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Rybin O.,Kharkiv State University of Food Technology and Trade | Rybin O.,Kharkov National Academy of Municipal economics
International Journal of Applied Electromagnetics and Mechanics | Year: 2012

In the paper, the possibility of achieving negative permeability for two-component metamaterials is analytically proven. The metamaterial media are presented as an infinite host dielectric material (air) with periodically embedded ferric cylindrical and spherical inclusions saturated with a biasing external magnetic field. The appropriate frequency-dependent inequalities are obtained in the frequency range where permeability becomes negative. The cases when electromagnetic wave propagates parallel and transverse to the direction of biasing magnetic field are studied. © 2012 - IOS Press and the authors. All rights reserved.


Shepilko E.V.,Kharkov National Academy of Municipal economics
Radiophysics and Quantum Electronics | Year: 2010

We formulate and solve the problem of scattering of a plane electromagnetic wave by an infinite, perfectly conducting wedge with a truncated, perfectly conducting circular cylinder which is coated coaxially with a magnetodielectric layer and located along the wedge edge. The rigorous solution is obtained and reduced to a system of linear algebraic equations of the second kind for unknown coefficients of Fourier expansions of the scattered field. The results of calculating the scattered field in the far zone with a specified accuracy are presented for the case of an H-polarized wave. It is shown that for certain values of the electric radius of the cylinder, the backscattering cross section of such a structure has pronounced maxima. © 2010 Springer Science+Business Media, Inc.


Shepilko Y.V.,Kharkov National Academy of Municipal economics
Proceedings of International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory, DIPED | Year: 2012

Scattering of electromagnetic wave is considered for a composite cylindrical structure consisting of a dielectric covered slotted cylinder co-axially coupled with a metal cylinder sector. The boundary-value method is employed using completeness property of the angular functions in the respective intervals. Problem is reduced to solution of system of algebraic equations of second kind for the unknown coefficients of Fourier expansion of scattered field. Analytical solution is obtained for certain value of cylinder slot-width. Scattered far-field and back radar cross section (BRCS) of the structure are formulated. © 2012 Pidstryhach Institute of Applied Problem.


Shumakov F.T.,Kharkov National Academy of Municipal economics | Azimov O.T.,Scientific Center for Aerospace Research of the Earth
GeoInformatics 2013 - 12th International Conference on Geoinformatics: Theoretical and Applied Aspects | Year: 2013

Development of GIS and remote sensing devices has led to the empowerment of global problems of water quality monitoring in inland waters. The report provided a rationale for assessing the quality of water in reservoirs with integral and simple methods of water content in chlorophyll-a and water clarity by Secchi disk. Also describes the features of GIS technology using data from satellite images to determine the transparency of the water, the water content of chlorophyll-a, and for the trophic classification of lakes and reservoirs. In this paper, we describe how to obtain relations between the ground-based measurements of water quality and the optical characteristics of surface water in satellite imagery. Based on contact measurements and satellite images Landsat-5, Landsat-7 and Terra/Aqua-MODIS derived multiple regression equation relating the brightness of the water bodies in the space images c chlorophyll-a and water clarity by Secchi disk. The possibilities of this information for real-time monitoring of water quality in the reservoirs. The report also examined the use of satellite images to study the spatial and temporal characteristics of the processes of "flowering" of water and the distribution loops wastewater and sewage in water bodies to assess their impact on water quality. It is shown that for the study of point and diffuse sources of pollution and eutrophication of water bodies perspective to use space information (Google, Nokia, Bing Maps, Virtual Earth, SPOT-5, the substrate of the inventory).


Besougly A.V.,Kharkov National Academy of Municipal economics | Petchenko O.M.,Kharkov National Academy of Municipal economics
Telecommunications and Radio Engineering (English translation of Elektrosvyaz and Radiotekhnika) | Year: 2015

The quantum mechanics model of the electrons diffraction on the one-dimensional grating of the infinitely thin strips is proposed. Supposing that photons fighting through the slits interact with electrons of a solid, it is demonstrated that the diffraction pattern is determinated by the spectrum of momentums of electrons. The expression determining diffraction angles of scattered electrons coinciding in the case of small diffraction angles and grate of slip angles with known equation of diffraction grating is obtain. ©2015 by Begell House, Inc.


