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The paper describes a technique for assessing the thermally stressed state of a concrete massif of a foundation slab made of a self-compacting concrete mixture. The proposed method consists in a preliminary calculation of temperature fields in hardening concrete. The objects of research have been self-compacting concrete mix and structural concrete in the structure mass. The choice of materials for the preparation of a concrete mixture is given and substantiated. The composition of self-compacting concrete has been used to assess the thermally stressed state. A binder with a reduced exotherm has been used in order to reduce the self-heating of concrete. Studies have been carried out to assess the specific heat release of the recommended cement depending on the initial water-cement ratio. The effect of a chemical additive on the rate and magnitude of the specific heat release of cement has been studied. The paper presents the main theoretical provisions and an algorithm for calculating the thermal stress state of a concrete massif. The finite difference method has been used to calculate the expected temperatures and their distribution in the structure mass, and the temperature stresses in the sections of the concrete mass have been calculated to assess the thermally stressed state. The performed calculations of the temperature fields have made it possible to estimate the maximum possible temperatures and temperature differences over the sections of the concrete massif depending on the initial temperature of the concrete mixture and the average daily temperature of the outside air. Analysis of the temperature distribution has revealed the most dangerous sections of the concrete mass. An assessment of the thermal stress state of the concrete mass has been made on the basis of the results pertaining to calculation of temperature fields. The calculation of temperature stresses in the most dangerous sections of the concrete massif has been performed. It is shown that the calculated value of the temperature stress can serve as a characteristic of the thermally stressed state of the concrete mass. The formation of temperature cracks in a concrete mass is possible when the calculated value of the temperature stress exceeds the actual tensile strength of concrete. Comparison of the calculated and actual values of temperatures in the sections of the foundation slab has made it possible to conclude that the calculations of the temperature fields and, as a consequence, possible temperature deformations are correct.

A schematic and structural solution of regenerative-utilization heat use in centralized heat supply systems was previously proposed in order to increase the efficiency of operation of heating networks located in non-passable channels. The impossibility of creating a full-scale experimental setup covering the required range of factors and the area of their change, the complexity of a passive experiment on existing heating mains led to the need to develop a virtual model based on the ANSYS sofware package. A six-factor experiment has been carried out on this virtual model. Regression equations have been obtained to determine the pressure required to provide air purging of the channel, as well as heat exchange with pipelines of direct and return network water located in the channel, and heat exchange with soil around the channel. In addition, a regression relationship has been derived to find the integral heat flux from the listed washed surfaces to the air flow. The transition from dimensionless to natural factors has been made in the paper. The most significant factors are identified with the help of Pareto cards. The obtained dependencies have been verified in Part 1 of the paper. The adequacy of the obtained regression equations has been determined using standard statistical estimation methods based on the calculated values of the Fisher’s, Student’s and other criteria. The response surfaces are presented and analyzed using two dimensional sections for a number of factor values at fixed values of one and a change in two most characteristic, physically significant for a given response function. They have been validated on the basis of the analysis of regression dependencies. The obtained regression equations cover almost the entire range of possible diameters of heating mains, which makes it possible to use them in the development of energy-saving projects.

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''.

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.

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.

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 deals with a workflow of a proportional pressure modulator equipped with a linear electric motor of electromagnetic type (LEMET). A schematic diagram consisting of a power supply and control system has been constructed to determine the performance of LEMET. The power supply system is a self-contained half-bridge inverter. The converter input is supplied with 12 V DC voltage. The motor phase is powered by an inverter which includes transistor switches and diodes. The control system of the autonomous inverter consists of two channels – a current limiting channel and a linear transfer channel. The study is based on the results of numerical and simulation modeling of LEMET workflows. Numerical simulation is performed and investigated by a finite element method in the FEMM environment. Geometry of the LEMET model lies in the region of air with an electromagnetic permeability of 1. An initial radius of the grid generation for the working gap area is 0.5 mm, while for other areas an adaptive generation method has been applied. In order to determine a continuous power function at any point within a current variation interval i and a displacement x current linkage and electromagnetic force functions have been approximated by polynomials use of the Curve Fitting application. The simulation LEMET model of a proportional modulator has been built in the MatLab Simulink environment. The implicit Runge-Kutta method using the secondorder inverse differentiation formulas with a variable step has been applied for solution of a mathematical model in the MatLab Simulink system. The equation of an electrical circuit for an inductor motor phase has been compiled according to the second law of Kirchhoff. The LEMET traction characteristics have been obtained by moving a locking and adjusting element (LCE) from 0 to 6 mm in steps of 1 mm while changing the MMF in the winding from 0 to 2 A in steps of 0.1 A. It has been established that in order to move the LCE by 6 mm with the speed of 40 mm/s with a resolution of 0.15 mm, the maximum value of the current in the LEMET winding is equal to 2.5 A. In this case the value of the electromagnetic force is 120 N. This makes it possible to improve an accuracy of the brake drive pressure regulation by 12.3 %. Solutions have been proposed to increase the LEMET speedwork. Characteristics of the engine have been described and numerical parameters of LEMET have been determined in the paper. The developed simulation model allows to investigate functional properties and dynamic characteristics of the proportional modulator with a relative error of 4.07 %.

