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In recent years, intensive research on urban transport has been observed. The search is about finding such solutions that will enable, among others: increasing the importance of public transport, matching transport for the needs of people with reduced mobility, increasing capacity, reducing emissions, energy efficiency (technical and organizational dimension through the organization of transport on demand), increasing the vulnerability to recycling and remanufacturing. The paper presents the main concept and technical solutions of the innovative transport system – HMASSUT Prometheus (Hybrid Modular Autonomous System for Sustainable Urban Transport), which combines the concepts of personal rapid transport and an electric vehicle at the L4 autonomy level (according to the Society of Automotive Engineers classification). An assessment of the effectiveness of an innovative transport system using indicators used in road engineering is given in the paper. The concept of simulation and optimization of the transport network is presented together with the theory of cellular automata.

In the operation schemes of optical electronic devices (OED), such as digital autocollimators, direction finders, Shack-Hartmann sensors, as well as astro-orientation systems, projection measuring systems, geometric calibration schemes for OED, the photo-detector acts not only as a receiving device, but also as a measuring device. The tasks facing the OED photo-detectors. The solution to the problem is the use of several photo-detectors installed on one electronic board. Since OED photo-detectors act, inter alia, as measuring devices, it is necessary to perform their geometric calibration. Geometric calibration involves the measurement of interior orientation parameters used in the processing of OED images. Geometric calibration makes it possible to eliminate errors in mutual exposure of photo-detectors on one electronic board installed in the focal plane, as well as distortions introduced by the OED lens, primarily by distortion. The correctness of the interior orientation parameter determination is influenced by the relative position of the collimator, with the help of which the geometric calibration is performed, and the calibrated OED itself, i. e. the external orientation elements. The task is to separate the interior orientation parameters and the elements of external orientation. This is achieved using the method of mathematical processing of measured data in the forward and inverted positions of the collimator. This method of geometric calibration allows to use it for geometric calibration of OED with a large number of photo-detectors. The paper presents the results of the geometric calibration of the interior orientation parameters when the collimator projects a test object onto three photo-detectors of the OED layout. The factors influencing on the accuracy of the geometric calibration of the interior orientation elements for OED are determined in the paper. The developed method for geometric calibration of the interior orientation parameters for multi-matrix OED provides high measurement accuracy – not more than 0.1''–0.2''.

Nowadays there are a lot of modern technologies in electronic lexicography: speech synthesis technology, cross-referencing between dictionary modules, spell-checking functions, etc. The increasing availability of online information has necessitated intensive research in the area of automatic text summarization within the Natural Language Processing community. Belarusian scientists are also interested in this sphere and new lexicographical approaches for creating a linguistic database are shown in the paper. The authors present English-Belarusian-Russian electronic dictionary TechLex. This is the project of the 2nd English Department and the Department of Software for Information Systems and Technologies of the Belarusian National Technical University. The linguistic database of the dictionary is compiled not by the traditional method of processing a large number of paper dictionaries and combining the received translations, but by sequential processing of scientific and technical English-language periodicals. While the designing the dictionary the authors have taken into account the analysis of modern electronic multilingual translation dictionaries and created a client-server application in the Java programming language. The client part of the system contains a mobile application for the Android operating system, which has been tested on tablets and smartphones with different screen diagonals. The interface of the TechLex dictionary is designed taking into account the possibility of adding new subject areas and filling them with appropriate lexical material. The main advantage of our dictionary is that it is the first technical multilingual electronic dictionary having a Belarusian version.

Studies on the influence of applying various technologies for combustion knock reduction have been presented in the paper. Among others, investigation concerning the following: over-expanded cycle, variable valve timing, internal and exhaust gas recirculation, leaning the combustible mixture and cooling the in-cylinder charge were of the interest. The research works were focused on impact of these technologies on both knock intensity reduction, and engine performance and toxic emissions. Results presented in the paper were coming from experimental investigation based on in-cylinder combustion pressure data acquisition. Additionally, knock intensity calculation methods were discussed. They are based on incylinder combustion pressure pulsations. Combustion knock intensity expressed by the maximum peak of the incylinder pressure pulsations shows a strong negative correlation with both the EGR ratio and relative equivalence ratio – lambda. With respect to a catalytic converter installed on the exhaust pipe line, applying EGR appears as better solution for knock reduction then leaning the combustible mixture because the catalytic converter needs stoichiometric mixture for effective NO x reduction. Furthermore, application of the over-expanded cycle to the hydrogen or coke gas fueled IC engine significantly reduces intensity of potential knock by 50 % in comparison to Otto cycle for all loads. Additionally, over-expanded cycle contributes to increase in engine thermal efficiency. Summing up, all the presented measures and technologies can be successfully implemented into practice in stationary engines as well as in traction engines, both of them working on either natural gas or gaseous renewable fuels.

The paper considers spatial organization of energy facilities with an emphasis on modern practice of the Republic of Belarus. The efficiency of enterprise operation in any industry including power industry is largely due to their architectural and planning organization. Knowledge of mechanisms and specific features of the changes taking place here makes it possible to justify a promising strategy for project activities, and therefore, it allows to manage development processes of the industry and thereby avoid many negative consequences. Energy facilities are a typological unit of industrial architecture, their formation has been started due to transition of industrial production to electric energy. Today the typology shows functional approach in architectural shaping, it includes a fairly large variety of constituent units and demonstrates a tendency towards diversification. In Belarus energy facilities in the architectural aspect of their classification are limited mostly to thermal power plants operating on different types of fuel. Currently the diversification is developing in the following areas: construction of hydropower facilities (small plants on reservoirs, medium power plants, low-pressure plants, run-of-the-river hydraulic power stations), alternative energy (wind power stations, photovoltaic power stations and biogas plants) and conventional energy (thermal power plant, mini-combined heat and power plant operating on renewable fuel). The results of Belarusian practice in construction of all types of facilities (hydropower, alternative and conventional energy), peculiarities of the architectural and planning organization of facilities at the current stage, correlation with global trends in the development of industrial architecture have been characterized in the paper. The paper has determined typological features of alternative energy facility architecture, opportunities and directions for implementation of architectural approaches, problems and prospects to develop scientific support for the project process.

The papers considers the following six innovative models of marketing activity: event marketing, brand immersion, geolocation internet-marketing, lead generation internet-marketing, single commodity distribution and trade-service network, van selling. Even marketing is a systematic execution of events used as a platform for presentation of products while attracting attention of potential consumers and exerting emotional impact on them. The model is directed on four targeted objects: consu-mers, partners, market and own personnel. Brand immersion is the involvement of consumers in emotional perception and expe-rience of brand. Geolocation internet-marketing is data penetration (location) of a large circle of consumers via the Internet on a wide geographic site. Lead generation internet-marketing is attraction (generation) of potential consumers (leads) via the Internet. Single commodity distribution and trade-service network is an aggregate of firms or individuals which and who take over or help to transfer ownership of a particular product or service to someone else on their way from a manufacturer to a consumer as well as providing trade and service services. Links of the commodity distribution network are: manufacturers, distributors, wholesalers, dealers, brokers, agents, consignees, retailers, service and repair companies. Van selling is wholesale trade with prompt delivery of goods to consumers and placing orders on the spot (sale from wheels). The essence of each model has been revealed and their values and advantages in commercial activity have been considered in the paper. It has been shown that an introduction of innovations is hindered by various factors: stereotypes of thinking, organizational difficulties, additional material costs, possible lack of direct economic benefits for some participants in the trade. All this makes it difficult to create and implement innovations in trade practice including the use of computer technologies in trade, for example, in the field of public procurement. The paper proposes methods for eliminating these obstacles.

Hybrid electric powertrains in automotive applications aim to improve emissions and fuel economy with respect to conventional internal combustion engine vehicles. Variety of design scenarios need to be addressed in designing a hybrid electric vehicle to achieve desired design objectives such as fuel consumption and exhaust gas emissions. The work in this paper presents an analysis of the design objectives for an automobile powertrain with respect to different design scenarios, i. e. target drive cycle and degree of hybridization. Toward these ends, four powertrain configuration models (i. e. internal combustion engine, series, parallel and complex hybrid powertrain configurations) of a small vehicle (motorized three wheeler) are developed using Model Advisor software and simulated with varied drive cycles and degrees of hybridization. Firstly, the impact of vehicle power control strategy and operational characteristics of the different powertrain configurations are investigated with respect to exhaust gas emissions and fuel consumption. Secondly, the drive cycles are scaled according to kinetic intensity and the relationship between fuel consumption and drive cycles is assessed. Thirdly, three fuel consumption models are developed so that fuel consumption values for a real-world drive cycle may be predicted in regard to each powertrain configuration. The results show that when compared with a conventional powertrain fuel consumption is lower in hybrid vehicles. This work led to the surprisingly result showing higher CO emission levels with hybrid vehicles. Furthermore, fuel consumption of all four powertrains showed a strong correlation with kinetic intensity values of selected drive cycles. It was found that with varied drive cycles the average fuel advantage for each was: series 23 %, parallel 21 %, and complex hybrids 33 %, compared to an IC engine powertrain. The study reveals that performance of hybrid configurations vary significantly with drive cycle and degree of hybridization. The paper also suggests future areas of study.

