scholarly journals The numerical simulation on ionospheric perturbations in electric field before large earthquakes

2014 ◽  
Vol 32 (12) ◽  
pp. 1487-1493 ◽  
Author(s):  
S. F. Zhao ◽  
X. M. Zhang ◽  
Z. Y. Zhao ◽  
X. H. Shen
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Electromagnetic Waves ◽  
Low Frequency ◽  
Topside Ionosphere ◽  
Ion Density ◽  
Frequency Wave ◽  
Theoretical Simulation ◽  
Electric And Magnetic Field ◽  
Large Earthquakes

Abstract. Many observational results have shown electromagnetic abnormality in the ionosphere before large earthquakes. The theoretical simulation can help us to understand the internal mechanism of these anomalous electromagnetic signals resulted from seismic regions. In this paper, the horizontal and vertical components of electric and magnetic field at the topside ionosphere are simulated by using the full wave method that is based on an improved transfer matrix method in the lossy anisotropic horizontally stratified ionosphere. Taken account into two earthquakes with electric field perturbations recorded by the DEMETER satellite, the numerical results reveal that the propagation and penetration of ULF (ultra-low-frequency) electromagnetic waves into the ionosphere is related to the spatial distribution of electron and ion densities at different time and locations, in which the ion density has less effect than electron density on the field intensity. Compared with different frequency signals, the minimum values of electric and magnetic field excited by earthquakes can be detected by satellite in current detection capability have also been calculated, and the lower frequency wave can be detected easier.

PEMANFAATAN RADIASI ENERGI TEGANGAN 150 KV UNTUK LAMPU LED PENERANGAN JALAN

Jurnal Teknik ◽  
2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Mauludi Manfaluthy
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
High Voltage ◽  
Low Frequency ◽  
Energy Utilization ◽  
World Health ◽  
Electromagnetic Signals ◽  
Health Organization ◽  
The Magnetic Field ◽  
Low Frequency Waves

WHO (World Health Organization) concludes that not much effect is caused by electric field up to 20 kV / m in humans. WHO standard also mentions that humans will not be affected by the magnetic field under  100 micro tesla and that the electric field will affect the human body with a maximum standard of 5,000 volts per meter. In this study did not discuss about the effect of high voltage radiation SUTT (High Voltage Air Channel) with human health. The research will focus on energy utilization of SUTT radiation. The combination of electric field and magnetic field on SUTT (70-150KV) can generate electromagnetic (EM) and radiation waves, which are expected to be converted to turn on street lights around the location of high voltage areas or into other forms. The design of this prototype works like an antenna in general that captures electromagnetic signals and converts them into AC waves. With a capacitor that can store the potential energy of AC and Schottky diode waves created specifically for low frequency waves, make the current into one direction (DC). From the research results obtained the current generated from the radiation is very small even though the voltage is big enough.Keywords : Radiance Energy, Joule Thief, and  LED Module.

scholarly journals Comment on "Ultra low frequency (ULF) electromagnetic anomalies associated with large earthquakes in Java Island, Indonesia by using wavelet transform and detrended fluctuation analysis" by Febriani et al. (2014)

2015 ◽  
Vol 15 (12) ◽  
pp. 2697-2701 ◽  
Author(s):  
F. Masci ◽  
J. N. Thomas
Keyword(s):  
Magnetic Field ◽  
Detrended Fluctuation Analysis ◽  
Field Data ◽  
Low Frequency ◽  
Fluctuation Analysis ◽  
Geomagnetic Disturbances ◽  
Magnetic Field Data ◽  
Seismic Origin ◽  
Detrended Fluctuation ◽  
Large Earthquakes

Abstract. We examine the recent report of Febriani et al. (2014) in which the authors show changes in ULF magnetic field data prior to the M7.5 Tasikmalaya earthquake that occurred south of Java, Indonesia, on 2 September 2009. Febriani et al. (2014) state that the magnetic changes they found may be related to the impending earthquake. We do not agree that the pre-earthquake magnetic changes shown in Febriani et al. (2014) are seismogenic. These magnetic changes, indeed, are too closely related to global geomagnetic disturbances to be regarded as being of seismic origin.

scholarly journals Cometary ion dynamics observed in the close vicinity of comet 67P/Churyumov–Gerasimenko during the intermediate activity period

