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1

Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount  

Open Energy Info (EERE)

Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount St Helens, Washington Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount St Helens, Washington Details Activities (1) Areas (1) Regions (0) Abstract: A very low frequency (VLF) electromagnetic induction survey in the crater of Mount St. Helens has identified several electrically conductive structures that appear to be associated with thermal anomalies and ground water within the crater. The most interesting of these conductive structures lies beneath the central dome. It is probably a partial melt of dacite similar to that comprising the June 1981 lobe of the central dome. Author(s): James N. Towle

2

Cone structure and focusing of VLF and LF electromagnetic waves at high altitudes in the ionosphere  

SciTech Connect

The frequency and angle dependencies of the electric field radiated by an electric dipole E = E[sub 0] cos [omega]t are studied through numerical calculations of [vert bar]E[vert bar] in the VLF and LF frequency bands 0.02f[sub b] [le] F [le] 0.5f[sub b] in a model ionosphere over an altitude region of 800-6000 km where the wave frequency and electron gyrofrequency varies between F [approximately]4 - 500 kHz and f[sub b] [approx equal] (1.1 to 0.2) MHz respectively. It is found that the amplitudes of the electric field have large maxima in four regions: close to the direction of the Earth magnetic field line B[sub 0] (it is called the axis field E[sub 0]), in the Storey E[sub St], reversed Storey E[sub RevSt], and resonance E[sub Res] cones. The maximal values of E[sub 0], E[sub Res], and E[sub RevSt] are the most pronounced close to the lower hybrid frequency, F [approximately] F[sub L]. The flux of the electric field is concentrated in very narrow regions, with the apex angles of the cones [delta][beta] [approx equal] (0.1-1) deg. The enhancement and focusing of the electric field increases with altitude starting at Z>800 km. At Z [ge] 1000 up to 6000 km, the relative value of [vert bar]E[vert bar], in comparison with its value at Z = 800 km is about (10[sup 2] to 10[sup 4]) times larger. Thus, the flux of VLF and LF electromagnetic waves generated at high altitudes in the Earth's ionosphere are trapped into very narrow conical beams similar to laser beams. 7 refs., 14 figs., 5 tabs.

Alpert, Ya.L. (Harvard Smithsonian Center for Astrophysics, Cambridge, MA (United States)); Green, J.L. (NASA/Goddard Space Flight Center, Greenbelt, MD (United States))

1994-01-01T23:59:59.000Z

3

Investigation of electromagnetic welding  

E-Print Network (OSTI)

We propose several methodologies to study and optimize the electromagnetic process for Electromagnetic Forming (EMF) and Welding (EMW), thereby lowering the necessary process energy up to a factor of three and lengthening ...

Pressl, Daniel G. (Daniel Gerd)

2009-01-01T23:59:59.000Z

4

A BATSE investigation of radiation belt electrons precipitated by VLF waves. Final report  

SciTech Connect

The Compton Observatory commonly encounters fluxes of energetic electrons which have been scattered from the inner radiation belt to the path of the satellite by resonant interactions with VLF waves from powerful man-made transmitters. The present investigation was motivated by the fact that in the Fall of 1993, the Gamma Ray Observatory was boosted from a 650 km altitude circular orbit to a 750 km altitude circular orbit. This was an opportunity, for the first time, to make observations at two different altitudes using the same instrument. The authors have examined DISCLA data from the Burst & Transient Source Experiment (BATSE) experiment from 1 Sep. 1993 to 29 Jan. 1994. During the period of study they identified 48 instances of the satellite encountering a cloud of energetic electrons which had been scattered by VLF transmitters. They find that boosting the altitude of the circular orbit from 650 km to 750 km increased the intensity of cyclotron resonance scattered electrons by a factor of two. To search for long term changes in the cyclotron resonance precipitation, the authors have compared the approx. 750 km altitude data from 106 days at the end of 1993 with data at the same altitudes and time of year in 1991. The cyclotron resonance events in 1991 were three times more frequent and 25% of those cases were more intense than any seen in the 1993 data. They attribute this difference to increased level of geomagnetic activity in 1991 near the Solar Maximum.

Datlowe, D.W.

1995-04-01T23:59:59.000Z

5

Theoretical investigation of the coupling and propagation of ionospheric elf/vlf radiation into the earth-ionosphere waveguide  

SciTech Connect

This document describes a theoretical investigation of the propagation of extremely low frequency/very low frequency ELF/VLF, 1-5 kHz radiation from a source located in the D and lower E regions (60-85 km) of the ionosphere to a remote receiving site on the surface of the earth. It provides theoretical support for analyzing results of past experiments and planning future experiments to create an ELF/VLF communication system using high frequency heating modification of ionospheric currents. Analysis of the HF antenna array at the Arecibo Observatory determined that there was enough power in the sidelobes to modify the ionosphere, thereby creating an ELF/VLF source array. The ELF/VLF frequency response calculated for the ionospheric source array compared well with experimentally measured data. The coupling of radiation from ionospheric sources into the earth-ionosphere wave guide and the propagation of the radiation to receiving sites are investigated in detail using a model based on reciprocity.

Carroll, K.J.

1986-01-01T23:59:59.000Z

6

An investigation into the nonlinear frequency shift in magnetospherically propagated VLF pulses  

SciTech Connect

When ducted narrow-band VLF pulses pass through the Earth's magnetosphere, small frequency shifts of [approximately] 1 Hz may be observed at the receiving site on the ground. Such shifts may be due to Doppler effects, but nonlinear electron cyclotron resonance near the magnetospheric equator may also play a part. This paper is a study of nonlinear frequency shifts induced by wave-particle interaction effects. The development assumes strong nonlinearity and the dominance of particle trapping. The VLF pulses are considered to be much shorter than the scale length of the interaction region; however, for long pulses the results remain valid for the front part of the pulse as seen at the receiving site. Numerical simulations for the NAA and Siple transmitters are performed using a Vlasov code. The results are in general agreement with the theoretical analysis. Experimental observations are reviewed, and future active experiments are suggested.

Shklyar, D.R. (IZMIRAN, Troitsk (Russian Federation)); Nunn, D. (Univ. of Southampton (United Kingdom)); Smith, A.J. (British Antarctic Survey, Cambridge (United Kingdom)); Sazhin, S.S. (Univ. of Sheffield (United Kingdom))

1992-12-01T23:59:59.000Z

7

A BATSE investigation of radiation belt electrons precipitated by VLF waves. Final report, 2 May 1994-24 April 1995  

SciTech Connect

The Compton Observatory commonly encounters fluxes of energetic electrons which have been scattered from the inner radiation belt to the path of the satellite by resonant interactions with VLF waves from powerful man-made transmitters. The present investigation was motivated by the fact that in the Fall of 1993, the Gamma Ray Observatory was boosted from a 650 km altitude circular orbit to a 750 km altitude circular orbit. This was an opportunity, for the first time, to make observations at two different altitudes using the same instrument. The authors have examined DISCLA data from the Burst & Transient Source Experiment (BATSE) experiment from 1 Sep. 1993 to 29 Jan. 1994. During the period of study they identified 48 instances of the satellite encountering a cloud of energetic electrons which had been scattered by VLF transmitters. They find that boosting the altitude of the circular orbit from 650 km to 750 km increased the intensity of cyclotron resonance scattered electrons by a factor of two. To search for long term changes in the cyclotron resonance precipitation, the authors have compared the approx. 750 km altitude data from 106 days at the end of 1993 with data at the same altitudes and time of year in 1991. The cyclotron resonance events in 1991 were three times more frequent and 25% of those cases were more intense than any seen in the 1993 data. The authors attribute this difference to increased level of geomagnetic activity in 1991 near the Solar Maximum.

Datlowe, D.W.

1995-05-01T23:59:59.000Z

8

VLF Technique and Science in India  

Science Conference Proceedings (OSTI)

Since IGY period (1957-58), natural and artificially produced Very Low Frequency (VLF) electromagnetic radiations are being recorded at large number of ground stations and on board satellites to study various wave-plasma interactive phenomena. The terrestrial propagation of these VLF radio waves are primarily enabled through the earth ionosphere wave guide (EIWG) system to long horizontal distances around the globe and ducted along the geomagnetic field lines into the conjugate hemisphere through the ionosphere-plasmasphere-magnetosphere routes. The time frequency spectra indicate presence of dispersion and various cut-off frequencies providing several types of received signals like whistlers, chorus, tweeks, hiss, hisslers etc., which can be heard on an earphone with distinguishing audio structures. While the VLF technique has been a very effective tool for studying middle and high latitude phenomena, the importance of various anomalous characteristics over the Indian low latitude stations provide potentially new challenges for their scientific interpretation and modelling. The ducted and non-ducted propagation, low latitude TRIMPI/TLE effects, D-region ionisation perturbations due to solar and stellar x- and {gamma} ray emissions and detecting precursors of seismic activities are a few problems which will gain from low latitude studies. Since the conjugate points of Indian stations lie over the Indian oceanic region, the VLF propagation effects would be relatively noise free to observe rare and new phenomena requiring better SNR to detect such changes. The VLF signals emanating from the active seismic zones would require high sensitivity of the system and suitable network of transmitting and receiving stations. Results obtained on whistlers and related studies from a number of Indian stations covering geomagnetic latitude range between 13-24 deg. N are mentioned and reviewed in the background of theoretical understanding of the lightning return stroke signal elements, VLF propagation through cold plasma, ionospheric wave guide mode, electron precipitation due to cyclotron resonance and production of ionisation in the D-region due to solar/stellar UV/X/{gamma}-rays. Further use of the VLF technique in terms of improving both observational data for real time monitoring/modelling of geophysical phenomena and exploring space weather conditions are considered as part of a future Indian programme.

Chakravarty, S. C. [Member, Governing Body, Indian Centre for Space Physics, Kolkata (India)

2010-10-20T23:59:59.000Z

9

Ionospheric VLF waves and optical phenomena over active thunderstorms. [VLF (very low frequency)  

SciTech Connect

In 1987 and 1988, two campaigns, the Wave Induced Particle Precipitation campaign and the Thunderstorm II campaign, were conducted to investigate lightning-generated effects in the upper atmosphere and ionosphere. Two rockets and 6 balloons were launched near thunderstorms in these campaigns. Optical and electrical signals from hundreds of lightning strokes were recorded. The author has been able to study some problems about lightning-generated VLF waves in the ionosphere which have not been well investigated previously. This dissertation reports the following: (1) The downward-looking optical detector on the rocket recorded some anomalous characteristic optical phenomena. (2) The author studied the relation between the amplitude of lightning-generated VLF waves in the ionosphere and the lightning current recorded by the SUNYA lightning network. This study shows that the amplitude of waves at frequencies below 5 kHz has linear response to the lightning current. (3) The author has been able to determine the propagation path of the lightning-generated VLF waves from the source to the rocket. The path is consistent with the leaky waveguide hypothesis. (4) The amplitude of lightning-generated VLF waves has been found to have maxima and minima at different altitudes, instead of being attenuated monotonically with altitude as expected. A theoretical model has been proposed which shows that the wave amplitude profiles are the result of interference between waves from an aperture area below the rocket. (5) The author numerically calculated the absorption of VLF waves at the bottom of the ionosphere. The electron density gradient of the ionosphere was taken into account. The characteristics of the absorption, such as the frequency dependence, were investigated. The author deduced that significant heating of the ionosphere is caused by lightning-generated VLF waves.

Li, Y.Q.

1993-01-01T23:59:59.000Z

10

Mapping groundwater contamination using dc resistivity and VLF geophysical methods -- A case study  

SciTech Connect

Geophysical methods can be helpful in mapping areas of contaminated soil and groundwater. Electrical resistivity and very low-frequency electromagnetic induction (VLF) surveys were carried out at a site of shallow hydrocarbon contamination in Utah County, Utah. Previously installed monitoring wells facilitated analysis of water chemistry to enhance interpretation of the geophysical data. The electrical resistivity and VLF data correlate well, and vertical cross-sections and contour maps generated from these data helped map the contaminant plume, which was delineated as an area of high interpreted resistivities.

Benson, A.K.; Payne, K.L.; Stubben, M.A. [Brigham Young Univ., Provo, UT (United States). Dept. of Geology and Geophysics

1997-01-01T23:59:59.000Z

11

VLF and LF signatures of mesospheric/lower ionospheric response to lightning discharges  

SciTech Connect

New evidence is presented of disturbances of the electrical conductivity of the nighttime mesosphere and the lower ionosphere in association with lightning discharges. In addition to extensive documentation of the characteristics of a class of event heretofore referred to as early/fast VLF events [Inan et al.], this data reveal a new feature of these events, consisting of a postonset peak that typically lasts for 1-2 s. The authors also report the observation of short-duration VLF or LF perturbation, in which the amplitude of the subionospheric signal exhibits a sudden change within 20 ms of the causative lightning discharge, and recovers back to its original level in < 3 s. These short-duration events have characteristics similiar to the previously observed rapid onset, rapid decay VLF signatures [Dowden et al.]. Both the typical and rapidly recovering events are observed primarily when the causative lightning discharge is within {+-}50 km of the VLF or LF great circle propagation path, indicating that the scattering from the localized disturbance is highly collimated in the forward direction. The latter in turn implies that for the parameters in hand, the transverse extent of the disturbance must be at least {approximately} 100-150 km. The measured VLF signatures are compared with the predictions of a three-dimensional model of subionospheric VLF propogation and scattering in the presence of localized ionospheric disturbances produced by electromagnetic impulses and quasi-electrostatic (QE) fields produced by lightning discharges. The rapidly recovering or short-duration events are consistent with the heating of the ambient electrons by quasi-static electric fields, in cases when heating is not intense enough to exceed the attachment or ionization thresholds. When no significant electron density changes occur, the conductivity changes due to heating alone last only as long as the QE fields, typically less than a few seconds. 29 refs., 12 figs.

Inan, U.S.; Slingeland, A.; Pasko, V.P. [Stanford Univ., Stanford, CA (United States); Rodriguez, J.V. [Phillips Laboratory, Hanscom Air Force Base, MA (United States)

1996-03-01T23:59:59.000Z

12

Multi-dimensional electromagnetic modeling and inversion with application to near-surface earth investigations  

Science Conference Proceedings (OSTI)

Electrical conductivity of the earth provides information about porosity, water saturation, salinity, clay content, and organic matter that cannot be duplicated by other geophysical methods of investigation. However, there is a complex relationship between ... Keywords: Electrical conductivity, Electromagnetics, Geophysics, Inversion, Modeling

Louise Pellerin; Philip E. Wannamaker

2005-03-01T23:59:59.000Z

13

Perturbations of ionosphere-magnetosphere coupling by powerful VLF emissions from ground-based transmitters  

Science Conference Proceedings (OSTI)

The characteristics of the plasma-wave disturbances stimulated in the near-Earth plasma by powerful VLF radiation from ground-based transmitters are investigated. Radio communication VLF transmitters of about 1 MW in power are shown to produce artificial plasma-wave channels (density ducts) in the near-Earth space that originate in the lower ionosphere above the disturbing emission source and extend through the entire ionosphere and magnetosphere of the Earth along the magnetic field lines. Measurements with the onboard equipment of the DEMETER satellite have revealed that under the action of emission from the NWC transmitter, which is one of the most powerful VLF radio transmitters, the generation of quasi-electrostatic (plasma) waves is observed on most of the satellite trajectory along the disturbed magnetic flux tube. This may probably be indicative of stimulated emission of a magnetospheric maser.

Belov, A. S., E-mail: alexis-belov@yandex.ru; Markov, G. A.; Ryabov, A. O. [Lobachevsky Nizhni Novgorod State University (Russian Federation); Parrot, M. [Environment Physics and Chemistry Laboratory (France)

2012-12-15T23:59:59.000Z

14

VLF remote sensing of the auroral electrojet  

SciTech Connect

The authors present data taken to test the use of phase and amplitude variations in ground based VLF wave propogation measurements as a means of determining the location of the auroral electrojet. High-energy (> 300 keV) precipitating electrons at the edge of the electrojet can induce phase and amplitude variations in VLF waves propogating through that region of the atmosphere. The authors present measurements made in conjunction with conventional magnetometer measurements as a way to validate this technique. Satellite measurements of field-aligned currents were available for one night of observations.

Cummer, S.A.; Bell, T.F.; Inan, U.S. [Stanford Univ., Stanford, CA (United States)] Zanetti, L.J. [Johns Hopkins Univ., Laurel, MD (United States)

1996-03-01T23:59:59.000Z

15

Ionospheric modification with a VLF transmitter  

SciTech Connect

Detectable heating of the nighttime D region by a 28.5 kHz signal is observed in 16 out of 144 cases with events occurring under conditions of moderate to low D region electron densities as represented by the unperturbed VLF signal levels. Three dimensional modeling of the effects of NAU heating on a probe VLF signal predicts values in general agreement with observations and suggests that maximum effects should occur under tenuous D region conditions. 11 refs., 6 figs., 2 tabs.

Inan, U.S.; Rodriguez, J.V.; Lev-Tov, S.; Oh, J. (Stanford Univ., CA (United States))

1992-10-23T23:59:59.000Z

16

Investigation of an Electromagnetic Interference (EMI) Problem Involving Light-Emitting Diode Streetlights and an Amateur Radio Tran sceiver  

Science Conference Proceedings (OSTI)

Any type of electronic device is susceptible to energy from the electromagnetic environment. This technical update describes an investigation of electromagnetic interference (EMI) problems associated with amateur radio, distribution hardware, and streetlights at a customer's home in Camden, Tennessee. Because light-emitting diode (LED) streetlights were deemed the direct cause of the EMI problem, an investigational plan involving a two-level effort was customized to fit the situation. First, field observ...

2011-10-06T23:59:59.000Z

17

The use of subionospheric VLF/LF propagation for the study of lower ionospheric perturbations associated with earthquakes  

SciTech Connect

It is recently recognized that the ionosphere is very sensitive to seismic effects, and the detection of ionospheric perturbations associated with earthquakes (EQs), attracts a lot of attention as a very promising candidate for short-term EQ prediction. In this review we propose a possible use of VLF/LF (very low frequency (3-30 kHz)/low frequency (30-300 kHz)) radio sounding of seismo-ionospheric perturbations. We first present the first convincing evidence on the presence of ionospheric perturbations for the disastrous Kobe EQ in 1995. The significant shift in terminator times in the VLF/LF diurnal variation, is successfully interpreted in terms of lowering of the lower ionosphere prior to the EQ, which is the confirmation of seismo-ionospheric perturbations. In order to avoid the overlapping with my own previous reviews [1, 2], we try to present the latest results including the statistical evidence on the correlation between the VLF/LF propagation anomalies (ionospheric perturbations) and EQs (especially with large magnitude and with shallow depth), a case study on the Indonesia Sumatra EQ (wavelike structures in the VLF/LF data), medium-distance (6{approx}8 Mm) propagation anomalies, the fluctuation spectra of subionospheric VLF/LF data (atmospheric gravity waves effect, the effect of Earth's tides etc.), and the mechanism of lithosphere - atmosphere - ionosphere coupling. Finally, we indicate the present situation of this kind of VLF/LF activities going on in different parts of the globe and we suggest the importance of international collaboration in this seismo-electromagnetics study.

Hayakawa, M. [Advanced Wireless Communications Research Center and Research Station on Seismo Electromagnetics, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu Tokyo 182-8585 (Japan)

2010-10-20T23:59:59.000Z

18

ELF and VLF radiation from the polar electrojet antenna  

SciTech Connect

An approximate evaluation is made of the ELF/VLF dipole moment of the polar electrojet antenna established by ionospheric heating via the use of powerful HF waves amplitude modulated with frequencies in the ELF/VLF range. The theory of reciprocity is used to determine the magnitude of the ELF/VLF waveguide excitation produced by such a dipole immersed in the ionosphere. Propagation under a series of ionospheres ranging from quiet auroral nighttime to disturbed auroral daytime is considered. 32 references.

Barr, R.; Stubbe, P.

1984-07-01T23:59:59.000Z

19

VLF versus MF heating of the lower ionosphere  

SciTech Connect

The perturbation in the signal strength of a VLF transmitter by another transmitter heating the ionosphere on the great circle path to the receiver is calculated for two cases: The NAA-Palmer path heated by the VLF transmitter, NAU, and the Omega Norway-Skibotn path heated by the MF transmitter, heating, near Tromsoe. Comparison implies either that VLF heating is over 100 times more effective than MF heating in terms of the perturbation produced, per RF heating watt, in VLF propagation in the Earth-ionosphere wave-guide or that the observed effect at Palmer is fortuitous or spurious.

Dowden, R.L.; Adams, C.D.D. (Univ. of Otago, Dunedin (New Zealand))

1991-08-01T23:59:59.000Z

20

Whistler precursors on a VLF transmitter signal  

SciTech Connect

Whistler precursors are discrete emissions which are occasionally seen just before two-hop whistlers. Most theories of precursors assume they are triggered emissions and focus on creating a triggering signal with the proper time delay from the causative sferic. Whistler precursors have now been seen on a signal from the Siple VLF transmitter. Phase analysis shows that these precursors are caused by a rapid increase in growth activity, and not by a triggering signal.

Paschal, E.W. (Stanford Univ., CA (United States))

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

VLF heating of the lower ionosphere  

SciTech Connect

A controlled wave-injection experiment with a 28.5 kHz transmitter having a radiated power of 100 kW has revealed evidence of ionospheric heating by the VLF waves. Calculations indicate that the observed effect can be attributed to the absorption of wave energy in the lower ionosphere, which is estimated to result in a 30% enhancement in the collision frequency at 85 km. This process also represents a new means of direct coupling of lightning energy to the lower ionosphere.

Inan, U.S. (Stanford Univ., CA (USA))

1990-05-01T23:59:59.000Z

22

Impact of SPS heating on VLF, LF, and MF telecommunications systems ascertained by experimental means  

DOE Green Energy (OSTI)

The results of experiments undertaken to assess the potential impact of the operation of the Satellite Power System on the D and E regions of the ionosphere, and on telecommunication systems that are dependent upon the structure of the lower ionosphere are summarized. Using the high-power high-frequency transmitter facility located at Platteville, Colorado, power densities comparable to the Satellite Power System can be delivered to the heights of 70 to 100 km above the surface of the earth. Observations of the performance of telecommunication systems that operate in the VLF, LF, and MF portions of the spectrum have been investigated during times when the ionosphere was modified with SPS comparable power density and when it was not. The results obtained indicte that the SPS, as currently configured with a peak power density of 23 mW/cm/sup 2/, will not adversely impact upon the performance of VLF, LF, and MF telecommunication systems.

Rush, C.M.; Violette, E.J.; Espeland, R.H.; Carroll, J.C.; Allen, K.C.

1980-07-01T23:59:59.000Z

23

Excitation of guided ELF-VLF waves through modification of the F{sub 2} ionospheric layer by high-power radio waves  

SciTech Connect

The possibility of controlled excitation of ELF-VLF electromagnetic waves through modification of the F{sub 2} ionospheric layer by high-power high-frequency emission is demonstrated in a natural experiment by using the Sura midlatitude heating facility. The excited low-frequency waves can be used to explore the near-Earth space and stimulate the excitation of a magnetospheric maser.

Markov, G. A.; Belov, A. S.; Komrakov, G. P. [Lobachevsky State University (Russian Federation); Parrot, M. [Environmental Physics and Chemistry Laboratory (France)

2012-03-15T23:59:59.000Z

24

Ionospheric VLF waves and optical phenomena over active thunderstorms. Ph.D. Thesis  

SciTech Connect

In 1987 and 1988, two campaigns, the Wave Induced Particle Precipitation campaign and the Thunderstorm 2 campaign, were conducted to investigate lightning-generated effects in the upper atmosphere and ionosphere. Two rockets (apogees 420km and 330km) and 6 balloons (float altitudes 30km) were launched near thunderstorms in these campaigns. Optical and electric signals from hundreds of lightning strokes were recorded by both the rockets and balloons. Using the data obtained in these two campaigns, the author has been able to study some problems about lightning-generated VLF waves in the ionosphere which have not been well investigated previously. In this dissertation, the author reports the following: the downward-looking optical detector on the rocket recorded some anomalous characteristic optical phenomena which had not been reported previously. This study shows that they occurred above the balloon altitude (30km), and the results are interpreted in terms of discharges at high altitudes. The author studied the relation between the amplitude of lightning-generated VLF waves in the ionosphere and the lightning current recorded by the SUNYA lightning network. This study shows that the amplitude of waves at frequencies below 5 kHz has linear response to the lightning current. Above 5 kHz, there is not a significant linear correlation between the wave amplitude and the lightning current. The author has been able to determine the propagation path of the lightning-generated VLF waves from the source to the rocket. The path is consistent with the leaky waveguide hypothesis in which waves travel in the waveguide to the vicinity of the rockets, and then propagate vertically through the ionosphere. The author has found that the amplitude of lightning generated VLF waves have maxima and minima at different altitudes instead of being attenuated monotonically with altitude as expected.

Li, Y.Q.

1993-01-01T23:59:59.000Z

25

Applications of the VLF Induction Method For Studying Some Volcanic  

Open Energy Info (EERE)

the VLF Induction Method For Studying Some Volcanic the VLF Induction Method For Studying Some Volcanic Processes of Kilauea Volcano, Hawaii Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Applications Of The Vlf Induction Method For Studying Some Volcanic Processes Of Kilauea Volcano, Hawaii Details Activities (1) Areas (1) Regions (0) Abstract: The very low-frequency (VLF) induction method has found exceptional utility in studying various volcanic processes of Kilauea volcano, Hawaii because: (1) significant anomalies result exclusively from ionically conductive magma or still-hot intrusions (> 800°C) and the attendant electrolytically conductive hot groundwater; (2) basalt flows forming the bulk of Kilauea have very high resistivities at shallow depths that result in low geologic noise levels and relatively deep depths of

26

ISEE-1 observations in the magnetosphere of VLF emissions triggered by nonducted coherent VLF waves during VLF wave-injection experiments  

SciTech Connect

It is noted that recent data from the ISEE-1 spacecraft indicate that VLF emissions triggered by nonducted coherent VLF waves often possess spectral characteristics markedly different from those of emissions triggered by ducted waves. Emission triggering by nonducted waves is found to involve a strong path selectiveness. It is also established that emission triggering by nonducted waves can take place over a wide L-range and may involve inner radiation belt particles of energy up to 200 keV. It is concluded that the VLF emission generation process can occur under much more general conditions than previously believed on the basis of the results of ground-to-ground wave-injection experiments.

Bell, T.F.; Inan, U.S.

1981-01-01T23:59:59.000Z

27

Bias Elimination and Scatter in Lightning Location by the VLF Arrival Time Difference Technique  

Science Conference Proceedings (OSTI)

In the very low frequency (VLF) band lightning flashes are detectable at ranges of several thousand kilometers. Studies of experimental data show that if systematic biases were eliminated from the U.K. Meteorological Office's VLF arrival time ...

Anthony C. L. Lee

1990-10-01T23:59:59.000Z

28

An investigation of the usefulness of extremely low-frequency electromagnetic measurements for treaty verification  

SciTech Connect

From FY 1986 through FY 1988, we monitored extremely low-frequency (ELF) electromagnetic (EM) fields to determine whether these signals could be detected from underground nuclear explosions. Signals clearly related to underground tests were detected only when the ELF field sensors were located within 10 km of surface ground zero. Theoretical analysis, based on the results of these measurements, shows that the ELF impulse signals from underground nuclear tests are of longer duration than those from lightning sources and are, therefore, less efficient in exciting resonances in the earth-ionosphere cavity, even though the source strength for each may be the same. Thus, ELF signals from underground nuclear tests with yields of <150 kT are generally lower than the background signals caused by worldwide lightning activity. Our conclusion is that ELF monitoring probably will not be useful for detecting underground nuclear tests at distances >10 km from the tests. 16 refs., 24 figs., 3 tabs.

Sweeney, J.J.

1989-01-01T23:59:59.000Z

29

An investigation of the usefulness of extremely low-frequency electromagnetic measurements for treaty verification  

Science Conference Proceedings (OSTI)

From FY 1986 through FY 1988, we monitored extremely low-frequency (ELF) electromagnetic (EM) fields to determine whether these signals could be detected from underground nuclear explosions. Signals clearly related to underground tests were detected only when the ELF field sensors were located within 10 km of surface ground zero. Theoretical analysis, based on the results of these measurements, shows that the ELF impulse signals from underground nuclear tests are of longer duration than those from lightning sources and are, therefore, less efficient in exciting resonances in the earth-ionosphere cavity, even though the source strength for each may be the same. Thus, ELF signals from underground nuclear tests with yields of nuclear tests at distances >10 km from the tests. 16 refs., 24 figs., 3 tabs.

Sweeney, J.J.

1989-01-01T23:59:59.000Z

30

Investigations of the torque anomaly in an annular sector. II. Global calculations, electromagnetic case  

E-Print Network (OSTI)

Recently, it was suggested that there was some sort of breakdown of quantum field theory in the presence of boundaries, manifesting itself as a torque anomaly. In particular, Fulling et al. used the finite energy-momentum-stress tensor in the presence of a perfectly conducting wedge, calculated many years ago by Deutsch and Candelas, to compute the torque on one of the wedge boundaries, where the latter was cutoff by integrating the torque density down to minimum lower radius greater than zero. They observed that that torque is not equal to the negative derivative of the energy obtained by integrating the energy density down to the same minimum radius. This motivated a calculation of the torque and energy in an annular sector obtained by the intersection of the wedge with two coaxial cylinders. In a previous paper we showed that for the analogous scalar case, which also exhibited a torque anomaly in the absence of the cylindrical boundaries, the point-split regulated torque and energy indeed exhibit an anomaly, unless the point-splitting is along the axis direction. In any case, because of curvature divergences, no unambiguous finite part can be extracted. However, that ambiguity is linear in the wedge angle; if the condition is imposed that the linear term be removed, the resulting torque and energy is finite, and exhibits no anomaly. In this paper, we demonstrate the same phenomenon takes place for the electromagnetic field, so there is no torque anomaly present here either. This is a nontrivial generalization, since the anomaly found by Fulling et al. is linear for the Dirichlet scalar case, but nonlinear for the conducting electromagnetic case.

Kimball A. Milton; Prachi Parashar; E. K. Abalo; Fardin Kheirandish; Klaus Kirsten

2013-07-09T23:59:59.000Z

31

High voltage VLF testing of power cables  

SciTech Connect

This publication describes a laboratory test program conducted with the objective to develop a test that would replace the existing dc withstand test. The article describes the methodology used to establish the voltage duration and magnitude of VLF (0.1 Hz) high voltage field tests suitable for crosslinked polyethylene (XLPE) insulated power cable. The results show that the voltage breakdown of laboratory aged XLPE cable at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz cause very little damage to the cable, and that 0.1 Hz testing appears to be a satisfactory alternate to dc testing. Preliminary values are suggested for voltage magnitude and time duration of cable acceptance, maintenance and proof tests at 0.1 Hz for XLPE cable rated up to 35 kV. A program is underway to similarly evaluate samples of service-aged XLPE cable; as well as to demonstrate the use of the preliminary test values at typical utility installations.

Eager, G.S.; Katz, C.; Fryszczyn, B. [Cable Technology Labs., Inc., New Brunswick, NJ (United States); Densley, J. [Ontario Hydro, Toronto, Ontario (Canada); Bernstein, B.S. [EPRI, Washington, DC (United States)

1997-04-01T23:59:59.000Z

32

Effects of energetic particle events on VLF/LF propagation parameters/1989. Interim report. [VLF/LF (very low frequency/low frequency)  

SciTech Connect

This report is a summary of disturbance effects of three major energetic particle events (PCA's) on VLF/LF propagation parameters as observed by the Phillips Laboratory High Resolution Oblique VLF/LF Ionosounder located in northern Greenland. Disturbance effects on ionospheric reflectivity parameters, including deduced reflection heights and plane wave reflection coefficients, are presented along with riometer, magnetometer, and satellite particle detector data. VLF/LF propagation, Ionospheric disturbances, Polar cap absorption events, Oblique ionosounding.

Klemetti, W.I.; Rasmussen, J.E.; Kossey, P.A.

1992-12-04T23:59:59.000Z

33

Numerical investigation of the physical model of a high-power electromagnetic wave in a magnetically insulated transmission line  

SciTech Connect

An efficient numerical code for simulating the propagation of a high-power electromagnetic pulse in a vacuum transmission line is required to study the physical phenomena occurring in such a line, to analyze the operation of present-day megavolt generators at an {approx}10-TW power level, and to design such new devices. The main physical theoretical principles are presented, and the stability of flows in the near-threshold region at the boundary of the regime of magnetic self-insulation is investigated based on one-dimensional telegraph equations with electron losses. Numerical (difference) methods-specifically, a method of characteristics and a finite-difference scheme-are described and their properties and effectiveness are compared by analyzing the high-frequency modes.

Samokhin, A. A. [Troitsk Institute for Innovation and Fusion Research (Russian Federation)

2010-02-15T23:59:59.000Z

34

Deriving ionospheric system parameters from VLF transmitter signal analysis  

Science Conference Proceedings (OSTI)

The lower layers of the earths ionosphere are important for long range data transmission in the very low frequency range (VLF) and of general geophysical interest as X-ray and particle bursts of solar and other origin leave their fingerprints there. ... Keywords: ionosphere, optimization algorithms, signal processing, system parameter identification, wavelet and Fourier transforms

Ernst D. Schmitter

2008-07-01T23:59:59.000Z

35

Investigation of Electromagnetic Field Threat to Fuel Tank Wiring of a Transport Aircraft  

Science Conference Proceedings (OSTI)

National Transportation Safety Board investigators have questioned whether an electrical discharge in the Fuel Quantity Indication System (FQIS) may have initiated the TWA-800 center wing tank explosion. Because the FQIS was designed to be incapable ...

Ely Jay J.; Nguyen Truong X.; Dudley Kenneth L.; Scearce Stephen A.; Beck Fred B.; Deshpande Manohar D.; Cockrell C. R.

2000-03-01T23:59:59.000Z

36

Observations of the characteristics of propagation of VLF signals during meridian transits by Sco X-1  

SciTech Connect

The authors have conducted a series of studies of the VLF propagation characteristics during coordinated radio, optical, ultraviolet, and X-ray observations of the X-ray star Sco X-1. The observations were taken from 9-12 March 1989, a period when Sco X-1 was particularly active, and during a time of intense day-side solar activity. VLF sites were used to obtain phase and amplitude data from the VLF transmitter and from more remote transmitters. This paper gives preliminary results which compare the time-varying X-ray flux with the VLF phase data taken during the observation.

Beall, J.H.; Wood, K.S.; Kelly, F.J.

1990-05-03T23:59:59.000Z

37

VLF wave stimulation experiments in the magnetosphere from Siple Station, Antarctica  

SciTech Connect

The experimental methods used in the VLF stimulation experiments at the Siple Station, Antarctica, are described together with the results of observations and their interpretations. Consideration is given to the equipment employed in the experiments, with special attention to the Jupiter VLF transmitter, and to the methodology used to stimulate VLF signals. Data are presented on the following types of experiments: (1) single-frequency growth and triggering, (2) frequency ramp, (3) multifrequency, and (3) noise simulation. The possibilities for new controlled VLF wave injection experiments in the earth's magnetospheric plasma are discussed. 44 references.

Helliwell, R.A.

1988-08-01T23:59:59.000Z

38

Direction finding of half-gyrofrequency VLF emissions in the off-equatorial region of the magnetosphere and their generation and propagation  

SciTech Connect

The spectra of VLF/ELF emissions in the off-equatorial region in the outer magnetosphere are, on occasion, found to consist of upper and lower bands with a frequency gap between them. The wave normal directions of the upper band VLF emissions have been determined by means of wave distribution function analyses based first on the measurement of three magnetic field components only, and then with the additional use of an electric field component. It is found that the wave distribution functions are composed of two peaks whose central wave normal angles {theta} with respect to the magnetic field at a geomagnetic latitude of {approximately} 17{degree} are close to the local oblique resonance cone {theta}{sub res} but whose values of {theta} are always about 15{degree}-20{degree} less than {theta}{sub res} at a higher latitude of {approximately}26{degree}. This observed wave normal behavior is compared with the theoretical prediction from direct ray tracing studies using the hypothesis deduced from a previous investigation that the waves are generated at the equator with wave normals close to {theta}{sub res}. A combination of this comparison and inverse ray tracing in which the initial wave normal directions are those determined from the wave distribution analysis has yielded the results that the {theta} values of the upper band VLF emissions are very close to {theta}{sub res} at the equator and that the normalized frequency there, {Lambda}{sub eq}, is above 0.5. Hence the upper band VLF emissions are identified as being half-gyrofrequency VLF emissions generated in the vicinity of the magnetic equator, with their wave normals close to {theta}{sub res}. The characteristics of propagation between the equatorial source region and the observing positions have been investigated by direct ray tracing. The generation mechanism is also discussed.

Muto, H.; Hayakawa, M. (Nagoya Univ., Aichi (Japan)); Parrot, M.; Lefeuvre, F. (Centre National de la Recherche Scientifique, Orleans (France))

1987-07-01T23:59:59.000Z

39

Electromagnetic Compatibility & Telecommunications  

Science Conference Proceedings (OSTI)

Directory of Accredited Laboratories. Electromagnetic Compatibility & Telecommunications. The Electromagnetic Compatability ...

2013-11-08T23:59:59.000Z

40

Trapped electron losses by interactions with coherent VLF waves  

SciTech Connect

VLF whistler waves from lightning enter the magnetosphere and cause the precipitation of energetic trapped electrons by pitch angle scattering. These events, known as Lightning-induced Electron Precipitation (LEP) have been detected by satellite and rocket instruments and by perturbations of VLF waves traveling in the earth-ionosphere waveguide. Detailed comparison of precipitating electron energy spectra and time dependence are in general agreement with calculations of trapped electron interactions with ducted whistler waves. In particular the temporal structure of the precipitation and the dynamic energy spectra of the electrons confirm this interpretation of the phenomena. There are discrepancies between observed and measured electron flux intensities and pitch angle distributions, but these quantities are sensitive to unknown wave intensities and trapped particle fluxes near the loss cone angle. The overall effect of lightning generated VLF waves on the lifetime of trapped electrons is still uncertain. The flux of electrons deflected into the bounce loss cone by a discrete whistler wave has been measured in a few cases. However, the area of the precipitation region is not known, and thus the total number of electrons lost in an LEP event can only be estimated. While the LEP events are dramatic, more important effects on trapped electrons may arise from the small but numerous deflections which increase the pitch angle diffusion rate of the electron population. {copyright} {ital 1996 American Institute of Physics.}

Walt, M.; Inan, U.S. [Space, Telecommunications and Radioscience Laboratory, Stanford University, Stanford, California (United States); Voss, H.D. [Lockheed Missiles and Space Co. (United States)

1996-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Outer zone electron precipitation produced by a VLF transmitter  

SciTech Connect

By means of high-resolution pitch angle measurements made by a magnetic-focusing electron spectrometer on the S3-3 satellite while in the drift loss cone region of the magnetosphere, characteristics of fluxes of 108- to 654-keV electron precipitated in the inner zone, in the slot region, and in the outer zone of the magnetosphere are all shown to be consistent with the precipitation's having been produced by the same ground-based VLF transmitter, UMS. Pitch angle measurements are used to locate the longitude of precipitation. The temporal pattern of transmitter operation obtained from synoptic data from a ground-based VLF receiver is used along with drift rate calculations to predict the electron energies as a function of L shell which should be observable by the S3-3 instrument. The predicted energy response is then compared with the in situ observations, getting complete agreement. Finally, wave-particle resonance calculations are made for each of the three regions. The study indicates that ground-based VLF transmitters, which have previously been shown to produce precipitation in the inner zone and slot regions, are almost certainly instrumental in precipitating electrons in the outer zone also. copyright American Geophysical Union 1988

Vampola, A.L.; Adams, C.D.

1988-03-01T23:59:59.000Z

42

VLF heating of the lower ionosphere: Variation with magnetic latitude and electron density profile  

SciTech Connect

The authors report the results of calculations of ionospheric absorption of VLF heating radiation, in comparison with HF heating. This work was motivated by recent observations of the effects of VLF heating, which indicate that it is much more efficient than HF heating, at least for certain ionospheric conditions. The authors assume an ionospheric model which is consistent with that observed during the previous heating experiments. Their results are in basic agreement with the experimental observations. They find that the enhancement in efficiency of VLF heating over HF heating is a feature of low latitudes, where ionospheric density profiles favor this effect. In the polar regions, HF heating is more efficient.

Barr, R. (National Institute of Water and Atmospheric Research Ltd., Lower Hutt (New Zealand)); Stubbe, P. (Max Planck Institut fuer Aeronomie, Katlenburg-Lindau (Germany))

1992-09-04T23:59:59.000Z

43

Recovery signatures of lightning-associated VLF perturbations as a measure of the lower ionosphere  

SciTech Connect

A new model of the physical processes associated with subionospheric VLF signal perturbations caused by lightning-induced electron precipitation (LEP) bursts is developed to diagnose the state of the lower ionosphere (e.g., electron number density and rate coefficients for various chemical reactions) on the basis of measurements of VLF recovery signatures. The model accounts for the energy spectrum of the electron bursts precipitated by lightning-generated whistlers, the chemical relaxation of enhanced secondary ionization in the nightime D region due to LEP bursts, and quantitatively treats the resultant effects on propagation of the VLF signal in the Earth-ionosphere waveguide. Application of the model to experimental data obtained for the VLF propagation path from NPM station (Hawaii) to Palmer station (Antarctica) indicates that effective electron detachment rate {gamma}, enhanced secondary ionization profile (e.g., energy content of LEP bursts), as well as the ambient electron density distribution, may be estimated using observed subionospheric VLF recovery signatures. The effective detachment rate was identified as {approximately}10{sup 18} N s{sup {minus}1}, where N is total number density of neutrals. Model indicates in particular that the attachment-detachment processes play the dominant role in recovery of subionospheric VLF signal perturbations on timescales {approximately}100 s, and that the observed perturbations of the NPM-Palmer signal correspond to the LEP bursts consisting of relatively soft (< 250 keV) electrons. 33 refs., 24 figs.

Pasko, V.P.; Inan, U.S. [Stanford Univ., CA (United States)

1994-09-01T23:59:59.000Z

44

Generation of ELF and VLF waves by HF-modulated polar electrojet via a thermal instability process  

SciTech Connect

Generation of ELF and VLF waves via a thermal instability process in a HF-modulated polar electrojet has been investigated. It is shown that a positive feedback through the electron-neutral collisional heating process can cause the transient response of the plasma to the modulated HF heater to grow exponentially. The threshold fields of the instability under normal electrojet conditions are found to be about 2.25 V/m and 1.13 V/m for the operation of the o-mode and x-mode heaters with a 50% duty cycle, respectively. For a heater wave field of, e.g., 1.5 V/m, the instability can be excited by the x-mode heater within a few tens of millisecond. The predicted dependence of the ELF/VLF radiation amplitude on the percentage of the duty cycle of the HF modulation is identical to that of the recent observational results of Barr and Stubbe. 28 refs., 2 figs.

Kuo, S.P. (Polytechnic Univ., Farmingdale, NY (United States)); Lee, M.C. (Massachusetts Inst. of Technology, Cambridge (United States))

1993-02-05T23:59:59.000Z

45

ELECTROMAGNETIC PUMP  

DOE Patents (OSTI)

This patent reiates to electromagnetic pumps for electricity-conducting fluids and, in particular, describes several modifications for a linear conduction type electromagnetic interaction pump. The invention resides in passing the return conductor for the current traversing the fiuid in the duct back through the gap in the iron circuit of the pump. Both the maximum allowable pressure and the efficiency of a linear conduction electromagnetic pump are increased by incorporation of the present invention.

