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Renewable energy sources are gradually becoming useful in mining industry. They are actively used in remote, sparsely populated areas to power shift settlements, geological and meteorological stations, pipeline equipment, mobile cell towers, helicopter pads lighting, etc. In comparison with diesel generators, systems with renewable sources do not require fuel transportation, have short payback periods and flexible configuration for different categories of electrical loads. The main obstacles to their spread are instability of generation and high cost of produced electricity. One of the possible ways to solve these problems is to develop new technologies, increase power density of generators and energy storage systems. The other way represents energy saving and rational use of affordable resources. The new solutions for implementation of the second method are proposed in this work. The object of the study is autonomous DC electrical complex with photovoltaic and wind power sources. In such systems the generated power from renewable sources is transferred to consumers via intermediate DC bus, the voltage level of which affects the power losses in the process of power transmission. The vast majority of complexes have a problem that their DC bus voltage is constant, while the optimum voltage level with lowest losses varies depending on the generated and consumed power. Therefore, electrical complexes potentially lose a part of the transmitted energy. To avoid this, a special algorithm was added to automatically adjust DC bus voltage to optimum level according to changes in working conditions. An additional contribution to efficiency improvement can be made by dynamic change of operating frequency in power converters depending on their load. The evaluation based on results of computer simulation showed that in a complex with rated power 10 kW active power losses during its lifetime can be reduced by 2-5 %.

The use of wind power plants is growing rapidly, despite the continued growth in the extraction of traditional fossil resources. In this paper, the analysis of the power curves of real wind turbine models and the polynomials common among the scientific community describing the dependence of the wind turbine output power on wind is carried out. The article discusses 82 models of wind power plants with a horizontal axis of rotation, rated power up to 100 kW and with a method of limiting the speed of rotation in the operating mode pitch control. The calculation of the potential generation of each wind turbine at an oil and gas field for a period of twenty years with an interval of one hour is carried out, the Installed Capacity Utilization Factor is calculated, after which the values are compared with the results of calculations based on polynomials of other authors. The results obtained can be widely applied in modeling the operating modes of wind power plants and will improve the accuracy of feasibility studies for the implementation of autonomous power supply systems.

Objective. To review a literature published over the past 5 years and our own data on the etiology of lower respiratory tract infections (LRTI), antimicrobial resistance and its relationships between sepsis and choice of appropriate antibiotic therapy. Materials and Methods. National Nosocomial Infections Surveillance (NNIS) criteria were used to diagnose LRTI. A review of the articles regarding LRTI from the Russian and international English language journals published over 6 years was performed. Identification of microorganisms was performed by culture over the period of 2003–2013; since 2014, MALDI-TOF MS method was used for this purpose. Results. Despite the ongoing policy to limit the use of antimicrobial therapy in the ICUs, there is an increase in carbapenemase-producing isolates in the ICUs from 2.2% (2018) to 11.7% (2020, 9 months). Along with the trend to increase in carbapenemase-producing pathogens causing LRTI, their variability is also increasing. In particular, it applies to strains producing carbapenemases OXA-48 or combination of OXA-48 with KPC; with the trend to combined production of carbapenemase beginning at 2019. Conclusions. Carbapenemase producers are becoming more widespread in the ICU settings, including the lower respiratory tract in mechanically ventilated patients. Practitioners didn’t get used to associate VAP with the Sepsis-3 criteria. The changes in etiology include the increased rate of carbapenem-resistant Enterobacterales and non-fermenting Gram-negative bacteria, primarily Acinetobacter spp., in Russia. It’s due to improved quality of respiratory support and increased consumption of carbapenems, tigecycline and polymyxins. Significant increase of OXA-48-producing pathogens is likely to be associated with a poor compliance with temporary guidelines on COVID-19 with regard to antibiotic therapy.

