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Molecular genetic studies of 221 strains of enteroviruses isolated from patients with HFMD and neuroinfections from different provinces of Vietnam in 2018-2021 were carried out. 20 types of enteroviruses have been identified: CVA2, CVA4, CVA5, CVA6, CVA8, CVA10, CVA16, EV-A71, CVA9, CVB1, CVB2, CVB4, ECHO4, ECHO6, ECHO9, ECHO11, ECHO16, ECHO29, ECHO25, ECHO30. Genetic heterogeneity of Vietnamese enterovirus strains has been established.

With a view of implantation of space technology in activities of Ministry of Internal Affairs (MIA) and commercial organizations it is necessary to work through technology of robototechnical complex control in real application conditions. Aim. Investigation of reachable accuracy of coordinate definition of moving objects using global space navigation technology for the benefit of MIA. There are examined problems of coordinate definition accuracy increasing using global space navigation technology that were investigated in pilot project «MIA-Roscosmos». There are given results of onboard equipment tests that were worked in the regime of differential correction data using. There were used navigation apparatus of a geodesic class and the mobile measuring-diagnostic laboratory. There are defined possible field of application of navigation apparatus in an activities of MIA. There are formulated recommendations to using of global space navigation apparatus for the benefit of MIA.

An overview of heat and corrosion-resistant steels of domestic and foreign production, used for the manufacture of aircraft rolling bearings, is presented. The requirements for bearing steels, the classification of steels depending on the operating conditions, and the method of production are described. The chemical compositions of the steels and the principles of alloying are shown, and the analysis of the properties is carried out. The properties of ceramic materials and the possibility of their application for bearings used in the aerospace industry are considered.

Subject. The article addresses the issue of adequate representation of economic dynamics. It considers the need to take into account internal nonlinear processes being an important factor and additional mechanism for managing the economic dynamics. Objectives. The purpose is to rationalize a transition to a new probabilistic mapping of economic dynamics based on modern methods of nonlinear dynamics, which enables to establish the relationship between internal nonlinear processes and macroeconomic indicators of the economic system. Methods. We employ a systems analysis of stages of State-run programs formation, a probabilistic approach to representing the economic dynamics on the basis of fundamental concepts and methods of nonlinear dynamics. Results. We analyzed the cycles of government program formation for developing the high-tech products, established the identity of the main stages of economic and nonlinear dynamics. We also designed a methodology for studying the economic dynamics, which rests on the use of nonlinear dynamics methods. Modeling the processes of economic dynamics made it possible to determine the causes of its sensitivity to initial conditions and exponential divergence of its trajectory at initial stages of government programs formation. The paper presents methods to choose the optimal model of economic dynamics when substantiating and drafting the said programs. Conclusions. The findings can be used to improve methodological tools for managing the creation of high-tech products when elaborating long-term technological programs, to reduce risk inherent in their implementation, to determine methods and ways for sustainable innovative and technological development of the country.

Subject. The most important and responsible stage of justifying State programs for high-tech product creation is the balancing of program activities. This task becomes especially urgent when fulfilling the customer requirements for efficiency and quality of high-tech products under tight constraints on fund allocation. Objectives. The study aims to create a general balancing model based on a comprehensive analysis of the conceptual and methodological framework of balancing in various fields of activity. Methods. As a starting methodological premise – a scientific hypothesis, we substantiate the use of the principle of scientific syllogism, which includes general and special premises and a conclusion containing new scientific knowledge, and the principle of self-organization to take into account internal processes of balancing. Results. We formulated a conceptual framework for balancing to support the creation of high-tech products. On its basis we developed a general model and described its main parts, including the goal of balancing, conditions, criteria and parameters, and the result of balancing. We also formulated the general problem of balancing and methods to solve it. The paper shows that the problems of balancing and optimization on the one hand and the task of self-organization on the other hand are identical. Conclusions. The obtained results can be used to improve methodological tools to manage the creation of high-tech products while developing long-term technological programs, mitigate the risk of their implementation, define of sustainable innovative and technological development of the country.

