space C, created for the given operator.The paper demonstrates a convergence of the approximate solution to the exact one and provides an error estimation. The proposed algorithm for obtaining of the approximate solution and error estimation is easily realized with the help of computing technique and does not require considerable preliminary preparation during programming.

The paper considers a model of damage accumulation in parts of machines and structures which is based on a theory of fractals. Hidden process of destruction prior to the formation of macroscopic cracks is usually associated with the accumulation of micro-damages. Various models of damage accumulation and crack growth under the influence of power and thermal loads. However, models describing the accumulation process of micro-damages and their outgrowth into macro-crack are practically non-existent. Fractal structures with self-similarity are an adequate model of the fracture process. The MacDonald correlation function describing the medium structure allows to present the self-similarity of structures within a certain range of scales.The paper reviews models of damage accumulation near an opening in a composite medium and at layer boundaries. The Cantor model in a forward algorithm and a backward algorithm have been used in order to describe the model of damage accumulation. As it is known, the Cantor fractal (Cantor dust) is obtained by using a recursive algorithm being applied to fracture mechanics can be regarded as a model of stepwise formation of dispersed micro-damages. The process of damage accumulation (latent destruction phase) and its transition in the formation process of macro-cracks and their unification in a through-thickness crack can be described, for example, by the Paris' law.

The paper presents a modeling of non-stationary processes while making arc welding in the shielding gas medium of X-shaped joints which consist of re-bars having various diameters. Changes and specific features of stress-strain state in the X-shaped joint have been considered in the paper. Calculations are as much as possible approximated to a real situation: a 3D-geometrical and finite-element model is used, the problem is considered as elastic and contact one with due account of power loading. An analysis of the welded assembly consisting of re-bars with diameter of 4-10 mm has been performed using a finite element method. Computation of a welded connection with due consideration of geometrical nonlinearity has been done in the paper. It has been shown that tensile of re-bars under load causes uneven stress distribution in a welded joint and their significant concentration is observed at crossing points from the welded joint to a base metal. An analysis of the obtained equivalent stresses at nodes and details of the welded joint structure has shown that they did not exceed permissible values for all diameters in case of the considered loading conditions. A comparison of stress values calculated has been carried out in accordance with the proposed method and experimentally obtained data. It has been revealed that application of tensile load (determined experimentally) to the connection stress values at the connection and welded joint boundary reach an yield strength and subsequently it causes destruction of the connection. It has been established that the margin of safety for such type of connections is averagely equal from 30 to 60 %. The submitted calculated data are in full agreement with experimental data that proves correctness in selection of calculation schemes and loads.

In Belarus concrete with strength up to 60 MPA is used for construction. At the same time high strength concrete with compressive strength above 60 MPA is widely used in all industrially developed countries. High- strength concrete is included in regulatory documents of the European Union and that fact has laid a solid foundation for its application. High strength concrete is produced using highly dispersed silica additives, such as micro-silica and plasticizers (super-plasticizers) with a water/cement (w/c) ratio not greater than 0.4.Theoretical aspects of high-strength concrete for bridge structures have been studied in the paper. The paper shows a positive impact of highly dispersed additives on structure and physico-mechanical properties of cement compositions, namely: reduction of total porosity of a cement stone in concrete while increasing volumetric concentration and dispersion of a filler; binding of calcium hydroxide with the help of amorphised micro-silica; increased activity of mineral additives during their thin shredding; acceleration of the initial stage of chemical hardening of cement compositions with highly dispersed particle additives that serve as centers of crystallization; “binder-additive” cluster formation due to high surface energy of highly dispersed additive particles; hardening of surface area between a cement stone and aggregates in concrete; high-strength concretes are gaining strength much faster than conventional concretes.Technology of preparation and composition of high-strength concrete using highly dispersed mineral additives and super-plasticizer has been developed in the paper. This concrete will ensure a higher density, wa- ter-and gas tightness, increased resistance to aggressive environment, reduced consumption of concrete and reinforcement, reduced transport and installation weight, increased initial strength, early easing of shutters and preliminary compression, increased length of bridge spans, reduced cross-section of constructions while preserving construction bearing capacity, taking bending moment primarily. Improvement of bridge structure durability makes it possible to increase a period between maintenance that will lead to significant savings in material and labor resources. In the near future there will be a gradual replacement of the conventional traditional concretes with multicomponent concretes.