Pulley, O.O.

1954-08-17T23:59:59.000Z

46

DE 1 VLF observations during Activny wave injection  

SciTech Connect

The authors report on coordinated high-altitude satellite observations in support of one of the first space-based VLF wave injection experiments, namely the USSR Aktivny mission. The Activny satellite (A) was designed to carry a VLF transmitter (nominal frequency {approximately}10 kHz, transmitter power {approximately}10 kW) coupled to a 20-m-diameter loop antenna in a nearly polar orbit (83 inclination, apogee {approximately}2500 km, perigee {approximately}500 km). The authors focus their attention on conjunction experiments between the Activny and DE 1 satellites. Because of problems in the deployment of the loop antenna, the radiated power capability of the antenna was significantly reduced. Although this substantially reduced the expectation of receiving detectable signal levels on the satellite, the DE 1/Activny conjunction experiments were nevertheless carried out as a means of possibly placing an upper limit on the radiated power. During the period November 1989 through April 1990, a total of 10 DE 1/Activny wave injection sessions were conducted. During each session the Activny transmitter operated at 10.537 kHz with 1 s On-1 s Off format, for a period of 6 min centered around the conjunction time. Though no Activny signals were detected by the LWR on the DE 1 satellite, the experimental constraints allow the authors to place an upper limit on the total power radiated by the Activny transmitter in the whistler-mode. Using experimental parameters, and the minimum detectable signal level of 0.05 {mu}V/m for LWR, they find the upper limit on the total power radiated by the Activny satellite in the whistler-mode to be {approximately}10 mW. Several recommendations for future space-based wave injection experiments are presented. 25 refs., 12 figs., 3 tabs.

Sonwalkar, V.S.; Inan, U.S.; Bell, T.F. [Stanford Univ., CA (United States)] [and others

1994-04-01T23:59:59.000Z

47

Antenna vector impedance measurement by the EXOS-D (AKEBONO) very low frequency plasma waves instrument (VLF)  

SciTech Connect

Antenna impedance has been measured on board the EXOS-D (Akebono) satellite by imposing a constant current at VLF. The impedance is obtained in a complex form, i.e., as a resistance and a capacitance. This is essential to obtain the absolute electric field intensities of the VLF waves. A critical frequency below which the resistive part becomes important is also obtained.

Hashimoto, Kozo (Tokyo Denki Univ. (Japan)); Nagano, Isamu (Kanazawa Univ. (Japan)); Okada, Toshimi (Toyama Prefectural Univ. (Japan)); Yamamoto, Masayuki; Kimura, Iwane (Kyoto Univ. (Japan))

1991-02-01T23:59:59.000Z

48

Propagation of beam-driven VLF waves from the ionosphere toward the ground  

SciTech Connect

As part of the Cooperative High Altitude Rocket Gun Experiment (CHARGE-2B) rocket mission, an electron beam was injected into the ionosphere with a modulated beam current in an effort to generate very low frequency (VLF) waves. The propagation of the beam-driven VLF waves through the ionosphere is examined here to determine whether it is possible to detect these wave emissions with ground receivers. The paths of the VLF waves from where they were generated near the rocket were followed to the bottom of the ionosphere and the decrease in wave amplitude due to wave-particle resonance and collisional damping was calculated. It was found that due to collisional damping, which for these VLF waves becomes large at altitudes below about 150 km, wave amplitudes were decreased below the background atmospheric noise level. A number of different beam injection events have been examined and in all of the cases studied the waves were sufficiently damped such that detection on the ground would not be possible. This is in agreement with observations on the ground in which no wave emissions were observed during the CHARGE-2B mission. Control parameters that would be more favorable for beam-generated VLF propagation to the ground are discussed for future experiments of this type. 23 refs., 8 figs., 1 tab.

Schriver, D.; Sotnikov, V.I.; Ashour-Abdalla, M. [Univ. of California, Los Angeles, CA (United States)] [and others

1995-03-01T23:59:59.000Z

49

Results of VLF campaigns in Summer, Winter and during Solar Eclipse in Indian Subcontinent and Beyond  

SciTech Connect

VLF propagation effects are generally understood in terms of the earth-ionosphere waveguide. However, details of the theory are still incomplete. Particularly important are the newly emerging fields of VLF Astronomy where the ionosphere is treated as a giant detector for extraterrestrial energetic phenomena and the subject of lithosphere-ionosphere coupling where the the disturbances of this giant detector is influenced by terrestrial events, especially earthquakes and other seismic activities. We review the activities of our group in these fields. In particular, we concentrate on the results of the VLF campaigns we conducted using over a dozen receiving stations in Summer, in Winter and during the Total Solar eclipse in July, 2009. We also discuss briefly the results we obtained in Antarctica and their implications.

Chakrabarti, Sandip K. [S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata (India); Indian Centre for Space Physics, 43 Chalantika, Garia Station Rd., Kolkata 700084 (India); Sasmal, S.; Mondal, S. K. [Indian Centre for Space Physics, 43 Chalantika, Garia Station Rd., Kolkata 700084 (India); Pal, S. [S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata (India)

2010-10-20T23:59:59.000Z

50

Computation of VLF response over half-plane and wedge models  

SciTech Connect

A theoretical solution is presented to the problem where a VLF anomaly is generated by a conducting half-plane or a perfectly conducting wedge below a stratified overburden. The solution is obtained by the use of a scattering matrix for plane-wave eigenfunctions. VLF anomalies have been computed for different values of the conductance and dip of the halfplane. The phase of the VLF anomaly due to a conducting half-plane depends on the conductance and the distance to the half-plane. Close to the half-plane the tilt angle and ellipticity are of opposite sign for a perfect conductor, but the ellipticity will change sign for a poor conductor. The VLF anomaly for a perfectly conducting wedge is essentially determined by the position of the upper surface of the wedge, i.e. the anomaly will closely resemble the anomaly of a perfectly conducting half-plane in the same position as the upper surface of the wedge.

Olsson, O.

1983-02-01T23:59:59.000Z

51

An Operational System for the Remote Location of Lightning Flashes Using a VLF Arrival Time Difference Technique  

Science Conference Proceedings (OSTI)

An operational system for the remote location of lightning flashes at ranges of thousands of kilometers is presented. The vertical electric fields of VLF radio atmospherics (sferics), together with time data, are observed at a network of just ...

Anthony C. L. Lee

1986-12-01T23:59:59.000Z

52

Effective recombination coefficient and solar zenith angle effects on low-latitude D-region ionosphere evaluated from VLF signal amplitude and its time delay during X-ray solar flares  

E-Print Network (OSTI)

Excess solar X-ray radiation during solar flares causes an enhancement of ionization in the ionospheric D-region and hence affects sub-ionospherically propagating VLF signal amplitude and phase. In first part of the work, using the well known LWPC technique, we simulated the flare induced excess lower ionospheric electron density by amplitude perturbation method. Unperturbed D-region electron density is also obtained from simulation and compared with IRI-model results. Using these simulation results and time delay as key parameters, we calculate the effective electron recombination coefficient ($\\alpha_{eff}$) at solar flare peak region. Our results match with the same obtained by other established models. In the second part, we dealt with the solar zenith angle effect on D-region during flares. We relate this VLF data with the solar X-ray data. We find that the peak of the VLF amplitude occurs later than the time of the X-ray peak for each flare. We investigate this so-called time delay ($\\bigtriangleup t$)....

Basak, Tamal

2013-01-01T23:59:59.000Z

53

Electromagnetic Leptogenesis  

E-Print Network (OSTI)

We present a new leptogenesis scenario, where the lepton asymmetry is generated by CP violating decays of heavy electroweak singlet neutrinos via electromagnetic dipole moment couplings to the ordinary light neutrinos. Akin to the usual scenario where the decays are mediated through Yukawa interactions, we have shown, by explicit calculations, that the desired asymmetry can be produced through the interference of the corresponding tree-level and one-loop decay amplitudes involving the effective dipole moment operators. We also find that the relationship of the leptogenesis scale to the light neutrino masses is similar to that for the standard Yukawa-mediated mechanism.

Bell, Nicole F; Law, Sandy S C

2008-01-01T23:59:59.000Z

54

Electromagnetic Leptogenesis  

E-Print Network (OSTI)

We present a new leptogenesis scenario, where the lepton asymmetry is generated by CP violating decays of heavy electroweak singlet neutrinos via electromagnetic dipole moment couplings to the ordinary light neutrinos. Akin to the usual scenario where the decays are mediated through Yukawa interactions, we have shown, by explicit calculations, that the desired asymmetry can be produced through the interference of the corresponding tree-level and one-loop decay amplitudes involving the effective dipole moment operators. We also find that the relationship of the leptogenesis scale to the light neutrino masses is similar to that for the standard Yukawa-mediated mechanism.

Nicole F. Bell; Boris J. Kayser; Sandy S. C. Law

2008-06-20T23:59:59.000Z

55

kappa. vector measurements of VLF signals by the satellite EXOS-D  

SciTech Connect

On board the EXOS-D (Akebono) satellite is a five channel PFX subsystem of VLF instruments, working to determine the wave normal of {kappa} vector and Poynting vector directions by measuring two components of E and three components of B fields using wire and loop antennas. In order to confirm the characteristics or capability of determining the {kappa} vector and the Poynting vector of a coherent VLF Omega signal transmitted from Australia have been analyzed. The observed Omega signal has been found to be right-handed polarized with Poynting vector is making a small angle with the geomagnetic field and lies nearly on the plane constructed by the geomagnetic field and {kappa} vector. The refractive index deduced from the E and B fields well agrees with that calculated by Appleton Hartree formula.

Yamamoto, Masayuki; Ito, Yoshihiko; Kishi, Yoji; Sawada, Akira; Kimura, Iwane (Kyoto Univ. (Japan)); Nagano, Isamu; Kennai, Eiichi (Kanazawa Univ. (Japan)); Okada, Toshimi (Toyama Prefectural Univ. (Japan)); Hashimoto, Kozo (Tokyo Denki Univ. (Japan))

1991-02-01T23:59:59.000Z

56

Modification of the lower ionosphere in lighting-induced electron precipitation events and through VLF heating  

SciTech Connect

Different mechanisms by which VLF waves from ground-based sources modify the nighttime lower ionosphere (D-region) are discussed. One process by which the ionosphere is regularly disturbed involves the precipitation of short (<2s) bursts of energetic (>40 keV) electrons out of the radiation belts in gyroresonant interactions with whistler waves launched by lightning discharges. A second process involves direct upward coupling of lightning electric fields to the lower ionosphere leading to intense electric fields and ionization enhancements. A third process is the heating of the lower ionosphere by upgoing VLF waves from ground-based transmitters and lightning, leading to up to 100% increase in electron temperature at 80-90 km altitudes 1.

Inan, U.S.

1990-10-01T23:59:59.000Z

57

Studies of VLF radio waves for sudden ionospheric disturbances (SID) in Kashmir region  

SciTech Connect

It is recognized that the ionosphere may be sensitive to seismic effects, and the detection of ionospheric perturbations associated with seismicity would be useful for short term prediction of seismic events. To observe this effect, Indian Centre for Space Physics has installed an antenna and receiver system at Kashmir University to monitor the variation of the VLF signal transmitted from VTX. We present the preliminary results from this station.

Wani, M. R.; Iqbal, Naseer [Department of Physics, University of Kashmir, Srinagar (India); Sasmal, Sudipta [Indian Centre for Space Physics, Kolkata (India)

2010-10-20T23:59:59.000Z

58

Signature of burst particle precipitation on VLF signals propagating in the Antarctic earth-ionosphere waveguide  

SciTech Connect

The burst precipitation of energetic electrons ({ge} 40 keV), induced by interactions with lightning-generated whistler mode waves, has been observed to cause phase and amplitude perturbations on subionospheric VLF signals (Trimpi events). With a knowledge of the propagation characteristics of the subionospheric signal, analysis of the perturbation details can lead to estimates of the energy, extent, and location of the precipitation. Trimpi events have been observed on VLF signals propagating at high latitudes (L {ge} 4) over Antarctica, on 3.79-kHz signals as they propagate from Siple toward VLF receivers at Halley and South Pole stations. To simulate the effects of precipitation, localized depressions in the ionospheric reflection height are introduced over the great circle propagation paths in the model, and it is seen that, while the amplitude (up to 6 dB) Trimpi events at Halley cannot be reproduced. Calculations are presented which show that signals echoing from precipitation patches located away from the great circle path could be the cause of such signatures.

Cotton, P.D. (Univ. of Sheffield (United Kingdom)); Smith, A.J. (Natural Environment Research Council, Cambridge (United Kingdom))

1991-11-01T23:59:59.000Z

59

Outer-zone electron precipitation produced by a vlf transmitter. Technical report  

SciTech Connect

Using high-resolution pitch-angle measurements made by a magnetic-focusing electron spectrometer on the S3-3 satellite while in the drift-loss-cone region of the magnetosphere, characteristics of fluxes of 108 to 654-keV electrons precipitated in the inner zone, in the slot region, and in the outer zone of the magnetosphere are all shown to be consistent with the precipitation having been produced by the same ground-based VLF transmitter, UMS. Pitch angle measurements are used to locate the longitude of precipitation. The temporal pattern of transmitter operation obtained from synoptic data from a ground-based VLF receiver is used along with drift-rate calculations to predict the electron energies as a function of L-shell which should be observable by the S3-3 instrument. The predicted energy response is then compared with the in-situ observations, getting complete agreement. Finally, wave-particle resonance calculations are made for each of the three regions. The study indicates that ground-based VLF transmitters, which have previously been shown to produce precipitation in the inner zone and slot regions, are almost certainly instrumental in precipitating electrons in the outer zone also.

Vampola, A.L.; Adams, C.D.

1988-03-01T23:59:59.000Z

60

NVLAP Electromagnetic Compatibility & Telecommunications ...  

Science Conference Proceedings (OSTI)

Electromagnetic Compatibility & Telecommunications LAP. Welcome. This site has been established for new applicants ...

2013-07-30T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Excitation of sidebands due to nonlinear coupling between a VLF transmitter signal and a natural ELF emission  

SciTech Connect

Symmetric sidebands are observed in the ionosphere by the AUREOL 3 satellite when it passes at a height of 1,200 km above the VLF transmitter at the Komsomolsk-on-Amur Alpha station (50{degree}5 N, 135{degree} E, frequency 11.90 and 12.65 kHz). The sidebands are about 500 Hz off the carrier frequency of Alpha pulses. They are approximately 20 dB lower than the transmitter signal, and they appear only when ELF natural emission above the local proton gyrofrequency is observed. The data are presented and analyzed. The nonlinear coupling of the VLF transmitter signal to natural ELF emission is invoked to explain the symmetric sidebands. It is shown that the nonlinear current excited by the beats of VLF and ELF waves is strong enough to explain the sideband amplitude.

Sotnikov, V.I.; Fiala, V.; Lefeuvre, F.; Lagoutte, D. (Lab. de Physique et Chimie de l'Environnement, Orleans (France)); Mogilevsky, M. (Space Research Inst., Moscow (USSR))

1991-07-01T23:59:59.000Z

62

Coincident bursts of auroral kilometric radiation and VLF emissions associated with a type III solar radio noise event  

SciTech Connect

This paper examines an isolated magnetospheric VLF/radio noise event that is highly suggestive of the triggering of terrestrial auroral kilometric radiation (AKR) by solar type III radio emission and of a close relation between AKR and broadband hiss. The solar type III burst was measured on polar HF riometers and was coincident with local dayside VLF/LF noise emission bursts at South Pole station. It was also coincident with AKR bursts detected on the AMPTE/IRM satellite, at the same magnetic local time as South Pole. On the basis of the close association of AKR and VLF bursts, and from geometrical considerations relating to wave propagnation, it is likely that the AKR source was on the dayside and on field lines near South Pole station. The general level of geomagnetic activity was very low. However, an isolated magnetic impulse event (MIE) accompanied by a riometer absorption pulse was in progress when all of the VLF/radio noise bursts occurred. The very close association of the type III burst at HF with the AKR is consistent with external stimulation of the AKR, if a different, more immediate, triggering process than that implied by Calvert is invoked. It is suggested here that some of the HF solar radiant energy may decay into waves with frequencies comparable to those of the AKR by parametric excitation or some other process, thus providing the few background photons required for the generation of AKR by the Wu and Lee cyclotron maser instability. The AKR, perhaps by modifying the magnetospheric electron velocity distribution, might have produced the observed VLF emissions. Alternatively, the VLF emissions may have arisen from the same anisotropic and unstable electron distribution function responsible for the AKR. 41 refs., 5 figs.

Rosenberg, T.J.; Singh, S.; Wu, C.S. [Univ. of Maryland, College Park, MD (United States); LaBelle, J.; Treumann, R.A. [Max-Planck-Institut fuer Physik und Astrophysik, Garching bei Muechen (Germany); Inan, U.S. [Stanford Univ., Stanford, CA (United States); Lanzerotti, L.J. [AT& T Bell Laboratories, Murray Hill, NJ (United States)

1995-01-01T23:59:59.000Z

63

Subionospheric VLF imaging of lightning-induced electron precipitation from the magnetosphere  

SciTech Connect

High-resoluton measurements of subionospheric VLF signals at multiple sites are used as a new tool to assess the spatial distribution and occurrence of ionospheric disturbances associated with lightning-induced electron precipitation. Simultaneous observations in California, Saskatchewan, and Quebec of VLF signals from multiple sources allow the monitoring of event activity over a course grid covering the continental US. Association of the observed VLF signal perturbations with lightning is often made on the basis of time correlation with prominent radio atmospherics. Simultaneous observations of individual events on subionospheric paths that cross one another are used to locate the disturbed ionospheric region(s). Absence of perturbations on nearby paths permits assessment of the spatial exstent of the region with a varying degree of accuracy, depending on the distribution of signal paths. In one case distinctly different onset delays (with respect to causative discharges) consistent with predictions of whistler-particle scattering theory were found, and were interpreted as being due to two separate regions separated in L value by {approximately} 0.4 L being excited in individual events. Occurrence statistics over the course of October 1987 exhibit generally higher levels of activity at the lower-latitude end of the 2 {lt} L {lt} 4 range, although it is difficult to separately assess the role of the source ligntning distribution. Occurrence statistics of simultaneous events on crossing paths are consistent with the spatial extent of the disturbed ionospheric regions being less than a few hundred kilometers. The occurrence statistics also suggest that scattering from disturbances located at distances of {gt} 100 km off the great circle paths is not significant.

Inan, U.S.; Knifsend, F.A.; Oh, J. (Stanford Univ., CA (United States))

1990-10-01T23:59:59.000Z

64

Long-range detection of VLF radiation produced by heating the auroral electrojet  

SciTech Connect

This paper presents the first evidence of long-range detection (greater than 1000 km) of calibrated VLF signals resulting from the HF heating of the auroral electrojet, that is, signal detection at a point of direct 'line of sight' of the heated patch of ionosphere. The 'radial' as well as the'azimuthal' magnetic component of the signals are recorded; from their ratio, the waveguide mode polarization is obtained. Observed absolute magnetic field strengths and waveguide polarizations are found to be in line with the predictions of simple waveguide models. 17 refs.

Barr, R.; Stubbe, P.; Kopka, H. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Federal Republic of Germany))

1991-08-01T23:59:59.000Z

65

Numerical simulation of whistler-triggered VLF emissions observed in Antartica  

SciTech Connect

The authors have extracted from VLF databases from British Antarctica Survey data taken at Halley and Faraday stations, examples of whistler-triggered emissions (WTE). The WTE are relatively narrow band emissions triggered by natural background whistlers undergoing nonlinear wave particle interactions generally in the equatorial regions. They occur with either rising or falling frequency relative to the triggering waves. Using a Vlasov type code the authors are able to simulate the types of emissions which are observed. 24 refs., 8 figs., 3 tabs.

Nunn, D. [Southhampton Univ., Southhampton (United Kingdom); Smith, A.J. [British Antarctic Survey, Cambridge (United Kingdom)

1996-03-01T23:59:59.000Z

66

Nonlocal theory of electromagnetic wave decay into two electromagnetic waves in a rippled density plasma channel  

SciTech Connect

Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.

Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)

2012-12-15T23:59:59.000Z

67

ELF/VLF emissions generated in the ionosphere by heating facilities - a new tool for ionospheric and magnetospheric research  

SciTech Connect

A brief summary of ELF/VLF generation experiments using the SURA heating facility is presented. The possibilities of applications of the measured ionospherically generated low frequency signal parameters for diagnosing the physical phenomena in the ionosphere and the magnetosphere are discussed.

Kotik, D.S. [Radiophysical Research Institute, Nizhny Novgorod (Russian Federation)

1994-12-01T23:59:59.000Z

68

Unmanned airborne vehicle (UAV): Flight testing and evaluation of two-channel E-field very low frequency (VLF) instrument  

SciTech Connect

Using VLF frequencies, transmitted by the Navy`s network, for airborne remote sensing of the earth`s electrical, magnetic characteristics was first considered by the United States Geological Survey (USGS) around the mid 1970s. The first VLF system was designed and developed by the USGS for installation and operation on a single engine, fixed wing aircraft used by the Branch of Geophysics for geophysical surveying. The system consisted of five channels. Two E-field channels with sensors consisting of a fixed vertical loaded dipole antenna with pre-amp mounted on top of the fuselage and a gyro stabilized horizontal loaded dipole antenna with pre-amp mounted on a tail boom. The three channel magnetic sensor consisted of three orthogonal coils mounted on the same gyro stabilized platform as the horizontal E-field antenna. The main features of the VLF receiver were: narrow band-width frequency selection using crystal filters, phase shifters for zeroing out system phase variances, phase-lock loops for generating real and quadrature gates, and synchronous detectors for generating real and quadrature outputs. In the mid 1990s the Branch of Geophysics designed and developed a two-channel E-field ground portable VLF system. The system was built using state-of-the-art circuit components and new concepts in circuit architecture. Small size, light weight, low power, durability, and reliability were key considerations in the design of the instrument. The primary purpose of the instrument was for collecting VLF data during ground surveys over small grid areas. Later the system was modified for installation on a Unmanned Airborne Vehicle (UAV). A series of three field trips were made to Easton, Maryland for testing and evaluating the system performance.

NONE

1998-12-01T23:59:59.000Z

69

Correlelations between the Anomalous Behaviour of the Ionosphere and the Seismic Events for VTX-MALDA VLF Propagation  

SciTech Connect

One of the most important application of the VLF signals is that it contains possible information about the lithosphere-ionosphere coupling. In other words, in near future, it may be possible to predict seismic events by judging signatures of VLF signals. In this paper, we present the result of the monitoring of the VLF signals collected in the Malda branch of ICSP, located in Malda, West Bengal, for four years (2005, 2007-09) and we try to find out the co-relations, if any, between the ionospheric activities and the earthquakes. Here we use that VLF signals which are transmitted from the VTX station (18.2 KHz), located near Vijayanarayanam in Tamilnadu, about 2290 km away from the receiver. To find out the co-relation of the ionospheric activities with the seismic events such as earthquake, first we have to study the average signal throughout the year. For this, we plot the so-called standardized calibration curve using the four years data. Here we use a total of 481 no. of data. To establish the co-relation between the ionospheric activities and the seismic events, we use the data of the year 2008 and we found that the deviations of the anomalous data are co-related with the seismic event. We found that the highest deviation takes place one day prior to the seismic events. We also calculated the 'D-layer preparation time'(DLPT) and the 'D-layer disappearance time'(DLDT) for the data of 2008 and tried to establish the co-relation between the anomalous DLPT and DLDT with the seismic events, if any. We compare our result with the VLF signals received from other places.

Ray, Suman; Sasmal, S. [Indian Centre for Space Physics, 43 Chalantika, Garia Station Road, Kolkata 700084 (India); Chakrabarti, S. K. [Indian Centre for Space Physics, 43 Chalantika, Garia Station Road, Kolkata 700084 (India); S. N. Bose National Centre for Basic Sciences, JD Block, Salt Lake, Kolkata 700098 (India); Choudhury, A. K. [Indian Centre for Space Physics, Malda Branch, Atul Market, Malda 731101 (India)

2010-10-20T23:59:59.000Z

70

Power System Electromagnetic Compatibility  

Science Conference Proceedings (OSTI)

The potential for man-made electromagnetic interference has existed since the construction of the first electric power system. As the use of electricity expanded during the first few decades of the twentieth century, the number of sources of electromagnetic interference, as well as the number of receptors, burgeoned. With the proliferation of sources and receptors, the engineering study of electromagnetic interference--sometimes called radio noise, electrical noise, or radio-frequency interference--becam...

2000-12-19T23:59:59.000Z

71

Tunability enhanced electromagnetic wiggler  

DOE Patents (OSTI)

The invention discloses a wiggler used in synchrotron radiation sources and free electron lasers, where each pole is surrounded by at least two electromagnetic coils. The electromagnetic coils are energized with different amounts of current to provide a wide tunable range of the on-axis magnetic flux density, while preventing magnetic saturation of the poles. 14 figs.

Schlueter, R.D.; Deis, G.A.

1992-03-24T23:59:59.000Z

72

Three-dimensional modeling of subionospheric VLF propagation in the presence of localized D region perturbations associated with lightning  

SciTech Connect

A theoretical model of single-mode, subionospheric VLF wave propagation in the presence of localized perturbations of the nighttime D region has been developed. Such perturbations could be produced, for example, by lightning-induced electron precipitation associated with a characteristic type of phase or amplitude perturbation in VLF signals known as Trimpi events. The model assumes that the ionospheric perturbation is slowly varying in the horizontal plane and that mode-coupling is therefore negligible, and accounts for (1) effects of perturbations with finite extent in the dimension transverse to the great circle (GC) path between transmitter and receiver, and (2) effects of perturbations which lie off the GC path as well as on it. The formulation used for the numerical calculations depends significantly on the mode refractive index of the ambient Earth-ionosphere waveguide and the mode refractive index in the region of the perturbation. In the calculations values for the mode refractive index are determined from the electron-density-versus-altitude profiles of both the ambient and perturbed ionospheres. Values for changes in the amplitude and phase of a received signal were obtained from the model and compared with amplitude and phase measurements of a VLF signal received at Palmer Station, Antarctica, from the NPM transmitter (23.4 kHz) in Hawaii during energetic electron precipitation events.

Poulsen, W.L.; Bell, T.F.; Inan, U.S. (Stanford Univ., CA (United States))

1990-03-01T23:59:59.000Z

73

Microslots : scalable electromagnetic instrumentation  

E-Print Network (OSTI)

This thesis explores spin manipulation, fabrication techniques and boundary conditions of electromagnetism to bridge the macroscopic and microscopic worlds of biology, chemistry and electronics. This work is centered around ...

Maguire, Yael G., 1975-

2004-01-01T23:59:59.000Z

74

Exploration of a lignite-bearing basin in Northern Ireland using ground magnetic and VLF-EM methods  

SciTech Connect

In an exploration technique feasibility study, a detailed magnetic and VLF-EM survey was carried out on the poorly exposed, lignite-bearing Crumlin subbasin within the Lough Neagh Basin, Co. Antrim, Northern Ireland. The faulted and onlapped margins of the basin, as well as lithological units and structures within the basin, were delineated by simple processing techniques applied to the data. The combination of the two methods overcomes the limitations of each method when it is used alone. These techniques could be successfully applied to other lignite-bearing basins sited on strongly magnetic basement worldwide.

McCaffrey, R.J.; McElroy, W.J.; Leslie, A.G. [Queen`s Univ. of Belfast (United Kingdom)

1995-03-01T23:59:59.000Z

75

Superconducting dipole electromagnet  

DOE Patents (OSTI)

A dipole electromagnet of especial use for bending beams in particle accelerators is wound to have high uniformity of magnetic field across a cross section and to decrease evenly to zero as the ends of the electromagnet are approached by disposing the superconducting filaments of the coil in the crescent-shaped nonoverlapping portions of two intersecting circles. Uniform decrease at the ends is achieved by causing the circles to overlap increasingly in the direction of the ends of the coil until the overlap is complete and the coil is terminated.

Purcell, John R. (San Diego, CA)

1977-07-26T23:59:59.000Z

76

Electromagnetic radiation detector  

DOE Patents (OSTI)

An electromagnetic radiation detector including a collimating window, a cathode member having a photoelectric emissive material surface angularly disposed to said window whereby radiation is impinged thereon at acute angles, an anode, separated from the cathode member by an evacuated space, for collecting photoelectrons emitted from the emissive cathode surface, and a negatively biased, high transmissive grid disposed between the cathode member and anode.

Benson, Jay L. (Albuquerque, NM); Hansen, Gordon J. (Albuquerque, NM)

1976-01-01T23:59:59.000Z

77

The Study of Electromagnetic Field Response Using Very Low Frequency Methods in Geothermal Area, Sabang  

SciTech Connect

Electromagnetic field measurements have been performed using the method of Very Low Frequency tilt angle pattern in Jaboi, Sabang. A site survey was conducted and carried out to identify the anomalies of location, depth and geometry of hydrothermal based on tilt angle measurement and ellipse. Objective of this study is to see the response of the magnetic and electric field in relation to location, depth and hydrothermal geometry. The devices of T-VLF-R IRIS was used in this study, while the (NWC) station was selected as main station and (JJF4) station was selected as comparison station. The electromagnetic field survey was recorded for a line spanned as long as 900 meters at the interval of 10 meter depth. The results of this study show the greatest anomaly occurred at line interval between 400-600 meters with a depth of 10-140 meters. Anomaly pattern of each depth shows that the propagation pattern of hydrothermal is in the form of vertical pipe flow.

Isa, M. [Departement of Physics Syiah Kuala University Banda Aceh, 23111 (Indonesia); School of Physics, Universiti Sains Malaysia 11800, Penang (Malaysia); Lim, H. S.; Jafri, M. Z. Mat [School of Physics, Universiti Sains Malaysia 11800, Penang (Malaysia)

2011-03-30T23:59:59.000Z

78

Electromagnetic Transients in Substations, Volumes 5: Test Data Tapes  

Science Conference Proceedings (OSTI)

EPRI has investigated high-frequency electromagnetic interference (EMI) resulting from high-voltage switching, lightning, and faults in substations. This report provides information about EMI levels to which equipment is exposed.

1993-08-19T23:59:59.000Z

79

Investigation of the polar electrojet-current system using radio-wave heating from a ground-based facility  

SciTech Connect

The High Power Auroral Stimulation (HIPAS) heating facility has been used to modulate D region ionospheric currents at high latitudes, producing very low frequency (VLF) radio wave emissions. The behavior of these ionospheric currents can be deduced from a comprehensive study of the VLF signals received at a local field site. This Paper examines the relationship between the VLF magnetic field strength measured on the ground and the intensity of an overhead electrojet current for the purpose of enhancing communications. The mapping of the polar electrojet current from the E region down through the D region, where it can then be modulated by the heater beam, is investigated. A finite difference solution to the electrojet mapping .problem is presented in which arbitrary conductivity profiles can be specified. Results have been obtained using a simple Cowling model of the electrojet. These results indicate that for electrojets flowing between 100 and 110 km with scale sizes in excess of 100 km, the mapping of the horizontal current density can be completely characterized in terms of the Pedersen and Hall conductivities. This indicates that the mapping becomes independent of scale sizes which exceed 100 km. A promising new diagnostic technique, for studying ionospheric D region currents, has been implemented using the HIPAS facility. This technique involves high frequency (HF) beam steering for localized VLF generation in the mapped region below electrojets. Beam steering has been used to estimate the strength and current distribution of the polar electrojet, and for charting the movements of overhead currents.

Werner, D.H.; Ferraro, A.J.; Brandt, R.G.

1990-10-01T23:59:59.000Z

80

ELECTROMAGNETIC PROPERTIES OF SUPERCONDUCTORS  

SciTech Connect

A method of calculating the response of superconductors to weak electromagnetic fields is formulated. The response is generated from a single- particle Green's function, defined in the presence of an electromagnetic perturbation, that satisfies the conditions imposed by guauge invariance and charge conservation. The response function is thus itself explicitly gauge invariant and charge conserving. The single-particle Green-s function is obtained by making Gorkov's factorizatation of the tiio-partiele Green's funetion in the presence oi the external field. The sy'mmetry' properties of the approximation are used to simplify the calculatioa. This is trivially' carried out in the London limit. An economieal derivation is thus obtaiaed of Anderson's result thai the Bardeen, Cooper, and Sehrieffer quasi particle excitations must be supplemented by collective excitation in order to satisfy the conservation laws. (auth)

Ambegaokar, V.; Kadanoff, L.P.

1961-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Banded electromagnetic stator core  

DOE Patents (OSTI)

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1994-04-05T23:59:59.000Z

82

Electromagnetic Transients Program (EMTP) Workbook  

Science Conference Proceedings (OSTI)

High-speed electromagnetic transients are often the controlling factor in transmission system design and operation. This workbook provides case studies for introducing the basics of electromagnetic transient analysis. Sample problems demonstrate analyses of such transients with the EMTP computer code.BackgroundThe electromagnetic transients program (EMTP) is a versatile and efficient computer program that utilities worldwide use for analyzing high-speed power ...

1986-09-30T23:59:59.000Z

83

Physics Out Loud - Electromagnetic Force  

NLE Websites -- All DOE Office Websites (Extended Search)

Detector Previous Video (Detector) Physics Out Loud Main Index Next Video (Electron Scattering) Electron Scattering Electromagnetic Force Cynthia Keppel, a nuclear physicist,...

84

Boundary effects of electromagnetic vacuum fluctuations on charged particles  

E-Print Network (OSTI)

The effects of electromagnetic vacuum fluctuations with the boundary on charged particles is investigated. They may be observed via an electron interference experiment near the conducting plate, where boundary effects of vacuum fluctuations are found significant on coherence reduction of the electrons. The dynamics of the charge under the influence of quantized electromagnetic fields with a conducting plate is also studied. The corresponding stochastic equation of motion is derived in the semiclassical approximation, and the behavior of the charge's velocity fluctuations is discussed.

Tai-Hung Wu; Jen-Tsung Hsiang; Da-Shin Lee

2007-11-19T23:59:59.000Z

85

Boundary effects of electromagnetic vacuum fluctuations on charged particles  

E-Print Network (OSTI)

The effects of electromagnetic vacuum fluctuations with the boundary on charged particles is investigated. They may be observed via an electron interference experiment near the conducting plate, where boundary effects of vacuum fluctuations are found significant on coherence reduction of the electrons. The dynamics of the charge under the influence of quantized electromagnetic fields with a conducting plate is also studied. The corresponding stochastic equation of motion is derived in the semiclassical approximation, and the behavior of the charge's velocity fluctuations is discussed.

Wu, Tai-Hung; Lee, Da-Shin

2007-01-01T23:59:59.000Z

86

Dangerous electromagnetic fields?  

NLE Websites -- All DOE Office Websites (Extended Search)

Dangerous electromagnetic fields? Dangerous electromagnetic fields? Name: Tommy T Joseph Location: N/A Country: N/A Date: N/A Question: Why are electromagnetic fields supposedly dangerous? Replies: I assume you are asking about power line frequency (60 Hz) fields, since they have been in the news lately. No one knows for sure that they are dangerous. There have been a few studies which seem to show an association between how close homes are to power lines, and the incidence of childhood cancer (mostly leukemia) in children living (or who have lived) in those homes. Other similar studies have not found such an association. In all the studies which have found an association, none has actually measured the fields. Studies which actually have measured the fields find no association. There is no known mechanism for 60 Hz fields to cause cancer. Furthermore, the classic "dose-response relationship," that is, the greater the dose, the greater the response, does not seem to work here. Many laboratory studies have found that 60 Hz fields have an effect on organisms under certain conditions, but none of the observed effects can be convincingly related to a hazard. The bottom line is, no one knows for sure. It is important to realize that it is impossible to prove that anything is completely safe. My personal opinion is that, if there is a risk, it must be very small, or it wouldn't be so hard to prove. I can supply some good unbiased references if you are interested.

87

Sandia National Laboratories: Electromagnetics: Main Page  

NLE Websites -- All DOE Office Websites (Extended Search)

Brochure Adobe Logo Related Links Pulsed Power ELECTROMAGNETIC TECHNOLOGY AT SANDIA NATIONAL LABORATORIES Electromagnetics (EM) is the study of the nature and interaction of...

88

Overview Of Electromagnetic Methods Applied In Active Volcanic Areas Of  

Open Energy Info (EERE)

Of Electromagnetic Methods Applied In Active Volcanic Areas Of Of Electromagnetic Methods Applied In Active Volcanic Areas Of Western United States Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Overview Of Electromagnetic Methods Applied In Active Volcanic Areas Of Western United States Details Activities (7) Areas (2) Regions (0) Abstract: A better understanding of active volcanic areas in the United States through electromagnetic geophysical studies received foundation from the many surveys done for geothermal exploration in the 1970's. Investigations by governmental, industrial, and academic agencies include (but are not limited to) mapping of the Cascades. Long Valley/Mono area, the Jemez volcanic field, Yellowstone Park, and an area in Colorado. For one example - Mt. Konocti in the Mayacamas Mountains, California - gravity,

89

Superconductors Programs/Projects in Electromagnetics  

Science Conference Proceedings (OSTI)

Superconductors Programs/Projects in Electromagnetics. Superconductor Electromechanics. Contact. General Information ...

2010-10-05T23:59:59.000Z

90

Electromagnetic Compatibility in Nuclear Power Plants  

SciTech Connect

Electromagnetic compatibility (EMC) has long been a key element of qualification for mission critical instrumentation and control (I&C) systems used by the U.S. military. The potential for disruption of safety-related I&C systems by electromagnetic interference (EMI), radio-frequency interference (RFI), or power surges is also an issue of concern for the nuclear industry. Experimental investigations of the potential vulnerability of advanced safety systems to EMI/RFI, coupled with studies of reported events at nuclear power plants (NPPs) that are attributed to EMI/RFI, confirm the safety significance of EMC for both analog and digital technology. As a result, Oak Ridge National Laboratory has been engaged in the development of the technical basis for guidance that addresses EMC for safety-related I&C systems in NPPs. This research has involved the identification of engineering practices to minimize the potential impact of EMI/RFI and power surges and an evaluation of the ambient electromagnetic environment at NPPs to tailor those practices for use by the nuclear industry. Recommendations for EMC guidance have been derived from these research findings and are summarized in this paper.

Ewing, P.D.; Kercel, S.W.; Korsah, K.; Wood, R.T.

1999-08-29T23:59:59.000Z

91

Guidelines for Electromagnetic Interference Testing  

Science Conference Proceedings (OSTI)

One issue that has been problematic for new plant equipment and especially for digital instrumentation and control (I&C) systems in recent years is electromagnetic compatibility (EMC). Guidance from the Nuclear Regulatory Commission (NRC), EPRI, and various standards organizations has been evolving for many years and generally converging. However, the NRC's most recent guidance, Regulatory Guide 1.180 Revision 1, and EPRI's most recent EMI Guideline (Guidelines for Electromagnetic Interference Testing in...

2008-02-21T23:59:59.000Z

92

Black Hole Thermodynamics and Electromagnetism  

E-Print Network (OSTI)

We show a strong parallel between the Hawking, Beckenstein black hole Thermodynamics and electromagnetism: When the gravitational coupling constant transform into the electromagnetic coupling constant, the Schwarzchild radius, the Beckenstein temperature, the Beckenstein decay time and the Planck mass transform to respectively the Compton wavelength, the Hagedorn temperature, the Compton time and a typical elementary particle mass. The reasons underlying this parallalism are then discussed in detail.

Burra G. Sidharth

2005-07-15T23:59:59.000Z

93

SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS  

DOE Green Energy (OSTI)

This research explores a new efficient approach for producing electricity from the abundant energy of the sun. A nanoantenna electromagnetic collector (NEC) has been designed, prototyped, and tested. Proof of concept has been validated. The device targets mid-infrared wavelengths where conventional photovoltaic (PV) solar cells do not respond but is abundant in solar energy. The initial concept of designing NEC antennas was based on scaling of radio frequency antenna theory. This approach has proven unsuccessful by many due to not fully understanding and accounting for the optical behavior of materials in the THz region. Also until recent years the nanofabrication methods were not available to fabricate the optical antenna elements. We have addressed and overcome both technology barriers. Several factors were critical in successful implementation of NEC including: 1) frequency-dependent modeling of antenna elements, 2) selection of materials with proper THz properties and 3) novel manufacturing methods that enable economical large-scale manufacturing. The work represents an important step toward the ultimate realization of a low-cost device that will collect as well as convert this radiation into electricity, which will lead to a wide spectrum, high conversion efficiency, and low cost solution to complement conventional PVs.

Steven D. Novack; Dale K. Kotter; Dennis Slafer; Patrick Pinhero

2008-08-01T23:59:59.000Z

94

Definition: Ground Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Ground Electromagnetic Techniques Jump to: navigation, search Dictionary.png Ground Electromagnetic Techniques Ground electromagnetic techniques measure electromagnetic fields in order to determine subsurface electrical resistivity with the earth surface as the observation point.[1] View on Wikipedia Wikipedia Definition The electromagnetic force is one of the four fundamental interactions in nature, the other three being the strong interaction, the weak interaction, and gravitation. This force is described by electromagnetic fields, and has innumerable physical instances including the interaction of electrically charged particles and the interaction of uncharged magnetic force fields with electrical conductors. The word

95

Frequency variations of quasi-periodic ELF-VLF emissions: A possible new ground-based diagnostic of the outer high-latitude magnetosphere  

SciTech Connect

Magnetic pulsations and quasi-periodic (QP) amplitude modulations of ELF-VLF waves at Pc 3-4 frequencies (15-50 mHz) are commonly observed simultaneously in cusp-latitude data. The naturally occurring ELF-VLF emissions are believed to be modulated within the magnetosphere by the compressional component of geomagnetic pulsations formed external to the magnetosphere. The authors have examined data from South Pole Station (L {approximately} 14) to determine the occurrence and characteristics of QP emissions. On the basis of 14 months of data during 1987 and 1988 they found that QP emissions typically appeared in both the 0.5-1 kHz and 1-2 kHz receiver channels at South Pole Station and ocassionally in the 2-4 kHz channel. The QP emission frequency appeared to depend on solar wind parameters and interplanetary magnetic field (IMF) direction, and the months near fall equinox in both 1987 and 1988 showed a significant increase in the percentage of QP emissions only in the lowest-frequency channel. The authors present a model consistent with these variations in which high-latitude (nonequatorial) magnetic field minima near the magnetopause play a major role, because the field magnitude governs both the frequency of ELF-VLF emissions and the whistler mode propagation cutoffs. Because the field in these regions will be strongly influenced by solar wind and IMF parameters, variations in the frequency of such emissions may be useful in providing ground-based diagnostics of the outer high-latitude magnetosphere. 32 refs., 13 figs.

Alford, J.; Engebretson, M. [Ausburg College, Minneapolis, MN (United States); Arnoldy, R. [Univ. of New Hampshire, Durham, NH (United States); Inan, U. [Stanford Univ., CA (United States)

1996-01-01T23:59:59.000Z

96

The ??? Amplitude in an External Homogeneous Electromagnetic  

E-Print Network (OSTI)

Neutrino-photon interactions in the presence of an external homogeneous constant electromagnetic field are studied. The ??? amplitude is calculated in an electromagnetic field of the general type, when the two field invariants are nonzero.