In this article, the authors consider the possibility of using a hybrid energy storage system to even out the load profile of the enterprise. Solving the problem of rational use of energy storage taking into account the initial variable load schedule will significantly reduce not only the cost of electricity consumption by the enterprise, but also the costs of its production. Detailed characteristics of batteries with various types of electrolytes and supercapacitors are given. A model of the active scheme of a hybrid electric energy storage system consisting of a lithium-ion battery and a supercapacitor unit with the corresponding characteristics is presented. The model was carried out by using the SimPowerSystems software in MatLab. During the simulation, the temperature and the aging effects and of the batteries were not taken into account. The selfdischarge parameter of the battery was also not presented. As a result of the simulation, discharge characteristics of supercapacitors and batteries were obtained based upon which the expediency of their combined use for leveling load profiles of various types was substantiated. The paper presents the results of the simulation of operating modes of a hybrid energy storage device, combining the advantages of two types of energy storage devices, as well as a diagram of delivered power to the network, corresponding to the specified parameters. The paper provides a mathematical description of the increasing power by hybrid storage system resulting from the combined use of supercapacitors and batteries. The paper presents the dependence of the power increase ratio on the frequency and the pulse current duty ratio, which proves that the maximum possible output power of the hybrid storage system can be several times greater than the power of a single battery having the same parameters.

The synchronization coefficients values are calculated for a given synchronization bands with non-linear properties of the synchronized generator. The experimental results show the effect of an external signal not only on phase noise, but also the amplitude fluctuations.

The estimation of influence of the microwave sensor frequency short-term instability on the information processing device operation accuracy in a security alarm system is presented. Results of theoretical calculation of microwave sensor noise characteristics and experimental data are given. Calculation of a sharply directed conic antenna with a dielectric lens is executed and results of experimental researches of its directional diagram in E - and H -planes are resulted.

The principles of constructing of phase shifters with variousphase measurement methods are considered. The schemes realizing the given phase shift on the basis of strip, coaxial or waveguide lines, as well as the expressions for calculation of the given phase shift, parameters, characteristics and design features of switching diodes of the microwave range are given.

The article considers the issues of monitoring of the educational institutions official websites in the Republic of Belarus, beginning with the 2018 interms of its influence on the potential of services export in education. Special attention is paid to a state and development of information resources of higher education institutions. Regulatory legal acts and other documents forming a normative basis of monitoring are analyzed. The organization of monitoring processes of the education institutions websites is considered in the manual regime as well as using the utomated information system for auditing education institutions information resources in the Republic of Belarus, assessment of their state and relevance is also considered (AIS Monitoring). The criteria for evaluation of the websites included in monitoring are presented and their comparison at the manual and automated way of realization is carried out. The analysis of monitoring results of the education institutions official websites in 2018 including that realized within trial operation of AIS Monitoring is produced. The correlation between the growth in the number of foreign students in higher education institutions and indicators for monitoring of information resources is assessed. The results of a quantitative assessment of the dependence of the growth rate of the number of foreign students at Belarusian universities on the level of compliance with the requirements for the informational content of official sites in terms of the list and cost of services provided in the form of a regression model are presented. Recommendations for further development and improvement of monitoring processes of information resources are formed.

In this article, the authors reviewed a new technology to prevent the formation of asphalt-resin-paraffin deposits by the thermal method of electrothermal impact on the oil wellbore shaft using a wind-electric installation as an autonomous power source. The advantage of this thermal stimulation technique lies in its continuous nature, which will allow keeping the clear opening of the tubing constant. The scheme of the autonomous system for down-hole electric heating of oil is presented. A tubular or induction heater can serve as an electric heating element placed in the well. The heating element of the system can be used in the wells exploited by freeflow, gas lift and mechanized methods, while its installation does not require an overhaul. The paraffin oil saturation temperature and temperature distribution over the depth of the well were defined. The amount of heat, which must be transferred to the oil mixture in the tubing in order to ensure effective operation of the well, taking into account the dynamic state of the system, is calculated. The optimal depth of the heating element's location in the well and its power was determined. The calculation of the required power for wind-electric installation to maintain the set temperature in the wellbore was performed. Having conducted the studies, it was revealed that in order to prevent the asphalt-resin-paraffin deposits formation on the tubing walls of oil wells, it is expedient to use the in-line heater, which maintains the average steady-state temperature along the wellbore and at the wellhead above the initial crystallization point of the asphaltresin-paraffin deposits. The application of the developed electrothermal system is relevant in the conditions of formation of asphalt-resin-paraffin deposits in the wellbore shaft at the fields, which do not have a connection to the centralized power grid.