Usage efficiency of mechanical engineering products is determined by level of their operating capability. Expenses connected with provision of operating capability for the whole operational period exceed initial cost of the products by 6-10-fold. Moreover , while being used the expenses have a tendency to increase with reduction of output parameters that ensure product application efficiency for its intended purpose. It is necessary to take into account these changes at manufacturing stages of mechanical engineering products. Maximum efficiency can be obtained at the operational stage of the product life cycle only as a result of complex and interrelated measures during designing, manufacturing and usage of the specific product for its intended purpose with due account of its output parameter dynamics. While using the product an analysis of its output parameter dynamics will make it possible to determine maximum value of the operating capability, operational expenses and best practices for obtaining maximum profit per operating time unit.Taking hydroficated excavators of the 5th grade as an example the paper presents dynamics of main output parameters at the operational stage of their life cycle; reveals the main factor influencing on intensity of hydroficated machine operating capability reduction; substantiates an expediency of taking into account output parameter dynamics while evaluating efficiency of its usage; proposes a methodology for determination of or a pay-off time period for recoupment of expenses pertaining to machine procurement and optimum time period for operational stage, its life cycle that corresponds to obtaining maximum profit.Nowadays constant values of main output parameters (operating capability, self cost of machine-hour) corresponding to the beginning of operation are to be taken into account while determining expediency of machine creation. Practically they significantly change in the process of machine operation this fact must be taken account while creating a machine and using it for its intended operational purpose and ensuring its operating capability. The proposed methodology for maintaining and restoration of operating capability of construction and road-building machines was published previously [3]. The paper proposes a methodology for its implementation on the basis of expenses for machine manufacturing and dynamics of main output parameters at the operational stage of its life cycle.

The paper presents results of investigations on rational usage of mineral resources. In particular, it has shown the possibility to increase a period of raw material serviceability and its application for production of building products depending on chemical and mineralogical composition of the waste. Analysis of the executed investigations shows that import substitution of anthracite, lignite and black coal for local fuels (milled peat and its sub-standard product) is possible in the production technology of porous building materials.A mathematical model for drying process has been developed in the paper. Technology for thermal performance of a sintering machine with calculation of its length at the given pallet speed has been proposed on the basis of the developed model. Once-through circulation of flue gases and heated materials is the main specific feature of belt sintering machines being used in production. In such a case the whole drying process can be divided into two periods: a period of constant drying rate and a period of falling drying rate. Calculations have shown that the drying rate depends on moisture content but it does not depend on heat exchange Bio-criteria, however, heating rate is a function of temperature and Biq. A mechanism of moisture transfer using various drying methods is the same as in an environment with constant temperature and so in an environment with variable temperature. Application of the mathematical model provides the possibility to save significantly power resources expended for drying process.The paper gives description of methodology for calculation of technologically important optimum parameters for sintering processes of agglomeration while using milled peat.

