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[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT The article presents the results of development and research of a mathematical model of wind power station connected to the electric system and multi-level, mobile load. It is assumed that the load is variable in time and location. The response of the system to various perturbations is studied, the technique of selection of parameters for automatic control of external rotor resistance is considered, the necessity of introducing a voltage stabilization circuit is justified. The advantages of the power supply circuit using a wind power station in the presence of wind power fluctuations are shown. Keywords: wind power station, asynchronous generator, mathematical model, mobile load, recuperation.

Results of numerical modeling of the gas dynamics ofmaterial in the envelopes of T Tauri binary stars with a small component mass ratios (q = 0.08) are reported. In such systems, the less massive component is moving at a supersonic velocity, and the more massive component can move with either a subsonic or supersonic velocity. The modeling results show that the morphology of the flow changes substantially in the transition from supersonic to subsonic motion of the massive component. In particular, one of the two bow shocks vanishes, flows ofmaterial in the system are redistributed, and the characteristics of the accretion disks change. In addition, the effect of the change in the accretion mode on the evolution of the binary system and the possibility of recovering some parameters of the system from observational manifestations of shocks in the circumstellar envelope are considered.

Precise measurements of the branching ratios for the flavor-changing neutral current decays K → π ν ν ¯ can provide unique constraints on CKM unitarity and, potentially, evidence for new physics. It is important to measure both decay modes, K + → π + ν ν ¯ and K L → π 0 ν ν ¯ , since different new physics models affect the rates for each channel differently. The NA62 experiment at the CERN SPS will measure the BR for the charged channel to better than 20%. The BR for the neutral channel has never been measured. We are designing the KLEVER experiment to measure BR( K L → π 0 ν ν ¯ ) to ∼20% using a high-energy neutral beam at the CERN SPS. The boost from the high-energy beam facilitates the rejection of background channels such as K L → π 0 π 0 by detection of the additional photons in the final state. On the other hand, the layout poses particular challenges for the design of the small-angle vetoes, which must reject photons from K L decays escaping through the beam exit amid an intense background from soft photons and neutrons in the beam. We present findings from our design studies, with an emphasis on the challenges faced and the potential sensitivity for the measurement of BR( K L → π 0 ν ν ¯ ).

Nowotny chimney ladder (NCL) phases are intermetallic compounds formed by transition metals and metals of groups 13 and 14. This family can be expanded by combining two p-elements from different groups with those transition metals, for which the corresponding binary NCL phases are unknown. In this paper, we present three new compounds in the V-Al-Ge, Nb-Al-Ge, and Nb-Ga-Ge systems related to the TiSi2 structure type (Sp. Gr. Fddd) obtained with the standard ampule technique. The crystal structures of the new compounds were determined using synchrotron powder X-ray diffraction data. A transition to the CrSi2 structure type was detected upon changing the composition from VAl0.72(2)Ge1.28(2) to VAl1.534(3)Ge0.466(3). According to the 18&ndash, n rule, all the compounds are metallic conductors, which was supported by the electronic structure calculations. It was shown that the expected energy gap located above the Fermi level in the vanadium-based NCL compound collapsed into a pseudogap upon the replacement of V by Nb.

We present the results of simultaneous spectroscopic and photometric observations of the cataclysmic variable star (hereafter CVs) V455 Andromedae, belonging to the WZ Sge sub-class, in quiescence. Using the spectroscopic data we computed time-resolved Doppler tomograms of the system demonstrating its behavior at different orbital phases. In the tomograms one can see the periodic brightening of different regions within one orbital cycle. We interpret this brightening as being due to the interaction of four phase-locked shock waves in the disk with a specific internal precessing density wave that develops inside the disk, because of the tidal influence of the secondary star, and this density wave propagates up to the disk's outer regions. The shock waves, located in the outer regions of the disk, are: two arms of the tidal shock; the "hot line", a shock occurring in the region of the interaction between the stream from the $L_{1}$ point and the disk; and a bow-shock, occurring ahead of the disk due to its orbital supersonic motion in the circumbinary gas. When the outer part of the density wave in its precessional motion reaches a shock wave the local density grows, which amplifies the shock (by increasing $\rho V^{2}/2$). This results in an additional energy release in the shock and can be observed as a brightening. Analysis of the tomographic results and the photometric data shows that two main sources contribute to the light curves of the system: the radiation of the "hot line" and the bow-shock gives us two major orbital humps, located approximately at the orbital phases $\phi=0.25$ and $\phi=0.75$; the amplification of the four shock waves may give us up to four "superhumps" shifting over the light curve with the precessional period. These two effects, when overlapping, change the shape of the light curves, shift the hump maxima, and they sometimes produce more than two humps in the light curve. We should emphasize that when saying "superhumps" we imply an effect that is observed in quiescent light curves of WZ Sge stars, as opposed to ''classical'' superhumps usually observed in outbursts.