A great attention has been recently paid to development of ultrasound technologies for treatment of blood vessels throughout the world. Authors of the paper have developed a new effective treatment method and ultrasound equipment that allow to carry out destruction of intravascular formations with simultaneous increase in elasticity of a vascular wall together with cardiologists from Belarusian Medical Academy of Postgraduate Education and Republican Scientific and Practical Center “Cardiology”. Advantages of the method are absence of necessity in surgical intervention, low probability of complications, low cost of treatment. The main component of the developed ultrasonic equipment is a tube-type stepped concentrator-waveguide having a spherical tip at a distal end with a single axial hole of 0.5 mm-diameter and three radial holes of 0.3 mmdiameter located at an angle of 120° relative to each other. The main effect for application of the concentratorwaveguide is achieved by ultrasonic vibromechanical action of a spherical tip on intravascular formation with subsequent removal of destruction products by their aspiration from a vascular bed. An additional effect is provided due to cavitation action on vascular formation and vessel walls by flow of fluid supplied via an internal cavity of the stepped concentratorwaveguide through the holes in the spherical tip. This contributes to a significant improvement in elastic properties of a vascular wall in atherosclerosis and diabetes. It is necessary to ensure high accuracy and quality of surfaces for the formed microholes in order to achieve maximum efficiency of the cavitation jet impact on intravascular formations and on the vascular wall. According to the analysis results on specific features of existing methods for small-diameter hole shaping, an electrochemical hole cutting method has been proposed which allows to obtain accurate micro-holes with a diameter of 0.3 mm and high surface quality in parts of small cross section and rigidity. The paper presents results of study on effect of electrochemical holes cutting parameters (voltage, concentration and consumption of electrolyte) on size and shape of the formed microholes. Main modes of electrochemical holes cutting process have been developed which allow to form micro-holes in a spherical tip of a tubular concentrator-waveguide with required accuracy, dimensions and shape.

The task of controlling multi-link robots with manipulators for implementation of high-tech processes in industry has been considered in the paper. The paper presents sequential steps of using computer technology in construction of robotic-manipulators, including mathematical, algorithmic, and hardware and software tools for creating a multi-drive mechatronic system controlled by OMRON industrial microcontroller. A kinematic scheme of a robot manipulator has been described in the paper and it performs the following two types of movements – rotation around the z axis and rectilinear movement of a working element along a turning radius with precise positioning at a given point in the working space. Electromechanical design of the manipulator allows to ensure transportation of production objects in accordance with a given technological process. For designing the technological process of transporting production objects, a software module has been developed that makes it possible to automate description of basic operations for movement of the robot manipulator working body with subsequent automatic generation of a command sequence for a control program ensuring operation of electric drives in manipulator links in real time. To speed up the process of designing trajectory of the working body, a spatial simulation model of a robot-manipulator in the MatLab-Simulink environment has been developed. The paper considers a generalized diagram of a mechatronic control system for a robot-manipulator based on the OMRON programmable logic controller operating under control of a program developed in the programming environment Sysmac Studio Automation. A program for a programmable terminal with interface elements and animation elements has been developed for industrial use of the mechatronic system during adjustment and operation period. The paper provides an appearance of a robot-manipulator prototype. The developed mechatronic system of the robot-manipulator can be technologically oriented towards solving other problems of industrial production.

The paper considers principal features and specific character of architectural design for health care institutions. Main designing stages, missions and complexities for every successive designing step have been revealed in the paper. The paper presents specific features, main stages and design approaches to designing of modern health care facilities, comfortable architectural environment of health institutions, which have been formed on the basis of the analysis of advanced international experience in the field of designing healthcare facilities. The proposed approaches are based on modern experience in designing medical buildings over the past decade in the developed countries. A special attention has been paid to obsolete methods for architecture-planning organization of healthcare facilities and modern approaches to arrangement of engineering and other systems which significantly influence on economical efficiency, quality, comfort and effectiveness of architectural environment in healthcare institutions. Every healthcare facility, every separate department are considered as unique in their essence, for this reason it is not so easy to reflect modern technological solutions and architectural tendencies. The paper contains an attempt to attract attention of architects to the complexity in designing of a building to be constructed, to find ways which will help to reach its step-by-step solution. It has been noted as well that there is a necessity to arrange interaction between an architect and a medical technologist. Modern medical departments and hospitals have been recently designed and built in the Ukraine, but they are in increasingly short number. These facilities have been constructed due to decision makers who, in spite of diverse difficulties, lack of information and specialists, lack of proper funding, etc., are trying to do their best in order to reach the modern level of desingning and construction of hospitals. So-called “typical” medical projects of 70-ies and 80-ies continue to be implemented up to now. This is certainly due to inadequate funding, but such economy has at the end rather high cost.

However, the ECP in its classical form has a number of significant drawbacks. One of them is a dependence of treatment modes and electrolyte compositions on the processed material. In addition, aggressive expensive electrolytes that require special technologies for disposal are used for ECP. Electrolytes in ECP often require heating to a temperature of 60–90 °C. Processing at such temperatures causes significant harm to the environment and production personnel. To eliminate the existing disadvantages of the ECP and expand its technological capabilities, a processing method with application of pulsed unipolar and bipolar modes has been proposed. As a result, fundamentally new processes of pulse ECP with a pulse duration of 0.05–20.00 ms have been developed. They provide a reduction of energy costs for the process and high efficiency of polishing in comparison with traditional DC polishing. The rate of smoothing micro-roughness of the treated surface related to the total metal removal is significantly increased. The use of pulse modes in comparison with traditional ECP allows processing in universal electrolytes of simple compositions based on sulfuric and orthophosphoric acids without addition of chromium anhydride. Application of the developed pulse modes, which will provide at low metal removal a significant change in surface roughness, is the most appropriate for the ECP of precise parts, products or parts of small cross-section and rigidity, such as medical devices for minimally invasive surgery, precision engineering parts, etc. The paper presents results of a study for influence of pulsed unipolar and bipolar ECP modes on the surface quality of stainless steel specimens, as well as a comparative analysis of the efficiency of using pulsed ECP modes instead of DC polishing. The technological parameters of ECP using pulsed modes, providing the highest quality surface polishing with high efficiency of micro-roughness smoothing and low energy consumption have been established in the paper.

Thermo-technical installations consuming significant amounts of thermal energy are used in order to intensify precast and reinforced concrete production processes under industrial conditions. Despite significant progress in the study of concrete hardening in accelerated hydration devices, a prominent lack of reliable and cost-effective research and optimization methods of their operation is observed. The methods used in real production processes are mainly based on empirical dependences obtained for specific technological conditions. These methods can not always be applied for other modes and technologies. The present paper develops calculation methods based on fundamental laws that make it possible to obtain functions for evolution of concrete product hydration process. Methods of mathematical modeling permit to develop new ways directed on improvement of modes for heat treatment of concrete products and accelerated hydration technologies. The paper describes a mathematical model for calculating a hardening process of a concrete product that includes a transient three-dimensional heat conductivity equation, a function of internal heat release due to behavior of exothermic reactions of cement hydration and also a system of initial and boundary conditions. A numerical simulation for temperature and hydration coefficient of a concrete product having shape of a 0.1´0.1´0.1 m cube has been performed in the paper. Verification of the non-stationary mathematical model for calculating temperature fields and hydration degree while using experimental data on concrete product strength obtained under industrial conditions. Investigations on hydration degree function of time have shown that experimentally obtained values of compressive strength correlate with hydration coefficient and hydration rate functions of heat treatment time which are calculated on the basis of the proposed non-stationary mathematical model of concrete product hardening. Satisfactory agreement of experimental and calculated data confirms adequacy of the proposed non-stationary mathematical model for calculating temperature fields and hydration degree with accelerated heat treatment of concrete products.

