Study of methods for estimating the viscosity coefficient of metals

Problem setting. The coefficient of dynamic viscosity of metals is used in many branches of human life, but its search, for a more accurate assessment and interpretation, is currently insufficiently studied due to the variety of its application [1-4], as well as due to the uncertainty of the constant parameters of the environment in which it is applied or investigated. Target. Consider a number of known methods for estimating the viscosity coefficients of metals at different ranges of strain patterns. Results. The methods considered for estimating the viscosity coefficient of metals, during their scientific and theoretical study, did not give an unambiguous answer for determining the viscosity of metals. Practical significance. Further study of the dynamic yield strength and the dynamic viscosity coefficient of metals is necessary to achieve more complete results of the method of evaluating the viscosity coefficient of metals.

Development of a method for assessing the quality of machine translation based on ensemble methods in machine learning

Automatically assessing the quality of machine translation is an important yet challenging task for machine translation research. Translation quality assessment is understood as predicting translation quality without reference to the source text. Translation quality depends on the specific machine translation system and often requires post-editing. Manual editing is a long and expensive process. Since the need to quickly determine the quality of translation increases, its automation is required. In this paper, we propose a quality assessment method based on ensemble supervised machine learning methods. The bilingual corpus WMT 2019 for the EnglishRussian language pair was used as data. The text data volume is 17089 sentences, 85% of the data was used for training, and 15% for testing the model. Linguistic functions extracted from the text in the source and target languages were used as features for training the system, since it is these characteristics that can most accurately characterize the translation in terms of quality. The following tools were used for feature extraction: a free language modeling tool based on SRILM and a Stanford POS Tagger parts of speech tagger. Before training the system, the text was preprocessed. The model was trained using three regression methods: Bagging, Extra Tree, and Random Forest. The algorithms were implemented in the Python programming language using the Scikit learn library. The parameters of the random forest method have been optimized using a grid search. The performance of the model was assessed by the mean absolute error MAE and the root mean square error RMSE, as well as by the Pearsоn coefficient, which determines the correlation with human judgment. Testing was carried out using three machine translation systems: Google and Bing neural systems, Mouses statistical machine translation systems based on phrases and based on syntax. Based on the results of the work, the method of additional trees showed itself best. In addition, for all categories of indicators under consideration, the best results are achieved using the Google machine translation system. The developed method showed good results close to human judgment. The system can be used for further research in the task of assessing the quality of translation.

Local territorial navigation system for regional airfields of the Arctic region RF

The specific conditions peculiar to the Northern regions create a number of difficulties in the functioning of the information airfield structure based on the traditional complex of navigation aids. These difficulties are caused by the unstable operation of satellite navigation systems in the Arctic region and territorial fragmentation. There is an urgent need to develop new approaches and technical means for the deployment of local navigation systems that ensure the operation of airfields with low traffic and difficult flight conditions. The aim of the study is to develop approaches to the creation of a new generation of multifunctional radar systems for the organization of a local navigation and information system at the airfields of the Arctic region, consisting of a ground-based multifunctional station, a portable small-sized terminal installed on board the aircraft and a board-to-ground communication line. This article proposes a promising navigation and territorial system for Arctic airfields, based on a new generation of information tools, including multifunctional radar stations. The proposed local territorial navigation and system is based on the information of the ground-based multifunctional airfield control radar. The information is transmitted to a portable small-sized terminal installed on board the aircraft. In this system, when transmitting the current situation to the on-board terminal from the multifunctional radar, which is linked to the airfield control center, it provides a safer implementation of the approach and landing modes at Arctic airfields, including in the complete absence of satellite navigation. The implementation of the proposed principles and technical solutions will enable the creation of a new generation of technical tools and the introduction of new organizational approaches to the creation of local navigation systems.

Prospects for the implementation of neural network technologies in radar information processing systems

