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The authors analyze weak seismic activity at the Korobkovo iron ore deposit in the area of the Kursk Magnetic Anomaly. A sensing system in use enabled recording seismic events with a magnitude from –2.5 to –1.4 induced by a large-scale blast. Localization of hypocenteres was accurate to m. The most of origins of the recorded events occurred in the neighborhood of a faulting zone across the zone of mining, and at the interface of bed series. The values of a seismic moment of the events are within of two orders of magnitude N m at an angular origin frequency of 70–600 Hz. The estimated seismic energy ranges from 0.0006 to 1 J. The reduced seismic energy values from to J/(N m) and the low velocities allow categorizing the recorded events as slow earthquakes. [ABSTRACT FROM AUTHOR]

Methods for constructing distributed automation systems for circuit design to calculate the instability of the coordinates of the operating points of the static mode of nonlinear electronic circuits were considered. Two-terminal networks of type R and transmission parameters of dependent sources, as well as characteristics of external influences (temperature, radiation, etc.) are taken as components that change under the influence of external factors. To solve the problem of calculating the instability of the coordinates of the operating points of the static mode of nonlinear electronic circuits, a technique is proposed based on the use of an auxiliary circuit, which is constructed by transposing the description of the original circuit. The features of the organization of serverless and microservice architecture for building circuit design automation systems are analyzed. The multitenant design of a microservice information system environment is described. The mechanism of operation of the service as a service is presented to ensure the operation of the business logic of the server component. [ABSTRACT FROM AUTHOR]

Metamorphic transformations in felsic and mafic rocks in a zone of intense tectonic movements were compared. The object of study is the exhumed part of damage zone of Primorsky fault—main collision suture, which connects the Siberian Craton and the Olkhon Terrane. The studied area is located near the Khorga River. Collected metamorphic rock samples are represented by both "felsic" (plagiogranite-gneiss) and more "mafic" (amphibole–biotite plagiogneiss) rocks. The samples present two different parent rocks contacting each other but differ in chemical composition. The formation of identical metamorphic minerals of the garnet and epidote groups, associated with the processes of high-pressure regional metamorphism and, possibly, later collisional events, is detected in both rock types. The study of the chemical composition of rock-forming minerals provided estimates of the P–T conditions of metamorphism of these rocks by the method of multimineral thermobarometry. It was established that conditions of early metamorphism retain in amphibole-biotite plagiogneiss. Early metamorphism is characterized by high-pressure amphibolite facies of medium temperature next to eclogite facies. The parameters of later metamorphism are recorded in plagiogranite-gneiss, which occurred at higher pressure, but at a lower temperature, within the paragonite–kyanite–zoisite subfacies of the eclogitic facies, bordering on the greenschist facies. Associations of early metamorphism are poorly preserved in plagiogneiss. [ABSTRACT FROM AUTHOR]

Abstract—A laboratory setup was constructed in IDG RAS to investigate the process of shearing the contact of rock blocks of one-meter scale. It was used to investigate deformation processes in a fault with a heterogeneous structure of the sliding interface, which contained strong contact patches—analogs of the asperity in the well-known model of Hiroo Kanamori (Kanamori and Stewart, 1978). It is shown that when a large slip occurs, the rupture, which starts in the zone of maximal deficit of interblock displacement, cuts the segments of the fault with lower effective strength, the latter being decreased in previous deformation events. Those previous events may be "slow" slips with low seismic efficiency. In nature the events that "prepare" the fault interface for a large slip may be smaller earthquakes—foreshocks, or they can be either low frequency earthquakes or slow slip events, both can hardly be detected in seismic records. Thereupon a promising diagnostic indication is the shift of the spectrum of ambient seismic noise to lower frequencies caused by the decrease of fault stiffness. [ABSTRACT FROM AUTHOR]