Subject. The article discusses the methodological apparatus for assessing how many financial resources are needed, and optimize their gradual consumption in high-tech production projects. Results of the projects can be forecasted only as a probable estimate, since there is great uncertainty due to a multitude of random factors. Objectives. The study aims to form the methodological apparatus to assess the amount of financial resources needed under risk and substantiate the reasonable strategy for consuming them in high-tech production projects within a given period of time. The apparatus is to allow for quick adjustments of the financing plan and estimation of project expenditures. Methods. We applied the comprehensive approach to planning and regulating trends in high-tech production costs, methods of economic and mathematical modeling and the probability theory. Results. We reviewed methods used to assess how many financial resources are needed through demand probability distribution laws. Based on them, we devised the interval technique for regulating cost trends so as to substantiate the reasonable strategy for the performance of projects with the desired probability within the given period of time. What distinguishes the interval technique is that it provides the overall vision of the period, during which the project will be performed, and the probability of the advanced prediction of a shortage or excess of financial resources. Conclusions and Relevance. The methodological apparatus proposed herein will facilitate the technological and economic evaluation of various options of high-tech production and choose those ones which ensure the best use of financial resources, quickly regulate the economic dynamism throughout the high-tech production phases in line with a variety of factors, which randomly emerge at certain phases.

On the basis of the methodology of mathematical modeling, the development of the transformation of oil hydrocarbons in the waters of the eastern shelf of Sakhalin Island is considered. Three electronic instruments for the analysis of oceanographic information were used: 1. GIS “Sakhalin shelf” (for processing and systematization of thermohaline observed parameters); 2. The oceanic model of the Bergen University (for calculating the velocities and directions of currents, and also flow rates of water exchange between the individual regions on the Sakhalin Shelf); and 3. CNPSi-model (for calculating the biotransformation of oil hydrocarbons taking into account the intra-annual changes of the long-term marine environment parameters and features of the substance transfer at the water exchange). The entire eastern shelf of the Sakhalin Island was subdivided on two Water Areas (1. southeastern and 2. northeastern ones), where Regions 1–3 and 1–4 were respectively allocated. Using the methodology of mathematical modeling, the CNPSi-model reproduces the interactions of the changing environmental factors during a year (temperature, light intensity, water transparency, oil hydrocarbon inputs from external sources, conditions of the water regime) and their influence on the biotransformation of oil hydrocarbons in two-layer marine environment. The model calculates the changes during a year of the oil hydrocarbon concentrations, the biomass of B2 bacteria (they oxidize of the oil hydrocarbons) and their activity indexes (the specific growth rate, the total biomass turnover time and the biomass production). An analysis is made of the changes in these parameters depending on environmental factors and conditions of substance transport during water exchange across the boundaries of regions and with open water areas of the Sea of Okhotsk. For each region studied, the characteristic values of these parameters were revealed for specific periods of a year. Calculations show that there are different conditions for the formation of B2 bacteria biomass and their production on the south and north regions of the eastern shelf of the Sakhalin Island. In Regions 1–3 of the southeastern part of the shelf (Area 1), a significant effect of water dynamics was found on the development of the biomasses of organisms and, in particular, on the B2 biomass.

The hyperboloid radio tower on Shabolovka Street built by V.G. Shukhov is one of the world known symbols of Moscow and of the USSR television broadcasting. The tower was laser scanned and 3D modeled in detail in 2011–2013 years. Virtual 3D modeling involved a thorough analysis of the existing historical documentation. This analysis revealed many discrepancies between the actual structure of the tower and existing historical documentation (including the design, working and survey documentation). In this paper we describe differences regarding the outline of the tower, structure of legs and connection joints, the height of the tower, and also discuss some assumptions on the change of mounting method during the building of the first two sections.

The article describes the evolution of the cartography and toponymy of the second largest geyser field in the world – the Valley of Geysers in the Kronotsky Reserve (Kamchatka Peninsula, Ru...

Crosstalk effects are studied experimentally in a DWDM line with 100G DP-QPSK channels at a frequency convergence of the channels (three channels with a frequency separation of 50, 37.5 and 33 GHz) in the C-band. Spans of 100 km in length are used, with the number of spans varying from one to six. The required optical signal-to-noise ratio (OSNRR) is determined experimentally for a different number of spans, interchannel intervals and input power. We propose a theoretical model based on the numerical modelling that describes the influence of adjacent channels at a strong convergence. The model is calibrated using the obtained experimental data. Based on the proposed model, we calculate the maximal value of the spectral efficiency in systems with a dense arrangement of 100G DP-QPSK channels (~3.2 bit s−1 Hz−1).

