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In this paper, effects of low and high ambient temperatures on the operation of a photoelectric unit are investigated. The research methodology consisted in determination of the energy efficiency of a photoelectric unit across a wide range of ambient temperatures, providing graphical interpretations and describing the procedure of field observations. Regularities in determining the average statistical indicators of energy efficiency rise and drop in a photoelectric unit were applied for a particular range of ambient temperatures. These studies were undertaken during the winter of 2021 in the Materials Science Laboratory of V.P. Larionov Institute of Physical-Technical Problems of the North, Siberian Branch of the Russian Academy of Sciences, using a fixed climate chamber. Reference parameters were obtained for changes in the photoelectric unit generating capacity (within -60ºC to +60ºC), which can be applied in modeling operational processes and engineering calculations of operating conditions of solar power plants. It was found that, at the same illumination and ambient temperature values, a photoelectric panel generates the maximum energy at -60ºC and minimal energy at +60 ºC, with the specific power drop for this temperature range being 19%. A significant drop in the specific power of the photoelectric unit was achieved at +30 ºC and higher due to the increased internal resistance of the unit. For temperatures below -40ºC, the specific power of the analyzed unit increased insignificantly due to the decreased internal resistance of the unit. The obtained values of the generating capacity of a photoelectric unit within a wide range of ambient temperatures can be used in developing a procedure for evaluating the effects of ambient temperature and its various ranges on the operation of photoelectric units, as well as for a more accurate determination of the solar generation energy potential under certain climate conditions. In future studies, field observations are planned to identify the nature of the effect of two and more climatic factors on the operation of a photoelectric unit.

This study investigates the effect produced by various types of cloudiness on the functioning of a photovoltaic system in the central part of the Republic of Sakha (Yakutia). The electric power efficiency of the photovoltaic system under various cloudiness conditions was assessed using graphical interpretations, measuring and recording devices, as well as a description of the procedure for conducting experimental work. The average indicators of a decrease in the electric power efficiency of the photovoltaic system were determined using patterns for a certain type of cloudiness. A specific cloudiness type was identified by performing measurements and calculating illumination ranges, taking boundary conditions into account. These studies were carried out during the summer period of 2021 using the facilities of the mobile test site of the V.P. Larionov Institute of the Physical-Technical Problems of the North of Siberian Branch of the Russian Academy of Sciences located in the central part of the Republic of Sakha (Yakutia). Control parameters of alterations in the generating capacity of the photovoltaic system were obtained for 10 types of cloudiness. The obtained parameters can be used when modeling operational processes and performing engineering calculations of the operating modes for solar power plants. According to the results, during the operation of photovoltaic systems under various types of cloudiness, the decrease in the generating capacity of the installation can vary within 8–95% relative to the generating capacity indicator under clear weather. The obtained indicators of alterations in the generating capacity of a photovoltaic system under various cloudiness conditions can be applied for developing a methodology for assessing the effect of cloudiness and its types on the carrying capacity of solar beams falling on the photovoltaic panel surface, as well as to more accurately determine the energy potential of solar generation in a certain area.

The article offers a comparative analysis of the modern political realities in the United Kingdom and the Russian Federation. In that regard, there is a given account of the principal political problems which are springing from migration. The article offers an estimate of modern migration laws of the United Kingdom. The possibility of appliance of the British governmental initiatives up on the post-Soviet states by the Russian government is examined.

The aim of this study was to determine the dynamics of the residual infectious activity of the SARSCoV-2 virus on various types of surfaces, including banknotes and coins, in samples of drinking dechlorinated water and samples imitating seawater, with a concentration of sodium chloride salts of 0.9 and 3.5 % at a temperature of 24–28 ºC.Materials and methods. The studies were carried out using the SARS-CoV-2 coronavirus strain nCoV/Victoria/1/2020, from the collection of the SSC VB “Vector”, the initial titer being (6.0±0.2) lg TCD50/ml. We used a Vero E6 cell culture from the collection of the SSC VB “Vector” in the form of a 2-day monolayer with a confluence of 95–100 %, grown in 96-well culture plates.Results and conclusions. The SARS-CoV-2 coronavirus is viable in both fresh and sea water, regardless of its salinity, for at least 48 hours, and the degree of preservation of the residual infectious activity of the virus depends on the water temperature: the lower it is, the better the virus is preserved. It was found that at a temperature of 24–28 C, the SARS-CoV-2 coronavirus is able to maintain infectious activity on all types of test surfaces studied for at least 48 hours, while the degree of the residual infectious activity of the virus depends on the type of surface. The virus is best preserved on stainless steel, plastic and glass. It is demonstrated that SARS-CoV-2 virus activity is retained on the surface of paper money and coins for longer than 24 hours. The conducted studies have confirmed the ability of the SARS-CoV-2 coronavirus to maintain its infectious activity in the environment under favorable conditions and, accordingly, to pose an epidemiological threat to the population.

