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1.  Telemetering methods, devices and their application in vertebrology
S.N. Kulish, O.Y. Kagan
radiotelemetring research, transmitter, radio channel, implant devices, spine, impellent segments
Vestnik KhNU 712 Pages. 33-36

In the given job the review and the analysis of existing telemetering methods of research and diagnostics of various diseases in medicine is resulted. It is offered to use means of radiotelemetering research for registration of mechanical parameters arising on contact and lateral surfaces of impellent segments of a backbone. The block diagram of multichannel telemetering system is resulted and the basic requirements shown to this system are described

2.  Longitudinal slot radiators cut in circular waveguide
E.Y. Belogurov, V.A. Katrich, V.A. Lyaschenko
circular waveguide, axial slot, electromagnetic waves, radiation, slot antennas
Vestnik KhNU 712 Pages. 37-41

Using method of magnetomotive forces investigations of behaviors of longitudinal slots that were cut in wall of the circular waveguide were carried out. Expressions of internal self-admittance and transfer conductance were de- rived. The possibility of creation of a tapered illumination that forms radiation pattern with low side lobes on long slot cut in circular waveguide was shown

3.  The finite difference scheme in time domain (FDTD) and analytical solution to Klein-Gordon equation
Yu Zheng, B. A. Kochetov, A.Yu Butrym
Klein-Gordon equation, FDTD, finite difference equation, Laguerre impulse
Vestnik KhNU 712 Pages. 91-94

A finite difference algorithm for solving inhomogeneous Kleine-Gordon equation in Time Domain with arbitrary waveform pointwise source is considered in the paper. The numerical results were compared with analytical so-lution that was obtained using Laplace transformation in a convolution operator form. The results confirm validity of both the obtained numerical algorithm and the analytical solution

4.  Stimulation of the size evolution of the gas includes in a liquid by electromagnetic waves
B.G. Yemets
electromagnetic waves, air bubbles in liquid, temperature field, convection
Vestnik KhNU 712 Pages. 127-131

Based on the model considerations it was shown that irradiation of liquids containing gas inclusions with electromagnetic fields of "slowly-convective" intensity is conducive to the changes in the inclusion size

5.  On the field fluctuations in the diffraction pattern of focusing systems
Ya.S. Shifrin
fluctuations, amplitude, phase, focal plane
Vestnik KhNU 756 Pages. 5-10

There are considered the amplitude and phase fluctuations of the field in the focal plane of the focusing system, when a was with the field fluctuations falls on it. Plots illustrating the distribution of dispersions of amplitude and phase of the field along coordinate axes in the focal plane are given. There are analyzed a general case when both the amplitude and phase fluctuation of the field are present in the incident wave, as well as cases when it is possible to be restricted by regard of only either the phase or the amplitude fluctuations of the field in the antenna aperture. It is shown that in the latter cases, for determination of dispersions of the phase and amplitude fluctuation of die field in the focal plane, it is possible to use the same pictures with tk corresponding replacement of curves and conclusions accompanying them.

6.  On the directive gain of the self-focusing antenna
Ya.S. Shifrin
directive gain, self-focusing antenna, inhomogeneities, structure function
Vestnik KhNU 756 Pages. 11-17

The influence of the atmospheric inhomogeneities on the directive gain of the self-focusing antenna array (SFAA) at description of the atmosphere by the theory of the local-isotropic turbulence is considered. There are analyzed two cases when a size of the SFAA subaperture is respectively more or less than the turbulence scale of the medium. It is shown mat the results of the meat directive gain estimation for the two cases are well conformed qualitatively with the analogous estimates obtained at the atmosphere description wife the help of the Gaussian correlation function of its refractivity index

7.  Radioacoustic wind sounding of the atmosphere bo un dat y layer: history of the development and perspectives
Y. N. Ulyanov, V. I. Vetrov, N. G. Maksimova
radioacoustic, wind, sounding, atmosphere, boundary layer, profile, adaptation
Vestnik KhNU 756 Pages. 27-32

The article is devoted to the potentialities of the method of radioacoustic sounding when monitoring the vertical structure of the wind in the atmosphere boundary layer (ABL). A review of methods for radioacoustic measurements of the horizontal wind velocity and direction is based on the developments of the authors and their experience in this field as well as on the world experience. It is emphasized that the radioacoustic method for sounding the wind in ABL is perspective, since for the RAS equipment, there are not characteristic neither high levels of the electromagnetic pollution of the environment like for radiolocation wind profilers - radars nor loss of the serviceability at ligh levels of the ambient acoustic noise like for acoustic wind profilers - sodars.

