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.
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.
Serikov J.,Kharkov National Academy of Municipal economics
Proceedings of Forum Acusticum | Year: 2011
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
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.