An agreement between the content of amorphous (oxalate-extractable) iron and morphochromatic features of gley attests to the modern activity of gleyzation processes in tundra soils of the Kolyma Lowland, especially within lower parts of gentle and steep slopes. A suprapermafrost reduced gley horizon thawing out in the warmest years is considered a relic of the warmer and wetter stage of soil formation. An integrated analysis of data on the contents of mobile iron and annotated metagenomes indicates that microorganisms affiliated with the Proteobacteria phylum capable of iron reduction predominate in sediments formed under hydromorphic conditions and in modern mineral soil. In laboratory experiments, the process of microbial iron reduction was more active at 5°C than at 20°C. Therefore, it can be assumed that the majority of cultivated communities of iron-reducing bacteria have been adapted to low Arctic temperatures. Under conditions of climate warming and an increase in precipitation, permafrost temperature, and thickness of the seasonally thawed layer, iron reduction processes in the soils rich in the total iron will play an even greater role and create favorable redox conditions for the formation of methane, one of the most important greenhouse gases.

Objective. Applying microbiological method to determine the effectiveness of disinfection treatments with formaldehyde fumigation of the hidden cavities and the reverse side of the microbiological safety cabinet filters (MSC) located in the “infectious” areas of an isolated to maximum extent laboratory. Evaluation of the effectiveness of experimental unit for automation of the formaldehyde treatment of laboratory premises. Materials and methods. Assessment of effectiveness of disinfection treatments of MSCs and the premises of virological laboratory was carried out using cambric test objects contaminated with the spore-forming test culture of B. thuringiensis. Results and discussion. The disinfection time sufficient for the complete inactivation of particularly dangerous pathogenic microorganisms potentially located in hidden cavities and on the back side of microbiological safety cabinet filters, placed in the “infectious” zone of the most isolated laboratory has been determined experimentally. As a result of the studies, it was possible to achieve complete inactivation of the spore-forming test microorganism located on test objects situated in hidden cavities and hardly accessible places of MSC at concentration of 1·106 cells/cm3 only with disinfection time equal to 24 hours. Effective disinfection of test objects contaminated with B. thuringiensis spore-forming test culture, placed in hard-toreach places and on the back of the equipment in a boxed virological room, using an experimental plant producing gaseous formaldehyde, was possible only when formalin was used in a concentration of 40 ml/m3 of the room. It was established that the amount of formalin required to achieve 100% efficiency of the disinfection treatment of the virological boxed room using an experimental unit producing gaseous formaldehyde depends on the operating mode of the general supply and exhaust ventilation, the configuration of the laboratory room, and the furnishing with laboratory and engineering equipment.

An advanced thermoelectric system has been developed to set a low temperature to the heat-generating power semiconductor devices. The system provides the setting the temperature down to -60°C in a volume of 80x40x12 mm3 at the heat-release up to 13 W. Accuracy of setting the temperature is in the range of ± 3°C. The design of developed system is adopted for long-term tests, including tests in harsh environment. The cooling chamber in may be placed up to 6 m away from the heat exchanger and control unit. One of the main features of new development is its mobility and easy installation when carrying out various types of tests.

We provide a brief evolution trends overview of the modern microelectronic devices and its radiation behaviour, focusing on new structures and materials effects due to Total Ionizing Dose (TID) and Single Event effects (SEE) in CMOS elements. Evolution of test facilities driven by these changes in radiation behaviour of modern devices is also considered.

A description of the system for setting a lowered environment temperature based on Peltier modules is presented. The development was carried out taking into account the peculiarities of the radiation test: minimum distance from exposure source to DUT; stand-alone use during long-term radiation test; minimum overall dimensions, transportability and flexibility when conducting tests on various exposure sources. Cooling box consists of 3-level stacked assembly of the Peltier modules, which is cooled by liquid refrigerant. Control of the assembly of Peltier modules was performed according to proportional integral and differential algorithm, provided by microcontroller with feedbacks on Pt thermoresistors. The system provides temperature stabilization of the DUT up to 23х17х12 mm in size and with released heat power up to 0.4 W at minus (60 ± 3) oС. Temperature establishing time is less than 10 minutes. Typical power consumption of developed system is about 500W.

