scholarly journals ANALYSES OF RADIATION OF ELECTROMAGNETIC WAVES IN THE HIGH-VOLTAGE AIR DUCT (150 kV) CONSTRUCTION ON HEALTH

2017 ◽  
Vol 3 (4) ◽  
pp. 152-159
Author(s):  
Erwin Azizi Jayadipraja
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Wave ◽  
Field Strength ◽  
Electric Field ◽  
Magnetic Field Strength ◽  
High Voltage ◽  
Electromagnetic Waves ◽  
Wave Radiation ◽  
Strength Analysis ◽  
The Government

Background: High-voltage air ducts is the government program to supply electricity needs. However, in practice, obstacles have been identified in the form of rejection from the community due to the outstanding issues that high-voltage air ducts have an impact on health.Aim: This research aims to analysis the magnitude of electromagnetic wave radiation of high-voltage air ducts construction on health.Methods: The study was conducted by measuring electromagnetic wave radiation prior to high-voltage air ducts (150 kV) construction and predicting the amount of radiation generated after this operation and its impact on health.Result: The field measurement result showed that the highest strength of magnetic field in the absence of construction and operation activity of high-voltage air ducts 150 kV was 0.00085 mT and the highest electric field was 0.004241251 V/m. The results of the magnetic field strength analysis showed that the highest strength of magnetic field and electric field when the high-voltage air ducts is completed and operated was magnetic field of 0.00415 mT and electric field of 38.4 V/m. The value was far lower than the standard limits recommended by IRPA / INIRC, WHO1990 and SNI 04-6950-2003. The allowed electric field strength is 5 kV / m and the allowed magnetic field strength is 0.1 mT.Conclusion: Electromagnetic wave radiation of High-Voltage Air Ducts is not exceeded the allowed limit, so it will not cause a direct risk to health.

scholarly journals An experimental examination of the electrostatic behaviour of supraconductors.

1936 ◽  
Vol 155 (884) ◽  
pp. 102-110 ◽  
Author(s):  
Heinz London ◽  
Frederick Alexander Lindemann
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Electric Field ◽  
Magnetic Field Strength ◽  
Current Density ◽  
Experimental Examination ◽  
Characteristic Constant

In previous papers of F. and H. London supraconductivity has been described as a phenomenon, in which the current density is not connected with the electric field, as in normal conductors, but depends on magnetic field strength according to the equation Λ c curl J = - H with B = H and with Λ = m / ne 2, a new characteristic constant which contains the number n of supraconducting electrons. the behaviour of the electric field is not completely determined by this equation. Using Maxwell's induction law one can conclude from (1) only that Λ c curl j = c curl E or Λj = E + grand μ, where the physical signifance of grad μ is yet unknown.

A portable apparatus for measuring the magnetic field strength in an electromagnetic wave

1931 ◽  
Vol 27 (3) ◽  
pp. 481-489
Author(s):  
L. G. Vedy ◽  
A. F. Wilkins
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Wave ◽  
Magnetic Fields ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Special Means ◽  
Portable Apparatus ◽  
The Magnetic Field ◽  
Field Strengths

A portable apparatus is described which is capable of measuring directly, by means of a loop aerial, the magnetic field in an electromagnetic wave. Accurate measurements are possible of magnetic fields corresponding to field strengths of 0·2 millivolts per metre. Special means of providing small known calibrating E. M. F. S are described. The apparatus can be used to measure signals over the range 6 microvolts to 300 millivolts. Used in conjunction with a small portable vertical aerial, field strengths down to 2 microvolts per metre can be measured.

Enhanced Capture of Magnetic Microbeads Using Combination of Reduced Magnetic Field Strength and Sequentially Switched Electroosmotic Flow—A Numerical Study

2015 ◽  
Vol 137 (5) ◽  
Author(s):  
Debarun Das ◽  
Marwan F. Al-Rjoub ◽  
Rupak K. Banerjee
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Field Strength ◽  
Electric Field ◽  
Magnetic Field Strength ◽  
Electric Fields ◽  
Electroosmotic Flow ◽  
Separation Technique ◽  
Target Cells ◽  
Magnetic Microbeads