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.

A meaningful characteristic of modern industrial production is given and prospects for the modernization of the Belarusian industry through new industrialization are identified in the paper. In this regard, the objectives of the study have been determined: to consider modern concepts of the transformation of economic systems under the influence of technological progress, to substantively characterize the new industrialization, including to describe the technological and organizational features of the new intentional production, to identify its distinctive features, to determine the prospects for using the concept of new industrialization for modernization of the Belarusian industry. The methodological basis was the general scientific methods and principles of сognition, namely: the method of deduction and induction, the method of comparative analysis, historical approach. The author considers the new industrialization as an economic structure that has developed as a result of the spread of digital technologies in a modern socially-oriented, predominantly market economy. The technological basis of the new industrial production is cyber-physical production systems that operate through the industrial Internet of things, the Internet of services and network mechanisms of interaction between all participants in the value added chain. The development of digital production and digital services entails the digitalization of business models. The result is flexible, adaptive, individualized industrial production through the triad of digital production, digital services and digital business models. When modernizing the Belarusian industrial complex, aimed at developing high-tech and knowledge-intensive industrial production and increasing the efficiency of traditional industries through the use of a wide variety of new technologies, the priority should be the comprehensive digitalization of production, services and business models.

During operation, concrete and reinforced concrete structures are exposed to the aggressive environment of carbon dioxide. During the reconstruction and overhaul of the berthing facilities in the coastal zone of the seas of the Far East, a weak bond strength of the “old” carbonated and “new” repair concrete has been established in the paper. The reason that prevents reliable adhesion of concrete is the formation of fragile corrosion products in the pores and on the surface of “old” concrete. Accelerated tests of concrete carbonization from exposure to carbon dioxide have been carried out in the course of the study. The structure of the carbonized cement stone has been examined using a scanning electron microscope. The research results have made it possible to assess the structure of a “healthy” cement stone and affected by carbonization. The performed analysis of concrete carbonization process, including micrographs of the samples, has shown that under the action of carbon dioxide, the surface layer with a thickness of 4 mm and more undergoes structural restructuring. Fibrous formations are destroyed, and the carbonized volume is a heap of loosely bound loose new formations and films blocking the entrances to the capillary system of concrete. They are not a reliable basis for adhesion of “new” and “old” concrete and prevent the penetration of liquid containing cement dissolution products from “new” concrete into the capillaries of the healthy structure of the “old” concrete for their reliable connection.

A large class of systems that have found application in various industries and households, electrified transportation facilities and energy sector has been classified as electrical engineering systems. Their characteristic feature is a combination of continuous and discontinuous modes of operation, which is reflected in the appearance of a relatively new term “hybrid systems”. A wide class of hybrid systems is pulsed DC converters operating in a pulse width modulation, which are non-linear systems with variable structure. Using various methods for linearization it is possible to obtain linear mathematical models that rather accurately simulate behavior of such systems. However, the presence in the mathematical models of exponential nonlinearities creates considerable difficulties in the implementation of digital hardware. The solution can be found while using an approximation of exponential functions by polynomials of the first order, that, however, violates the rigor accordance of the analytical model with characteristics of a real object. There are two practical approaches to synthesize algorithms for control of hybrid systems. The first approach is based on the representation of the whole system by a discrete model which is described by difference equations that makes it possible to synthesize discrete algorithms. The second approach is based on description of the system by differential equations. The equations describe synthesis of continuous algorithms and their further implementation in a digital computer included in the control loop system. The paper considers modeling of a hybrid electrical engineering system using differential equations. Neglecting the pulse duration, it has been proposed to describe behavior of vector components in phase coordinates of the hybrid system by stochastic differential equations containing generally non-linear differentiable random functions. A stochastic vector-matrix equation describing dynamics of the processes has been obtained in the paper. The equation contains both continuous and discrete components, which characterize an amplitude signal modulation. An equation for probability density of phase coordinate distribution in the system has been developed on the basis of a mathematical model for a hybrid system.

