1. Same question of modeling of tunnel contact semiconductor structure O.V. Botsula, E.D. Prokhorov tunnel cathode, negative differential conductivity, contacts, current  voltage characteristics, cathode, anode Vestnik KhNU ¹712 Pages. 119122
Electronic processes are considered at course of a current through semiconductor structure with the tunnel cathode. The approach to modelling the structures including as a component tunnel geterojunction is offered. Static characteristics of structures to a basis geterojunction GaAs/AIGaAs received with application of the offered technique are resulted
2. SCATTERING AMLITUDE ERROR ESTIMATION FOR MOMENT'S METHOD IN L_{2} FOR 2D SCREENS A.G. Tyzhnenko, Y.V. Ryeznik testing, reference solution, moment's method, 2D screens Vestnik KhNU ¹756 Pages. 6570
The scattering amplitude error estimation problem for practically used MoM solutions in L_{2} function space for scattering from 2D screens is addressed. To this end, a rigorous Galerkin solution in L_{2} 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 illconditioning connected with high mesh density for any MoM solution to the EFIE in L_{2}. Using the approach, the asymptotic decay rate of scattering amplitude error is investigated for some MoM algorithms widely used in practice
3. Scattering electromagnetic waves by coupling aperture of electrodynamic volumes in presence of finite sizes impedance body M.V. Nesterenko impedance vibrator, narrow slot, distributed surface impedance, rectangular waveguide Vestnik KhNU ¹712 Pages. 4751
Systems of integraldifferential equations concerning surface equivalent magnetic and electrical currents which are excited with impressed sources of electromagnetic field in the coupling aperture of electrodynamic volumes and in the finite sizes impedance body have been obtained. The approximate analytical solution of the equations system for the narrow transverse slot in the broad wall of rectangular waveguide with the thin impedance vibrator was represented. Also theoretical and experimental graphs of electrodynamic characteristics of such structure in dependence on the wavelength in the base oscillations band the waveguide was represented
4. Selection of the highorder modes in the waveguide resonator by means a phaseshifting mirror A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov waveguide quasioptical resonator, excitation of the highorder transverse modes, a phase filter, Fourier optics, selection Vestnik KhNU ¹806 Pages. 8791
The method of the space Fourierfiltration for selective excitation of separated highorder modes in the metal waveguide quasioptical resonator with a high discrimination degree of undesirable modes is realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes for the metal resonators of the submillimeter laser from resonator geometric sizes and parameters of the phase filter on the nonuniform mirror. Configurations of the phaseshifting mirrors for shaping of the highorder transverse modes in the laser resonators containing waveguides and open parts are proposed
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5. SELECTIVE excitation of the HIGHorder MODES IN THE waveguide quasioptical RESONATOR A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov waveguide quasioptical resonator, excitation of the highorder transverse modes, an amplitude filter, Fourier optics Vestnik KhNU ¹756 Pages. 123131
The method of the space Fourierfiltration for selective excitation of separated highorder transverse modes in the waveguide quasioptical resonator with a high discrimination degree of undesirable modes is proposed and realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes of the dielectric and metal resonators of the submillimeter laser from geometric sizes of reflectors and parameters of the space filter on the nonuniform mirror. Configurations of the amplitudestepped mirrors for shaping the highorder transverse modes in the laser resonators containing waveguides and open parts are proposed
6. Signal scattering on the meteor trail Kharchenko H.V. signal scattering, meteor trail, diffraction oscillations, electron density, plasma collective interaction, impulse response. Vestnik KhNU ¹966 Pages. 9096
A generalized model of the radiosignal scattering on the meteor trail is proposed. The model allows to take into account the process of formation and development of the meteor trail, and to calculate the scattered signal power change without sharing the meteor trails on underdense and overdense. As input parameters of the model used the physical parameters of the meteoroid  the mass and velocity, which determine the ionization of the plasma formation, as well as the location and orientation of the meteor trail. In the derivation of the analytical relations taken into account the presence of the plasma sheath surrounding the 'metal cylinder' and the collective interactions in the plasma. In the paper shown that the results of calculations are in good agreement with observations.
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7. 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 ¹853 Pages. 5156
In this work the excitation of a semiinfinite perfectly conducting cone with periodic longitudinal slots by an impulse radial source problem is investigated. The solution of the wellposed initialboundary problem is found using an analytically numerical method based upon Green function and MelerFock 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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8. 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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9. SPECKLE – INTERFEROMETRICIAN METHOD FOR ANEMOMETRICIAN OF TURBULENT STREAMS G.N. Dolya, À.N. Katunin, Ê.V. Sadovy, S.I. Shmatkov , speckle – interferometrician, anemometrician, speckle – painting, lightreflecting coverage Vestnik KhNU ¹756 Pages. 118122
In this paper is researched the possibility of the use of the modified speckle – interferometrician method for anemometrician of turbulent streams. It is developed laser anemometer on the basis of the modified speckle – interferometrician method at the applications of lightreflecting coverage. Is dependence of increase of border frequency of signal’s spectrum at growth of speed of stream transversal to the ray. Dependence of spectrum of fluctuations the adopted signal on the degree of the brought distortions in at a different temperature of turbulent stream is explored
10. 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 ¹712 Pages. 127131
Based on the model considerations it was shown that irradiation of liquids containing gas inclusions with electromagnetic fields of "slowlyconvective" intensity is conducive to the changes in the inclusion size
11. Stochastic fields optimal processing in MPSAR A.V. Ksendzuk multiposition system, synthetic aperture, stochastic model, combined estimation Vestnik KhNU ¹712 Pages. 3032
This paper represents optimal combined estimation algorithm in multiposition synthetic aperture radar as signed for estimation of the parameters, contained in correlation function of the complex scattering coefficient; the most important special cases were presented
12. Structure and the contents of the hypertext databaseof problems of remote sounding of the ground from space L.M.Atroshenko, N.N.Gorobets, L.P.Safronova, S.A.Smirnov ðroblems of remote sensing, a database Vestnik KhNU ¹834 Pages. 4251
The principle of construction and filling of a hypertext database of problems of remote sensing of the Earth from Space including more 4000 problems RSE are described. The approach to an optimum choice of a sensor control is illustrated by the examples of use of active and passive sounding in a radiorange
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13. Subterahertz diffraction radiation on the BWO frequency harmonics in the parametrical tworegimes electron device E.N.Odarenko, A.A.Shmat’ko, P.V. Yudintcev diffraction radiation, SmithPurcell effect, subterahertz waves, beamwave interaction, nonlinear processes Vestnik KhNU ¹834 Pages. 1317
Diffraction radiation nonlinear theory that takes into account tworegimes interaction – selfconsistent 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 selfconsistent equations set numerical solution. Ranges of the task parameters values that correspond to tworegimes interaction are defined
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