Presently bitumen-mineral materials (including asphalt-concrete) comprise nearly 98 % for construction of expensive road pavement. Large resources of local minerals (quartz sand) and industrial wastes in the form of used molding sand (foundry by-product) are widely applied for reduction of their cost. Such approach is economically and ecologically reasonable but it requires its justification because an adhesion interaction in the bitumen-quartz substrate system (with SiO2 more than 95 %) is rather poor in natural state and due to water action it is still more decreasing. In this connection an objective necessity arises to modify significantly technology of bitumen-mineral compositions for ensuring reliability of road pavements while using silicon components.All the ideas pertaining to strengthening of adhesion bonds in the “quartz mineral substrate - bitumen” system are traditionally of physical and chemical nature and they presuppose mainly usage of colloidal chemistry methods. The paper considers the matter on the basis of molecular kinetic theory of matter taking into account the fact that there is absence of generally accepted calculations for intermolecular interactions of components in the SiO2 - organic matrix material system.As a theoretical supposition the following well-known regulatory principle in physics is used: as every atom or molecular have its own electromagnetic field then action of external electromagnetic fields initiates their interaction that leads to excitement of electrons, deformations and rupture of chemical bonds. Literature analysis shows that the existing electric bonds between components of the SiO2 - organic matrix material system provide the possibility to apply various electro-physical methods having an effect on these components with the purpose to strengthen their adhesion interaction.The paper investigates matters for determination of bond energy during physical adsorption and adhesion in the SiO2 - organic matrix material system with due account of the indicated principles.

The paper is devoted to problems pertaining to renovation and new construction of drainage systems in accordance with the State program on conservation and use of reclaimed agricultural land of the Republic of Belarus. It has been It has been established on the basis of the analysis of soil, hydrological and topographic surveys at eight renovation and new construction sites that overwatering of agricultural land is mainly derived from silting of channels, drains and sewer mouths; poor organization of surface water runoff from fields and compaction of subsurface horizon.Project activities have been conducted in accordance with existing regulatory documents. Polyethylene corrugated pipes have been used while designing new facilities and renovation of existing drainage systems. Diameters of plastic collectors have been calculated from well-known hydraulic formulas depending on drainage flow module and catchment area. Surface low-country runoff has been driven mainly by gullies, open craters and wells sinks. Composition of technical solutions used in the reconstruction of reclamation systems has been determined not only by hydrological conditions and a high-tech state of elements in the existing drainage system, but also by planned agricultural use of reclaimed land.The paper considers some examples pertaining to application of various approaches to the objects of new reclamation construction on fertile soil and reconstruction of reclamation systems under different soil and hydrogeological conditions of the Republic. Main technical and economic indicators are given in the paper. It has been shown that technical solutions incorporated in the projects of new construction and reconstruction of reclamation systems provide significant improvement in soil water regime and their effective agricultural use.

Due to growth of number of storeys in a dwelling and public buildings for mass gatherings (up to 20-25 storeys) requirements of their construction industrialization necessitate designs of precast column joints which are capable to bear high loads (up to 10-12 МН and more). The paper presents an analysis of the known contact joint designs used in the columns of frame buildings and the analysis shows that the these design are rather efficient. However these joints are sensitive to accuracy of column butt end fabrication. Bearing capacity of joints can be significantly decreased in case of comparatively small ends out of square. It has been decided to introduce a deformable centering laying made of soft steel in a joint design in order to exclude the mentioned disadvantage. Due to its plastic deformation the laying ensures transformation of longitudinal effort occurring in it to the column axis. As a result of it we obtain the most advantageous position for joint design required for transfer of compressing force at column longitudinal axis.Experimental investigations of contact joints with a deformable centering laying have been carried with due account of the requirements to construction standards, results of the executed works and main results of the investigations are presented in the paper. Proposals for calculation and designing of these joints have been given on the basis of the obtained data and works. It has been shown that application of the centering laying with corresponding concrete confinement reinforcement at the joint make it possible to ensure the required bearing capacity and reliability.

