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The authors have obtained the analytical relations for the plane electromagnetic wave reflection coefficient at the borehole-borehole environment interface. The numerical modeling of directivity diagrams is carried out on the scale of the gain factor of a dipole antenna arranged in the borehole environment in an oil reservoir. The modeling takes into account the influence exerted by the properties of the borehole fill material on the electromagnetic field of the antenna in the radio-frequency range.

The focused ion beam treatment of substrates with transparent electrodes coated with rubbed polymer layers is a key step in creating liquid crystal metasurfaces. This treatment provides local control over the liquid crystal alignment near the substrate surface. The structure, composition, and optical properties of the FIB-treated substrate surface were studied by the scanning electron microscopy, transmission electron microscopy (TEM), atomic force microscopy, optical microscopy, and Auger electron spectroscopy. The effects of rubbing and ion-beam irradiation are analyzed to elucidate the microscopic features and the reasons for changes in aligning properties.

Propagation of a plane electromagnetic wave of the microwave range is simulated to calculate the coefficient of its reflection from a homogeneous layer. A particular case of a multilayer geomediumis considered: an oil-saturated formation enclosing a hydraulic fracture. When justifying the choice of the frequency range, the value of fracture surface irregularity was taken into account. The dependence of the reflection coefficient on frequency for an electrically less dense non-absorbing layer inside a denser non-absorbing substance (a void layer inside a rock) has been calculated.

The software and hardware tools for the instrumental estimation and control of the geomechanical state of engineering facilities are presented. A description of the proposed technique for measuring radial and longitudinal displacements of check borehole contour is given. A research methodology and interpretation of experimental data with analysis and monitoring of the stress-strain state of engineering facilities are proposed. The results of testing the developed software and hardware in the conditions of industrial enterprises are presented.

Various types of nanowires obtained by matrix synthesis --- homogeneous (from iron) and heterogeneous (layered) --- have been studied. A technique for obtaining arrays of layered nanowires with alternating thin layers of magnetic and non-magnetic metals (Co/Cu, Ni/Cu) has been developed and described. Microscopy methods (SEM and TEM with elemental analysis) have been used to study the topography of the resulting structures, the diameters of nanowires and the thicknesses of individual layers, and the features of interlayer interfaces. Methods of synthesis of nanowires with thin layers and clear boundaries are proposed --- dilution of the electrolyte, use of a reference electrode, control of the leaked charge. Layered nanowires have been studied by magnetometry methods and it has been shown that the magnetic properties of an array of layered nanowires (in particular, the direction of the axis of light magnetization in the Co/Cu-NP array) depend not only on the aspect ratio of the magnetic layer, but also on the ratio of the thickness of the magnetic metal layer to the thickness of a non-magnetic spacer (copper layer). The nuclear magnetic resonance (NMR) method was used to study two types of nanowires. The NMR method (on 59-Co nuclei) studied the layer structures of Co/Cu: it is shown that in nanowires with layers of smaller thickness (and, accordingly, with a large contribution of interfaces), a large proportion of Co atoms coordinated by Cu atoms is observed. The high proportion of atoms coordinated by copper suggests that an admixture of copper enters the cobalt layers. Homogeneous iron nanowires (NMR on 57-Fe nuclei) were compared with bulk iron samples. A shift of the line towards high frequencies (by 0.3 MHz) was detected, indicating an increase in the field by about 0.2 T. A significant broadening of the line and a decrease in the spin-lattice relaxation time may indicate a significant variation in the local magnetic field values. Keywords: nanowires, matrix synthesis, microscopy, elemental analysis, magnetic properties, NMR.

The authors discuss the problem connected with the assessment of hydraulic fracturing quality in oil-filled formations by means of location and sizing of hydrofractures. The proposed engineering solution is to design a down-the-hole measuring probe based on the ground penetrating radar method in the range of microwaves. The authors select the model and mode of an antenna assembly for the down-the-hole probe. The width of the the major maximum of the antenna assembly pattern is determined.