Since 2014, a SLAC-Aarhus-Ferrara-CalPoly collaboration augmented by members of ANL and MIT has performed electron and positron channeling experiments using bent silicon crystals at the SLAC End Station A Test Beam as well as the FACET accelerator test facility. These experiments have revealed a remarkable channeling efficiency of about 24% under our conditions. Volume reflection is even more efficient with almost the whole beam taking part in the reflection process. A positron experiment demonstrated quasi-channeling oscillations for the first time at high beam energy. In our most recent experiment we measured the spectrum of gamma radiation for crystal orientations covering channeling and volume reflection. This series of experiments supports the development of more advanced crystalline devices capable e.g. of producing narrow-band gamma rays with electron beams or studying the interaction of the electrons with the wakefields generated in the crystal at high beam intensity.

The article describes the principle of constructing and implementing a software and hardware for measuring the constant magnetic field of the circular electromagnet in the IHEP U-70 synchrotron. Algorithms for signal processing and software description are given., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

We measured a considerable increase of the emitted radiation by 120 GeV/c electrons in an axially oriented lead tungstate scintillator crystal, if compared to the case in which the sample was not aligned with the beam direction. This enhancement resulted from the interaction of particles with the strong crystalline electromagnetic field. The data collected at the external lines of the CERN Super Proton Synchrotron were critically compared to Monte Carlo simulations based on the Baier-Katkov quasiclassical method, highlighting a reduction of the scintillator radiation length by a factor of 5 in the case of beam alignment with the [001] crystal axes. The observed effect opens the way to the realization of compact electromagnetic calorimeters or detectors based on oriented scintillator crystals in which the amount of material can be strongly reduced with respect to the state of the art. These devices could have relevant applications in fixed-target experiments, as well as in satellite-borne γ telescopes. We measured a considerable increase of the emitted radiation by 120 GeV/c electrons in an axially oriented lead tungstate scintillator crystal, if compared to the case in which the sample was not aligned with the beam direction. This enhancement resulted from the interaction of particles with the strong crystalline electromagnetic field. The data collected at the external lines of CERN SPS were critically compared to Monte Carlo simulations based on the Baier Katkov quasiclassical method, highlighting a reduction of the scintillator radiation length by a factor of five in case of beam alignment with the [001] crystal axes. The observed effect opens the way to the realization of compact electromagnetic calorimeters/detectors based on oriented scintillator crystals in which the amount of material can be strongly reduced with respect to the state of the art. These devices could have relevant applications in fixed-target experiments as well as in satellite-borne gamma-telescopes.

Results of comparison of Gaia DR2 parallaxes with data derived from a combined analysis of 2MASS (Two Micron All-Sky Survey), SDSS (Sloan Digital Sky Survey), GALEX (Galaxy Evolution Explorer), and UKIDSS (UKIRT Infrared Deep Sky Survey) surveys in four selected high-latitude | b | &gt, 48&deg, sky areas are presented. It is shown that multicolor photometric data from large modern surveys can be used for parameterization of stars closer than 4400 pc and brighter than g S D S S = 19 . m 6 , including estimation of parallax and interstellar extinction value. However, the stellar luminosity class should be properly determined.