Conducted studies of the phased implementation of neural network technologies in the practice of processing radar information, providing for a gradual increase in the level of neural network methods in processing systems, have shown that the use of neural network technologies can improve the quality of radar information processing in the most difficult conditions that require high computing power, when the dynamics of changes in external conditions is very is high and traditional approaches to the creation of processing systems are not able to provide the required level of efficiency. The need to develop theoretical provisions for neural network processing of radar information was revealed, while the main features of information processing in radars determine the relevance of research devoted to preventing the reduction in the quality of radar images in conditions of a large number of targets and a complex «jamming» environment based on the rational use of neural network technology. Analysis of the phased implementation of neural network technologies in radar information processing systems, as well as the use of neural network technology for processing radar information in terms of search and research, makes it possible to increase the efficiency of neural network methods for all processing tasks. Assessment of the required performance of computational tools allows us to single out the main neural network paradigms, the use of which gives a tangible increase in the efficiency of radar information processing, such as multilayer perceptron, Hopfield associative memory and self-organizing Kohonen network, while it is possible to rank the proposed methods in accordance with the required performance, undemanding to computing power and implemented on existing or promising computing facilities with software implementation of neural network paradigms. The analysis of possible directions for improving the quality of radar information processing does not claim to fully cover the entire multifaceted area of such studies. In this paper, only the most universal and widespread neural network paradigms are considered and the main part of possible areas of their application is analyzed. However, the proposed options show that the use of neural network technologies in critical tasks will improve the efficiency of radar information processing for complex, rapidly changing external conditions. The use of the principles of self-learning and the developed apparatus for the synthesis of neural network methods will reduce the duration and complexity of theoretical research, the conduct of which is a necessary and mandatory part of the traditional approach. In the course of further research, some of the proposed methods can be refined, as well as the emergence of new methods that make it possible to more fully use the advantages of neural network technology. Carrying out further research work in these areas will give a powerful stimulating impetus for the creation in the future of highly efficient methods for processing radar information, which can be implemented on the available element base.

Investigation of the effect of doping the GaN buffer layer with carbon on the avalanche breakdown effect of normally open HEMT AlGaN/AlN/GaN transistors

The influence of the GaN buffer layer doped with carbon on the avalanche breakdown effect of normally open HEMT AlGaN / AlN / GaN transistors was studied. The avalanche breakdown was simulated in a structure where the gate length is LG = 0.3 mkm, the distance between the source and gate is LSG = 1.5 mkm, and the distance between the gate and drain is LGD = 2.2 mkm. For modeling, consider a layer doped with carbon, the thickness of which is 0.3 mkm, and the layer is located at a distance of 20 nm from the channel. The Simulation showed that with an increase in the concentration of carbon doping of the buffer, the breakdown voltage increases in the range UB = 225 – 360 (V). When the layer thickness changes to 0.4 mkm, the breakdown voltage increases in the range UB = 230 – 446 (V). For a structure where the gate length is LG = 0.8 mkm, the distance between the source and the gate is LSG = 1.0 mkm, the distance between the gate and drain is LGD = 3.0 mkm, the breakdown voltage increases in the range UB = 300 – 622 (V).

Low-frequency ultrasound bactericidal capacity study in intermittent ultrasonication process

The low-frequency ultrasound (f = 26.5 kHz) was found to have a bactericidal effect upon the main representatives of bacterial flora: Staphylococcus, Proteus, E-coli and Pseudomanas aeruginosa. However, ultrasound suppresses bacterial flora during a comparatively long ultrasonication time ranging from 18 to 27 min. It was found that the determinant factor ensuring the bactericidal effect of low-frequency ultrasound is cavitation. To reduce the required ultrasonication time, while maintaining the high bactericidal effect, Bauman Moscow State Technical University (BMSTU) has developed a new ultrasonic treatment method designed for infected wounds and patented in the RF [8]. When implementing this method, it is proposed to intensify the cavitational effect of ultrasound through complementary physical and chemical factors: low-concentration antiseptic agents, excessive external static pressure, and optimum temperature of ultrasonicated solution. The proposed intensification of ultrasonic effect was found to reduce the sterilization time of bacterial suspensions from 5 to 7.2 times, while keeping the maximum required ultrasonication time within 5 min. The article considers further potential reduction of cavitational exposure time for tissues on the basis of earlier found aftereffect of ultrasound. This aftereffect means that a pre-sonicated solution has higher bactericidal properties than non-sonicated solutions and preserves its bactericidal capacity for specific time [11]. The article demonstrates the efficacy of the continuous ultrasonication process replacement by the intermittent process, which follows the cycle: ultrasonication – pause – ultrasonication. Experiments proved that, with optimum temporal relationship between the periods of ultrasonic exposure and rest, the complete sterilization end-time of bacterial suspensions can be reduced still more by 20…30%. Thus, the proposed intermittent ultrasonication process is an effective instrument of reducing the cavitational exposure of an organism, while maintaining its high bactericidal effect no worse than that of the continuous ultrasonication process. The research findings were successfully tested in the Traumatology department of N.N. Burdenko Main Military Clinical Hospital during the trial of the proposed method for ultrasonic treatment of infected wounds.

Development of differential correction of coordinate-time and consumer navigation support based on trajectory data comparisons

The article deals with the use of the results of measuring the catalogued space objects coordinates by a radar station for long-range detection in the interests of differential correction of coordinate-time and navigation support for consumers. We describe the idea of comparing trajectory data that allows us to calculate the total electronic content in the direction of a catalyzed space object under the assumption of a thin layer at the height of the ionosphere maximum. The main stages of the method of differential correction of coordinates-but-time and navigation support for consumers based on the results of comparing trajectory data are described. The results of modeling are presented, which allow us to evaluate the possible positive effect when using the proposed approach.