The paper considers a mathematical model which is used to study a composite material similar in structure to asphalt concrete and it takes into account presence of solid particles of different sizes and a soft and plastic binder. The twodimensional method of discrete elements has been applied to investigate destruction of asphalt-concrete samples under uniaxial compression, tension during splitting and compression by the Marshall method. The numerical model takes into account presence of large particles of rubble, asphalt mastic filling rubble pores and sticky (capable of recovering after rupture) communication between rubble particles. The force interaction between various components of the asphalt concrete has been described with the help of elastic repulsion between rubble particles, friction force and force responsible for sticking of particles due to presence of a binder. This model gives a correct fracture pattern for uniaxial compression, stretching during splitting and compression according to the Marshall method and this pattern coincides with the real experiment. It is the correct picture of destruction for three different schemes of material loading which makes it possible to assess the adequacy of the mathematical model which has been used. Basic physico mechanical characteristics of the binder which determine strength and deformability of asphalt concrete have been established in the paper. It has been shown that for an adequate description of physico mechanical characteristics for asphalt concrete it is necessary to study and measure properties of an asphalt binder that is a mixture of bitumen and fine mineral filler which determines parameters of interaction between rubble particles. The numerical experiments serve as a basis and make it possible to propose new laboratory methods for testing a mixture of stone materials and organic binders which are much simpler and, therefore, cheaper than standard tests on asphalt concrete. In addition these tests will more accurately predict behavior of asphalt concrete in real conditions.

The paper analyzes approaches to interpretation of a competitive advantage source in various schools of strategic management. Systematizing concepts and approaches of foreign and national researchers within the framework of this or that strategy school the author of the paper gives preference to the Lakatos concept that various scientific-research programs may coexist and compete simultaneously. Strategic management science does not have any obstacle to compare competing theories in justifying sources of strategic competitive advantage. An internal logic of a theory serves as the basis to compare quality of verbal or formal school models, and consideration of successful / unsuccessful strategies in modern dynamically developing economy makes it possible to obtain data for empirical verification of the models. Purpose of the paper is to evaluate prospects of scientific-research programs proposed by various strategy schools in the context of their approaches to sources of competitive advantage. Evolution of science and practice in strategiс has led to shift in emphasis for understanding a company not as a set of business units but as a set of resources and competencies that contributed to obtaining a dominant position in strategic management of resource-based strategy concept. Search for sources of competitive advantage has been shifted to specific resources which a company possess. Such approach lays a solid foundation for a qualitative analysis of strong and weak points of the organization while forming a sustainable long-term advantage based on the development and protection of company's internal resources. Research of competitive advantage resources from the perspective of the concept of company’s dynamic abilities (modern stage of resource-based concept development) is considered as the most promising one because it is based on endogenous nature of advantage sources. This approach rejects implausible assumptions and emphasizes importance of an entrepreneurial factor.

Copper pipelines are widely used while designing modern heating systems, water and gas supply of residential buildings and these pipelines have a number of advantages in comparison with steel and plastic pipelines. The main reason for limited use of copper pipes is their cost which is practically twice as much as cost of steel pipes, and four times higher than the coat of polypropylene pipes. Modern design standards in Belarus do not contain specific requirements for calculation of copper pipelines. Therefore hydraulic calculation of heating systems has been considered and analyzed on the basis of norms of Russian Federation. The drawback of all theoretical calculations presented in Russian standards is their abstraction from general laws of fluid and gas mechanics. For this reason theoretical foundations of hydraulic calculations for all pipelines have been considered and expressions have been given for determination of pressure loss due to friction and in local loss. Main flow regimes have been considered on the basis of I. Nikuradze’s experiments in order to determine linear losses and dependences for determination of friction coefficient in laminar, transient and turbulent modes have been presented in the paper. Values of local loss coefficient for main pipeline elements are given for calculation of pressure loss and the paper also shows determination of value z with due account of equipment capacity. An analysis of nomograms presented in Russian norms and researches has been carried out; shortcomings have been revealed and the ways directed on their perfection have been found. Nomograms for calculation of specific pressure losses in heating systems and internal gas supply have been constructed on the basis of natural gas and propane with due account of dependences presented in the paper. Nomograms for finding equivalent length of a single local loss have been constructed for calculation of internal gas supply systems.

The world industry is on a threshold of a new development cycle which is characterized by emergence of breakthrough technologies: distributed ledger technology, drone-type devices, 3D printing, virtual reality, Internet of things, augmented reality etc. Due to these technologies fundamental changes will take place in the majority of economic branches. The automotive industry is not an exception. This industry plays one of the key roles in economy in a great number of countries and changes occurring in it lead not only to creation of new products, technical processes but these changes also entail improvement of the industrial base which has been already created. The Republic of Belarus considers an automotive industry as one of key industries for its economy and its efficiency has a high dependency factor pertaining to speed of innovation emergence and implementation that is strategically important aspect of increase in competitiveness both on current sales markets and on potential ones. The paper pays a special attention to two main trends arising in the course of forming a new industrialization: increase in environmentally-friendly fuel systems and digital transformation. Problems of world ecology have exerted a considerable impact on developments in the field of alternative energy sources. Speed of development and promotion of electric vehicles considerably exceed “breakthrough” innovation developments of the past. However a great number of factors can have a significant effect on the future of electric vehicles and two of them are thoroughly considered in the paper: cost of energy (batteries) and price of oil (at the price of about 20 USD for barrel the development rate will considerably decrease). Besides the matter of environmental friendliness the paper pays attention to services of digital transformation. The world has already presented examples pertaining to usage of remote control for dump trucks, telematics etc. Such an approach makes it possible for organizations to optimize substantially an expenditure budget and doing so we increase resource use efficiency. The paper also contains a review of innovations in the automotive industry of the Republic of Belarus: BelGee electric cars, Belkommunmash electrobuses, developments of large industrial equipment.

Reliable forecasting of longevity for solid construction materials, especially for concrete and reinforced concrete is considered as a rather complicated scientific and technical problem which is often described in a great number of research papers. However this problem does not have a reliable analytical solution with the required statistical realization level. The paper contains a brief analysis of modern views pertaining to breakage processes in solid construction materials including concrete and reinforced concrete due to action of force (in particular, on the basis of temporary strength dependence with a static load) and non-force factors comprising as well carbonization and decrease of hydrogen index. Peculiar features concerning strength decrease of construction materials in time due to action of creep processes (plasticity) have been described in the paper. The paper presents two variants for assessment of possible longevity: without initial damage and with available initial defects. According to the first variant distribution of the test specimens of material for longevity corresponds to a lognormal law and in the second variant the distribution follows more complicated law. The paper provides levels of carbonization indices and a hydrogen index when corrosion of steel reinforcement does not occur. The following necessity has been established that is recommended to take into account not only characteristics and specific features in structure of solid construction materials in their strength theory but also statistical regularities because the breakage process represents in itself an integral phenomenon and due to this the final result can change according to random values of available structural defects, test errors and other factors. In this connection probability of their possible combinations has been described with the help of statistical laws. It has been shown that it is desirable to pay due consideration to maximum number of similar factors in order to increase a reliability of probabilistic-statistical methods for calculation of longevity.

The paper is devoted to a challenging problem of ensuring traffic safety on the sections of a highway vertical curve and it provides an analysis for works concerning design, lay-out and organization of a project roadway. A change in vehicle speed has been analyzed depending on the length of a curve and a maximum longitudinal slope of a project roadway. The paper presents statistical data about accidents in the Republic of Belarus for several years on the sections of curves pertaining to project roadways. Comparative analysis of difference between point marks on a parabola is given in the paper and the parabola is inscribed in the fracture of the project roadway while using two methods. The paper presents the following errors: geodetic measurements in excesses while laying out pavement, elevation points along pavement axis while making road pavement. Emergence of centrifugal force causes a change in shearing and holding forces. Excess of the shearing force on the holding one leads to spontaneous sliding in the direction of a shearing force vector. Technical solutions have been developped on the basis of systematic functional and active deterministic method. The solutions are protected by invention patents of the Republic of Belarus and they ensure safety passages of highway sections with this type of curves in a longitudinal profile. While constructing and accepting a road for operation it is necessary to control references of curve elements in the longitudinal profile according to the results of executive surveys and in case of operation it is necessary to inform a driver about a safety speed for a passage through such sections

The paper provides an analysis for production of four-wheel drive dump trucks with an articulated frame and it also describes a practical experience pertaining to operation of dump trucks as mining automotive transport. Technical characteristics for some models of articulated dump trucks manufactured in Russia and Belarus are presented in the paper. The paper gives examples for transportation of run-of-mine ore at enterprises of Russia and abroad. The attention has been focused on specific features concerning organizational, technological and design decision making while introducing and promoting articulated dump trucks. It has been established that articulated dump trucks make it possible to improve an efficiency of mine development during construction period and when ore mining and processing enterprises are put into operation especially in geographically remote and inaccessible areas. The paper proposes technological solutions allowing to expand the scope of articulated dump truck application at mining enterprises while using them for quarry development excavating deep deposits of solid minerals. It has been revealed that reduction in overburden volume can be achieved by transition from a certain depth to lower capacity dump trucks or special dump trucks operating on elevated slopes of roads. The paper shows that one of perspective directions for development of mining technology on kimberlite deposits is an opening of lower quarry horizons by peripheral road tunnels of spiral shape while using articulated dump trucks. The presented technological solutions require further research and design consideration and study and they will allow to ensure resource efficiency and safety of surface mining while extracting minerals at previously uneconomic ore deposits. In order to realize an import substitution program for four-wheel drive dump trucks with an articulated frame it is necessary to carry out marketing research on potential market for machines of this class required for open-pit mining in order to justify prospects for provision of the Russian production market.