Приведен обзор проблем и задач, связанных с определением параметров функции звездообразования для двойных систем. Описан подход к исследованию начальных распределений двойных звезд по фундаментальным параметрам путем решения обратной задачи. We review tasks and problems related to determination of parameters of star formation function for binary systems. The approach toward investigation of initial distributions of binary stars over fundamental parameters via solving inverse problem is described. Работа выполнена при частичной поддержке гранта РФФИ 15-02-04053 и программы Президиума РАН № 28 «Космос: исследования фундаментальных процессов и их взаимосвязей».

Results of investigations of adhesives and compounds based on epoxy resins modified with low-molecular rubbers are presented. A series of epoxy-rubber compositions with improved physicomechanical characteristics and operational properties are developed. Examples of solutions of engineering challenges using high-molecular synthetic adhesive systems are given.

Fluorescence and IR absorption spectra are taken of coatings obtained by applying polyamide 6 powder on a steel substrate heated above the polymer melting point and subsequently cooling to room temperature. It follows from the coating spectra that the energy of a π* → n transition in the C—O bonds of polyamide decreases. Simultaneously, the maximum of a band assigned to the deformation vibrations of N—H bonds shifts toward longer wavelengths. These effects are explained by the formation of coordination bonds between Fe2+ ions having diffused from the steel into the polymer and nitrogen atoms entering into polyamide 6 molecules. As a result, a coordination-compound-saturated diffusion layer up to 100 µm thick arises near the steel surface. Coordination compounds squeeze the framework of the polyamide 6 molecule roughly by 0.06%. Eventually, a polyamide layer that is stronger than the surroundings appears at the polyamide 6—steel interface.

Powders of polyamides PA 6 and PA 6.6 were deposited on the surface of steel heated to temperatures above melting points of these polymers. Strong wear-resistant coatings were formed on the surface after cooling. Measurements showed that, as the thickness of coatings decreases, their wear resistance increases. In order to reveal the nature of this phenomenon, stresses in polymer molecules were measured in coatings of mentioned polymers by infrared spectroscopy. It was found that the skeleton of polyamide molecules in coatings is compressed. This effect was explained by the formation of coordination compounds between nitrogen atoms of polyamide molecules and Fe2+ ions. It was revealed that the compression of the skeleton of molecules leads to an increase in their strength and wear resistance of coatings.

A CRYSTAL simulation code for particle tracking in crystals is introduced. Its essence consists in both adequate and fast sampling of proton trajectories in crystals which is crucial for both correct description of experiments and quantitative prediction of new effects. The H8 single-pass experiment at the CERN SPS as well as 7 TeV proton deflection by a bent crystal at the LHC are simulated. We predict the existence of dechanneling peaks corresponding to the planar channeling oscillations as well as describe the possibility of their observation at high energies, specifically at the LHC energy. An effect of excess over the amorphous level of ionization losses in the channeling mode was also found at 7 TeV.

A mechanism for the formation of humps in the light curves of WZ Sge cataclysmic variables is proposed, based on the results of three-dimensional simulations of the gas dynamics in the V455 And system. Analysis of the computed flow structure shows the formation of an accretion disk and four shocks in the system, located at the outer edge of the disk. Moreover, a precessional spiral density wave forms in the accretion disk, which is essentially at rest in the observer’s frame. As a consequence, all four shocks (two arms of a tidal shock, a “hot line,” and an outgoing shock) pass through the location of the precessional density wave during each rotation of the disk. The interaction of the precessional spiral density wave with the shocks leads to an additional local density enhancement in the vicinity of the shocks. This strengthens the shocks and enhances the energy release at the shock fronts; this, in turn, should increase the brightness of the system, which could be observed as a hump in the light curve. The shift of the humps observed in the V455 And light curve in orbital phase as a function of the observing epoch is easy to explain in this picture, as a consequence of the difference in the velocities of the retrograde precession of the density wave and the orbital rotation of the binary. The variation in the observed number of humps can be explained by the presence of four, rather than two, strong shocks in the flow pattern and the conditions for their visibility at a given observing time.

