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Maltsev V.P.,Institute for Radiophysics and Electronics of NAS of Ukraine
YSF 2015 - International Young Scientists Forum on Applied Physics | Year: 2015

At the end it is possible to make the following conclusions: 1. The noncontact sensor on the base of coherent radar in CW mode and contact sensor which uses hall effect are developed for measurement of agriculture vehicle slip coefficient. 2. Use of such sensors provides optimal choice of the vehicle speed to minimize fuel consumption by control of the slip coefficient (difference between output data of the contact and noncontact sensors). 3. The design of both sensors is described and the algorithm of signal processing in the time-frequency domain is discussed. 4. For signal processing the special unit is developed on the base of microprocessor that realizes the algorithm described. 5. The preliminary experimental data are cited and the results of full scale tests are shown that confirmed the functioning of the sensors developed. © 2015 IEEE.

Ilyenko K.,Institute for Radiophysics and Electronics of NAS of Ukraine | Kurkin S.A.,Chernyshevsky Saratov State University | Hramov A.E.,Saratov State Technical University | Opanasenko A.,National Science Center Kharkov Institute of Physics and Technology
CriMiCo 2013 - 2013 23rd International Crimean Conference Microwave and Telecommunication Technology, Conference Proceedings | Year: 2013

We obtained representations for static electric and magnetic fields induced by charged-particle current in a regular simply connected ideally conducting waveguide in the form of solutions to excitation equations of Kisunko-Vainshtein waveguide excitation theory. On the example of a regular rectangular waveguide an equivalence of the obtained expressions with Green's function representations of these fields is demonstrated. © 2013 CriMiCo'2013 Organising Committee, CrSTC.

Panin S.B.,TUBITAK - Marmara Research Center | Turetken B.,TUBITAK - Marmara Research Center | Poyedinchuk A.Y.,Institute for Radiophysics and Electronics of NAS of Ukraine | Tuchkin Y.A.,Gebze Institute of Technology
Progress In Electromagnetics Research B | Year: 2014

Theoretical results on the electromagnetic wave diffraction from a periodic strip grating placed on a chiral medium are obtained. Analytical Regularization Method based on the solution to the vector Riemann-Hilbert boundary value problem was used to get robust numerical results in the resonant domain, where direct solution methods typically fail. It was shown that in the case of normal incidence of linearly polarized wave the cross-polarized Field appears in the reflected Field. For elliptically polarized incident wave the diffraction character essentially depends on the polarization direction of the incident wave. These diffraction peculiarities are more pronounced in the resonant domain. Influence of the dichroism caused by chiral medium losses is thoroughly studied. The combination of a chiral medium and a grating can be effectively used for a frequency and polarization selection and for a mode conversion.

Fedorin I.,Kharkiv Polytechnic Institute | Bulgakov A.,Institute for Radiophysics and Electronics of NAS of Ukraine
International Conference on Mathematical Methods in Electromagnetic Theory, MMET | Year: 2012

Conical refraction phenomenon in a fine-stratified structure was studied. The structure was fabricated by periodic alternating dielectric and semiconductor layers and was exposed into an external magnetic field parallel to the boundaries of the layers and perpendicular to the plane of incidence. The expressions for effective permittivity were obtained. It has been shown that such structure represents a biaxial crystal. The dependences of aperture angles of an external and internal conical refraction cone as function of frequency, external magnetic field and thickness of layers were analysed. © 2012 IEEE.

Goryashko V.A.,Institute for Radiophysics and Electronics of NAS of Ukraine
Physical Review Special Topics - Accelerators and Beams | Year: 2011

Using a time-dependent approach, the analysis and optimization of a planar free-electron laser (FEL) amplifier with an axial magnetic field and an irregular waveguide is performed. By applying methods of nonlinear dynamics, a self-consistent reduced model of the FEL is built in a special phase space. This reduced model is the generalization of the Colson-Bonifacio model and takes into account the intricate dynamics of electrons in the pump magnetic field and the intramode scattering in the irregular waveguide. The reduced model and concepts of evolutionary computation are used to find optimal waveguide profiles. The numerical simulation of the original nonsimplified model is performed to check the effectiveness of found optimal profiles. To demonstrate advantages of the proposed FEL configuration, the parameters are chosen to be close to the parameters of the experiment, in which a sheet electron beam with the moderate thickness interacts with the TE01 mode of a rectangular waveguide. The results strongly indicate that one can improve the efficiency by a factor of 5 or 6 if the FEL operates in the magnetoresonance regime and if the irregular waveguide with the optimized profile is used. The FEL efficiency is maximal if the initial beam energy is slightly higher than the energy that corresponds to a transition between negative- and positive-mass regimes so that the transition from the negative-mass to positive-mass regimes occurs during the beam-wave interaction. © 2011 American Physical Society.

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