The paper describes development of the methodology for optimization of parameters for an additional operating force mechanism in a device for pneumo-centrifugal machining of glass balls. Specific feature in manufacturing glass balls for micro-optics in accordance with technological process for obtaining ball-shaped workpieces is grinding and polishing of spherical surface in a free state. In this case component billets of future balls are made in the form of cubes and the billets are given preliminary a form of ball with the help of rough grinding. An advanced method for obtaining ball-shaped work-pieces from brittle materials is a pneumocentrifugal machining. This method presupposes an application of two conic rings with abrasive working surfaces which are set coaxially with large diameters to each other and the billets are rolled along these rings. Rotation of the billets is conveyed by means of pressure medium.The present devices for pneumo-centrifugal machining are suitable for obtaining balls up to 6 mm. Machining of the work-pieces with full spherical surfaces and large diameter is non-productive due to impossibility to ensure a sufficient force on the billet in the working zone. For this reason the paper proposes a modified device where an additional force on the machined billet is created by upper working disc that is making a reciprocating motion along an axis of abrasive conic rings. The motion is realized with the help of a cylindrical camshaft mechanism in the form of a ring with a profile working end face and the purpose of present paper is to optimize parameters of the proposed device.The paper presents expressions for calculation of constitutive parameters of the additional operating force mechanism including parameters of loading element motion, main dimensions of the additional operating force mechanism and parameters of a profile element in the additional operating force mechanism.Investigation method is a mathematical simulation of the operating zone of the device for pneumocentrifugal machining.

The purpose of the presented paper is to optimize technological parameters of hardening high-energy processing used for sprayed coatings made of materials based on oxide ceramics with inclusions of solid lubricant. The paper presents results of the investigations on influence of power density and total number of laser irradiation impulses in a spot treatment on thickness of treated coating layers made of materials based on oxide ceramics. The considered wear-resistant coatings require increased cohesive and adhesive strength. Therefore, the total number of impulses should ensure melting and sealing of the coatings along the whole thickness that will fully contribute to obtain hardened nano-crystalline and amorphous structures.The work is based on complex metallography, X-ray diffraction and electron-microscopic investigations on modified structural elements of composite coatings being treated with highly concentrated energy sources. The following main processes of hardened plasma coating formations have been revealed in the paper: com paction of sprayed materials due to thermal and shock-wave impacts of laser irradiation impulses. In this case material porosity is decreasing, cohesive and adhesive strength of coatings is increasing, grain structure is crushed, amorphous and nano-crystalline phases of higher strength are formed all these facts are evidenced by an increase in average micro-hardness of deposited compositions. Duration of thermal laser irradiation impulse impact on the material is sufficient to activate chemical processes in the boundaries of main phases of the composite coating. This leads to formation of finely dispersed (including nanoparticle size) compounds that strengthen boundaries of the main phases and the coating as a whole. This is confirmed by the results of an X-ray diffraction analysis.

The paper has investigated influence of various technologies on recycling of vegetal raw material with the purpose to obtain the desired product used for package printing. Influence of various technological regimes and introduction of fresh polyethylene additives for recycled raw material on qualitative indices of the desired product has been studied in the paper. Investigations of preliminary aquatic hydrolysis of vegetal raw material have shown that in order to obtain high quality cellulose from vegetal raw material it is necessary that this cellulose has not less than 2-3 % of hemicellulose otherwise its qualitative indices are significantly deteriorated that is important for packaging printing. Usage of carbon dioxide aqueous solution for preliminary vegetal raw material hydrolysis contributes to reduction in destruction of cellulose carbo-hydrate. This improves qualitative indices of the obtained desired product that is cellulose which is used for package printing.Recommendations for sulphate pulping of vegetal raw material with preliminary hydrolysis have been prepared with the purpose to improve physical and mechanical characteristics of the obtained desired product - cellulose on the basis of the obtained data on content of hemicellulose in cellulose.While investigating recycled polymers the obtained results have demonstrated that increase of low- molecular product content in them looks rather typical. This suggests that packaging will have lower qualitative indices while using polymers being kept in waste deposits. In order to avoid this phenomena it is necessary to add 20-30 % of fresh polymers during their recycling.