The paper considers application and development of information technologies while carrying out project management in construction. Organizational and technological support of works throughout its life cycle exerts an influence on quality and efficiency of successful implementation of the construction project. In order to achieve the project goal it is necessary perfectly to organize and plan works, distribute roles and responsibilities of the project participants, regulate composition and content of the project documentation. While analyzing technical and economic indices of construction organization activity and management systems operating in these organizations, conclusion has been made that market experience in functioning of operational management systems has not been adequately applied in practice of domestic construction organizations. Thus, introduction of integrated management systems for quality, costs, time parameters pertaining to project construction, their resource support will contribute to improvement of economic situation of construction organizations. The solution consists in application of up-to-date information technologies, maximum implementation of computer systems and programs in the sphere of production, creation of application software. It has been shown that it is necessary to develop a software model that provides a possibility comprehensively to apply information technology tools for monitoring progress of construction and installation works, systematization of information technology application that allow to control key parameters of construction and installation works, improvement of system for providing actual information in project implementation process. An example of complex application of software products Primavera P6 Professional R8.3.2 and ArchiCAD 17.0.0 is given in the paper.

Main results of investigations on logistics activities in the Republic of Belarus at year-end 2016 are presented in the paper. The paper identifies and analyzes basic components of this activity on the basis of economic evaluation of indices presented in annual State statistical reporting on logistics and transport and freight forwarding activities of the Republican organizations according to form 1-logistics (Mintrans – Ministry of Transport and Communications of the Republic of Belarus), a report of the Ministry of Transport and Communications of the Republic of Belarus on the results of the implementation of Republican Program for development of logistics systems and transit potential of the Republic of Belarus for the period of 2016–2020, World Bank reports on logistics performance index, some indices of logistics infrastructure position and also results of electronic questionnaire of the largest logistics centers of the Republic of Belarus. Methods of comparative analysis, generalization and economic analysis have been used in the process of research. The analysis has shown that a network of logistics centers with various specialization and forms of property are located and operating in all regions of the Republic of Belarus. Most of them are situated in the Minsk region near the II and IX trans-European transport corridors and in the Brest region near the border with Poland. Structure of the logistics centers includes temporary storage warehouses, customs warehouses, warehouses for general use, container terminals, car parking, customs clearance office, and automotive, railway and other cargo transport facilities. Indices of logistics activity in the Republic of Belarus demonstrate its development in 2016. Storage space of logistics centers and main financial and volumetric indices of logistics activity which are included in the State statistical reporting have been increased during in recent times. These facts testify to the demand for logistics capacity of the Republic of Belarus and its efficient economic and infrastructure development.

A turning method with asymmetric oscillations of cutting tool has been proposed on the basis of the analysis of various methods for chip crushing in the process of structural steel lathe turning and the method makes it possible to ensure a stable crushing of discharge chips and to reduce roughness of the machined surfaces. Asymmetric vibrations are characte- rized by an asymmetry coefficient of the oscillation cycle, their frequency and amplitude and they are additionally transferred to the tool during the turning process. Kinematics of structural steel turning with imposition of directed asymmetric cutting tool oscillations created by a cam system on traditional cutting scheme has been considered in the paper. An equation of tool motion with asymmetric oscillations has been obtained on the basis of Fourier Series. An influence of the oscillatory tool motion amplitude and frequency on the process of discharge chip crushing has been determined in the paper. In order to re-duce a negative influence of the oscillation amplitude on the cutting process and quality of machined surfaces machining must be carried out with its minimum value. In this case it is necessary to ensure an optimum ratio of the tool oscillation frequency to the rotational speed of a workpiece. A formula has been derived for determination of this ratio according to a coefficient of oscillation cycle asymmetry and number of complete oscillation cycles per one revolution of the workpiece. It has been established that a theoretical value of the minimum tool oscillation amplitude is equal to half of the tool feed value per one revolution of the workpiece. If the optimum ratio of the tool oscillation frequency to workpiece rotation frequency has not been observed for chip crushing it is necessary to increase oscillation amplitude that may lead to an increase of roughness on machined surfaces.

Solar systems are actively applied for heat supply of buildings in Europe. Usage of solar energy for heat supply of residential buildings is considered as rather efficient for the Republic of Belarus because total amount of direct and scattered solar radiation entering horizontal surface is equivalent to an average European index for the climate of Belarus. The paper analyzes an existing dependence on determination of solar system efficiency and proposes an amended formula for calculations while designing solar consumption systems and its legitimacy has been experimentally proved. A scheme of an experimental unit with explanations and a brief description for execution of experiments and main results of the completed investigations have been presented in the paper. Experiments have been carried out for solar systems with natural and forced coolant circulation. Attention has been paid to obtaining maximum possible temperature potential of the coolant during operation of the solar system within periods of high and low solar radiation intensity. Recommendations on practical application of solar systems for multi-storey residential buildings houses and mansion-type houses have been given in the paper. The paper presents technological principles of constructing “passive” solar heating devices. A comparison of traditionally applied and proposed alternative solar systems has been made for operational conditions in Belarus. The paper proposes a solar system for hot water supply of multi-storey buildings. The proposed system has found its first realization in the Republic while designing and constructing an energy-efficient demonstration 10-storey residential building in Mogilev within the framework of the UN Development Program project and Global Environment Fund “Improvement of energy efficiency for residential buildings in the Republic of Belarus”

The existing non-destructive testing system of structure concrete is actually orientated on the usage of longitudinal acoustical waves. This is due to simplicity of technical realization for measuring velocity (time) of acoustical pulse propagation in bulk concrete. But a reverse side of simple measuring procedure is a loss of additional information on concrete which is contained in the accepted acoustical signal. Therefore usage of an ultrasonic concrete testing method is limited by assessment of its strength. Joint usage of several wave types, so-called multi-wave testing, allows to refine metrology parameters of the ultrasonic method and to gain more information while determining physical and mechanical properties of concrete in laboratory and in situ conditions. The paper considers testing of elongated concrete elements and structures by an ultrasonic pulsing method on the basis of longitudinal subsurface and Rayleigh waves. It has been proposed to use methodology for time selection of wave components according to amplitude parameter and it has been applied for standard acoustical transformers with considerable reverberation time and not possessing spatial selectivity Basic principle of the proposed methodology is visual (according to oscillogram of the received signal) determination of characteristic time moments which are used for calculation of differential value of a propagation velocity in the Rayleigh wave impulse. The paper presents results pertaining to simulation of acoustical pulse propagation on the basis of 0.15 m and data of concrete ultrasonic in situ testing on measuring bases from 0.25 to 1.75 m. Advantage of large baseline for sonic test is a possibility for execution of a hundred percent inspection for surface of large-sized elements and structures, and so there is no need to make a selective inspection in some control areas as it is stipulated by provided by existing regulations. Responsivity of the Rayleigh wave parameters to near surface concrete defects permits quickly and efficiently to detect crack areas in a reinforced structure. Energy localization of a surface wave in a layer having width λ/2–λ provides a possibility to ignore reinforcement availability under appropriate selection of oscillation frequency. In addition to this, large measuring baseline makes it possible to lower effect of concrete structural inhomogeneity on statistical stability for pulse velocity assessment that ultimately reveals a possibility to register an appearance of concrete acoustical elasticity effect under in situ conditions.

