IKBFU's Vestnik

Physics, mathematics, and technology

Experimental and technical physics

Investigation of changes in the paramets of thin films structures during ion implantation

Abstract

In this paper were investigated the change of parameters of structures of thin film during ion implantation. Thickness of thin films before and after ion implantation were investigated by X-ray reflectivity. Also, crystal structure, average crystallite size and lattice constant were investigated by X-ray diffraction. The possibility of using ion implantation technique as method of changing grains size in structures was demonstrated.

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Investigation of dependence of temperature coefficient of linear expansion on integrated intensity of the main peak of pyroceramics substrate

Abstract

This paper presents the results of studies of the parameters of optical components of a glassceramic material CO-115 by X-ray diffractometry. The possibility of technological precision quality control glassceramic parts using X-ray diffraction methods. The direct dependence of the temperature coefficient of linear expansion of the integrated intensity of the X-ray diffraction peak at the glassceramic.

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Bipolar resistive switching in memristive thin films based on Si-Ag

Abstract

In this work were investigated surface and electrophysical properties of multilayer thin film structures based on Si/Ag, grown by Ion-Plasma Deposition method. There were developed and optimized method of structure formation, which consist of silver clusters in silicon medium. Current-voltage curves were observed on prepared structures and demonstrate resistive switching behavior.

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Creation of the effective cathode jack for the micro-SPD

Abstract

This paper presents the scope of challenges which are faced in development and manufacturing of the cathode-compensator dedicated for micro-SPTs, and possible ways of how to overcome them. As compared to standard models, such a cathode shall be smaller in dimensions, shall have a lover propellant flow rate, as well as lover heater power and power consumption when self-operated; and it shall be able to operate in the current range of 0.3…1A or lower.

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Thermal calculation of the anode of the stationary plasma engine

Abstract

The paper includes the thermal calculation of the anode gas distributor in Stationary Plasma Thruster (SPT) discharge system made with SolidWorks Software, that allows to determine with sufficient accuracy the model’s sensibility vs. variation of the different parameters. The calculation can define the minimum area of fusion penetration between anode’s components during braising in order to obtain the thermal picture of the item design.

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Radiophysics and radiotechnique

Numerical simulation of the ionospheric effects of geomagnetic storm on 2—3 may 2010 at the HF radio wave propagation in the low-latitude region

Abstract

For the first time we used a global three-dimensional theoretical model of the thermosphere-ionosphere system for the description of inhomogeneous anisotropic medium in the simulation of radio wave propagation. It is shown that the results obtained with joint using GSM TIP model and radio wave propagation model adequately describe HF radio paths in the Earth's ionosphere in quiet conditions and at the recovery phase of geomagnetic storm.

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The features of electron density behavior in the ionosphere-plasmasphere system above equatorial station Jicamarca in the end of September 2011

Abstract

We present the analysis of the ionosonde and incoherent scatter radar (ISR) data of ionospheric parameters over Jicamarca (Peru) in quiet conditions and during geomagnetic storms on 22—29 September 2011. According to ISR data the estimation of the ionospheric contribution to the Total Electron Content (TEC) was carried out. These observation data are compared with GSM TIP model calculation results. The features of the electron density Ne behavior in the equatorial ionosphere and, in particular, F3 layer behavior, were identified. The agreement of the model calculation results and observation data analysis was obtained in quiet conditions and during geomagnetic storms.

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Application the theory of an optimum detection for a spatial resolution of signals

Abstract

The article deals with application of the theory of optimum detection to the azimuth resolution of two sound sources. This paper compares the solutions based on maximum likelihood method with the classical approach (Rayleigh's approach). Furthermore, the computer model and the testbench (experimental apparatus) have been created for an extensive analysis of the obtained solution. Our experimental and model results demonstrate a significant advantage of the solution obtained by using the theory of optimum detection. The purpose of this study is present the possibilities and advantages of the maximum likelihood method.

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Way of shortening the inclusion of antennas of the transducer of the impedance shoulder vibrator

Abstract

A method is proposed shortening of vibrator antenna. Capacitive reactance is compensated offset by the inclusion of the extension of the inductance coil in the shoulders vibrator. This interpretation of the short tape antenna gives the opportunity to increase the power of the radiation virtually reducing the efficiency of the antenna system, in a result of losses on the inductive element.