The structure of the water masses in the region Argentine Islands archipelago was first investigated according to the data detailed oceanographic survey, which was conducted during the period of the 17th Ukrainian Antarctic Expedition (2012-2013). Formation of а three-layer structure of water masses in summer were observed in the Penola Strait, the cold intermediate layer of negative temperature was found for the first time . This layer separates relatively warm and significantly more salty deep-waters from the warmed up in summer conditions and freshened surface wa­ters. Higher salinity of deep waters does not allow to go down of the cold waters of the intermediate layer оn the great­er depths, so they are spread in the subsurface horizons. Summer the Antarctic cold intermediate layer (ACIL) is de­fined as а layer of negative temperatures, the temperature in the core is lower than -0.35 °С. ACIL located in the Strait of Penola in а layer of seasonal jump in density at а depth of 25-80 meters. Outlet glaciers are the source of generation ACIL оn western shelf of the areas Antarctic Peninsula. The volume-statistical analysis the Т, S-diagrams showed the existence of transfer to the water area of Argentine Islands of the intermediate-deep waters of the Вау Margaret, which is located to the south of the archipelago.

The structure of the water masses in the region of the archipelago Argentine islands was investigated ac­cording to the data oceanographic survey. The survey consisted of 60 stations of inter-island zone archipelago and three orthogonal cuts (10-12 stations) in the deep Straits of Penola. The two-layer vertical structure with desalinated water and warm surface layer and salty and cold water of bottom layer was observed in the area of inter-island. The thermocline is located at depths of 20-30 m in the northern and southern parts of the island area. The thermocline is located at a depth of 30-40 m in a more shallow central part of the island area, because there existed favorable condi­tions for spring-summer warming. Analysis of form T, S-curves allows to conclude that the monitoring space-time structure of the thermohaline field interisland the waters area enough make in a single point. The outlet glaciers of the Antarctic Peninsula in the summer generate large volumes of meltwater and create conditions for the formation of a three-layer structure of water. Cold intermediate layer separates relatively warm and more salty deep-water from warmed and freshened in summer conditions of surface waters. Analysis of T, S-diagrams of water of different regions of the western shelf of the Antarctic Peninsula led to the conclusion of a transfer of intermediate and deep waters from the south.

We have investigated the time dependences of the strength of adhesive bonds between polymers (epoxy adhesive and polyamide) and steel 45 at various temperatures. These dependences have been determined based on the rates of two opposite processes, viz., an increase in strength due to the formation of coordination bonds between polymer molecules and Fe2+ ions and a decrease in strength due to ruptures of adhesive or polyamide molecules under the effect of internal stresses. The values of activation energy of these processes have been determined.

Processes of dynamic formation of the coalitions in tasks of mortgage lending are considered, an influence of uncertain factors on functioning and efficiency of the organization of the coalition of borrowers is investigated, the corresponding mathematical models are written out, results of computing experiments are given.

The problems of decision-making by the coalition of borrowers are considered. The main participants of housing crediting are borrowers and creditors. To find a compromise between contract savings, mortgage lending, state support the mathematical model for financial processes is used. The optimizing task for calculation of mortgage contracts parameters in the case of using the casual mechanism to the choice participant who is the recipient of the credit is formulated.

We report on the first experimental observations of quasichanneling oscillations, recently seen in simulations and described theoretically. Although above-barrier particles penetrating a single crystal are generally seen as behaving almost as in an amorphous substance, distinct oscillation peaks nevertheless appear for particles in that category. The quasichanneling oscillations were observed at SLAC National Accelerator Laboratory by aiming 20.35 GeV positrons and electrons at a thin silicon crystal bent to a radius of $R=0.15\text{ }\text{ }\mathrm{m}$, exploiting the quasimosaic effect. For electrons, two relatively faint quasichanneling peaks were observed, while for positrons, seven quasichanneling peaks were clearly identified.

