1. Method of finding permittivity, volume characteristics and hydratation of components of water solutions
L.M. Atroshenko, N.N. Gorobets, L.P. Safronova
dielectric permittivity, Bound water, hydration, specific volume, density
Vestnik KhNU ¹712 Pages. 17-20
A method for calculation of permittivity of bound water, hydration of substances, volume shares and specific volumes of water solution components, based on data of measurements of the complex permittivity and solution densities, was suggested
2. The influence of the inner chanal of a periodic iris-loaded circular waveguide concerning its eigenmode mutual transformations
He Shi, S.K. Katenev, S.N. Shulga
dispersion, Brillouin diagram, mode transformation
Vestnik KhNU ¹712 Pages. 80-83
The mutual eigenmode transformations are considered of a periodic iris-loaded circular waveguide against variations or its inner radius, using BriUouin diagram characteristics. The specific features of the waveguide regular and periodicity modes of Eo,and asymmetric waves are pointed out
3. 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 ¹756 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.
4. Electrons in superlattice with continuous conduction band edge
M.V. Klymenko, S.I. Petrov
superlattice, effective mass, Bragg effect, carriers confinement
Vestnik KhNU ¹756 Pages. 91-96
In this paper, the energy spectrum of electrons is investigated for the superlattice with continuous conduction band edge. The comparison with conventional superlattice has been realized. It is shown that in the investigated structure the energy spectrum has band structure which is caused by periodic position-dependent effective-mass. Moreover, position-dependent effective-mass leads to additional effective potential. The Bragg reflection for electrons in ballistic limit can be observed in the superlattice with continuous conduction band edge. It can be used for effective Bragg confinement of carriers. For the first time the investigations have been carried out for the case when the superlattice without band offsets has finite number of periods. The obtained results shed light on new applications of the investigated structures for THz frequency range
5. 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 ¹756 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.
6. THE H10 WAVE SCATTARING BY THE THIN VARIABLE RADIUS IMPEDANCE VIBRATOR IN A
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 ¹806 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
7. RECTANGULAR WAVEGUIDE M.V.
millimeter range, parametric amplifier, oscillatory system, Band of the reinforcement, relative noise temperature
Vestnik KhNU ¹806 Pages. 18-21
Semiconductor two-stage parametric amplifiers have been developed to be used in the input circuits of communication and navigation systems in the short-part of millimeter wave band. In the 60 to 65 GHz range, the gain is no worse than 15 dB at -3 dB level in 1 to 1.6 GHz bandpass. The noise temperature is no higher than 500K when the quasi-optical IMPATT oscillator is in using as the pumping generator.
8. Subterahertz diffraction radiation on the BWO frequency harmonics in the parametrical two-regimes electron device
E.N.Odarenko, A.A.Shmat’ko, P.V. Yudintcev
diffraction radiation, Smith-Purcell effect, subterahertz waves, Beam-wave interaction, nonlinear processes
Vestnik KhNU ¹834 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
9. Far-field distance of waveguide radiators
N.N. Gorobets, E.E. Ovsyannikova, A.V. Shishkova
rectangular waveguide, microwaves, Boundary of far zone, amplitude, phase radiation characteristics
Vestnik KhNU ¹834 Pages. 68-76
On the basis of Hertz potentials in Kirchhoff approximation the amplitude and phase radiation characteristics of open-ended rectangular waveguide excited by TE10 dominant mode are investigated at arbitrary distance from radiating aperture. The estimation criteria of far zone boundary for small (in comparison with the wavelength) waveguide radiators are presented. For such small radiators, the classic formula for calculation of far-field distance cannot be applied. Under suggested criteria the investigation of radiation characteristics are carried out. For waveguides with the sizes less then the wavelength in the waveguide, the boundaries of far-field distance are defined
10. Potentially unbreacable ciphering on a hybrid physical-mathematical level
A. G. Tyzhnenko, E. V. Ryeznik
Bit, stochastic signals, safe communication, hard drive protection
Vestnik KhNU ¹834 Pages. 108-113
A new kind of ciphering based on stochastic representation of bits as series of samples is addressed. Stochastic comparison is used for bit identification. Security level is increased by adding noise samples to signal samples and mixing signal samples with noise samples within one signal packet. The signal packet length and distribution features of signal samples among noise samples in signal packets are unique for given communication line, as well as stochastic representation of bits (0s and 1s). Using of noise in signal packets leads to enormous large computation in decrypting process which is unrealistically to do regardless what computer system is used. More to the point, the unique features of communication line mentioned above can be changed for each message that prevents information leakage in the case of stealing these ones in any previous period. Impossibility of decrypting by any reasonable time period of any message eavesdropped by a cryptanalyst guarantees the confidence of information which has permanent importance
11. Capacitance-voltage measurements in selectively doped ALGAAS/GAAS heterostructures
N.B.Gorev, I.F. Kodzhespirova, E.N. Privalov
gallium arsenide, selectively doped heterostructures, Schottky barrier, Barrier capacitance, capacitance–voltage measurements
Vestnik KhNU ¹853 Pages. 3-7
The dependence of the measured apparent capacitance of selectively doped AlGaAs/GaAs heterostructures on the amplitude of the measuring ac voltage is calculated numerically. An expression that gives the measured apparent capacitance as a function of the true capacitance and the above amplitude is derived. Using this expression and the results of the above numerical calculation, it is shown that capacitance–voltage characteristics of selectively doped AlGaAs/GaAs heterostructures, which feature steeply dropping regions, may be measured at moderately small amplitudes of the measuring ac voltage (of the order of 100 mV) at the expense of taking measurements at two different amplitudes
12. Algorithms of the processing signal from the trellised receiver for measuring of the laser radiation characteristics
Kokodiy N.G., Pak A.O.
