1. The finite difference scheme in time domain (FDTD) and analytical solution to KleinGordon equation Yu Zheng, B. A. Kochetov, A.Yu Butrym KleinGordon equation, FDTD, finite difference equation, Laguerre impulse Vestnik KhNU ¹712 Pages. 9194
A finite difference algorithm for solving inhomogeneous KleineGordon equation in Time Domain with arbitrary waveform pointwise source is considered in the paper. The numerical results were compared with analytical solution 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
2. ELECTROMAGNETIC WAVE SCATTERING FROM ANISOTROPIC INCLUSION IN RECTANGULAR SHORTCIRCUIT WAVEGUIDE N.P. Zhuck, V.I. Fesenko, S.N. Shulga, O.V. Bagatskaya, He Shi scattering matrix, rectangular waveguide, anisotropic medium Vestnik KhNU ¹756 Pages. 3337
The problem of determination of the scattering matrix coefficients from anisotropic inclusion in one side shortcircuit waveguide was considered. Calculation of the scattering matrix coefficient S_{10} for the anisotropic slab in the end of the empty rectangular waveguide is presented
3. Way of transformation of the patterns of reception antennas A.A. Sorokin, A.F Sorokin, O.V. Sokolova, R.N. Zaluzhniy, N.N. Gorobets miñrowaves, antennas, pattern, Frenel zones Vestnik KhNU ¹806 Pages. 2932
the expedient of management by the shape of directional diagrams with the help of a fragmentation of Frenel zones is offered. Measuring the shape of a pattern diagram of the horn and spiral antennas are carried out. Peak allocations a builder of a field in shortrange, medial and longrange bands for different frequency range are received and analyzed. By results of experiments intensity, a corner, radius for longrange and shortrange bands is constructed 3D images.
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4. The influence of a dispersion and losses to the interaction of impulse signal with the model of the biological tissues O.N. Zheryobkina, O.V. Kazanskiy impulse signal, a biological tissue, time domain, flatlayer dielectric, dispersion Vestnik KhNU ¹806 Pages. 4043
In this paper the interaction of the impulse signal with biological tissues on an example of the flatlayer dielectric that models consecutive layers a skin, fat, muscle tissue is investigated. In this model, it is taken into account dispersion of the dielectric permeability and losses in a medium. The calculation program is received in result. It accounts the spacetime characteristics of the reflected and past signals for layers of the flatlayer dielectric with parameters of biological tissues. Influence of values of the dielectric permeability and angle of incidence on the characteristics of past and scattered signals also is considered.
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5. Spatial and temporal features of the midlatitude total electron content I. G. Zakharov total electron content, dualfrequency Doppler shift measurements, planetary waves Vestnik KhNU ¹806 Pages. 8286
Experimental study of the latitudinal and diurnal variations in the total electron content over Eastern Europe are present. The dualfrequency Doppler shift measurements from navigation satellites and incoherent scatter radar (ISR) data are used The ISR data were collected near Kharkiv city (49.6^{o}N, 36.6^{o}E), and the dualfrequency signals from navigation satellites in circular polar orbits at the altitude of about 1000 km were received at the Kharkiv V. Karazin National University Radiophysical Observatory (49.6^{o}N, 36.3^{o}E). The calculated total electron content maps span the 35^{o} – 65^{o}N geographic latitude range and the 24hour local time range. These maps and other data represent all known features of diurnal and latitudinal total electron content variations at middle and subauroral latitudes, and in particular, they represent the local latitudinal maximum at 50^{o}N geographic latitude in total electron content. The results obtained also indicate that tidal and planetaryscale waves act to noticeably modify the temporal and spatial variability of TEC, including that under quiet conditions.
