The paper provides an experimental evaluation pertaining to the influence of steel self-tapping screw on its twisting-in specimens made of various materials and its twisting-out process. Main principles of the investigation methodology including description of  technological scheme of self-tapping screw electro-arc machining and specimens applied while executing the experiments and hardware measuring tools used for fixation of torque which has been applied to the self-tapping screw during its twisting-in in the specimen  and its twisting-out process have been presented in the paper. It has been established that the self-tapping screw electro-arc machining initiates formation of dimples (holes) which have solidified metal flows along their edges. The flows give a cutting ability to the screw and so they exert an influence on the conditions of screw’s interaction with the specimen during its twisting-in and twisting-out processes.

The paper presents results of experimental investigations that demonstrate an impact of self-tapping screw electro-arc machining on its twisting-in in the specimens made of various materials and twisting-out procedure. In particular, it has been ascertained that torque value applied to the self-tapping screw with modified surface during twisting-in process is less in comparison with the self-tapping screw having an initial state of its surface and in the case of its twisting-out process the value is higher. In this respect difference between the indicated torque values is increasing when material hardness of the specimen becomes higher. 

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.

Engineering machines being in operational service with military units of  engineer troops are fit to their purpose and their application is relevant in modern conditions. Maintenance of operating conditions in engineering equipment which was produced earlier by the USSR enterprises is considered as a rather complicated task due to lack of spare parts because their production has been discontinued.

One of the approaches used for maintenance of engineering equipment combat capabilities is modernization of operating drive systems that presupposes replacement of mechanical systems in working element drives by hydrostatic drives which are realized while using modern element base. Usage of hydraulic units in drive systems being in mass production for replacement of mechanical systems manufactured earlier in small batches makes it possible to reduce labour inputs for maintenance and repair of machines. The paper presents some possibilities for development of operating drive systems in engineering equipment. The proposed approach is given through an example of  engineering obstacle-clearing vehicle (IMR-2M) and excavation machines (MDK-3 and MDK-2M).

Application of a hydraulic drive in working elements of the excavation machines permits to withdraw from cardan  shafts, a gear box, a rotary gear and an overload clutch. A hydraulic motor of the cutter and thrower drive is mounted  on a working element gearbox. While executing modernization of hydraulic systems in excavation machines a pump unit has been proposed for the cutter and thrower drive which consists of a controlled pump and a system for automatic maintenance of the pump operational parameters. While developing the operating drive systems in engineering equipment in accordance with the proposed requirements it is possible to simplify drive systems of working elements and  ensure reliable machinery operation in the units of engineer troops. 

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.

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 paper considers a transportation system of  one poorly developed region of the Eastern Siberia where it is planned to make investments for improvement of the corresponding infrastructure. The efficient investment disbursement presupposes study of the existing demand for transport services in the field of passenger traffic.  Results of the observations can be used for development planning of a road network and a bus service system.

Due to lack of direct data on the existing demand efforts have been made to obtain its model description while using modified gravity models that make it possible to estimate  volumes of population transportation which is carried out between residential areas by public transport buses and private vehicles. The given models have permitted to make analysis of more than 5000 populated locality pairs for 86 residential areas where the population constitutes more than 80 % and its passenger flow formation component in equal to 60%. Traffic flows between these settlement pairs have been estimated with the help of gravity models with various attraction functions and Arrowsmith method for provision of transportation balances. The most adequate results have been obtained while using an exponential attraction function for individual vehicles and a power attraction function  for passenger route auto transport. Such approach is consistent with the preference of the route auto transport in case of long-distance transport service. A tree-like structure of the existing traffic system has given the possibility to avoid consideration of  alternative routes in case of passenger transportation and directly calculate transport flows for certain road sections. Comparative analysis of the transport flows using the proposed methodology and the existing partial data of the executed observations reveals  satisfactory coincidence of empirical data for the main part of the traffic system. The obtained results demonstrate an efficiency of the described approach and the presented data can be used as a benchmarking tool for transport planning.

Accidents are considered as the most significant cost of road traffic. Therefore any measures for road traffic management should be evaluated according to a minimization  criterion of accident losses. In order to develop a method for evaluation of the accident losses it is necessary to prepare a methodology for cost estimate of road accidents of various severity with due account of their consequences and prediction (economic assessment) and severity level of their consequences (quantitative risk assessment). The research has been carried with the purpose to devise appropriate models for accident prediction at a decision-making stage while organizing road traffic in respect of  the “transport-pedestrian” conflict. An interaction of pedestrian and transit road traffic flows  is characterized by rather high risk level. In order to reduce number of road accidents  and  severity of their consequences in the observed conflict, it is necessary to evaluate  proposed solutions, in other words to predict accidents at the stage of object designing and  development of measures.

