1. DESTRUCTION OF PULSE TRAINS IN WEAKLY NONLINEAR OSCILLATOR D.D. Vavriv chaos, dynamical systems, train pulses, quasi linear oscillator Vestnik KhNU ¹756 Pages. 7178
A study has been carried out on the transition of train of pulses via a weakly nonlinear oscillator. Conditions of destruction of such trains as a result of appearance of chaotic instabilities have been analyzed. Analytically conditions of the appearance of chaotic instabilities have been determined by using the method of secondary averaging.
2. Determena Frequency properties of intervalley electron transfer in AlN V. T. Plaksiy, À.V.Arhipov, À. S. Tischenko, Ò. ². Kamishanova, E.D. Prokhorov, À.V.Dyadchenko, D. P.Chueshkov perfect crystal, zone overcrystallization, temperature gradient Vestnik KhNU ¹966 Pages. 1922
The problem of growing of perfect bismuthantimony monocrystals having of a uniform distribution of Sb atoms through the crystal by help floatingzone refining method is considered. The expression for temperature gradient in melt and temperature distribution for any melt point have been obtained.
The monocrystals growing maximal velocity have been estimated. The growing velocity must be lower then 1 mm per hour was showed. It is velocity not lead to concentration overcooling and arising inhomogeneous dendrite structure. For solution with certain composition ( at = const) overcooling may be eliminated by either increasing of temperature gradient in liquid faze or decreasing growing velocity are showed.
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3. Determination of optimal parameters of a magnetocardiographic hexagonal measuring grid A.Yu. Kostiev, A.Yu. Butrym, S.N. Shulga magnetocardiography, gradiometer, current dipole, sensitivity, Hessian Vestnik KhNU ¹883 Pages. 2529
The article considers hexagonal grid of gradiometer sensors of magnetic field. The aim of the study is to determine the optimal parameters of the grid and the gradiometers in order to obtain maximum sensitivity of the measuring system in terms of location
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4. Dielectric permittivity profile reconstruction by frequency probing problem for a planelayered media with regard to dispersion Batrakov D.O., Simachov O.A. plane layered media, dispersion, inverse problem, dielectric permittivity Vestnik KhNU ¹883 Pages. 4549
In the present paper the problem of dielectric permittivity profile reconstruction with regard to dispersion is discussed. The nature of dispersion function is assumed to be known and unknown functions are real and imaginary parts of dielectric permittivi
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5. Diffraction of the plane acoustic wave on the hard spherical segment, shielding of the ball Rezunenko V.A. acoustics, spherical segment, shielding ball, resonance frequencies, algebraic equations of the second kind Vestnik KhNU ¹853 Pages. 5763
A solution of the axisymmetrical problem of acoustics in strict formulation is built. The acoustic potential of the velocity of the plane wave, diffracted on the hard spherical circular segment, shielding of the ball is analyzed. The method of regularization of the paired summarized equations is used. The method of the integral transformations is applied. The principal part of the summarized equations is isolated and inverted. The effectively solvable system of the linear algebraic equations of the second kind with the compact operator in the Hilbert space l_{2} is obtained. Comparison with the known results and limited cases of the problem is given. The effectiveness of the constructed algorithm is confirmed. Some resonance frequencies and generalization of the task are examined
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6. Directed and polarization characteristics of the aperture of the circular waveguide with impedance flange N.N. Gorobets, V.M. Dakhov, I.V. Gorbach microwave, antennas, waveguides, polarization, pattern Vestnik KhNU ¹806 Pages. 37
The amplitude and polarization patterns of the radiator in the form of the aperture of circular waveguide with impedance flange, excited by the dominant wave, have been measured by the method of the indicator antenna with polarization plane rotation. It is shown that such radiators have an axialsymmetric pattern, a wide polarization pattern and a low level of side lobes.
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7. Directivity characteristics of rarefied antenna arrays N.N. Gorobets, A.A. Bulgakova electromagnetic waves, antennas, antenna array, directivity characteristics Vestnik KhNU ¹834 Pages. 8994
The radiation pattern, directive gain and scattering coefficient of equivedistance linear array were calculated and their dependencies on the number of radiators and distances between them were analyzed. It is shown that for every number of radiators the optimal antenna length of L≈0,9(N1), allowing to obtain the maximum of directive gain, occurs. For greater antenna length or increase in operating frequency, directive gain varies according to oscillating dependencies. The greater number of radiators occurs, the greater difference of maximums and minimums occurs. For small number of radiators (N≤8), the directivity characteristics of the array is higher, then for continuous antennas of the same electrical length. For N≥16, their characteristics coincide
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8. 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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