R. Shaisultanov

2000-01-01T23:59:59.000Z

97

Sympathetic Electromagnetically-Induced-Transparency Laser ...  

Science Conference Proceedings (OSTI)

Page 1. Sympathetic Electromagnetically-Induced-Transparency Laser Cooling of Motional Modes in an Ion Chain Y. Lin ...

2013-04-22T23:59:59.000Z

98

Unification of Gravity and Electromagnetism Revisited  

E-Print Network (OSTI)

Unification of gravity and electromagnetism based on a theory with an affine non-symmetric connection $\\Gamma^\\lambda_{\\mu\

Partha Ghose

2013-02-14T23:59:59.000Z

99

Airborne electromagnetic surveys as a reconnaissance technique...  

Open Energy Info (EERE)

electromagnetic surveys as a reconnaissance technique for geothermal exploration Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Airborne...

100

Current Sheet Canting in Pulsed Electromagnetic Accelerators  

E-Print Network (OSTI)

Current Sheet Canting in Pulsed Electromagnetic Accelerators Thomas Edward Markusic A DISSERTATION #12;Current Sheet Canting in Pulsed Electromagnetic Accelerators Prepared by: Thomas Edward Markusic of current sheet canting in pulsed electromagnetic accelerators is the de- parture of the plasma sheet

Choueiri, Edgar

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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101

The courts and electromagnetic fields  

Science Conference Proceedings (OSTI)

This article examines the recent development in eminent domain cases involving power transmission line rights of way, the issue of fear of the mythical buyer. The author feels that the fear of electrocution or of the possible cancer-inducing effects of electromagnetic fields is greatly influencing court decisions in these cases. The results could be more expensive rights of way acquisition by utilities.

Freeman, M. (Univ. of Pennsylvania, Philadelphia (United States))

1990-07-19T23:59:59.000Z

102

A current concern. [Electromagnetic fields  

SciTech Connect

This article examines the risk to homeowners of exposure to electromagnetic fields (EMF). Studies that link EMF to cancer are described and recommendations are given for prudent avoidance. Appliance manufacturers claim to have found no economically feasible way to shield emissions. Meanwhile the EPA's health effects research in this area has been suspended because of budgetary constraints.

Brinckerhoff, S.

1990-09-01T23:59:59.000Z

103

A multiple-mode three-dimensional model of VLF propagation in the earth-ionosphere waveguide in the presence of localized D region disturbances  

SciTech Connect

Transient localized D region disturbances, such as those associated with lightning discharges, affect the characteristics of VLF waves propagating in the Earth-ionosphere waveguide. In particular, both phase and amplitude changes in the subionospheric signal can be observed at receiving sites as a result of the wave scattering that takes place in the disturbed region. In the present paper we present a multiple-mode three- dimensional model of VLF propagation in the Earth-ionosphere waveguide in the presence of localized D region disturbances. The model takes into account great circle (GC) propagation paths with realistic ground and ionospheric conductivity changes that result in mode conversion along the path. It is assumed that conductivity changes transverse to the GC paths are negligible except in the vicinity of the D region disturbance and that mode coupling is negligible within the distributed region. This new model is applied to experimental observations and is found to be in general agreement. The diagnostics potential of the model for characterizing energetic particle precipitation events is discussed. 33 refs., 14 figs.

Poulsen, W.L.; Inan, U.S.; Bell, T.F. (Stanford Univ., CA (United States))

1993-02-01T23:59:59.000Z

104

RF Loading Effects of Aircraft Seats in an Electromagnetic Reverberating Environment  

Science Conference Proceedings (OSTI)

Loading effects of aircraft seats in an electromagnetic reverberating environment are investigated. The effects are determined by comparing the reverberation chamber''s insertion losses with and without the seats. The average per-seat absorption cross-sections ...

Nguyen Truong X.

2000-12-01T23:59:59.000Z

105

Definition: Electromagnetic Profiling Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Profiling Techniques Electromagnetic Profiling Techniques Jump to: navigation, search Dictionary.png Electromagnetic Profiling Techniques Electromagnetic profiling techniques map lateral variations in subsurface resistivity.[1] View on Wikipedia Wikipedia Definition Exploration geophysics is the applied branch of geophysics which uses surface methods to measure the physical properties of the subsurface Earth, along with the anomalies in these properties, in order to detect or infer the presence and position of ore minerals, hydrocarbons, geothermal reservoirs, groundwater reservoirs, and other geological structures. Exploration geophysics is the practical application of physical methods (such as seismic, gravitational, magnetic, electrical and electromagnetic) to measure the physical properties of rocks, and in particular, to detect

106

Electromagnetic Sounding Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Sounding Techniques Electromagnetic Sounding Techniques (Redirected from Electromagnetic Sounding Methods) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Electromagnetic Sounding Techniques Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Ground Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water

107

Ground Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Ground Electromagnetic Techniques Ground Electromagnetic Techniques (Redirected from Ground Electromagnetic Methods) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Ground Electromagnetic Techniques Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature

108

Correspondence between Electro-Magnetic Field and other Dark Energies in Non-linear Electrodynamics  

E-Print Network (OSTI)

In this work, we have considered the flat FRW model of the universe filled with electro-magnetic field. First, the Maxwell's electro-magnetic field in linear form has been discussed and after that the modified Lagrangian in non-linear form for accelerated universe has been considered. The corresponding energy density and pressure for non-linear electro-magnetic field have been calculated. We have found the condition such that the electro-magnetic field generates dark energy. The correspondence between the electro-magnetic field and the other dark energy candidates namely tachyonic field, DBI-essence, Chaplygin gas, hessence dark energy, k-essenece and dilaton dark energy have been investigated. We have also reconstructed the potential functions and the scalar fields in this scenario.

Maity, Sayani; Debnath, Ujjal

2011-01-01T23:59:59.000Z

109

Correspondence between Electro-Magnetic Field and other Dark Energies in Non-linear Electrodynamics  

E-Print Network (OSTI)

In this work, we have considered the flat FRW model of the universe filled with electro-magnetic field. First, the Maxwell's electro-magnetic field in linear form has been discussed and after that the modified Lagrangian in non-linear form for accelerated universe has been considered. The corresponding energy density and pressure for non-linear electro-magnetic field have been calculated. We have found the condition such that the electro-magnetic field generates dark energy. The correspondence between the electro-magnetic field and the other dark energy candidates namely tachyonic field, DBI-essence, Chaplygin gas, hessence dark energy, k-essenece and dilaton dark energy have been investigated. We have also reconstructed the potential functions and the scalar fields in this scenario.

Sayani Maity; Shuvendu Chakraborty; Ujjal Debnath

2011-04-12T23:59:59.000Z

110

Definition: Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Techniques Electromagnetic Techniques The objective of electromagnetic (EM) techniques is to image the electrical resistivity structure of the subsurface through the measurement of naturally- or artificially-generated electromagnetic fields.[1] View on Wikipedia Wikipedia Definition The electromagnetic force is one of the four fundamental interactions in nature, the other three being the strong interaction, the weak interaction, and gravitation. This force is described by electromagnetic fields, and has innumerable physical instances including the interaction of electrically charged particles and the interaction of uncharged magnetic force fields with electrical conductors. The word electromagnetism is a compound form of two Greek terms, ἢλεκτρον, ēlektron, "amber", and μαγνήτης, magnētēs, "magnet". The science

111

Questions and Answers - Which jobs use electromagnets?  

NLE Websites -- All DOE Office Websites (Extended Search)

does adding coils to anelectromagnet make it stronger? does adding coils to an<br>electromagnet make it stronger? Previous Question (Why does adding coils to an electromagnet make it stronger?) Questions and Answers Main Index Next Question (Why is a non-permanent, but long lasting, magnet called a permanent magnet?) Why is a non-permanent, but long lasting,magnet called a permanent magnet? Which jobs use electromagnets? In today's world almost all jobs other than a goat herder use some type of electromagnet. They are everywhere. Electric motors are a type of electromagnet. Cars have dozens of electromagnets that move things or generate electricity. There are all sorts of interesting applications for larger electromagnets. The most obvious and biggest example is electricity. There are some interesting applications like dumping shredded garbage

112

Very Low Frequency (VLF) Hipot Testing of Rotating Machine Stator Winding Insulation  

Science Conference Proceedings (OSTI)

High-potential (hipot) tests are performed to determine whether winding insulation in rotating electrical machinery has a minimum level of electrical strength to successfully survive electrical stresses in normal service for the expected life of the machine. In recent years, the Electric Power Research Institute (EPRI) has been engaged in helping to clarify industry practices and investigate questions about specific aspects of hipot testing. One topic of interest to the industry is the use of very-low-fr...

2011-12-23T23:59:59.000Z

113

Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Electromagnetic Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Electromagnetic Techniques Details Activities (0) Areas (0) Regions (0) NEPA(5) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electrical Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water

114

Category:Electromagnetic Sounding Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Sounding Techniques Electromagnetic Sounding Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Electromagnetic Sounding Techniques page? For detailed information on Electromagnetic Sounding Techniques, click here. Category:Electromagnetic Sounding Techniques Add.png Add a new Electromagnetic Sounding Techniques Technique Subcategories This category has only the following subcategory. M [×] Magnetotelluric Techniques‎ 1 pages Pages in category "Electromagnetic Sounding Techniques" The following 2 pages are in this category, out of 2 total. M Magnetotelluric Techniques T Time-Domain Electromagnetics Retrieved from "http://en.openei.org/w/index.php?title=Category:Electromagnetic_Sounding_Techniques&oldid=689837"

115

Electromagnetic Transients Program (EMTP) Application Guide  

Science Conference Proceedings (OSTI)

The electromagnetic transients program is a versatile computer program that utilities worldwide use to analyze high-speed power system transients. This application guide provides procedures and data to assist engineers experienced in electromagnetic transient analysis based on EMTP.BackgroundThe electromagnetic transients program (EMTP), developed in the early 1970s by the Bonneville Power Administration (BPA), has been widely used for transient analysis. To ...

1986-12-08T23:59:59.000Z

116

Electromagnetic Profiling Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Profiling Techniques Electromagnetic Profiling Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Electromagnetic Profiling Techniques Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Ground Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature

117

Detection of electromagnetic waves using MEMS antennas  

SciTech Connect

We describe the design, fabrication and characterization of simple micromechanical structures that are capable of sensing static electric time varying electromagnetic fields. Time varying electric field sensing is usually achieved using an electromagnetic antenna and a receiver. However, these antenna-based approaches do not exhibit high sensitivity over a broad frequency (or wavelength) range. An important aspect of the present work is that, in contrast to traditional antennas, the dimensions of these micromechanical oscillators can be much smaller than the wavelength of the electromagnetic wave. We characterized the fabricated micromechanical oscillators by measuring their responses to time varying electric and electromagnetic fields.

Lavrik, Nickolay V [ORNL; Tobin, [Oak Ridge National Laboratory (ORNL); Bowland, Landon T [ORNL

2011-01-01T23:59:59.000Z

118

Ground Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Ground Electromagnetic Techniques Ground Electromagnetic Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Ground Electromagnetic Techniques Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature Dictionary.png

119

Crosswell Electromagnetic Resistivity Imaging: Illuminating the Reservior |  

Open Energy Info (EERE)

Page Page Edit with form History Facebook icon Twitter icon » Crosswell Electromagnetic Resistivity Imaging: Illuminating the Reservior Jump to: navigation, search OpenEI Reference LibraryAdd to library Web Site: Crosswell Electromagnetic Resistivity Imaging: Illuminating the Reservior Published Middle East Asia Reservior Reviiew, 2006 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Crosswell Electromagnetic Resistivity Imaging: Illuminating the Reservior Citation Crosswell Electromagnetic Resistivity Imaging: Illuminating the Reservior [Internet]. 2006. Middle East Asia Reservior Reviiew. [cited 2013/10/22]. Available from: http://www.slb.com/~/media/Files/resources/mearr/num7/illuminating_reservoir.pdf Retrieved from

120

Electromagnetic Sounding Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Sounding Techniques Electromagnetic Sounding Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Electromagnetic Sounding Techniques Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Ground Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Time-Domain Electromagnetics | Open Energy Information  

Open Energy Info (EERE)

Time-Domain Electromagnetics Time-Domain Electromagnetics Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Time-Domain Electromagnetics Details Activities (10) Areas (10) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Sounding Techniques Information Provided by Technique Lithology: Detection of rock units or geological features with contrasting apparent resistivity. Stratigraphic/Structural: Structural information may be inferred from TDEM data. Hydrological: Hydrological information such as depth to groundwater table may be determined. Thermal: Extent of hydrothermal alteration mineralogy may be inferred. Cost Information

122

Definition: Electromagnetic Sounding Techniques | Open Energy...  

Open Energy Info (EERE)

Sounding Techniques Electromagnetic soundings aim to map the distribution of electrical resistivity as a function of depth.1 References http:www.amazon.com...

123

22.105 Electromagnetic Interactions, Fall 1998  

E-Print Network (OSTI)

Principles and applications of electromagnetism, starting from Maxwell's equations, with emphasis on phenomena important to nuclear engineering and radiation sciences. Solution methods for electrostatic and magnetostatic ...

Hutchinson, I. H. (Ian H.)

124

Algebraic sub-structuring for electromagnetic applications  

E-Print Network (OSTI)

Li, I. Malik, W. M i , C. Ng, and M . Wolf. ElectromagneticP. Husbands, and E. G. Ng. An Alge- braic Sub-structuring

2004-01-01T23:59:59.000Z

125

Electromagnetic weak turbulence theory revisited  

SciTech Connect

The statistical mechanical reformulation of weak turbulence theory for unmagnetized plasmas including fully electromagnetic effects was carried out by Yoon [Phys. Plasmas 13, 022302 (2006)]. However, the wave kinetic equation for the transverse wave ignores the nonlinear three-wave interaction that involves two transverse waves and a Langmuir wave, the incoherent analogue of the so-called Raman scattering process, which may account for the third and higher-harmonic plasma emissions. The present paper extends the previous formalism by including such a term.

Yoon, P. H. [IPST, University of Maryland, College Park, Maryland 20742 (United States); Ziebell, L. F. [Instituto de Fisica, UFRGS, Porto Alegre, RS (Brazil); Gaelzer, R.; Pavan, J. [Instituto de Fisica e Matematica, UFPel, Pelotas, RS (Brazil)

2012-10-15T23:59:59.000Z

126

Electromagnetic dissociation of relativistic {sup 28}Si by nucleon emission  

SciTech Connect

A detailed study of the electromagnetic dissociation of {sup 28}Si by nucleon emission at E{sub lab}/A = 14.6 (GeV/nucleon was carried out with {sup 28}Si beams interacting on {sup 208}Pb). {sup 120}Sn. {sup 64}C targets. The measurements apparatus consists of detectors in the target area which measure the energy and charged multiplicity, and a forward spectrometer which measures the position, momentum and energy of the reaction fragments. The exclusive electromagnetic dissociation cross sections for decay channels having multiple nucleons in the final state have been measured which enables the selection of events produced in pure electromagnetic interactions. The measured cross sections agree well with previous measurements obtained for the removal of a few nucleons as well as with measurements on total charge removal cross sections from other experiments. The dependence of the integrated cross sections on the target charge Z{sub T} and the target mass AT confirms that for higher Z targets the excitation is largely electromagnetic. Direct measurements of the excitation energy for the electromagnetic dissociation of {sup 28}Si {yields} p+{sup 27}Al and {sup 28}Si {yields} n+{sup 27}Si have been obtained through a calculation of the invariant mass in kinematically, reconstructed events. The excitation energy spectrum for all targets peak near the isovector giant dipole resonance in {sup 28}Si. These distributions are well reproduced by combining the photon spectrum calculated using the Weizsaecker-Williams approximation with the experimental data on the photonuclear {sup 28}Si({sub {gamma},p}){sup 27}Al and {sup 28}Si({sub {gamma},n}){sup 27}Si. The possibilities of observing double giant dipole resonance excitations in {sup 28}Si have been investigated with cross section measurements as well as with excitation energy reconstruction.

Sonnadara, U.J.

1992-12-01T23:59:59.000Z

127

Electromagnetic dissociation of relativistic [sup 28]Si by nucleon emission  

SciTech Connect

A detailed study of the electromagnetic dissociation of [sup 28]Si by nucleon emission at E[sub lab]/A = 14.6 (GeV/nucleon was carried out with [sup 28]Si beams interacting on [sup 208]Pb). [sup 120]Sn. [sup 64]C targets. The measurements apparatus consists of detectors in the target area which measure the energy and charged multiplicity, and a forward spectrometer which measures the position, momentum and energy of the reaction fragments. The exclusive electromagnetic dissociation cross sections for decay channels having multiple nucleons in the final state have been measured which enables the selection of events produced in pure electromagnetic interactions. The measured cross sections agree well with previous measurements obtained for the removal of a few nucleons as well as with measurements on total charge removal cross sections from other experiments. The dependence of the integrated cross sections on the target charge Z[sub T] and the target mass AT confirms that for higher Z targets the excitation is largely electromagnetic. Direct measurements of the excitation energy for the electromagnetic dissociation of [sup 28]Si [yields] p+[sup 27]Al and [sup 28]Si [yields] n+[sup 27]Si have been obtained through a calculation of the invariant mass in kinematically, reconstructed events. The excitation energy spectrum for all targets peak near the isovector giant dipole resonance in [sup 28]Si. These distributions are well reproduced by combining the photon spectrum calculated using the Weizsaecker-Williams approximation with the experimental data on the photonuclear [sup 28]Si([sub [gamma],p])[sup 27]Al and [sup 28]Si([sub [gamma],n])[sup 27]Si. The possibilities of observing double giant dipole resonance excitations in [sup 28]Si have been investigated with cross section measurements as well as with excitation energy reconstruction.

Sonnadara, U.J.

1992-12-01T23:59:59.000Z

128

Category:Ground Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Ground Electromagnetic Techniques Ground Electromagnetic Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Ground Electromagnetic Techniques page? For detailed information on Ground Electromagnetic Techniques, click here. Category:Ground Electromagnetic Techniques Add.png Add a new Ground Electromagnetic Techniques Technique Subcategories This category has the following 2 subcategories, out of 2 total. E [×] Electromagnetic Profiling Techniques‎ 1 pages [+] Electromagnetic Sounding Techniques‎ (1 categories) 2 pages Pages in category "Ground Electromagnetic Techniques" The following 2 pages are in this category, out of 2 total. E Electromagnetic Profiling Techniques Electromagnetic Sounding Techniques Retrieved from "http://en.openei.org/w/index.php?title=Category:Ground_Electromagnetic_Techniques&oldid=689834"

129

Electromagnetic energy within magnetic spheres  

E-Print Network (OSTI)

Consider that an incident plane wave is scattered by a homogeneous and isotropic magnetic sphere of finite radius. We determine, by means of the rigorous Mie theory, an exact expression for the time-averaged electromagnetic energy within this particle. For magnetic scatterers, we find that the value of the average internal energy in the resonance picks is much larger than the one associated with a scatterer with the same nonmagnetic medium properties. This result is valid even, and specially, for low size parameter values. Expressions for the contributions of the radial and angular field components to the internal energy are determined. For the analytical study of the weak absorption regime, we derive an exact expression for the absorption cross section in terms of the magnetic Mie internal coefficients. We stress that although the electromagnetic scattering by particles is a well-documented topic, almost no attention has been devoted to magnetic scatterers. Our aim is to provide some new analytical results, which can be used for magnetic particles, and empha- size the unusual properties of the magnetic scatters, which could be important in some applications.

Tiago Jose Arruda; Alexandre Souto Martinez

2010-10-14T23:59:59.000Z

130

Electromagnetic form factors of hadrons  

SciTech Connect

A vector meson dominance model of the electromagnetic form factors of hadrons is developed which is based on the use of unstable particle propagators. Least-square fits are made to the proton, neutron, pion and kaon form factor data in both the space and time-like regions. A good fit to the low-energy nucleon form factor data is obtained using only rho, $omega$, and phi dominance, and leads to a determination of the vector meson resonance parameters in good agreement with experiment. The nucleon-vector meson coupling constants obey simple sum rules indicating that there exists no hard core contribution to the form factors within theoretical uncertainties. The prediction for the electromagnetic radii of the proton is in reasonable agreement with recent experiments. The pion and kaon charge form factors as deduced from the nucleon form factors assuming vector meson universality are compared to the data. The pion form factor agrees with the data in both the space and time-like regions. The pion charge radius is in agreement with the recent Dubna result, but the isovector P-wave pion-pion phase shift calculated from the theory disagrees with experiment. A possible contribution to the form factors from a heavy rho meson is also evaluated. (auth)

Zidell, V.S.

1976-01-01T23:59:59.000Z

131

Electromagnetic Transients Program (EMTP) Workbook II  

Science Conference Proceedings (OSTI)

The complex and versatile EMTP computer program can help utilities analyze electromagnetic transients, which affect the design and operation of power systems. A workbook published in 1986 introduced basic EMTP concepts.To guide advanced users, EPRI and the EMTP Development Coordination Group cosponsored the preparation of three workbooks on complicated program applications.BackgroundStudies of electromagnetic transients were traditionally performed with special ...

1989-07-18T23:59:59.000Z

132

Electromagnetic Transients Program (EMTP) Workbook IV  

Science Conference Proceedings (OSTI)

The complex and versatile EMTP computer program can help utilities analyze electromagnetic transients, which affect the design and operation of power systems. A workbook published in 1986 introduced basic EMTP concepts. To guide advanced users, EPRI and the EMTP Development Coordination Group cosponsored the preparation of three workbooks on complicated program applications.BackgroundStudies of electromagnetic transients were traditionally performed with special ...

1989-07-18T23:59:59.000Z

133

Electromagnetic Transients Program (EMTP) Workbook III  

Science Conference Proceedings (OSTI)

The complex and versatile EMTP computer program can help utilities analyze electromagnetic transients, which affect the design and operation of power systems. A workbook published in 1986 introduced basic EMTP concepts.To guide advanced users, EPRI and the EMTP Development Coordination Group cosponsored the preparation of three workbooks on complicated program applications.BackgroundStudies of electromagnetic transients were traditionally performed with special ...

1989-07-06T23:59:59.000Z

134

Narrow field electromagnetic sensor system and method  

DOE Patents (OSTI)

A narrow field electromagnetic sensor system and method of sensing a characteristic of an object provide the capability to realize a characteristic of an object such as density, thickness, or presence, for any desired coordinate position on the object. One application is imaging. The sensor can also be used as an obstruction detector or an electronic trip wire with a narrow field without the disadvantages of impaired performance when exposed to dirt, snow, rain, or sunlight. The sensor employs a transmitter for transmitting a sequence of electromagnetic signals in response to a transmit timing signal, a receiver for sampling only the initial direct RF path of the electromagnetic signal while excluding all other electromagnetic signals in response to a receive timing signal, and a signal processor for processing the sampled direct RF path electromagnetic signal and providing an indication of the characteristic of an object. Usually, the electromagnetic signal is a short RF burst and the obstruction must provide a substantially complete eclipse of the direct RF path. By employing time-of-flight techniques, a timing circuit controls the receiver to sample only the initial direct RF path of the electromagnetic signal while not sampling indirect path electromagnetic signals. The sensor system also incorporates circuitry for ultra-wideband spread spectrum operation that reduces interference to and from other RF services while allowing co-location of multiple electronic sensors without the need for frequency assignments. 12 figs.

McEwan, T.E.

1996-11-19T23:59:59.000Z

135

Noninvasive valve monitor using alternating electromagnetic field  

SciTech Connect

One or more electrical coils are carefully located on the outside of a valve body. An alternating current passing through the coil(s) results in an alternating electromagnetic field being transmitted into the valve body and valve internals. The electromagnetic field varies in intensity and polarity in the valve. As the position of a valve internal part is changed, the electromagnetic field throughout the valve body and its internals is altered. A passive receiver coil carefully located on the outside of the valve body detects the intensity of the electromagnetic field at that location as an induced electrical voltage in the coil. With the change in position of the valve internal part, there is a corresponding change in the induced voltage as a result of the alteration in the alternating electromagnetic field at that location. Changes in the voltage provide an indication of the position and motion of valve internals.

Eissenberg, David M. (Oak Ridge, TN); Haynes, Howard D. (Knoxville, TN); Casada, Donald A. (Knoxville, TN)

1993-01-01T23:59:59.000Z

136

Compton Gamma Ray Observatory/BATSE observations of energetic electrons scattered by cyclotron resonance with waves from powerful VLF transmitters. Final report, 13 October 1992-12 February 1994  

SciTech Connect

To obtain a better understanding of the wave-particle mechanisms responsible for the loss of electrons from the radiation belts, energetic electron data from the Burst and Transient Source Experiment (BATSE) on the NASA's Compton Gamma Ray Observatory (GRO) was studied. Powerful ground-based VLF transmitters resonantly scatter electrons from the inner radiation belt onto trajectories from which they precipitate into the atmosphere as they drift eastward. 563 instances in which the satellite traversed a cloud of energetic electrons which had been scattered into quasi-trapped trajectories were identified. From the longitude distribution, it was concluded that waves from the VLF transmitter NWC at 114 deg E are the origin of 257 of the events, and waves from UMSat 44 deg E related to 45 more. In another 177 cases the electrons had drifted from the longitude of these transmitters to a location in the western hemisphere. The previously reported seasonal variation in the frequency of occurrence of cyclotron resonance interaction is confirmed with the continuous coverage provided by GRO. The frequency of occurrence of the cyclotron resonance interactions is largest before sunrise, which the authors attribute to the diurnal variations in the transmission VLF waves through the ionosphere. For the first time, unique very narrow sheets of electrons occurring in the aftermath of a large geomagnetic storm are reported.

Datlowe, D.W.; Imhof, W.L.

1994-02-01T23:59:59.000Z

137

Coupled Electromagnetic and Thermal Modeling of Microwave Tissue Processing  

E-Print Network (OSTI)

This study deals with 3D finite element modeling of microwave tissue processing using Comsol software 4.0. Maxwells equations are coupled with heat conduction equation to determine electromagnetic field distribution and temperature profile within tissue sample in a reagent inside a domestic microwave oven. The microwave power generation term is calculated. Also, temperature distribution obtained is compared with experimental point measurements recorded in the centre of the tissue using a shielded K type thermocouple. Good agreement is found between numerical and experimental data. The effect of size of both reagent and tissue as well as tissue type on microwave heating patterns within tissue sample is investigated. Studies shows that the reagent volume has greater effect than other factors. The results of the study is considered as a basic foundation for development of coupled electromagnetic thermal models of microwave heating of tissue specimens. The model assists in choosing appropriate process parameters for achieving uniform temperature distribution within tissue specimen.

Osama A Hassan; Ahmed H K; Il Ences; Ahmed M El Bialy

2013-01-01T23:59:59.000Z

138

Airborne Electromagnetic Survey | Open Energy Information  

Open Energy Info (EERE)

Airborne Electromagnetic Survey Airborne Electromagnetic Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Airborne Electromagnetic Survey Details Activities (2) Areas (2) Regions (0) NEPA(1) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Techniques Information Provided by Technique Lithology: provide data on rock type and mineral content Stratigraphic/Structural: Hydrological: can be used to detect changes in density of fluids and indicate if there is salt water intrusion Thermal: Cost Information Low-End Estimate (USD): 48.274,827 centUSD 0.0483 kUSD 4.827e-5 MUSD 4.827e-8 TUSD / mile Median Estimate (USD): 317.3831,738 centUSD 0.317 kUSD

139

Magnesium Metal Matrix Nanocomposites By Electromagnetic ...  

Science Conference Proceedings (OSTI)

EMAT transforms electromagnetic energy into high intensity sonication to induce ... In the current work, the physics of acoustic production, the initial conditions of ... Department of Energy's Energy Efficiency and Renewable Energy Industrial...

140

Electrical, electromagnetic, and magnetotelluric methods | Open Energy  

Open Energy Info (EERE)

Electrical, electromagnetic, and magnetotelluric methods Electrical, electromagnetic, and magnetotelluric methods Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Electrical, electromagnetic, and magnetotelluric methods Abstract Application of electrical methods began with Robert W. Fox's 1830 observation of self potentials associated with copper vein deposits in Cornwall. Conrad Schlumberger introduced the direct current equal potential line resistivity method in 1912. Harry W. Conklin received the first patents on the electromagnetic (EM) method in 1917. From these beginnings, the history of the development of the resistivity induced-polarization (IP), magnetotelluric and EM methods are traced to the present time. It is of interest to note that application of electrical methods flourished from

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Do you know what an electromagnet is?  

NLE Websites -- All DOE Office Websites (Extended Search)

Do you know what an electromagnet is? Boy did you come to the right place and ask the right question. Jefferson Lab is magnet central to the world. Several of the world's most...

142

An Acoustic Doppler and Electromagnetic Velocity Profiler  

Science Conference Proceedings (OSTI)

A freely failing current meter called the Absolute Velocity Profiler (AVP) is described. This profiler is an expansion of a previously developed instrument, the Electro-Magnetic Velocity Profiler (EMVP), with the additional capability of acoustic ...

Thomas B. Sanford; Robert G. Driver; John H. Dunlap

1985-06-01T23:59:59.000Z

143

SP-100 thermoelectric-electromagnetic pump review  

DOE Green Energy (OSTI)

This report contains vugraphs of a presentation on thermoelectric-electromagnetic pumps. It contains: engineering drawings; summary of rectangular TEMP results and comparison with GE predictions; and results of optimization study.

NONE

1988-12-31T23:59:59.000Z

144

Advances in non-planar electromagnetic prototyping  

E-Print Network (OSTI)

The advent of metamaterials has introduced new ways to manipulate how electromagnetic waves reflect, refract and radiate in systems where the range of available material properties now includes negative permittivity, ...

Ehrenberg, Isaac M

2013-01-01T23:59:59.000Z

145

Electromagnetic Pulse (EMP) and the Power Grid  

Science Conference Proceedings (OSTI)

Thisdocument provides background and an introduction to the topic of electromagnetic pulse (EMP, including high-altitude EMP or HEMP) for stakeholders concerned about potential damage to power grid infrastructures.

2013-08-21T23:59:59.000Z

146

Dynamic programming applied to electromagnetic satellite actuation  

E-Print Network (OSTI)

Electromagnetic formation flight (EMFF) is an enabling technology for a number of space mission architectures. While much work has been done for EMFF control for large separation distances, little work has been done for ...

Eslinger, Gregory John

2013-01-01T23:59:59.000Z

147

Electrical wire insulation and electromagnetic coil  

DOE Patents (OSTI)

An electromagnetic coil for high temperature and high radiation application in which glass is used to insulate the electrical wire. A process for applying the insulation to the wire is disclosed which results in improved insulation properties.

Bich, George J. (Penn Hills, PA); Gupta, Tapan K. (Monroeville, PA)

1984-01-01T23:59:59.000Z

148

Deep electromagnetic sounding in central Nevada  

DOE Green Energy (OSTI)

Sixteen shallow and deep controlled source electromagnetic soundings were performed in Buena Vista Valley, near Winnemucca, Nevada, to investigate an intra-basement conductor previously detected with magnetotellurics. The survey was carried out with the LBL EM-60 system using a remote magnetic reference for low-frequency geomagnetic noise cancellation, 100-m- and 2.8-km-diameter transmitter loops, and a minicomputer for in-field processing. EM soundings were made at distances from 0.5 to 30 km from three loops over the frequency range 0.02 to 500 Hz. Data were interpreted by means of 1-D inversions and the resulting layered models were pieced together to yield an approximate 2-D geoelectric model along the N-S axis of the valley. The EM soundings and one MT sounding show a 3 to 7 ohm-m zone at a depth of four to seven km. The conductor appears to be deepest at the northern end of the valley and shallowest beneath a basement ridge that seems to divide Buena Vista Valley into two basinal structures. Similar intra-basement conductors are also reported 50 to 75 miles south in the Carson Sink-Fallon areas, suggesting a common source, probably related to an anomalously hot, thin crust.

Wilt, M.; Goldstein, N.E.; Haught, J.R.; Morrison, H.F.

1982-04-01T23:59:59.000Z

149

Generating highly uniform electromagnetic field characteristics  

DOE Patents (OSTI)

An apparatus and method for generating homogenous electromagnetic fields within a volume. The homogeneity provided may be for magnetic and/or electric fields, and for field magnitude, radial gradient, or higher order radial derivative. The invention comprises conductive pathways oriented about a desired region of homogeneity. A corresponding apparatus and method is provided for substantially canceling the electromagnetic field outside of the apparatus, comprising a second set of conductive pathways placed outside the first set.

Crow, James T. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

150

Generating highly uniform electromagnetic field characteristics  

DOE Patents (OSTI)

An apparatus and method for generating homogenous electromagnetic fields within a volume. The homogeneity provided may be for magnetic and/or electric fields, and for field magnitude, radial gradient, or higher order radial derivative. The invention comprises conductive pathways oriented mirror symmetrically about a desired region of homogeneity. A corresponding apparatus and method is provided for substantially canceling the electromagnetic field outside of the apparatus, comprising a second set of conductive pathways placed outside the first set.

Crow, James Terry (Albuquerque, NM)

1998-01-01T23:59:59.000Z

151

Generating highly uniform electromagnetic field characteristics  

DOE Patents (OSTI)

An apparatus and method for generating homogenous electromagnetic fields within a volume. The homogeneity provided may be for magnetic and/or electric fields, and for field magnitude, radial gradient, or higher order radial derivative. The invention comprises conductive pathways oriented mirror symmetrically about a desired region of homogeneity. A corresponding apparatus and method is provided for substantially cancelling the electromagnetic field outside of the apparatus, comprising a second set of conductive pathways placed outside the first set.

Crow, James T. (Albuquerque, NM)

1997-01-01T23:59:59.000Z

152

Generating highly uniform electromagnetic field characteristics  

DOE Patents (OSTI)

An apparatus and method are disclosed for generating homogeneous electromagnetic fields within a volume. The homogeneity provided may be for magnetic and/or electric fields, and for field magnitude, radial gradient, or higher order radial derivative. The invention comprises conductive pathways oriented mirror symmetrically about a desired region of homogeneity. A corresponding apparatus and method is provided for substantially canceling the electromagnetic field outside of the apparatus, comprising a second set of conductive pathways placed outside the first set. 26 figs.

Crow, J.T.

1997-06-24T23:59:59.000Z

153

Generating highly uniform electromagnetic field characteristics  

DOE Patents (OSTI)

An apparatus and method for generating homogeneous electromagnetic fields within a volume is disclosed. The homogeneity provided may be for magnetic and/or electric fields, and for field magnitude, radial gradient, or higher order radial derivative. The invention comprises conductive pathways oriented mirror symmetrically about a desired region of homogeneity. A corresponding apparatus and method is provided for substantially canceling the electromagnetic field outside of the apparatus, comprising a second set of conductive pathways placed outside the first set. 39 figs.

Crow, J.T.

1998-02-10T23:59:59.000Z

154

Generating highly uniform electromagnetic field characteristics  

DOE Patents (OSTI)

An apparatus and method are disclosed for generating homogeneous electromagnetic fields within a volume. The homogeneity provided may be for magnetic and/or electric fields, and for field magnitude, radial gradient, or higher order radial derivative. The invention comprises conductive pathways oriented about a desired region of homogeneity. A corresponding apparatus and method is provided for substantially canceling the electromagnetic field outside of the apparatus, comprising a second set of conductive pathways placed outside the first set. 55 figs.

Crow, J.T.

1998-05-05T23:59:59.000Z

155

Electromagnetic fields in cased borehole  

DOE Green Energy (OSTI)

Borehole electromagnetic (EM) measurements, using fiberglass-cased boreholes, have proven useful in oil field reservoir characterization and process monitoring (Wilt et al., 1995). It has been presumed that these measurements would be impossible in steel-cased wells due to the very large EM attenuation and phase shifts. Recent laboratory and field studies have indicated that detection of EM signals through steel casing should be possible at low frequencies, and that these data provide a reasonable conductivity image at a useful scale. Thus, we see an increased application of this technique to mature oilfields, and an immediate extension to geothermal industry as well. Along with the field experiments numerical model studies have been carried out for analyzing the effect of steel casing to the EM fields. The model used to be an infinitely long uniform casing embedded in a homogeneous whole space. Nevertheless, the results indicated that the formation signal could be accurately recovered if the casing characteristics were independently known (Becker et al., 1998; Lee el al., 1998). Real steel-cased wells are much more complex than the simple laboratory models used in work to date. The purpose of this study is to develop efficient numerical methods for analyzing EM fields in realistic settings, and to evaluate the potential application of EM technologies to cross-borehole and single-hole environment for reservoir characterization and monitoring.

Lee, Ki Ha; Kim, Hee Joon; Uchida, Toshihiro

2001-07-20T23:59:59.000Z

156

Electrical, electromagnetic and structural characteristics of carbon nanotube-polymer nanocomposites  

E-Print Network (OSTI)

Composites for Electromagnetic Interference Shielding. NanoY. Ma, et al. Electromagnetic Interference (EMI) Shieldingof Bonn). Chung DDL. Electromagnetic interference shielding

Park, Sung-Hoon

2009-01-01T23:59:59.000Z

157

INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS  

Science Conference Proceedings (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. Battelle has completed the second year of work on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall. The second semiannual report on this project reported on experimental and modeling results. The results showed that the rotating system was more adaptable to pipeline inspection and therefore only this system will be carried into the second year of the sensor development. In the third reporting period, the rotating system inspection was further developed. Since this is a new inspection modality without published fundamentals to build upon, basic analytical and experimental investigations were performed. A closed form equation for designing rotating exciters and positioning sensors was derived from fundamental principles. Also signal processing methods were investigated for detection and assessment of pipeline anomalies. A lock in amplifier approach was chosen as the method for detecting the signals. Finally, mechanical implementations for passing tight restrictions such as plug valves were investigated. This inspection concept is new and unique; a United States patent application has been submitted. In this fourth reporting period, the rotating system inspection was further developed. A multichannel real-time data recorder system was implemented and fundamental experiments were conducted to provide data to aid in the design of the rotating magnetizer system. An unexpected but beneficial result was achieved when examining the separation between the rotating magnet and the pipe wall; separations of over an inch could be tolerated. Essentially no change in signal from corrosion anomalies could be detected for separations up to 1.35 inches. The results presented in this report will be used to achieve the next deliverable, designs of components of the rotating inspection system that will function with inspection crawlers in a pipeline environment.

J. Bruce Nestleroth

2005-11-30T23:59:59.000Z

158

Low-Frequency Electromagnetic Backscatter from Buried Tunnels  

Science Conference Proceedings (OSTI)

This progress report is submitted under a contract between the Special Project Office of DARPA and Lawrence Livermore National Laboratory. The Project Manager at DARPA is Dr. Michael Zatman. Our purpose under this contract is to investigate interactions between electromagnetic waves and a class of buried targets located in multilayered media with rough interfaces. In this report, we investigate three preliminary problems. In each case our specific goal is to understand various aspects of the electromagnetic wave interaction mechanisms with targets in layered media. The first problem, discussed in Section 2, is that of low-frequency electromagnetic backscattering from a tunnel that is cut into a lossy dielectric half-space. In this problem, the interface between the upper (free space) region and the lower (ground) region is smooth. The tunnel is assumed to be a cylindrical free-space region of infinite extent in its axial direction and with a diameter that is small in comparison to the free-space wavelength. Because its diameter is small, the tunnel can be modeled as a buried ''wire'' described by an equivalent impedance per unit length. In Section 3 we extend the analysis to include a statistically rough interface between the air and ground regions. The interface is modeled as a random-phase screen. Such a screen reduces the coherent power in a plane wave that is transmitted through it, scattering some of the total power into an incoherent field. Our analysis of this second problem quantifies the reduction in the coherent power backscattered from the buried tunnel that is caused by the roughness of the air-ground interface. The problem of low-frequency electromagnetic backscattering from two buried tunnels, parallel to each other but at different locations in the ground, is considered in Section 4. In this analysis, we wish to determine the conditions under which the presence of more than one tunnel can be detected via backscattering. Section 5 concludes the report with a summary of the investigations discussed herein and recommendations for future work on problems of this class.

Casey, K; Pao, H

2006-06-21T23:59:59.000Z

159

Electromagnetic Isotope Separation Lab (EMIS) | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Electromagnetic Isotope Separation Lab Electromagnetic Isotope Separation Lab May 30, 2013 ORNL established the Stable Isotope Enrichment Laboratory (SIEL) as part of a project funded by the DOE Office of Science, Nuclear Physics Program to develop a modernized electromagnetic isotope separator (EMIS), optimized for separation of a wide range of stable isotopes. The SIEL is located in the Building 6010 Shield Test Station, space formerly allocated to the Oak Ridge Electron Linear Accelerator, on the main campus of ORNL. ORNL staff have designed and built a nominal 10 mA ion current EMIS (sum of all isotopes at the collector) in the SIEL. This EMIS is currently being tested to determine basic performance metrics such as throughput and enrichment factor per pass. This EMIS unit and space will be used to

160

Topology optimization for the design of periodic microstructures composed of electromagnetic materials  

Science Conference Proceedings (OSTI)

Electromagnetic structures that incorporate certain structural periodicities are known to display special behavior when subjected to electromagnetic waves, and can be designed to have specific functions such as inhibiting the intrusion of electromagnetic ... Keywords: Electromagnetic field, Periodic boundary, Topology optimization

Tsuyoshi Nomura; Shinji Nishiwaki; Kazuo Sato; Koichi Hirayama

2009-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Helicopter Electromagnetic Survey of the Model Land Area, Southeastern Miami-Dade County, Florida  

E-Print Network (OSTI)

Helicopter Electromagnetic Survey of the Model Land Area, Southeastern Miami-Dade County, Florida, Southeastern Miami-Dade County, Florida: U.S. Geological Survey Open-File Report 2012­1176, 77 p. Any use of Environmental Resources Management (Miami-Dade County, Florida) DOI depth of investigation DRG digital raster

162

MEASUREMENT AND ANALYSIS OF ELECTROMAGNETIC FIELDS FROM TRAMS, TRAINS AND HYBRID CARS  

E-Print Network (OSTI)

of electric and magnetic fields emitted from Australian trams, trains and hybrid cars were investigated cars are now electrically operated, therefore emitting less CO2 and less pollution into the environmentMEASUREMENT AND ANALYSIS OF ELECTROMAGNETIC FIELDS FROM TRAMS, TRAINS AND HYBRID CARS Malka N

Halgamuge, Malka N.

163

Electromagnetic plane waves with negative phase velocity in charged black strings  

SciTech Connect

We investigate the propagation regions of electromagnetic plane waves with negative phase velocity in the ergosphere of static charged black strings. For such a propagation, some conditions for negative phase velocity are established that depend on the metric components and the choice of the octant. We conclude that these conditions remain unaffected by the negative values of the cosmological constant.

Sharif, M., E-mail: msharif.math@pu.edu.pk; Manzoor, R., E-mail: rubabmanzoor9@yahoo.com [University of the Punjab, Department of Mathematics (Pakistan)

2013-02-15T23:59:59.000Z

164

Low frequency electrostatic and electromagnetic modes in nonuniform cold quantum plasmas  

SciTech Connect

The low frequency electrostatic and electromagnetic linear modes in a nonuniform cold quantum electron-ion plasma are studied. The effect of stationary dust on an electrostatic mode is also investigated. The quantum corrections in the linear dispersion relations of a cold dense plasma are presented with possible applications.

