Aim. This article is devoted to the conversion of solar radiation into electricity using the joint effect of several methods, which complement each other by transforming the disadvantages of one method into the advantages of another method. Methods. Heat exchange processes occurring under multiple re-reflection of the light flux on a cylindrical solar concentrator were simulated. Results. It is proposed to form an integrated set of semiconductor photon conyerters together with a photoelectric effect on metal electrodes, thus producing a low electron output and a thermoelectric effect. This approach increases the energy efficiency of the entire structure with an additional multiple rereflection of photons on the solar flux concentrator in the form of a cylindrical surface with radially arranged mirror metal electrodes. When reaching a power-effectiye integrated thermoelectric con-yerter of solar radiation to electricity, photons will either be conyerted at the p-n junction of a solar cell, or participate in the photoelectric effect at the electrodes, or be absorbed by the construction material to produce thermoelectric power. This approach allows the efficiency of the entire system to be maximized. Conclusion. All the photons that hit the proposed power-effectiye integrated thermoelectric solar radiation conyerter will be conyerted to electricity to a certain extent, with only their small part being scattered outside in the form of heat losses or re-reflections.

Aim. To analyse the prospects of developing and applying thermoelectric semiconductor energy converters in medicine. Methods. The research was based on theoretical and experimental achievements in the field of creating devices producing thermal effects on individual areas of the human body. Results. Fundamentally new devices with different thermal schemes based on thermoelectric semiconductor converters were created for diverse medical applications. A number of theoretical and experimental works were conducted to create a theoretical basis for the proposed devices. The prospects of developing and applying thermoelectric semiconductor heat devices in medicine were considered. The design of devices for providing thermal influence on individual areas of the human body was described. Conclusion. The developed thermoelectric semiconductor devices and devices for producing local thermal effects on individual organs of the human body ensure their use in medical practice due to simplicity and reliability.

Aim. The study describes a prototype of an intelligent system for modelling climate variability based on a database of multi-year series and historical evidence. The presented intelligent system allows climate events to be simulated as follows: one phenomenon at one point; one phenomenon in space; many phenomena at one point and many phenomena in space. Methods. The choice of research methods was determined by the properties of source information and its volume: a series of observations over a long period, sampling over a short period, historical and archival materials, etc. Results. The article describes the main functions of the presented intelligent system, which expand the possibility of assessing the variability of climate characteristics by combining quantitative and qualitative information in the form of historical and archival evidence. The main functions of the system include the generation of event flows; estimation of the event probability; physical reconstruction of data using geoinformation systems; determination of the period between two rare events; and management of agricultural production under risk conditions. Conclusion. The advantage of the proposed system consists in increasing information about extreme events and improving the management efficiency by means of reducing risks.

Aim. One of the key objectives of the theory and practice of information security is to analyse the functioning of protected automated systems, particularly those operated at computerized facilities of internal affairs bodies. In order to identify potential threats to resources of confidential information, to assess the risk of threat implementation, as well as to form a list of potential threats to automated systems installed at computerized facilities of internal affairs bodies, it is necessary to analyse the composition and architecture of automated systems, identify the features of their protected functioning and determine the vulnerability of software and hardware systems. Methods. A comprehensive analysis of the functioning of protected automated systems during their operation at computerized facilities of internal affairs bodies was conducted. Results. Following an analysis of normative documentation and research publications in the field of protecting information in automated systems, departmental records of the Ministry of Internal Affairs of the Russian Federation, regulations for the protection of information at computerized facilities of internal affairs bodies, the structure and architecture of a protected automated system were defined. Potential threats to the functioning of such a system, including cyber attacks, were identified. On the basis of a survey among experts in the field of information security, the vulnerability (in term of cyber attacks) of the software components of an automated system installed at computerized facilities of internal affairs bodies was analysed. Conclusion. The results can be used in the process of designing and operating information security tools and systems installed at computerized facilities of internal affairs bodies for the purpose of improving their security.

Aim. To compare the effectiveness of evaluating the publication activity of organizations and authors by such indexing systems as Google Scholar, Scopus and RINTS, as well as to assess the reliability and credibility of these indexing systems in terms of measuring research performance. On the basis of this information, the reliability of the systems currently used to rank Belarusian universities, in particular the University of Grodno, was estimated. Methods. This article analyses and compares the effectiveness of various indexing systems, which is extremely relevant due to the widespread use of the Google Scholar, Scopus, and RINTS indexing systems in Belarus. Results. The general characteristics of the above-mentioned indexing systems and their significance in assessing the research performance of university staff are given. A comparative assessment of the indexing systems was carried out, including their specific features, advantages and disadvantages. The conducted analysis of the ideology and mechanism of indexing research data using Google Scholar proved the unreliability and inconsistency of this approach for evaluating research performance, as well as the fallacy of adopting this system for evaluating the publication activity of university staff. Conclusion. The analysis of the Russian Science Citation Index (RINTS) also revealed significant imperfections. However, the use of RINTS does provide a fairly objective comprehensive assessment of the publication activity of authors and organizations. In addition, RINTS enables an analysis of the structure of indicators, which is completely impossible using Google Scholar and Scopus.