The spectral curve of the flux density of the radiation, which is reflected by the full moon towards the Earth’s ionosphere within a wavelength range of 200–1700 A, has been presented. This curve is obtained by the approximation of space experiment data available in the scientific literature on the lunar spectral albedo and solar spectrum. Estimates of maximum values of spectral densities of fluxes reflected by the full moon in the neighborhood of wavelengths of ionization of basic ionospheric particles (neutral atoms of H I, He I, N I, O I, and Ar I and ions of He II, N II, O II, Ar II, N III, O III, and Ar III, as well as molecules of H2, N2, and O2) are given.

An overview of methods for mapping disturbances in a rock mass is given on the example of determining hydraulic fracture systems in an oil-filled formation. Methods of passive and active microseismic monitoring, as well as electromagnetic examining of rock masses for the presence of inhomogeneities in it are considered. A promising option for the development of hydraulic fracture mapping systems is proposed - creation of downhole logging probes representing ground penetrating radars that implement the mode of electrical scanning of the rock mass under study. The calculation of downhole antenna array based on the Butler matrix is performed. The calculated parameters of a phased antenna array with a Butler matrix can be used to design a downhole logging probe for mapping hydraulic fractures, as well as for surveying engineering structures, for example, foundations of buildings.

Numerical modeling was performed for stress-strain state of the rock mass and lining of underground turbine hall of Rogun hydropower plant. The hall is located in a rock mass at great depths. Numerical modeling was conducted using the method of boundary integral equations based on the model of linearly elastic quasi-isotropic medium. The character and features of forming inelastic deformation zones near the contour of turbine hall cross-section are found. The regularities of distribution of rock mass and lining stress-strain state are determined as well.

The acoustic data measurement system and processing algorithm are developed to position a pneumatic impact machine in soil. The method is based on recording lag time of entry of acoustic signal generated on interaction between the pneumatic impact machine and soil in the receiver of multichannel measurement system relative to reference signal of the machine. The measurement system and the algorithm have been trialed in full-scale conditions.

The factors that influence geomechanical state of rock mass in Sheregesh Mine are determined. The authors discuss a variant of geotechnology with fan drilling. The drill-hole patterns and drilling-and-blasting parameters are presented. The revealed causes of low-quality fragmentation of rocks include the presence of closed and open fractures at different distances from drill-hole mouths, both in case of rings and fans, as well as the blocking of drill-holes with rocks.

The research is dedicated to the question of international studentsтacademic mobility automatization due to engineering and design of the special information system. This system should minimize the role of an expert at each stage of mobility support. Some features of such system are considered in the paper. В докладе рассматривается вопрос автоматизации международной студенческой академической мобильности за счёт разработки и внедрения информационной системы, минимизирующей участие эксперта в процессе сопровождения мобильности. Выдвинуты идеи относительно составных модулей такой системы.

A quantitative analysis is presented of the data on modification of the ionosphere by high-power radio emission from the SURA heating experiment run on October 2, 2007 (18:40 – 19:00 UT). The Sura facility was working in the mode of periodic heating at the radio frequency (RF) of 4.30 MHz. The modulation frequency was close to the frequency of natural Alfven oscillations of plasma in the local magnetic flux tube. The effects of modification were observed onboard the Russian Segment of the International Space Station (RS ISS). The observations have provided more than 1500 images of a bright local glow, which appeared within the field of view of the TV camera as the ISS was passing close to the location of the Sura facility. The brightness of aurora reached some hundreds of kiloRayleighs. The compact bright aurora appeared North-East of the heating facility and was moving East in the image plane. The analysis of helio-geophysical conditions did not reveal any significant anomalies during the experiment. A low power of the heating RF emission and high intensity of the observed aurora suggest that the local glow wasn't due directly to HF heating of ionosphere, but rather might be caused by the particle precipitation artificially stimulated by the heating effects, such as modification of the ionosphere over the SURA heating facility, which forms the base of the magnetic flux tube (and the standing wave node) whose natural Alfven oscillations have a period close to the modulation period of the heating HF emission. The Alfven mode of the magnetic tube could be intensified during the experiment by a short (less than 1 min) and weak (amplitude of about 2 nT) pulse in the planetary geomagnetic field that occurred at 18:47:30 UT.

Method of the atomic oxygen concentration distribution in upper Earth atmosphere on 90-130 km altitude has been developed. The method is based on analysis of the night limb UV (λλ 250 - 330 nm) glow images taken from International Space Station. Intensity of this radiation is directly related to the atomic oxygen content.