Abstract—A conceptual state of the art review of the research on fault zone resistance to shear is presented. Recent works are analyzed in the context of the approaches formulated in the authors' presentations made at the Sixth Conference "Triggering Effects in Geosystems." The analysis of the results obtained in the last two or three decades by different research teams shows that frictional properties of a principal slip zone gouge play a determining role for rupture initiation and propagation. Upgrading the methods for processing weak seismicity data to estimate the "slowness" of microearthquakes confined to a fault zone may provide new approaches in fault zone monitoring to derive indirect information on the material composition of a fault slip zone and, thus, on its seismogenic potential. At present, such methods can be useful in the problems of damage reduction from man-made earthquakes. [ABSTRACT FROM AUTHOR]

The paper presents a constructive description of the set of all efficient (Pareto-optimal) investment portfolios in a new setting, where the risk measure named "shortfall probability" (SP) is understood as the probability of a shortfall of investor's capital below a prescribed level. Under a normality assumption, it is shown that SP has a generalized convexity property, the set efficient portfolios is constructed. Relations between the set of mean-SP and the set of mean-variance efficient portfolios as well as between mean-SP and mean-Value-at-Risk (VaR) sets of efficient portfolios are studied. It turns out that mean-SP efficient set is a proper subset of the mean-variance efficient set; interrelation with the mean-VaR efficient set is more complicated, however, mean-SP efficient set is proved to be a proper subset of mean-VaR efficient set under a sufficiently high confidence level. Besides a normal distribution, elliptic distributions are considered as an alternative for modeling the investor's total return distribution. The obtained results provides the investor with a risk measure, that is more vivid than the variance and Value-at-Risk, and with determination of the corresponding set of effective portfolios. [ABSTRACT FROM AUTHOR]

The main problems of configuring the dependences of software products built based on a microservice architecture are described. Examples of a description of the software dependency configuration based on a semantic versioning system are given. A technique to control the dependences of the components of the distributed information systems is considered. A technique for constructing mathematical support for the nonstationary states of nonlinear electronic circuits by the methods of diakoptics is described. It is noted that the absence of inductive connections between individual subcircuits, as well as the placement of control and controlled variables of each dependent source within each subcircuit, is a necessary condition for the possibility of using the proposed technique. It is shown that the practical implementation of the proposed methodology can significantly increase the productivity of the CAD circuit and solve a calculation problem faster, which is especially important in the development of distributed automation systems for designing a circuit. [ABSTRACT FROM AUTHOR]

The article examines the structure of industries by the size of enterprises and evaluates the contribution of different groups of companies in terms of output to the growth of industry output. It is shown that the distribution profile of companies by size in industries is different. Estimates of the contribution of large, medium and small businesses to industry indicators differ significantly depending on a number of institutional factors, including the consolidation of large businesses, the presence of a stable or emerging group of leaders, the affiliation of medium-sized businesses with the largest, as well as the processes of diversification of production going on in industries, in including the "completion" of technological chains with new operations and services. For calculations, we used information from the SPARK-Interfax database for such industries as the oil and gas industry, ferrous and non-ferrous metallurgy, coal, chemical, woodworking, paper, and light industries. On the basis of the estimates obtained, it is proposed, where necessary, to include the factor of the size of companies in the industry and other institutional characteristics in sectoral and macroeconomic forecasts. [ABSTRACT FROM AUTHOR]

Abstract—The paper introduces a new, unique for Russia, meter-scale laboratory setup created in the Institute of Geosphere Dynamics of the Russian Academy of Sciences (IDG RAS) to study the development of different sliding regimes on rock discontinuities. The experimental procedure is described and the results of the first series of tests aimed at studying the formation of different sliding regimes on rock faults are presented. The laboratory fault was a loaded contact of two 75-cm long blocks made of diabase. The fault was filled with granular material (a fault gouge). Normal stresses on the fault can reach 10 MPa. By varying fault gouge composition and loading rate, we reproduced a wide range of sliding regimes: sliding with constant velocity, regular stick-slip, and aperiodic slow slip episodes. It is shown that a variation in the loading rate can cause a significant change in the sliding regime. Intense frictional crushing of gouge grains is detected in the experiments at relatively low normal pressure of 2 MPa. In the case of high-amplitude stick-slip, besides crushing of the gouge material, also structural phase transformations of quartz grains corresponding to a local temperature increase up to 700°C are revealed. A possible set of the problems related to deformation processes in seismogenic fault zones that can be addressed by modeling on such setups—the pre-seismic stage of inelastic behavior of the main fault zone at critical stress—is outlined. [ABSTRACT FROM AUTHOR]