the laser, optical radiation, intensity, Bolometer, direct task, reverse task
Vestnik KhNU ¹853 Pages. 37-44
In this paper has been considered the development of the device for the measurement of the intensity distribution in the beam of optical radiation. The algorithm of processing of a signal from the receiver of radiation is studied. The method of measurement of the intensity distribution of optical radiation by the bolometric grid is offered. The developed algorithms for processing a signal from the measuring converter and programs realizing them are checked up experimentally, their serviceability is confirmed. The comparative characteristic of algorithms based on the transformation of Fourier and transformation of Radon has shown an opportunity of their use in practice
13. Ballistic electronic transport in continuous-band superlattice under applied electrostatic field
S.I.Petrov, Klymenko M. V., Shulika O. V.
Ballistic transport, superlattice, effective potential
Vestnik KhNU ¹883 Pages. 12-19
We address in this work ballistic transport of electrons in semiconductor continuous-band superlattice under applied electrostatic field. Combined influence of the effective mass periodically varied in space and external electrostatic field on the electro
14. NonstationarY processes in the hybrid O-type beam-wave system
Odarenko E.N., Shmatko A.A.
nonautonomous oscillatory system, locking, Beats
Vestnik KhNU ¹966 Pages. 23-30
Nonstationary processes in the resonant beam-wave system with pre-modulated electron beam are investigated in this work. Theoretical analysis is performed on the basis of the nonlinear multidimensional theory of the hybrid O-type electron devices. Basic regularities of the external signal power effect on the lock range width are described. Regimes of the oscillations synchronization, beats and squitter for different values of the oscillation system and ex-ternal signal parameters are considered.
15. Ðåøåò÷àòûé ïðèåìíèê äëÿ èçìåðåíèé õàðàêòåðèñòèê ëàçåðíîãî èçëó÷åíèÿ
Lizogubenko S.V., Kokodiy N.G.
scattering pattern, diameter of the particles, scattering, Brightness of the light spot, Beam intensity
Vestnik KhNU ¹966 Pages. 9-12
Considered the method of defining the size of microparticles using a digitized image of the scattering. For research the optical method is used It consists that the researched substance, consisting of microparticles, is illuminated with the beam of optical radiation and then the scattering of the transmitted light is registered. After this, the digital processing of resulting scattering pattern is carried out and held the measurement of particle size in two different ways.
16. 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 ¹966 Pages. 37-49
Mathematical models, computational algorithms, and also prospects of development and application of three new methods of recognition and classification (RÀC), 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.
Ballistic transport, superlattice, effective potential
Vestnik KhNU ¹883 Pages. 12-19
We address in this work ballistic transport of electrons in semiconductor continuous-band superlattice under applied electrostatic field. Combined influence of the effective mass periodically varied in space and external electro-static field on the electron transport leads to new undiscovered phenomena. We consider transport at the center of the Brillouin zone as well as off-center-zone transport. Results obtained open possibility for control of electron transport in semiconductor superlattices.
grid, Bolometer, intensity distribution, polarization, energy center, Beam diameter, generalized cross-sectional square of the beam.
Vestnik KhNU ¹983 Pages. 72-76
In this paper the grid receiver for measuring laser radiation characteristics has been considered. The receiver contains four grids located perpendicular to the direction of propagation. Wire elements are located at angles 0 , 45?, 90? and 135? to the vertical. One grid contains 8 nickel bolometers with diameter 40 microns, bolometers are located on 7.2 mm from each other. The diameter of the window – 60 mm. Intensity distribution in the space has been measured, therefore, the position of the energy center, the diameter, the generalized cross-sectional square of the radiation beam have been determined. The Radon transformation has been used as the mathematical basis of signal processing algorithms. Also the polarization direction and intensity distribution of polarized radiation have been measured by a numerical experiment.
wave equation, exact solutions, localized waves, Bateman solution, general astigmatism.
Vestnik KhNU ¹983 Pages. 77-83
A new class of exact non-harmonic in time solutions of 3D wave equation is established. This class is a generalization of the known complexified relatively undistorted Bateman-type solution, involving an arbitrary function, waveform. Argument of this function is much similar to that which appears in general astigmatic paraxial Gaussian beam. Special choices of the waveform allow general astigmatic beam-like and packetlike waves with Gaussian-type localization in space and time.
polarization converter, Bragg reflector, anisotropy
Vestnik KhNU ¹927 Pages. 43-47
Today, there are two fundamental type polarization converters, passive and active, are widely used in optical circuits. In this paper, we present a passive polarization converter for near infrared range. The converter reported here is porous silicon-based structure consists of N distributed Bragg reflectors (DBR) separated by N-1 defects. The method of the electromagnetic field’s scalarization and finite difference technique were used for calculation of spectral characteristics. The transmittance spectra of the proposed polarization converters for the both polarization of the incident plane wave are presented
radioholographic image, flat and unflat radiohologram, By volume image of object, effect of Dopler.
Vestnik KhNU ¹927 Pages. 48-53
The physical and structural features of construction of the radioholographic informative systems (RG IS) and their adaptive properties which show up at forming and treatment of the coherent wave field on a transmission and reception are examined. The method of registration of radiohologram is offered on the surfaces of arbitrary form and method of adaptation of frequency of supporting oscillation to different frequencies of signal at a cooperative reception and to frequency of Dopler.
founded: 21 result (s)