“Regulatory Guillotine” – dangers and prospects for industrial enterprises

The article analyzes the problems associated with the reform of control and supervisory activities to reduce the administrative burden on business entities. Special attention is paid to the mechanism of the "regulatory guillotine" in the Russian Federation, as a comprehensive update of mandatory requirements. This reform is especially relevant for organizations that produce high-tech products, since it is at these enterprises that the requirements corresponding to the current level of scientific and technological progress should be applied. As a research goal of the article, the authors analyzed the features of the introduction of the "regulatory guillotine" mechanism for industrial enterprises. As a result of the analysis, it is established that it is necessary to apply a process-oriented approach in the implementation of control and supervisory activities. It is determined that on the one hand, the mechanism of the "regulatory guillotine" for enterprises will reduce unnecessarily unjustified control and supervisory checks, form a system of regulation of control and supervisory activities, and minimize administrative pressure. The new regulatory and legislative framework (mandatory requirements) should be consistent and unambiguous, meeting the requirements of the time and technological development of enterprises, based on the most significant public risks. This will allow businesses to reduce costs and remove barriers to development. On the other hand, it is established that the implementation of the "regulatory guillotine" mechanism strongly depends on organizational and managerial aspects: the definition, justification and development of mandatory requirements that ensure a risk-based approach to control and supervisory activities is a difficult task for all participants of the reform, requiring them to be prompt and consistent. The implementation of the "regulatory guillotine" may take years and enterprises will have to work in the mode of uncertainty of the regulatory framework for several more years, and the establishment of a large number of uncontrolled exceptions contributes to the ambiguity of control and supervisory procedures. The article defines the difficulties of implementing the mechanism of the "regulatory guillotine" in industrial enterprises.

Investigation of the attenuation of the fluxes of the low-energy plasma component of electric rocket engines by the ventilation holes of the unpressurized instrument compartment of the spacecraft

The results of an experimental study of the attenuation of the fluxes of the low-energy component of the plasma formed during the operation of electric propulsion engines (ERE), ventilation holes (VH) of the non-sealed equipment compartment (NSEC) of the spacecraft (SC) are presented. Authors studied the attenuation of plasma fluxes by standard VHs made in honeycomb panels that form the NSEC. A Hall-effect engine of the SPT-70 type was used as a plasma source. The experiment consisted of measuring the plasma concentration at the inlet and outlet of the VH. The concentration at the inlet was measured with a flat Langmuir probe, and at the outlet with a Faraday probe, which allows collecting all ions passing through the VH. The aim of the work was to study the weakening of the fluxes of the lowenergy component of the EJE plasma when passing through the VH in the honeycomb-nels that form the NSEC. Based on the experimental data, a semi-empirical model was constructed that describes the dependence of the attenuation coefficient of plasma flows on the geometric parameters of the vent-holes. It has been established that a vent-holes of this design attenuates the plasma flows by 102 ... 104 times. The largest contribution to the weakening of plasma fluxes is made by the honeycomb filler, which is due to the recombination of ions during their collision with the channel walls. Taking into account the attenuation of the fluxes of the low-energy component of the plasma of electric rocket engines by ventilation holes is a key stage in assessing the effect of plasma on the power on-board equipment of spacecraft and should be used by spacecraft developers when analyzing the resistance to this factor.

Analysis of the prospects for the introduction of a closed-loop economy in the Russian Federation using the example of the Kaluga region

In a number of industrialized regions of the Russian Federation, even when using efficient high technologies in the manufacturing industry under the current linear economic model, especially in the context of pandemic (COVID-19) fails to implement the sustainable development goals in all of its ecological and economic requirements. This paper analyzes models and approaches to the implementation of the concept of renewable production and consumption in conditions of maximum use of resources, including those obtained by processing various types of waste. According to the analyzed one of the models, namely the circulation economic model, resources after consumption in the form of manufactured products and the resulting waste, suitable for processing into production resources, in the form of secondary. Within the framework of rational interaction of the industrially developed regions (Moscow and Kaluga), an experimental confirmation of the efficiency of waste processing of various types is given, by building an Ecotechnopark, implemented within the framework of public-private partnership, and obtaining secondary products. In the proposed circular economic model, resources after consumption in the form of production products are returned to production after processing. In addition, a possible indicator was identified and implemented that allows integrating traditional economic indicators into the "Green" gross national product (GNP), which is the sum of the natural capital of the region and its nominal GNP and is linked to the state of the ecosystem. Recommendations and conclusions on the performed studies are made.