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6. 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, threedimensional images, vacuumarc method, thin AlN films Vestnik KhNU ¹806 Pages. 99102
For the first time the digital holographic interference microscope (DHIM) was used for investigation of thin films on transparent substrates. Threedimensional images of AlN of thin films, deposited on acryl substrates by the vacuumarc 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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7. Dispersive characteristics of magnetoplasma waves in the rectangular wave guide with InSb O.A. Zamuraev, O.O. Puzanov, A.S. Tishchenko magnetoplasma wave, semiconductor plasma, dispersive characteristics, nitric temperature Vestnik KhNU ¹834 Pages. 37
Frequency dependence of characteristics of magnetoplasma waves in the rectangular wave guide, containing longitudinal and crosssection  magnetized the semiconductor at various sizes of an induction of a magnetic field is experimentally investigated. Areas of values of an induction in which the behavior of wave number and factor of attenuation has resonant character are determined. An existence of two superficial magnetoplasma waves which are distributed in opposite directions is experimentally confirmed in longitudinal  magnetized semiconductor plasma. Good concurrence of results of experiment and numerical calculations is shown
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8. Features of the calculation of Focktype integrals V.I. Vyunnik, A.A, Zvyagintsev Focktype integrals, numerical integration, error estimate Vestnik KhNU ¹834 Pages. 5262
Calculation of Focktype integrals, used at the solutions of the diffraction problems on convex bodies is considered. The method of calculation of this integrals is described, and the estimation of their convergence is given. Range of values of the complex parameter, describing a surface impedance, for which the given method is applicable is determined. The estimation of the error of calculation is carried out
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9. 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 ¹834 Pages. 6367
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 crosssection 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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10. Oscillation efficiency of TED diodes on the basis of nitrides E. D. Prokhorov, O. V. Botsula, A. N. Zabazhan AlN, GaN, InNdiodes, drift speed, oscillation efficiency Vestnik KhNU ¹853 Pages. 1521
Oscillation efficiency of intervalley transfer electrons diodes on the basis of nitrides (InN, GaN, AlN) is considered. Electric fields at peak oscillation efficiency are determined. The results have been compared to results for GaAs. The account of floatable potential in connections InGaN improves their power characteristics in comparison with power characteristics of these connections without taking into account floatable potential, maximal efficiency In_{0.8 }Ga _{0.2N and In0.5Ga0.5N diodes to compare to InN diodes on 30 % is higher (22 % to compare to 16,43 %) but at more high tensions of an electric field. The maximal oscillation efficiency is observed at higher electric fields than GaAs ( from 250 êV/sm for InN to 1000 kV/sm for AlN)}
11. Asymptotic method of the solution of diffraction problem on the convex impedance cylinder, excited by the string of the electric current V.I. Vyunnik, A.A, Zvyagintsev diffraction, asymptotic method, interpolation, convex impedance cilinder Vestnik KhNU ¹853 Pages. 6470
In the work considered the problem of diffraction electromagnetic waves on the convex impedance cylinder exited by string of the electric current, located near to its surface. The method asymptotic theories of the diffraction, offered by Fok is used. Are received asymptotic interpolation formulas for calculation radar cross section of the system string the current  cylinder, for a case of circular and elliptic impedance cylinders. The received formulas are suitable for calculations both in shadow and in lighted areas. It is shown, that these formulas can be distributed on a case of the any convex impedance cylinder with variable curvature
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12. The accumulation of gas in galactic objects Sorokin A.A., Sorokin A.F., Zaharova M., Sokolova O.V., Gorobets N.N. astrophysics, galactic objects, the accumulation of gas Vestnik KhNU ¹883 Pages. 37
The mechanism of the accumulation of gas in the galactic objects submerged in the largescale magnetic field is examined. As a consequence of the diamagnetism of the plasma subsystem of object, the stopper geometry of magnetic field with the radial electr
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13. The xecl laser with the adjustable shape and duration of generation pulse S.S. Anufrik, A.P. Volodenkov, K.F. Znosko LC contour, XeCl laser, excitation system, generation energy, pulse duration. Vestnik KhNU ¹983 Pages. 310
The generation parameters of LCcontour excitation system are studied for electrodischarge excimer XeCl laser using a Ne–Xe–HCl mixture. A computation model is developed for finding the generation parameters. It has allowed us to calculate current, voltage and generation power oscillograms for all parameters of the electrical excitation system. The program of XeCllaser modeling enables to calculate an electrons, atom and molecule concentrations, specific energy deposition in active medium also. By means of program Bolsig + calculation of rate coefficients of reactions with participation of electrons is executed. It is shown that generation of short radiation pulses (20 ns) and relatively long pulses (60 ns) is possible due to changing of LC contour parameters. Energy of generation reaches a maximum at use of small values of peaking capacity, which are significantly smaller then value of storage capacity.
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