The paper presents the technology of obtaining flat-conical lenses (axicons) by the method of free grinding a work-piece to a flat tool through a layer of abrasive suspension. For this, theoretical and experimental studies of the regularities of stock removal from the base of the cone and its lateral surface have been carried out. The processing modes have been identified that ensure both uniform operation of the flat surface of the part and enhanced removal of the allowance in the edge or central zone of this surface. During the study of the processing of the conical surface, the set-up parameters of the technological equipment have been established, at which there is a minimum deviation of the generatrix of the cone from straightness and maximum productivity of the process. The stages of processing conical lenses are proposed, which allow to assign the optimal sequence of operations in the manufacture of this type of parts from blanks of a cylindrical shape in cases where the ratio of the height of the cone to the diameter of its base H/d £ 0.5. The main stages of processing include: grinding of the bases of cylindrical blanks with maintaining their mutual parallelism with a given accuracy; polishing one of the cylinder bases to achieve the required roughness and deviation from non-flatness; fastening a cylindrical blank to an auxiliary plane-parallel glass plate using molecular cohesion forces; mechanical fastening of a cylindrical work-piece with a collet adapter mandrel for a plane-parallel glass plate; applying the nearest sphere to the second base of the cylindrical blank; drawing a conical surface on the spherical part of a plano-convex lens; grinding and polishing the conical surface to achieve the required roughness and straightness of the cone generatrix. The degree of efficiency of the setup parameters of the machine has been revealed depending on the technological heredity of the work-piece from the point of view of the distribution of the allowance to be removed over the machined surface.

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.

The paper shows results of an experimental and theoretical study of dynamic processes in the vehicle transmission after kinematic alignment of elements during gearshifts. The purpose of the research is increasing the quality of transient processes in the vehicle transmission. Applying an analysis of experimental results obtained through looking into dynamics of a 3-ton vehicle transmission and studying literature sources it was established that dynamic loading of the transmission after the kinematic stage of shifting (i. e. synchronizing speeds of driving and driven elements in the gearbox) is influenced by oscillations which are in the single-node mode. Solving the task of increasing transient processes is achieved by applying a method of control power redistribution. By employing simulation models a number of methods were used to regulate power redistribution. Results of computations made it possible to determine that the efficiency of power redistribution are closely related to initial conditions of the process under the study. In the progress of the research a method for identifying the initial conditions was developed. This method is based determining signatures of the torque and its derivatives. In accordance with the research results it turned out that it is appropriate to apply the ZVD (zero vibration derivation) algorithm of power redistribution for low gears (below 4th) from point of view achieving better overshoot and robustness characteristics and a satisfactory response rate level. For higher gears it is recommended that the Ramp algorithm (linear increase in the control input) be used for the cases when the response rate is not longer than period of the single-node mode of oscillations occurring in the dynamic system during a gear shift. Application of the proposed algorithms allows to bring down dynamic loading of the transmission and also to improve the comfort in vehicles.

The paper shows that creation of materials with antibacterial and antifungal action presupposes an introduction of additives in them. One of the directions concerning fight against mold fungi is an inclusion of biocide additives having vegetable origin in structure of polymer materials used for manufacturing packing products. The main mission of anti-microbial additives is reduction of microbe amount in product mass and on its surface. Activity of anti-microbial compounds depends on the following parameters: concentration of active component, pH, temperature, polymer type, introduction method (with plasticizer or in melting state) and time period of their contact with polymer. In addition it is necessary to take into account such not unimportant factor as sensitivity of micro-organisms. Modern film polymer materials ensure only a certain level of product protection. They can not targetedly affect biochemical and microbiological changes in a packing product. It is necessary to develop new packing materials with selective permeability that create a barrier on the way of extremely intensive gas and moisture exchange, outside microflora flow, and prevent an evolution of undesired micro-organisms on packing products. Polymers have been selected as a basis for a bactericide packing material. Investigations have shown that composition including PEHP 98% (polyethylene of high pressure) + DGR (disproportionate gum rosin) + DETA (diethylenetriamine) has inhibited (hindered) sufficiently in a good way growth of mold fungi and PEHP composition with additives of tallow pitch and polyethylenepolyamine has demonstrated a rapid deterioration of strength characteristics and an increase in additive of the supposed mixture including pine oleoresin (POR) with DETA and DGR (with DETA more than 2%) hinders rapidly strength material characteristics.