Saleem, H.; Ahmad, Ali [Theoretical Plasma Physics Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan); Khan, S. A. [Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan); Department of Physics, Government College Bagh AJK (Pakistan)

2008-01-15T23:59:59.000Z

165

Delta and Omega electromagnetic form factors in a Dyson-Schwinger/Bethe-Salpeter approach  

SciTech Connect

We investigate the electromagnetic form factors of the Delta and the Omega baryons within the Poincare-covariant framework of Dyson-Schwinger and Bethe-Salpeter equations. The three-quark core contributions of the form factors are evaluated by employing a quark-diquark approximation. We use a consistent setup for the quark-gluon dressing, the quark-quark bound-state kernel and the quark-photon interaction. Our predictions for the multipole form factors are compatible with available experimental data and quark-model estimates. The current-quark mass evolution of the static electromagnetic properties agrees with results provided by lattice calculations.

Diana Nicmorus, Gernot Eichmann, Reinhard Alkofer

2010-12-01T23:59:59.000Z

166

Self-focusing of intense high frequency electromagnetic waves in a collisional magnetoactive plasma  

Science Conference Proceedings (OSTI)

The self-focusing of an intense electromagnetic beam in a collisional magnetoactive plasma has been investigated by the perturbation method. Considering the relativistic and ponderomotive nonlinearities and the first three terms of perturbation expansion for the electron density and velocity, the nonlinear wave equation is obtained. This wave equation is solved by applying the source dependent expansion method and the evolution of electromagnetic beam spot-size is discussed. It is shown that the laser spot-size decreases with increasing the collision frequency and external magnetic field strength.

Niknam, A. R.; Hashemzadeh, M. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Evin, Tehran (Iran, Islamic Republic of); Aliakbari, A.; Majedi, S. [Physics Department, Faculty of Science, Tafresh University, Tafresh (Iran, Islamic Republic of); Haji Mirzaei, F. [Physics Department, Islamic Azad University, Arak Branch, Arak (Iran, Islamic Republic of)

2011-11-15T23:59:59.000Z

167

Category:Electromagnetic Profiling Techniques | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Category Edit History Facebook icon Twitter icon » Category:Electromagnetic Profiling Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Electromagnetic Profiling Techniques page? For detailed information on Electromagnetic Profiling Techniques, click here. Category:Electromagnetic Profiling Techniques Add.png Add a new Electromagnetic Profiling Techniques Technique Pages in category "Electromagnetic Profiling Techniques" This category contains only the following page. F Frequency-Domain Electromagnetic Survey Retrieved from "http://en.openei.org/w/index.php?title=Category:Electromagnetic_Profiling_Techniques&oldid=689835"

168

Phenomenological Model of Current Sheet Canting in Pulsed Electromagnetic Accelerators  

E-Print Network (OSTI)

Phenomenological Model of Current Sheet Canting in Pulsed Electromagnetic Accelerators T of current sheet canting in pulsed electromagnetic accelerators is the departure of the plasma sheet (that - canting angle [degrees] 5 - plasma frequency [rad/s] 1 Introduction Pulsed electromagnetic accelerators

Choueiri, Edgar

169

Measurements of current sheet canting in a pulsed electromagnetic accelerator  

E-Print Network (OSTI)

Measurements of current sheet canting in a pulsed electromagnetic accelerator T. E. Markusic, E. Y canting in pulsed electromagnetic accelerators is the departure of the plasma sheet (that carries in an experimental pulsed electromagnetic accelerator, using a variety of propellants and pressure levels

Choueiri, Edgar

170

Information Leakage via Electromagnetic Emanation and Effectiveness of Averaging Technique  

Science Conference Proceedings (OSTI)

It is well known that there is relationship between electromagnetic emanation and processing information in IT devices such as personal computers and smart cards. In this paper, we show how to estimate amount of information that is leaked as electromagnetic ... Keywords: Tempest, Channel capacity, electromagnetic emanation, averaging technique

Hidema Tanaka

2008-04-01T23:59:59.000Z

171

Electromagnetic Wellbore Heating Ibrahim Agyemang1  

E-Print Network (OSTI)

. temperature from the heat sources in any EMIT regions. Parts i) and ii) result in a second order ODE is inversely proportional to the velocity. Fluid that moves slowly past an EMIT region will absorb more heatChapter 5 Electromagnetic Wellbore Heating Ibrahim Agyemang1 , Matthew Bolton2 , Lloyd Bridge2

Bohun, C. Sean

172

A Simple Method for Generating Electromagnetic Oscillations  

E-Print Network (OSTI)

We propose a novel approach to the generation of electromagnetic oscillations by means of a low-frequency pumping of two coupled linear oscillators. A theory of such generation mechanism is proposed, and its feasibility is demonstrated by using coupled RLC oscillators. A comparison of the theoretical results and the experimental data is presented.

Vyacheslav Buts; Dmitriy Vavriv; Oleg Nechayev; Dmitriy Tarasov

2013-08-23T23:59:59.000Z

173

Electromagnetic Composites at the Compton Scale  

E-Print Network (OSTI)

A new class of electromagnetic composite particles is proposed. The composites are very small (the Compton scale), potentially long-lived, would have unique interactions with atomic and nuclear systems, and, if they exist, could explain a number of otherwise anomalous and conflicting observations in diverse research areas.

Frederick J. Mayer; John R. Reitz

2011-09-10T23:59:59.000Z

174

Build A Stronger Electromagnet Project Overview  

E-Print Network (OSTI)

this activity? 5. How did various sub-populations of students perform? Consider factors such as gender, race Electromagnet Sunshine State Standards Middle School: · The student recognizes that energy may be changed: · The student recognizes that energy may be changed in form with varying efficiency. (SC.B.1.4) · The student

Weston, Ken

175

Problems in electromagnetic mass-difference calculations  

SciTech Connect

A brief discussion is given on the progress made thus far in calculating the electromagnetic mass differences of elementary particles. Some of the methods discussed include Feynman's method, Cottinghams method, the methods involving Bjorken scaling iunctions, and the formalism of Dashen and Frautschi. (LBS)

Majumdar, D.P.

1972-01-01T23:59:59.000Z

176

Televisions, video privacy, and powerline electromagnetic interference  

Science Conference Proceedings (OSTI)

We conduct an extensive study of information leakage over the powerline infrastructure from eight televisions (TVs) spanning multiple makes, models, and underlying technologies. In addition to being of scientific interest, our findings contribute to ... Keywords: electromagnetic interference, information leakage, powerline security

Miro Enev; Sidhant Gupta; Tadayoshi Kohno; Shwetak N. Patel

2011-10-01T23:59:59.000Z

177

Definition: Time-Domain Electromagnetics | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Time-Domain Electromagnetics Jump to: navigation, search Dictionary.png Time-Domain Electromagnetics Time-domain electromagnetic (TDEM) surveys are active-source soundings which provide information about the electrical structure of the shallow subsurface.[1] View on Wikipedia Wikipedia Definition Transient electromagnetics, (also time-domain electromagnetics / TDEM), is a geophysical exploration technique in which electric and magnetic fields are induced by transient pulses of electric current and the subsequent decay response measured. TEM / TDEM methods are generally able to determine subsurface electrical properties, but are also sensitive to subsurface magnetic properties in applications like UXO detection and

178

Electromagnetic field radiation model for lightning strokes to tall structures  

SciTech Connect

This paper describes observation and analysis of electromagnetic field radiation from lightning strokes to tall structures. Electromagnetic field waveforms and current waveforms of lightning strokes to the CN Tower have been simultaneously measured since 1991. A new calculation model of electromagnetic field radiation is proposed. The proposed model consists of the lightning current propagation and distribution model and the electromagnetic field radiation model. Electromagnetic fields calculated by the proposed model, based on the observed lightning current at the CN Tower, agree well with the observed fields at 2km north of the tower.

Motoyama, H. [CRIEPI, Tokyo (Japan); Janischewskyj, W.; Hussein, A.M. [Univ. of Toronto, Ontario (Canada); Chisholm, W.A. [Ontario Hydro Technologies, Toronto, Ontario (Canada); Chang, J.S. [McMaster Univ., Hamilton, Ontario (Canada); Rusan, R.

1996-07-01T23:59:59.000Z

179

Analysis Of Factors Affecting Natural Source Slf Electromagnetic  

Open Energy Info (EERE)

Factors Affecting Natural Source Slf Electromagnetic Factors Affecting Natural Source Slf Electromagnetic Exploration At Geothermal Wells Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Analysis Of Factors Affecting Natural Source Slf Electromagnetic Exploration At Geothermal Wells Details Activities (0) Areas (0) Regions (0) Abstract: The Super Low Frequency (SLF) electromagnetic exploration was performed by using a nature source SLF electromagnetic detector at two geothermal wells in Peking University. The data of the SLF electromagnetic exploration at well JR-119 and JR-168 were obtained with the observation of continued five days and four times per day at well JR-119 and of one day at well JR-168. Based on these data, the influencing factors of the SI-F electromagnetic exploration were analyzed, which included the relationship

180

Coherent spin control by electromagnetic vacuum fluctuations  

SciTech Connect

In coherent control, electromagnetic vacuum fluctuations usually cause coherence loss through irreversible spontaneous emission. However, since the dissipation via emission is essentially due to correlation of the fluctuations, when emission ends in a superposition of multiple final states, correlation between different pathways may build up if the 'which way' information is not fully resolved (i.e., the emission spectrum is broader than the transition energy range). Such correlation can be exploited for spin-flip control in a {Lambda}-type three-level system, which manifests itself as an all-optical spin echo in nonlinear optics with two orders of optical fields saved as compared with stimulated Raman processes. This finding represents a class of optical nonlinearity induced by electromagnetic vacuum fluctuations.

Wang Jing [Department of Physics, Chinese University of Hong Kong, Shatin, N.T. (Hong Kong); Department of Physics, Tsinghua University, Beijing 100084 (China); Liu Renbao [Department of Physics, Chinese University of Hong Kong, Shatin, N.T. (Hong Kong); Zhu Bangfen [Department of Physics, Tsinghua University, Beijing 100084 (China); Institute of Advanced Study, Tsinghua University, Beijing 100084 (China); Sham, L. J. [Department of Physics, University of California-San Diego, La Jolla, California 92093-0319 (United States); Steel, D. G. [H. M. Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2011-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Electromagnetic radiation absorbers and modulators comprising polyaniline  

DOE Patents (OSTI)

A composition for absorbing electromagnetic radiation, wherein said electromagnetic radiation possesses a wavelength generally in the range of from about 1000 Angstroms to about 50 meters, wherein said composition comprises a polyaniline composition of the formula ##STR1## where y can be equal to or greater than zero, and R.sup.1 and R.sup.2 are independently selected from the group containing of H, --OCH.sub.3, --CH.sub.3, --F, --Cl, --Br, --I, NR.sup.3 .sub.2, --NHCOR.sup.3, --OH, --O.sup.-, SR.sup.3, --OCOR.sup.3, --NO.sub.2, --COOH, --COOR.sup.3, --COR.sup.3, --CHO, and --CN, where R.sup.3 is a C.sub.1 to C.sub.8 alkyl, aryl or aralkyl group.

Epstein, Arthur J. (Bexley, OH); Ginder, John M. (Columbus, OH); Roe, Mitchell G. (Columbus, OH); Hajiseyedjavadi, Hamid (Columbus, OH)

1992-01-01T23:59:59.000Z

182

Electromagnetically induced interference at superconducting qubits  

E-Print Network (OSTI)

We study electromagnetically induced interference at superconducting qubits. The interaction between qubits and electromagnetic fields can provide additional coupling channels to qubit states, leading to quantum interference in a microwave driven qubit. In particular, the interwell relaxation or Rabi oscillation, resulting respectively from the multi- or single-mode interaction, can induce effective crossovers. The environment is modeled by a multi-mode thermal bath, generating the interwell relaxation. Relaxation induced interference, independent of the tunnel coupling, provides deeper understanding to the interaction between the qubits and their environment. It also supplies a useful tool to characterize the relaxation strength as well as the characteristic frequency of the bath. In addition, we demonstrate the relaxation can generate population inversion in a strongly driving two-level system. On the other hand, different from Rabi oscillation, Rabi oscillation induced interference involves more complicate...

Du, Lingjie

2010-01-01T23:59:59.000Z

183

Fluidic electrodynamics: Approach to electromagnetic propulsion  

Science Conference Proceedings (OSTI)

We report on a new methodological approach to electrodynamics based on a fluidic viewpoint. We develop a systematic approach establishing analogies between physical magnitudes and isomorphism (structure-preserving mappings) between systems of equations. This methodological approach allows us to give a general expression for the hydromotive force, thus re-obtaining the Navier-Stokes equation departing from the appropriate electromotive force. From this ground we offer a fluidic approach to different kinds of issues with interest in propulsion, e.g., the force exerted by a charged particle on a body carrying current; the magnetic force between two parallel currents; the Magnus's force. It is shown how the intermingle between the fluid vector fields and electromagnetic fields leads to new insights on their dynamics. The new concepts introduced in this work suggest possible applications to electromagnetic (EM) propulsion devices and the mastery of the principles of producing electric fields of required configuration in plasma medium.

Martins, Alexandre A.; Pinheiro, Mario J. [Institute for Plasmas and Nuclear Fusion and Instituto Superior Tecnico Lisboa, Portugal 351.1.21.841.92.43 (Portugal); Department of Physics and Institute for Plasmas and Nuclear Fusion and Instituto Superior Tecnico Lisboa, Portugal 351.1.21.841.93.22 (Portugal)

2009-03-16T23:59:59.000Z

184

Electromagnetic Casimir Forces in Elliptic Cylinder Geometries  

E-Print Network (OSTI)

The scattering theory approach makes it possible to carry out exact calculations of Casimir energies in any geometry for which the scattering T-matrix and a partial wave expansion of the free Green's function are available. We implement this program for the case of a perfectly conducting elliptic cylinder, thereby completing the set of geometries where electromagnetic scattering is separable. Particular emphasis is placed on the case of zero radius, where the elliptic cylinder reduces to a strip.

Noah Graham

2013-03-26T23:59:59.000Z

185

Electromagnetic Interference Emission Measurements Near FACTS Devices  

Science Conference Proceedings (OSTI)

The expanded application of flexible AC transmission system (FACTS) technology to electric transmission and distribution systems frequently provides the best means of ensuring the needed levels of capacity and reliability. This final report provides a detailed look at the electromagnetic emissions from three tested FACTS systems. The report provides equipment immunity requirements from several potentially applicable standards, along with immunity data for nationwide differential global positioning system...

2003-03-11T23:59:59.000Z

186

Electromagnetic Interference Emission Measurements Near FACTS Devices  

Science Conference Proceedings (OSTI)

The expanded application of flexible AC transmission system (FACTS) technology to the electric transmission and distribution systems frequently provides the best means of insuring the needed levels of capacity and reliability. This interim report provides a detailed look at the electromagnetic emissions from the first two FACTS systems tested. Equipment immunity requirements from several potentially applicable standards are provided along with immunity data for nationwide differential global positioning ...

2002-12-13T23:59:59.000Z

187

Electromagnetic Modelling of Superconducting Sensor Designs  

E-Print Network (OSTI)

DEPARTMENT OF MATERIALS SCIENCE AND METALLURGY Electromagnetic Modelling of Superconducting Sensor Designs Guido Gerra Clare Hall, University of Cambridge 1 Preface The present dissertation has been submitted... and for all the moments they have shared with me. 4 Abstract The problem of design optimisation of thin film direct current Superconducting QUantum Interference Device (SQUID) magnetometers made of YBCO (YBa2Cu3O7-x) was considered. The inductances...

Gerra, Guido

188

Power System and Railroad Electromagnetic Compatibility Handbook  

Science Conference Proceedings (OSTI)

This book is a source of technology and data for preventing and mitigating ac electrical interference problems on railroads. All aspects of electromagnetic compatibility (EMC) where railroad systems are the receptors are examined. This includes well-understood areas such as magnetic induction from transmission lines as well as less understood areas such as conducted interference from distribution systems and effects of harmonics. Chapters examine all known effects of ac interference, including personnel ...

2006-11-29T23:59:59.000Z

189

Nonlinear fan instability of electromagnetic waves  

Science Conference Proceedings (OSTI)

This paper studies the linear and nonlinear stages of the fan instability, considering electromagnetic waves of the whistler frequency range interacting resonantly with energetic electron fluxes in magnetized plasmas. The main attention is paid to determine the wave-particle interaction processes that can lead to the excitation of intense electromagnetic waves by nonequilibrium particle distributions involving suprathermal tails, and to explain under what conditions and through what mechanisms they can occur, develop, and saturate. This paper presents and discusses two main processes: (i) the linear fan instability and (ii) the nonlinear process of dynamical resonance merging, which can significantly amplify the energy carried by linearly destabilized waves after they saturate due to particle trapping. This study consists of (i) determining analytically and numerically, for parameters typical of space and laboratory plasmas, the linear growth rates of whistlers excited by suprathermal particle fluxes through the fan instability, as well as the corresponding thresholds and the physical conditions at which the instability can appear, (ii) building a theoretical self-consistent 3D model and a related numerical code for describing the nonlinear evolution of the wave-particle system, and (iii) performing numerical simulations to reveal and characterize the nonlinear amplification process at work, its conditions of development, and its consequences, notably in terms of electromagnetic wave radiation. The simulations show that when the waves have reached sufficient energy levels owing to the linear fan instability, they saturate by trapping particles and due to the complex dynamics of these particles in the electromagnetic fields, the resonant velocities' domains of the waves overlap and merge, meanwhile a strong increase of the wave energy occurs.

Krafft, C. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, 91128 Palaiseau Cedex (France) and University Paris Sud, 91405 Orsay Cedex (France); Volokitin, A. [Space Research Institute (IKI), 117997, 84/32 Profsoyuznaya Str., Moscow (Russian Federation)

2010-10-15T23:59:59.000Z

190

Velocity damper for electromagnetically levitated materials  

DOE Patents (OSTI)

A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material. Two opposed field magnets are located orthogonally to the existing levitation coils for providing a DC quadrupole field (cusp field) around the material. The material used for generating the DC quadrupole field must be nonconducting to avoid eddy-current heating and of low magnetic permeability to avoid distorting the induction fields providing the levitation.

Fox, R.J.

1992-12-31T23:59:59.000Z

191

Velocity damper for electromagnetically levitated materials  

DOE Patents (OSTI)

A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material is disclosed. Two opposed field magnets are located orthogonally to the existing levitation coils for providing a DC quadrupole field (cusp field) around the material. The material used for generating the DC quadrupole field must be nonconducting to avoid eddy-current heating and of low magnetic permeability to avoid distorting the induction fields providing the levitation. 1 fig.

Fox, R.J.

1994-06-07T23:59:59.000Z

192

Investigation of efficiency optimization in free electron lasers  

SciTech Connect

The dynamics of trapped particles in the presence of the wiggler magnetic field and the electromagnetic radiation field in free electron lasers were investigated. From the results of computer simulations, it was found that, for a given set of parameters, the efficiency of energy extraction from the electron beam maximizes at a particular intensity of the electromagnetic radiation. Based on the physical argument of the dynamics of the trapped particles, a criterion which predicts accurately the optimum intensity of the electromagnetic radiation was obtained. (TFD)

Kwan, T.J.T.

1979-01-01T23:59:59.000Z

193

Particle production in strong electromagnetic fields in relativistic heavy-ion collisions  

E-Print Network (OSTI)

I review the origin and properties of electromagnetic fields produced in heavy ion collisions. The field strength immediately after a collision is proportional to the collision energy and reaches eB\\sim(m_\\pi)^2 at RHIC and eB\\sim10 (m_\\pi)^2 at LHC. I demonstrate by explicit analytical calculation that after dropping by about one-two orders of magnitude during the first fm/c of plasma expansion, it freezes out and lasts for as long as quark-gluon plasma exists as a consequence of finite electrical conductivity of the plasma. Magnetic field breaks spherical symmetry in the direction perpendicular to the reaction plane and therefore all kinetic coefficients are anisotropic. I examine viscosity of QGP and show that magnetic field induces azimuthal anisotropy on plasma flow even in spherically symmetric geometry. Very strong electromagnetic field has an important impact on particle production. I discuss the problem of energy loss and polarization of fast fermions due to synchrotron radiation, consider photon decay induced by magnetic field, elucidate J/Psi dissociation via Lorentz ionization mechanism and examine electromagnetic radiation by plasma. I conclude that all processes in QGP are affected by strong electromagnetic field and call for experimental investigation.

Kirill Tuchin

2013-01-01T23:59:59.000Z

194

Definition: Frequency-Domain Electromagnetic Survey | Open Energy  

Open Energy Info (EERE)

Electromagnetic Survey Electromagnetic Survey Jump to: navigation, search Dictionary.png Frequency-Domain Electromagnetic Survey Frequency-domain electromagnetic techniques are continuous wave field methods which enable the mapping of the electrical conductivity of the subsurface through electromagnetic induction.[1] Also Known As Controlled-Source EM References ↑ http://library.seg.org/doi/pdf/10.1190/1.1441531 Ret LikeLike UnlikeLike You like this.Sign Up to see what your friends like. rieved from "http://en.openei.org/w/index.php?title=Definition:Frequency-Domain_Electromagnetic_Survey&oldid=591411" Category: Definitions What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs Linked Data Developer services

195

Definition: Frequency-Domain Electromagnetics Survey | Open Energy  

Open Energy Info (EERE)

Frequency-Domain Electromagnetics Survey Frequency-Domain Electromagnetics Survey Jump to: navigation, search Dictionary.png Frequency-Domain Electromagnetics Survey Frequency-domain electromagnetic techniques are continuous wave field methods which enable the mapping of the electrical conductivity of the subsurface through electromagnetic induction.[1] View on Wikipedia Wikipedia Definition Electromagnetic induction is the production of a potential difference (voltage) across a conductor when it is exposed to a varying magnetic field. Michael Faraday is generally credited with the discovery of induction in 1831 though it may have been anticipated by the work of Francesco Zantedeschi in 1829. Around 1830 to 1832, Joseph Henry made a similar discovery, but did not publish his findings until later. Faraday's

196

Electromagnetic gearing applications in hybrid-electric vehicles  

E-Print Network (OSTI)

In this thesis, the operation of electric machines as three port devices is studied in detail. Electric machines used in this manner are referred to as electromagnetic gears in this research. All possible steady-state operating modes of these three-port devices have been explained in this thesis. Mathematical models for operating a switched reluctance machine and a separately excited dc machine as electromagnetic gears have been derived. These models have been used for simulating the performance of electromagnetic gears under various operating conditions. Electromagnetic gears can be used in hybrid electric propulsion systems as power sharing devices. This thesis explains the detailed operation of a new hybrid propulsion system utilizing electromagnetic gears. This propulsion system was proposed by Dr. M. Ehsani and has been named the "Transmotor Hybrid". The limitation of this propulsion system has also been explained in this thesis. The application of electromagnetic gears in hybrid propulsion systems has been described in detail in this research.

Sodhi, Sameer

1994-01-01T23:59:59.000Z

197

Generation of electro-magnetic oscillation in surface multijunction MOMOM  

Science Conference Proceedings (OSTI)

An intergrated surface multijunction MOMOM (metal-oxide-metal-oxide-metal) is reported and coherent electromagnetic oscillation is observed in the low frequency range.

Liao Shiqiang; Wang Yuzhu

1986-04-01T23:59:59.000Z

198

Analysis Of Factors Affecting Natural Source Slf Electromagnetic...  

Open Energy Info (EERE)

sensor orientation and the received artificial electromagnetic interference, influence of weather conditions on the data quality and so on. The results showed that (1) There is an...

199

Novel resonance-assisted electromagnetic-transport phenomena  

E-Print Network (OSTI)

We first demonstrate theoretically and experimentally that electromagnetic resonators with high quality factors (Q) can be used to transfer power efficiently over distances substantially larger than the characteristic ...

Kurs, Andr B

2011-01-01T23:59:59.000Z

200

Overview Of Electromagnetic Methods Applied In Active Volcanic...  

Open Energy Info (EERE)

in Colorado. For one example - Mt. Konocti in the Mayacamas Mountains, California - gravity, magnetic, and seismic, as well as electromagnetic methods have all been used in an...

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Time-Domain Electromagnetics At Long Valley Caldera Area (Sorey...  

Open Energy Info (EERE)

released results from 158 time-domain electromagnetic (TDEM) soundings and, with Chevron Resources, a total of 77 magnetotelluric (MT) stations. Reinterpretations of the...

202

Numerical Simulation of Electro-magnetic Turbulent Inhibitor ...  

Science Conference Proceedings (OSTI)

Numerical Modeling of Centrifugally Cast HSS Rolls Numerical Simulation of Electro-magnetic Turbulent Inhibitor Technology in a Tundish Optimizing the...

203

Effect of Electromagnetic Fields on the Filtration of Aluminium ...  

Science Conference Proceedings (OSTI)

Numerical Modeling of Centrifugally Cast HSS Rolls Numerical Simulation of Electro-magnetic Turbulent Inhibitor Technology in a Tundish Optimizing the...

204

Electromagnetic radiation from lightning return strokes to tall structures.  

E-Print Network (OSTI)

??The study of the interaction of lightning electromagnetic fields with electrical systems and the design of appropriate protection strategies are generally based on statistical distributions (more)

Pavanello, Davide

2007-01-01T23:59:59.000Z

205

Current Sheet Permeability in Electromagnetic Pulsed Plasma Thrusters  

E-Print Network (OSTI)

in Pulsed Electromagnetic Accelerators. PhD thesis, Princeton University, 2002. [6] R.G. Jahn and K.E. Clark

Choueiri, Edgar

206

Magnetohydrodynamic power generation, electromagnetic pumps, heat pipes, and thermionic convertors  

DOE Green Energy (OSTI)

The basic principles of operation, components, and design of MHD generators, electromagnetic pumps, heat pipes and thermionic converters are described. 66 references. (WHK)

Pierson, E.S.; Bonyhady, K.A.; Dunn, P.F.; Nathenson, R.D.; Uherka, K.L.

1984-01-01T23:59:59.000Z

207

A Numerical Evaluation Of Electromagnetic Methods In Geothermal...  

Open Energy Info (EERE)

GEOTHERMAL ENERGYGeothermal Home Journal Article: A Numerical Evaluation Of Electromagnetic Methods In Geothermal Exploration Details Activities (0) Areas (0) Regions (0) Abstract:...

208

6.013 Electromagnetics and Applications, Fall 2002  

E-Print Network (OSTI)

Electromagnetic phenomena are explored in modern applications including wireless communications, circuits, computer interconnects and peripherals, optical fiber links and components, microwave communications and radar, ...

Staelin, David H.

209

Why Study Electromagnetics: The First Unit in an Undergraduate Electromagnetics Course  

E-Print Network (OSTI)

integrate optical-fiber interconnects and optical microchips into systems of unimaginable information. Or could it? In fact, a simple Fourier analysis argument shows that recent optical systems that generate electromagnetic waves. For a foe determined to press an attack despite the operation of a radar system

Taflove, Allen

210

Geometric phases of the Faraday rotation of electromagnetic waves in magnetized plasmas  

Science Conference Proceedings (OSTI)

Geometric phases of circularly polarized electromagnetic waves in nonuniform magnetized plasmas is studied theoretically. The variation of the propagation direction of circularly polarized waves results in a geometric phase, which also contributes to the Faraday rotation, in addition to the standard dynamical phase. The origin and properties of the geometric phase are investigated. The influence of the geometric phase to plasma diagnostics using the Faraday rotation is discussed as an application of the theory.

Liu Jian [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Qin Hong [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

2012-10-15T23:59:59.000Z

211

From Electromagnetic Duality to Extended Electrodynamics  

E-Print Network (OSTI)

This paper presents the transition from Classical Electrodynamics (CED) to Extended Electrodynamics (EED) from the electromagnetic duality point of view, and emphasizes the role of the canonical complex structure in ${\\cal R}^2$ in, both, nonrelativistic and relativistic formulations of CED and EED. We begin with summarizing the motivations for passing to EED, as well as we motivate and outline the way to be followed in pursuing the right extension of Maxwell equations. Further we give the nonrelativistic and relativistic approaches to the extension and give explicitly the new equations as well as some properties of the nonlinear vacuum solutions.

Donev, S

2001-01-01T23:59:59.000Z

212

From Electromagnetic Duality to Extended Electrodynamics  

E-Print Network (OSTI)

This paper presents the transition from Classical Electrodynamics (CED) to Extended Electrodynamics (EED) from the electromagnetic duality point of view, and emphasizes the role of the canonical complex structure in ${\\cal R}^2$ in, both, nonrelativistic and relativistic formulations of CED and EED. We begin with summarizing the motivations for passing to EED, as well as we motivate and outline the way to be followed in pursuing the right extension of Maxwell equations. Further we give the nonrelativistic and relativistic approaches to the extension and give explicitly the new equations as well as some properties of the nonlinear vacuum solutions.

Stoil Donev

2001-01-20T23:59:59.000Z

213

Survey of nucleon electromagnetic form factors  

Science Conference Proceedings (OSTI)

There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has been greatly improved by performing double polarization experiments, in compar- ison with previous unpolarized data. Here we review the experimental data base in view of the new results for the proton, and neutron, obtained at MIT-Bates, MAMI, and JLab. The rapid evolution of phenomenological models triggered by these high-precision experiments will be discussed.

Perdrisat, Charles F. [William and Mary College; Punjabi, Vina A. [Norfolk State U.

2011-09-20T23:59:59.000Z

214

Physics with the ALICE Electromagnetic Calorimeter  

E-Print Network (OSTI)

I will present physics measurements which are achievable in the ALICE experiment at the LHC through the inclusion of a new electromagnetic calorimeter. I will focus on jet measurements in proton proton and heavy ion collisions. Detailed simulations have been performed on jet reconstruction, jet triggering, heavy flavor jet reconstruction through electron identification, gamma-jet reconstruction and the measurements of identified hadrons and resonances in jets. I will show the physics capabilities which are made possible through the combination of calorimeter information with the other detector components in ALICE.

Rene Bellwied; for the ALICE Collaboration

2009-07-17T23:59:59.000Z

215

Electromagnetic wave scattering by many small particles  

E-Print Network (OSTI)

Scattering of electromagnetic waves by many small particles of arbitrary shapes is reduced rigorously to solving linear algebraic system of equations bypassing the usual usage of integral equations. The matrix elements of this linear algebraic system have physical meaning. They are expressed in terms of the electric and magnetic polarizability tensors. Analytical formulas are given for calculation of these tensors with any desired accuracy for homogeneous bodies of arbitrary shapes. An idea to create a "smart" material by embedding many small particles in a given region is formulated.

A. G. Ramm

2006-08-11T23:59:59.000Z

216

Photographic, magnetic, and interferometric measurements of current sheet canting in a pulsed electromagnetic accelerator  

E-Print Network (OSTI)

in a pulsed electromagnetic accelerator were measured using three different techniques: high- speed at higher pressures. 1 Introduction Pulsed electromagnetic accelerators are devices which use intense bursts Apparatus An experimental pulsed electromagnetic accelerator has been constructed. The accelerator

Choueiri, Edgar

217

Non-minimal $R^\\beta F^2$-Coupled Electromagnetic Fields to Gravity and Static, Spherically Symmetric Solutions  

E-Print Network (OSTI)

We investigate non-minimal $R^\\beta F^2$-type couplings of electromagnetic fields to gravity. We derive the field equations by a first order variational principle using the method of Lagrange multipliers. Then we present various static, spherically symmetric solutions describing the exterior fields in the vicinity of electrically charged massive bodies.

Dereli, Tekin

2011-01-01T23:59:59.000Z

218

Steven Weinberg, Weak Interactions, and Electromagnetic Interactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Steven Weinberg and Steven Weinberg and Weak and Electromagnetic Interactions Resources with Additional Information Steven Weinberg Courtesy Dr. Steven Weinberg Steven "Weinberg is a professor of physics and astronomy at UT [The University of Texas] Austin and is founding director of the Theory Group in the College of Natural Sciences. [He is] well known for his development of a field theory that unifies the electromagnetic and weak nuclear forces, and for other major contributions to physics and cosmology ... Weinberg's work has been honored with numerous prizes, including the Nobel Prize in Physics in 1979 and the National Medal of Science in 1991. Weinberg is the author of the prize-winning book The First Three Minutes: A Modern View of the Origin of the Universe (which has been translated into 22 foreign languages) as well as Gravitation and Cosmology, The Discovery of Subatomic Particles, Dreams of a Final Theory and The Quantum Theory of Fields. ... Weinberg was the recipient of the Scientist as Poet prize from Rockefeller University for "extraordinary achievements in conveying - with passionate clarity - the ideas, history, explanatory power and aesthetic dimensions of fundamental physics." The citation mentioned two of Weinberg's books.

219

Electromagnetically induced interference at superconducting qubits  

E-Print Network (OSTI)

We study electromagnetically induced interference at superconducting qubits. The interaction between qubits and electromagnetic fields can provide additional coupling channels to qubit states, leading to quantum interference in a microwave driven qubit. In particular, the interwell relaxation or Rabi oscillation, resulting respectively from the multi- or single-mode interaction, can induce effective crossovers. The environment is modeled by a multi-mode thermal bath, generating the interwell relaxation. Relaxation induced interference, independent of the tunnel coupling, provides deeper understanding to the interaction between the qubits and their environment. It also supplies a useful tool to characterize the relaxation strength as well as the characteristic frequency of the bath. In addition, we demonstrate the relaxation can generate population inversion in a strongly driving two-level system. On the other hand, different from Rabi oscillation, Rabi oscillation induced interference involves more complicated and modulated photon exchange thus offers an alternative means to manipulate the qubit, with more controllable parameters including the strength and position of the tunnel coupling. It also provides a testing ground for exploring nonlinear quantum phenomena and quantum state manipulation, in not only the flux qubit but also the systems with no crossover structure, e.g. phase qubits.

Lingjie Du; Yang Yu

2010-12-14T23:59:59.000Z

220

Electromagnetic fields: Biological and clinical aspects  

SciTech Connect

Our entire biosphere is immersed in a sea of man-made electromagnetic fields (EMF). Occupational and public health data suggest that these fields may be a health hazard, possibly involving cancer and fetal loss. This paper reviews the history and pertinent physics of electromagnetic fields and presents evidence from the authors' work, and that of others, of biological interaction with living systems. Epidemiological data suggesting EMF hazards are reviewed including a discussion of possible risks associated with Hawaii's Lualualei transmitter site, TV and FM antennas in high-density population areas, fields surrounding electric power transmission and computer terminals, and the plan to route a major highway through the near-field of an operating Omega signal-source. In the face of current public fear and controversial research reports about long-term EMF exposure, suggestions are presented for public policy about these local sources of concern, as well as for the EMF risks common to any similarly developed areas. 30 refs.

Tabrah, F.L.; Batkin, S. (Department of Physiology, University of Hawaii School of Medicine, Honolulu (USA))

1991-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Electromagnetic Wellbore Heating C. Sean Bohun, The Pennsylvania State University,  

E-Print Network (OSTI)

the heat sources in any EMIT regions and how this couples to part i) and ii). Parts i) and ii) resultElectromagnetic Wellbore Heating C. Sean Bohun, The Pennsylvania State University, Bruce McGee, Mc of petroleum fluids from an oil reservoir by the method of electromagnetic heating. By its very nature

Bohun, C. Sean

222

An electromagnetism metaheuristic for solving the Maximum Betweenness Problem  

Science Conference Proceedings (OSTI)

In this paper we present an electromagnetism (EM) metaheuristic for solving NP hard Maximum Betweenness Problem (MBP). A new encoding scheme with appropriate objective functions is implemented. Specific representation of the individuals enables the EM ... Keywords: Betweenness problem, Combinatorial optimization, Electromagnetism-like mechanism

Vladimir Filipovi?; Aleksandar Kartelj; Dragan Mati?

2013-02-01T23:59:59.000Z

223

Electromagnetic Buckled Beam Oscillator for Enhanced Vibration Energy Harvesting  

Science Conference Proceedings (OSTI)

In this work, a nonlinear vibration energy harvester consisting of a buckled beam and an electromagnetic transducer is proposed. An advantage of this device is that there is no need of permanent magnets to create the bistable potential. Theoretical modeling ... Keywords: Vibration energy harvester (VEH), non linear system, bistability, Duffing oscillator, electromagnetic generators (EMG)

F. Cottone, P. Basset, H. Vocca, L. Gammaitoni

2012-11-01T23:59:59.000Z

224

Electromagnetic torque analysis of a DFIG for wind turbines  

Science Conference Proceedings (OSTI)

Electromagnetic torque of doubly fed induction generator (DFIG) is a consequence of the rotor and stator supply. The stator voltage has a fixed amount and frequency. The rotor voltage of the DFIG as a part of a wind turbine has a variable amount and ... Keywords: DFIG, electromagnetic torque, renewable energy, wind turbine

Jurica Smajo; Dinko Vukadinovic

2008-05-01T23:59:59.000Z

225

Schlieren Techniques for the Visualization of Current Sheets in Pulsed Electromagnetic Accelerators  

E-Print Network (OSTI)

Schlieren Techniques for the Visualization of Current Sheets in Pulsed Electromagnetic Accelerators in the initi- ation, propagation, and ejection of current sheets in pulsed electromagnetic accelerators

Choueiri, Edgar

226

Airborne Electromagnetic Survey At Raft River Geothermal Area (1979) | Open  

Open Energy Info (EERE)

Electromagnetic Survey At Raft River Electromagnetic Survey At Raft River Geothermal Area (1979) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Airborne Electromagnetic Survey Activity Date 1979 Usefulness not indicated DOE-funding Unknown Exploration Basis To show that AEM methods can be useful in exploration for and defining geothermal systems Notes Extensive audio-magnetotelluric (AMT) work by the USGS in KGRA's showed that many geothermal systems do have a near-surface electrical signature which should be detectable by an AEM system. References Christopherson, K.R.; Long, C.L.; Hoover, D.B. (1 September 1980) Airborne electromagnetic surveys as a reconnaissance technique for geothermal exploration Retrieved from "http://en.openei.org/w/index.php?title=Airborne_Electromagnetic_Survey_At_Raft_River_Geothermal_Area_(1979)&oldid=510231

227

Electromagnetic field of a charge intersecting a cold plasma boundary in a waveguide  

SciTech Connect

We analyze the electromagnetic field of a charge crossing a boundary between a vacuum and cold plasma in a waveguide. We obtain exact expressions for the field components and the spectral density of the transition radiation. With the steepest descent technique, we investigate the field components. We show that the electromagnetic field has a different structure in a vacuum than in cold plasma. We also develop an algorithm for the computation of the field based on a certain transformation of the integration path. The behavior of the field depending on distance and time and the spectral density depending on frequency are explored for different charge velocities. Some important physical effects are noted. A considerable increase and concentration of the field near the wave front in the plasma is observed for the case of ultrarelativistic particles. In the plasma, the mode envelopes and spectral density show zero points when the charge velocity is within certain limits.

Alekhina, Tatiana Yu.; Tyukhtin, Andrey V. [Radiophysics Department of St. Petersburg University, 1 Ulyanovskaya, St. Petersburg 198504 (Russian Federation)

2011-06-15T23:59:59.000Z

228

Low frequency electromagnetic oscillations in dense degenerate electron-positron pair plasma, with and without ions  

SciTech Connect

Quantum plasma oscillations are studied in a strongly magnetized, ultra-dense plasma with degenerate electrons and positrons. The dispersive role of electron and positron quantum effects on low frequency (in comparison to electron cyclotron frequency) shear electromagnetic wave is investigated by employing hydrodynamic formulation. In the presence of ions, the density balance changes, and the electromagnetic wave (with frequency lower than the ion cyclotron frequency) is shown to couple with electrostatic ion mode under certain conditions. For such low frequency waves, it is also seen that the contribution of electron and positron degeneracy pressure is dominant as compared to their diffraction effects. The results are analyzed numerically for illustrative purpose pointing out their relevance to the dense laboratory (e.g., super-intense laser-dense matter interactions) and astrophysical plasmas.

Khan, S. A. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Ayub, M. K. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Pohang University of Science and Technology (POSTECH), Pohang, Gyunbuk 790-784 (Korea, Republic of); Ahmad, Ali [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000 (Pakistan)

2012-10-15T23:59:59.000Z

229

A quaternionic unification of electromagnetism and hydrodynamics  

E-Print Network (OSTI)

We have derived energy conservation equations from the quaternionic Newton's law that is compatible with Lorentz transformation. This Newton's law yields directly the Euler equation and other relations governing the fluid motion. With this formalism, the pressure contributes positively to the dynamics of the system in the same way mass does. Hydrodynamic equations are derived from Maxwell's equations by adopting an electromagnetohydrodynamics analogy. In this analogy the hydroelectric field is related to the local acceleration of the fluid and the Lorentz gauge is related to the incompressible fluid condition. An analogous Lorentz gauge in hydrodynamics is proposed. We have shown that the vorticity of the fluid is developed whenever the particle local acceleration of the fluid deviates from the velocity direction. We have shown that Lorentz force in electromagnetism corresponds to Euler force for fluids. Moreover, we have obtained a Faraday-like law and Ampere's -like law in Hydrodynamics.

Arbab, Arbab I

2010-01-01T23:59:59.000Z

230

Concerning Measurement of Gravitomagnetism in Electromagnetic Systems  

E-Print Network (OSTI)

Measurement of gravitomagnetic field is of fundamental importance as a test of general relativity. Here we present a new theoretical project for performing such a measurement based on detection of the electric field arising from the interplay between the gravitomagnetic and magnetic fields in the stationary axial-symmetric gravitational field of a slowly rotating massive body. Finally it is shown that precise magnetometers based on superconducting quantum interferometers could not be designed for measurement of the gravitomagnetically induced magnetic field in the cavity of a charged capacitor since they measure the circulation of a vector potential of electromagnetic field, i.e., an invariant quantity including the sum of electric and magnetic fields, and the general-relativistic magnetic part will be totally cancelled by the electric one which is in good agreement with the experimental results.

B. J. Ahmedov; N. I. Rakhmatov

2006-08-07T23:59:59.000Z

231

A quaternionic unification of electromagnetism and hydrodynamics  

E-Print Network (OSTI)

We have derived energy conservation equations from the quaternionic Newton's law that is compatible with Lorentz transformation. This Newton's law yields directly the Euler equation and other equations governing the fluid motion. With this formalism, the pressure contributes positively to the dynamics of the system in the same way mass does. Hydrodynamic equations are derived from Maxwell's equations by adopting an electromagnetohydrodynamics (EMH) analogy. In this analogy the hydroelectric field is related to the local acceleration of the fluid and the Lorentz gauge is related to the incompressible fluid condition. An analogous Lorentz gauge in hydrodynamics is proposed. We have shown that the vorticity of the fluid is developed whenever the particle local acceleration of the fluid deviates from the velocity direction. We have also shown that Lorentz force in electromagnetism corresponds to Euler force in fluids. Moreover, we have obtained Gauss's, Faraday's and Ampere's -like laws in Hydrodynamics.

Arbab I. Arbab

2010-02-27T23:59:59.000Z

232

Detection of electromagnetic waves using charged MEMS structures  

SciTech Connect

We describe micromechanical structures that are capable of sensing both electrostatic fields and electromagnetic fields over a wide frequency range. Typically, sensing of electromagnetic waves is achieved with electrically conducting antennas, which despite the many advantages do not exhibit high sensitivity over a broad frequency range. An important aspect of our present work is that, in contrast to traditional antennas, the dimensions of micromechanical oscillators sensitive to electromagnetic waves can be much smaller than the wavelength. We characterized the micromechanical oscillators and measured responses to electric fields and estimated the performance limits by evaluating the signal-to-noise ratio theoretically and experimentally.

