M.V. Balaban
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
The Mathematical Model of Electromagnetic Wave Diffraction by a Resistive Disk
The problem of diffraction of an electromagnetic wave by a resistive infinitely thin disk is considered. The rigorous mathematical model of this problem, i.e., the set of coupled dual integral equations is built. This set is integrated and equivalently reduced to the pair of “canonical” dual integral equations which is equivalent to the Fredholm second kind integral equations.

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Yu.V. Svishchov
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Regularization of a Boundary Value Problem of an Arbitrary Scalar Wave Diffraction by the Spherical Segment. The Neumann Problem

The problem of an arbitrary scalar wave diffraction by a spherical shield with a circular aperture is considered (the Neumann problem). Resonance and scattering characteristics of plane wave scattering have been investigated. In particularly, the intermode coupling phenomenon in a sphere with a circular aperture has been found.

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A.Ya. Kirichenko, A.E. Kogut, Yu.V. Bludov, G.V. Golubnichaya, V.V. Kutuzov, I.G. Maximchuk, and V.A. Solodovnik
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Metal Mirror Influence on Forced Whispering Gallery Oscillations in a Hemispherical Dielectric Resonator
A frequency spectrum of H-modes of a dielectric hemispherical resonator has been studied with a metal mirror in an equatorial plane and in the absence of a mirror. It has been found that, in contrast to E-mode oscillations, H-mode oscillations can be also excited in absence of a metal mirror. This fact was previously considered to be impossible and in doing so the rarefaction of a spectrum and increase in a quality factor of resonant oscillations have been observed. Moreover, boundaries of regions of localization of whispering gallery EM fields and distribution of their intensity along a surface of a dielectric resonator have been ascertained.

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P.G Dalchenko1, M.I. Dzyubenko2, V.F. Pedash1, and Yu.F. Pedash1 1V. Karazin National University of Kharkiv,
4, Svoboda Sq., Kharkiv, 61077, Ukraine
2A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Comparative Analysis of Singlet and Excited States of Xanthene and Oxazine Dyes
Calculations of the exited states of ionic forms of xanthene and oxazine dyes are carried out in the ï-electron approximation. Electron transition energies, their polarization and electron density redistribution in the exited states are evaluated. The use of charge transfer numbers allowed us to establish a genetic bond of exited singlet states of xantene and oxazine compounds. Quantitative characteristics of the donor activity of substituents (amine- and oxy-groups) are obtained and their contribution to the formation of excited terms is determined with the use of localization numbers.

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V.A. Goryashko1, K.V. Ilyenko1, and A.N. Opanasenko2
1A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv, 61085, Ukraine
2National Science Center “Kharkiv Institute of Physics and Technology”
National Academy of Sciences of Ukraine
1, Akademichna Str., Kharkiv, 61108, Ukraine
Renormalized Resonant Conditions for a Hybrid Weakly-Relativistic Waveguide Free-Electron Laser

We propose an analytical technique of twofold perturbation expansion to solve the nonlinear equations of motion of weakly-relativistic electrons moving in the magnetostatic pump field of a hybrid planar free-electron laser and apply it to obtain linear corrections to the electron trajectories caused by interaction with given propagating modes of a circular waveguide. In the nonlinear part of the problem, existing trajectory resonances are studied and their accessibility is numerically investigated. In a single-particle approximation the conditions of the most efficient interaction between an electron beam and propagating modes of a circular waveguide (resonant conditions) are derived analytically using small-signal theory in the microwave field. These conditions contain 'renormalization' multipliers, which are responsible for enforcement of energy conservation conditions if the microwave field is neglected.

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V.I. Ponomaryov, J.L. Sanchez-Ramirez and C. Juarez-Landin
National Polytechnic Institute of Mexico
Evaluation and Optimization of the Standard JPEG2000 for Compression of Ultrasound Images

This work presents the method of the optimization stage in cuantizacion for compression standard JPEG2000. We applied the proposal for compression of the ultrasound images. Previous to the optimization it has been carried out several tests; firstly for determination which of the three implementations of the standard (Jasper, Morgan JPEG Toolbox and Kakadu) can be used. The selected implementation is used to determine some optimal parameters to compress this type of images as for the Wavelet used as the number of decomposition levels. Finally, it was realized the optimization, in the cuantizacion stage of compression.

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V.I. Ponomaryov, F.J. Gallegos-Funes, R. Sansores-Pech, and L. Nino-de-Rivera
National Polytechnic Institute of Mexico, Mexico
Noise Reduction in 3D Real-Time Ultrasound Imaging
This paper presents an approach based on order statistics for speckle and impulsive noise reduction in the 3-D ultrasound images. The technique uses the Rank M-type (RM) estimators that are adapted to 3-D image processing applications. The theory and real-time implementation on the DSP TMS320C6711 are presented by use real clinical ultrasound images. The results from known techniques are compared with the proposed method to demonstrate its performance.

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S.V. Plaksin and I.I. Sokolovsky
Institute for Transport Systems an Technologies
National Academy of Sciences of Ukraine
5, Pisarzhevskogo Str., Dnipropetrovsk 49005, Ukraine
The Contactless Method for Determining the Spatial Position of a Magnetically Levitated Vehicle

A study has been made of an active-oscillator sensor for measuring minor displacements and their deviations between mobile objects. The sensor is built around two microwave (MW) oscillators, one of which is a reference device. The oscillation frequency of the other that simultaneously acts as a mixer is governed by the variation in the phase distance between objects. The difference frequency is said to be informative criterion of the maximum sensitivity of sensor is determined.

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