The paper considers reasons of internal air parameter mismatch in warm season of the year for public building premises having large area of translucent structures. The main reason of uncomfortable air environment is an underestimated value of air supply volume due to air exchange calculation according to multiplicity factor or air exchange rate per one person which are determinative values only for cold period and transient conditions. In other words multiplicity factor and air exchange rate do not take into account equipment abundance in modern offices and heat input of the office equipment is rather significant value. The paper contains an analysis and comparison of the existing air exchange rates for the Republic of Belarus, Russian Federation, European countries and USA. Calculation of heat input and air exchange for public building premises during warm season of the year for assimilation of evident heat excess has been made at various orientations of curtain walls. The paper provides structure of heat input into premises. The required rate of air supply volume per one person has been determined on the basis of air exchange and it has been compared with the existing air exchange rate. The required rate averagely exceeds the standard one by 12-fold. But this does not mean that there is necessity to increase the rate in such a way because it entails an increase in capital and operational costs. In this connection the paper reviews variants for improvement of micro-climate in the building premises with large area of translucent structures: automatic regulation of heat transfer in heating appliances during cold period of the year; usage of air conditioning and increase in temperature difference of input and output air during warm period.

The paper reports on peculiar features pertaining to execution of construction works during reconstruction of buildings. Practical experience on replacement of load-bearing structures has been analyzed for illustrative purposes. Attention has been concentrated on peculiarities in respect of organizational and technological solutions resulting from installation of temporary reinforcement structures. This is due to the fact that it is necessary to ensure spatial rigidity and stability of adjacent and existing construction structures of the building. In other words, when certain construction structures are replaced for some period of time the adjacent structures are without any support that ensure position stability for individual structural elements and building as a whole. Such a situation may lead to deformation of structures or their failure. In this regard, works must be performed in accordance with work zones that ensure stability in the adjacent structures. The paper presents examples of practical solutions concerning replacement of load-bearing floor structures and outer portion of a bearing wall in one of the buildings under constraint conditions. In this context when replacing intermediate floor works have been carried to strengthen temporarily reinforced concrete columns. Spacer steel beams providing column stability from plane have been used for this purpose. While making partial dismantling of the wall a variant presupposing installation of temporary vertical bearing structure in the form of a portal has been used in the paper. The given structure has been bearing loads from floor slab up to completion of re-bricking of bearing wall portion and arrangement of other structures in accordance with design solutions. The presented organizational and technological solutions will be useful for builders and designers while making development of design and technological documentation for reconstruction of buildings.

The paper presents results of investigations on the process pertaining to interaction of a driving wheel with ground surface and describes methodology for optimization of backbone parameters. The mentioned process has some specific differences in comparison with the process of wheel rolling along hard surface. Ground surface is represented by mixture of sandy and clay particles with plant residues and it has a number of physical and mechanical properties. The main of these properties is resistance of soil against compression and displacement. Compression process determines a track depth and resistance to motion and displacement process determines wheel gripping property and its tangential traction force. While executing the investigations laws of compression and displacement proposed by Prof.V. V. Katsygin as the most adequate reflection of actual processes have been used in the paper. Motion of the driving wheel along ground surface is accompanied by its slipping. It has been determined that the maximum wheel traction force is formed not with 100% slipping as it was supposed until present but the value has been obtained at 45–60 % slipping according to soil category. The developed integral equations with due account of the aspect make it possible to calculate road hold characteristics of driving wheels of the designed wheel tractor and evaluate its traction, speed and economic characteristics. Methodology has been developed for optimization of backbone parameters of wheeled running gear in the designed tractor such as design mass and adhesion weight, width, diameter and air pressure in a tire. The proposed methodology has been introduced in designing practice of wheeled tractors at OJSC “Minsk Tractor Works”.

The paper presents results pertaining to investigations of traffic conditions and intensity of traffic and pedestrian flows, calculations on loading level of objects located in the Makayonka Street, Minsk. The objects constitute transport regional development which presupposes reconstruction of regional arterial street with due account of infrastructure improvement, residential construction and construction of multi-purpose complex with shopping, entertainment, wellness and business centers. In addition to this it is planned to construct a two-level underground parking, a two-level interchange at intersection of the Filimonova Street and Nezavisimosty Avenue due to an increase of traffic load at adjacent neighboring street and road network. An analysis on the current traffic management and calculation for distribution of the existing and prospective traffic load levels after implementation of appropriate measures to improve quality as a whole and road safety as well has been carried out in the paper. Determination of loading levels for a street and road network has been carried out while taking into account an intensity of traffic flows in order to evaluate various options for road traffic organization. Variants for planning of road junctions, road traffic organization and traffic signalization (including coordinated passing of transport facilities) have been developed in the paper. All this will contribute to improvement of quality and road safety in the investigated street with due consideration of further development of the region and overbuilding of the existing housing system in the Makayonka Streets and increase of its transport importance in the Minsk street and road network.

Literary analysis has shown that the majority of researchers are using classical efficiency criteria for construction of an optimization model for production process: profit maximization; cost minimization; maximization of commercial product output; minimization of back-log for product demand; minimization of total time consumption due to production change. The paper proposes to use an index of added value as an efficiency criterion because it combines economic and social interests of all main interested subjects of the business activity: national government, property owners, employees, investors. The following types of added value have been considered in the paper: joint-stock, market, monetary, economic, notional (gross), net, real. The paper makes suggestion to use an index of real value added as an efficiency criterion. Such approach permits to bring notional added value in comparable variant because added value can be increased not only due to efficiency improvement of enterprise activity but also due to environmental factors – excess in rate of export price increases over rate of import growth. An analysis of methods for calculation of real value added has been made on a country-by-country basis (extrapolation, simple and double deflation). A method of double deflation has been selected on the basis of the executed analysis and it is counted according to the Laspeyires, Paasche, Fischer indices. A conclusion has been made that the used expressions do not take into account fully economic peculiarities of the Republic of Belarus: they are considered as inappropriate in the case when product cost is differentiated according to marketing outlets; they do not take account of difference in rate of several currencies and such approach is reflected in export price of a released product and import price for raw material, supplies and component parts. Taking this into consideration expressions for calculation of real value added have been specified in the paper.

Pollution of an atmosphere due to hazardous substances emissions deteriorates ecological environment in the world. Exhaust gases of diesel engines are considered as one of the main environmental pollutants. At the moment it is not possible to determine rate and limits of threshold level of air pollution which do not affect human health. The paper considers current issues pertaining to regulation and control over dispersed particles. The most convenient measuring methods for investigations are those which provide the opportunity to obtain immediate results. However, from the legislative point of view, a gravimetric investigation method is a legitimate one which requires compliance with certain procedures of adjustments and calculations. The method presupposes availability of complicated system for sample dilution and its adjustment must include temperature and kinetic parameters of the measured flow. In order to ensure measuring accuracy and results reproducibility filter loading should be in a regulated range and dilution parameters should be chosen according to not only engine type but also according to its emissions rate. Methods for evaluation of a hot exhaust gas sample is characterized by higher response and the results correlate with indices of combustion efficiency. However, such approach does not account for a number of processes that take place during gas cooling in the environment. Therefore, in this case, measuring results are to be evaluated within certain boundary conditions with respect to the object of investigations. Difficulty in achievement of modern ecologocal standards is substantiated by complicated fractional composition and multiple stage process in formation of hazardous components. The paper presents calculated dependences between particles and smokiness and contains a comparative analysis. Methods for measurement and investigations of dispersed particles have analyzed on the basis of the results obtainesd during engine tests at various values of fuel supply parameters (injection pressure and timing advance angle of fuel injection).

The paper considers new methodologies pertaining to on-board diagnosis of wear-out rate for friction linings of a clutch driven disk and friction discs of a hydraulic press clutch of transmission gear boxes which are based on physical process that uses friction work as an integrated indicator. A new methodology in determination of life-span rate for engine oil has been developed in the paper. The paper presents block schematic diagrams for on-board monitoring of technical state for power units of wheeled and tracked vehicles. Usage of friction work as an integrated indicator for determination of wear-out rate for friction linings of clutch driven disk and friction discs of a haydraulic press clutch makes it possible timely at any operational period of wheeled and tracked vehicles to determine their residual operation life and forecast their replacement.While taking volume of the used fuel for determination of engine oil life-span rate it permits quickly and effectively at any operational period of wheeled and tracked vehicles to determine residual useful life of the engine oil and also forecast its replacement.