We report an analysis of the problems encountered in the design of modern high-bit-rate coherent communication links. A phenomenological communication link model is described, which is suitable for solving applied tasks of the network design with nonlinear effects taken into account. We propose an engineering approach to the design that is based on the use of fundamental nonlinearity coefficients calculated in advance for the experimental configurations of communication links. An experimental method is presented for calculating the nonlinearity coefficient of communication links. It is shown that the proposed approach allows one to successfully meet the challenges in designing communication networks.

The accumulation of nonlinear noise in multi-span communication lines was investigated by numerical modeling and experimentally for different values of accumulated dispersion at input of each span. One coherent 100G channel was investigated (wavelength 1549.32 nm, DWDM channel C35). It has been established that interaction of nonlinear noises from two different spans can be described by a correlation function that depends only on values of input dispersion for these spans. It confirms the idea that the nonlinear noise in a fiber optic line is formed mainly due to signal to signal interaction, and the influence of the signal to noise interaction can be neglected. The shape of correlation function was investigated by numerical modeling and experimentally, and its simple approximation was offered. The nonlinear noise in any multi-span line with arbitrary dispersion plan can be calculated based on the investigated correlation function for two spans. It was shown that in a compensated line the offered theoretical model based on correlation function corresponds well to simpler theoretical model based on superlinear dependence of total noise on number of spans.

The article is devoted to the analysis of non-technical factors affecting the development of fiber-optic communication systems. It discusses the role of socio-economic factors in stimulating a new round of technical development of communication systems in the late 2000s and the emergence of coherent systems. Author analyses the stages of development of coherent systems in the second decade of the XXI century and reveals the influence of psychological factors on the emergence of a new class of coherent systems using two optical carriers. It is shown that the choice of a technical solution using two carriers was caused, first of all, not by the internal logic of technology development, but by the marketing need to accelerate the achievement of a psychologically significant transmission speed of 400 Gbps.

This paper examines stimulated Brillouin scattering (SBS) suppression in multichannel DWDM systems owing to nonlinear cross interaction between the channels and its effect on optical signal quality in a communication link. We present an experimental study of single-, three- and five-channel systems with NRZ channels. The optical signal quality in the three- and five-channel systems is shown to be better than that in the single-channel system. The reason for this is that cross-phase modulation broadens the spectrum of the signal and raises the SBS threshold. This in turn ensures a more pronounced optical signal quality improvement due to self-phase modulation.

Design of DWDM lines requires calculation of optimal input powers for each span. It is called “optimization of DWDM network”. Different approaches are currently used to solve this task including maximization of optical signal-to-noise ratio (OSNR) margin and minimization of bit error rate (BER). Within last years there is a particular interest to DWDM lines based on uncompensated links with coherent transmission. We analyze benefits and drawbacks of existing approaches and offer a new method of optimization that guarantees sufficient OSNR margin for bringing into service such DWDM lines. The proposed method combines the advantages of two previously known methods. For short lines, it works like BER criterion. It does not overestimate values of power, and does not require the recalculation after each stage of expansion of the line. For long lines, it works like OSNR margin criterion. It guarantees that calculated values of powers will enable bringing the line into service; and if the optimization is failed it means that it is impossible to commission the line by any other method. Discussion and comparison of different methods are based on a general phenomenological model for multi-span fiber optic line that takes into account both linear and nonlinear noises. The proposed phenomenological model is a consequence of the GN model where a number of parameters characterizing nonlinear interaction of DWDM channels are determined experimentally.

On the example of the magnetic field sensor shown that the developed sensing element type thin-film SOI MISIM transistor with built-in channel provides the creation of sensors with substantially improved electrical characteristics (magnetic sensitivity, temperature range). The physical model of a sensor is considered and justified the choice of the optimal electrical regimes. It is shown that the operation temperature range of the magnetic sensing element is from LHT up to at least 330 °C. Theoretically predicted the possibility of increasing the temperature limit by 200–300 °C depending on the functional purpose of the sensor. Developed and implemented microelectronic operating voltage stabilizers of sensors and electronic keys operating at temperatures of 230 °C and not less than 300 °C, respectively. It is shown that the developed sensor and functional elements provide to create multifunctional multi-channel high-temperature sensor of magnetic field and temperature.

