scholarly journals WHISTLING CHARACTERISTICS DURING PERIODS OF IONOSPHERIC DISTURBANCES

2019 ◽  
pp. 173-181
Author(s):  
Ю.М. Михайлов ◽  
О.В. Капустина ◽  
Г.И. Дружин
Keyword(s):  
Magnetic Field ◽  
Refractive Index ◽  
Electric Field ◽  
Electron Concentration ◽  
Concentration Gradient ◽  
Sharp Increase ◽  
Ionospheric Disturbances ◽  
Force Line ◽  
Atmospheric Discharges ◽  
Vlf Waves

Представлены результаты наблюдений активности свистов в обс. Карымшина (Камчатка) в период ноябрь-декабрь 2008 г. Этот период характеризовался превышением значений f0F2 и уменьшением hF2 по сравнению с обычным уровнем. Наиболее отчетливо этот эффект наблюдался в Иркутске, однако проявлялся и на Камчатке, хотя был выражен слабее. Такое событие объясняют 4 как изменением состава термосферы, так и возникновением западной составляющей электрического поля и градиента электронной концентрации в максимуме возмущений. Последнее также связывают с изменением направления северной компоненты межпланетного магнитного поля 4. В обычных условиях показатель преломления ОНЧ-волн в дневных условиях выше, чем в ночных 7, а число свистов, напротив, ночью выше, чем днем. 18-19 декабря на Камчатке наблюдалось появление свистящих атмосфериков (СА) днем в таком же количестве, как и ночью, порядка 10 1/мин. В то же время в периоды, следующие за максимумом изменения характеристик ионосферы (23, 24, 27, 29, 30 декабря), наблюдалось резкое возрастание количества свистов в дневное время до 50 1/мин. Возможно, что в данном случае источником свистов являлись атмосферные разряды, инициируемые в тайфуне, который наблюдались вблизи сопряженной области в южном полушарии. Увеличение числа свистов связано с изменением условий захвата на силовой линии L 2.4. The results of observations of whistlers in obs. Karymshina (Kamchatka) in the period November-December 2008 are presented. This period was characterized by an excess of f0F2 values and a decrease in hF2 compared to the usual level. This effect was most clearly observed in Irkutsk, however, it also manifested itself in Kamchatka, although it was less pronounced. Such an event is explained 4 by both a change in the composition of the thermosphere and the appearance of the western component of the electric field and the electron concentration gradient at the maximum of disturbances. The latter is also associated with a change in the direction of the northern component of the interplanetary magnetic field 4. Under normal conditions, the refractive index of VLF waves in daytime conditions is higher than at night 7, and the number of whistlers, on the contrary, is higher at night than during the day. On December 18-19, the appearance of whistling atmospherics in the daytime was observed in Kamchatka in the same amount as at night, about 10 1/min. At the same time, in the periods following the maximum changes in the ionosphere characteristics (23, 24, 27, 29, 30 December), there was a sharp increase in the number of whistles in the daytime to 50 1/min. It is possible that in this case the source of whistles were atmospheric discharges initiated in a typhoon, which were observed near the conjugate region in the southern hemisphere. The increase in the number of whistlers is associated with a change in the conditions of capture on the force line L 2.4.

Effects of Spin Orbit Interaction on Optical Properties for Quantum Dot and Quantum Wire

2017 ◽  
pp. 237-260
Author(s):  
Manoj Kumar ◽  
Pradip Kumar Jha ◽  
Aranya B. Bhattacherjee
Keyword(s):  
Magnetic Field ◽  
Refractive Index ◽  
Optical Absorption ◽  
Electric Field ◽  
Quantum Wire ◽  
Orbit Interaction ◽  
Spin Orbit ◽  
Spin Orbit Interaction ◽  
Rashba Spin ◽  
Index Changes

Here, the influence of external magnetic field on the optical absorption and refractive index changes for a parabolically confined quantum dot in the presence of Rashba spin orbit interaction have been investigated. The results are presented as a function of quantum confinement potential, magnetic field, Rashba spin orbit interaction strength and photon energy. Our results indicate the important influence of magnetic field on the peak positions of absorption coefficient and refractive index changes. For Quantum Wire, the energy dispersion relations are studied of the spin split subbands subjected to external transverse electric and magnetic fields in the presence of Rashba spin orbit interaction. For an infinite superlattice wire, it is found that the energy gaps between different subbands are shifted due to Rashba spin orbit interaction and external electric field. Here we have also investigated the influence of external electric field and magnetic field on the optical absorption of a parabolic confinement wire.

The theory of the cosmic background radio signal received within the ionosphere

1964 ◽  
Vol 277 (1370) ◽  
pp. 365-384 ◽  
Keyword(s):  
Magnetic Field ◽  
Refractive Index ◽  
Magnetic Fields ◽  
Electric Field ◽  
Free Space ◽  
Wave Theory ◽  
Ordinary Wave ◽  
Mean Square ◽  
Ray Theory ◽  
The Mean

The electric and magnetic fields to be expected within the ionosphere from a background source uniformly distributed across the sky are studied. The ray theory for an isotropic, horizontally stratified loss-free slowly varying ionosphere is first given, and it is shown that the mean-square moduli of the electric field components have n times their free-space value, and the mean-square moduli of the magnetic field components have n 3 times their free-space value where n is the local refractive index. The corrections to be expected when a full-wave theory is used are discussed. The ray theory for an anisotropic, loss-free ionosphere is then given and it is shown that the energy flux in a given direction is proportional to the Gaussian curvature at the associated point on the refractive index surface. For the ordinary wave, near the level of reflexion, the electric field is predominantly parallel to the earth’s magnetic field, and the small perpendicular component is nearly 100% circularly polarized. Results for the magnetic fields and for the fields of the extraordinary wave are also given and discussed.