Magnetophoretic immunoassay is a widely used technique in lab-on-chip systems for detection and isolation of target cells, pathogens, and biomolecules. In this method, target pathogens (antigens) bind to specific antibodies coated on magnetic microbeads (mMBs) which are then separated using an external magnetic field for further analysis. Better capture of mMB is important for improving the sensitivity and performance of magnetophoretic assay. The objective of this study was to develop a numerical model of magnetophoretic separation in electroosmotic flow (EOF) using magnetic field generated by a miniaturized magnet and to evaluate the capture efficiency (CE) of the mMBs. A finite-volume solver was used to compute the trajectory of mMBs under the coupled effects of EOF and external magnetic field. The effect of steady and time varying (switching) electric fields (150–450 V/cm) on the CE was studied under reduced magnetic field strength. During switching, the electric potential at the inlet and outlet of the microchannel was reversed or switched, causing reversal in flow direction. The CE was a function of the momentum of the mMB in EOF and the applied magnetic field strength. By switching the electric field, CE increased from 75% (for steady electric field) to 95% for lower electric fields (150–200 V/cm) and from 35% to 47.5% for higher electric fields (400–450 V/cm). The CE was lower at higher EOF electric fields because the momentum of the mMB overcame the external magnetic force. Switching allowed improved CE due to the reversal and decrease in EOF velocity and increase in mMB residence time under the reduced magnetic field strength. These improvements in CE, particularly at higher electric fields, made sequential switching of EOF an efficient separation technique of mMBs for use in high throughput magnetophoretic immunoassay devices. The reduced size of the magnet, along with the efficient mMB separation technique of switching can lead to the development of portable device for detection of target cells, pathogens, and biomolecules.

Electromagnetic Scattering: The Mie Solution

2017 ◽  
Author(s):  
John A. Adam
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Electromagnetic Wave ◽  
Electric Field ◽  
Electromagnetic Scattering ◽  
Scattered Radiation ◽  
Electromagnetic Waves ◽  
Rayleigh Scattering ◽  
Electromagnetic Theory ◽  
Electromagnetic Energy

This chapter focuses on the mathematics underlying the scattering of electromagnetic waves. An electromagnetic wave is comprised of an electric field and a magnetic field, both of which are functions of time and space as the wave propagates. The direction of propagation and the directions of these fields form a mutually orthogonal triad. When an electromagnetic field encounters an electron bound to a molecule, the electron is accelerated by the electric field of the wave. An accelerated electron will also radiate electromagnetic energy in the form of waves in all directions (to some extent)—this is known as scattered radiation. The chapter first considers Maxwell's equations of electromagnetic theory before discussing the vector Helmholtz equation for electromagnetic waves, the Lorentz-Mie solution and its construction, the Rayleigh scattering limit, and the radiation field generated by a Hertzian dipole.

scholarly journals Isolated electrostatic structures observed throughout the Cluster orbit: relationship to magnetic field strength

2004 ◽  
Vol 22 (7) ◽  
pp. 2515-2523 ◽  
Author(s):  
J. S. Pickett ◽  
L.-J. Chen ◽  
S. W. Kahler ◽  
O. Santolík ◽  
D. A. Gurnett ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Electric Field ◽  
Magnetic Field Strength ◽  
Local Magnetic Field ◽  
Unexpected Result ◽  
Time Duration ◽  
Waveform Data ◽  
Negative Peak ◽  
The Magnetic Field

Abstract. Isolated electrostatic structures are observed throughout much of the 4RE by 19.6RE Cluster orbit. These structures are observed in the Wideband plasma wave instrument's waveform data as bipolar pulses (one positive and one negative peak in the electric field amplitude) and tripolar pulses (two positive and one negative peak, or vice versa). These structures are observed at all of the boundary layers, in the solar wind and magnetosheath, and along auroral field lines at 4.5-6.5RE. Using the Wideband waveform data from the various Cluster spacecraft we have carried out a survey of the amplitudes and time durations of these structures and how these quantities vary with the local magnetic field strength. Such a survey has not been carried out before, and it reveals certain characteristics of solitary structures in a finite magnetic field, a topic still inadequately addressed by theories. We find that there is a broad range of electric field amplitudes at any specific magnetic field strength, and there is a general trend for the electric field amplitudes to increase as the strength of the magnetic field increases over a range of 5 to 500nT. We provide a possible explanation for this trend that relates to the structures being Bernstein-Greene-Kruskal mode solitary waves. There is no corresponding dependence of the duration of the structures on the magnetic field strength, although a plot of these two quantities reveals the unexpected result that with the exception of the magnetosheath, all of the time durations for all of the other regions are comparable, whereas the magnetosheath time durations clearly are in a different category of much smaller time duration. We speculate that this implies that the structures are much smaller in size. The distinctly different pulse durations for the magnetosheath pulses indicate the possibility that the pulses are generated by a mechanism which is different from the mechanism operating in other regions.