The paper contains a theoretical underpinning on creation of ultrasonic vibration concentrators based on annular elastic elements with non-circular (ellipse-like) eccentric shape of internal contour. Shape of internal contour in polar coordinates is described by Fourier series relative to angular coordinate that consists of a constant term and first and second harmonics. An effect of geometric parameters of the concentrator on amplification factor and natural vibration frequencies has been investigated with the help of a finite element method. The paper reveals the possibility to control an amplification factor of annular concentrators while varying eccentricity of internal contour and mean value of cross-section thickness. The amplification factor satisfies a condition K < N, where N is thickness ratio of amplifier input and output sections, and it is decreasing with increase of vibration mode order. The similar condition has been satisfied for conical bar concentrator with the difference that in the case of bar concentrators an amplification is ensured due to variation of diameter and N will represent ratio of diameters. It has been proved that modification of internal contour shape makes it possible to carry out a wide-band tuning of natural frequencies of concentrator vibrations without alteration of its overall dimensions and substantial change of amplification factor, which is important for frequency matching of the concentrator and ultrasonic vibratory system. Advantages of the proposed concentrators include simplicity of design and manufacturing, small overall dimensions, possibility for natural frequency tuning by means of static load variation. The developed concentrators can find their application in ultrasonic devices and instruments for technological and medical purposes.

The paper presents modern approaches to processing of images obtained with the help of industrial equipment. Usage of pixel modification in small neighborhoods, application of uniform image processing while changing brightness level, possibilities for combination of several images, threshold image processing have been described in the paper. While processing a number of images on a metal structure containing micro-cracks and being under strain difference between two such images have been determined in the paper. The metal structure represents a contour specifying the difference in images. An analysis of the contour makes it possible to determine initial direction of crack propagation in the metal. A threshold binarization value has been determined while processing the image having a field of medium intensity which are disappearing in the process of simple binarization and merging with the background due to rather small drop between the edges. In this regard an algorithm of a balanced threshold histogram clipping has been selected and it is based on the following approach: two different histogram fractions are “weighed” and if one of the fractions “outweighs” then last column of the histogram fraction is removed and the procedure is repeated again. When there is rather high threshold value a contour break (disappearance of informative pixels) may occur, and when there is a low threshold value – a noise (non-informative pixels) may appear. The paper shows implementation of an algorithm for location of contact pads on image of semiconductor crystal. Algorithms for morphological processing of production prototype images have been obtained in the paper and these algorithms permit to detect defects on the surface of semiconductors, to carry out filtration, threshold binarization that presupposes application of an algorithm of a balanced threshold histogram clipping. The developed approaches can be used to highlight contours on the surface images of mechanical engineering products and prepare them as production prototype images in accordance with enterprise documentation. Such approach makes it possible to remove noise on radiographs without introduction of additional distortions in the processed image; highlight defects of welded joints on the images.

Virtual testing of portal machine tool has been carried out with the help of finite elements method (FEM). Static, modal and harmonic analyses have been made for a heavy planer. The paper reveals influence of concrete filler on machine tool dynamic flexibility. A peculiar feature of the simulation is concrete filling of a high-level transverse beam. Such approach oes look a typical one for machine-tool industry. Concrete has been considered as generalized material in two variants. It has been established that concrete application provides approximately 3-fold increase in machine tool rigidity per each coordinate. In this regard it is necessary to arrange closure of rigidity contour by filling all the cavities inside of the portal. Modal FEA makes it possible to determine that concrete increases comparatively weakly (1.3–1.4-fold) frequencies of resonance modes. Frequency of the lowest mode rises only from 30.25 to 42.86 Hz. The following most active whole-machine eigenmodes have been revealed in the paper: “Portal pecking”, “Parallelogram” and “Traverse pecking”. In order to restrain the last mode it is necessary to carry out concrete filling of the traverse, in particular. Frequency-response characteristics and curves of dynamic rigidity for a spindle have been plotted for 0–150 Hz interval while using harmonic FEM. It has been determined that concrete increases dynamic machine tool rigidity by 2.5–3.5-fold. The effect is obtained even in the case when weakly damping concrete (2 %) is used. This is due to distribution of vibrational energy flow along concrete and along cast iron as well. Thus energy density and vibration amplitudes must decrease. The paper shows acceptability for internal reinforcement of high-level machine tool parts (for example, portal traverses) and fillers are applied for this purpose. Traverse weighting is compensated by additional torsional, shear and bending rigidity. The machine tool obtains the possibility for rough intermittent cutting even at resonance frequencies. Complete concrete filling of portal cavities is definitely a positive action for static and dynamic properties of the machine tool.

Regulation of a river flow makes it possible to meet contradictive requirements of various participants of water resources systems. In recent years the main participants of water resources systems pay a lot of attention to flood prevention in Vietnam and water floods are rather typical for river basins in the South-West of Belarus. Due to such circumstances it looks rather reasonable to create water storage reservoirs. However, degree of flow regulation that is value of the reservoir useful capacity must have a techno-economic justification with due account of river basin specific features. The paper considers particularities of small rivers in pre-mountainous regions of Vietnam. It is expected that the main water use occurs during irrigation processes. For this reason the requirements of other water resources systems participants (especially requirements on flood protection) have come into account in a minimum way. The paper proposes a criterion for optimization of water resources systems parameters and in this case the main participants are irrigation and flood prevention. The criterion reflects minimum regulated volume of river flow per unit of irrigated area while observing restrictions pertaining to flood control, water supply, pond fish farms, water power engineering and environmental protection. Application of mathematical models on the basis of economic criteria for optimization of the water resources systems parameters is possible rather rare due to absence, shortage or poor accuracy in initial data.

The paper shows how to determine dimensions of stationary horizontal (canopies) and vertical (ribs) shading devices in order to prevent penetration of normal beam solar radiation into the buildings during warm season of the year. While analyzing formulae for insolation rate equations for determination of dimensions of canopies and ribs which are perpendicular and inclined to the plane of intensively irradiated fenestrations orientated to the South, South-East, South-West, East and West have been obtained in the paper. Sloping canopies have the smallest dimensions. What is more, an angle of slope with regard to opening plane must correspond to elevation of sun station at an hour when there is a maximum specific heat flow rate of normal beam solar radiation. The paper considers an influence of canopies and ribs on transmission of diffuse solar radiation which along with normal beam solar radiation serves for creation of natural illumination. As follows from the analysis of formulae it is possible to make a conclusion about an inefficiency of vertical shading elements due to large rib dimensions and decrease in transmission of diffuse solar radiation. Minimum distances from fenestration reveal to the canopy have been determined for various orientations proceeding from the position that the opening must be maximally illuminated by normal beam solar radiation during the cold season of a year in order to reduce heat inputs for building heating. On the basis of dependence analysis we have come to a conclusion that it is appropriate to design stationary shading devices for fenestrations orientated only to the South and they must be sloping canopies. It is necessary to select glazing with a small index of solar factor for openings orientated to other corners of the Earth and reduction of solar radiation heat inputs.

The paper analyzes main reasons that have led to closure of a number of industrial enterprises on the territory of the Republic of Belarus and in the majority of former Soviet Union countries. An analysis of constructive decisions and range of bearing and enclosing structures for non-operational industrial buildings and facilities has been carried out in the paper. The analysis has made it possible to draw a conclusion that the overwhelming majority of the buildings and facilities were constructed using prefabricated and cast-in-situ reinforced concrete structures. Taking into account the facts that substantially all non-operational industrial buildings and facilities are located in industrial zones being rather far from residential housing area and having developed infrastructure (highways, railway lines, communication network etc.) and expenses on infrastructure development usually exceed the cost of newly built industrial buildings and facilities some findings have been given on expediency pertaining to usage of existing industrial zones. The main problem has been defined in the paper and its solution will permit to use again existing industrial zones with non-operational industrial facilities which are located there. With due account for the executed analysis of standard operating procedures on liquidation of industrial buildings an expediency has been revealed that presupposes demolition of facilities with the help of mechanical breakdown. An economic efficiency on application of mechanical demolition method for industrial buildings constructed using prefabricated and cast-in-situ structures has been illustrated in Work Execution Plan on liquidation of industrial buildings in the workshop which has been involved in lime production at JSC “Berezovsky Industrial Complex of Silicate Products”. The proposed technology for mechanical demolition of reinforced concrete structures is based on application of a caterpillar excavating machine of Doosan S340LC-VSDM model. Its application permits to ensure complete safety conditions while executing works.

Мerging traffic junctions on high-class roads are considered as bottlenecks in the network and quality of their operation determines a probability for formation of traffic congestions. Investigations on congestion situations in the merging zones of ramp and freeway traffic flows have demonstrated that queuing ramp traffic flow leads to formation of so called “turbulence” effect due to re-arrangement of transport facilities and reduction in their speed on main road direction. Having high queuing traffic flow on main road the “turbulence” component can result in formation of an impact blow in the main traffic flow. It has been proved that an impact of the ramp traffic flow on congestion probability is higher in comparison with main road traffic flow. The paper makes it possible to establish that some transport facilities moving along a high-way simul taneously occupy two lanes in the merging traffic zones and they reduce capacity of the used road section. It is necessary to take into account this specific feature and it is necessary to pay attention to it in the zones of “turbulence” effect formation. The paper presents main approaches, methodology, principles and stages required for access control of high-class roads which are directed on higher quality of their operation including improvement of road traffic safety. The paper proposes a methodоlogy that allows to evaluate and optimize ramp control in the context of a transport queue length minimization at adjoining ramps for the purposes of probability reduction in transport congestion.