Crystalline collimators can potentially considerably improve the cleaning performance of the presently used collimator systems using amorphous collimators. A crystal-based collimation scheme which relies on the channeling particle deflection in bent crystals has been proposed and extensively studied both theoretically and experimentally. However, since the efficiency of particle capture into the channeling regime does not exceed ninety percent, this collimation scheme partly suffers from the same leakage problems as the schemes using amorphous collimators. To improve further the cleaning efficiency of the crystal-based collimation system to meet the requirements of the FCC, we suggest here a double crystal-based collimation scheme, to which the second crystal is introduced to enhance the deflection of the particles escaping the capture to the channeling regime in its first crystal. The application of the effect of multiple volume reflection in one bent crystal and of the same in a sequence of crystals is simulated and compared for different crystal numbers and materials at the energy of 50 TeV. To enhance also the efficiency of use of the first crystal of the suggested double crystal-based scheme, we propose: the method of increase of the probability of particle capture into the channeling regime at the first crystal passage by means of fabrication of a crystal cut and the method of the amplification of nonchanneled particle deflection through the multiple volume reflection in one bent crystal, accompanying the particle channeling by a skew plane. We simulate both of these methods for the 50 TeV FCC energy.

Under coherent interactions, particles undergo correlated collisions with the crystal lattice and their motion result in confinement in the fields of atomic planes, i.e. particle channeling. Other than coherently interacting with the lattice, particles also suffer incoherent interactions with individual nuclei and may leave their bounded motion, i.e., they de-channel. The latter is the main limiting factor for applications of coherent interactions in crystal-assisted particle steering. We experimentally investigated the nature of de-channeling of 120 GeV/c $e^{-}$ and $e^{+}$ in a bent silicon crystal at H4-SPS external line at CERN. We found that while channeling efficiency differs significantly for $e^{-}$ ( $2\pm 2$ $\%$ ) and $e^{+}$ ( $54\pm 2$ $\%$ ), their nuclear de-channeling length is comparable, $(0.6\pm 0.1)$ mm for $e^{-}$ and $(0.7\pm 0.3)$ mm for $e^{+}$ . The experimental proof of the equality of the nuclear de-channeling length for positrons and electrons is interpreted in terms of similar dynamics undergone by the channeled particles in the field of nuclei irrespective of their charge. Under coherent interactions, particles undergo correlated collisions with the crystal lattice and their motion result in confinement in the fields of atomic planes, i.e. particle channeling. Other than coherently interacting with the lattice, particles also suffer incoherent interactions with individual nuclei and may leave their bounded motion, i.e., they de-channel. This latter is the main limiting factor for applications of coherent interactions in crystal-assisted particle steering. We experimentally investigated the nature of dechanneling of 120 GeV/c $e^{-}$ and $e^{+}$ in a bent silicon crystal at H4-SPS external line at CERN. We found out that while channeling efficiency differs significantly for $e^{-}$ ($2\pm2$ $\%$) and $e^{+}$ ($54\pm2$ $\%$), their nuclear dechanneling length is comparable, $(0.6\pm0.1)$ mm for $e^{-}$ and $(0.7\pm0.3)$ mm for $e^{+}$. The experimental proof of the equality of the nuclear dechanneling length for positrons and electrons is interpreted in terms of similar dynamics undergone by the channeled particles in the field of nuclei no matter of their charge.

The possibility of high-energy positively-charged particle beam splitting by means of a short bent axially oriented silicon crystal was recently reported in an experiment carried out at CERN SPS H8 extracted line with a 400 GeV/c proton beam. Here, we investigate more deeply such a possibility focusing our attention on the efficiency of beam splitting and its modulation for different crystal-to-beam orientations. New experimental results confirm the possibility of modulating the 400 GeV/c proton beam intensity in different planar channels by adjusting the orientation of the crystal. Furthermore, an analysis of the beam splitting efficiency vs. the curvature of the crystal was carried out through simulation, highlighting that there exists a bending radius for which the efficiency is maximal.

The dependence of thermal conductivity of polymer composites based on Viksint PK-68 on the dispersion composition of such fillers as powders of silicon carbide and microdiamonds has been studied. It has been shown that the thermal conductivity of polymeric compositions depends on the gradient of fractions in the powders of fillers.