A method of organizing iteration loops in calculating dynamic modes of large electronic circuits based on a decomposition of the modeled circuit into subcircuit components is considered. This method considerably reduces the time required for the interaction of system's users with the network, so the efficiency of the used software is improved significantly, which is especially important for the construction of service-oriented computer-aided design systems. [ABSTRACT FROM AUTHOR]

Abstract—The basic requirements for software for building distributed automation systems for circuit design have been determined. The distinctive features of the architectural style of building distributed systems based on RESTful web services are described. Methods for grouping the components of the simulated circuit based on the type of connected pole are described. A form of writing an equation for a modeled scheme is proposed with the possibility of using both explicit and implicit forms for describing component equations. Two methods are proposed for the implementation of the computational process of calculating the characteristics of an electronic circuit based on different principles. formation of mathematical description in complex and linear forms. The advantages and disadvantages of the described methods, as well as algorithms for the formation of a mathematical description are given. [ABSTRACT FROM AUTHOR]

A fast numerical algorithm for calculating the given instability of the zero level of DC amplifiers is considered. Traditional methods for calculating the instability of nonlinear electronic circuits require repeated calculations of the stationary mode of the simulated nonlinear circuit, followed by the calculation of the sensitivity of the values of the coordinates of the operating points to variations in the parameters of the components. In contrast to them, the method proposed in this article is based on performing a single linearization of the nonlinear characteristics of the components only at the initial stage of solving the problem. At the subsequent stages of solving the problem, the linearized representation of the components is used to calculate the given instability under the influence of external influences and the technological spread of parameters during the serial production of the developed circuit. [ABSTRACT FROM AUTHOR]

Abstract—Granular media determine the dynamics of many natural systems including faults in the Earth's crust. The paper addresses the laboratory study of shear deformation of a model fault simulated by a layer of granular material located between rock blocks. A model fault is a complex dynamic system characterized by the presence of bifurcations and fast and slow slips may take turn aperiodically during deformation. The sliding of the rock blocks is accompanied by the generation of acoustic emission pulses (AEs) which are identified based on the Akaike information criterion. The dynamics of AEs reflects the evolution of mechanical properties of the fault. In the flow of AEs, the subsets with different rise time/amplitude values (RA-values) and different scaling relations are identified. Applying the random forest machine learning algorithm to the analysis of AE catalogue demonstrates the possibility of determining the velocity of fault sliding and the time to both fast and slow slips. The nucleation of a certain slip mode is predetermined by the self-organization processes taking place in the central zone of a fault, and the characteristics of the AE reflect these processes. The proposed approach to the estimation of fault sliding parameters can be promising for the design of new methods for monitoring stressed massifs at mining. [ABSTRACT FROM AUTHOR]

The article assesses the possibilities of including institutional factors in macroeconomic and sectoral forecasts. It has been substantiated that a number of institutional features associated with the concentration of business in sectors of the economy and its consolidation around the leading group of companies in the market may reflect qualitative changes in the architecture of markets, the strengthening of explicit or implicit dominance, the formation of institutional barriers and traps. At the same time, the outstripping growth of large business significantly affects the industry dynamics and structural shifts, but is not synchronized across industries and is uneven in time. An approach is proposed for comparing the processes of business consolidation in the sectors of the Russian consumer market. Quantitative calculations have been performed, confirming the hypothesis of the importance of institutional factors that enhance the influence of large business in industries on the dynamics of their indicators. An assumption is made about a qualitative change in the sensitivity of markets to government regulation measures, depending on the stability of their architecture. [ABSTRACT FROM AUTHOR]