Datskos, Panos G [ORNL; Lavrik, Nickolay V [ORNL; Tobin, Jacob D [ORNL; Bowland, Landon T [ORNL

2012-01-01T23:59:59.000Z

233

Nonlinear Landau damping of transverse electromagnetic waves in dusty plasmas  

SciTech Connect

High-frequency transverse electromagnetic waves in a collisionless isotropic dusty plasma damp via nonlinear Landau damping. Taking into account the latter we have obtained a generalized set of Zakharov equations with local and nonlocal terms. Then from this coupled set of Zakharov equations a kinetic nonlinear Schroedinger equation with local and nonlocal nonlinearities is derived for special cases. It is shown that the modulation of the amplitude of the electromagnetic waves leads to the modulation instability through the nonlinear Landau damping term. The maximum growth rate is obtained for the special case when the group velocity of electromagnetic waves is close to the dust acoustic velocity.

Tsintsadze, N. L. [E. Andronikashvili Institute of Physics, Tbilisi 0171 (Georgia); Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Chaudhary, Rozina [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Shah, H. A. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan)

2009-04-15T23:59:59.000Z

234

The electromagnetic calorimeter for the STAR experiment at RHIC  

SciTech Connect

The STAR detector at RHIC can be used both for searches for quark-gluon plasma and for high energy pp spin physics. An electromagnetic calorimeter is being planned which will be used for triggering on High pt direct gammas, e{sup {plus_minus}}, and the electromagnetic component of jets. Jets will be measured for both kinds of physics by using the electro-magnetic calorimeter and central TPC tracking. We describe some features of the fiber-tile calorimeter as it is presently being designed.

Underwood, D.G.

1992-11-01T23:59:59.000Z

235

3DEMIII Workshop, February 2003, Adelaide. Efficient 3-D Electromagnetic Modeling in the Presence of  

E-Print Network (OSTI)

;Electromagnetic Laboratory, Department of Eletrical and Computer Engineering, University of Illinois, Urbana, IL

Torres-Verdín, Carlos

236

Electromagnetic Interference Between Different Model Wireless Communications Devices and Electronic Medical Equipment  

Science Conference Proceedings (OSTI)

This case study describes instances of incompatibility between sensitive electronic medical equipment and its electromagnetic environment.

2003-12-31T23:59:59.000Z

237

Standard Test Method for Determining Electrical Conductivity Using the Electromagnetic (Eddy-Current) Method  

E-Print Network (OSTI)

Standard Test Method for Determining Electrical Conductivity Using the Electromagnetic (Eddy-Current) Method

American Society for Testing and Materials. Philadelphia

2009-01-01T23:59:59.000Z

238

Standard Practice for Electromagnetic (Eddy-Current) Examination of Copper Redraw Rod for Electrical Purposes  

E-Print Network (OSTI)

Standard Practice for Electromagnetic (Eddy-Current) Examination of Copper Redraw Rod for Electrical Purposes

American Society for Testing and Materials. Philadelphia

2009-01-01T23:59:59.000Z

239

Airborne electromagnetic surveys as a reconnaissance technique for  

Open Energy Info (EERE)

electromagnetic surveys as a reconnaissance technique for electromagnetic surveys as a reconnaissance technique for geothermal exploration Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Airborne electromagnetic surveys as a reconnaissance technique for geothermal exploration Details Activities (1) Areas (1) Regions (0) Abstract: INPUT airborne electromagnetic (AEM) surveys were conducted during 1979 in five Known Geothermal Resource Areas (KGRA's). AEM work has not been significantly utilized in the past for geothermal purposes because it was thought that a shallow exploration technique would not be effective. Extensive audio-magnetotelluric (AMT) work by the USGS in KGRA's showed that many geothermal systems do have a near-surface electrical signature which should be detectable by an AEM system. INPUT responses in the form of

240

Electromagnetic Soundings At Raft River Geothermal Area (1977) | Open  

Open Energy Info (EERE)

Electromagnetic Soundings At Raft River Geothermal Area (1977) Electromagnetic Soundings At Raft River Geothermal Area (1977) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Electromagnetic Soundings At Raft River Geothermal Area (1977) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Electromagnetic Sounding Techniques Activity Date 1977 Usefulness not indicated DOE-funding Unknown Exploration Basis The purpose of the survey was: (1) to field test U.S. Geological Survey extra-low-frequency (ELF) equipment using a grounded wire source and receiver loop configuration (which is designed to measure the vertical magnetic field (Hz) at the loop center for various frequencies); (2) to present an example of the EM sounding data and interpretations using a

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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241

Time-Domain Electromagnetics At Haleakala Volcano Area (Thomas, 1986) |  

Open Energy Info (EERE)

Time-Domain Electromagnetics At Haleakala Volcano Time-Domain Electromagnetics At Haleakala Volcano Area (Thomas, 1986) Exploration Activity Details Location Haleakala Volcano Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes Controlled-source electromagnetic soundings were found to be substantially more successful in the southwest rift than either the Schlumberger or the self-potential studies. This was largely due to the ability of time-domain methods to penetrate high-resistivity surface layers and thus to define lower-resistivity sections at depth. The results of this sounding study, which was conducted at elevations ranging from 75 to 497 m a.s.l., generally indicated moderate- to lowresistivity (6 - 7 ohm.m) sections to depths of 1 km on the lower rift zone and higher resistivities (12-16

242

A Numerical Evaluation Of Electromagnetic Methods In Geothermal Exploration  

Open Energy Info (EERE)

Evaluation Of Electromagnetic Methods In Geothermal Exploration Evaluation Of Electromagnetic Methods In Geothermal Exploration - L Pellerin, J M Johnston & G W Hohmann, Geophysics, 61(1), 1996, Pp 121-130 Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Numerical Evaluation Of Electromagnetic Methods In Geothermal Exploration - L Pellerin, J M Johnston & G W Hohmann, Geophysics, 61(1), 1996, Pp 121-130 Details Activities (0) Areas (0) Regions (0) Abstract: Unavailable Author(s): Unknown Published: International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1996 Document Number: Unavailable DOI: 10.1016/S0148-9062(97)87449-9 Source: View Original Journal Article Retrieved from "http://en.openei.org/w/index.php?title=A_Numerical_Evaluation_Of_Electromagnetic_Methods_In_Geothermal_Exploration_-_L_Pellerin,_J_M_Johnston_%26_G_W_Hohmann,_Geophysics,_61(1),_1996,_Pp_121-130&oldid=3883

243

Frequency-Domain Electromagnetic Survey | Open Energy Information  

Open Energy Info (EERE)

Frequency-Domain Electromagnetic Survey Frequency-Domain Electromagnetic Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Frequency-Domain Electromagnetic Survey Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Profiling Techniques Information Provided by Technique Lithology: Detection of high-conductivity bodies in the subsurface. Stratigraphic/Structural: Hydrological: Thermal: Detection of the presence of a thermal anomaly through its resistivity signature. Cost Information Low-End Estimate (USD): 2,928.38292,838 centUSD 2.928 kUSD 0.00293 MUSD 2.92838e-6 TUSD / mile Median Estimate (USD): 4,505.20450,520 centUSD

244

Interpretation of electromagnetic soundings in the Raft River geothermal  

Open Energy Info (EERE)

Interpretation of electromagnetic soundings in the Raft River geothermal Interpretation of electromagnetic soundings in the Raft River geothermal area, Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Interpretation of electromagnetic soundings in the Raft River geothermal area, Idaho Details Activities (1) Areas (1) Regions (0) Abstract: An electromagnetic (EM) controlled source survey was conducted in the Raft River Valley, near Malta, Idaho. The purpose of the survey was: to field test U.S. Geological Survey extra-low-frequency (ELF) equipment using a grounded wire source and receiver loop configuration (which is designed to measure the vertical magnetic field (Hz) at the loop center for various frequencies); to present an example of the EM sounding data and interpretations using a previously developed inversion program; and (3) to

245

Dispersion relation of electromagnetic ion cyclotron waves using Cluster observations  

E-Print Network (OSTI)

Multi-point wave observations on Cluster spacecraft are used to infer the dispersion relation of electromagnetic ion cyclotron (EMIC) waves. In this study we use a phase differencing method and observations from STAFF and ...

Pakhotin, I. P.

246

Design and parametric simulation of radially oriented electromagnetic actuators  

E-Print Network (OSTI)

This thesis presents the design and simulation of an electromagnetic actuator system capable of delivering large pulses of radial force onto a cylindrical surface. Due to its robust design, simple control scheme, and large ...

Bosworth, William R., S.M. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

247

Low-cost electromagnetic tagging : design and implementation  

E-Print Network (OSTI)

Several implementations of chipless RFID (Radio Frequency Identification) tags are presented and discussed as low-cost alternatives to chip-based RFID tags and sensors. An overview of present-day near-field electromagnetic ...

Fletcher, Richard R. (Richard Ribon)

2002-01-01T23:59:59.000Z

248

Compromising electromagnetic emanations of wired and wireless keyboards  

Science Conference Proceedings (OSTI)

Computer keyboards are often used to transmit confidential data such as passwords. Since they contain electronic components, keyboards eventually emit electromagnetic waves. These emanations could reveal sensitive information such as keystrokes. The ...

Martin Vuagnoux; Sylvain Pasini

2009-08-01T23:59:59.000Z

249

Interaction of High Intensity Electromagnetic Waves with Plasmas  

SciTech Connect

The focus of our work during the duration of this grant was on the following areas: (a) the fundamental plasma physics of intense laser-plasma interactions, including the nonlinear excitation of plasma waves for accelerator applications, as well as the recently discovered by us phenomenon of the relativistic bi-stability of relativistic plasma waves driven by a laser beatwave; (b) interaction of high power microwave beams with magnetized plasma, including some of the recently discovered by us phenomena such as the Undulator Induced Transparency (UIT) as well as the new approaches to dynamic manipulation of microwave pulses; (c) investigations of the multi-color laser pulse interactions in the plasma, including the recently discovered by us phenomenon of Electromagnetic Cascading (EC) and the effect of the EC of three-dimensional dynamics of laser pulses (enhanced/suppressed selffocusing etc.); (d) interaction of high-current electron beams with the ambient plasma in the context of Fast Ignitor (FI) physics, with the emphasis on the nonlinear dynamics of the Weibel instability and beam filamentation.

G. Shvets

2008-10-03T23:59:59.000Z

250

Guidelines for Electromagnetic Interference Testing in Power Plants: Revision 1  

Science Conference Proceedings (OSTI)

Concern about the effect of electromagnetic emissions on the safe, reliable operation of digital equipment has resulted in requirements for utilities to create detailed emissions maps. This guide identifies emissions sources in nuclear power plants, recommends susceptibility and emissions standards, and details design and layout practices for minimizing susceptibility to electromagnetic interference (EMI). Revision 1 reflects modifications to the original document, which received NRC approval in a Safety...

1997-04-16T23:59:59.000Z

251

The Covariant Electromagnetic Casimir Effect for Real Conducting Cylindrical Shells  

E-Print Network (OSTI)

Using covariant quantization of the electromagnetic field, the Casimir force per unit area experienced by a long conducting cylindrical shell, under both Dirichlet and Neumann boundary conditions, is calculated. The renormalization procedure is based on the plasma cut-off frequency for real conductors. The real case of a gold (silver) cylindrical shell is considered and the corresponding electromagnetic Casimir pressure is computed. It is discussed that the Dirichlet and Neumann problems should be considered separately without adding their corresponding results.

H. Razmi; N. Fadaei

2013-07-31T23:59:59.000Z

252

Guidelines for Electromagnetic Compatibility Testing of Power Plant Equipment  

Science Conference Proceedings (OSTI)

To continue meeting safety and reliability requirements while controlling costs, operators of nuclear power plants must be able to replace and upgrade equipment in a cost-effective manner. One issue that has been problematic for new plant equipment and especially for digital instrumentation and control (I&C) systems in recent years is electromagnetic compatibility (EMC). The EMC issue usually involves testing to show that critical equipment will not be adversely affected by electromagnetic ...

2013-12-08T23:59:59.000Z

253

Effects of Electromagnetic Fields on Fish and Invertebrates  

Science Conference Proceedings (OSTI)

In this progress report, we describe the preliminary experiments conducted with three fish and one invertebrate species to determine the effects of exposure to electromagnetic fields. During fiscal year 2010, experiments were conducted with coho salmon (Onchrohychus kisutch), California halibut (Paralicthys californicus), Atlantic halibut (Hippoglossus hippoglossus), and Dungeness crab (Cancer magister). The work described supports Task 2.1.3: Effects on Aquatic Organisms, Subtask 2.1.3.1: Electromagnetic Fields.

Schultz, Irvin R.; Woodruff, Dana L.; Marshall, Kathryn E.; Pratt, William J.; Roesijadi, Guritno

2010-10-13T23:59:59.000Z

254

The underground electromagnetic pulse: Four representative models  

Science Conference Proceedings (OSTI)

I describe four phenomenological models by which an underground nuclear explosion may generate electromagnetic pulses: Compton current asymmetry (or ''Compton dipole''); Uphole conductor currents (or ''casing currents''); Diamagnetic cavity plasma (or ''magnetic bubble''); and Large-scale ground motion (or ''magneto-acoustic wave''). I outline the corresponding analytic exercises and summarize the principal results of the computations. I used a 10-kt contained explosion as the fiducial case. Each analytic sequence developed an equivalent source dipole and calculated signal waveforms at representative ground-surface locations. As a comparative summary, the Compton dipole generates a peak source current moment of about 12,000 A/center dot/m in the submicrosecond time domain. The casing-current source model obtains an equivalent peak moment of about 2 /times/ 10/sup 5/ A/center dot/m in the 10- to 30-/mu/s domain. The magnetic bubble produces a magnetic dipole moment of about 7 /times/ 10/sup 6/ A/center dot/m/sup 2/, characterized by a 30-ms time structure. Finally, the magneto-acoustic wave corresponds to a magnetic dipole moment of about 600 A/center dot/m/sup 2/, with a waveform showing 0.5-s periodicities. 8 refs., 35 figs., 7 tabs.

Wouters, L.F.

1989-06-01T23:59:59.000Z

255

Binary power multiplier for electromagnetic energy  

DOE Patents (OSTI)

A technique for converting electromagnetic pulses to higher power amplitude and shorter duration, in binary multiples, splits an input pulse into two channels, and subjects the pulses in the two channels to a number of binary pulse compression operations. Each pulse compression operation entails combining the pulses in both input channels and selectively steering the combined power to one output channel during the leading half of the pulses and to the other output channel during the trailing half of the pulses, and then delaying the pulse in the first output channel by an amount equal to half the initial pulse duration. Apparatus for carrying out each of the binary multiplication operation preferably includes a four-port coupler (such as a 3 dB hybrid), which operates on power inputs at a pair of input ports by directing the combined power to either of a pair of output ports, depending on the relative phase of the inputs. Therefore, by appropriately phase coding the pulses prior to any of the pulse compression stages, the entire pulse compression (with associated binary power multiplication) can be carried out solely with passive elements.

Farkas, Zoltan D. (203 Leland Ave., Menlo Park, CA 94025)

1988-01-01T23:59:59.000Z

256

Pulsed electromagnetic acceleration of exploded wire plasmas  

Science Conference Proceedings (OSTI)

A simple analysis of the dynamic state of a current-conducting high-density plasma column, resulting from an exploded wire between the conductors of a rail-gun accelerator or one or more wires strung between the anode and cathode conductors in a pulsed-power generator diode, is given on the basis of a one-dimensional magnetohydrodynamics model. Spatial distributions of the current density, magnetic field, temperature, and particle density are calculated as well as the temporal current, voltage, and impedance histories. The model self-consistently treats the accelerator load transition through its solid, melt, vapor, and plasma states in the presence of its supply source and feed network. Once formed and accelerated, the plasma state calculations show expansion cooling across the self-induced magnetic field if the Bennett condition is not satisfied. The model predictions are compared to two experimental situations. The first involves the delivery of some hundreds of Joules of stored energy to the wire load. For this case, good agreement between the calculated and observed plasma state is obtained. The second situation involves the delivery of many thousands of Joules to the wire load. For this case and dependent upon the wire mass, diameter, number of wires exploded, their separation, and the pulsed energy electrical wave shapes, the magnetohydrodynamic results can be qualitatively incorrect. The necessity of an electromagnetic particle simulation approach is indicated in order to resolve the magnetic rope-like structure and filamentation observed in the very energetic plasmas.

Peratt, A.L.; Koert, P.

1983-11-01T23:59:59.000Z

257

Nucleon Structure Studies with Electromagnetic Probes  

Science Conference Proceedings (OSTI)

Summarized in this report is the progress achieved during the period from March 1, 2008 to June 14, 2009 under contract number DE-FG02-03ER41252. This is the final technical report under this contract. The experimental work described here is part of the electromagnetic nuclear physics program of the CEBAF Large Acceptance Spectrometer (CLAS) Collaboration at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) that published 17 journal articles during the period of this report. One of these journal articles reported on the results of precise measurements of the neutron magnetic form factor. I was a spokesperson on this experiment and the publication of these results is the culmination of years of effort by a small subset of the CLAS Collaboration. As usual, undergraduate students were involved in all aspects of this work. Three Union College students participated in this program during the window of this report and one presented a paper on his work at the 2009 National Conference on Undergraduate Research (NCUR22). In this report, I discuss recent progress on the measurements of the neutron magnetic form factor and describe my service work for the CLAS Collaboration.

Vineyard, Michael F.

2011-03-31T23:59:59.000Z

258

Electromagnetic anti-jam telemetry tool  

DOE Patents (OSTI)

A mud-pulse telemetry tool includes a tool housing, a motor disposed in the tool housing, and a magnetic coupling coupled to the motor and having an inner shaft and an outer shaft. The tool may also include a stator coupled to the tool housing, a restrictor disposed proximate the stator and coupled to the magnetic coupling, so that the restrictor and the stator adapted to generate selected pulses in a drilling fluid when the restrictor is selectively rotated. The tool may also include a first anti-jam magnet coupled to the too housing, and an second anti-jam magnet disposed proximate the first anti-jam magnet and coupled to the inner shaft and/or the outer shaft, wherein at least one of the first anti-jam magnet and the second anti-jam magnet is an electromagnet, and wherein the first anti-jam magnet and the second anti-jam magnet are positioned with adjacent like poles.

Ganesan, Harini (Sugar Land, TX); Mayzenberg, Nataliya (Missouri City, TX)

2008-02-12T23:59:59.000Z

259

Visualisation of Tensor Time Domain Electromagnetic Data  

DOE Green Energy (OSTI)

Long Offset Time Domain Electromagnetic (LOTEM) measurements traditionally use a single current source. By using a second source, a tensor analysis technique analogous to that used in DC resistivity multiple-source bipole-dipole surveying, is possible. An instantaneous apparent resistivity tensor is defined as the relationship between the time varying (total) electric field and the DC half space current density vectors due to each source. If the sources are dipoles the three coordinate invariant apparent resistivities of the tensor are independent of source orientation. For a uniform half space, one of the invariants is virtually constant in time, deviating from the half space resistivity by a maximum of 6%. This method provides a way in which the complicated data set obtained during a tensor LOTEM survey can be presented in a compact and intelligible form, and has many advantages over conventional methods of analyzing LOTEM data particularly where the resistivity distribution is three dimensional (3D). Results from a 3D resistivity model of an idealized geothermal reservoir and outflow structure are used to illustrate the power of this analysis.

Caldwell, T.G.; Bibby, H.M.

1995-01-01T23:59:59.000Z

260

Electromagnetic polarizabilities: Lattice QCD in background fields  

Science Conference Proceedings (OSTI)

Chiral perturbation theory makes definitive predictions for the extrinsic behavior of hadrons in external electric and magnetic fields. Near the chiral limit, the electric and magnetic polarizabilities of pions, kaons, and nucleons are determined in terms of a few well-known parameters. In this limit, hadrons become quantum mechanically diffuse as polarizabilities scale with the inverse square-root of the quark mass. In some cases, however, such predictions from chiral perturbation theory have not compared well with experimental data. Ultimately we must turn to first principles numerical simulations of QCD to determine properties of hadrons, and confront the predictions of chiral perturbation theory. To address the electromagnetic polarizabilities, we utilize the background field technique. Restricting our attention to calculations in background electric fields, we demonstrate new techniques to determine electric polarizabilities and baryon magnetic moments for both charged and neutral states. As we can study the quark mass dependence of observables with lattice QCD, the lattice will provide a crucial test of our understanding of low-energy QCD, which will be timely in light of ongoing experiments, such as at COMPASS and HI gamma S.

W. Detmold, B.C. Tiburzi, A. Walker-Loud

2012-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

The ALICE electromagnetic calorimeter high level triggers  

E-Print Network (OSTI)

The ALICE (A Large Ion Collider Experiment) detector yields a huge sample of data from different sub-detectors. On-line data processing is applied to select and reduce the volume of the stored data. ALICE applies a multi-level hardware trigger scheme where fast detectors are used to feed a three-level (L0, L1, and L2) deep chain. The High-Level Trigger (HLT) is a fourth filtering stage sitting logically between the L2 trigger and the data acquisition event building. The EMCal detector comprises a large area electromagnetic calorimeter that extends the momentum measurement of photons and neutral mesons up to $p_T=250$ GeV/c, which improves the ALICE capability to perform jet reconstruction with measurement of the neutral energy component of jets. An online reconstruction and trigger chain has been developed within the HLT framework to sharpen the EMCal hardware triggers, by combining the central barrel tracking information with the shower reconstruction (clusters) in the calorimeter. In the present report the status and the functionality of the software components developed for the EMCal HLT online reconstruction and trigger chain will be discussed, as well as preliminary results from their commissioning performed during the 2011 LHC running period.

F. Ronchetti; F. Blanco; M. Figueredo; A. G. Knospe; L. Xaplanteris for the ALICE HLT Collaboration

2012-09-17T23:59:59.000Z

262

Calibrating Accelerometers Using an Electromagnetic Launcher  

SciTech Connect

A Pulse Forming Network (PFN), Helical Electromagnetic Launcher (HEML), Command Module (CM), and Calibration Table (CT) were built and evaluated for the combined ability to calibrate an accelerometer. The PFN has a maximum stored energy of 19.25 kJ bank and is fired by a silicon controlled rectifier (SCR), with appropriate safety precautions. The HEML is constructed out of G-10 fiberglass and is designed to accelerate 600 grams to 10 meters per second. The CM is microcontroller based running Arduino Software. The CM has a keypad input and 7 segment outputs of the bank voltage and desired voltage. After entering a desired bank voltage, the CM controls the charge of the PFN. When the two voltages are equal it allows the fire button to send a pulse to the SCR to fire the PFN and in turn, the HEML. The HEML projectile's tip hits a target that is held by the CT. The CT consists of a table to hold the PFN and HEML, a vacuum chuck, air bearing, velocity meter and catch pot. The Target is held with the vacuum chuck awaiting impact. After impact, the air bearing allows the target to fall freely for the velocity meter to get an accurate reading. A known acceleration is determined from the known change in velocity of the target. Thus, if an accelerometer was attached to the target, the measured value can be compared to the known value.

Erik Timpson

2012-05-13T23:59:59.000Z

263

Horizontal electromagnetic casting of thin metal sheets  

DOE Patents (OSTI)

Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

1987-01-01T23:59:59.000Z

264

Horizontal electromagnetic casting of thin metal sheets  

DOE Patents (OSTI)

Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

1988-01-01T23:59:59.000Z

265

Aeromagnetic Survey At Mt St Helens Area (Towle, 1983) | Open Energy  

Open Energy Info (EERE)

Towle, 1983) Towle, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Aeromagnetic Survey At Mt St Helens Area (Towle, 1983) Exploration Activity Details Location Mt St Helens Area Exploration Technique Aeromagnetic Survey Activity Date Usefulness useful DOE-funding Unknown Notes The VLF method has proved useful in mapping the crater and central dome of Mount St. Helens. More detailed and extensive VLF investigations as well as other electrical and electromagnetic studies will be useful in determining the electrical structure of Mount St. Helens in more detail. Electrical and electromagnetic methods would be especially useful in determining the actual electrical conductivity of partial melt beneath the dome. The ability of these methods to determine the correlation of surface features

266

Interaction of extremely-low-frequency electromagnetic fields with living systems  

SciTech Connect

The sources and physical properties of extremely-low-frequency (ELF) electromagnetic fields are described in this paper. Biological effects and mechanisms through which ELF fields interact with humans and other organisms are discussed, including several aspects of this subject that are presently under active laboratory investigation. Studies on the potential health effects of ELF fields present in the home and workplace are also summarized, including a critical evaluation of evidence for a possible linkage between exposure to ELF fields and cancer risk. 53 refs.

Tenforde, T.S.

1991-11-01T23:59:59.000Z

267

Polarization and spatial coherence of electromagnetic waves in uncorrelated disordered media  

E-Print Network (OSTI)

Spatial field correlation functions represent a key quantity for the description of mesoscopic phenomena in disordered media and the optical characterization of complex materials. Yet many aspects related to the vector nature of light waves have not been investigated so far. We study theoretically the polarization and coherence properties of electromagnetic waves produced by a dipole source in a three-dimensional uncorrelated disordered medium. The spatial field correlation matrix is calculated analytically using a multiple scattering theory for polarized light. This allows us to provide a formal description of the light depolarization process in terms of "polarization eigenchannels" and to derive analytical formulas for the spatial coherence of multiply-scattered light.

Vynck, Kevin; Carminati, Rmi

2013-01-01T23:59:59.000Z

268

On electromagnetic induction in electric conductors  

E-Print Network (OSTI)

Experimental validation of the Faraday's law of electromagnetic induction (EMI) is performed when an electromotive force is generated in thin copper turns, located inside a large magnetic coil. It has been established that the electromotive force (emf) value should be dependent not only on changes of the magnetic induction flux through a turn and on symmetry of its crossing by magnetic power lines also. The law of EMI is applicable in sufficient approximation in case of the changes of the magnetic field near the turn are symmetrical. Experimental study of the induced emf in arcs and a direct section of the conductor placed into the variable field has been carried out. Linear dependence of the induced emf on the length of the arc has been ascertained in case of the magnetic field distribution symmetry about it. Influence of the magnetic field symmetry on the induced emf in the arc has been observed. The curve of the induced emf in the direct section over period of current pulse is similar to this one for the turns and arcs. The general law of EMI for a curvilinear conductor has been deduced. Calculation of the induced emf in the turns wrapped over it and comparison with the experimental data has been made. The proportionality factor has been ascertained for the law. Special conditions have been described, when the induced emf may not exist in the presence of inductive current. Theoretical estimation of the inductive current has been made at a induced low voltage in the turn. It has been noted the necessity to take into account the concentration of current carriers in calculation of the induced emf in semiconductors and ionized conductors.

Alexander I. Korolev

2013-02-22T23:59:59.000Z

269

The crosswell electromagnetic response of layered media  

SciTech Connect

Crosswell electromagnetic measurements are a promising new geophysical technique for mapping subsurface electrical conductivity which can provide information about the subsurface distribution of water, oil or steam. In this work the fields from a low frequency vertical magnetic dipole have been examined from the specific point of view of their application to the determination of the conductivity of a layered medium. The source and the receiver were placed inside two separate boreholes. The range of penetration of such a crosswell system for typical earth resistivities and for currently available transmitter and receiver technologies was found to be up to 1,000 meters so problems in ground water and petroleum reservoir characteristics can be practically examined. An analysis of the behavior of the magnetic fields at the boundary between two half-spaces showed that the horizontal magnetic field component, H{rho}, and the vertical derivative of a vertical component, {delta}H{sub z}/{delta}z, are more sensitive to conductivity variations than H{sub z}. The analysis of derivatives led to the concept of measuring the conductivity directly using a second vertical derivative of H{sub z}. Conductivity profiles interpreted from field data using this technique reproduced accurately the electrical logs for a test site near Devine, Texas. It was found in this study that the inversion techniques are more stable when the first vertical derivative of H{sub z} is used rather than H{sub z} itself. Using data from a salt water injection experiment at the Richmond Field test site in Berkeley it was also found that these robust layer inversions were successful in identifying the preferential flow direction of the injected brine to four boreholes surrounding the injection well.

Deszcz-Pan, M. [Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering]|[Lawrence Berkeley Lab., CA (United States). Earth Sciences Div.

1994-04-01T23:59:59.000Z

270

Control and monitoring method and system for electromagnetic forming processes  

DOE Patents (OSTI)

A process, system, and improvement for a process for electromagnetic forming of a workpiece in which characteristics of the workpiece such as its geometry, electrical conductivity, quality, and magnetic permeability can be determined by monitoring the current and voltage in the workcoil. In an electromagnet forming process in which a power supply provides current to a workcoil and the electromagnetic field produced by the workcoil acts to form the workpiece, the dynamic interaction of the electromagnetic fields produced by the workcoil with the geometry, electrical conductivity, and magnetic permeability of the workpiece, provides information pertinent to the physical condition of the workpiece that is available for determination of quality and process control. This information can be obtained by deriving in real time the first several time derivatives of the current and voltage in the workcoil. In addition, the process can be extended by injecting test signals into the workcoil during the electromagnetic forming and monitoring the response to the test signals in the workcoil. 3 figs.

Kunerth, D.C.; Lassahn, G.D.

1989-06-30T23:59:59.000Z

271

Electromagnetic-Guided Dynamic Multileaf Collimator Tracking Enables Motion Management for Intensity-Modulated Arc Therapy  

SciTech Connect

Purpose: Intensity-modulated arc therapy (IMAT) is attractive because of high-dose conformality and efficient delivery. However, managing intrafraction motion is challenging for IMAT. The purpose of this research was to develop and investigate electromagnetically guided dynamic multileaf collimator (DMLC) tracking as an enabling technology to treat moving targets during IMAT. Methods and Materials: A real-time three-dimensional DMLC-based target tracking system was developed and integrated with a linear accelerator. The DMLC tracking software inputs a real-time electromagnetically measured target position and the IMAT plan, and dynamically creates new leaf positions directed at the moving target. Low- and high-modulation IMAT plans were created for lung and prostate cancer cases. The IMAT plans were delivered to a three-axis motion platform programmed with measured patient motion. Dosimetric measurements were acquired by placing an ion chamber array on the moving platform. Measurements were acquired with tracking, without tracking (current clinical practice), and with the phantom in a static position (reference). Analysis of dose distribution differences from the static reference used a {gamma}-test. Results: On average, 1.6% of dose points for the lung plans and 1.2% of points for the prostate plans failed the 3-mm/3% {gamma}-test with tracking; without tracking, 34% and 14% (respectively) of points failed the {gamma}-test. The delivery time was the same with and without tracking. Conclusions: Electromagnetic-guided DMLC target tracking with IMAT has been investigated for the first time. Dose distributions to moving targets with DMLC tracking were significantly superior to those without tracking. There was no loss of treatment efficiency with DMLC tracking.

Keall, Paul J., E-mail: paul.keall@stanford.ed [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Sawant, Amit; Cho, Byungchul; Ruan, Dan; Wu Junqing; Poulsen, Per [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Petersen, Jay; Newell, Laurence J. [Calypso Medical Technologies, Seattle, WA (United States); Cattell, Herbert [Varian Medical Systems, Palo Alto, CA (United States); Korreman, Stine [Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Department of Human Oncology, University of Wisconsin-Madison, Madison, WI (United States)

2011-01-01T23:59:59.000Z

272

Method for imaging with low frequency electromagnetic fields  

DOE Patents (OSTI)

A method for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The traveltimes corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter .alpha. for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography.

Lee, Ki H. (Lafayette, CA); Xie, Gan Q. (Berkeley, CA)

1994-01-01T23:59:59.000Z

273

Through-Barrier Electromagnetic Communication and Sensing: Advances in  

NLE Websites -- All DOE Office Websites (Extended Search)

Through-Barrier Electromagnetic Communication and Sensing: Advances in Through-Barrier Electromagnetic Communication and Sensing: Advances in Wideband Radio-Wave Communications and ..... Speaker(s): Farid Dowla Date: June 1, 2007 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Mary Ann Piette (Complete seminar title is: Through-Barrier Electromagnetic Communication and Sensing: Advances in Wideband Radio-Wave Communications and Radar Imaging, Radio-Frequency (RF) Tags and Tera-Hertz (THz) Standoff Detection Spectroscopy) In many remote sensing problems there is a critical need to detect and image objects through barriers, such as buildings, with high reliability and resolution and at long ranges. A related problem is the wireless communication and geolocation of transceivers in harsh RF environments, such as in urban areas and underground caves, where

274

Z-Axis Tipper Electromagnetics | Open Energy Information  

Open Energy Info (EERE)

Z-Axis Tipper Electromagnetics Z-Axis Tipper Electromagnetics Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Z-Axis Tipper Electromagnetics Details Activities (2) Areas (2) Regions (0) NEPA(1) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Magnetotelluric Techniques Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Cost Information Low-End Estimate (USD): 4,827.00482,700 centUSD 4.827 kUSD 0.00483 MUSD 4.827e-6 TUSD / mile Median Estimate (USD): 6,206.14620,614 centUSD 6.206 kUSD 0.00621 MUSD 6.20614e-6 TUSD / mile High-End Estimate (USD): 17,239.291,723,929 centUSD 17.239 kUSD 0.0172 MUSD 1.723929e-5 TUSD / mile Dictionary.png

275

Electromagnetic Transition in Waveguide with Application to Lasers  

E-Print Network (OSTI)

The electromagnetic transition of two-level atomic systems in a waveguide is calculated. Compared with the result in free space, the spontaneous emission rate decrease because the phase space is smaller, and meanwhile, some resonance appears in some cases. Moreover, the influence of non-uniform electromagnetic field in a waveguide on absorption and stimulated emission is considered. Applying the results to lasers, a method to enhance the laser power is proposed. PACS codes: 42.50.ct, 42.55.Ah 1

unknown authors

2002-01-01T23:59:59.000Z

276

Improved Magnetic Fusion Energy Economics via Massive Resistive Electromagnets  

SciTech Connect

Abandoning superconductors for magnetic fusion reactors and instead using resistive magnet designs based on cheap copper or aluminum conductor material operating at "room temperature" (300 K) can reduce the capital cost per unit fusion power and simplify plant operations. By increasing unit size well beyond that of present magnetic fusion energy conceptual designs using superconducting electromagnets, the recirculating power fraction needed to operate resistive electromagnets can be made as close to zero as needed for economy without requiring superconductors. Other advantages of larger fusion plant size, such as very long inductively driven pulses, may also help reduce the cost per unit fusion power.

Woolley, R.D.

1998-08-19T23:59:59.000Z

277

Recoil polarization measurements of the proton electromagnetic form factor ratio to high momentum transfer  

E-Print Network (OSTI)

The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions ...

Puckett, Andrew James Ruehe

2010-01-01T23:59:59.000Z

278

In-Flight Characterization of the Electromagnetic Environment Inside an Airliner  

Science Conference Proceedings (OSTI)

In 1995, the NASA Langley Research Center conducted a series of experimental measurements that characterized the electromagnetic environment (EME) inside a Boeing 757 airliner while in flight. Measurements were made of the electromagnetic energy coupled ...

Moeller Karl J.; Dudley Kenneth L.; Quach Cuong C.; Koppen Sandra V.

2001-03-01T23:59:59.000Z

279

Rayleigh-Taylor-Induced electromagnetic fields in laser-produced plasmas  

E-Print Network (OSTI)

Spontaneous electromagnetic fields can be important to the dynamic evolution of a plasma by directing heat flow as well as providing additional pressures on the conducting fluids through the Lorentz force. Electromagnetic ...

Manuel, Mario John-Errol

2013-01-01T23:59:59.000Z

280

Electromagnetic analysis of forces and torques on the ITER shield modules due to plasma disruption.  

SciTech Connect

An electromagnetic analysis is performed on the ITER shield modules under different plasma disruption scenarios using the OPERA-3d software. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

2009-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Cryogenic heat pipe for cooling high temperature superconductors with application to Electromagnetic Formation Flight Satellites  

E-Print Network (OSTI)

An emerging method of propellant-less formation flight propulsion is the use of electromagnets coupled with reaction wheels. This technique is called Electromagnetic Formation Flight (EMFF). In order to create a large ...

Kwon, Daniel W., 1980-

2009-01-01T23:59:59.000Z

282

Laboratory Studies of the Short-term Responses of Freshwater Fish to Electromagnetic Fields  

Science Conference Proceedings (OSTI)

Hydrokinetic energy technologies are being proposed as an environmentally preferred means of generating electricity from river and tidal currents. Among the potential issues that must be investigated in order to resolve environmental concerns are the effects on aquatic organisms of electromagnetic fields created by underwater generators and transmission cables. The behavioral responses of common freshwater fishes to static and variable electromagnetic fields (EMF) that may be emitted by hydrokinetic projects were evaluated in laboratory experiments. Various fish species were exposed to either static (DC) EMF fields created by a permanent bar magnet or variable (AC) EMF fields created by a switched electromagnet for 48 h, fish locations were recorded with a digital imaging system, and changes in activity level and distribution relative to the magnet position were quantified at 5-min intervals. Experiments with fathead minnows, redear sunfish, striped bass, lake sturgeon, and channel catfish produced mixed results. Except for fathead minnows there was no effect on activity level. Only redear sunfish and channel catfish exhibited a change in distribution relative to the position of the magnet with an apparent attraction to the EMF source. In separate experiments, rapid behavioral responses of paddlefish and lake sturgeon to onset of the AC field were recorded with high-speed video. Paddlefish did not react to a variable, 60-Hz magnetic field like that which would be emitted by an AC generator or cable, but lake sturgeon consistently responded to the variable, AC-generated magnetic field with a variety of altered swimming behaviors. These results will be useful for determining under what circumstances cables or generators need to be positioned to minimize interactions with sensitive species.

Bevelhimer, Mark S [ORNL; Cada, Glenn F [ORNL; Fortner, Allison M [ORNL; Schweizer, Peter E [ORNL; Riemer, Kristina P [ORNL

2013-01-01T23:59:59.000Z

283

Parallel Magnetic Flow Electromagnet for Movable Coil Control-rod Driving Mechanism  

SciTech Connect

The parallel magnetic flow electromagnet can effectively relax the saturation, which easily takes place in the single magnetic flow electromagnet, and accordingly can improve the drive capacity of the movable coil electromagnet drive mechanism for a mobile reactor control rod. (authors)

Jige, Zhang [School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, P.R.China, 1954 Huashan road, Shanghai (China)

2006-07-01T23:59:59.000Z

284

Influence of lateral target size on hot electron production and electromagnetic pulse emission from laser-irradiated metallic targets  

SciTech Connect

The influences of lateral target size on hot electron production and electromagnetic pulse emission from laser interaction with metallic targets have been investigated. Particle-in-cell simulations at high laser intensities show that the yield of hot electrons tends to increase with lateral target size, because the larger surface area reduces the electrostatic field on the target, owing to its expansion along the target surface. At lower laser intensities and longer time scales, experimental data characterizing electromagnetic pulse emission as a function of lateral target size also show target-size effects. Charge separation and a larger target tending to have a lower target potential have both been observed. The increase in radiation strength and downshift in radiation frequency with increasing lateral target size can be interpreted using a simple model of the electrical capacity of the target.

Chen Ziyu; Li Jianfeng; Yu Yong; Li Xiaoya; Peng Qixian; Zhu Wenjun [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China); Wang Jiaxiang [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China)

2012-11-15T23:59:59.000Z

285

Electromagnetic pump stator frame having power crossover struts  

DOE Patents (OSTI)

A stator frame for an electromagnetic pump includes a casing joined to a hub by a plurality of circumferentially spaced apart struts. At least one electrically insulated power crossover lead extends through the hub, through a crossover one of the struts, and through the casing for carrying electrical current therethrough.

Fanning, Alan W. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1995-01-01T23:59:59.000Z

286

Electromagnetically induced vorticity control in a quantum fluid velocity field  

E-Print Network (OSTI)

A new method is reported by which it is possible to induce certain flux configurations of desired characteristics via electromagnetic means into the overall quantum probability current of a many-body system in the Madelung hydrodynamic picture. Some indicative applications are also considered with emphasis in HTC and gravitational wave research.

T. E. Raptis

2013-06-19T23:59:59.000Z

287

Gravitational Waves versus Electromagnetic Emission in Gamma-Ray Bursts  

E-Print Network (OSTI)

The recent progress in the understanding the physical nature of neutron star equilibrium configurations and the first observational evidence of a genuinely Short Gamma-Ray Burst, GRB 090227B, allows to give an estimate of the gravitational waves versus electromagnetic emission in a Gamma-Ray Burst.

Jorge A. Rueda; Remo Ruffini

2012-05-31T23:59:59.000Z

288

Electromagnetic fields and transport coefficients in a hot pion gas  

E-Print Network (OSTI)

We present recent results on finite temperature electromagnetic form factors and the electrical conductivity in a pion gas. The standard Chiral Perturbation Theory power counting needs to be modified for transport coefficients. We pay special attention to unitarity and to possible applications for dilepton and photon production.

A. Gomez Nicola; D. Fernandez-Fraile

2006-08-24T23:59:59.000Z

289

A characterization of the electromagnetic stress-energy tensor  

E-Print Network (OSTI)

In a previous paper, we pointed out how a dimensional analysis of the stress-energy tensor of the gravitational field allows to derive the field equation of General Relativity. In this note, we comment an analogous reasoning in presence of a 2-form, that allows to characterize the so called electromagnetic stress-energy tensor.

J. Navarro; J. B. Sancho

2011-01-13T23:59:59.000Z

290

On Scattering of Electromagnetic Waves by a Wormhole  

E-Print Network (OSTI)

We consider scattering of a plane electromagnetic wave by a wormhole. It is found that the scattered wave is partially depolarized and has a specific interference picture depending on parameters of the wormhole and the distance to the observer. It is proposed that such features can be important in the direct search of wormholes.

A. A. Kirillov; E. P. Savelova

2011-03-06T23:59:59.000Z

291

On Scattering of Electromagnetic Waves by a Wormhole  

E-Print Network (OSTI)

We consider scattering of a plane electromagnetic wave by a wormhole. It is found that the scattered wave is partially depolarized and has a specific interference picture depending on parameters of the wormhole and the distance to the observer. It is proposed that such features can be important in the direct search of wormholes.

Kirillov, A A

2011-01-01T23:59:59.000Z

292

Electromagnetic interferences from plasmas generated in meteoroids impacts  

E-Print Network (OSTI)

Submitted to Europhysics Letters. It is shown that the plasma, generated during an impact of a meteoroid with an artificial satellite, can produce electromagnetic radiations below the microwave frequency range. These interferences can disturb the regular satellite operations. Pacs 96.50.Kr: Meteors and meteoroids. Pacs 52.50.Lp: Plasma production and heating by shock waves and compression.

Luigi Foschini

1998-01-01T23:59:59.000Z

293

Metallic Mesh Filter Used for Electromagnetic Shielding of Infrared Window  

Science Conference Proceedings (OSTI)

In order to meet anti-electromagnetism interference performance requirements of infrared window, a metallic mesh coating must be used on the infrared window. From the diffraction theory of grating and the equivalent circuit method, simplified expressions ... Keywords: stealth technology, electro-optical countermeasure, transparent conductive coating, metallic mesh filter, infrared window

Jia-Li Song, Xiao-Guo Feng

2012-07-01T23:59:59.000Z

294

Electromagnetic energy flow lines as possible paths of photons  

E-Print Network (OSTI)

Motivated by recent experiments where interference patterns behind a grating are obtained by accumulating single photon events, here we provide an electromagnetic energy flow-line description to explain the emergence of such patterns. We find and discuss an analogy between the equation describing these energy flow lines and the equation of Bohmian trajectories used to describe the motion of massive particles.