8.  One-dipole inverse problem of magnetostatics for reconstruction of heart-torso electric activity from magnetocardiography measurements
Bagatskaya O., Butrym A., Durneva Yu., Shulga S.
Do not determinated
Vestnik KhNU 756 Pages. 47-50

Do not determinated

A.G. Tyzhnenko, Y.V. Ryeznik
testing, reference solution, moment's method, 2-D screens
Vestnik KhNU 756 Pages. 65-70

The scattering amplitude error estimation problem for practically used MoM solutions in L2 function space for scattering from 2-D screens is addressed. To this end, a rigorous Galerkin solution in L2 to logarithmically singular and hypersingular EFIE is used as a reference solution for scattering amplitude error estimation by benchmarking. This one requires substantially lower computational efforts than using of the same MoM algorithm but with very high mesh density as a reference solution. To many, the approach helps to avoid unpredictable errors due to the ill-conditioning connected with high mesh density for any MoM solution to the EFIE in L2. Using the approach, the asymptotic decay rate of scattering amplitude error is investigated for some MoM algorithms widely used in practice

10.  The Gaussian beam scattering on the bounded sequence of alternate grates of dielectric bars
V.B. Kazanskiy, V.R. Tuz, D.V. Yudintsev
Gaussian beam, thick grate of dielectric bars, anisotropic layer, periodic structure
Vestnik KhNU 756 Pages. 83-86

The Gaussian beam scattering on bounded periodical sequence of thick grates of dielectric bars are investigated. Identification of discrete structure with appropriate thickness homogeneous anisotropic layer was carried out for define sequence basic element transmission matrix. The sequence scattering coefficients were written down via Mougin polynomials. The effects of form distortion, beam splitting into several beams, side shift of beam axe were shown. Their correlation with scattering coefficients phase and module angle dependence of separate grates was established.

11.  On the primary mechanism for microwave therapeutic effects arising during gamma ray pathology
B. G. Yemets
electromagnetic microwaves, gamma rays, air bubbles, biologically active points
Vestnik KhNU 756 Pages. 139-143

The biologically active points (BAP) show an increase in size due to an increase in size of air bubbles at near-membrane water layer in the biologically active point cells. The increase in the air bubble size is produced by sweeping the microwave frequency.

Nesterenko, E.Y. Belogurov, V.A. Katrich, V.I Kijko
impedance vibrator, biconical vibrator, distributed surface impedance, rectangular waveguide, the method of induced electromotive forces
Vestnik KhNU 806 Pages. 14-17

The problem of the fundamental wave scattering by the thin variable radius impedance vibrator arbitrary situated in a rectangular waveguide was solved. Calculations were carried out and energetic characteristics of such structures were plotted

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13.  Resonance phenomena occurring as a thin refractive cylinder diffracts the hertzian wave
Yu. I. Grebenyuk, N. G. Kokodiy, Khe Shi
diffraction, thin cylinder, refractive index, scattering, absorption, weakening, resonance
Vestnik KhNU 806 Pages. 33-39

On the basis of solutions to the wave equation, the efficiency of dispersing, absorbing, and weakening the electromagnetic field that a thin cylinder with a large refractive index diffracts has been estimated. The transverse and longitudinal distribution of the electromagnetic field inside and outside of the cylinder has been calculated. The resonance is found to increase the intensity of both the electromagnetic wave field inside the cylinder and the scattered wave outside. Inside the cylinder at resonance, a wave propagating along its surface arises, and under some conditions, a wave propagating through the cylinder is also generated. As the refractive index is increased, the wave tracks the cylinder surface more closely, and its intensity is progressively enhanced.