2018 ◽  
Vol 613 ◽  
pp. A57 ◽  
Author(s):  
L. Berčič ◽  
E. Behar ◽  
H. Nilsson ◽  
G. Nicolaou ◽  
G. Stenberg Wieser ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Electric Field ◽  
Field Measurements ◽  
Distribution Functions ◽  
Activity Period ◽  
Ion Density ◽  
Ion Flow ◽  
Velocity Distribution Functions ◽  
Comet 67P

Aims. Cometary ions are constantly produced in the coma, and once produced they are accelerated and eventually escape the coma. We describe and interpret the dynamics of the cometary ion flow, of an intermediate active comet, very close to the nucleus and in the terminator plane. Methods. We analysed in situ ion and magnetic field measurements, and characterise the velocity distribution functions (mostly using plasma moments). We propose a statistical approach over a period of one month. Results. On average, two populations were observed, separated in phase space. The motion of the first is governed by its interaction with the solar wind farther upstream, while the second one is accelerated in the inner coma and displays characteristics compatible with an ambipolar electric field. Both populations display a consistent anti-sunward velocity component. Conclusions. Cometary ions born in different regions of the coma are seen close to the nucleus of comet 67P/Churyumov–Gerasimenko with distinct motions governed in one case by the solar wind electric field and in the other case by the position relative to the nucleus. A consistent anti-sunward component is observed for all cometary ions. An asymmetry is found in the average cometary ion density in a solar wind electric field reference frame, with higher density in the negative (south) electric field hemisphere. There is no corresponding signature in the average magnetic field strength.

Propagation of electromagnetic waves in circular rods in torsion

1963 ◽  
Vol 255 (1059) ◽  
pp. 389-416 ◽  
Keyword(s):  
Magnetic Field ◽  
Magnetic Induction ◽  
Constitutive Equations ◽  
Electromagnetic Waves ◽  
Linear Functions ◽  
Static Deformation ◽  
Polynomial Functions ◽  
Electric And Magnetic Field ◽  
Speed Of Propagation ◽  
Propagation Of Waves

Invariance considerations are employed to write down constitutive equations governing the propagation of electromagnetic waves in isotropic materials with a centre of symmetry which are subject to a static deformation. It is assumed that the dielectric displacement and magnetic induction vectors are linear functions of the electric and magnetic field intensities, respectively, but are general polynomial functions in the quantities which specify the deformation. The theory is employed to examine propagation along circular cylindrical rods in torsion. Rotating waves are produced whose speed of propagation and rate of rotation depend upon the magnitude of the deformation and the properties of the material. The nature of these waves is examined for the general case where there is no restriction either upon the amount of torsion or upon the magnitude of the effect. When the amount of torsion, or the dependence of the effect upon deformation is small, solutions can be obtained based upon those for the propagation of waves in undeformed materials.

scholarly journals S-wave propagating in an anisotropic inhomogeneous elastic medium under the influence of gravity, initial stress, electric and magnetic field

2014 ◽  
Vol 41 (2) ◽  
pp. 141-157 ◽  
Author(s):  
Rajneesh Kakar ◽  
Shikha Kakar
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Initial Stress ◽  
Isotropic Medium ◽  
Shear Waves ◽  
S Wave ◽  
Incompressible Medium ◽  
Material Parameters ◽  
Electric And Magnetic Field ◽  
Inhomogeneous Elastic Medium

The purpose of this paper is to study the effect of gravity, initial stress, non-homogeneity, electric and magnetic field on the propagation of shear waves in an anisotropic incompressible medium. Various graphs are plotted to show the effect of direction of propagation, the anisotropy, magnetic field, electric field, non-homogeneity of the medium and the initial stress on shear waves. The dispersion equations for shear waves are obtained and discussed for different cases. In fact, in the absence of various material parameters, these equations are in agreement with the classical results for isotropic medium.

scholarly journals Spatial Averaging Schemes of In Situ Electric Field for Low-Frequency Magnetic Field Exposures

IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 184320-184331 ◽  
Author(s):  
Yinliang Diao ◽  
Jose Gomez-Tames ◽  
Essam A. Rashed ◽  
Robert Kavet ◽  
Akimasa Hirata
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Low Frequency ◽  
Spatial Averaging ◽  
Frequency Magnetic Field
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