M. Davidovic; A. S. Sanz; D. Arsenovic; M. Bozic; S. Miret-Artes

2008-05-21T23:59:59.000Z

295

Electromagnetic interferences from plasmas generated in meteoroids impacts  

E-Print Network (OSTI)

It is shown that the plasma, generated during an impact of a meteoroid with an artificial satellite, can produce electromagnetic radiation below the microwave frequency range. This interference is shown to exceed local noise sources and might disturb regular satellite operations.

Luigi Foschini

1998-04-23T23:59:59.000Z

296

Remote Sensing Ayman F. Habib Electro-Magnetic Radiation  

E-Print Network (OSTI)

Remote Sensing Ayman F. Habib 1 Chapter 2 Electro-Magnetic Radiation #12;Remote Sensing Ayman F. Habib 2 Elements of Remote Sensing #12;Remote Sensing Ayman F. Habib 3 Chapter 2 Radiation: nature & source #12;Remote Sensing Ayman F. Habib 4 Chapter 2 Interaction with the atmosphere #12;Remote Sensing

Habib, Ayman

297

Remote Sensing Ayman F. Habib Electro-Magnetic Radiation  

E-Print Network (OSTI)

Remote Sensing Ayman F. Habib 1 Chapter 2 Electro-Magnetic Radiation Remote Sensing Ayman F. Habib 2 Elements of Remote Sensing #12;Remote Sensing Ayman F. Habib 3 Chapter 2 Radiation: nature & source Remote Sensing Ayman F. Habib 4 Chapter 2 Interaction with the atmosphere #12;Remote Sensing Ayman

Habib, Ayman

298

Monitoring Electromagnetic Pollution: A GIS-Based Visual Approach  

Science Conference Proceedings (OSTI)

In the last years, the attention of the public community on electro-magnetic pollution has continuously grown. In this paper we argue that the use of Geographic Information Systems in this domain should be encouraged as a valid support to the monitoring ...

Luca Paolino; Monica Sebillo; Genoveffa Tortora; Giuliana Vitiello

2001-09-01T23:59:59.000Z

299

Three-dimensional transient electromagnetic modeling in the Laplace Domain  

Science Conference Proceedings (OSTI)

In modeling electromagnetic responses, Maxwell's equations in the frequency domain are popular and have been widely used (Nabighian, 1994; Newman and Alumbaugh, 1995; Smith, 1996, to list a few). Recently, electromagnetic modeling in the time domain using the finite difference (FDTD) method (Wang and Hohmann, 1993) has also been used to study transient electromagnetic interactions in the conductive medium. This paper presents a new technique to compute the electromagnetic response of three-dimensional (3-D) structures. The proposed new method is based on transforming Maxwell's equations to the Laplace domain. For each discrete Laplace variable, Maxwell's equations are discretized in 3-D using the staggered grid and the finite difference method (FDM). The resulting system of equations is then solved for the fields using the incomplete Cholesky conjugate gradient (ICCG) method. The new method is particularly effective in saving computer memory since all the operations are carried out in real numbers. For the same reason, the computing speed is faster than frequency domain modeling. The proposed approach can be an extremely useful tool in developing an inversion algorithm using the time domain data.

Mizunaga, H.; Lee, Ki Ha; Kim, H.J.

1998-09-01T23:59:59.000Z

300

Measurement and characterization of substation electromagnetic transients. Final report  

SciTech Connect

Little quantitative data exists on radiated electromagnetic interference in substations arising from substation transients. The electromagnetic transient noise produced by normal substation activity such as opening switches and breakers can be significant. Additionally, abnormal events such as faults cause similar electromagnetic noise. The lack of data is in part because suitable measurement equipment techniques have not been generally available to utilities. A new approach to the measurement and characterization of electromagnetic interference caused by substation transients has been developed. A data acquisition system for measurements has been designed and constructed for field use with a bandwidth capability exceeding 100 MHz. Measurements have been taken from staged operations in substations and the resulting data analyzed using specialized computer programs developed for this project. The measurement techniques are presented and the analysis procedures explained in detail. The transients caused by equipment operations in several substations have been studied resulting in an understanding of the expected or typical amplitudes and frequencies of the resulting noise. Suggestions as to equipment tests and withstand levels have been made. An appendix includes raw and analyzed data for research use.

Russell, B.D.

1983-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

The electromagnetic calorimeter for the STAR experiment at RHIC  

SciTech Connect

The STAR detector at RHIC can be used both for searches for quark-gluon plasma and for high energy pp spin physics. An electromagnetic calorimeter is being planned which will be used for triggering on High pt direct gammas, e[sup [plus minus

Underwood, D.G.

1992-01-01T23:59:59.000Z

302

Electromagnetically induced transparency over spectral hole-burning  

E-Print Network (OSTI)

Electromagnetically induced transparency over spectral hole-burning temperature in a rare the spectral hole-burning temperature. The transmission of the probe laser beam is increased by a factor of exp over the spectral hole-burning temperature in a rare-earth­doped solid represents important progress

Shahriar, Selim

303

Mapping clay content variation using electromagnetic induction techniques  

Science Conference Proceedings (OSTI)

Effective management of the soil resource requires basic information about the spatial distribution of various attributes. A method widely used for providing spatial information is a combination of sampling strategies and geostatistics. However, geostatistical ... Keywords: EM34, EM38, Electromagnetic induction, Fuzzy k-means and extragrades classification, Spatial response surface sampling

J. Triantafilis; S. M. Lesch

2005-03-01T23:59:59.000Z

304

Is the Gas-Fed PPT an Electromagnetic Accelerator? An Investigation using Measured Performance  

E-Print Network (OSTI)

operating at low mass bits (pump oil to reduce diffusion pump oil backstreaming were implemented and are discussed. A portion of the database has been dupli- cated in a cryo-pumped facility at NASA-JPL to ver- ify that the contamination effects have

Choueiri, Edgar

305

Electromagnetic Pulse and Intentional Electromagnetic Interference (EMI) Threats to the Power Grid: Characterization of the Threat, Available Countermeasures, and Opportunities for Technology Research  

Science Conference Proceedings (OSTI)

In 2012, the Electric Power Research Institute (EPRI) researched and published a white paper that provided background and an introduction to the topic of electromagnetic attacks of various forms, including electromagnetic pulse (EMP), high altitude EMP (HEMP), and intentional electromagnetic interference (IEMI). That white paper was the first in a series of EPRI papers and reports that address the potential impacts ofand mitigation strategies forvarious types of high-impact, ...

2013-12-22T23:59:59.000Z

306

A Numerical Evaluation Of Electromagnetic Methods In Geothermal Exploration  

Open Energy Info (EERE)

GEOTHERMAL ENERGYGeothermal Home GEOTHERMAL ENERGYGeothermal Home Journal Article: A Numerical Evaluation Of Electromagnetic Methods In Geothermal Exploration Details Activities (0) Areas (0) Regions (0) Abstract: The size and low resistivity of the clay cap associated with a geothermal system create a target well suited for electromagnetic (EM) methods and also make electrical detection of the underlying geothermal reservoir a challenge. Using 3-D numerical models, we evaluate four EM techniques for use in geothermal exploration: magnetotellurics (MT), controlled-source audio magnetotellurics (CSAMT), long-offset time-domain EM (LOTEM), and short-offset time-domain EM (TEM). Our results show that all of these techniques can delineate the clay cap, but none can be said to unequivocally detect the reservoir. We do find, however, that the EM

307

Evidence for new nucleon resonances from electromagnetic meson production  

Science Conference Proceedings (OSTI)

The study of nucleon resonances in electromagnetic meson production with the CLAS detector is discussed. The electromagnetic interaction is complementary to pion scattering in the exploration of the nucleon excitation spectrum. Higher mass states often decouple from the N{pi} channel and are not seen in {pi} N --> {pi} N. Photoproduction of mesons, such as K {Lambda}, {omega} p and {eta}' p may be more sensitive to many of these states. The CLAS detector, combined with the use of energy-tagged polarized photons and polarized electrons, as well as po- larized targets and the measurement of recoil polarization, are the tools needed for a comprehensive nucleon resonance program. Some of the recently published high statistics data sets had significant impact on further clarifying the nucleon excitation spectrum.

Volker Burkert

2012-12-01T23:59:59.000Z

308

On kinetic description of electromagnetic processes in a quantum plasma  

E-Print Network (OSTI)

A nonlinear kinetic equation for nonrelativistic quantum plasma with electromagnetic interaction of particles is obtained in the Hartree's mean-field approximation. It is cast in a convenient form of Vlasov-Boltzmann-type equation with "quantum interference integral", that allows for relatively straightforward modification of existing classical Vlasov codes to incorporate quantum effects (quantum statistics and quantum interference of overlapping particles wave functions), without changing the bulk of the codes. Such modification (upgrade) of existing Vlasov codes may provide a direct and effective path to numerical simulations of nonlinear electrostatic and electromagnetic phenomena in quantum plasmas, especially of processes where kinetic effects are important (e.g., modulational interactions and stimulated scattering phenomena involving plasma modes at short wavelengths or high-order kinetic modes, dynamical screening and interaction of charges in quantum plasma, etc.) Moreover, numerical approaches involv...

Tyshetskiy, Y O; Kompaneets, R

2011-01-01T23:59:59.000Z

309

Geometric and Electromagnetic Aspects of Fusion Pore Making  

E-Print Network (OSTI)

For regulated exocytosis, we model the morphology and dynamics of the making of the fusion pore or porosome as a cup-shaped lipoprotein structure (a dimple or pit) on the cytosol side of the plasma membrane. We describe the forming of the dimple by a free boundary problem. We discuss the various forces acting and analyze the magnetic character of the wandering electromagnetic field wave produced by intracellular spatially distributed pulsating (and well observed) release and binding of calcium ions anteceding the bilayer membrane vesicle fusion of exocytosis. Our approach explains the energy efficiency of the observed dimple forming prior to hemifusion and fusion pore, and the observed flickering in secretion. It provides a frame to relate characteristic time length of exocytosis to the frequency, amplitude and direction of propagation of the underlying electromagnetic field wave.

Darya Apushkinskaya; Evgeny Apushkinsky; Bernhelm Booss-Bavnbek; Martin Koch

2009-12-18T23:59:59.000Z

310

Structures, systems and methods for harvesting energy from electromagnetic radiation  

DOE Patents (OSTI)

Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.

Novack, Steven D. (Idaho Falls, ID); Kotter, Dale K. (Shelley, ID); Pinhero, Patrick J. (Columbia, MO)

2011-12-06T23:59:59.000Z

311

Energy harvesting devices for harvesting energy from terahertz electromagnetic radiation  

DOE Patents (OSTI)

Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.

Novack, Steven D.; Kotter, Dale K.; Pinhero, Patrick J.

2012-10-09T23:59:59.000Z

312

Structures, systems and methods for harvesting energy from electromagnetic radiation  

Science Conference Proceedings (OSTI)

Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.

Novack, Steven D. (Idaho Falls, ID); Kotter, Dale K. (Shelley, ID); Pinhero, Patrick J. (Columbia, MO)

2011-12-06T23:59:59.000Z

313

Electromagnetic and nuclear radiation detector using micromechanical sensors  

DOE Patents (OSTI)

Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

Thundat, Thomas G. (Knoxville, TN); Warmack, Robert J. (Knoxville, TN); Wachter, Eric A. (Oak Ridge, TN)

2000-01-01T23:59:59.000Z

314

Electromagnetic Casimir Energies of Semi-Infinite Planes  

E-Print Network (OSTI)

Using recently developed techniques based on scattering theory, we find the electromagnetic Casimir energy for geometries involving semi-infinite planes, a case that is of particular interest in the design of microelectromechanical devices. We obtain both approximate analytic formulae and exact results requiring only modest numerical computation. Using these results, we analyze the effects of edges and orientation on the Casimir energy. We also demonstrate the accuracy, simplicity, and utility of our approximation scheme, which is based on a multiple reflection expansion.

Mohammad F. Maghrebi; Noah Graham

2011-02-08T23:59:59.000Z

315

Enhanced Interpretation of Electromagnetic Signature Analysis for Large Machines  

Science Conference Proceedings (OSTI)

This project developed and applied frequency domain models to enhance interpretation of electromagnetic signature analysis (EMSA) for large electrical generators. The project's rationale was to provide a prediction of the native frequency response of the winding calculated from machine dimensions and design data so that the positions of the resonances would be known a priore. This procedure allowed augmentation of an EMSA spectrum at the characteristic resonant frequencies of the machine in the interpret...

2010-11-16T23:59:59.000Z

316

Experimental studies of electromagnetic properties of few body systems  

DOE Green Energy (OSTI)

An overview is given of some recent and planned experiments which have or will substantially increase our knowledge of the electromagnetic properties of few body systems. Specific examples include the proton and neutron elastic form factors, the deuteron elastic form factors, deuteron threshold electrodisintegration and quasi-elastic scattering, deuteron photodisintegration, and finally measurements of cross sections in deep inelastic scattering from hydrogen, deuterium, and iron. 47 refs., 13 figs. (DWL)

Bosted, P.E.

1987-08-01T23:59:59.000Z

317

Gradient instabilities of electromagnetic waves in Hall thruster plasma  

SciTech Connect

This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

2013-04-15T23:59:59.000Z

318

Medical Devices: Electromagnetic Interference Status and the Role of Standards  

Science Conference Proceedings (OSTI)

This technical update discusses the role of voluntary and regulatory standards in determining the risks of interference from electric and magnetic fields (EMF) with the functioning of implantable and wearable medical devices. The update covers frequencies from the extremely low frequency (ELF) range through the radio-frequency (RF) range. It augments a 2008 EPRI technical update on electromagnetic interference (EMI) with newer types of implanted medical devices (1016815) and previous EPRI publications th...

2009-12-22T23:59:59.000Z

319

Electromagnetic Interference with Implanted Medical Devices: An Update  

Science Conference Proceedings (OSTI)

Electric and magnetic fields (EMF) and contact currents at both power and radio frequencies can interfere with the functioning of implanted medical electronic devices. In both public and occupational environments, electromagnetic interference issues are now exacerbated by the exponential increase in sources of interference over the last decade, an increasing variety of types of susceptible devices, and greater potential for unintended consequences that can be serious. This technical update discusses pote...

2008-09-18T23:59:59.000Z

320

Technical Design Report for PANDA Electromagnetic Calorimeter (EMC)  

E-Print Network (OSTI)

This document presents the technical layout and the envisaged performance of the Electromagnetic Calorimeter (EMC) for the PANDA target spectrometer. The EMC has been designed to meet the physics goals of the PANDA experiment, which is being developed for the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, Germany. The performance figures are based on extensive prototype tests and radiation hardness studies. The document shows that the EMC is ready for construction up to the front-end electronics interface.

2008-01-01T23:59:59.000Z

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321

Technical Design Report for PANDA Electromagnetic Calorimeter (EMC)  

E-Print Network (OSTI)

This document presents the technical layout and the envisaged performance of the Electromagnetic Calorimeter (EMC) for the PANDA target spectrometer. The EMC has been designed to meet the physics goals of the PANDA experiment, which is being developed for the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, Germany. The performance figures are based on extensive prototype tests and radiation hardness studies. The document shows that the EMC is ready for construction up to the front-end electronics interface.

PANDA Collaboration; W. Erni; I. Keshelashvili; B. Krusche; M. Steinacher; Y. Heng; Z. Liu; H. Liu; X. Shen; O. Wang; H. Xu; J. Becker; F. Feldbauer; F. -H. Heinsius; T. Held; H. Koch; B. Kopf; M. Pelizaeus; T. Schroeder; M. Steinke; U. Wiedner; J. Zhong; A. Bianconi; M. Bragadireanu; D. Pantea; A. Tudorache; V. Tudorache; M. De Napoli; F. Giacoppo; G. Raciti; E. Rapisarda; C. Sfienti; E. Bialkowski; A. Budzanowski; B. Czech; M. Kistryn; S. Kliczewski; A. Kozela; P. Kulessa; K. Pysz; W. Schaefer; R. Siudak; A. Szczurek; W. Czy. zycki; M. Domagala; M. Hawryluk; E. Lisowski; F. Lisowski; L. Wojnar; D. Gil; P. Hawranek; B. Kamys; St. Kistryn; K. Korcyl; W. Krzemien; A. Magiera; P. Moskal; Z. Rudy; P. Salabura; J. Smyrski; A. Wronska; M. Al-Turany; I. Augustin; H. Deppe; H. Flemming; J. Gerl; K. Goetzen; R. Hohler; D. Lehmann; B. Lewandowski; J. Luehning; F. Maas; D. Mishra; H. Orth; K. Peters; T. Saito; G. Schepers; C. J. Schmidt; L. Schmitt; C. Schwarz; B. Voss; P. Wieczorek; A. Wilms; K. -T. Brinkmann; H. Freiesleben; R. Jaekel; R. Kliemt; T. Wuerschig; H. -G. Zaunick; V. M. Abazov; G. Alexeev; A. Arefiev; V. I. Astakhov; M. Yu. Barabanov; B. V. Batyunya; Yu. I. Davydov; V. Kh. Dodokhov; A. A. Efremov; A. G. Fedunov; A. A. Feshchenko; A. S. Galoyan; S. Grigoryan; A. Karmokov; E. K. Koshurnikov; V. Ch. Kudaev; V. I. Lobanov; Yu. Yu. Lobanov; A. F. Makarov; L. V. Malinina; V. L. Malyshev; G. A. Mustafaev; A. Olshevski; M. A. . Pasyuk; E. A. Perevalova; A. A. Piskun; T. A. Pocheptsov; G. Pontecorvo; V. K. Rodionov; Yu. N. Rogov; R. A. Salmin; A. G. Samartsev; M. G. Sapozhnikov; A. Shabratova; G. S. Shabratova; A. N. Skachkova; N. B. Skachkov; E. A. Strokovsky; M. K. Suleimanov; R. Sh. Teshev; V. V. Tokmenin; V. V. Uzhinsky; A. S. Vodopianov; S. A. Zaporozhets; N. I. Zhuravlev; A. G. Zorin; D. Branford; K. Foehl; D. Glazier; D. Watts; P. Woods; W. Eyrich; A. Lehmann; A. Teufel; S. Dobbs; Z. Metreveli; K. Seth; B. Tann; A. Tomaradze; D. Bettoni; V. Carassiti; A. Cecchi; P. Dalpiaz; E. Fioravanti; I. Garzia; M. Negrini; M. Savri`e; G. Stancari; B. Dulach; P. Gianotti; C. Guaraldo; V. Lucherini; E. Pace; A. Bersani; M. Macri; M. Marinelli; R. F. Parodi; I. Brodski; W. Doering; P. Drexler; M. Dueren; Z. Gagyi-Palffy; A. Hayrapetyan; M. Kotulla; W. Kuehn; S. Lange; M. Liu; V. Metag; M. Nanova; R. Novotny; C. Salz; J. Schneider; P. Schoenmeier; R. Schubert; S. Spataro; H. Stenzel; C. Strackbein; M. Thiel; U. Thoering; S. Yang; T. Clarkson; E. Cowie; E. Downie; G. Hill; M. Hoek; D. Ireland; R. Kaiser; T. Keri; I. Lehmann; K. Livingston; S. Lumsden; D. MacGregor; B. McKinnon; M. Murray; D. Protopopescu; G. Rosner; B. Seitz; G. Yang; M. Babai; A. K. Biegun; A. Bubak; E. Guliyev; V. S. Jothi; M. Kavatsyuk; H. Loehner; J. Messchendorp; H. Smit; J. C. van der Weele; F. Garcia; D. -O. Riska; M. Buescher; R. Dosdall; R. Dzhygadlo; A. Gillitzer; D. Grunwald; V. Jha; G. Kemmerling; H. Kleines; A. Lehrach; R. Maier; M. Mertens; H. Ohm; D. Prasuhn; T. Randriamalala; J. Ritman; M. Roeder; T. Stockmanns; P. Wintz; P. Wuestner; J. Kisiel; S. Li; Z. Li; Z. Sun; H. Xu; S. Fissum; K. Hansen; L. Isaksson; M. Lundin; B. Schroeder; P. Achenbach; M. C. Mora Espi; J. Pochodzalla; S. Sanchez; A. Sanchez-Lorente; V. I. Dormenev; A. A. Fedorov; M. V. Korzhik; O. V. Missevitch; V. Balanutsa; V. Chernetsky; A. Demekhin; A. Dolgolenko; P. Fedorets; A. Gerasimov; V. Goryachev; A. Boukharov; O. Malyshev; I. Marishev; A. Semenov; C. Hoeppner; B. Ketzer; I. Konorov; A. Mann; S. Neubert; S. Paul; Q. Weitzel; A. Khoukaz; T. Rausmann; A. Taeschner; J. Wessels; R. Varma; E. Baldin; K. Kotov; S. Peleganchuk; Yu. Tikhonov; J. Boucher; T. Hennino; R. Kunne; S. Ong; J. Pouthas; B. Ramstein; P. Rosier; M. Sudol; J. Van de Wiele; T. Zerguerras; K. Dmowski; R. Korzeniewski; D. Przemyslaw; B. Slowinski; G. Boca; A. Braghieri; S. Costanza; A. Fontana; P. Genova; L. Lavezzi; P. Montagna; A. Rotondi; N. I. Belikov; A. M. Davidenko; A. A. Derevschikov; Y. M. Goncharenko; V. N. Grishin; V. A. Kachanov; D. A. Konstantinov; V. A. Kormilitsin; V. I. Kravtsov; Y. A. Matulenko; Y. M. Melnik; A. P. Meschanin; N. G. Minaev; V. V. Mochalov; D. A. Morozov; L. V. Nogach; S. B. Nurushev; A. V. Ryazantsev; P. A. Semenov; L. F. Soloviev; A. V. Uzunian; A. N. Vasiliev; A. E. Yakutin; T. Baeck; B. Cederwall; C. Bargholtz; L. Geren; P. E. Tegner; S. Belostotski; G. Gavrilov; A. Itzotov; A. Kisselev; P. Kravchenko; S. Manaenkov; O. Miklukho; Y. Naryshkin; D. Veretennikov; V. Vikhrov; A. Zhadanov; L. Fava; D. Panzieri; D. Alberto; A. Amoroso; E. Botta; T. Bressani; S. Bufalino; M. P. Bussa; L. Busso; F. De Mori; M. Destefanis; L. Ferrero; A. Grasso; M. Greco; T. Kugathasan; M. Maggiora; S. Marcello; G. Serbanut; S. Sosio; R. Bertini; D. Calvo; S. Coli; P. De Remigis; A. Feliciello; A. Filippi; G. Giraudo; G. Mazza; A. Rivetti

2008-10-07T23:59:59.000Z

322

Assessment of Electromagnetic Interference Events in Nuclear Power Plants  

Science Conference Proceedings (OSTI)

This report presents a study and analysis of reported electromagnetic interference (EMI-) related incidents in nuclear power plants. These incidents were gathered primarily from the total body of incidents reported to the Institute of Nuclear Power Operations (INPO) database, with a few incidents coming from U.S. Nuclear Regulatory Commission (NRC) reports. This report analyzes trends and common factors in these events. The analysis is intended to inform the estimation of risk from EMI and offer suggesti...

2011-12-23T23:59:59.000Z

323

Device for conversion of electromagnetic radiation into electrical current  

DOE Patents (OSTI)

Electromagnetic energy may be converted directly into electrical energy by a device comprising a sandwich of at least two semiconductor portions, each portion having a p-n junction with a characteristic energy gap, and the portions lattice matched to one another by an intervening superlattice structure. This superlattice acts to block propagation into the next deposited portion of those dislocation defects which can form due to lattice mismatch between adjacent portions.

Blakeslee, A.E.; Mitchell, K.W.

1980-03-25T23:59:59.000Z

324

Device for conversion of electromagnetic radiation into electrical current  

DOE Patents (OSTI)

Electromagnetic energy may be converted directly into electrical energy by a device comprising a sandwich of at least two semiconductor portions, each portion having a p-n junction with a characteristic energy gap, and the portions lattice matched to one another by an intervening superlattice structure. This superlattice acts to block propagation into the next deposited portion of those dislocation defects which can form due to lattice mismatch between adjacent portions.

Blakeslee, A. Eugene (Golden, CO); Mitchell, Kim W. (Indian Hill, CO)

1981-01-01T23:59:59.000Z

325

CRC handbook of biological effects of electromagnetic fields  

Science Conference Proceedings (OSTI)

This book presents the current knowledge about the effects of electromagnetic fields on living matter. The three-part format covers dielectric permittivity and electrical conductivity of biological materials; effects of direct current and low frequency fields; and effects of radio frequency (including microwave) fields. The parts are designed to be consulted independently or in sequence, depending upon the needs of the reader. Useful appendixes on measurement units and safety standards are also included.

Polk, C.; Postow, E.

1986-01-01T23:59:59.000Z

326

CRC handbook of biological effects of electromagnetic fields  

Science Conference Proceedings (OSTI)

This book presents current knowledge about the effects of electromagnetic fields on living matter. The three-part format covers: dielectric permittivity and electrical conductivity of biological materials; effects of direct current and low frequency fields; and effects of radio frequency (including microwave) fields. The parts are designed to be consulted independently or in sequence, depending upon the needs of the reader. Useful appendixes on measurement units and safety standards are also included.

Polk, C. (Rhode Island Univ., Kingston, RI (United States). Dept. of Electrical Engineering); Postow, E. (National Naval Medical Center, Bethesda, MD (United States))

1986-01-01T23:59:59.000Z

327

Correlated Quantum Memory: Manipulating Atomic Entanglement via Electromagnetically Induced Transparency  

E-Print Network (OSTI)

We propose a feasible scheme of quantum state storage and manipulation via electromagnetically induced transparency (EIT) in flexibly $united$ multi-ensembles of three-level atoms. For different atomic array configurations, one can properly steer the signal and the control lights to generate different forms of atomic entanglement within the framework of linear optics. These results shed new light on designing the versatile quantum memory devices by using, e.g., an atomic grid.

H. Jing; X. -J. Liu; M. -L. Ge; M. -S. Zhan

2004-10-05T23:59:59.000Z

328

Photoelectron emission from LiF surfaces by ultrashort electromagnetic pulses  

Science Conference Proceedings (OSTI)

Energy- and angle-resolved electron emission spectra produced by incidence of ultrashort electromagnetic pulses on a LiF(001) surface are studied by employing a distorted-wave method named the crystal surface-Volkov (CSV) approximation. The theory makes use of the Volkov phase to describe the action of the external electric field on the emitted electron, while the electron-surface interaction is represented within the tight-binding model. The CSV approach is applied to investigate the effects introduced by the crystal lattice when the electric field is oriented parallel to the surface plane. These effects are essentially governed by the vector potential of the external field, while the influence of the crystal orientation was found to be negligible.

Acuna, M. A. [Instituto de Astronomia y Fisica del Espacio, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Universidad de Buenos Aires, Buenos Aires (Argentina); Gravielle, M. S. [Instituto de Astronomia y Fisica del Espacio, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Universidad de Buenos Aires, Buenos Aires (Argentina); Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina)

2011-03-15T23:59:59.000Z

329

Potential field and electromagnetic studies: Introduction  

DOE Green Energy (OSTI)

Several aeromagnetic surveys have been flown over Long Valley at different altitudes and line spacings. The one most often referred to was a high level (4 km or 13,200 feet above sea level barometric survey) flown by the USGS in 1973 along E-W lines spaced 1.7 km apart. Investigators attempted a quantitative interpretation of the data, and suggested that extensive post-caldera hydrothermal activity may have drastically altered the composition of the titanomagnetites in the Bishop Tuff, causing the magnetic low in the area of the resurgent dome. Others have reported in informal conversations, as is now supported by holes M-1 and 44-016, that the low in the western part of the caldera is the result of lower magnetization of the post-caldera volcanics and a large wedge of Paleozoic metasediments that floor the caldera. The true nature of the magnetic high on the eastern flank of the resurgent dome has been revealed by recent paleomagnetic work and from a detailed aeromagnetic survey flown 400 feet above terrain for the USGS in 1979. 6 refs., 2 figs.

Goldstein, N.E.

1987-03-01T23:59:59.000Z

330

Model for nonlinear evolution of localized ion ring beam in magnetoplasma  

SciTech Connect

An electrostatic hybrid model, which investigates the nonlinear evolution of a localized ion ring beam in a magnetoplasma, is described and applied to the generation and evolution of turbulence in the very low frequency (VLF) ({Omega}{sub ci}<{omega}<{Omega}{sub ce}) range, where {Omega}{sub ci(e)} is the ion (electron) gyro frequency. Electrons are treated as a fluid and the ions with the particle-in-cell method. Although the model is electrostatic, it includes the effects of energy loss by convection of electromagnetic VLF waves out of the instability region by utilizing a phenomenological model for effective collisions with the fluid electrons. In comparison with a more conventional electrostatic hybrid model, the new model shows much more efficient extraction of energy from the ion ring beam and reduced background plasma heating over a range of parameters.

Scales, W. A. [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061-0111 (United States); Ganguli, G.; Mithaiwala, M. [Plasma Physics Division, Naval Research Laboratory, Washington D.C. 20375 (United States); Rudakov, L. [Icarus Research, Inc., P.O. Box 30780, Bethesda, Maryland 20824-0780 (United States)

2012-06-15T23:59:59.000Z

331

A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano,  

Open Energy Info (EERE)

A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano, A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano, Hawaii Jump to: navigation, search OpenEI Reference LibraryAdd to library == A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano, HawaiiThesis/Dissertation == Author Catherine King Skokan Organization Colorado School of Mines Published Publisher Not Provided, 1974 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano, Hawaii Citation [[Citation::Catherine King Skokan. 1974. A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano, Hawaii []. [ (!) ]: Colorado School of Mines.]] Retrieved from "http://en.openei.org/w/index.php?title=A_Time-Domain_Electromagnetic_Survey_of_the_East_Rift_Zone_Kilauea_Volcano,_Hawaii&oldid=682585"

332

DEVELOPMENT OF A FAST-RELEASE ELECTRO-MAGNET FOR POOL-TYPE RESEARCH REACTORS  

SciTech Connect

Experimental data and observations of the design parameters and physical configurations which lead to faster-release cylindrical flat-faced electromagnets are given. Detailed drawings and operating characteristics are presented for an electromagnet suited to the requirements of a pool-type research reactor using either gravity drop or additional accelerating force. This electromagnet embodies the experimentally developed techniques for attaining fast release. (auth)

Michelson, C.

1958-02-14T23:59:59.000Z

333

Three dimensional interpretations of single-well electromagnetic data for geothermal applications  

E-Print Network (OSTI)

Energy, Office of Wind and Geothermal Technologies of theTwenty-Ninth Workshop on Geothermal Reservoir EngineeringELECTROMAGNETIC DATA FOR GEOTHERMAL APPLICATIONS Hung-Wen

Tseng, Hung-Wen; Lee, Ki Ha

2004-01-01T23:59:59.000Z

334

Comment on Pion-nucleon bremsstrahlung and. Delta. electromagnetic moments''  

SciTech Connect

We analyze the definition of the electromagnetic moments of the dressed'' {Delta} introduced by Heller, Kumano, Martinez, and Moniz with respect to gauge invariance.

Weyrauch, M. (Department of Physics and Mathematical Physics, University of Adelaide, Adelaide, South Australia 5001 (AU))

1989-11-01T23:59:59.000Z

335

Effect of Electromagnetic Stirring on the Structure of Cast Al-4.5%Cu ...  

Science Conference Proceedings (OSTI)

Numerical Modeling of Centrifugally Cast HSS Rolls Numerical Simulation of Electro-magnetic Turbulent Inhibitor Technology in a Tundish Optimizing the...

336

Dyadic Green Function for an Electromagnetic Medium Inspired by General Relativity  

E-Print Network (OSTI)

The dyadic Green function for a homogeneous electromagnetic medium inspired by the spatiotemporally nonhomogeneous constitutive equations of gravitationally affected vacuum is derived.

Akhlesh Lakhtakia; Tom G. Mackay

2005-11-08T23:59:59.000Z

337

Experimental and Analytical Characterization of a Transducer for Energy Harvesting Through Electromagnetic Induction.  

E-Print Network (OSTI)

??Advances in mechatronics have renewed interest in the harvesting and storage of ambient vibration energy. This work documents recent efforts to model a novel electromagnetic (more)

Domme, Daniel Joseph

2008-01-01T23:59:59.000Z

338

Full-wave algorithms for model order reduction and electromagnet analysis of impedance and scattering  

E-Print Network (OSTI)

As technology advances and sophisticated electronic systems achieve ubiquity, the demand for thorough, efficient Electromagnetic (EM) analysis continues to rise. The prohibitive costs of constructing and maintaining ...

Klemas, Thomas J. (Thomas Jonas)

2005-01-01T23:59:59.000Z

339

On inverse scattering at high energies for the multidimensional Newton equation in electromagnetic field  

E-Print Network (OSTI)

We consider the multidimensional (nonrelativistic) Newton equation in a static electromagnetic field $$\\ddot x = F(x,\\dot x), F(x,\\dot x)=-\

Alexandre Jollivet

2007-09-29T23:59:59.000Z

340

TESTING GROUND BASED GEOPHYSICAL TECHNIQUES TO REFINE ELECTROMAGNETIC SURVEYS NORTH OF THE 300 AREA HANFORD WASHINGTON  

SciTech Connect

Airborne electromagnetic (AEM) surveys were flown during fiscal year (FY) 2008 within the 600 Area in an attempt to characterize the underlying subsurface and to aid in the closure and remediation design study goals for the 200-PO-1 Groundwater Operable Unit (OU). The rationale for using the AEM surveys was that airborne surveys can cover large areas rapidly at relatively low costs with minimal cultural impact, and observed geo-electrical anomalies could be correlated with important subsurface geologic and hydrogeologic features. Initial interpretation of the AEM surveys indicated a tenuous correlation with the underlying geology, from which several anomalous zones likely associated with channels/erosional features incised into the Ringold units were identified near the River Corridor. Preliminary modeling resulted in a slightly improved correlation but revealed that more information was required to constrain the modeling (SGW-39674, Airborne Electromagnetic Survey Report, 200-PO-1 Groundwater Operable Unit, 600 Area, Hanford Site). Both time-and frequency domain AEM surveys were collected with the densest coverage occurring adjacent to the Columbia River Corridor. Time domain surveys targeted deeper subsurface features (e.g., top-of-basalt) and were acquired using the HeliGEOTEM{reg_sign} system along north-south flight lines with a nominal 400 m (1,312 ft) spacing. The frequency domain RESOLVE system acquired electromagnetic (EM) data along tighter spaced (100 m [328 ft] and 200 m [656 ft]) north-south profiles in the eastern fifth of the 200-PO-1 Groundwater OU (immediately adjacent to the River Corridor). The overall goal of this study is to provide further quantification of the AEM survey results, using ground based geophysical methods, and to link results to the underlying geology and/or hydrogeology. Specific goals of this project are as follows: (1) Test ground based geophysical techniques for the efficacy in delineating underlying geology; (2) Use ground measurements to refine interpretations of AEM data; and (3) Improve the calibration and correlation of AEM information. The potential benefits of this project are as follows: (1) Develop a tool to map subsurface units at the Hanford Site in a rapid and cost effective manner; (2) Map groundwater pathways within the River Corridor; and (3) Aid development of the conceptual site model. If anomalies observed in the AEM data can be correlated with subsurface geology, then the rapid scanning and non-intrusive capabilities provided by the airborne surveys can be used at the Hanford Site to screen for areas that warrant further investigation.

PETERSEN SW

2010-12-02T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Modified definition of group velocity and electromagnetic energy conservation equation  

E-Print Network (OSTI)

The classical definition of group velocity has two flaws: (a) the group velocity can be greater than the phase velocity in a non-dispersive medium; (b) the definition is not consistent with the principle of relativity. To remove the flaws, a modified definition is proposed. A criterion is set up to identify the justification of group velocity definition. A "superluminal power flow" is constructed to show that the electromagnetic energy conservation equation cannot uniquely define the power flow if the principle of Fermat is not taken into account.

Changbiao Wang

2013-06-13T23:59:59.000Z

342

Surface moisture measurement system electromagnetic induction probe calibration technique  

SciTech Connect

The Surface Moisture Measurement System (SMMS) is designed to measure the moisture concentration near the surfaces of the wastes located in the Hanford Site tank farms. This document describes a calibration methodology to demonstrate that the Electromagnetic Induction (EMI) moisture probe meets relevant requirements in the `Design Requirements Document (DRD) for the Surface Moisture Measurement System.` The primary purpose of the experimental tests described in this methodology is to make possible interpretation of EMI in-tank surface probe data to estimate the surface moisture.

Crowe, R.D., Westinghouse Hanford

1996-07-08T23:59:59.000Z

343

Unusual formations of the free electromagnetic field in vacuum  

E-Print Network (OSTI)

It is shown that there are exact solutions of the free Maxwell equations (FME) in vacuum allowing an existence of stable spherical formations of the free magnetic field and ring-like formations of the free electric field. It is detected that a form of these spheres and rings does not change with time in vacuum. It is shown that these convergent solutions are the result of an interference of some divergent solutions of FME. One can surmise that these electromagnetic formations correspond to Kapitsa's hypothesis about interference origin and a structure of fireball.

Andrew E. Chubykalo; Augusto Espinoza

2005-03-25T23:59:59.000Z

344

Interference effects in the reradiation of ultrashort electromagnetic pulses  

E-Print Network (OSTI)

Reradiation of a spatially non-uniform ultrashort electromagnetic pulse interacting with the linear chain of multielectron atoms is studied in the framework of sudden perturbation approximation. Angular distributions of the reradiation spectrum for arbitrary number of atoms are obtained. It is shown that interference effects for the photon radiation amplitudes lead to appearing of "diffraction" maximums. The obtained results can be extended to the case of two- and three-dimensional crystal lattices and atomic chains. The approach developed allows also to take into account thermal vibrations of the lattice atoms.

Matveev, V I

2012-01-01T23:59:59.000Z

345

Customer Electromagnetic Compatibility: A Study on Interference Issues  

Science Conference Proceedings (OSTI)

Electromagnetic compatibility (EMC) has been a problem since before the invention of radio. The proliferation of ever-more sensitive electronic devices has made EMC and RFI into quite pervasive problems. When confronted with an interference problem, it is easy and tempting to automatically blame the electric power company or the radio amateur next door, but in fact the source may be right in the interference recipient's own home. Or, because of the long-distance propagation of radio waves, it may turn ou...

2004-12-20T23:59:59.000Z

346

Interference effects in the reradiation of ultrashort electromagnetic pulses  

E-Print Network (OSTI)

Reradiation of a spatially non-uniform ultrashort electromagnetic pulse interacting with the linear chain of multielectron atoms is studied in the framework of sudden perturbation approximation. Angular distributions of the reradiation spectrum for arbitrary number of atoms are obtained. It is shown that interference effects for the photon radiation amplitudes lead to appearing of "diffraction" maximums. The obtained results can be extended to the case of two- and three-dimensional crystal lattices and atomic chains. The approach developed allows also to take into account thermal vibrations of the lattice atoms.

V. I. Matveev; D. U. Matrasulov

2012-05-20T23:59:59.000Z

347

Electromagnetic wave method for mapping subterranean earth formations  

SciTech Connect

The present invention is directed to a method for remotely mapping subterranean coal beds prior to and during in situ gasification operations. This method is achieved by emplacing highly directional electromagnetic wave transmitters and receivers in bore holes penetrating the coal beds and then mapping the anomalies surrounding each bore hole by selectively rotating and vertically displacing the directional transmitter in a transmitting mode within the bore hole, and thereafter, initiating the gasification of the coal at bore holes separate from those containing the transmitters and receivers and then utilizing the latter for monitoring the burn front as it progresses toward the transmitters and receivers.

Shuck, Lowell Z. (Morgantown, WV); Fasching, George E. (Morgantown, WV); Balanis, Constantine A. (Morgantown, WV)

1977-01-01T23:59:59.000Z

348

Super-light electromagnetic wave with longitudinal and transversal modes  

E-Print Network (OSTI)

The transformation converting equations invariant under Lorentz into the equations invariant under Galileo is obtained. On this basis: (1) the super-light electromagnetic wave with longitudinal and transversal modes is found out; (2) it is shown the wave velocity coincides with that of de Broglie's wave; (3) the connection between Maxwell's electrodynamics and Shredinger's equation is established; (4) structural elements of space are discovered and "a horizon of visibility" is found. It is shown Bell's inequalities and the principle of the light speed constancy are based on the SRT artifact and "Einstein's local realism" is determined by the wave referred above. Objectivity of results for quantum and classical objects is discussed

M. M. Kononenko

2007-08-20T23:59:59.000Z

349

Detection of electromagnetic radiation using micromechanical multiple quantum wells structures  

DOE Patents (OSTI)

An apparatus and method for detecting electromagnetic radiation employs a deflectable micromechanical apparatus incorporating multiple quantum wells structures. When photons strike the quantum-well structure, physical stresses are created within the sensor, similar to a "bimetallic effect." The stresses cause the sensor to bend. The extent of deflection of the sensor can be measured through any of a variety of conventional means to provide a measurement of the photons striking the sensor. A large number of such sensors can be arranged in a two-dimensional array to provide imaging capability.

Datskos, Panagiotis G [Knoxville, TN; Rajic, Slobodan [Knoxville, TN; Datskou, Irene [Knoxville, TN

2007-07-17T23:59:59.000Z

350

Electromagnetic Interference and the Pacemaker Patient T1-Electromagnetic Interference and the Pacemaker Patient 10/03/03  

E-Print Network (OSTI)

While clinically significant problems with electromagnetic interference (EMI) are rare, a pacemakers response to EMI becomes more diverse as technology advances. Pacemaker manufacturers continue to develop interference protection circuitry to keep up with these vast sources of EMI. The pacemakers response to EMI is dependent on the characteristics of the EMI, proximity to the interference, available shielding, and the sensing characteristics and polarity of the pacemaker. The pacemaker circuitry is designed to attenuate any interference outside the normal intracardiac range (10 Hz 100 Hz). This is achieved by using bandpass filters. EMI sources can be broadly classified as galvanic, electromagnetic or magnetic. Galvanic interference requires direct contact with electrical current. This is most often seen in defibrillation/cardioversion, cautery, TENS units and diathermy. Electromagnetic or electrically coupled interference does not require direct body contact. This interference is most often seen with arc welders, ham radios, electrical appliances, metal detectors, therapeutic ultrasound and high voltage power lines. Magnetic interference occurs when a patient comes in close proximity with an intense magnetic field. This is often seen in nuclear magnetic resonance imaging (NMR/MRI) and steel mill induction furnaces. EMI with signal modulation can mimic normal intracardiac signals. When detected, the response to EMI may present itself as a single beat inhibition, total inhibition, noise reversion/asynchronous pacing, rate increase, erratic pacing, or no output. These responses are usually temporary, but can be permanent if the pulse generator circuitry is damaged. A pacemakers response to EMI is highly dependent on the specific EMI source, the pacemakers mode, and sensing polarity. Included is a list that details the interaction of commonly encountered pacemaker EMI sources. Accompanying this list is a summary table of these sources and reported associated pacemaker responses.