The paper contains definitions for a process and a methodology for restoration of parts on the basis of the analysis of the known methods and their selection. Geometric parameters and operational properties that should be provided for restoration of parts have been determined in the paper. A process for selection of the required method for restoration parts has been improved and it makes it possible to synthesize an optimal process of the restoration according to a criterion of industrial resource consumption with due account of quality, productivity and security limits. A justification on measures that meet the required limits has been presented in the paper. The paper shows a direction of technical solutions that ensure complete use of residual life of repair fund parts. These solutions can be achieved through close application of all repair sizes of work-pieces with revision of their values, uniform removal of the allowance while cutting the work-pieces at optimum locating, application of coating processes only in technically justified cases, application of straightening with thermal fixing of its results or all-around compression of deformable elements. The paper proposes to limit a number of overhauls for the units together with restoration of basic and fundamental parts by two repairs for the whole period of their lifetime. Number of shaft journal building-up should be limited by one building-up operation throughout the whole life cycle of the part with the purpose to preserve its length within the prescribed limits. It has been recommended to expand an application area of volumetric plastic deformation of material in the form of thermoplastic distribution or reduction of repair work-pieces representing class of rotation bodies with holes that ensures an allowance to machine external and internal surfaces for nominal dimensions without coating. A structure of the coating material with fine inclusions of carbides or nitrides of metals and preferred orientation of structural components perpendicular to the restored surface under the influence of heat removal has been established in the paper. Due to surface plastic deformation the structure orientates fiber axis tangentially in the direction of relative sliding that inhibits growth of fatigue radially oriented cracks.

Sintered friction materials are widely used in friction units of automotive vehicles and special purpose vehicles. The main purpose is to transmit torque to the actuator. The development of the technology market requires the development and use of new units. At the same time, the creation of new materials is required, which also applies to sintered friction materials. This group of materials is characterized by a high service life, efficiency of torque transmission, as well as the ability to restore performance in case of violation of operating modes. One of the most significant parameters characterizing a sintered friction material is wear resistance. In most cases, it determines not only the resource of the unit itself, but the entire machine as a whole. A special place is occupied by brake units, which also use friction materials. The increased wear resistance of the friction material contributes to a decrease in the efficiency and service life of the brake system. Evaluation of the wear resistance of a friction material for the given operational parameters is a very long and costly process. The development of methodology and methods for accelerating the assessment of wear resistance is an important scientific and practical task. The paper presents the results of using artificial neural networks to predict the service life of a composite friction material based on copper on the sliding speed, pressure on the material and the amount of lubricant supplied to the friction zone. An artificial neural network has been trained using an array of experimental data for the FM-15 friction material. The training results have shown high accuracy, correctness of the proposed and implemented network architecture. The developed software has demonstrated its efficiency and the possibility of using it in calculations to determine the wear of a composite friction material.

The paper presents the results of the development and implementation of the technology of self-compacting heavy structural concrete and the technology of concreting with its use of the largest foundation slab in Belarus (concrete volume ~9100 m3) of a high-rise building at the facility “Construction of a multifunctional complex in Minsk within the boundaries of Filimonova Street – Avenue Nezavisimosty – Makayonka Street”. The results of research are shown, which ensured the production of self-compacting concrete of class C35/45 with water resistance up to W20 (with the required W12 according to the project) from concrete mixtures of the maximum cone expansion of the PK6 (RK6) grade for three zones of the foundation slab different in degree of reinforcement: lower, middle and upper, with a total structure height of 3.5 m and plan dimensions ~(83´34) m. The technology of continuous (seamless) concreting has been developed and implemented, which made it possible to lay ~9100 m3 of concrete into the structure without defects within 42 hours of continuous operation, and a system of technological measures that prevented temperature cracking in concrete. The homogeneity of the physical and mechanical properties of concrete, confirmed by control tests, is ensured due to the uniform supply of the concrete mixture (from six concrete pumps at the same time) in layers 200–300 mm high with a distance between the supply points of about 5–6 m and the vertical arrangement of the “trunks” of the concrete pipes during delivery of concrete to each point, as well as the fact that the time for feeding the next volume of concrete was significantly less than the setting time of the previously laid concrete (with a total concreting speed £0.1 m/h). Standardized and original test methods for concrete mixtures, hardening kinetics and properties of hardened concrete have been used during the development, research and implementation of the project. Control tests of physical and mechanical properties and characteristics of concrete, carried out at BNTU together with authorized organizations controlling the progress of construction, as well as in independent (third-party) organizations, have confirmed their compliance with the design requirements.

Light self-destruction-degradation of the second type has been observed in samples of semiconductor lasers with electronic energy pumping with high optical homogeneity and good quality of surface treatment. In these samples, damage appeared in the form of cords perpendicular to the ends of the resonator. According to the current understanding of the passage of powerful light streams through various media, the emergence of narrow light channels is due to the phenomenon of self-focusing. It refers to the fundamental physical mechanisms of propagation of laser radiation and is caused by nonlinear phenomena arising in a medium under the influence of high-power laser radiation. The physical reason for self-focusing is an increase in the refractive index n in a strong light field. Thermal self-focusing is the most probable cause of radiation redistribution in the active region of the crystal. However, it is possible that in the initial stage of the appearance of light channels a certain role is played by the growth of the intensity of radiation in certain sections of the crystal because of the instability of generation or small fluctuations in the pump current density. Then the process acquires an avalanche character, since the localization of the ray in the channel increases the density of light radiation which can lead to overheating of the substance and the activation of the thermal self-focusing mechanism. The experiments performed in this paper have shown that optically homogeneous crystals possess maximum resistance to degradation processes. In them, the critical power of light destruction is determined by the self-focusing threshold of radiation in a material. Since the nonlinear addition to the refractive index Δn = n2E2 at the self-focusing threshold is determined by the change in the concentration of non-equilibrium carriers ΔN(E2), the value of the maximum fluctuation DΔNmax itself is proportional to the value of the non-equilibrium carrier concentration at the generation threshold ΔNpores and the relative excess of the generation threshold J = (j – jn)/jn. Thus, a low threshold concentration of non-equilibrium carriers is one of the conditions for increasing material resistance to degradation processes. In doped crystals ΔNpores is less than in pure materials. This, perhaps, explains the rather higher value of Pcritial in the optimally doped homogeneous n-GaAs. Smaller values of Pcritial in p-type samples doped with zinc can be associated not only with the inhomogeneity of these crystals, but also with large generation thresholds. In addition, the cross section for absorption of radiation by holes is about 3–4 times larger than by electrons, which can also reduce the self-destruction threshold of lasers. At Т = 300 K, the lasing thresholds are higher that naturally reduces the value of the self-focusing threshold.

The purpose of this work is to consider the requirements for emissions of harmful substances of diesel engines by selecting design and adjustment parameters that determine the organization of the workflow, and the exhaust gas cleaning system, taking into account the reduction of fuel consumption. Design elements and geometric characteristics of structures for a turbocharged diesel engine of Д-245 series produced by JSC HMC Minsk Motor Plant (4ЧН11/12.5) with a capacity of 90 kW equipped with an electronically controlled battery fuel injection have been developed: exhaust gas recirculation along the high pressure circuit, shape and dimensions of the combustion chamber, the number and angular arrangement of the nozzle openings in a nozzle atomizer, and inlet channels of the cylinder head. Methods for organizing a workflow are proposed that take into account the shape of the indicator diagrams and affect the emissions of nitrogen oxides and dispersed particles differently. Their implementation allows us to determine the boundary ranges of changes in the control parameters of the fuel supply and exhaust gas recirculation systems when determining the area of minimizing the specific effective fuel consumption and the range of studies for the environmental performance of a diesel engine. The paper presents results of the study on the ways to meet the requirements for emissions of harmful substances, obtained by considering options for the organization of working processes, taking into account the reduction in specific effective fuel consumption, changes in the average temperature of the exhaust gases and diesel equipment. To evaluate these methods, the following indicators have been identified: changes in specific fuel consumption and average temperature of the toxicity cycle relative to the base cycle, the necessary degree of conversion of the purification system for dispersed particles and NOx. Recommendations are given on choosing a diesel engine to meet Stage 4 emission standards for nitrogen oxides and dispersed particles.

