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In this study, one method of using antennas based on fractals to cover few kinds of public protection and disaster relief (PPDR) communications was presented. Dedicated antenna forms, necessary for antenna design by 5G implementation, were enhanced to suit ...
In the framework of Higgs inflation, we consider the electromagnetic field nonminimally coupled to gravity via the parity-preserving proportional to RF2 and parity-violating proportional to RF (F) over tilde terms. Using the perturbation theory to the lead ...
A recent study pointed out that macroscopic dark matter (macros) traversing through the Earth’s atmosphere can give rise to hot and ionized channels similar to those associated with lightning leaders. The authors of the study investigated the possibility t ...
In addition to a reduced number of feeders, which would simplify their integration in the cryostat of the tokamak, the present study considers the possibility to reduce the voltage during safety discharge of the toroidal field (TF) coils. A lowered dischar ...
We report the observation of three negative upward flashes recorded by a high-speed camera at the Säntis Tower during the Summer of 2019. The camera was operating at 10,000 fps and an exposure time of 99 μs. Simultaneous measurements of the lightning curre ...
Dealing with realistic networks, the solution of lightning electromagnetic field coupling to transmission lines is generally obtained through a Finite-Difference Time-Domain (FDTD) algorithm interfaced with an electromagnetic simulator. As well known, the ...
This letter sets out to describe the first results of the design process that will lead to a new on-line partial discharge location method based on Electromagnetic Time Reversal theory and using the Transmission Line-Matrix method. A description of the bas ...
Upward lightning occurs generally from tall structures. The mechanism of the initiation of upward lightning is not yet fully understood. Upward lightning can be classified into two categories based on either the absence or the presence of other lightning a ...
Upward lightning is the dominant type of lightning discharge to tall structures. It has been observed that a significant number of these upward flashes are initiated by nearby lightning activity. The aim of this study is to estimate the incidence of upward ...
An ultralow-profile circularly polarized (CP) reflectarray (RA) antenna is presented in this article, based on the variable-rotation technique for beam collimation and scanning. Starting from a conventional split-loop element, a new wideband element is des ...