Aim. The article considers the physical basis for the formation of a technical channel of information leakage due to low-frequency acoustoelectric transformations. Methods. The research was based on simulation modelling methods. The method of instrumental and computational control of the security of speech information in the considered channel of information leakage was applied. Results. Based on the developed simulation model, using the Model-View-Presenter design pattern, a software tool was developed. The main software classes implementing this model are presented. The functionality of the developed software tool is demonstrated and recommendations are given on the possible application of the developed simulation model for identifying threats to information security due to low-frequency acoustoelectric transformations. Conclusion. The developed simulation model can be used by security specialists at both large and small enterprises, which implement measures for ensuring information protection. The model creates conditions for its active implementation in the educational process of training specialists in the field of information security, using both traditional (contact work) and distance learning formats.

Aim. Modern industrial production requires an improved level of information management. This problem can be approached by creating an information space based on a virtual enterprise model. Methods. The article presents the structure of a virtual enterprise for industrial enterprises based on the integration method chosen as a result of comparative analysis of the Lotsman product life cycle assurance system using the solution of the Askon Corporation. A virtual enterprise is considered as a multi-agent system; the description of its levels, organizational units, their relations, actions, inputs and outputs, performed tasks, environment and states is given. Each set is presented as a formula with useful explanations and comments. Results. As an example, an algorithm for producing an engineering product is presented, which demonstrates the simplicity and convenience of designing products within the developed model of production organization. Conclusion. The article proposes the developed model of a virtual enterprise based on the Lotsman PLM system in the form of a multi-agent system. The key elements and interactions of this model are described, and the convenience of the model is demonstrated on an example.

Aim. At present, the construction of data transmission networks is undergoing rapid development, which actualized the problem of the timely maintenance, repair, and modernization of network equipment. This article provides a step-by-step description of the decision support system for evaluating the elements of data transmission systems used to improve the efficiency of telecommunication network maintenance. Method. The research methodology involved the methods of system analysis, fuzzy set theory, neural networks, graph theory, and mathematical modelling. Results. A decision support system was developed for evaluating the operational state of the elements of data transmission system during operating the network infrastructure of a communications service provider. Conclusion. The developed decision support system reduces the workload of highly qualified personnel and improves the quality of decisions made during the development of data transmission networks.

Aim. This work conducts a comprehensive analysis of system relationships between the main technical and technological indicators of technological blocks functioning at underground uranium leaching mines. Methods. An information model describing the operation of technological wells was created. This model was used to determine the relationship between the main volume and quality indicators of reserves development, such as the volume of mining mass, the volume of discovered reserves, metal recovery, the average concentration of uranium, and the value of the ore interval. Results. For an adequate assessment of the reserve of technological blocks, the initial set of factors determining the volume of discovered reserves and production volumes at the field was formed: the interval of the effective capacity of the acidified productive horizon; the grouping of technological wells in the block; the area of the technological block. The analysis of geological and technological information carried out using the developed information model, along with an assessment of the resources during field mining, showed that 76% of operating technological blocks demonstrated overrecovery according to the actual results or the results predicted by forecasts. Conclusion. The results of reserve recalculation showed that the real reserves of uranium in the subsurface did not correspond to the actual development. In addition, it was found that systematic underestimation of discovered reserves was also associated with the calculation of uranium content in ore intervals, i.e., taking into account the value of the radioactive equilibrium coefficient.

Aim. Web resources are an integral part of modern human life. Today, these resources are increasingly exposed to hacker attacks, such as the introduction of SQL operators, crosssite scripting, etc. DDoS attacks continue to be included in the top 10 network attacks that lead to serious failures of web resources. The most common type of DDoS attack is UDP-flood attacks based on the endless sending of UDP packets to the ports of various UDP services. Our empirical study was based on the following factors: the lack of effective means of protection against DDoS attacks, the specificity of UDP-flood attacks, and the lack of prediction models that adequately describe the process under study. The aim of this study was to increase the level of security of web resources by means of timely detection of anomalies in their work, detection of information security threats based on analysis and forecasting methods. The research object was UDP-flood attacks. Methods. Correlation analysis and modelling methods were used to calculate the seasonal index of UDP-flood attacks and the autocorrelation of the time series of this type of attack. The forecast of UDP-flood attacks was built based on simple exponential smoothing and neural network forecasting models. Results. A classification of DDoS attacks was proposed, along with possible protection approaches. Using a correlation analysis, the forecast values of the impact of UDP-flood attacks against web resources were calculated, and the seasonal factor was identified. The analysis of the forecast results showed that the spread of forecast values was not significant; the largest number of attacks is expected in the fourth quarter of 2020. For DDoS attacks lasting up to 20 minutes, seasonality was also detected in the first quarter of the calendar year, which means that the largest number of attacks of this duration should be expected in the first quarter of 2020. Conclusion. In order to improve the level of protection against DDoS attacks, further research should be aimed at developing methods for combating UDP-flood attacks and algorithms increasing the information security of web resources, as well as implementing measures to improve the security of web-based resources.