Currently, due to the increase in the average speed of vehicles to ensure their visibility, the luminous intensity of their lightning equipment is constantly increasing, that can lead to blindness of other road users, especially at night. On the other hand, if you do not increase the luminous intensity if lanterns, a vehicle will not be noticeable in difficult road conditions (fog, rain, dust) and it can cause an accident. To eliminate this contradiction, a fundamentally new modular design of the adaptive rear combined vehicle light with non-replaceable light sources based on single powerful light emitting diodes and effective secondary optics of large diameter has been developed in the paper. The design provides for the use of an integrated microcontroller to control luminous intensity of its lights, depending on the conditions of external illumination, braking dynamics of a car and surface condition of a lamp diffuser with the possibility of transmitting data via a CAN-bus. Thanks to the built-in microcontroller, the developed flashlight is suitable for installation on vehicles without an on-board computer. These properties allow the flashlight to ensure visibility of a vehicle, and to avoid blinding the remaining road users. The design of the adaptive lamp is small in thickness (up to 40 mm), high luminous efficiency (at least 85 %) and reliability. The conducted lightning tests have shown that the developed lamp fully complies with UN Regulation No 6, 7, 23, 38, 48. The design has been compared with existing analogues of foreign production, which showed that such a lamp consumes less energy (30 %) and has a lower probability of failure due to the use of high-power LEDs used as a light source.

Catastrophic degradation takes place in case of reaching critical values of laser radiation density power in semiconductor lasers with electronically pumped energy made from single crystals of some compounds. It has been accompanied by mechanical destruction of the surface at resonator ends, an irreversible decrease in radiation power and an increase in generation threshold. Moreover, during the catastrophic degradation of semiconductor lasers under the action of intrinsic radiation, significant changes in the crystal structure occur within the single crystal: dislocation density reaches a value more 1012–1015 cm–2. It has been shown that initial density of dislocations and critical power density of the intrinsic radiation are inversely proportional. Thus, the degradation process of semiconductor lasers is directly related to generation and multiplication of dislocations during laser operation. Mechanical destruction of a crystal lattice occurs at critical values of laser radiation power and dislocation density. To clarify the proposed mechanism for the degradation of semiconductor lasers, it is necessary to take into account an effect of dislocations on optical properties of semiconductors. Typically, this effect is considered as follows: dislocations cause an appearance of a local deformation field and, in addition, form space-charge regions that surround a dislocation core in the form of a charged tube. The paper proposes a model of the phenomenon under study: large stresses arise in the dislocation core, leading to a displacement of individual atoms and deformation of the crystal lattice. Lattice deformation in the dislocation core leads to a local change in the width of a forbidden band. This change value is about 10–2 eV for a screw dislocation and 10–1 eV for a boundary dislocation. The mechanism of this change is that aforementioned deformation leads to a multiple rupture of electronic bonds and an increase in the electron concentration in the dislocation core to approximately value 1018 cm–3. The developed analytical model of the degradation mechanism allows to perform selection of a semiconductor and estimation of a laser operating mode under conditions of increased radiation power.

For any company that sells its products in the networks of city stores, the urgent issue is the optimal delivery of their goods. During routing it is necessary to take into account many restrictions caused by specific conditions of transportation process in the city: number of cargoes, nature of cargoes, delivery time, structure of fleet and its presence, work time of enterprises for load matching, drivers’ working hours, loading capacity, road congestion etc. These days, the process of efficient manual routing is difficult because of many restrictions and delivery points wherein it is almost impossible to take into account the road congestion for specific routes. Today's companies are increasingly interested in outsourcing. One of the options for routes planning for enterprises is to use special software products that allow to plan optimal routes according to the chosen criteria and under specific conditions. The process of formation of routes using the Ant Logistics service, based on the Ant Colony optimization algorithm are analysed in the paper. Comparing the two options of forming routes to serve one of the largest retail chains in Kharkiv with the application of Ant Logistics service, it has been elucidated that the application of Ant Colony algorithm is more optimal than the Clarke-Wright algorithm based on delivery routes indicators.

The paper is devoted to identifying patterns of activity of Russian universities in the national innovation ecosystem. Decisions on the development of innovative activity, effective commercialization and implementation of scientific developments are substantiated in strategic documents of state development. In fact the level of innovative security of a country, the state of protection of national interests of the state from internal and external threats arising from the conditions of innovative development, depends to a large extent on the success of the implementation of scientific and development projects. The leading higher education institutions are entrusted with the task of becoming centers of regional innovation ecosystems, transforming universities into active participants of socio-economic and innovative development. Official statistics on national research universities of the Russian Federation have been used in order to identify patterns of the activity of higher education institutions in this area. An analysis of the changes in the analyzed indicators has made it possible to single out universities that implement the most promising models of scientific activity management in terms of world experience. These are primarily universities for which there is a positive relative increase in indicators of total R&D, the share of extra-budgetary funds in university income from R&D, and the share of income from R&D in total income. It has been established that the current stage of development of universities is characterized by the presence of both competitive advantages and challenges that form the features of their modernization. The response to the challenges should be the creation of a business model of the University 4.0 activity which includes new technologies, products and services that are in demand in the country.

Growing vehicle variant diversity, legal requirements to reduce fleet CO2 emissions and innovations in the area of drive train technologies, coupled with the increasing pressure to cut costs, pose new challenges for parties in the automotive sector. An implementation of optimized development and production processes supports the effective handling of these challenges. One important aspect includes engineering efficiency improvement by optimizing the entire automotive bodywork development process and the involved data management. Research activities focus on the data exchange processes between design, simulation and production engineering within various CAx environments. This concerns constantly changing boundary conditions and requirements in the area of automotive body development, including but not limited to the introduction of new materials and material combinations and new types of joining technologies. From the viewpoint of an automotive engineering supplier, additional challenges caused by different customer-related development environments have to be considered. To overcome these challenges, various data exchange strategies between OEMs (Original Equipment Manufacturer), automotive suppliers and the use of different data management tools need to be investigated. In this context, the paper presents an approach of an optimized data exchange process of CAD-based data between different CAD (Computer-Aided Design) and CAM (Computer-Aided Manufacturing) environments that supports the entire body development, including data provision for manufacturing engineering. In addition, an optimization of data exchange processes saves development costs and improves the product quality.

In the XXI century, when environmental awareness is growing and the impact of human activity on the planet is more and more noticeable, striving to minimize energy consumption seems to be a necessary direction in the development of technology. This development cannot take place without an initial understanding and describing the relationships influencing specific technologies. It also needs empirical verification of assumed theories. Modern trams play an important role in the functioning of urban transport. Being one of the oldest modes of environmentally friendly transport, in European capitals they are currently perceived as one of the most convenient means of transport. This is due, among other things, to the high velocity of transport along the route. The energy consumed by trams indirectly depends on the driving characteristics, i. e. speed, acceleration and stops on the route, which are also caused by stopping at traffic light controlled junctions. This paper presents the results of an experiment showing the change in the level of electric energy consumption depending on the applied method of traffic light control. This article presents the conditions influencing the power consumption in trams, describes the possible strategies of traffic lights control and their consequences for other traffic participants. The research was carried out in real conditions in everyday traffic, measuring the level of electricity consumption in case of both fixed-time and actuated signaling with full priority for trams. On the examined section there were both modern asynchronous-drive as well as traditional resistor-drive vehicles. The conclusions drawn from the survey confirm the validity of introducing modern solutions and may be useful for estimating investment costs.

The use of information technologies and, in particular, information training systems increases capacity of both a teacher and a student to achieve their goals in an educational process, taking into account individual characteristics of each and providing opportunities for continuing education. The paper proposes and considers a new automated learning management system, called CATS (Care About the Students). The proposed system covers all components of the educational process, allows to conduct an electronic journal of visiting and defending laboratory works, distribute topics and monitor progress of course and diploma projects (creating automatically task sheets with subsequent export to MS Word editor). The CATS LMS makes it possible to test students’ knowledge in control and self-education modes, to form electronic educational and methodical complexes, to inform students about topics of lecture and practical classes with the possibility of downloading relevant materials, to provide educational content in SCORM format, developed by teachers around the world. Working in the CATS system, it is possible to exchange messages with students and teachers, to monitor progress and process of studying in respect of the proposed material by students, to check accomplished assignments of students for plagiarism. The system under consideration also takes into account specificity of training at a technical higher education institution, providing for work with an integrated project management system and ability to submit bugs. The CATS LMS has been implemented as a web application using modern technologies and it is available in the local network within the whole university at [172.16.11.72:2020].