Rev A

1998-01-01T23:59:59.000Z

351

Testing Loop Quantum Gravity and Electromagnetic Dark Energy in Superconductors  

E-Print Network (OSTI)

In 1989 Cabrera and Tate reported an anomalous excess of mass of the Cooper pairs in rotating thin Niobium rings. So far, this experimental result never received a proper theoretical explanation in the context of superconductor's physics. In the present work we argue that what Cabrera and Tate interpreted as an anomalous excess of mass can also be associated with a deviation from the classical gravitomagnetic Larmor theorem due to the presence of dark energy in the superconductor, as well as with the discrete structure of the area of the superconducting Niobium ring as predicted by Loop Quantum Gravity. From Cabrera and Tate measurements we deduce that the quantization of spacetime in superconducting circular rings occurs at the Planck-Einstein scale $l_{PE} = (\\hbar G/c^3 \\Lambda)^{1/4}\\sim 3.77\\times 10 ^{-5} m$, instead of the Planck scale $l_{P} =(\\hbar G / c^3)^{1/2}=1.61 \\times 10 ^{-35} m$, with an Immirzi parameter which depends on the specific critical temperature of the superconducting material and on the area of the ring. The stephan-Boltzmann law for quantized areas delimited by superconducting rings is predicted, and an experimental concept based on the electromagnetic black-body radiation emitted by this surfaces, is proposed to test loop quantum gravity and electromagnetic dark energy in superconductors.

Clovis Jacinto de Matos

2008-12-30T23:59:59.000Z

352

On the Time Reversal Invariance of Classical Electromagnetic Theory  

E-Print Network (OSTI)

David Albert claims that classical electromagnetic theory is not time reversal invariant. He acknowledges that all physics books say that it is, but claims they are "simply wrong" because they rely on an incorrect account of how the time reversal operator acts on magnetic fields. On that account, electric fields are left intact by the operator, but magnetic fields are inverted. Albert sees no reason for the asymmetric treatment, and insists that neither field should be inverted. I argue, to the contrary, that the inversion of magnetic fields makes good sense and is, in fact, forced by elementary geometric considerations. I also suggest a way of thinking about the time reversal invariance of classical electromagnetic theory -- one that makes use of the invariant four-dimensional formulation of the theory -- that makes no reference to magnetic fields at all. It is my hope that it will be of interest in its own right, Albert aside. It has the advantage that it allows for arbitrary curvature in the background spacetime structure, and is therefore suitable for the framework of general relativity. The only assumption one needs is temporal orientability.

David B. Malament

2003-12-18T23:59:59.000Z

353

Intense Electromagnetic Outbursts from Collapsing Hypermassive Neutron Stars  

E-Print Network (OSTI)

We study the gravitational collapse of a magnetized neutron star using a novel numerical approach able to capture both the dynamics of the star and the behavior of the surrounding plasma. In this approach, a fully general relativistic magnetohydrodynamics implementation models the collapse of the star and provides appropriate boundary conditions to a force-free model which describes the stellar exterior. We validate this strategy by comparing with known results for the rotating monopole and aligned rotator solutions and then apply it to study both rotating and non-rotating stellar collapse scenarios, and contrast the behavior with what is obtained when employing the electrovacuum approximation outside the star. The non-rotating electrovacuum collapse is shown to agree qualitatively with a Newtonian model of the electromagnetic field outside a collapsing star. We illustrate and discuss a fundamental difference between the force-free and electrovacuum solutions, involving the appearance of large zones of electric-dominated field in the vacuum case. This provides a clear demonstration of how dissipative singularities appear generically in the non-linear time-evolution of force-free fluids. In both the rotating and non-rotating cases, our simulations indicate that the collapse induces a strong electromagnetic transient. In the case of sub-millisecond rotation, the magnetic field experiences strong winding and the transient carries much more energy. This result has important implications for models of gamma-ray bursts.

Luis Lehner; Carlos Palenzuela; Steven L. Liebling; Christopher Thompson; Chad Hanna

2011-12-12T23:59:59.000Z

354

Magnetic resonance as a channel of directed transmission of electromagnetic energy in animate nature  

E-Print Network (OSTI)

The phenomenon of magnetic resonance (either NMR or ESR) is a responce of atomic (molecular) system to the external electromagnetic effect. Electrons and nuclei, which possess magnetic moment, are the "magnetic antennas" in the biosystem "human being". They are able to receive (radiate) electromagnetic energy selectively in coordinates $H$ (magnetic field), $\

E. Ya. Fursa

2002-12-09T23:59:59.000Z

355

ccsd00001714, Nonlinear dynamics of electromagnetic pulses in cold relativistic plasmas  

E-Print Network (OSTI)

ccsd­00001714, version 2 ­ 19 Oct 2004 Nonlinear dynamics of electromagnetic pulses in cold particle and photon accel- eration, nonlinear optics, laser fusion, and others [1{6]. Intense of coupled electromagnetic and electrostatic modes in cold relativistic electron-ion plas- mas to conclude

356

Brief paper: Controlling the motion of charged particles in a vacuum electromagnetic field from the boundary  

Science Conference Proceedings (OSTI)

We consider the problem of driving two non-relativistic charged particles in a bounded vacuum electromagnetic field to the same location by applying electromagnetic forces through the boundary of the domain. The dynamics of the particles is modeled by ... Keywords: Boundary feedback, Charged particle, Maxwell-Lorentz system, Nuclear fusion, Perturbed energy

Luis R. Suazo; Weijiu Liu

2009-04-01T23:59:59.000Z

357

Handbook for Electromagnetic Compatibility of Digital Equipment in Power Plants, Volume 1  

Science Conference Proceedings (OSTI)

The two volumes of this handbook explain the fundamentals of electromagnetic compatibility and provides guidelines for ensuring the electromagnetic compatibility of digital equipment in power plants. The handbook is applicable to digital equipment being installed in all types of power plants.

1994-10-01T23:59:59.000Z

358

Handbook for Electromagnetic Compatibility of Digital Equipment in Power Plants, Volume 2  

Science Conference Proceedings (OSTI)

The two volumes of this handbook explain the fundamentals of electromagnetic compatibility and provides guidelines for ensuring the electromagnetic compatibility of digital equipment in power plants. The handbook is applicable to digital equipment being installed in all types of power plants.

1994-10-01T23:59:59.000Z

359

A revised electromagnetism-like mechanism for layout design of reconfigurable manufacturing system  

Science Conference Proceedings (OSTI)

The layout design problem is one of the most important issues for manufacturing system design and control. A revised electromagnetism-like mechanism (REM) is proposed in this paper for the layout design of reconfigurable manufacturing systems utilizing ... Keywords: Automated guided vehicle, Electromagnetism-like mechanism, Layout design, Variable neighbourhood search

Xianping Guan; Xianzhong Dai; Baijing Qiu; Jun Li

2012-08-01T23:59:59.000Z

360

Automatic collecting technique of low frequency electromagnetic signals and its application in earthquake study  

Science Conference Proceedings (OSTI)

Two methods to automatically collect disturbed ultra low frequency electromagnetic signals before strong earthquakes were developed in this paper, in which one is only related to the spectrum intensity of electric field, and another is additionally combined ... Keywords: Chile earthquake, DEMETER, fractal property, multi parameters, ultra low frequency electromagnetic emission

Xuemin Zhang; Roberto Battiston; Xuhui Shen; Zhima Zeren; Xinyan Ouyang; Jiadong Qian; Jing Liu; Jianping Huang; Yuanqing Miao

2010-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Model reference adaptive temperature control of the electromagnetic oven process in manufacturing process  

Science Conference Proceedings (OSTI)

Nowadays, the electromagnetic ovens are used for heating the component assembly of electronic manufacturing. The control systems of the electromagnetic ovens are feedback control system and PID controller are used to control their temperature. This process ... Keywords: control theory, response optimization and model reference adaptive system

Jiraphon Srisertpol; Supot Phungphimai

2010-02-01T23:59:59.000Z

362

A fast multigrid-based electromagnetic eigensolver for curved metal boundaries on the Yee mesh  

Science Conference Proceedings (OSTI)

For embedded boundary electromagnetics using the Dey-Mittra (Dey and Mittra, 1997) [1] algorithm, a special grad-div matrix constructed in this work allows use of multigrid methods for efficient inversion of Maxwell's curl-curl matrix. Efficient curl-curl ... Keywords: Accelerator, Algorithm, Cavity, Dey, Eigensolver, Electromagnetics, Finite difference, Maxwell, Mittra, Multigrid, Yee

Carl A. Bauer, Gregory R. Werner, John R. Cary

2013-10-01T23:59:59.000Z

363

Path planning and position control and of an underactued [sic] electromagnetic formation flight satellite system in the near field  

E-Print Network (OSTI)

Electromagnetic formation flight is the process of using electromagnetic actuators (coils) on multiple spacecraft to produce relative (internal) forces in order to control the relative position and orientation of the ...

Buck, Alexander J. (Alexander James), 1989-

2013-01-01T23:59:59.000Z

364

Planning for coordinated space and ground-based ionospheric modification experiments  

SciTech Connect

The planning and conducting of coordinated space and ground-based ionospheric modification experiments are discussed. The purpose of these experiments is to investigate (1) the nonlinear VLF wave interaction with the ionospheric plasmas, and (2) the nonlinear propagation of VLF waves in the HF-modified ionosphere. It is expected that the HY-induced ionospheric density striations can render the nonlinear mode conversion of VLF waves into lower hybrid waves. Lower hybrid waves can also be excited parametrically by the VLF waves in the absence of the density striations if the VLF waves are intense enough. Laboratory experiments are planned for crosschecking the results obtained from the field experiments.

Lee, M.C.

1990-10-01T23:59:59.000Z

365

Time-Domain Electromagnetics At Soda Lake Area (Combs 2006) | Open Energy  

Open Energy Info (EERE)

Time-Domain Electromagnetics At Soda Lake Area (Combs 2006) Time-Domain Electromagnetics At Soda Lake Area (Combs 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Time-Domain Electromagnetics At Soda Lake Area (Combs 2006) Exploration Activity Details Location Soda Lake Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness not indicated DOE-funding Unknown Notes "EM sounding, MT, CSAMT, dipole-dipole resistivity; reservoir model?" References Jim Combs (1 January 2006) Historical Exploration And Drilling Data From Geothermal Prospects And Power Generation Projects In The Western United States Retrieved from "http://en.openei.org/w/index.php?title=Time-Domain_Electromagnetics_At_Soda_Lake_Area_(Combs_2006)&oldid=388133" Category:

366

Questions and Answers - I am creating an electromagnet for my school's  

NLE Websites -- All DOE Office Websites (Extended Search)

Do you know whatan electromagnet is? Do you know what<br>an electromagnet is? Previous Question (Do you know what an electromagnet is?) Questions and Answers Main Index Next Question (Why does adding coils to an electromagnet make it stronger?) Why does adding coils to anelectromagnet make it stronger? I am creating an electromagnet for my school's science fair project. Does the shape of the iron core make a difference? Is solid copper wire better than stranded wire? Is copper wire best, or is another wire better? Should the wire be insulated or bare? What can I do to get the most current out of a battery? Yes, the shape of the iron core does matter. The more complete the circuit formed by the iron, the more field that you will get for a given coil and current. The best way to do a simple magnet is to have an iron core shaped

367

Is it possible to create a quantum electromagnetic "black hole" at the Large Hadron Collider?  

E-Print Network (OSTI)

As demonstrated by Chernodub, strong magnetic field forces vacuum to develop real condensates of electrically charged rho mesons, which form an anisotropic inhomogeneous superconducting state similar to Abrikosov vortex lattice. As far as electromagnetic field behaviour is concerned, this state of vacuum constitutes a hyperbolic metamaterial [1]. Here we demonstrate that spatial variations of magnetic field may lead to formation of electromagnetic "black holes" inside this metamaterial. Similar to real black holes, horizon area of the electromagnetic "black holes" is quantized in units of the effective "Planck scale" squared. The magnetic fields of the required strength and geometrical configuration may be created on Earth in heavy-ion collisions at the Large Hadron Collider. We evaluate electromagnetic field distribution around an electromagnetic "black hole" which may be created as a result of such collision.

Igor I. Smolyaninov

2012-04-04T23:59:59.000Z

368

Evidences of regulatory and signalling role of electromagnetic fields in biological objects: review of literature and own studies  

Science Conference Proceedings (OSTI)

There are growing evidence supporting the role of electromagnetic fields and interactions in biological processes. In this paper we're trying to theoretically substantiate the feasibility and necessity of the "Theory of Electromagnetic Biological Regulation ... Keywords: antibodies, biological regulation, cell, electromagnetic field, signalling, viruses

Valeriy Zaporozhan; Andriy Ponomarenko

2008-12-01T23:59:59.000Z

369

A New Look on the Electromagnetic Duality. Suggestions and Developments  

E-Print Network (OSTI)

In this paper a new look on the electro-magnetic duality is presented and appropriately exploited. The duality analysis in the nonrelativistic and relativistic formulations is shown to lead to the idea the mathematical model field to be a differential form valued in the 2-dimensional vector space ${\\cal R}^2$. A full ${\\cal R}^2$ covariance is achieved through introducing explicitly the canonical complex structure ${\\cal I}$ of ${\\cal R}^2$ in the nonrelativistic equations. The connection of the relativistic Hodge * with ${\\cal I}$ is shown and a complete coordinate free relativistic form of the equations and the conservative quantities is obtained. The duality symmetry is interpreted as invariance of the conservative quantities and conservation equations.

Donev, S

2000-01-01T23:59:59.000Z

370

A New Look on the Electromagnetic Duality. Suggestions and Developments  

E-Print Network (OSTI)

In this paper a new look on the electro-magnetic duality is presented and appropriately exploited. The duality analysis in the nonrelativistic and relativistic formulations is shown to lead to the idea the mathematical model field to be a differential form valued in the 2-dimensional vector space ${\\cal R}^2$. A full ${\\cal R}^2$ covariance is achieved through introducing explicitly the canonical complex structure ${\\cal I}$ of ${\\cal R}^2$ in the nonrelativistic equations. The connection of the relativistic Hodge * with ${\\cal I}$ is shown and a complete coordinate free relativistic form of the equations and the conservative quantities is obtained. The duality symmetry is interpreted as invariance of the conservative quantities and conservation equations.

Stoil Donev

2000-06-27T23:59:59.000Z

371

On Digital Radio Receiver Performance in Electromagnetic Interference Environments  

E-Print Network (OSTI)

adiated emission from electronic equipment, co-located to a digital radio receiver, can affect receiving performance. It is therefore of great importance that this undesired emission be considered in the early design phase of a system containing radio equipment. For this purpose, methods to estimate the performance degradation on digital radio receivers in such environment must be available. From a military point of view, such methods are necessary for at least two important situations; 1) The communication system is not subject to interference from hostile jammers. In this case, undesired electromagnetic interference will decrease the operating range of the radio link. 2) The communication system is subject to interference from hostile jammers. In this case, the ability to withstand jamming is degraded by the undesired interference, as the latter degrades the signal protection devices in the communication system. A tactical consequence of this is that the jammer can obtain the same ...

Peter Stenumgaard; Peter Stenumgaard; Isrn Kth/rst/r--/ --se

1999-01-01T23:59:59.000Z

372

Strong-field spatial interference in a tailored electromagnetic bath  

E-Print Network (OSTI)

Light scattered by a regular structure of atoms can exhibit interference signatures, similar to the classical double-slit. These first-order interferences, however, vanish for strong light intensities, restricting potential applications. Here, we show how to overcome these limitations to quantum interference in strong fields. First, we recover the first-order interference in strong fields via a tailored electromagnetic bath with a suitable frequency dependence. At strong driving, the optical properties for different spectral bands are distinct, thus extending the set of observables. We further show that for a two-photon detector as, e.g., in lithography, increasing the field intensity leads to twice the spatial resolution of the second-order interference pattern compared to the weak-field case.

M. Macovei; J. Evers; G. -x. Li; C. H. Keitel

2006-06-19T23:59:59.000Z

373

Electromagnetic Forces and Fields in a Rotating Reference Frame  

E-Print Network (OSTI)

Maxwells equations and the equations governing charged particle dynamics are presented for a rotating coordinate system with the global time coordinate of an observer on the rotational axis. Special care is taken in defining the relevant entities in these equations. Ambiguities in the definitions of the electromagnetic fields are pointed out, and in fact are shown to be essential in such a system of coordinates. The Lorentz force is found to have an extra term in this frame, which has its origins in relativistic mass. A related term in the energy equation, which allows inertia to be gained even during strict corotation, suggests ways existing pulsar magnetosphere models may be modified to match observed braking indices more closely. Subject headings: magnetic fields relativity pulsars: general 3

Paul N. Arendt

1998-01-01T23:59:59.000Z

374

Electromagnetic and Hadron Calorimeters in the MIPP Experiment  

E-Print Network (OSTI)

The purpose of the MIPP experiment is to study the inclusive production of photons, pions, kaons and nucleons in pi, K and p interactions on various targets using beams from the Main Injector at Fermilab. The function of the calorimeters is to measure the production of forward-going neutrons and photons. The electromagnetic calorimeter consist of 10 lead plates interspersed with proportional chambers. It was followed by the hadron calorimeter with 64 steel plates interspersed with scintillator. The data presented were collected with a variety of targets and beam momenta from 5 GeV/c to 120 GeV/c. The energy calibration of both calorimeters with electrons, pions, kaons, and protons is discussed. The resolution for electrons was found to be 0.27/sqrt(E), and for hadrons the resolution was 0.554/sqrt(E) with a constant term of 2.6%. The performance of the calorimeters was tested on a neutron sample.

T. S. Nigmanov; H. R. Gustafson; M. J. Longo; H. K. Park; D. Rajaram; C. Dukes; L. C. Lu; C. Materniak; K. Nelson; A. Norman; H. Meyer; A. Lebedev; S. Seun; N. Graf; J. M. Paley; G. Aydin; Y. Gunaydin; D. E. Miller

2009-03-13T23:59:59.000Z

375

Computer simulation of low-frequency electromagnetic data acquisition  

DOE Green Energy (OSTI)

Computer simulation of low frequency electromagnetic (LFEM) digital data acquisition in the presence of natural field noise demonstrates several important limitations and considerations. Without the use of a remote reference noise removal scheme it is difficult to obtain an adequate ratio of signal to noise below 0.1 Hz for frequency domain processing and below 0.3 Hz base frequency for time domain processing for a typical source-receiver configuration. A digital high-pass filter substantially facilitates rejection of natural field noise above these frequencies but, at lower frequencies where much longer stacking times are required, it becomes ineffective. Use of a remote reference to subtract natural field noise extends these low-frequency limits a decade, but this technique is limited by the resolution and dynamic range of the instrumentation. Gathering data in short segments so that natural field drift can be offset for each segment allows a higher gain setting to minimize dynamic range problems.

SanFilipo, W.A.; Hohmann, G.W.

1982-02-01T23:59:59.000Z

376

Low frequency electromagnetic prospecting system. [Grass Valley, KGRA  

DOE Green Energy (OSTI)

A prototype portable electromagnetic sounding system was assembled and depth sounding survey was conducted in Grass Valley, Nevada, as a part of a program to evaluate geophysical techniques in geothermal exploration. A horizontal loop transmitter of radius 50 meters operating between .01 Hz and 100 Hz was used in conjunction with a SQUID magnetometer. A digital synchronous detector was used for on site processing of magnetometer output. This detector allowed useful data acquisition with transmitter-receiver separation of up to 2 km with power requirements of less than 72 watts. Conductive sediments (1 to 10 ohm-m) of thicknesses of up to 1.5 km were well resolved with this system, and the interpreted sections compared very well with dc resistivity measurements made with much heavier equipment and larger arrays in the same area.

Jain, B.K.

1978-04-01T23:59:59.000Z

377

Relativistic electromagnetic flat top solitons and their stability  

Science Conference Proceedings (OSTI)

The inclusion of ion response in the study of relativistically intense electromagnetic laser pulse propagation in plasma yields certain distinct varieties of single peak solitonic structures. A flat top slow moving structure (for which the various fields have a flat profile over a wide spatial range) is one such solution. A detailed characterization of these solutions along with the eigen spectrum of their formation in the parameter space has been presented. The evolution of this particular solution is studied in detail with the help of a coupled fluid Maxwell set of equations. The study shows that the flat top solution is unstable. The instability is characterized as the backward Brillouin instability for which the electron quiver velocity plays the role of the effective temperature.

Sundar, Sita; Das, Amita; Saxena, Vikrant; Kaw, Predhiman; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)

2011-11-15T23:59:59.000Z

378

Electromagnetic valve for controlling the flow of molten, magnetic material  

DOE Patents (OSTI)

An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell.

Richter, Tomas (State College, PA)

1998-01-01T23:59:59.000Z

379

Electromagnetic valve for controlling the flow of molten, magnetic material  

DOE Patents (OSTI)

An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell. 5 figs.

Richter, T.

1998-06-16T23:59:59.000Z

380

Searching for electromagnetic counterparts of gravitational wave transients  

E-Print Network (OSTI)

A pioneering electromagnetic (EM) observation follow-up program of candidate gravitational wave (GW) triggers has been performed, Dec 17 2009 to Jan 8 2010 and Sep 4 to Oct 20 2010, during the recent LIGO/Virgo run. The follow-up program involved ground-based and space EM facilities observing the sky at optical, X-ray and radio wavelengths. The joint GW/EM observation study requires the development of specific image analysis procedures able to discriminate the possible EM counterpart of GW trigger from background events. The paper shows an overview of the EM follow-up program and the developing image analysis procedures as they are applied to data collected with TAROT and Zadko.

M. Branchesi; on behalf of the LIGO Scientific Collaboration; the Virgo Collaboration; A. Klotz; M. Laas-Bourez

2011-10-14T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Performance of the PrimEx Electromagnetic Calorimeter  

SciTech Connect

We report the design and performance of the hybrid electromagnetic calorimeter consisting of 1152 PbWO{sub 4} crystals and 576 lead glass blocks for the PrimEx experiment at the Jefferson Laboratory. The detector was built for high precision measurement of the neutral pion lifetime via the Primakoff effect. Calorimeter installation and commissioning was completed with the first physics run in fall of 2004. We present the energy and position resolution of the calorimeter. Obtained {pi}{sup 0} mass resolution of 1.3 MeV/c{sup 2} and its production angle resolution of 0.34 mrad demonstrate the ability of the experiment to extract the {pi}{sup 0} lifetime on one percent level.

M. Kubantsev; I. Larin; A. Gasparian

2006-06-05T23:59:59.000Z

382

Electromagnetic Compatibility from a Time-Frequency Perspective  

E-Print Network (OSTI)

Abstract In wireless communication, interference between two radio systems may occur when they operate at close frequency bands, sharing the same environment at the same time. Such systems coexist if both of them perform correctly in the presence of the other. To ensure their coexistence, Electromagnetic Compatibility (EMC) is used to specify rules within standardization bodies. According to current EMC standards, the radio spectrum has been divided into non-overlapping bands often with exclusive access. However, nowadays there is a proliferation of new digital systems sharing common frequency bands because the spectrum is a limited resource. Many of them are operating in unlicensed bands regulated by The International Telecommunications Union (ITU), for example the 2.45 GHz Industrial, Scientific and Medical (ISM) band. The frequency allocation is also changing with the emergence of digital systems and this is the case for white spaces in the broadcast television (TV) spectrum. To avoid high interference levels, it is necessary to consider some parameters related to signal variations, representing more accurately the environment. Some techniques have been proposed in the literature to reduce interference levels but they are applied to specific sharing studies. Hence, we evaluate in this paper the impact of time-frequency considerations for radio coexistence. We show that EMC studies are more precise and more representative of the reality when additional parameters relevant to the time domain are taken into account in the analysis framework. We illustrate these concepts through a specific study case. We evaluate the results for different system parameters, first considering that both of them occupy the same band and then assuming that they use overlapping but non-equal frequency bands. Index Terms Radio coexistence, electromagnetic compatibility, frequency-domain analysis, time-domain analysis.

Najett Neji; Raul De Lacerda; Alain Azoulay; Thierry Letertre

2013-01-01T23:59:59.000Z

383

Electromagnetic compatibility, tropospheric and ionospheric aspects of SPS MPTS operations  

DOE Green Energy (OSTI)

The results of a preliminary study of the effects of operation of a Solar Power Satellite (SPS) on the general performance of terrestrial and space based electromagnetic systems are given. In addition, the effects of a passing high energy Microwave Power Transmission System (MPTS) through the troposphere and through the ionosphere are also considered. The SPS as envisioned will be a satellite system in geosynchronous orbit with a solar array of about 144 square kilometers. The purpose of the SPS is to capture solar energy, convert the radiant energy to microwave energy and transmit it to the earth as a beam by means of a phased array antenna one kilometer in diameter at a frequency of 2.45 GHz. At the surface of the earth, the energy beam will be captured by an antenna about 100 square kilometers which will convert the microwave energy to high voltage ac power for injection into an electrical power network. The impact of SPS operation on the lower atmosphere, the ionosphere, and on operational telecommunication systems, is addressed in a preliminary manner. Topics include (a) further study on the susceptibility of electronic equipment to SPS emissions; (b) further study on the interference potential of SPS emissions and harmonics to electromagnetic systems; (c) study of the impact of tropospheric attenuation and scattering associated with SPS operation on microwave terrestrial, air/ground and satellite/ground telecommunication systems; (d) further theoretical study on the production of ionospheric irregularities resulting from microwave heating; and (e) further experimental evidence of the impact of SPS operation on the telecommunication system performance collected in conjunction with a Platteville microwave heating experiment.

Not Available

1978-03-01T23:59:59.000Z

384

Electromagnetic Analysis of ITER Diagnostic Equatorial Port Plugs During Plasma Disruptions  

Science Conference Proceedings (OSTI)

ITER diagnostic port plugs perform many functionsincluding structural support of diagnostic systems under high electromagnetic loads while allowing for diagnostic access to the plasma. The design of diagnostic equatorial port plugs (EPP) are largely driven by electromagnetic loads and associate responses of EPP structure during plasma disruptions and VDEs. This paper summarizes results of transient electromagnetic analysis using Opera 3d in support of the design activities for ITER diagnostic EPP. A complete distribution of disruption loads on the Diagnostic First Walls (DFWs), Diagnostic Shield Modules (DSMs) and the EPP structure, as well as impact on the system design integration due to electrical contact among various EPP structural components are discussed.

Y. Zhai, R. Feder, A. Brooks, M. Ulrickson, C.S. Pitcher and G.D. Loesser

2012-08-27T23:59:59.000Z

385

Effects of Detuning on Control of Intersubband Quantum Well Transitions with Chirped Electromagnetic Pulses  

Science Conference Proceedings (OSTI)

We study the interaction of a chirped electromagnetic pulse with intersubband transitions of a double semiconductor quantum well. We specifically consider the interaction of the ground and first excited subbands with the electromagnetic field and use the nonlinear density matrix equations for the description of the system dynamics. These equations are solved numerically for various values of the electron sheet density for a realistic double GaAs/AlGaAs quantum well, and the efficiency of population transfer is discussed with emphasis given to the effects of the detuning of the central frequency of the electromagnetic field from resonance.

Blekos, Konstantinos; Terzis, Andreas F. [Physics Department, School of Natural Sciences, University of Patras, Patras 265 04 (Greece); Simserides, Constantinos [Institute of Materials Science, National Center of Scientific Research Demokritos, 153 10 Athens (Greece); Paspalakis, Emmanuel [Materials Science Department, School of Natural Sciences, University of Patras, Patras 265 04 (Greece)

2010-11-10T23:59:59.000Z

386

Time-Domain Electromagnetics At Hualalai Northwest Rift Area (Thomas, 1986)  

Open Energy Info (EERE)

Time-Domain Electromagnetics At Hualalai Northwest Time-Domain Electromagnetics At Hualalai Northwest Rift Area (Thomas, 1986) Exploration Activity Details Location Hualalai Northwest Rift Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes Three time-domain electromagnetic soundings were conducted on the middle northwest rift at elevations of 280-320 m (Fig. 40) (Kauahikaua and Mattice, 1981). These soundings penetrated to a greater depth than the Schlumberger soundings and two of them were able to resolve basement resistivities ranging from 9 to 12 ohm-m at depths of 1500 to 1800 m. One sounding detected a 9 ohm.m layer at 600 m depth that was underlain by a more resistive basement. These results suggest that thermal fluids may be responsible for the low-resistivity basement, whereas the high-resistivity

387

Electromagnetic Casimir forces of parabolic cylinder and knife-edge geometries  

E-Print Network (OSTI)

An exact calculation of electromagnetic scattering from a perfectly conducting parabolic cylinder is employed to compute Casimir forces in several configurations. These include interactions between a parabolic cylinder and ...

Graham, Noah

388

Time-Domain Electromagnetics At Kilauea East Rift Area (Thomas, 1986) |  

Open Energy Info (EERE)

Time-Domain Electromagnetics At Kilauea East Rift Time-Domain Electromagnetics At Kilauea East Rift Area (Thomas, 1986) Exploration Activity Details Location Kilauea East Rift Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes A series of time-domain electromagnetic (TDEM) soundings were also performed in the lower East Rift Zone as part of the HGP exploration program (Klein and Kauahikaua, 1975; Kauahikaua and Klein, 1977); this work was recently expanded to include additional TDEM and vertical electrical soundings, and the entire data set was reinterpreted (Kauahikaua, 1981b; Kauahikaua and Mattice, 1981). The resistivity model presented by Kauahikaua (1981b) suggests that moderate to high basement resistivities, corresponding to cold freshwater saturated basalts, are present north of

389

Airborne Electromagnetic Survey At Chena Area (Erkan, Et. Al., 2008) | Open  

Open Energy Info (EERE)

Airborne Electromagnetic Survey At Chena Area (Erkan, Et. Al., 2008) Airborne Electromagnetic Survey At Chena Area (Erkan, Et. Al., 2008) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Airborne Electromagnetic Survey At Chena Area (Erkan, Et. Al., 2008) Exploration Activity Details Location Chena Geothermal Area Exploration Technique Airborne Electromagnetic Survey Activity Date 2008 Usefulness not indicated DOE-funding Unknown Notes The airborne resistivity (Fig. 2; panel c) shows high values in most of the areas including the Chena pluton, with the exception of the very northern and southern portion of the map where the Paleozoic metamorphic unit is located. Lineations of low resistivity at the west end of the area are generally associated with the location of the valley fill. However, some

390

Three-Dimensional Electromagnetic Particle-in-Cell Code Using High Performance Fortran on PC Cluster  

Science Conference Proceedings (OSTI)

A three-dimensional full electromagnetic particle-in-cell (PIC) code, TRISTAN (Tridimensional Stanford) code, has been parallelized using High Performance Fortran (HPF) as a RPM (Real Parallel Machine). In the simulation, the simulation domains are decomposed ...

DongSheng Cai; Yaoting Li; Ken-ichi Nishikawa; Chiejie Xiao; Xiaoyan Yan

2002-05-01T23:59:59.000Z

391

Electromagnetic wave scattering by discrete random media with remote sensing applications  

E-Print Network (OSTI)

The scattering of electromagnetic waves in medium with randomly distributed discrete scatterers is studied. Analytical and numerical solutions to several problems with implications for the active and passive remote sensing ...

Ao, Chi On, 1970-

2001-01-01T23:59:59.000Z

392

Design of a high-speed, meso-scale nanopositioners driven by electromagnetic actuators  

E-Print Network (OSTI)

The purpose of this thesis is to generate the design and fabrication knowledge that is required to engineer high-speed, six-axis, meso-scale nanopositioners that are driven by electromagnetic actuators. When compared to ...

Golda, Dariusz, 1979-

2008-01-01T23:59:59.000Z

393

Understanding quantum polarized-light interference experiments through electromagnetic energy flow lines  

E-Print Network (OSTI)

General expressions to obtain the electromagnetic energy flow lines behind interference gratings are derived in the case where the incident light consists of a polarized monochromatic plane wave. These flow lines show how the electromagnetic energy redistributes in space (behind the grating) until the Fraunhofer regime is reached, thus providing an interpretation based on photon paths for the physics underlying interference phenomena with light. Within this interpretation, one finds that the outcome from a Young's experiment is related in a simple manner to how the electromagnetic energy flux is influenced by the experimental setup, specifically, how the presence of polarizers on each slit and the boundaries imposed by having one or both slits open affect at each time the electromagnetic energy flow, which is directly linked to the Arago-Fresnel laws.

Sanz, A S; Bozic, M; Miret-Arts, S

2009-01-01T23:59:59.000Z

394

Electromagnetically-driven ultra-fast tool servos for diamond turning  

E-Print Network (OSTI)

This thesis presents the design, implementation, and control of a new class of fast tool servos (FTS). The primary thesis contributions include the design and experimental demonstration of: novel ultra-fast electromagnetic ...

Lu, Xiaodong, Ph. D. Massachusetts Institute of Technology

2005-01-01T23:59:59.000Z

395

A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea...  

Open Energy Info (EERE)

1974 DOI Not Provided Check for DOI availability: http:crossref.org Online Internet link for A Time-Domain Electromagnetic Survey of the East Rift Zone Kilauea Volcano,...

396

Plenary lecture I: electromagnetic low frequency radiation from natural phenomena - data analysis and modelling  

Science Conference Proceedings (OSTI)

Can severe weather conditions, volcanic eruptions or even earthquakes be predicted from monitoring and analyzing electromagnetic radiation especially in very and ultra low frequency ranges? What signatures in this frequency range leave solar wind, solar ...

Ernst D. Schmitter

2008-07-01T23:59:59.000Z

397

Improper Rotations'Symmetry of Electromagnetic Field and New Conserved Quantity of Complex Fields  

E-Print Network (OSTI)

It is established the partition of linear space $$ over the field of genuine scalars and pseudoscalars, the vectors in which are sets of contravariant and covariant electromagnetic field tensors and pseudotensors $F^{\\mu\

Yearchuck, D

2009-01-01T23:59:59.000Z

398

An Intercomparison Study Using Electromagnetic Three-Component Turbulent Velocity Probes  

Science Conference Proceedings (OSTI)

An intercomparison study was performed with four Russian-made, electromagnetic probes capable of measuring three components of oceanic turbulent velocities and two single-axis velocity sensors familiar to western scientists, namely, a hot-film ...

David Y. Lai; Vadim T. Paka; Donald P. Delisi; Anatoli V. Arjannikov; Sergei A. Khanaev

2000-07-01T23:59:59.000Z

399

Phenomenon of parametric trapping of electromagnetic waves in an inhomogeneous plasma  

SciTech Connect

A theory is developed of absolute parametric aperiodic instability in a spatially inhomogeneous plasma, when the electromagnetic waves generated in the plasma are trapped by the plasma near the peaks of the pumping-wave field.

Silin, V.P.; Starodub, A.N.

1977-10-01T23:59:59.000Z

400

Numerical methods for electromagnetic wave propagation and scattering in complex media  

E-Print Network (OSTI)

Numerical methods are developed to study various applications in electromagnetic wave propagation and scattering. Analytical methods are used where possible to enhance the efficiency, accuracy, and applicability of the ...

Moss, Christopher D. Q. (Christopher Doniert Q.), 1973-

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Visualizing electromagnetic field and particle simulations in accelerators with ParaView  

Science Conference Proceedings (OSTI)

SLAC performs large-scale simulations of Electromagnetic fields and particles for accelerator applications. These simulations run on intricate high order finite element meshes and produce field strengths spanning tens of orders of magnitudes. Such simulations ...

Greg L. Schussman

2009-11-01T23:59:59.000Z

402

An Electromagnetic Vorticity and Velocity Sensor for Observing Finescale Kinetic Fluctuations in the Ocean  

Science Conference Proceedings (OSTI)

An instrument has been developed that measures finescale velocity and vorticity in seawater based on the principles of motional induction. This instrument, the electromagnetic vorticity meter (EMVM), measures components of the gradient and ...

Thomas B. Sanford; James A. Carlson; John H. Dunlap; Mark D. Prater; Ren-Chieh Lien

1999-11-01T23:59:59.000Z

403

Electrically insulating phosphate coatings for iron powder based electromagnetic core applications  

E-Print Network (OSTI)

Powdered metals, such as iron, are a common building block for electromagnetic cores. An iron powder was reacted with phosphoric acid to create a layer of iron phosphate on each particle. This electrically insulating ...

Nolan, William Rane

2009-01-01T23:59:59.000Z

404

Gustav Mie and the Evolving Discipline of Electromagnetic Scattering by Particles  

Science Conference Proceedings (OSTI)

The year 2008 marks the centenary of the seminal paper by Gustav Mie on electromagnetic scattering by homogeneous spherical particles. Having been cited in almost 4,000 journal articles since 1955 (according to the Science Citation Index Expanded ...

Michael I. Mishchenko; Larry D. Travis

2008-12-01T23:59:59.000Z

405

Mechanical and electromagnetic transverse load effects on superconducting niobium-tin performance  

E-Print Network (OSTI)

Cable-in-Conduit Conductor is the typical geometry for the conductor employed in superconducting magnets for fusion applications. Once energized, the magnets produce an enormous electromagnetic force and very large transverse ...

Chiesa, Luisa

2009-01-01T23:59:59.000Z

406

High bandwidth rotary fast tool servos and a hybrid rotary/linear electromagnetic actuator  

E-Print Network (OSTI)

This thesis describes the development of two high bandwidth short-stroke rotary fast tool servos and the hybrid rotary/linear electromagnetic actuator developed for one of them. Design insights, trade-off methodologies, ...

Montesanti, Richard Clement

2005-01-01T23:59:59.000Z

407

On the spontaneous emission of electromagnetic radiation in the CSL model  

E-Print Network (OSTI)

Spontaneous photon emission in the Continuous Spontaneous Localization (CSL) model is studied one more time. In the CSL model each particle interacts with a noise field that induces the collapse of its wave function. As a consequence of this interaction, when the particle is electrically charged, it radiates. As discussed in [1], the formula for the emission rate, to first perturbative order, contains two terms: One is proportional to the Fourier component of the noise field at the same frequency as that of the emitted photon and one is proportional to the zero Fourier component of the noise field. As discussed in previous works, this second term seems unphysical. In [1], it was shown that the unphysical term disappears when the noises is confined to a bounded region and the final particle's state is a wave packet. Here we investigate the origin of the unphysical term and why it vanishes according to the previous prescription. For this purpose, the electrodynamic part of the equation of motion is solved exactly while the part due to the noise is treated perturbatively. We show that the unphysical term is connected to exponentially decaying function of time which dies out in the large time limit, however, approximates to 1 in the first perturbative order in the electromagnetic field.

S. Donadi; A. Bassi; D. -A. Deckert

2013-07-03T23:59:59.000Z

408

Feasibility of a MHD generator as a transmitter for electromagnetic sounding of the earth. [Mathematical models  

DOE Green Energy (OSTI)

Development of a high-intensity source for use in time-domain electromagnetic (TDEM) soundings would permit investigation of geothermal systems to much greater depth than is now possible with controlled-source methods. The development of such a source is critically dependent upon a powerful, mobile generator. Magnetohydrodynamic pulse generators satisfy the weight and power requirements for such a generator. However, existing MHD generators which are used in geophysical applications are solid fueled, and therefore, very expensive to operate. Moreover, the pulse length from such a generator is limited to about 10 seconds, which may be too short to permit the maximum advantage to be gained from the available power. The shortcomings of the MHD generator will be remedied in a liquid-fueled generator now under development for the U.S. Air Force. A field program designed to compare available conventional and MHD generators would provide the necessary information for final generator selection, as well as an abundance of information on the nature of geothermal systems at depth. Operation and cost studies on MHD generators are given, and model calculations for TDEM soundings of geothermal hot-dry-rock systems are presented.

Fleming, D.B.

1976-08-10T23:59:59.000Z

409

Guidelines for Electromagnetic Interference Testing of Power Plant Equipment: Revision 3 to TR-102323  

Science Conference Proceedings (OSTI)

To continue meeting safety and reliability requirements while controlling costs, operators of nuclear power plants must be able to replace and upgrade equipment in a cost-effective manner. One issue that has been problematic for new plant equipment and especially for digital instrumentation and control (I&C) systems in recent years is electromagnetic compatibility (EMC). The EMC issue usually involves testing to show that critical equipment will not be adversely affected by electromagnetic interference (...

2004-11-30T23:59:59.000Z

410

Turbine-Generator Topics for Power Plant Engineers: Fundamentals of Electromagnetic Signature Analysis  

Science Conference Proceedings (OSTI)

Electromagnetic signature analysis (EMSA) is the process used to evaluate the electromagnetic interference (EMI) generated by abnormalities in almost any energized power plant equipmentfrom cable connections to broken rotor bars in a motor to the isolated phase bus and generator step-up transformer. EMSA will detect any defect that involves EMI, noise, arcing, corona, partial discharge, gap discharge, sparking or microsparking, or any combination of these.With EMSA, every signal ...

2013-02-15T23:59:59.000Z

411

Review of High Frequency Conducted Susceptibility Limits for Electromagnetic Compatibility Testing  

Science Conference Proceedings (OSTI)

To continue meeting safety and reliability requirements while controlling costs, operators of nuclear power plants must be able to replace and upgrade equipment in a cost-effective manner. One issue that has been problematic for new plant equipment and especially for digital instrumentation and control (I&C) systems in recent years is electromagnetic compatibility (EMC). The EMC issue usually involves testing to show that critical equipment will not be adversely affected by electromagnetic interference (...

2007-12-14T23:59:59.000Z

412

Technical Guidance for Achieving Higher Levels of Electromagnetic Compatibility for Advanced Nuclear Power Plants  

Science Conference Proceedings (OSTI)

This report presents guidance for enhancing electromagnetic compatibility (EMC) for advanced nuclear power plants (NPPs). Included is a summary of EMC challenges facing these plants and the threats that utilities, equipment designers, and plant designers must be aware of. The following requested areas are covered: 1) programmatically addressing EMC through the development of an EMC protection system, 2) minimizing the use of exclusion zones through the demonstration of electromagnetic energy (EM) calcula...

2010-12-22T23:59:59.000Z

413

Wavelet-like bases for thin-wire integral equations in electromagnetics  

Science Conference Proceedings (OSTI)

In this paper, wavelets are used in solving, by the method of moments, a modified version of the thin-wire electric field integral equation, in frequency domain. The time domain electromagnetic quantities, are obtained by using the inverse discrete fast ... Keywords: 02.30.Rz, 02.60.Cb, 02.70.-c, 41.20.-q, 41.20.Jb, M-band wavelet transform, Method of moments, Preconditioning, Thin-wire integral equations in electromagnetics

E. Francomano; A. Tortorici; E. Toscano; G. Ala; F. Viola

2005-03-01T23:59:59.000Z

414

Electromagnetic effects of neutrinos in an electron gas  

E-Print Network (OSTI)

We study the electromagnetic properties of a system that consists of an electron background and a neutrino gas that may be moving or at rest, as a whole, relative to the background. The photon self-energy for this system is characterized by the usual transverse and longitudinal polarization functions, and two additional ones which are the focus of our calculations, that give rise to birefringence and anisotropic effects in the photon dispersion relations. Expressions for them are obtained, which depend on the neutrino number densities and involve momentum integrals over the electron distribution functions, and are valid for any value of the photon momentum and general conditions of the electron gas. Those expressions are evaluated explicitly for several special cases and approximations which are generally useful in astrophysical and cosmological settings. Besides studying the photon dispersion relations, we consider the macroscopic electrodynamic equations for this system, which involve the standard dielectric and permeability constants plus two additional ones related to the photon self-energy functions. As an illustration, the equations are used to discuss the evolution of a magnetic field perturbation in such a medium. This particular phenomena has also been considered in a recent work by Semikoz and Sokoloff as a mechanism for the generation of large-scale magnetic fields in the Early Universe as a consequence of the neutrino-plasma interactions, and allows us to establish contact with a specific application in a well defined context, with a broader scope and from a very different point of view.