Aim. The research aims to develop mathematical models for evaluating the reliability of two-story frame systems under the seismic impact, covering all possible ways of transition to the mechanism state due to the formation of plastic hinges in the frame nodes. Methods. The study is based on the application of the theory of Markov random processes in continuous time and their discrete states to describe the transition of a system into a different state. Such states include faults resulting from the formation of plastic hinges in the frame nodes. Results. Possible schemes of forming plastic hinges in two types of statically indeterminate frames under horizontal seismic impact are described: in the frame of a 2-story industrial building with a large-span upper floor and with the support of the roof truss on the heads of columns and a two-story two-span frame of a simple regular structure with rigid nodes. Possible states are noted and transition graphs are compiled, which are typical for the frames under consideration in the case of rigid disks of floor slabs during seismic impact, represented as a stationary random process. By representing the transition of systems to the states under consideration caused by the formation of plastic hinges in one or another sequence under seismic action in the form of a Markov random process in continuous time and discrete states, systems of first-order differential equations describing these transitions are obtained. Having solved them by applying the Laplace transform, analytical expressions for estimating the probabilities of finding frame systems in the states under consideration and expressions for estimating the probabilities of failure-free operation of these systems are obtained. Conclusion. By constructing transition graphs covering all possible states of frame systems during the formation of plastic hinges in nodes under seismic action and describing the process of frame transitions from one state to another by a Markov random process in continuous time and discrete states, analytical expressions for evaluating the probabilities of these system states, as well as their reliability and survivability under seismic action, can be obtained.

Aim. This study was aimed at developing methods for improving the quality of bituminous binders by means of their modification. Methods. A method for regulating the process of destructing rubber granulate on an industrial scale, under which rubber granulate undergoes physical and chemical interactions with plasticized bitumen at a temperature of 230°C, was applied. Results. The article reviews existing publications devoted to the modification of petroleum road viscous bitumen with various polymers, in particular with rubber granulate obtained by processing waste of the rubber industry. The process of obtaining bitumen modified with rubber granulate through a two-stage technological process is described. The dependence of the physical and chemical parameters of the binder on the technological modes is estimated. The results of evaluating the structure of a modified binder, as well as the rubber granulate before and after thermomechanical processing, are presented. A comparison of the physical and chemical properties of bitumen modified with various rubber-granulate forms in a two-stage technological process with analogue products is presented. Conclusion. The proposed two-stage technological process of modifying bitumen with rubber granulate increases the homogeneity of the system and facilitates the formation of a dispersed framework reinforcing the binder, which leads to the production of a binder with improved physical and chemical characteristics. Rubber granulates impart an increased temperature stability and elasticity to the modified bitumen by means of forming tiny bumps on the surface of the particles.

Aim. The article aims to present a solution to a resolving equation for determining the stress-strain state of a rod of non-circular cross-section under torsion, taking into account the material creep. Methods. The solution is based on the hypotheses introduced by Saint-Venant when considering an elastic rod. Finally, the problem is reduced to a second-order differential equation in terms of the stress function. The solution of this equation is performed using the finite element method in combination with the Euler method. Results. The work presents resolving equations for a triangular finite element. The solution of a test problem for a polymer rod of rectangular cross-section is given, the material of which adheres to the nonlinear Maxwell-Gurevich equation. Graphs of changes in time of the relative twisting angle, as well as the maximum values of tangent stresses, are presented. Conclusion. It is established that the stresses in the rod are not constant over time. The tangent stresses in the rod during creep initially decrease followed by a return to the elastic solution.

Aim. To analyse the possibilities of various computational methods (primarily numerical) in terms of investigating the stress-strain state of complex multi-dimensional vertical loadbearing systems. Methods. The fundamental essence of the finite-difference method (grids) and the finite element method is revealed, their advantages and disadvantages are described in terms of solving the plane problem of elasticity theory, in particular, in calculating the stress-strain state of panelframe structures united in a single vertical multi-connected system. Results. The obtained results can be used to optimize the methodology of theoretical stress-strain state analysis of complex multiconnected systems, taking into account available computer equipment and licensed software packages for automated calculation of building structures. Conclusion. The conducted analysis shows that, provided there is a sufficiently powerful computer, the finite element method is the most versatile and effective method. This method was the basis of a large number of software packages permitting analysis of the stress-strain state of any designs characterized by the complexity of form, topology, load, etc.