The compaction of initial powders, the bending strength, and the microhardness of 21R sialon ceramics obtained by hot pressing have been studied experimentally. It is found that the Sm2O3 sintering additive substantially reduces the annealing temperature and enhances the properties of the ceramics. The samples of 21R sialon ceramics without additives, which are prepared by annealing at 1950°C, have a density of 3.01 g/cm3, a bending strength of 240 ± 15 MPa, and a Vickers microhardness of 16.2 ± 0.4 GPa; the samples of 21R sialon ceramics with 2.5 wt % Sm2O3, which are annealed at 1750°C, are characterized by a density of 3.39 g/cm3, a bending strength of 315 ± 16 MPa, and a Vickers microhardness of 21.9 ± 0.2 GPa. It is shown that Sm2O3 reacts with 21R sialon in the temperature range of 1600–1700°C to form the 27R sialon and SmAlO3 impurity phases. In the samples annealed at 1750°C, the 27R sialon and Sm–sialon (Sm3Si2.5Al3.5O12.5N1.5) impurity phases are detected. [ABSTRACT FROM AUTHOR]

In this paper we conduct a phenomenological study for the search of evidence for the intrinsic charm mechanism in double production at the COMPASS experiment using the CERN beam at 190 GeV/c. Estimations on pair cross-sections and kinematic distributions are given for different production mechanisms. We also re-review the double production data provided by the NA3 experiment using the CERN beam at 150 and 280 GeV/c with incident on a platinum target. [ABSTRACT FROM AUTHOR]

Different types of coordination numbers in molecular crystals are discussed. Monosystem crystal structures of hydrocarbons are used as an example to study the relation between parameter R of a Delaunay system, and the coordination numbers, topological types, and intermolecular interaction energies. [ABSTRACT FROM AUTHOR]

The problem of designing an optimal insurance strategy in a new multistep insurance model is investigated. This model introduces stepwise probabilistic constraints (Value-at-Risk constraints) on the insurer's capital, i.e., probabilistic constraints on the insurer's capital increments during one step. As the objective functional the mathematical expectation of the insurer's final capital is used. The total damage to the insurer at each step is modeled by the Gaussian distribution with parameters depending on a risk sharing function selected. In contrast to traditional dynamic optimization models for insurance strategies, the approach proposed below takes into account stepwise constraints; within this approach, the Bellman functions are constructed (and hence the optimal risk sharing is found) by simply solving a sequence of static insurance optimization problems. It is demonstrated that the optimal risk sharing is the so-called stop-loss insurance. [ABSTRACT FROM AUTHOR]

An important stage in the design of electronic circuits of various classes and purposes is the calculation of the zero-level instability of a developed device under the influence exerted on the parameters of its components by external disturbances (variations in temperature, humidity, pressure, radiation, etc.), as well as by technological variations in these parameters in the course of serial manufacturing. A mathematical description of the problem of calculating the zero-level instability of an electronic circuit is constructed for the common case when the coordinates of operating points of all circuit components are known and the task is to find their deviations under variations in the parameters of circuit components caused by external disturbances, as well as under technological variations in these parameters in the course of manufacturing. An advantage of the proposed technique is that it avoids multiple calculations of a nonlinear circuit and its sensitivity to parameter variations, instead dealing with a mathematical description of the linearized circuit, which is used to determine the deviations of variables from their initial stationary values. As a result, the amount of computational operations is dramatically reduced and the computation time is reduced as well, which is especially important for solving optimization problems in electronic circuit design. [ABSTRACT FROM AUTHOR]