The paper considers an influence of a cutting zone cooling method on the chip shape and thickening ratio while turning R35 steel with the hardness of НВ 1250 МРа. Cutting with various types of cooling - dry, compressed air and emulsion fog has been investigated in the paper. OPORTET RG-2 emulsol with emulsion concentration of 4% has been used as an active substation. Cutting tool is a turning cutter with a changeable square plate SNUN120408 made of Р25 hard alloy with multilayer wear-resistant coating, upper titanium nitride layer. Front plate surface is flat. Range of cutting speeds - 80-450 m/min, motions - 0,1-0,5 mm/rev, emulsion flow - 1,5-3,5 g/min and compressed air - 4,5-7,0 m3/h, cutting depth - 1,0 mm. In order to reduce a number of single investigations it is possible to use plans based on ЛПх-sequences.It has been shown that the method for cutting zone cooling exerts significant influence on conditions for chip formation. Regression equation describing influence of machining conditions on Ка-chip thickening ratio has been obtained in the paper. The range of cutting modes is extended while using emulsion fog for cooling. In the process of these modes chip is formed in the shape of short spiral fragments or elements. Favourable form of chips is ensured while using the following rate of emulsion - not more than 2 g/min. The investigations have made it possible to determine conditions required for cooling emulsion fog. In this case it has been observed minimum values in chip thickening ratio and chip shape that ensures its easy removal from cutting zone. While making dry turning values of Ка is higher not less than 15 % in comparison with other methods for cutting zone cooling.

The paper presents a schematic diagram of the powertrain automated control system based on dry friction clutch and manual gearbox. Mechatronic system has a modular configuration and allows to make the vehicle starting-up, low speed maneuvering and command or automatic gearshifting. Diesel engine, clutch and 10-step gearbox control is carried out at all movement modes by electronic modules when affected on mode selector, accelerator pedal and, if necessary, on brake pedal. Data exchange between electronic units is carried by SAE-J1939 protocol with a transmission rate of 250 kbit/s. Change in diesel fuel supply, clutch engagement and gearshifting take place automatically as a result of pneumatic power actuator operation by a signal from the controller to the corresponding solenoid valve or a combination thereof.Presents the results of semi-natural experiment on research of gear shifting process in the command mode of powertrain control. Transient gearshift oscillograms with various control algorithm structure have been given in the paper. The paper contains a ^iT^rative analysis of the oscillograma and a conclusion on expediency of gear shifting automation. A graphic representation of the semi-natural experiment results has been performed with the help of CoDeSys V2.3-visualization facilities.

Nowadays heavy vehicles constitute a considerable volume in the transportation flow on the territory of the Republic of Belarus and bridge inequalities significantly increase a load on their bearing elements and cause a vibration in bridge superstructures. This leads to rapid wear and reduction in time between bridge repairs. The given problem has been insufficiently studied and it is considered as an actual one. Revision of analytical models is required in order to make prediction and evaluation of bridge structure wear. These models must take into account a dynamic impact of heavy vehicles caused by their movement on bridge rough riding surface.The purpose of scientific investigations is to develop a dynamic interactional model of a vehicle and a bridge plate. The paper proposes such dynamic model that permits to investigate impact forces of a heavy vehicle on bridge superstructures which have been initiated by bridge traffic-way inequalities. Weight of an vehicle and plate, rigidity and viscous damping of vehicle suspensions, a plate and piers have been taken into account while making the required calculations.An analysis of free oscillatory motions of the plate and vehicle have been carried out with due account of viscous damping. A dynamic interactional calculation for a vehicle and a plate has been made in the paper. Character of plate oscillatory motions has been determined at various parameters of the dynamic model. In this case non-linearity of reinforced concrete plate deformation has been taken into account and its calculation has been executed in accordance with the norms of the Republic of Belarus. The calculations have made it possible to obtain dynamic interaction coefficients of front axle wheels and bridge plate at various bench heights and also investigate its influence on maximum bending moments in plate sections.