A methodical approach for the identification of a plant and characterization of integrated circuit technology based on an analysis of the features of a radiation response is proposed.

Heavy-ion-induced single event burnout (SEB) is studied experimentally for several types of 4H-SiC Schottky power diodes with various bias voltages applied. Safe operating voltage area for each type was defined and analyzed. The comparison with Si power devices was carried out.

This work presents a solution for radiation hardness assessment using compact and productive X-ray facilities, as well as the automated measurement system. The radiation test procedure can be integrated in commercial IC's process as a mandatory option for providing high reliability and radiation hardened IC projects. Using the radiation test procedure as a one of technology stage, the assessment of total ionizing dose (TID) hardness was done for test structures, which were fabricated in conventional 65 nm CMOS technology.

A control and indication unit for current operating parameters has been developed for the Spellman XRF-160 high-voltage generator with an output voltage of up to 160 kV, used as part of a high-voltage X-ray microtomograph installation. Thanks to the use of isolating amplifiers in the unit, galvanic separation of the circuits for the formation of control and indication signals with executive circuits of the high-voltage generator is implemented. This makes it possible to virtually eliminate the possibility of the formation of stray ground loops and the flow of dangerous pulsed currents from electrostatic and corona discharges of a high-voltage source in the sensitive circuits of the tomography recording camera and Ethernet communication with the control computer and, as a result, radically increase the reliability of the device. The unit supports the operation of the XRF-160 generator in the modes of stabilization of the output voltage or stabilization of the emission current of the X-ray tube and provides adjustment and indication of the main parameters of the high-voltage installation - the maximum permissible and operating filament current of the cathode, high voltage and emission current of the tube. The unit is assembled in a typical 19-inch case.

The article deals with a half-wave transmission lines, which are the most prospective for transmit an electric energy over long distances. At the present time, their technical feasibility and economic efficiency are substantiated and it is proved that the half-wave transmissions can work as a transit ones. At the same time, the issue of a power take-off is unresolved yet. The main feature of a half-wave transmission line is the voltage changes in the middle part of the line from the maximum, in the load mode, to zero, in the idle. This prevents the traditional parallel power take-off in this part of the line. The studies of the operation regimes of a half-wave transmission lines with the power take-off were conducted using the model of a half-wave transmission line. As a result, it have been developed the methods and ways for power take-off from the line. It is shown that the usage of the thyristor parameter stabilizer makes possible the power take-off at any intermediate point of a half-wave transmission line.

The SEB test results of 3 kinds and 17 types of power MOSFET were systemized in this work. Several common features of radiation behavior were found for tested devices. The approach to increase SEB sustainability area of MOSFET-based electronic devices was discussed.

Numerical and experimental evaluation of the influence of laser radiation polarization orientation on ionization response of 180-nm and 90-nm CMOS ICs is performed. Comparative research is carried out to determine how the polarization of various sized laser beams affects the parameters of IC ionization response. The necessity of considering the orientation of laser radiation polarization for laser local radiation effect simulation is shown.

The effect of the direction of laser polarization on the transient radiation response of an IC memory device implemented using CMOS technology 0.18 μm is estimated. The effect of laser polarization is investigated both for local exposure and exposure on the entire crystal. It is shown that the direction of laser polarization should be taken into account when simulating local dose rate effects.

Several approaches to nondestructive procedure of total ionizing dose hardness prediction and grading of each sample within a wafer or a packaged lot of SOI (silicon-on-insulator) and SOS (silicon-on-sapphire) CMOS ICs are presented. Proposed approaches may be used as an operation of SOI/SOS ICs manufacturing process.

The approach developed in this work allows one to estimate limiting characteristics of single or series of impacts to provide guaranteed further functionality of modern ICs. It may be used also to estimate fault probability after one or series of impacts with known characteristics.

Commercial MOSFET SEB hardness increase method is discussed. Samples subjected to preliminary neutron irradiation show increased SEB hardness than initial ones.

The optimal laser wavelengths for transient ionizing response due to dose rate effect simulation of 0.24 um CMOS SOI devices was found to be 0.56 um for top side irradiation and 1.06 μm for backside irradiation.