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.

Effect of external magnetic field on lane formation in driven pair-ion plasmas

2021 ◽  
Vol 87 (2) ◽  
Author(s):  
Swati Baruah ◽  
U. Sarma ◽  
R. Ganesh
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Field Strength ◽  
Electric Field ◽  
Electric Field Strength ◽  
Coupling Parameter ◽  
Critical Parameters ◽  
Coulomb Coupling ◽  
Lane Formation ◽  
Parameter Values

Lane formation dynamics in externally driven pair-ion plasma (PIP) particles is studied in the presence of external magnetic field using Langevin dynamics (LD) simulation. The phase diagram obtained distinguishing the no-lane and lane states is systematically determined from a study of various Coulomb coupling parameter values. A peculiar lane formation-disintegration parameter space is identified; lane formation area extended to a wide range of Coulomb coupling parameter values is observed before disappearing to a mixed phase. The different phases are identified by calculating the order parameter. This and the critical parameters are calculated directly from LD simulation. The critical electric field strength value above which the lanes are formed distinctly is obtained, and it is observed that in the presence of the external magnetic field, the PIP system requires a higher value of the electric field strength to enter into the lane formation state than that in the absence of the magnetic field. We further find out the critical value of electric field frequency beyond which the system exhibits a transition back to the disordered state and this critical frequency is found as an increasing function of the electric field strength in the presence of an external magnetic field. The movement of the lanes is also observed in a direction perpendicular to that of the applied electric and magnetic field directions, which reveals the existence of the electric field drift in the system under study. We also use an oblique force field as the external driving force, both in the presence and absence of the external magnetic field. The application of this oblique force changes the orientation of the lane structures for different applied oblique angle values.

scholarly journals Double layers in the downward current region of the aurora

2003 ◽  
Vol 10 (1/2) ◽  
pp. 45-52 ◽  
Author(s):  
R. E. Ergun ◽  
L. Andersson ◽  
C. W. Carlson ◽  
D. L. Newman ◽  
M. V. Goldman
Keyword(s):  
Magnetic Field ◽  
Electron Beam ◽  
Phase Space ◽  
Electric Field ◽  
Electric Fields ◽  
Double Layers ◽  
Parallel Electric Field ◽  
Electrostatic Waves ◽  
Current Region ◽  
Decisive Evidence

Abstract. Direct observations of magnetic-field-aligned (parallel) electric fields in the downward current region of the aurora provide decisive evidence of naturally occurring double layers. We report measurements of parallel electric fields, electron fluxes and ion fluxes related to double layers that are responsible for particle acceleration. The observations suggest that parallel electric fields organize into a structure of three distinct, narrowly-confined regions along the magnetic field (B). In the "ramp" region, the measured parallel electric field forms a nearly-monotonic potential ramp that is localized to ~ 10 Debye lengths along B. The ramp is moving parallel to B at the ion acoustic speed (vs) and in the same direction as the accelerated electrons. On the high-potential side of the ramp, in the "beam" region, an unstable electron beam is seen for roughly another 10 Debye lengths along B. The electron beam is rapidly stabilized by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes. The "wave" region is physically separated from the ramp by the beam region. Numerical simulations reproduce a similar ramp structure, beam region, electrostatic turbulence region and plasma characteristics as seen in the observations. These results suggest that large double layers can account for the parallel electric field in the downward current region and that intense electrostatic turbulence rapidly stabilizes the accelerated electron distributions. These results also demonstrate that parallel electric fields are directly associated with the generation of large-amplitude electron phase-space holes and plasma waves.

Investigating flexible textile-based coils for wireless charging wearable electronics

2019 ◽  
Vol 50 (3) ◽  
pp. 333-345 ◽  
Author(s):  
Danmei Sun ◽  
Meixuan Chen ◽  
Symon Podilchak ◽  
Apostolos Georgiadis ◽  
Qassim S Abdullahi ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electrical Conductivity ◽  
Electromagnetic Field ◽  
Electric Field ◽  
Dimensional Stability ◽  
Screen Printing ◽  
Wearable Electronics ◽  
Wireless Charging ◽  
The Magnetic Field ◽  
Screen Printed

Smart and interactive textiles have been attracted great attention in recent years. This research explored three different techniques and processes in developing textile-based conductive coils that are able to embed in a garment layer. Coils made through embroidery and screen printing have good dimensional stability, although the resistance of screen printed coil is too high due to the low conductivity of the print ink. Laser cut coil provided the best electrical conductivity; however, the disadvantage of this method is that it is very difficult to keep the completed coil to the predetermined shape and dimension. The tested results show that an electromagnetic field has been generated between the textile-based conductive coil and an external coil that is directly powered by electricity. The magnetic field and electric field worked simultaneously to complete the wireless charging process.

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