A statistical analysis of molecular coordination numbers for the crystal structures of 316 bisystem hydrocarbons with Z″ = 2 is carried out. The relationship between coordination numbers, the topological type of networks, and the intermolecular interaction energy calculated by the 6-exp method is studied. It is found that critical networks most often do not correspond to the criteria of minimum networks, i.e. a set of contacts generating the crystal structure is redundant for the structural class. The geometric and energy criteria of the critical network are shown to yield inconsistent results in the structures of bisystem hydrocarbons more often than in monosystem ones. [ABSTRACT FROM AUTHOR]

Various types of coordination numbers in molecular crystals are discussed. The relationship between parameter R of the Delone system, coordination number (CN), topological type, and the intermolecular interaction energy is studied on the example of crystal structures of centrosymmetric hydrocarbons. The first coordination sphere of a molecule takes 86.2±1.6% of the lattice energy; the interactions providing molecular arrangement take at least 50% of the lattice energy for CN ≥ 6. The nets characterizing the framework of intermolecular interactions in this series of structures tend to the lowest cyclomatic number of the quotient graph. [ABSTRACT FROM AUTHOR]

The existing profiles of internal screw channels are reviewed. Formulas are proposed for the static error in the channel depth due to elastic deformation of the walls of the cylindrical shell in cutting. (Shells of steel 45 and BrAZh9-4 bronze are considered.) An approach is outlined to determining the static error in machining helical channels by a mandrel with one and three cutting teeth. The error in the cutting depth is plotted as a function of the cutting speed with different wall thickness of the cylindrical shell. [ABSTRACT FROM AUTHOR]

We consider methods to construct mathematical models for the automation of circuit design that implement the calculations of the parameters and the structure of the circuit connections of the components of the developed electronic device displayed by its graphic scheme. We note that the modeling of frequency properties of an electronic circuits in a frequency range is among the main problems of circuit design. Within this range, the frequency characteristics of the circuit are computed multiply to find the admissible or optimum values of the parameters of the components used in the designed electronic circuit. It is shown that two approaches to resolve such a problem are possible. The first approach is based on the description of the simulated circuit by complex matrices at each frequency f [kf] of the given frequency range with the preliminary calculation of the operator s = (0.0, 2 × 3.14 f [kf]). A substantial disadvantage of this approach is the necessity to form a mathematical description of all the circuit components at each frequency. The second approach is based on the representation of the complex matrix of the scheme in the bilinear form W = A + sB, where A and B are real frequency-independent matrices. It is shown that, in a number of cases, we have to present the equations of frequency-dependent components in an explicit form to implement such an approach, while this is possible only if the scheme is described in selected coordinate bases such that this possibility is foreseen for them. A technique is proposed to describe the simulated circuits based on a modified basis of the nodal potentials, providing the possibility to use both explicit and implicit forms to specify the component equations. It is shown that the bilinear form of the circuit description, based on the modified basis, substantially improves the efficiency of computing the frequency characteristics because the fixed frequency-independent matrix components of the circuit are used at each frequency. [ABSTRACT FROM AUTHOR]

Abstract—The definitions of the critical contact and critical energy coordination number (CECN) of a molecular crystal are introduced. Some characteristics of the critical contact in the diagram of intermolecular interaction energies are discussed. The molecular coordination number (MCN) and critical coordination number (CCN) in a series of crystalline structures of homomolecular monosystem aliphatic α,ω-diols are calculated. [ABSTRACT FROM AUTHOR]

We solve a problem of optimal risk control in the static model by choosing an admissible insurance policy, where the objective functional is the so-called Markowitz utility functional, i.e., a functional that depends only on the mean value and standard deviation of the insurer's final capital after an insurance transaction. Interests of the insurer are taken into account by introducing probabilistic or, more precisely, quantile constraints (value at risk constraint) on the final capital of the insurer, using a normal distribution to model the distribution of total damage. Additionally, we impose a restriction with probability one on the risk taken from an individual policy holder. Optimal from the point of view of the insurer is the so-called stop-loss insurance. We find explicit forms of conditions for refusing an insurance transaction. We give an example that illustrates the proven results in case of an exponential distribution of claim size. [ABSTRACT FROM AUTHOR]