The nature of accumulation of nonlinear noise in multi-span communication lines with optical amplifiers without dispersion compensation was investigated experimentally and theoretically. It has been established that the dependence of nonlinear noise power on the number of spans is described by a power function with an exponent greater than 1. It has also been established that the nonlinear noise power generated in one span is practically independent on the amount of dispersion accumulated before this span for the values of accumulated dispersion more than 2 ns/nm. Since the noise power generated in one span does not depend on number of this span, in order to describe the superlinear dependence of total noise on number of spans we can assume that noises generated in different spans are correlated.

The Shabolovka radio tower in Moscow, also known as the Shukhov tower, is a famous example of the Russian avant-garde style of the early 20th century. With a height of approximately 160 m, it is the highest hyperboloid lattice steel tower ever built by Shukhov and is one of the symbols of Moscow. It is widely recognized as an artifact of modern cultural heritage. Despite being an iconic object of engineering and architectural heritage, it was deprived of technical maintenance for many years. Its technical condition has degraded since the early 1990s and has now reached an alarming level. Several restoration projects are still being discussed by the Russian government, including the full rebuilding of the tower in another place. Therefore, digital preservation of the tower's original geometry and design has become a crucial task. Its under-documentation is also a concern: the initial project and engineering documentation is almost completely lost. To preserve information about the tower, we performed laser scanning and created a precise polygonal 3D model using both the results of the scanning and the existing drawings. The transition from an unstructured point cloud to a highly structured representation included the development of a special methodology to model deformed steel elements of hyperboloid sections. The tower was scanned from seven viewpoints, resulting in a 65 M point cloud. To reproduce the individual shapes of twisted rods and rings, we used > 4 K pre-defined cross-sections. These were precisely positioned in a point cloud. The connection joints of steel elements were modeled using drawings based on measurements that were made in 1947. Non-original design elements such as service platforms and an elevator were also modeled using the point cloud. We also made use of historical drawings and photographs to represent the internal structure of the concrete basement and the non-extant original superstructure. The combination of various methods of 3D modeling for different parts of the tower allowed us to visualize the geometry of the huge steel construction with high accuracy (1 cm or so) and with high level of detail in a reasonable timeframe (300 man-days). Public access to large 3D models and to vast amounts of raw data is a sensitive issue for virtual heritage applications. To provide free access to our results, we created an open-source software application based on Open Scene Graph. It supports stereo visualization of the point cloud and the 3D model, as well as management of the visibility of different layers of the model in accordance with its lifecycle period. A light web-version based on Unity 3D is also being developed to provide Internet access to the model. The software is freely available at our website ( http://virtual.ihst.ru/shukhov-tower.html ). Thus, we created a comprehensive visual representation of a steel lattice radio tower of the early 20th century and shared precise technical documentation with researchers worldwide. The experience that we have gained can be useful for other similar projects that involve precise polygonal modeling of large-scale objects of modern cultural heritage.

The construction of Si Hall element formed in thin Si layer of SOI structure is considered. Hall element is a part of SOI FET accumulation mode transistor with built-in channel and MISIM field control systems. Such Hall element characterized by wide range of operation temperature from liquid Helium temperature up to 650K.

The performance of fiber optic communication systems reached its maximum several years ago with the introduction of 100 Gbit/s systems (100G). The further development of communication systems is going in such directions as complicating the formats of modulation, increasing the flexibility of tuning the occupied spectrum and increasing the speed of transmission over the carrier. This is advantageous for short lines, but leads to a significant reduction in transmission range and performance. Thus, the record performance of the 100G systems can be considered a marker for the transition from the revolutionary stage of the development of fiber-optic communication technologies to the evolutionary stage of their development.

The study addresses the implementation of the project “A Virtual Model of Denisova Cave in the Altai Mountains” generating a 3D model of the cave and pinpointing certain key finds. The project includes the elaboration of software for interactive visualization in the virtual space of the cave. Apart from information about this unique site, the model is aimed at solving certain research problems. This is the first Russian attempt to create a virtual 3D model of a cave site.