In the article we examine relevant problems regarding human rights on roads with arising digitalized processes. The problems cover three aspects. First, are the rights of drivers, passengers, and impaired individuals who use digitalized management systems while on the roads. Second, is the protection of the rights of those who are dismissed from driving the public transport with digitalized management systems. Third, is the potential danger to the society from economic outcomes of further digitalization. In the end, the article gives a comprehensive argument about the importance of securing human rights on the roads as it was brought up to our attention by the United Nations.Following the afore mentioned aspects of the problem, the article derives hypothetical solutions regarding human rights of road users with arising digitalized process. First of all, it remains essential to reinforce drivers’ rules on the roads. Next, safety of pedestrians, people who are travelling on foot, needs to be ensured since they are worse off in case of an emergency on the roads. Finally, it is a special focus on ensuring the rights of persons with disabilities. The latter applies not only to the drivers and pedestrians, but also to passengers with disabilities who use the means of urban ground transportation.

The article considers the issues of formation and maintenance of an integrated information management system in the education sector, as well as the development of e-education on the example of the Republic of Estonia — a regional and one of the world leaders in the field of digital transformation of education. The history and specificity of the information system in the Estonian education sector (EHIS) is analyzed in the context of the development of e-government technologies. The principles for the processes of collecting, processing and analyzing information in the education sector in Estoniaare presented, the expanded analytical capabilities of the information system containing personal data of various categories of participants in the educational process are described. The issues of ensuring confidentiality and integrity of information based on digital signature and blockchain technology are considered. The economic and social effect of the implementation of an integrated information system in the education sector has been revealed. The structure of e-learning services in Estoniaand their role in providing digital transformation of the education system are considered. As a result of the analysis of the Estonian experience in the formation of an integrated information system in the education sector, as well as the development of e-education services, scientifically based recommendations for the modernization of the education system of the Republicof Belarushave been developed.

The article analyzes the condition and prospects for the development of passenger route transport in the Russian Federation, provides the rationale for the need to improve the efficiency of public transport, which will contribute to the economic and social development of the city, region and the country as a whole. The existing problems were identified and a set of measures aimed at improving the efficiency of urban passenger transport was defined.

The article considers the essence of the economic risks of transport companies, features of risk management in the transport sector. Selected problems of managerial decision-making under uncertainty. Deals with the analysis and risk assessment. The necessity of a systematic approach to risk management in transport.

Objective. To evaluate the results of accelerated identification of microorganisms isolated from positive hemocultures obtained from patients of various departments of a large multi-profile hospital by MALDI-TOF MS and to compare them with classical cultural methods. Materials and Methods. In the period from 2017 to 2018, the study included 109 positive blood cultures from 73 patients from UIA GKB number 40 at the age of 1 to 83 years. Blood samples were taken in aseptic conditions from 2 peripheral veins according to the standard protocol in 12 departments of the health facility. Identification of the grown up colonies was carried out by 2 methods: phenotypic (using the automatic bacteriological analyzer Vitek 2 (BioMerieux, France), biochemical tests, Gram stain, catalase test, oxidase, latex agglutination) in the laboratory of microbiology and MALDI-TOF MS on the Vitek MS analyzer (BioMerieux, France) in the QualityMed laboratory. The transportation of blood from the health facility to the laboratory was carried out with the help of a courier, the delivery time varied from 7 hours to 2 days. Polymicrobial hemocultures (4 vials), cases of fungemia (4 vials), and also 1 vial because of late delivery times are excluded from the study. Results. In total, out of 100 vials included in the study, 70 strains of Gram-positive bacteria and 29 strains of Gram-negative bacteria were isolated. Another 1 strain of Streptococcus pneumoniae was not obtained in culture due to the phenomenon of autolysis. In general, the percentage of successful accelerated identification for all groups of bacteria was 86.0%, and for gram-negative rods it reached 100%, for gram-positive cocci – 83.5%. Conclusions. The use of methods for accelerated identification of positive blood cultures with MALDI-TOF MS allows faster and reliable detection of pathogens of gram-negative bacteremia. The effectiveness of detection of gram-positive cocci is reduced to 83.5%.

The article touches upon the topic of using 3D-printing technologies in education. 3D-printing technologies can be used to teach technological skills in engineering and design as the main tool. They also help to reorient attention from the digital or virtual environment to the real world, because as a result of learning activity, not sketches and layouts, but real objects with specified characteristics act. 3D-printing technologies are fast-developing and promising technologies that can find their application in various fields, including in the field of education. These technologies due to the appearance of personal printing devices can facilitate the introduction of new forms of organization of the educational process, increase the motivation and formation of the necessary competencies of graduates and teachers.