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The properties of a tunable frequency oscillator with the partial inclusion of the transistor in the circuit

Abstract

The properties of a tunable frequency oscillator with a circuit between the collector and the base of the partial inclusion of the transistor in the circuit were studied using a method based on the presentation of bipolar transistor equivalent active two port circuit with negative conductivity.

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Building transmitter circuit for the study of parameters of system of secondary emitters

Abstract

Suggest a method for constructing a system of magnetic coils, of the workspace in which excited облучающее sample magnetic field used to study the parameters of the system of secondary emitters. Theoretically formulated and practically implemented model of the feed, providing the creation of a uniform magnetic field on the stage. The measurements of the distribution of magnetic field in облучателе to judge the appropriateness of the use of the system in experimental techniques.

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Evaluation of error probability in determining of reception time of RZS in the presence of white noise

Abstract

The error origins in determining of reception time of radio probing signal are considered in this article. Also the method of error probability calculation was offered in this work. The analysis of maximum probability of such error was carried out for phase-shift keyed signal on the base of Barker’s code and radio signal without intrapulse modulation.

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Applying artificial neural networks for prediction of radiowave propagation features

Abstract

Possibility of artificial neural networks application in purpose of propagation loss prediction and defining of statistics parameters: standard deviation of signal level, probability of area coverage and probability of exceeding of threshold is examined. Neural networks were created for prediction of these parameters. Performed accuracy is estimated.

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Dipolarization of the earth magnetic field and charge particles precipitation from the magnetic flux tube

Abstract

During the expansion phase of the substorm in the nightside magnetosphere enhancement of the magnetic field and decrease the plasma pressure is observed simultaneously. Enhancement of the magnetic field is recorded at first in the tail of the magnetosphere, and then at more closer distances from the Earth. This process takes a few minutes and covers the region in the magnetosphere of 10 Earth radii. One of possible explanations of this phenomenon is associated with cooling magnetic flux tubes caused by the precipitation of the energetic particles in the ionosphere. We have made evaluation of the effectiveness of this mechanism.

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Informatics and mathematical geophysics

New possibilities of passive microseismic monitoring applying for structural-tectonic features detection of oil and gas fields

Abstract

There is described multifunctional surface small aperture aerial technology of microseismic monitoring. This technology is used for monitoring of hydraulic fractioning, fluid injection and for other well interventions. In addition it allows to describe crosshole block discontinues structures of collector in the mode of long passive microseismic monitoring. First in the world, there is presented crosshole block discontinues model of hydrocarbon field obtained based on microseismic monitoring.

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Verification modified model bio productivity EPIC at regional level

Abstract

The results of applying bio productivity model EPIC wheat yields by administrative areas using data network of weather stations Roshydromet. Validation of model was carried out sub-satellite measurements on the basis of test fields with use stationary meteorological station, spectrophotometer and LAI measuring instrument. Modeling accuracy compared to the yield of individual fields, areas and regions.

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Techniques for identification and visualization of faults and technology-related fractured zones using micro-seismic monitoring data processing

Abstract

The article describes the approach to development of software for processing of micro-seismic monitoring data represented by point cloud. The first version of the development «Software for geophysical data visualization and faults detection» allows for parametric visualization of micro-seismic activity points and contextual information, piecewise linear fractures and faults recognition actualizing them in the form of flat landfills in 3D space. Approaches to faults and other rock objects recognition algorithms design are proposed.

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Semi-geodetic transformation of temporary images

Abstract

Often while seismic data processing one gets time dependent images (time cuts, time migration), in which time plays the role of the «depth» variable. If in some approximation the wave propagation velocity is known, these images can be transformed into the true ones. In this article for this purpose it is proposed to use semi-geodesic transform associated with the normal to the boundary rays. The results of simulations are presented.

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Mathematics

Numerical modeling of wave processes in 3D fractured media

Abstract

Seismic response from the cluster of vertical oriented cracks is simulated using grid-characteristic method on parallelepiped structured meshes. Synthetic seismograms and wave fields are calculated. The structure of the response including dependency on type of saturator (gas, fluid) is analyzed. Numerical experiments showed the effect of high-frequency daisy-chain wave’s generation from 3D periodic structures.

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