The use of the Holstein breed's genetic potential has enabled the creation of a new Ural Black-and-White cattle type to improve the indigenous breeds. The Ural region cattle population consists of eight breeds. The Black-and-White cow makes up 81.9%. The cow milk production is 6237 kg milk. The mass fractions of milk fat and protein are 3.88 and 3.13%, respectively. The highest milk yield of 7352 kg milk is recorded in the Holstein cows. The purebred and fourth generation animals represent 92–100% of the population in the oblasts and republics within the region. In addition, all the cattle on the farms in the Tyumen, Kurgan, and Chelyabinsk oblasts and in the Primorsky krai are purebred; eighty percent of these purebred animals are classed as the Elite Record (Super Elite) and Elite cattle. Therefore, the high-class cattle herds are built in the Ural region. [ABSTRACT FROM AUTHOR]

The current status of the large decameter radio telescope UTR-2 (Ukrainian T-shaped Radio telescope) together with its VLBI system called URAN is described in detail. By modernization of these instruments through implementation of novel versatile analog and digital devices as well as new observation techniques, the observational capabilities of UTR-2 have been substantially enhanced. The total effective area of UTR-2 and URAN arrays reaches 200 000 m, with 24 MHz observational bandwidth (within the 8-32 MHz frequency range), spectral and temporal resolutions down to 4 kHz and 0.5 msec in dynamic spectrum mode or virtually unlimited in waveform mode. Depending on the spectral and temporal resolutions and confusion effects, the sensitivity of UTR-2 varies from a few Jy to a few mJy, and the angular resolution ranges from ~ 30 arcminutes (with a single antenna array) to a few arcseconds (in VLBI mode). In the framework of national and international research projects conducted in recent years, many new results on Solar system objects, the Galaxy and Metagalaxy have been obtained. In order to extend the observation frequency range to 8-80 MHz and enlarge the dimensions of the UTR-2 array, a new instrument - GURT (Giant Ukrainian Radio Telescope) - is now under construction. The radio telescope systems described herein can be used in synergy with other existing low-frequency arrays such as LOFAR, LWA, NenuFAR, as well as provide ground-based support for space-based instruments. [ABSTRACT FROM AUTHOR]

The results of the first observations of solar sporadic radio emission within 10 - 70 MHz by the Giant Ukrainian Radio Telescope (GURT) are presented and discussed. Observations in such a wide range of frequencies considerably facilitate the registration of harmonic pairs. The solar U-burst harmonic pair observed on 8 August 2012 is analyzed. The burst key features were determined. Among them, the time delay between the fundamental and harmonic emissions was of special interest. The fundamental emission was delayed for 7 s with respect to the harmonic emission. A model for explaining the occurrence of such a delay is proposed, in which the emission source is located inside a magnetic loop containing plasma of increased density. In this case, the delay appears due to the difference in group velocities of electromagnetic waves at the fundamental and the harmonic frequencies. [ABSTRACT FROM AUTHOR]

We find optimal (from the insurer's point of view) strategies for insurance and reinsurance in a controllable Cramér-Lundberg risk process that describes the capital dynamics of an insurance company over an extended time interval. As the optimality criterion being minimized, we use the stationary variation coefficient, taking into account additional constraints on residual risks for both insurers and reinsurer. We establish that it is best to use stop-loss reinsurance with an upper limit and insurance which is a combination of a stop-loss strategy and franchise. We derive equations that define optimal strategy parameters. [ABSTRACT FROM AUTHOR]

The scintillation characteristics of detectors based on scintillators produced by hot vacuum pressing of activated p-terphenyl plates grown by melt crystallization have been investigated. The possibility of improving the scintillation characteristics of the detectors by vacuum pressing of the starting material and perfection of the optical system of polycrystalline scintillators is shown. [ABSTRACT FROM AUTHOR]