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14.  Identification and localization of radar impulses buried in noise
A. G. Tyzhnenko, Y. V. Ryeznik
radar, pulse, identification, localization, low SNR
Vestnik KhNU 806 Pages. 70-74

Statistical method identification and localization of radar impulses buried in noise is addressed. To this end, the correlation coefficient between carrier samples measured in the extremal points and analogous set of points of received signal is proposed to implement. Such measurements for receiving signal need to be done at least by one tenth of the half period of the carrier. Because of very simple algorithm proposed, such measurements do not lead to heavy computational burden. To decrease identification and localization errors for given signal to noise ratio (SNR) one needs to increase the number of measurements points, and hence, the pulse width. To prevent this issue, one can increase the carrier frequency. In general, the method accuracy increases with the carrier frequency. The method proposed permits theoretically to identify with fidelity impulses buried in noise for SNR lower than -30 dB.

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15.  Application of the digital holographic interference microscope for investigation of thin films
D.N. Tishko, T.V. Tishko, V.P.Titar, Yu. A. Zadneprovskiy, A.S. Kuprin, I.A.Zgoda
digital holographic interference microscope, three-dimensional images, vacuum-arc method, thin AlN films
Vestnik KhNU 806 Pages. 99-102

For the first time the digital holographic interference microscope (DHIM) was used for investigation of thin films on transparent substrates. Three-dimensional images of AlN of thin films, deposited on acryl substrates by the vacuum-arc method have been obtained, their thicknesses have been measured. It has been shown that the DHIM can be successfully used for film surface quality checking, thickness and film damages parameters measurement.

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16.  Increase of free volume 0f the aip abundant in the water by the millimeter waves of low intensity
B. G. Yemets
electromagnetic waves, air bubbles, field of temperature, convection
Vestnik KhNU 806 Pages. 103-106

Using an NMR technique the volume growth of the free ("bubble") air contained in water caused by low-intense electromagnetic waves is obtained. This change is caused by rectified diffusion of the dissolved air mass into bubbles. The increase in the free air may occure only under those conditions when there is no convection in the liquid, i. e. in the case of irradiating by means of low-intense waves.

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17.  Subterahertz diffraction radiation on the BWO frequency harmonics in the parametrical two-regimes electron device
E.N.Odarenko, A.A.Shmatko, P.V. Yudintcev
diffraction radiation, Smith-Purcell effect, subterahertz waves, beam-wave interaction, nonlinear processes
Vestnik KhNU 834 Pages. 13-17

Diffraction radiation nonlinear theory that takes into account two-regimes interaction self-consistent regimes of the BWO and GDI on the BWO frequency harmonics is developed. The existence of the BWO generation regime on the first harmonic and parametric type diffraction radiation amplification regime on the BWO frequency harmonics is shown on the base of the self-consistent equations set numerical solution. Ranges of the task parameters values that correspond to two-regimes interaction are defined

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18.  Radiation of short pulses from the open end of waveguide
O.M. Dumin, O.O. Dumina, V.O. Katrich, Zheng Yu
transient field, modal basis method, evolutionary equations, impulse field irradiation
Vestnik KhNU 834 Pages. 63-67

The problem of transient electromagnetic field radiation from the open end of waveguide is solved in time domain by the analytical and direct numeral methods. The problem of impulse signal propagation in regular waveguide is converted to the finding of transient wave propagation operator by modal basis method. The application of the operator for the obtaining of time form of signal both for the time change in positive and in the negative direction permits to seek an arbitrary time dependence of field amplitude in any point of waveguide taking into account distortions due to wave dispersion. The correction of diffraction distortions of time form of wave and forming the short probe impulse on the waveguide aperture by the excitation of waveguide in the given cross-section by field with the previously calculated time dependence are considered . Numerical simulation of short impulse irradiation of layered medium with losses is carried out

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19.  Pulse water insonification for laboratory research of electromagnetic wave propagation and dispersion in randomly inhomogeneous media in order to meet the conditions close to working ones
V.B. Yuferov, A.N. Ponomarev, E.V. Mufel, A.N. Ozerov, I.V. Buravilov, V.N. Ishenko
electromagnetic wave propagation, inhomogeneous medium, air bubbles in liquid, acoustic pulse pneumatic radiator
Vestnik KhNU 834 Pages. 114-119

The efficiency of pulse water insonification by pneumatic radiator is shown. Such radiator enables the formation above the water surface of hydrometcors and aerosols with a desired concentration. It is necessary for laboratory research of fluctuation phenomena of the electromagnetic wave propagation in randomly inhomogeneous media. The use of pneumatic radiator makes possible lo remove salt from the solution. This enables a certain degree of control over liquid permittivity

