scholarly journals Propagation of low-frequency electromagnetic waves across a multilayer cylindrical shell

2014 ◽  
Vol 31 (86(4/14)) ◽  
pp. 467-481
Author(s):  
Viktor EROFEENKO ◽  
Aleksandr KUTS ◽  
Gennady SHUSHKEVICH
1991 ◽  
Vol 46 (1) ◽  
pp. 99-106 ◽  
Author(s):  
S. K. Sharma ◽  
A. Sudarshan

In this paper, we use the hydrodynamic approach to study the stimulated scattering of high-frequency electromagnetic waves by a low-frequency electrostatic perturbation that is either an upper- or lower-hybrid wave in a two-electron-temperature plasma. Considering the four-wave interaction between a strong high-frequency pump and the low-frequency electrostatic perturbation (LHW or UHW), we obtain the dispersion relation for the scattered wave, which is then solved to obtain an explicit expression for the growth rate of the coupled modes. For a typical Q-machine plasma, results show that in both cases the growth rate increases with noh/noc. This is in contrast with the results of Guha & Asthana (1989), who predicted that, for scattering by a UHW perturbation, the growth rate should decrease with increasing noh/noc.


2018 ◽  
Vol 46 (2) ◽  
pp. 225-229
Author(s):  
Hua Huang ◽  
Xiao-Tian Gao ◽  
Xiao-Gang Wang ◽  
Zhi-Bin Wang

Author(s):  
Florin IMBREA ◽  
Branko MARINCOVIC ◽  
Valeriu TABĂRĂ ◽  
PAUL PÎRŞAN ◽  
Gheorghe DAVID ◽  
...  

Experimenting new technology of cultivating maize is an important step forward in order to optimise the yielding capacity if a crop that ranks second among crops cultivated worldwide and first among crops cultivated in Romania. Using low frequency radiations to stimulate yield and quality in maize allows increases in yield between 10 and 15% compared to the classical cultivation method and an improvement of the quality indicators (protein content increased with 6-11% determining an increase of the protein yield per ha; starch content increased with 7-14%, which also determined an increase of the starch yield per ha; while fat content, another indicator we monitored, increased with 2-6%).


Author(s):  
C. Béghin ◽  
G. Wattieaux ◽  
R. Grard ◽  
M. Hamelin ◽  
J. P. Lebreton

Abstract. This works presents the results obtained from an updated data analysis of the observations of Extremely Low Frequency (ELF) electromagnetic waves performed with the HASI-PWA (Huygens Atmospheric Structure and Permittivity, Wave and Altimetry) instrumentation after Huygens Probe landing on Titan surface in January 2005. The most significant signals observed at around 36 Hz throughout the descent in the atmosphere have been extensively analyzed for several years, and subsequently interpreted as the signature of a Schumann resonance, although the latter exhibits atypical peculiarities compared with those known on Earth. The usual depicting methods of space wave data used so far could not allow retrieving the presence of weak signals when Huygens was at rest for 32 min on Titan's surface. Whereas the expected signal seems hidden within the instrumental noise, we show that a careful statistical analysis of the amplitude distribution of the 418 spectral density samples of the 36 Hz line reveals abnormal characteristics compared to other frequencies. This behavior is shown to occur under propitious circumstances due to the characteristics of the onboard data conversion processes into digital telemetry counts, namely 8-bit dynamic after logarithm compression of the DFT (Discrete Fourier Transform) of ELF waveforms. Since this phenomenon is observed only at the frequency bin around 36 Hz, we demonstrate that the Schumann resonance, seen in the atmosphere within the same band, is still present on the surface, albeit with a much smaller amplitude compared to that measured before and a few seconds after the impact, because the electric dipole is thought to have been stabilized ten seconds later almost horizontally until the end of the measurements.


2014 ◽  
Vol 1079-1080 ◽  
pp. 882-886 ◽  
Author(s):  
Fu Chien Kao ◽  
Shin Ping R. Wang ◽  
Yun Kai Lin ◽  
Chih Chia Chen ◽  
Chih Hsun Huang

In the era of wireless communication, WiFi becomes an indispensable accessory to most of us. People use WIFI to interact with the wireless Internet, perform commercial and financial transactions, or conducting recreational activities, etc.Though it offers a more convenient life to people, the strong Electromagnetic waves(EMW) resulted from it endangers human health, that has already turned out to be the primary study for medical science. Furthermore, EMW also attracts concern and panic of the inhabitants living in the surroundings which is filled with high-frequency and low-frequency EMwave. EMW today comes from broadcast towers, the system of the wireless communication, GPS, TVs and defense satellites mostly. Enjoying the convenience resulted from communication technology, people nowadays should also concern about whether EM wave would damage people’s health at the same time. Based on the perspective of cognitive neuroscience, this study mainly focuses on how EM wave produced from WiFi affects subject’s brainwaves under a specific physiological situation. The researcher observes different changing of brainwave when human beings expose in various strength of EM wave, and analyses the affection of EMW toward subject’s brainwaves.


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