We have developed an active dipole that is intended for use in new generation low frequency array applications. The preamplifier of the active dipole has very high linearity (input IP2 = 70 dBm, input IP3 = 31 dBm) and low noise temperature (100-360 K). The frequency dependence of the dipole impedance and the match between the dipole and preamplifier have been optimized to achieve Galactic noise limited operation. The ratio between the antenna temperature due to Galactic noise and the noise temperature of the preamplifier is 10 ± 1.5 dB over the whole 10 to 70 MHz range. The total cost of the active cross-dipole is 220 euro. [ABSTRACT FROM AUTHOR]

A design of an angle shutoff valve assembled by the group assembly (subassembly) method is proposed; an advanced method of molding (shaping) sealing surfaces of various types of detachable joints by plastic deformation is described; the results of simulation of crumpling of the ring projection (asperity) before molding of sealing band are reported; the results of full-scale experimental investigations, which confirmed the basic results of computer simulation using ANSYS program (software), are cited; the sealing capacity of cone-cone and plane-plane type of threaded metal-to-metal joints, whose sealing surfaces were produced by plastic deformation, is determined; the effectiveness of sealing pairs, whose sealing surfaces were formed by plastic deformation, is shown; ways of solving technological problems faced in producing valve parts are indicated; conclusions are formulated. [ABSTRACT FROM AUTHOR]

We consider the optimal choice problem by a risk-bearing function for an insurer to divide risks between him and his clients in a dynamic insurance model, the so-called Cramer-Lundberg risk process. In this setting, we take into account restrictions imposed on policyholder risks, either on the mean value or a constraint with probability one. We solve the optimal control problem on an infinite time interval for the optimality criterion of the stationary coefficient of variation. We show that in the model with a restriction on average risk the stop-loss insurance strategy will be most profitable. For a probability one restriction, the optimal insurance is a combination of a stop-loss strategy and a deductible. We show that these results extend to a number of problems with other optimality criteria, e.g., the problems of maximizing unit utility and minimizing the probability of deviating from the mean value. [ABSTRACT FROM AUTHOR]

Current-voltage and light-current characteristics of light-emitting InGaN/GaN heterostructures and blue and white light-emitting diodes before and after irradiation with fast neutrons and electrons are analyzed. A generalized model of a light-emitting heterostructure, with an optically active region with one or several quantum wells in the compensated layer, is suggested. The constants of nonradiative lifetime degradation of blue and white light-emitting diodes under irradiation are estimated. [ABSTRACT FROM AUTHOR]

The paper is devoted to solving problems of optimal choice of client’s risk bearing by the insurer at the level insurer-client and at the level insurer-reinsurer. It was shown that in the model of additional restrictions, the most profitable for the insurer will be the refusal from reinsurance and application of stop-loss insurance strategy. In the problem that takes the restriction on insurer’s risk into account, reinsurance of excess of loss and insurance that is a combination of the stop-loss strategy and deductible are optimal. Necessary and sufficient conditions of optimality of parameters of the stated strategies are obtained; an example illustrating the proved results in case of exponential utility functions is given. [ABSTRACT FROM AUTHOR]

The coordination of pyrylium and thiopyrylium cations with borabenzene was studied by DFT [B3LYP/6-311++G(d,p)] calculations. The structures of charge-transfer molecular complexes formed by the aromatic ions were predicted. The stabilization is due both to electron density transfer and to covalent bonding. [ABSTRACT FROM AUTHOR]

The effect of counterions on the stabilization of aromatic pyrylium cation, a heterocyclic analog of benzene, was examined by ab initio [MP2(full)/6-311++G**] method and density functional theory [B3LYP/6-311++G(d,p)(6d,10f)]. Structures of the charge-transfer molecular complexes formed by interaction of pyrylium cation with counterion are predicted. The principal role of the counterion in the stabilization of the pyrylium cation aromatic system is demonstrated. The stabilization results from both electron density transfer and covalent bonding. [ABSTRACT FROM AUTHOR]

