Isolation of the singular part of the electromagnetic field scatteredby objects with sharp edges and conic points

In this article we propose a method for overcoming a number of problems that may arise when solving scattering problems on objects of complex structure. This approach can be used for mathematical and numerical modeling of waveguide, emitting and scattering systems of various complexity.

Relativistic Study on the Scattering of e± from Atoms and Ions of the Rn Isonuclear Series

Calculations are presented for differential, integrated elastic, momentum transfer, viscosity, inelastic, total cross sections and spin polarization parameters S, T and U for electrons and positrons scattering from atoms and ions of radon isonuclear series in the energy range from 1 eV–1 MeV. In addition, we analyze systematically the details of the critical minima in the elastic differential cross sections along with the positions of the corresponding maximum polarization points in the Sherman function for the aforesaid scattering systems. Coulomb glory is investigated across the ionic series. A short range complex optical potential, comprising static, polarization and exchange (for electron projectile) potentials, is used to describe the scattering from neutral atom. This potential is supplemented by the Coulomb potential for the same purpose for a charged atom. The Dirac partial wave analysis, employing the aforesaid potential, is carried out to calculate the aforesaid scattering observables. A comparison of our results with other theoretical findings shows a reasonable agreement over the studied energy range.

Work-Energy Principle Based Characteristic Mode Theory for Wireless Power Transfer Systems

<p>Work-energy principle (WEP) governing wireless power transfer (WPT) process is derived. Driving power as the source to sustain a steady WPT is obtained. Transferring coefficient (TC) used to quantify power transfer efficiency is introduced.</p><p>WEP gives a clear physical picture to WPT process. The physical picture reveals the essential difference between transferring problem and scattering problem. The essential difference exposes the fact that the conventional characteristic mode theory (CMT) for scattering systems cannot be directly applied to transferring systems.</p><p>Under WEP framework, this paper establishes a CMT for transferring systems. By orthogonalizing driving power operator (DPO), the CMT can construct a set of energy-decoupled characteristic modes (CMs) for any pre-selected objective transferring system. It is proved that the obtained CM set contains the optimally transferring mode, which can maximize TC.</p><p>Employing the WEP-based CMT for transferring systems, this paper does the modal analysis for some typical two-coil transferring systems, and introduces the concepts of co-resonance and ci-resonance, and reveals some important differences and connections “between transferring problem and scattering problem”, “between co-resonance phenomenon of transferring systems and external resonance phenomenon of scattering systems”, and “between so-called magnetic resonance and classical electric-magnetic resonance”.</p>

Work-Energy Principle Based Characteristic Mode Theory for Wireless Power Transfer Systems

<p>Work-energy principle (WEP) governing wireless power transfer (WPT) process is derived. Driving power as the source to sustain a steady WPT is obtained. Transferring coefficient (TC) used to quantify power transfer efficiency is introduced.</p><p>WEP gives a clear physical picture to WPT process. The physical picture reveals the essential difference between transferring problem and scattering problem. The essential difference exposes the fact that the conventional characteristic mode theory (CMT) for scattering systems cannot be directly applied to transferring systems.</p><p>Under WEP framework, this paper establishes a CMT for transferring systems. By orthogonalizing driving power operator (DPO), the CMT can construct a set of energy-decoupled characteristic modes (CMs) for any pre-selected objective transferring system. It is proved that the obtained CM set contains the optimally transferring mode, which can maximize TC.</p><p>Employing the WEP-based CMT for transferring systems, this paper does the modal analysis for some typical two-coil transferring systems, and introduces the concepts of co-resonance and ci-resonance, and reveals some important differences and connections “between transferring problem and scattering problem”, “between co-resonance phenomenon of transferring systems and external resonance phenomenon of scattering systems”, and “between so-called magnetic resonance and classical electric-magnetic resonance”.</p>

Reciprocal Transformations in Relativistic Gasdynamics. Lie Group Connections

Reciprocal transformations associated with admitted conservation laws were originally used to derive invariance properties in non-relativistic gasdynamics and applied to obtain reduction to tractable canonical forms. They have subsequently been shown to have diverse physical applications to nonlinear systems, notably in the analytic treatment of Stefan-type moving boundary problem and in linking inverse scattering systems and integrable hierarchies in soliton theory. Here,invariance under classes of reciprocal transformations in relativistic gasdynamics is shown to be linked to a Lie group procedure.

Modern mine scattering systems

For years, mine weapons have been irreplaceable on the battlefield. Using of fully mechanized mine scattering systems made it possible to reduce the direct exposure of soldiers to the enemy's fire, minimize losses and significantly hasten the work. The article presents a comparative analysis of modern mine scattering systems, as well as outlined further research directions related to this topic. Key words: mine explosive barriers, mine scattering systems, pyrotechnic systems