The transformation of nutrients in marine environments of the northeastern part of the Sakhalin shelf was studied. Based on the data on the status of the thermohaline parameters of sea water, the dynamic ocean model and the hydroecological model, the seasonal dynamics of concentrations of organic and mineral substances for growth biomass aquatic organisms are presented.

Objectives: The article considers various methodological approaches to estimate the costs for creating high-tech products used in the leading countries. Methods: HTP economic evaluation model proposed by the authors is based on modern methods of assessing the costs for the HTP creation. In its economic essence, they are all based on a common methodology for assessing the results and costs in their various combinations and modifications. However, the current assessment techniques do not allow carrying out a comprehensive feasibility study of HTP. Findings: It has been specified that the existing methodologies for estimating the costs do not allow making a comprehensive feasibility estimate of options for sharing of new and traditional technologies when creating high-tech products. Specific peculiarities that are necessary to be considered in economic evaluation of high-tech products have been found. A number of models for economic evaluation of high-tech products have been suggested. These models are based on modern methods of estimating costs to create high-tech products used in leading countries. According to their economic essence, they are all based on a common methodology for estimating the results and costs in their various combinations and modifications that provides a comprehensive feasibility estimate of high-tech products. The practical implementation of the proposed models allows conducting a feasibility assessment of the sharing options for new and traditional technologies when creating high-tech products and choosing the options that ensure rational use of budgetary funds allocated for these purposes. Applications/Improvements: These models are universal and can be used in all sectors of the economy of the technologically developed country.

Evolution of a two-level system (TLS) in a strong resonant quantum field is considered beyond the rotating wave approximation (RWA). An analytical expression for the atomic population inversion that approximates numerical results with high accuracy is deduced. It allows us to describe new qualitative peculiarities of the TLS evolution in the strong field: i) suppression of the ‘collapse–revival’ effect, and ii) change of the spectrum and form of the population oscillations.

The existing models for regulating the dynamics of the creation of science-intensive products are very fragmented; they are based on various initial data and do not allow giving a comprehensive assessment of the feasibility of RandD for the creation of science-intensive products within a given time, especially in risk.Financial and economic risk; scientific, industrial and technological risk. Taking into account these types of risk, we introduce a methodical tool. This is a complex model for regulating economic dynamics designed for a probabilistic and cost description of the dynamics and results of the creation of science-intensive products.The model provides a complex tech-economic evaluation of projects to develop high-tech products in risk. This model has a universal character and can be used in all branches of economics of a technologically developed country. In practice, this complex model can be useful at the stage of selection of competing organizations designs with the purpose of evaluating their capacity to implement projects, as well as at the stage of adjusting the funding plan and cost estimates for the creation of science-intensive products.This model may be used in planning bodies to assess the capabilities of design organizations in the implementation of orders for the creation of science-intensive products.

The evolution of a two-level system in a single-mode quantum field is considered beyond the rotating wave approximation. It is shown for the first time that the Rabi oscillations of the system are modified in the resonant way at some values of the field amplitude.

Principles of constructing systems for generating DTDs for a collection of XML documents are discussed. Methods and algorithms for creating DTDs are developed. A DTD generation system for a collection of XML documents is developed. This system can efficiently be used both for solving applied problems and for theoretical studies.

Self-sustained oscillations of the current with a frequency ranging from 0.7 to 3.6 MHz have been detected in weakly coupled GaAs/AlGaAs superlattice at 4.2 K. A study of the static and dynamic characteristics of the structure showed that the spontaneous oscillations arise in the local region of the superlattice, restricted by a size of the domain boundary expansion. The oscillations arise in the negative differential conductivity regions due to the periodic coupling and decoupling of subbands in adjacent quantum wells, forming the expanded domain boundary. We suggest that the spatio-temporal oscillations of the domain boundary should be considered as oscillations of an ensemble of several strongly phase-coupled oscillators. Each oscillator is a couple of two adjacent quantum wells, which operates as a single resonant tunneling diode.

Virtual 3D model of the Valley of Geysers, Kamchatka provides virtual travelling and interactive storytelling in the cyberspace and serves for scientific visualization, geodynamical processes modeling, disaster preparedness and response, environmental studies, ecological education, and virtual ecotourism.