Polysilicon/silicon-dioxide/polysilicon structures (double polysilicon) are grown by deposition of amorphous silicon followed by thermal oxidation and a final polysilicon deposition process. Correlation between the appearance of silicon nano-structures and surface morphology formed during the amorphous silicon deposition stage and the electrical characteristics of the double poly capacitor have been investigated. It is shown that the process parameters have a pronounced effect on the morphological properties of the film surface. Nanometric size asperities form during the amorphous silicon deposition stage. The density and height distribution of these asperities were found to depend on deposition temperature. Thermal oxidation of the amorphous layer resulted in the growth of a top oxide layer and crystallization of the bottom silicon film. This process results in an overall increase of the surface roughness and a pronounced decrease in the height of the nano-asperities. By HF-etching the oxidized film, the surface of the polycrystalline silicon is exposed. Following this etching process, the surface roughness increases, whereas the density and height of the nano-asperities decrease. A correlation between the height of asperities on the bottom amorphous silicon film (as well as roughness of this film) and the breakdown voltage of the double poly was found. [ABSTRACT FROM AUTHOR]

An effective wide-band (10 to 60 MHz) active antenna element has been developed. The cost of one short (3 m), thin dipole with built-in amplifier and metal construction is less than 45 euro. It was shown both theoretically and experimentally that the upper limiting frequency is at least 60 MHz, the dynamic range is 90 dB/μV and the share of the amplifier noise to the background antenna temperature is about 10%. The developed active dipole was tested by building a 30-element antenna array and comparing its parameters with one of the subpart of the UTR-2 radio telescope having passive dipoles of 8.6 m in length and 1.8 m in diameter. The 3C461 ionospheric scintillation spectra observed in the experiments show that the sensitivities and noise-immunities of both antennas are close. This proves the availability using of a short cheap active dipole in new generation giant radio telescopes. [ABSTRACT FROM AUTHOR]

An improved analytical method for airborne lead traces is reported. It is based on using a Venturi scrubber sampling device for simultaneous thin-film stripping and droplet entrapment of aerosol influxes. At least threefold enhancement of the lead-trace pre-concentration is achieved. The sampled traces are analyzed by square-wave anodic stripping voltammetry. The method was tested by a series of pilot experiments. These were performed using contaminant-controlled air intakes. Reproducible calibration plots were obtained. The data were validated by traditional analysis using filter sampling. LODs are comparable with the conventional techniques. The method was successfully applied to on-line and in situ environmental monitoring of lead. [ABSTRACT FROM AUTHOR]

Successful coupling of imaging microscopy with Fourier transform spectrometry provides a new methodological approach. This was applied to the direct analysis of particulate deposits of polycyclic aromatic hydrocarbons (PAHs). The fluorescence signals of single microscopic particulates were found to be proportional to their mass, obtained from the corresponding HPLC results. Special fluorescence characteristics related to individual particle analysis were studied. The sensitivity of the proposed method to PAHs in soil is in the sub-ppb range, similar to HPLC results. Analysis of inhomogeneous PAH-particulates was demonstrated, as well as the resolution of photochemical products of PAHs. The effects of particulate orientation relative to the detector upon quantification are discussed. [ABSTRACT FROM AUTHOR]

The relationship between blood group alleles inheritance and the first milk yield of cows per herd of heifers was studied on 1655 individuals. Milk production performance of heifers that received the analyzed allele from a father, a mother, or without regard to the mode of inheritance was compared with the same parameter of those animals that did not have the analyzed allele. The allele E′3F′2G′O′G″ was found to be an immunogenetic marker of high milk yield. The difference in milk yield between carriers of this allele and herdmates was significant ( P < 0.001) and equaled 384 kg of milk. The most common alleles in the population G2Y2E′1Q′ and I2 were neutral with regard to milk yield. The presence of alleles E′1, G′′, and O3J′2K′O′ in a genotype was associated with reduced milk yield in Ural type cattle. [ABSTRACT FROM AUTHOR]