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20.  Single cone with longitudinal slots excitation by an impulse point source
A.V. Artyukh, y.A. Doroshenko, Y.D. Shimuk
impulse source, cone, longitudinal slots, analytical solution, numerical solution
Vestnik KhNU 853 Pages. 51-56

In this work the excitation of a semi-infinite perfectly conducting cone with periodic longitudinal slots by an impulse radial source problem is investigated. The solution of the well-posed initial-boundary problem is found using an analytically numerical method based upon Green function and Meler-Fock integral transforms applying. It is shown that the original electrodynamic problem is equivalent to the one of the Fredholm linear algebraic equations system of the second kind solving. Analytical view of the solution is derived and the graphs illustrating the field dependence on the aperture angle and angle slot width are presented

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21.  HF ionosonde signal focusing by traveling ionospheric disturbances
Yu. B. Milovanov, V. F. Pushin, O. F. Tyrnov
traveling ionospheric disturbances, signal amplitude variations, Doppler frequency shift, focusing factor, computer simulation
Vestnik KhNU 853 Pages. 88-94

HF signal focusing due to linear and nonlinear wave disturbances occurring during monostatic ionospheric sounding is discussed. A technique is developed for estimating signal amplitude variation due to focusing based on beating amplitude measurements during significant Doppler frequency shift events. The intercomparison of measured and modeled variations in beating amplitudes, the focusing index, and Doppler frequency shift show a qualitative agreement. The simultaneous analysis of variations in the beating amplitude and the Doppler frequency shift makes the interpretation of measurements more definite, e.g., it permits the isolation of large scale disturbances traveling at approximately 1 km/s

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22.  Random inhomogeneous liquid medium as a continuous laser of low-intensity modulator for excitating sound in the medium
B. G. Yemets
laser, random inhomogeneous liquid medium, interference, temperature field, optical acoustical phenomenon, sound, excitation, modulation
Vestnik KhNU 853 Pages. 95-100

When a medium is irradiated by laser pulses, sound waves are excited in this medium, i.e., the well-known optical acoustical phenomenon occurs. To excite sound oscillations, the specific laser beam modulator is shown to be unnecessary. The role of the modulator can play the liquid itself, which is a random inhomogeneous medium. The real liquid contains suspended solids and gas bubbles of small dimensions (dust particles and the like) that move irregularly in space (fluctuations). As a result, the electromagnetic wave interference taking place in the liquid undergoes random changes. Consequently, the temperature field changes, and hence variations in the local pressure occurs (thermo-optical mechanism for exciting sound). The excitation of sound due to the laser irradiation of low intensity is observed in an increase in the gas bubbles dimensions in the liquid

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23.  Polarization and energy characteristics X-slots in the waveguide with the complex load and the dielectric inserts
Blinova N.K., Yatsuk N.N., Selyutin A.V.
-slots , ellipse coefficient, VSWR level , circular polarization.
Vestnik KhNU 966 Pages. 77-81

The -slots in a rectangular waveguide with the end complex loading and dielectric inhomogeneity at the waveguide input are considered. Calculation and experimental results of power and polarization descriptions are carried out for such systems. The possibilities of polarization and power characteristics of -slot control are investigated. The variation of dielectric inhomogeneity and complex end loading parametors allows to obtain the circular polarization, high radiation coefficient and low VSWR level

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24.  New statistical methods of recognition and classification for automatic interpretation of remote observations
Koltunov Y.A., Dumin O.M., Katrich V.A., Naumov R.R.
methods of recognition and classification, blenderized models of the probabilistic distributing, teaching selection
Vestnik KhNU 966 Pages. 37-49

Mathematical models, computational algorithms, and also prospects of development and application of three new methods of recognition and classification (RC), namely, construction of distinctive characteristics of objects; classification on the basis of probabilistic teaching selection with optimization of method RAC; account of dynamics of features of recognized objects are presented in the article. Recognition and classification is an area of modern science that have a boundless list of applications in all spheres of human activity. From the list of applications the only one is selected in the present work, but the most actual one, that is the remote sensing of ground surface in radiofrequency band with the purpose of study and maintainance of natural resources of Earth.

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Development - V.N. Karazin Kharkov National university