The concept of digital transformation and its difference from informatization processes are considered in the article. The dynamics of the share of the gross added value of the ICT sector in theRepublicofBelarusis analyzed, and this indicator is compared with the OECD countries. A multiplicative index model that allows assessing the influence of the main factors on the dynamics of the share of the ICT sector in the GVA has been developed. A cluster analysis of the types of economic activity on the indicators of the use of ICT was carried out (e-mail, Internet, local area networks), as well as the availability of its own website, as a result of which groups of "digital leaders" and "digital outsiders" were singled out. The estimation of readiness of the economy of theRepublicofBelarusfor digital transformation in 2016 is presented on the basis of the share of economic activities that are "digital leaders" in the total value of GVA.

An analysis of current trends in the prevalence of nosocomial infections, their etiology and antibiotic resistance in pathogens was performed. Social and economic consequences of antimicrobial resistance as well as a medical community’s response were shown. A role of the AMRmap Internet resource in monitoring antibiotic resistance in Russia was demonstrated. The results of our own approaches to the antimicrobial therapy stewardship in the intensive care service of a large hospital were evaluated.

The article analyzes the condition and prospects for the development of passenger route transport in the Russian Federation, provides the rationale for the need to improve the efficiency of public transport, which will contribute to the economic and social development of the city, region and the country as a whole. The existing problems were identified and a set of measures aimed at improving the efficiency of urban passenger transport was defined.

In article it was resumed modern concepts of interventional chronic total occlusion retrograde recanalization. It was introduced advantages and disadvantages of particular approaches. It was described created by authors new way of retrograde CTO recanalization (CART-M method) and clinical presentation of this method was shown. It was announced potential advantages of CART-M method comparing with other methods of CTO recanalization.

The article considers the essence of the economic risks of transport companies, features of risk management in the transport sector. Selected problems of managerial decision-making under uncertainty. Deals with the analysis and risk assessment. The necessity of a systematic approach to risk management in transport.

У цій статті проводиться дослідження філософських поглядів К. Д. Ушинского в період навчання в Московському університеті. Становлення поглядів Ушинского багато в чому визначалося соціально-політичною атмосферою, що оточувала його. Відзначається, що роки, проведені в стінах університету, наділили його соціально-філософським багажем, що став основою, наріжним каменем його теорії морального виховання. Закінчивши навчання в Московському університеті К. Д. Ушинский почав самостійну науково-педагогічну кар'єру. Критично відносячись до дійсності, що оточує його, К. Д. Ушинский не бачив, та і не міг ще бачити реальних сил, здатних перебудувати суспільство на принципах свободи і соціальної справедливості. В той же час він вірив, що громадський розвиток в майбутньому неминуче приведе до урочистості гуманістичних ідеалів. І борг кожної чесної людини наближати світле майбутнє усіма доступними для нього засобами

The article discusses the experience of operating a wind power complex with a low-power wind power installa- tion (5 kW), the use of which is promising for powering remote oil production facilities, exploration and other types of mining operations. The structure of the studied complex and its characteristics, technical problems that have arisen during operation for 6 years are given. The elements of the wind energy complex – the battery charge regulator and the inverter-converter are considered. The consequences of the mechanical regulator failure of battery charge are con- sidered and recommendations for its replacement are presented. The issues of diagnostics and repair of one of the main elements of the complex – the inverter-converter, its component – DC link are highlighted in detail. Oscil- lograms of the output voltage of the inverter-converter are presented for different capacities of the DC link and the images of the repaired inverter-converter are given. Recommendations are given on choosing an inverter-converter and setting up the operating modes of the wind energycomplex.

Splenic artery steal syndrome is one of possible arterial complications after orthotopic liver transplantation. Material includes personal experience in diagnostics and treatment of this syndrome. In each case complication was opportunely suspected basing on laboratory and ultrasound data and proved by angiography. Successful treatment was performed using different variants of splenic artery embolization.

In practice it’s often observed the discrepancy between clinical presentation of cerebral lesions in neonates and results of instrumental studies (neurosonography and computer tomography). The aim of the research was to explore the possibilities of the method of EEG for diagnosis and prognosis of cerebral lesions in neonates. The study was carried out in the design of Longitudinal prospective cohort controlled comparative non-randomized study with a simple glare. The study results demonstrate a great diagnostic and prognostic value of the method of EEG in detecting cerebral ischemia in neonates.