At quality assurance of composite and multilayered building materials in products the ultrasonic pulse method is widely used. Application of this method is caused by comparative simplicity of process of measurement, in particular at quality assurance of materials with known physic-mechanical characteristics. Thus, the most widespread technique of quality assurance is measurement of speed of distribution of a ultrasonic signal in an investigated material with the subsequent definition, for example, its durability. It is made, basically, on preliminary constructed correlation dependence speed of elastic waves - durability of a materials The significant error of measurement can appeal" at quality assurance of materials with the greater factor of attenuation of ultrasonic fluctuations. Such problem is present and at quality assurance of building materials at maintained constructions. The decision of a problem due to use of modeling of the form of an information signal is offered.


Petchenko G.A.,Kharkov National Academy of Municipal economics | Petchenko A.M.,Kharkov National Academy of Municipal economics
Functional Materials | Year: 2010

The frequency spectra of dislocation losses of ultrasound in LiF single crystals irradiated with 0 - 400 roentgen doses and preliminarily strained at ε = 0.3 % are investigated at room temperature in 22.5 - 232 MHz frequency range. It is found that the rise of X-ray irradiation doses is accompanied with clearly observed effect of dislocation resonance quenching which manifests itself in monotonous shift of the dislocation resonance maximum towards higher frequencies and lower amplitudes. The dependences of the coefficient of dynamic viscosity B and the average effective length of the dislocation segment L on the irradiation time ranging from 0 to 60 min are established and analyzed. © 2010 - STC "Institute for Single Crystals".


Petchenko G.A.,Kharkov National Academy of Municipal economics
Functional Materials | Year: 2012

To study the nature of the mechanisms that limit the viscous motion of dislocations, the dampfed dislocation resonance in LiF crystals at room temperature in the range of radiation doses of 0-1000 R has been scrutinized by the impulse echo method in the frequency range 37.5-232.5 MHz. From the frequency curves, taken from crystals with different doses of radiation, the dependencies of the viscosity coefficient B and the average effective length of the dislocation segment L from the time of irradiation has been determined. On the basis of the carried out measurements, calculations and analysis it has been concluded that the dynamic damping of dislocations in the given object, and given experimental conditions is determined only by the phonon spectrum of the crystal. © 2012 - STC Institude for Single Crystals.


Shepilko Y.V.,Kharkov National Academy of Municipal economics
DIPED - 2011: 2011 16th International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory, Proceedings | Year: 2011

Scattering of electromagnetic wave is considered for a composite structure consisting of an infinite dihedral wedge that is co-axially coupled with a dielectric covered slotted cylinder. The boundary-value method is employed using completeness property of the angular functions in the respective intervals. Problem is reduced to solution of system of algebraic equations of the second kind for the unknown coefficients of Fourier expansion of the scattered field. Analytical solution is obtained for certain value of cylinder slot-width. Scattered far-field and back radar cross section (BRCS) of the structure are evaluated asymptotically. The scattered field characteristics are also analyzed numerically with controlled precision. BRCS and the normalized radiation patterns of scattered field of narrow wedge for certain values of cylinder slot-width and electrical diameter of the cylinder are given. © 2011 Inst for Applied Problems.


Orel E.S.,Kharkov National Academy of Municipal economics
Low Temperature Physics | Year: 2012

The magnetic ordering temperature ΘC of systems with double exchange is calculated using a model of interacting spin systems. This is compared with calculations based on the molecular field model and the spin-wave model. A maximum of the magnetic transition temperature ΘC is obtained for an electron concentration x = 0.35, which is in better agreement with experiment (x = 0.33) than molecular field and spin-wave model calculations of ΘC. © 2012 American Institute of Physics.

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