scholarly journals GAMBARAN INDUKSI ELEKTROMAGNETIK BEBERAPA JENIS HANDPHONE YANG DIGUNAKAN MAHASISWA KEDOKTERAN ANGKATAN 2013

2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Rich V. Wowor
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Wave ◽  
Radiation Field ◽  
Electromagnetic Waves ◽  
Wave Radiation ◽  
Cross Sectional ◽  
Significant Difference ◽  
The Difference ◽  
Harmful Radiation ◽  
Post Hoc

Abstract: Mobile phone is a source of potentially harmful radiation. The form of signals in two radiation field, the near magnetic field and the remote magnetic field. This research is quantitative, with a cross-sectional approach. The results of the study, the highest standby electromagnetic waves is BlackBerry smartphone, while lowest  one is the Samsung. At the calling modes, highest is Blackberry and Nokia and the  lowest one is Samsung. At the receiving modes the biggest wave is Blackberry, lowest is Samsung. Based on the results of the ANOVA test it was found that there is a significant difference (p = 0.003, p <0.05) in the fourth electromagnetic waves smartphone brands when making a call. While in standby and receive calls no significant difference (p = 0.120 and p = 0.115, p> 0.05). Therefore, no difference statistically and required further analysis (post-hoc) to test the Least Significant Difference (LSD) or the Least Significance difference (LSD). There is a significant difference between the top of the electromagnetic wave smartphone brands Samsung, Nokia, and Blackberry at the time of call. While all four brands of smartphones is apparently the difference electromagnetic waves of the Samsung and Nokia with significant difference (p = 0.001), followed by the differences between the Samsung and Blackberry (p = 0.002). It can also take a look at the difference in the mean difference of the four brands of electromagnetic waves where the average difference between Nokia and Samsung is the smallest (-4.035), followed by the difference between the Samsung with Blackberry (-4.001). Keywords: handphone, electromagnetic wave, radiation field.   Abstrak: Handphone merupakan sumber radiasi potensial yang membahayakan. Signal telepon seluler yang dikirim membentuk dua buah lapangan radiasi yakni, medan magnet dekat dan medan magnet jauh. Penelitian ini bersifat kuantitatif, dengan pendekatan cross sectional. Hasil penelitian, smartphone saat standby tertinggi Blackberry, terendah Samsung. Saat panggilan tertinggi Blackberry dan Nokia, terendah Samsung. Saat menerima panggilan, terbesar adalah Blackberry, terendah Samsung. Berdasarkan hasil uji ANOVA terdapat perbedaan bermakna (p = 0,003; p<0,05) induksi elektromagnetik pada keempat merk smartphone saat melakukan panggilan. Sedangkan pada saat standby dan menerima panggilan tidak terdapat perbedaan yang bermakna (p = 0,120 dan p = 0,115; p > 0,05).  Oleh karena tidak terdapat perbedaan secara statistik maka diperlukan analisis lanjutan (post-hoc) dengan melakukan uji Beda Nyata Terkecil (BNT) atau Least Significance Diferrence (LSD). Terdapat perbedaan yang bermakna atas induksi elektromagnetik smartphone antara merk Samsung, Nokia, dan Blackberry pada saat melakukan panggilan. Sedangkan dari keempat merk smartphone tersebut ternyata perbedaan induksi elektromagnetik antara merk Samsung dan Nokia memiliki perbedaan yang paling signifikan (p = 0,001) kemudian diikuti oleh perbedaan antara merk Samsung dengan Blackberry (p = 0,002). Hal ini dapat juga kita lihat pada selisih perbedaan rerata dari keempat merk tersebut dimana selisih rerata induksi elektromagnetik antara merk Samsung dengan Nokia merupakan yang terkecil (-4,035) kemudian diikuti oleh selisih antara merk Samsung dengan Blackberry (-4,001). Kata kunci: Handphone, induksi elektromagnetik, lapangan radiasi.

scholarly journals MODELLING OF THE ELECTROMAGNETIC FIELDS CREATED BY COMPACT MULTI SEGMENT POWER LINES

2020 ◽  
Vol 2018 (1) ◽  
pp. 152-161 ◽  
Author(s):  
Natal'ya Buyakova ◽  
Vasiliy Zakaryukin ◽  
Andrey Kryukov ◽  
Van Le
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Electric Field ◽  
Magnetic Field Strength ◽  
Electromagnetic Fields ◽  
Power Line ◽  
Power Lines ◽  
Program Complex ◽  
Analysis Technique ◽  
Article Analysis