The paper presents its observations on specificity of road traffic and pedestrian flow interactions and analysis of spatial conflict point formation and conflict zone creation in the studied conflict between transport facilities and pedestrians at controlled pedestrian crossings which are located in the area of intersections. Methodology has been developed for accident prediction in accordance with the conflict zone method for various traffic modes at intersections. Dependences of the represented road traffic accidents (according to consequence severity) on potential danger of conflicts have been determined for various traffic modes and various conditions of conflict interaction.

The executed investigations have made it possible to ascertain that a morphological structure of starch granules mainly determine technological peculiarities of starch isolation from raw material, its modification and its later use. Morphological structure of starch granules primarily depends on type of plant starch-containing raw material which has been used for its isolation. Class of raw material exerts a strong impact on the shape and size of the granules. Linear “light” amylose chains and “heavy” amylopectin branch chains form a starch granule ultrastructure. X-ray research has proved that starch granules are characterized by presence of interlacing amorphous and crystalline regions. In this case polymer orientation using stretching of the obtained end product influences on its physical and mechanical  indices which are increasing due to polymer orientation. For the purpose of packaging orientation of polymer films can solve such important problems as significant improvement of operational properties, creation of  thermosetting film materials, improvement of qualitative indices of the recycled film.

Results of the conducted research have proved the fact that it is necessary to make changes in technology in order to increase biological degradability of the recycled packaging made from polymers and improve physical and mechanical indices. In this regard film production technology presupposes usage of such substances as stark and others which are characterized by rather large presence of branch chains of molecules and interlacing amorphous and crystalline regions. Such approach makes it possible to obtain after-use package which is strong and quickly degradable by micro-organisms.

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.

Nowadays mathematical modeling of peculiar features of a stress-strain state is considered as a perspective direction of research. In this regard the aim of this paper has been to make calculations of the stress-strain state initiated by a system of parallel lenticular residual mechanical twins that occur due to local surface deformation of  Ni₂MnGa single crystal martensitic phase.

The method is applied while using a superposition principle of fields and approximation of a continuous distribution of twinning dislocations on twin boundaries in a continuous elastic medium.

The calculations have made it possible to obtain distribution graphs of displacement fields and stresses and point out the fact that a configuration of displacement component distribution u_y is significantly different from the displacement of components u_x and u_z having a displacement distribution similar to each other. The highest value of displacement occurs in the component u_y in twins peaks.

The paper also presents results of calculations for six components of a stress field the tensor. The obtained results have revealed similarity in stress distribution character of the components  s_xz and s_zz, but they differ numerically from each other about in two times. The largest value of the stresses occurring in the lenticular twins has been observed in components s_xx, s_xz, s_yy, s_yz and it has been focused mainly at the borders and peaks  of twins.

A common feature of the obtained components of displacement and stresses in a lenticular twins system is symmetry with regard to OY. In addition, the stress distribution of all obtained tensor components has been mainly localized at the borders and at the tops of twins where the highest values of stresses capable of exerting a significant impact on dislocation and diffusion processes are generally concentrated.

The paper considers a control scheme of such optoelectronic devices with matrix photo-detectors as  autocollimators, microscopes, star trackers and other film equipment an d the control is carried out with the help of a collimator. A number of factors (structure discreteness, photo-detector noise, consistency in collimator test-object size, photo-detector pixel size and point scattering function of optical components) exert an influence on control accuracy.

In the context of control problems and alignment of optoelectronic devices the paper studies a scheme which includes two components: controlling component that is a collimator and a component to be controlled that is a tele-centric system). A mathematical model for control schemes has been proposed with the purpose to determine an effect of the above-mentioned factors and its mathematical implementation has been described in the paper.

Due to simulation an optimal ratio has been selected for component parameters of the optical control scheme: point scattering function for a collimator objective and a telecentric system,  collimator test-object size, photo-detector pixel size.  A collimator test-object size has been determined in the paper. Using the considered scheme the size will give the smallest measurement error caused by photo-detector discreteness of a controlled device. A standard deviation of the gravity energy center for a collimator test-object caused by photo-detector noise has been determined in the paper. In order to reduce the effect of photo-detector noise the paper proposes to take as zero values of a signal such values which are smaller than a doubled discretization interval of an analog-to-digital converter.

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.