Velocity of Energy Characteristics of Electromagnetic Waves Emitted by Hertz Dipole Excited by Gaussian Pulse

2021 ◽  
Vol 64 (7) ◽  
pp. 351-362
Author(s):  
Victor I. Naidenko
Author(s):  
N. S. Petrov ◽  
S. N. Kurilkina ◽  
A. B. Zimin ◽  
V. N. Belyi

In this paper, it is shown that under the conditions of total internal reflection of plane homogeneous electromagnetic waves at the interface of a hyperbolic metamaterial and an ordinary isotropic medium, special inhomogeneous electromagnetic waves are excited in certain circumstances near the surface of the metamaterial and their amplitude changes with distance according to the non-exponential law. The existence conditions for such waves are established for the case when the optical axis is located within the interface plane and forms an angle with the plane of incidence. The energy flux and the energy density of special inhomogeneous waves in a hyperbolic metamaterial are determined. 


2019 ◽  
Vol 126 (3) ◽  
pp. 319 ◽  
Author(s):  
Н.С. Петров ◽  
С.Н. Курилкина ◽  
А.Б. Зимин ◽  
В.Н. Белый

AbstractThe boundary problem of reflection of electromagnetic waves by a hyperbolic metamaterial layer under conditions of total reflection from the boundary with this layer in the absence of birefringence has been solved. In this case, so-called “special inhomogeneous electromagnetic waves” may propagate in the layer. Analytical expressions are obtained for the vector amplitudes of the waves reflected by the layer and transmitted through it and for the special inhomogeneous electromagnetic waves propagating in this layer. These expressions allows calculating the energy characteristics of reflected and transmitted light for an optically uniaxial metamaterial.


2018 ◽  
Vol 16 (3) ◽  
pp. 229
Author(s):  
Branko Gvozdić ◽  
Dušan Đurđević ◽  
Nebojša Raičević

The convolutional perfectly matched layer (CPML) is currently, perhaps, the most efficient type of absorbing boundary condition in finite difference time domain method (FDTD) modeling of electromagnetic fields. The aim of this paper is to give a more detailed insight into parameter setting and absorption performance of CPML. In case of electromagnetic waves absorption for high-frequency impulsive source modeling, a proper choice of the CPML parameters is substantial. The numerical results show that stretching coefficient affects both absorption efficiency and dispersion. We demonstrate that, in order to eliminate dispersion, the stretching coefficient should be as small as possible. Additionally, the results have shown that a differentiated Gaussian pulse is a better choice than a regular Gaussian pulse in FDTD simulations.


1997 ◽  
Vol 161 ◽  
pp. 761-776 ◽  
Author(s):  
Claudio Maccone

AbstractSETI from space is currently envisaged in three ways: i) by large space antennas orbiting the Earth that could be used for both VLBI and SETI (VSOP and RadioAstron missions), ii) by a radiotelescope inside the Saha far side Moon crater and an Earth-link antenna on the Mare Smythii near side plain. Such SETIMOON mission would require no astronaut work since a Tether, deployed in Moon orbit until the two antennas landed softly, would also be the cable connecting them. Alternatively, a data relay satellite orbiting the Earth-Moon Lagrangian pointL2would avoid the Earthlink antenna, iii) by a large space antenna put at the foci of the Sun gravitational lens: 1) for electromagnetic waves, the minimal focal distance is 550 Astronomical Units (AU) or 14 times beyond Pluto. One could use the huge radio magnifications of sources aligned to the Sun and spacecraft; 2) for gravitational waves and neutrinos, the focus lies between 22.45 and 29.59 AU (Uranus and Neptune orbits), with a flight time of less than 30 years. Two new space missions, of SETI interest if ET’s use neutrinos for communications, are proposed.


Author(s):  
Anthony S-Y Leong ◽  
David W Gove

Microwaves (MW) are electromagnetic waves which are commonly generated at a frequency of 2.45 GHz. When dipolar molecules such as water, the polar side chains of proteins and other molecules with an uneven distribution of electrical charge are exposed to such non-ionizing radiation, they oscillate through 180° at a rate of 2,450 million cycles/s. This rapid kinetic movement results in accelerated chemical reactions and produces instantaneous heat. MWs have recently been applied to a wide range of procedures for light microscopy. MWs generated by domestic ovens have been used as a primary method of tissue fixation, it has been applied to the various stages of tissue processing as well as to a wide variety of staining procedures. This use of MWs has not only resulted in drastic reductions in the time required for tissue fixation, processing and staining, but have also produced better cytologic images in cryostat sections, and more importantly, have resulted in better preservation of cellular antigens.


1998 ◽  
Vol 1 (1) ◽  
pp. 45-52 ◽  
Author(s):  
M. Defos du Rau ◽  
F. Pessan ◽  
G. Ruffie ◽  
V. Vignéras-Lefebvre ◽  
J. P. Parneix

1984 ◽  
Vol 45 (C5) ◽  
pp. C5-167-C5-178
Author(s):  
A. J. Sievers ◽  
Z. Schlesinger ◽  
Y. J. Chabal

2020 ◽  
Vol 64 (1-4) ◽  
pp. 137-145
Author(s):  
Yubin Xia ◽  
Dakai Liang ◽  
Guo Zheng ◽  
Jingling Wang ◽  
Jie Zeng

Aiming at the irregularity of the fault characteristics of the helicopter main reducer planetary gear, a fault diagnosis method based on support vector data description (SVDD) is proposed. The working condition of the helicopter is complex and changeable, and the fault characteristics of the planetary gear also show irregularity with the change of working conditions. It is impossible to diagnose the fault by the regularity of a single fault feature; so a method of SVDD based on Gaussian kernel function is used. By connecting the energy characteristics and fault characteristics of the helicopter main reducer running state signal and performing vector quantization, the planetary gear of the helicopter main reducer is characterized, and simultaneously couple the multi-channel information, which can accurately characterize the operational state of the planetary gear’s state.


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