In the article analysis technique of electromagnetic safety conditions on routes of compact power lines (CPL) is offered. As the tool the program complex Fazonord was applied to modeling of CPL modes and electromagnetic fields. Results of modeling show that the average levels of CPL electric field strengths exceed a similar indicator for the standard power line by 25…145 %, distinctions of maximums lie within 7… 150 %. Especially considerable strength excesses take place at three-segment CPL. By criterion of magnetic field strength the return picture is observed: levels of CPL magnetic field strength on 70 … 90 % below than in traditional power line, and the best picture of electromagnetic safety possesses the foursegment power line.

scholarly journals Investigating the anatomy of magnetosheath jets – MMS observations

2018 ◽  
Vol 36 (2) ◽  
pp. 655-677 ◽  
Author(s):  
Tomas Karlsson ◽  
Ferdinand Plaschke ◽  
Heli Hietala ◽  
Martin Archer ◽  
Xóchitl Blanco-Cano ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Electromagnetic Waves ◽  
Dynamic Pressure ◽  
Lower Hybrid ◽  
Electrostatic Waves ◽  
Poynting Flux ◽  
Generation Mechanisms ◽  
Two Jets

Abstract. We use Magnetosphere Multiscale (MMS) mission data to investigate a small number of magnetosheath jets, which are localized and transient increases in dynamic pressure, typically due to a combined increase in plasma velocity and density. For two approximately hour-long intervals in November, 2015 we found six jets, which are of two distinct types. (a) Two of the jets are associated with the magnetic field discontinuities at the boundary between the quasi-parallel and quasi-perpendicular magnetosheath. Straddling the boundary, the leading part of these jets contains an ion population similar to the quasi-parallel magnetosheath, while the trailing part contains ion populations similar to the quasi-perpendicular magnetosheath. Both populations are, however, cooler than the surrounding ion populations. These two jets also have clear increases in plasma density and magnetic field strength, correlated with a velocity increase. (b) Three of the jets are found embedded within the quasi-parallel magnetosheath. They contain ion populations similar to the surrounding quasi-parallel magnetosheath, but with a lower temperature. Out of these three jets, two have a simple structure. For these two jets, the increases in density and magnetic field strength are correlated with the dynamic pressure increases. The other jet has a more complicated structure, and no clear correlations between density, magnetic field strength and dynamic pressure. This jet has likely interacted with the magnetosphere, and contains ions similar to the jets inside the quasi-parallel magnetosheath, but shows signs of adiabatic heating. All jets are associated with emissions of whistler, lower hybrid, and broadband electrostatic waves, as well as approximately 10 s period electromagnetic waves with a compressional component. The latter have a Poynting flux of up to 40 µW m−2 and may be energetically important for the evolution of the jets, depending on the wave excitation mechanism. Only one of the jets is likely to have modified the surrounding magnetic field into a stretched configuration, as has recently been reported in other studies. None of the jets are associated with clear signatures of either magnetic or thermal pressure gradient forces acting on them. The different properties of the two types also point to different generation mechanisms, which are discussed here. Their different properties and origins suggest that the two types of jets need to be separated in future statistical and simulation studies. Keywords. Magnetospheric physics (magnetosheath; plasma waves and instabilities; solar wind–magnetosphere interactions)

Das toroidale schwachionisierte Magnetoplasma II

1967 ◽  
Vol 22 (12) ◽  
pp. 1904-1919
Author(s):  
F. Karger
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Charge Carrier ◽  
Electric Field ◽  
Magnetic Field Strength ◽  
Positive Column ◽  
Substantial Reduction ◽  
Field Method ◽  
Critical Magnetic Field ◽  
Neutral Gas

A special alternating field method was used to eliminate the influence of the concentration effect (described in Part I1) on the measurements of interest and to increase by more than an order of magnitude the critical magnetic field strength for the onset of the helical instability of the positive column. This made it possible to check in detail the theory — formulated in Parts I and II — of a stable, weakly ionized toroidal magnetoplasma (potential profile, density profile, charge carrier losses).The theoretically predicted transverse electric field strength leading to the torus drift was observed, while the outward density displacement due to the torus drift did not occur. It was proved that the reason for this was an effect which results from a transverse gradient in the rate of ionization (grad ξ effect) and which causes a substantial reduction of the charge carrier losses. In the decaying plasma with vanishing longitudinal electric field, on the other hand, the outward density displacement was reeorded in accordance with the theory.The influence of the toroidal curvature on the magnetic field strength at which the helical instability sets in and on the turbulent state of the positive column was also investigated. It was also possible to verify the influence of the grad ξ effect on the helical oscillation.The grad ξ effect may be important for the early heating phase in projected toroidal fusion machines with neutral gas stabilization.

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