This work presents a solution for radiation hardness grading procedure using compact X-ray facility built in probe station, with automated measurement system based on NI PXI platform. The radiation grading procedure can be integrated as additional stage to provide rad-hard option of conventional process. Using the radiation grading procedure as a stage of IC fabrication process, the total ionizing dose (TID) hardness capability was estimated for commercial 65-nm CMOS test structures.

Microbiological and enzyme activities of extrazonal taiga-steppe soils in the lower reaches of the Kolyma River have been studied for the first time. Contrary to north-taiga cryometamorphic soils, predominating in the area, microbial cenoses under herb-sedge petrophytic and grass-sagebrush-herb thermophytic steppes are characterized by features typical for arid soils. The saturation of the soil profile with microorganisms is greater, and the development of actinomycetes is more intensive. The enzyme complex is characterized by high activity of dehydrogenases.

The taxonomic diversity of amoeboid protists was examined in three types of tundra soils in the Kolyma Lowland, namely, a podzolized podbur, a cryozem, and a gleyzem. In total, 27 naked amoeba genera were identified in the analyzed samples. It was shown that the individual soil types house different communities of naked amoebas. The distribution of naked amoebas in the cryozem had two peaks: one in the upper organic horizon and the other at the boundary with the permafrost.

The article is devoted to an automated system for parameters monitoring of the input and output chains of the logic ICs in order to identify its manufacturer. The system based on National Instruments PXI platform. The hardware and software parts of the system, as well as the measurement process and results threat, are observed.

Features of charge formation in SOS structures under irradiation are investigated experimentally. A model that makes it possible to describe the dependence that the kinetics of charge accumulation and relaxation in the Si-Al2O3 system has on the field strength, temperature, intensity, and type of ionizing radiation is suggested. The influence of the two-dimensional character of processes on the charge formation in the SOS MOS devices is investigated.

Device-and-process simulation of the response exhibited by SOS CMOS building blocks to pulsed ionizing irradiation is considered. Computer and laser simulations are conducted. For dose-rate effects, energetically optimal simulation wavelengths are found to range from 0.75 to 0.90 μm.

As a result of analyzing more than 60 types of the modern transceivers ICs, the most sensitive functional units and the critical operation modes upon exposure the space radiation (especifically, TID and SEE effects) were identified

Manifestation of the dose rate effects is strongly depends on the laser polarization direction for the ICs, which technology is less than the laser wavelength. There are several approaches to reduce this influence in deep-submicron ICs.

The article describes the automated complex of parametric and functional control of the wide range of industrial transceivers IC's by using PXI family of National Instruments equipment. The capabilities of the designed system are observed as well as the software.

Observations carried out in 1996-2002 in the northern part of the Kolyma Lowland reveal spatial and temporal regularities in the seasonal thawing of tundra and northern taiga soils. The main factor determining differences in active-layer thickness in zonal tundra landscapes is the texture (mechanical composition) of soil parent material. Summer thaw in sandy soils is 2-3 times deeper than in loamy soils. The distribution of maximum seasonal thaw depth in watersheds and on hillslopes with loamy soils is influenced strongly by climatic zonality, which manifests itself through an increase in the depth of thaw from the arctic tundra to northern taiga. River floodplains, thermokarst depressions (alasy), and polygonal bogs have thinner active layers than adjoining watersheds. A direct correlation exists between seasonal thaw depth and mean summer air temperature in most zonal landscapes. In many cases a tendency for increased thaw depth was observed in the warm summer of 2000-2002. An inverse correlation betwee...

Propositional formulas are represented by real-valued matrices so that their unsatisfiability is proved to be equivalent to the stable nonnegative solvability of linear algebraic systems. The complete calculus for the generation of all nonnegatively solvable linear homogeneous systems is presented as a consequence. Solvability of systems of linear inequalities with real coefficients and Boolean variables is reduced to the satisfiability of some formula. The alternatives theorem is proved concerning the solvability of such systems. The technique of implicit enumeration in the search for solutions both in the systems considered and in a wide range of discrete optimization problems is described. Bibliography: 21 titles.

On the basis of the statistical analysis of the global fields of outgoing long-wave radiation, surface temperature of the ocean, and components of the wind velocity, we analyze five El Nino events observed in 1963–1983. We study the dependence of the global circulation in the lower atmosphere on the behaviour of the temperature of the surface waters and outgoing long-wave radiation in the west part of the tropical zone of the Pacific Ocean. General regularities and specific features of different El Nino events are also analyzed.