Jose' F. Nieves; Sarira Sahu

2005-02-24T23:59:59.000Z

415

Pion-nucleon bremsstrahlung and. delta. electromagnetic moments  

SciTech Connect

A dynamically consistent, gauge invariant model for ..pi..N bremsstrahlung is developed. The ..pi..N dynamics are described through an isobar model fit to the experimental phase shifts. The charge and current operators are constructed in a gauge invariant fashion and include contributions from interaction currents at the ..pi..N..delta.. vertices and from the bare ..delta.. electromagnetic moments. The meaning of such moments for an unstable particle is discussed in detail. From a fit to the ..pi../sup +/p bremsstrahlung data, we extract a dipole moment for the bare ..delta../sup ++/ in the range ..mu../sub ..delta..//sub =//..mu../sub p/approx. =2.5 to 3.5; if the contributions from internal pion and nucleon currents are included, this ratio is somewhat smaller. The ..pi../sup -/p bremsstrahlung data are consistent with a broad range of values for ..mu../sub ..delta..//sub =/, including ..mu../sub ..delta..//sub =/ = 0. The ..delta.. quadrupole moment cannot be extracted meaningfully from the data. We discuss the sensitivity of the extracted values of ..mu../sub ..delta../ to the off-shell extension of the ..pi..N scattering amplitude. The polarization asymmetry is found to be sensitive to ..mu../sub ..delta../ while being less sensitive to off-shell scattering.

Heller, L.; Kumano, S.; Martinez, J.C.; Moniz, E.J.

1987-02-01T23:59:59.000Z

416

Efficient imaging of single-hole electromagnetic data  

SciTech Connect

The extended Born, or localized nonlinear (LN) approximation, of integral equation (IE) solution has been applied to inverting single-hole electromagnetic (EM) data using a cylindrically symmetric model. The extended Born approximation is less accurate than a full solution but much superior to the simple Born approximation. When applied to the cylindrically symmetric model with a vertical magnetic dipole source, however, the accuracy of the extended Born approximation is shown to be greatly improved because the electric field is scalar and continuous everywhere. One of the most important steps in the inversion is the selection of a proper regularization parameter for stability. The extended Born solution provides an efficient means for selecting an optimum regularization parameter, because the Green's functions, the most time consuming part in IE methods, are repeatedly re-usable at each iteration. In addition, the IE formulation readily contains a sensitivity matrix, which can be revised at each iteration at little expense. In this paper we show inversion results using synthetic and field data. The result from field data is compared with that of a 3-D inversion scheme.

Lee, Ki Ha; Kim, Hee Joon; Wilt, Mike

2002-04-01T23:59:59.000Z

417

Evaluation of borehole electromagnetic and seismic detection of fractures  

DOE Green Energy (OSTI)

Experiments were conducted to establish the feasibility of downhole high-frequency techniques for location of fractures in the vicinity of boreholes. An existing flame-cut slot in granite was filled with salt water to simulate a brine-filled fracture. The first method used an electromagnetic wave at 30 to 300 MHz, vhf frequencies. A transmitter consisting of a phased dual-dipole array arranged to provide a directional signal toward the fracture was installed in a borehole opposite the fracture. A receiver was also located in the same borehole. The radar returns from the simulated fracture were detectable in boreholes located at distances of up to 12 meters from the fracture. These results indicate for the first time the feasibility of a downhole vhf radar for use in a single borehole for detection of fractures located away from the borehole. Similar experiments were also conducted using seismic waves at 4.5 to 6 KHz. The transmitter and the receiver in this case were located in separate boreholes. During this experiment, reflections from the slot were obtained only with the transducers oriented for shear wave illumination and detection. These results suggest that a high-frequency shear wave can also be used to detect fractures away from a borehole.

Chang, H.T.; Suhler, S.A.; Owen, T.E.

1984-02-01T23:59:59.000Z

418

Generalized design formulas for low energy electromagnetic quads  

SciTech Connect

This technical note is the result of the quadrupole magnet design efforts that went into the development of proposals for large high-powered linear accelerators such as the Accelerator for Production of Tritium (APT), Accelerator for Base Conversion (of Plutonium) (ABC), and Accelerator for Treatment of (radioactive) Waste (ATW). In all these applications it was necessary to develop designs for numerous (hundreds) of electromagnetic quadrupoles (EMQs). EMQs are required since long-term reliability, radiation damage potential, and large aperture dictate against the use of permanent magnet quadrupoles (PMQs) for these powerful machines. One object of the magnet design effort was to provide a quick, reliable, and easy means of converting raw physics requirements (magnetic impulse, focal length, and boretube aperture) into realistic electrical, cooling, facility interface, and mechanical specifications and configurations--in other words, to easily convert physics requirements to a reliable design that could be drawn on paper, shown to vendors, and presented to peer review committees as a well-developed and believable concept. The empirical formulas that were derived have been gathered together in this technical note. They will be useful for other designers interested in an easy way of coming up with a rather complete mechanical as well as electrical and magnetic design for EMQs. Included are lab tests of designs derived from these formulas and comparisons with other real EMQ designs. These demonstrate the good accuracy of the empirical formulas.

Liska, D.J.

1994-06-01T23:59:59.000Z

419

Electromagnetic soundings for geothermal resources in Dixie Valley, Nevada  

DOE Green Energy (OSTI)

An electromagnetic (EM) sounding survey was performed over a region encompassing the Dixie Valley geothermal field to map the subsurface resistivity in the geothermal field and the surrounding area. The EM survey, consisting of 19 frequency-domain depth soundings made with the LBL EM-60 system, was undertaken to explore a narrow region adjacent to the Stillwater Range to a depth of 2 to 3 km. Lithologic and well log resistivity information from well 66-21 show that for EM interpretation the section can be reduced to a three-layer model consisting of moderately resistive alluvial sediments, low resistivity lacustrine sediments, and high resistivity Tertiary volcanics and older rocks. This three layer model was used as a starting point in interpreting EM sounding data. Variations in resistivity and thickness provided structural information and clues to the accumulation of geothermal fluids. The interpreted soundings reveal a 1 to 1.5-km-deep low-resistivity zone spatially associated with the geothermal field. The shallow depth suggests that the zone detected is either fluid leakage or hydrothermal alteration, rather than high-temperature reservoir fluids. The position of the low-resistivity zone also conforms to changes in depth to the high resistivity basal layer, suggesting that faulting is a control on the location of productive intervals. 10 refs., 7 figs.

Wilt, M.J.; Goldstein, N.E.

1985-03-01T23:59:59.000Z

420

Cerenkov radio pulses from electromagnetic showers in the time domain  

Science Conference Proceedings (OSTI)

The electric field of the Cerenkov radio pulse produced by a single charged particle track in a dielectric medium is derived from first principles. An algorithm is developed to obtain the pulse in the time domain for numerical calculations. The algorithm is implemented in a Monte Carlo simulation of electromagnetic showers in dense media (specifically designed for coherent radio emission applications) as might be induced by interactions of ultrahigh energy neutrinos. The coherent Cerenkov radio emission produced by such showers is obtained simultaneously both in the time and frequency domains. A consistency check performed by Fourier transforming the pulse in time and comparing it to the frequency spectrum obtained directly in the simulations yields, as expected, fully consistent results. The reversal of the time structure inside the Cerenkov cone and the signs of the corresponding pulses are addressed in detail. The results, besides testing algorithms used for reference calculations in the frequency domain, shed new light into the properties of the radio pulse in the time domain. The shape of the pulse in the time domain is directly related to the depth development of the excess charge in the shower and its width to the observation angle with respect to the Cerenkov direction. This information can be of great practical importance for interpreting actual data.

Alvarez-Muniz, Jaime; Romero-Wolf, Andres; Zas, Enrique [Depto. de Fisica de Particulas and Instituto Galego de Fisica de Altas Enerxias, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Department of Physics and Astronomy, University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); Depto. de Fisica de Particulas and Instituto Galego de Fisica de Altas Enerxias, Universidad de Santiago de Compostela, 15782 Santiago de Compostela (Spain)

2010-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Instabilities and generation of a quasistationary magnetic field by the interaction of relativistically intense electromagnetic wave with a plasma  

Science Conference Proceedings (OSTI)

It is shown that the interaction of the superstrong laser radiation with an isotropic plasma leads to the generation of low frequency electromagnetic (EM) waves and in particular a quasistationary magnetic field. When the relativistic circularly polarized transverse EM wave propagates along z-axis, it creates a ponderomotive force, which affects the motion of particles along the direction of its propagation. On the other hand, motion of the particles across the direction of propagation is defined by the ponderomotive potential. The dispersion relation for the transverse EM wave using a special distribution function, which has an anisotropic form, is derived. The dispersion relation is subsequently investigated for a number of special cases. In general, it is shown that the growth rate of the EM wave strongly depends upon its intensity.

Gillani, S. S. A.; Shah, H. A. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Tsintsadze, N. L. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Institute of Physics, Tbilisi 380077 (Georgia); Razzaq, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan)

2010-08-15T23:59:59.000Z

422

Photo- and electroproduction of K{sup 0{Lambda}} near threshold and effects of the K{sup 0} electromagnetic form factor  

SciTech Connect

By extending our previous isobar model to the K{sup 0{Lambda}} isospin channel, we investigate the properties of the K{sup 0{Lambda}} photo- and electroproduction at energies near threshold. It is found that the pseudovector coupling yields significantly larger cross sections. Variation of the K{sub 1} coupling constants has significant effect only on the pseudovector model. The electromagnetic form factor of the neutral kaon K{sup 0} is found to have a sizable effect on the longitudinal cross section of the K{sup 0{Lambda}} electroproduction near the threshold.

Mart, T. [Departemen Fisika, FMIPA, Universitas Indonesia, Depok 16424 (Indonesia)

2011-04-15T23:59:59.000Z

423

[Electromagnetic studies of nuclear structure and reactions]. Progress summary  

SciTech Connect

The experimental goals are focused on developing an understanding of strong interactions and the structure of hadronic systems by determination of the electromagnetic response; these goals will be accomplished through coincidence detection of final states. Nuclear modeling objectives are to organize and interpret the data through a consistent description of a broad spectrum of reaction observables; calculations are performed in a nonrelativistic diagrammatic framework as well as a relativistic QHD approach. Work is described according to the following arrangement: direct knockout reactions (completion of {sup 16}O(e,e{prime}p), {sup 12}C(e,e{prime}pp) progress, large acceptance detector physics simulations), giant resonance studies (intermediate-energy experiments with solid-state detectors, the third response function in {sup 12}C(e,e{prime}p{sub 0}) and {sup 16}O(e,e{prime}p{sub 0}), comparison of the {sup 12}C(e, e{prime}p{sub 0}) and {sup 16}O(e,e{prime}p{sub 3}) reactions, quadrupole strength in the {sup 16}O(e,e{prime}{alpha}{sub 0}) reaction, quadrupole strength in the {sup 12}C(e,e{prime}{alpha}) reaction, analysis of the {sup 12}C(e,e{prime}p{sub 1}) and {sup 16}O(e,e{prime}p{sub 3}) angular distributions, analysis of the {sup 40}Ca(e,e{prime}x) reaction at low q, analysis of the higher-q {sup 12}C(e,e{prime}x) data from Bates), models of nuclear structure (experimental work, Hartree-Fock calculations, phonon excitations in spherical nuclei, shell model calculations, variational methods for relativistic fields), and instrumentation development efforts (developments at CEBAF, CLAS contracts, BLAST developments).

Not Available

1992-12-31T23:59:59.000Z

424

Electromagnetic soundings over a geothermal reservoir in Dixie Valley, Nevada  

DOE Green Energy (OSTI)

An electromagnetic (EM) sounding survey was performed over a region encompassing the Dixie Valley geothermal field with the purpose of mapping the subsurface resistivity in the geothermal field and its surroundings. The EM survey consisted of 19 frequency-domain depth soundings made with the EM-60 system using three separate horizontal-loop transmitters, and was designed to explore a narrow region adjacent to the Stillwater Range to a depth of 2 to 3 k. Most sounding curves could be fitted to three-layer resistivity models. The surface layer is moderately conductive (10 to 15 ohm-m), has a maximum thickness of 500 m, and consists mainly of alluvial fan and lake sediments. More conductive zones are associated with hydrothermally altered rocks; a resistivity high may be associated with siliceous hot spring deposits. The conductive second layer (2 to 5 ohm-m) varies in thickness from 400 to 800 m and thickens toward the center of the valley. This layer probably consists of lacustrine sediments saturated with saline waters. Local resistivity lows observed in the second layer may be related to elevated subsurface temperatures. This layer may act as a cap rock for the geothermal system. Resistivities of the third layer are high (50 to 100 ohm-m) except in a narrow 5-km band paralleling the range front. This low-resistivity zone, within volcanic rocks, correlates well in depth and location with reported zones of geothermal fluid production. It also seems to correlate with the western margin of a concealed graben structure previously inferred from other geophysical data.

Wilt, M.J.; Goldstein, N.E.

1983-04-01T23:59:59.000Z

425

Monitoring of thermal enhanced oil recovery processes with electromagnetic methods  

SciTech Connect

Research in applying electromagnetic methods for imaging thermal enhanced oil recovery has progressed significantly during the past eighteen months. Working together with researchers at Lawrence Berkeley Laboratory (LBL) and supported by a group of industrial sponsors we have focused our effort on field system development and doing field surveys connected with EOR operations. Field surveys were recently completed at the Lost Hills No.3 oil field and at UC Richmond Field station. At Lost Hills, crosshole EM data sets were collected before a new phase of steam injection for EOR and again four months after the onset of steaming. The two data sets were nearly identical suggesting that very little steam had been injected into this borehole. This is in accord with the operators records which indicate injectivity problems with this particular well. At Richmond we conducted a salt water injection monitoring experiment where 50,000 gallons of salt water were injected in a shallow aquifer and crosshole EM data were collected using the injection well and several observation wells. We applied the imaging code to some of the collected data and produced an image showing that the salt water slug has propagated 8--10 m from the injector into the aquifer. This result is partially confirmed by prior calculations and well logging data. Applying the EM methods to the problem of oil field characterization essentially means extending the borehole resistivity log into the region between wells. Since the resistivity of a sedimentary environment is often directly dependent on the fluids in the rock the knowledge of the resistivity distribution within an oil field can be invaluable for finding missed or bypassed oil or for mapping the overall structure. With small modification the same methods used for mapping EOR process can be readily applied to determining the insitu resistivity structure.

Wilt, M.

1992-09-01T23:59:59.000Z

426

The Study of Electromagnetic Shielding Employing Woven Continuous Carbon Fiber Composites for 2.5Gb/s Transceiver Modules.  

E-Print Network (OSTI)

??A High electromagnetic shielding, light weight, low cost plastic package is developed by using a woven continuous carbon fiber (WCCF) epoxy composite. Three different weaving (more)

Lee, Chien-hui

2004-01-01T23:59:59.000Z

427

Accident Investigation Handbook  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Improvement (HPI). The recommended techniques apply equally well to DOE Federal-led accident investigations conducted under DOE Order (O) 225.1B, Accident Investigations,...

428

Electromagnetic Imaging of CO2 Sequestration at an Enhanced Oil Recovery Site  

NLE Websites -- All DOE Office Websites (Extended Search)

Electromagnetic Imaging of CO Electromagnetic Imaging of CO 2 Sequestration at an Enhanced Oil Recovery Site Barry Kirkendall (Kirkendall1@llnl.gov ; 925-423-1513) Jeff Roberts (Roberts17@llnl.gov ; 925-422-7108) Lawrence Livermore National Laboratory 7000 East Avenue Livermore, CA 94550 1.1 Introduction Lawrence Livermore National Laboratory (LLNL) is currently involved in a long term study using time-lapse multiple frequency electromagnetic (EM) characterization at a waterflood enhanced oil recovery (EOR) site in California operated by Chevron Heavy Oil Division in Lost Hills, California (Figure 1). The petroleum industry's interest and the successful imaging results from this project suggest that this technique be extended to monitor CO 2 sequestration at an EOR site also operated by Chevron. The impetus for this study is

429

Electromagnetic geophysics: Notes from the past and the road ahead | Open  

Open Energy Info (EERE)

Electromagnetic geophysics: Notes from the past and the road ahead Electromagnetic geophysics: Notes from the past and the road ahead Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Electromagnetic geophysics: Notes from the past and the road ahead Abstract During the last century, electrical geophysics has been transformed from a simple resistivity method to a modern technology that uses complex data-acquisition systems and high-performance computers for enhanced data modeling and interpretation. Not only the methods and equipment have changed but also our ideas about the geoelectrical models used for interpretation have been modified tremendously. This paper describes the evolution of the conceptual and technical foundations of EM methods. Author Michael S. Zhdanov Published Journal

430

Time-Domain Electromagnetics At Long Valley Caldera Area (Sorey, Et Al.,  

Open Energy Info (EERE)

1991) 1991) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Time-Domain Electromagnetics At Long Valley Caldera Area (Sorey, Et Al., 1991) Exploration Activity Details Location Long Valley Caldera Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes In 1986, Unocal Geothermal Division released results from 158 time-domain electromagnetic (TDEM) soundings and, with Chevron Resources, a total of 77 magnetotelluric (MT) stations. Reinterpretations of the Unocal and Chevron data (Park and Torres-Verdin, 1988 ) and the recent public-domain MT studies (e.g. Hermance et al., 1988) outline similar shallow low-resistivity regions. At shallow depths in the caldera References Michael L. Sorey, Gene A. Suemnicht, Neil C. Sturchio, Gregg A.

431

Time-Domain Electromagnetics At Kilauea Southwest Rift And South Flank Area  

Open Energy Info (EERE)

And South Flank Area And South Flank Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Time-Domain Electromagnetics At Kilauea Southwest Rift And South Flank Area (Thomas, 1986) Exploration Activity Details Location Kilauea Southwest Rift And South Flank Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes The assessment effort consisted of a reexamination of existing Schlumberger sounding (Hussong and Cox, 1967; Adams et al., 1970) and time-domain electromagnetic (Klein and Kauahikaua, 1975) data for the rift area (Kauahikaua and Mattice, 1981) The electrical resistivity data acquired on the southwest rift delineated two distinct basement resistivity structures northwest of the rift zone: a high-resistivity basement at approximately 60

432

Time-Domain Electromagnetics At Truckhaven Area (Warpinski, Et Al., 2004) |  

Open Energy Info (EERE)

Time-Domain Electromagnetics At Truckhaven Area Time-Domain Electromagnetics At Truckhaven Area (Warpinski, Et Al., 2004) Exploration Activity Details Location Truckhaven Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness useful DOE-funding Unknown Notes The Truckhaven project, which is located on the west flank of the Salton Trough in southern California, is north and west of several existing geothermal power generation facilities in the trough. An extensive shallow geothermal anomaly is known to exist in this area and this region corresponds to a gravity high, which has been further delineated by the drilling of numerous shallow temperature gradient wells and one deep, abandoned, test well. Layman Energy Associates has performed Phase I exploration tasks to further constrain the anomaly, including a detailed

433

Microsoft Word - Lamellae tungsten tile design thermal and electromagnetic stress analysis_Final.doc  

NLE Websites -- All DOE Office Websites (Extended Search)

Lamellae tungsten tile design transient Lamellae tungsten tile design transient thermal/ electromagnetic stress analysis Thomas Willard*, Rui Vieira, Samuel Pierson MIT Plasma Science and Fusion Center, Cambridge, MA 02139 8 June 2006 Abstract A transient thermal/ electromagnetic stress analysis of the lamellae tungsten tile design has been performed to determine if the design is adequate to meet the maximum design load conditions of 12 MW/ m 2 uniform heat flux for 5 seconds (single pulse, no Diverter Plate temperature ratcheting) , superimposed on the electromagnetic body load due to eddy currents generated by disruptions. The results show that the design is adequate, with the stresses in the tungsten lamellae and the TZM molybdenum hardware less than the ultimate strength of

434

Time-Domain Electromagnetics At Dixie Hot Springs Area (Combs 2006) | Open  

Open Energy Info (EERE)

Hot Springs Area (Combs 2006) Hot Springs Area (Combs 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Time-Domain Electromagnetics At Dixie Hot Springs Area (Combs 2006) Exploration Activity Details Location Dixie Hot Springs Area Exploration Technique Time-Domain Electromagnetics Activity Date Usefulness not indicated DOE-funding Unknown Notes "MT, EM sounding, SP?; SP data and reservoir model may be proprietary" References Jim Combs (1 January 2006) Historical Exploration And Drilling Data From Geothermal Prospects And Power Generation Projects In The Western United States Retrieved from "http://en.openei.org/w/index.php?title=Time-Domain_Electromagnetics_At_Dixie_Hot_Springs_Area_(Combs_2006)&oldid=388997" Category: Exploration

435

Electromagnetic energy within a magnetic infinite cylinder and scattering properties for oblique incidence  

E-Print Network (OSTI)

In this work we analytically calculate the time-averaged electromagnetic energy stored inside a nondispersive magnetic isotropic cylinder which is obliquely irradiated by an electromagnetic plane wave. An expression for the optical-absorption efficiency in terms of the magnetic internal coefficients is also obtained. In the low absorption limit, we derive a relation between the normalized internal energy and the optical-absorption efficiency which is not affected by the magnetism and the incidence angle. This mentioned relation, indeed, seems to be independent on the shape of the scatterer. This universal aspect of the internal energy is connected to the transport velocity and consequently to the diffusion coefficient in the multiple scattering regime. Magnetism favors high internal energy for low size parameter cylinders, which leads to a low diffusion coefficient for electromagnetic propagation in 2D random media.

Tiago Jose Arruda; Alexandre Souto Martinez

2010-10-14T23:59:59.000Z

436

Strong and Electromagnetic J/psi and psi(2S) Decays into Pion and Kaon Pairs  

E-Print Network (OSTI)

A combined analysis of the electromagnetic pion and kaon form factors in the neighborhood of J/psi and psi(2S) and of the strong decay amplitude of these resonances into kaons is presented. In the presence of a large relative phase between strong and electromagnetic resonance amplitudes the branching ratio, as measured in electron-positron annihilation, receives an additional contribution from the interference between resonance and continuum amplitude neglected in earlier papers. Our study is model independent and does not rely on the SU(3) symmetry assumptions used in earlier papers. We note that the large relative phase between strong and electromagnetic amplitudes observed in earlier analyses is model dependent and relies critically on the specific assumptions on SU(3) symmetry and breaking.

Czyz, Henryk

2009-01-01T23:59:59.000Z

437

Electron interference in mesoscopic devices in the presence of nonclassical electromagnetic fields  

E-Print Network (OSTI)

The interaction of mesoscopic interference devices with nonclassical electromagnetic fields is studied. The external quantum fields induce a phase factor on the electric charges. This phase factor, which is a generalization of the standard Aharonov-Bohm phase factor, is in the case of nonclassical electromagnetic fields a quantum mechanical operator. Its expectation value depends on the density matrix describing the nonclassical photons and determines the interference. Several examples are discussed, which show that the quantum noise of the nonclassical photons destroys slightly the electron interference fringes. An interesting application arises in the context of distant electron interference devices, irradiated with entangled photons. In this case the interfering electrons in the two devices become entangled. The same ideas are applied in the context of SQUID rings irradiated with nonclassical electromagnetic fields. It is shown that the statistics of the Cooper pairs tunneling through the Josephson junction depend on the statistics of the photons.

D. I. Tsomokos; C. C. Chong; A. Vourdas

2005-02-18T23:59:59.000Z

438

Strong and Electromagnetic J/psi and psi(2S) Decays into Pion and Kaon Pairs  

E-Print Network (OSTI)

A combined analysis of the electromagnetic pion and kaon form factors in the neighborhood of J/psi and psi(2S) and of the strong decay amplitude of these resonances into kaons is presented. In the presence of a large relative phase between strong and electromagnetic resonance amplitudes the branching ratio, as measured in electron-positron annihilation, receives an additional contribution from the interference between resonance and continuum amplitude neglected in earlier papers. Our study is model independent and does not rely on the SU(3) symmetry assumptions used in earlier papers. We note that the large relative phase between strong and electromagnetic amplitudes observed in earlier analyses is model dependent and relies critically on the specific assumptions on SU(3) symmetry and breaking.

Henryk Czyz; Johann H. Kuhn

2009-04-03T23:59:59.000Z

439

Exact microscopic theory of electromagnetic heat transfer between a dielectric sphere and plate  

E-Print Network (OSTI)

Near-field electromagnetic heat transfer holds great potential for the advancement of nanotechnology. Whereas far-field electromagnetic heat transfer is constrained by Planck's blackbody limit, the increased density of states in the near-field enhances heat transfer rates by orders of magnitude relative to the conventional limit. Such enhancement opens new possibilities in numerous applications, including thermal-photo-voltaics, nano-patterning, and imaging. The advancement in this area, however, has been hampered by the lack of rigorous theoretical treatment, especially for geometries that are of direct experimental relevance. Here we introduce an efficient computational strategy, and present the first rigorous calculation of electromagnetic heat transfer in a sphere-plate geometry, the only geometry where transfer rate beyond blackbody limit has been quantitatively probed at room temperature. Our approach results in a definitive picture unifying various approximations previously used to treat this problem, and provides new physical insights for designing experiments aiming to explore enhanced thermal transfer.

Clayton Otey; Shanhui Fan

2011-03-14T23:59:59.000Z

440

The dispersion relation and excitation of transverse magnetic mode electromagnetic waves in rippled-wall waveguide with a plasma rod and an annular dielectric  

Science Conference Proceedings (OSTI)

By using the linear field theory, the dispersion relation of electromagnetic waves in a rippled-wall waveguide with a plasma rod and an annular dielectric is obtained. In addition, by injecting a finite thick annular intense relativistic electron beam in this waveguide, the excitation of these waves is investigated. Furthermore, the effects of the radius of the plasma rod, the radius of the dielectric, the corrugation amplitude, and period on the frequency spectrum are investigated. Besides, the time growth rate of excitation of these waves by an annular relativistic electron beam is studied. Finally, to demonstrate the advantages of this rippled-wall waveguide, the dispersion relation and the growth rate of three simplified cases are investigated.

Nejati, M. [Physics Department, Shahid Beheshti University, G. C. Evin, Tehran (Iran, Islamic Republic of); Shokri, B. [Physics Department and Laser-Plasma Research Institute, Shahid Beheshti University, G. C. Evin, Tehran (Iran, Islamic Republic of)

2012-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Program on Technology Innovation: Frequently Asked Questions (FAQ) on Radio-Frequency Electromagnetic Fields  

Science Conference Proceedings (OSTI)

The number of sources of radio-frequency (RF) electromagnetic fields in our midst has increased dramatically in the past three decades.From cordless phones, to cellular phones and their base stations, to pagers and walkie-talkies, to WiFi in public venues, such as coffee shops and airports, and to smart meters and other wireless components of the smart grid.Of course, since the advent of broadcast radio and TV during the 20th century, radio-frequency electromagnetic fields have been an ...

2012-11-05T23:59:59.000Z

442

Magnetic field effect on stimulated Raman scattering of electromagnetic waves from nanoparticle lattice  

Science Conference Proceedings (OSTI)

The influence of a static magnetic field on the Raman scattering of a millimeter pump wave propagating through periodic nanoparticles is studied. Formulas for the growth rate of the scattered electromagnetic wave and the electrostatic wave are derived and analyzed. It is found that the growth rate for the backscattering case is larger than that of forward scattering and the growth rate is increased by the static magnetic field. A resonance in the dispersion relation of the electromagnetic wave is found as a combination of the cyclotron and plasma frequency. However, no instability was found for this lower branch of the dispersion curve.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2011-02-15T23:59:59.000Z

443

Guidelines for Electromagnetic Interference Testing of Power Plant Equipment: Revision 3 to TR-102323  

SciTech Connect

To continue meeting safety and reliability requirements while controlling costs, operators of nuclear power plants must be able to replace and upgrade equipment in a cost-effective manner. One issue that has been problematic for new plant equipment and especially for digital instrumentation and control (I&C) systems in recent years is electromagnetic compatibility (EMC). The EMC issue usually involves testing to show that critical equipment will not be adversely affected by electromagnetic interference (EMI) in the plant environment. This guide will help nuclear plant engineers address EMC issues and qualification testing in a consistent, comprehensive manner.

J. Cunningham and J. Shank

2004-11-01T23:59:59.000Z

444

The influence of an electromagnetic field on the wave-current interaction  

E-Print Network (OSTI)

We study the propagation of surface waves on a current in the presence of an electromagnetic field. A horizontal (vertical) field strengthens (weakens) the counter-current which blocks the waves. We compute the phase space diagrams (blocking velocities versus period of the waves) with and without surface tension. Three new dimensionless numbers are introduced to compare the relative strengths of gravity, surface tension and field effects. This work shows the importance of an electromagnetic field in order to design wave-breakers or in microfluidics applications.

Germain Rousseaux; Philippe Massa

2010-10-11T23:59:59.000Z

445

Poynting-vector based method for determining the bearing and location of electromagnetic sources  

DOE Patents (OSTI)

A method and apparatus is utilized to determine the bearing and/or location of sources, such as, alternating current (A.C.) generators and loads, power lines, transformers and/or radio-frequency (RF) transmitters, emitting electromagnetic-wave energy for which a Poynting-Vector can be defined. When both a source and field sensors (electric and magnetic) are static, a bearing to the electromagnetic source can be obtained. If a single set of electric (E) and magnetic (B) sensors are in motion, multiple measurements permit location of the source. The method can be extended to networks of sensors allowing determination of the location of both stationary and moving sources.

Simons, David J. (Modesto, CA); Carrigan, Charles R. (Tracy, CA); Harben, Philip E. (Livermore, CA); Kirkendall, Barry A. (Golden, CO); Schultz, Craig A. (Danville, CA)

2008-10-21T23:59:59.000Z

446

Calibration case study of natural source electromagnetic array data recorded over a well in Oregon  

Science Conference Proceedings (OSTI)

Natural field electromagnetic acquired conventionally, at a number of sparsely spaced single sites, can suffer from spatial aliasing and significant distortive shallow effects which severely limit its geophysical applications. A new mode of data acquisition which measures the electric field continuously along a profile has been developed by F.X. Boxtick. These data can be processed to remove shallow effects while maintaining the deep penetration characteristics of the natural electromagnetic (EM) fields. Processing and modeling techniques for such data are discussed and demonstrated on both synthetic and field data. Very good agreement with actual borehole data is demonstrated.

Shoemaker, C.L.; Shoham, Y.; Hockey, R.

1989-02-01T23:59:59.000Z

447

FELIX: an experimental facility to study electromagnetic effects for first wall, blanket, and shield systems  

Science Conference Proceedings (OSTI)

As part of the DOE First Wall/Blanket/Shield (FW/B/S) Engineering Test Program, Argonne National Laboratory (ANL) is carrying out an experimental program to study electromagnetic effects. Electromagnetic effect in a FW/B/S system include time delay of equilibrium field penetration to the plasma, forces and torques, eddy current heating, and electrical arcing. Such effects can arise in a fusion reactor from plasma disruption and normal and abnormal charge and discharge of the magnets. The facility will consist primarily of a solenoid magnet, a surrounding pulsed dipole magnet, and associated power supplies and support structure.

Praeg, W.F.; Turner, L.R.; Biggs, J.; Bywater, J.; Fuja, R.; Knott, M.; Lari, R.J.; McGhee, D.G.; Wehrle, R.B.

1981-01-01T23:59:59.000Z

448

Investigations | Department of Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigations Investigations Investigations Investigations The Office of Investigations performs investigations into allegations of fraud, waste, and abuse in programs and operations of the Department, NNSA and FERC. Priority is given to investigations of suspected violations of criminal and civil statutes, as well as serious administrative misconduct. Particular focus is placed on the prevention and detection of contract and grant fraud; environmental, health and safety violations; computer crimes; and issues that reflect on the integrity and credibility of Department officials. Suspected criminal and civil violations are reported promptly to the Department of Justice for prosecutive consideration. Potential outcomes from such referrals include declination or acceptance for further action,

449

Simulation Study on the Characteristics of Carbon-Fiber-Reinforced Plastics in Electromagnetic Tomography Nondestructive Evaluation Systems  

Science Conference Proceedings (OSTI)

Simulations of carbon-fiber-reinforced plastics (CFRP) using the finite element method in electromagnetic tomography nondestructive evaluation systems are presented in this paper. Ansoft Maxwell 3D models describing the interaction of the sensors with ... Keywords: Carbon-fiber-reinforced plastics (CFRP), finite element, electromagnetic tomography (EMT), nondestructive evaluation (NDE), sensitivity matrix

Ze Liu; Yu Xu; Xiaofei Zhang; Yali Pei; Yiping Cheng; Wuliang Yin

2010-03-01T23:59:59.000Z

450

Waveform Distortion on a 7-Channel Heart Monitor Produced by a Worn Cable Connector & 60-Hertz Electromagnetic Fields  

Science Conference Proceedings (OSTI)

This case study describes an equipment-to-electromagnetic environment incompatibility that occurred in a training laboratory that is part of a large teaching hospital. Specifically, it discusses the causes of low-frequency electromagnetic fields that led to the malfunction of a 7-channel heart monitor used in cardiovascular surgical training to monitor, record, and display small electrical impulses associated with the heart.

2003-12-31T23:59:59.000Z

451

Electromagnetic Shielding Performance of Nickel-coated Carbon ...  

Science Conference Proceedings (OSTI)

Microstructural Investigation of Nano-Calcium Phosphates Doped with Fluoride Ions .... Surfactant Structureproperty Relationship: Effect of Polypropylene Glycol ... The Effect of Monobutyl Ether Ethylene Glycol on the Conductivity and the...

452

The effects of cultural noise on controlled source electromagnetic resonses of subsurface fractures in resistive terrain  

E-Print Network (OSTI)

Controlled source electromagnetic (CSEM) geophysics has been used with a fair amount of success in near surface hydrogeological studies. Recently, these investigations have been conducted frequently in human impacted field sites containing cultural conductors such as metal fences and buried pipes. Cultural noise adds an element of complexity to the geological interpretation of this type of data. This research investigates the influence of mutual induction between two buried targets in a CSEM experiment. In particular, it looks at the mutual coupling between a buried cultural conductor and a geological heterogeneity. We attempt to isolate the Hz field induced by tertiary currents in targets caused by mutual coupling. This is achieved with a Texas A&M 3D CSEM finite element code, which calculates the secondary Hz fields emanating from a target buried in a halfspace. Buried geological targets and cultural conductors are modeled as volumetric slabs embedded in a halfspace. A series of models have been simulated to study the effect of varying parameters such as target conductivity, transmitter location and shape of a target on the mutual inductance. In each case, the secondary Hz field is calculated for a model with two slabs, and two models with individual slabs. The mutual coupling is calculated by removing the secondary fields from the individual slab models from the response of a two slab model. The calculations of mutual inductance from a variety of such models suggests a complicated interaction of EM fields between the two targets. However, we can explain most of these complexities by adapting a simple approach to Maxwells equations. Although the tertiary Hz field is complicated, it may be useful in the characterization and delineation of electrical heterogeneities in the subsurface, which can then be related to geological features such as fractures or joints. It is seen that the most important factor affecting the mutual coupling is the host conductivity. The results have also shown that mutual coupling is very sensitive to transmitter (TX) location, especially when the TX is positioned near one of the targets.

Fernandes, Roland Anthony Savio

2008-05-01T23:59:59.000Z

453

FAQs - NIST WTC Investigation  

Science Conference Proceedings (OSTI)

... The agency received $16 million for the investigation in September 2002 from the federal government's fiscal year 2002 supplemental appropriation ...

2011-09-20T23:59:59.000Z

454

Would be the photon a composed particle? quantization of field fluxes in electromagnetic radiation  

E-Print Network (OSTI)

[En] Here it is made a comparative analysis between the classical and the quantum expressions for the energy of electromagnetic radiation (ER). The comparison points to the possibility of the quantization of the magnetic and the electric field fluxes in the ER.

Celso de Araujo Duarte

2013-05-15T23:59:59.000Z

455

FULL ELECTROMAGNETIC FEL SIMULATION VIA THE LORENTZ-BOOSTED FRAME TRANSFORMATION  

SciTech Connect

Numerical electromagnetic simulation of some systems containing charged particles with highly relativistic directed motion can by speeded up by orders of magnitude by choice of the proper Lorentz-boosted frame. A particularly good application for calculation in a boosted frame isthat of short wavelength free-electron lasers (FELs) where a high energy electron beam with small fractional energy spread interacts with a static magnetic undulator. In the optimal boost frame (i.e., the ponderomotive rest frame), the red-shifted FEL radiation and blue-shifted undulator field have identical wavelengths and the number of required longitudinal grid cells and time-steps for fully electromagnetic simulation (relative to the laboratory frame) decrease by factors of gamma^2 each. In theory, boosted frame EM codes permit direct study of FEL problems for which the eikonal approximation for propagation of the radiation field and wiggler-period-averaging for the particle-field interaction may be suspect. We have adapted the WARP code to apply this method to several electromagnetic FEL problems including spontaneous emission, strong exponential gain in a seeded, single pass amplifier configuration, and emission from e-beams in undulators with multiple harmonic components. WARP has a standard relativistic macroparticle mover and a fully 3-D electromagnetic field solver. We discuss our boosted frame results and compare with those obtained using the ?standard? eikonal FEL simulation approach.

Fawley, William; Vay, Jean-Luc

2010-08-16T23:59:59.000Z

456

Guidelines for Electromagnetic Interference Testing of Power Plant Equipment: Revision 2 to TR-102323  

Science Conference Proceedings (OSTI)

This revision to the original guide, which received U.S. Nuclear Regulatory Commission (NRC) approval in a Safety Evaluation Report (SER) in April 1996, reduces excessive conservatism in plant equipment emission and susceptibility testing limits. It identifies emissions sources in nuclear power plants, recommends susceptibility and emissions standards, and details design and layout practices for minimizing susceptibility to electromagnetic interference (EMI).

2000-12-01T23:59:59.000Z

457

A lattice Boltzmann model for electromagnetic waves propagating in a one-dimensional dispersive medium  

Science Conference Proceedings (OSTI)

A first-order extended lattice Boltzmann (LB) model with special forcing terms for one-dimensional Maxwell equations exerting on a dispersive medium, described either by the Debye or Drude model, is proposed in this study. The time dependent dispersive ... Keywords: Debye model, Dispersive medium, Drude model, Electromagnetic waves, Lattice Boltzmann method, Lorentz model

Poting Chen; Chen-Hao Wang; Jeng-Rong Ho

2013-03-01T23:59:59.000Z

458

Motion control for a vertical rigid rotor rotating in electromagnetic bearings  

Science Conference Proceedings (OSTI)

The problems of control of a motion of a rigid rotor in electromagnetic bearings are considered. The main ides of synthesis of the control laws is the approach based on feedback linearization of the original nonlinear mathematical model of the system. ...

D. V. Balandin; M. M. Kogan

2011-10-01T23:59:59.000Z

459

Using Helicopter Electromagnetic Surveys to Identify Potential Hazards at Mine Waste Impoundments  

Science Conference Proceedings (OSTI)

In July 2003, helicopter electromagnetic surveys were conducted at 14 coal waste impoundments in southern West Virginia. The purpose of the surveys was to detect conditions that could lead to impoundment failure either by structural failure of the embankment or by the flooding of adjacent or underlying mine works. Specifically, the surveys attempted to: 1) identify saturated zones within the mine waste, 2) delineate filtrate flow paths through the embankment or into adjacent strata and receiving streams, and 3) identify flooded mine workings underlying or adjacent to the waste impoundment. Data from the helicopter surveys were processed to generate conductivity/depth images. Conductivity/depth images were then spatially linked to georeferenced air photos or topographic maps for interpretation. Conductivity/depth images were found to provide a snapshot of the hydrologic conditions that exist within the impoundment. This information can be used to predict potential areas of failure within the embankment because of its ability to image the phreatic zone. Also, the electromagnetic survey can identify areas of unconsolidated slurry in the decant basin and beneath the embankment. Although shallow, flooded mineworks beneath the impoundment were identified by this survey, it cannot be assumed that electromagnetic surveys can detect all underlying mines. A preliminary evaluation of the data implies that helicopter electromagnetic surveys can provide a better understanding of the phreatic zone than the piezometer arrays that are typically used.

Hammack, R.W.

2008-01-01T23:59:59.000Z

460

Harmonic filters influences regarding the power quality on high frequency electrothermal installation with electromagnetic induction  

Science Conference Proceedings (OSTI)

This paper presents a study regarding the functioning of a melting/hardening electrothermal installation with electromagnetic induction from the point of view of generated harmonics in the power distribution. The authors made simulations in scope of ... Keywords: electrothermal installation, harmonic, passive filters, static converter

Raluca Rob; Ioan Sora; Caius Panoiu; Manuela Panoiu

2010-01-01T23:59:59.000Z

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461

Developing a time-domain finite-element method for modeling of electromagnetic cylindrical cloaks  

Science Conference Proceedings (OSTI)

In this paper we propose a time-domain finite element method for modeling of electromagnetic cloaks. The permittivity and permeability of the cloak model are described by the Drude dispersion model. The model to be solved is quite challenging in that ... Keywords: Finite element method, Invisibility cloak, Maxwell's equations

Jichun Li; Yunqing Huang; Wei Yang

2012-04-01T23:59:59.000Z

462

Multipole radiation in a collisonless gas coupled to electromagnetism or scalar gravitation  

E-Print Network (OSTI)

We consider the relativistic Vlasov-Maxwell and Vlasov-Nordstr\\"om systems which describe large particle ensembles interacting by either electromagnetic fields or a relativistic scalar gravity model. For both systems we derive a radiation formula analogous to the Einstein quadrupole formula in general relativity.

Sebastian Bauer; Markus Kunze; Gerhard Rein; Alan D. Rendall

2005-08-29T23:59:59.000Z

463

arXiv:astro-ph/0703364v227Aug2007 Electromagnetic dark energy  

E-Print Network (OSTI)

arXiv:astro-ph/0703364v227Aug2007 Electromagnetic dark energy Christian Beck School of MathematicalGill University, Montreal, Quebec, Canada (Dated: August 28, 2007) We introduce a new model for dark energy equations, or more generally with the existence of dark energy. The dark energy density consistent

Low, Robert

464

Problem of the decay instability of electromagnetic waves in a magnetoactive plasma  

SciTech Connect

The processes of decay of transverse electromagnetic waves propagating across a constant magnetic field are considered. The possibility of using these decays for tuning the frequency of the stimulated radiation in the magnetoactive plasma of semiconductors, as well as for the diagnostics of the magnetic fields that spontaneously develop in a laser plasma is discussed.

Roslyakov, V.A.; Starostin, A.N.

1977-11-01T23:59:59.000Z

465

Free Form of the Foldy-Wouthuysen Transformation in External Electromagnetic Fields  

E-Print Network (OSTI)

We derive the exact Foldy-Wouthuysen transformation for Dirac fermions in a time independent external electromagnetic field in the basis of the Ritus eigenfunctions, namely the eigenfunctions of the operator $(\\gamma \\cdot \\Pi)^2$, with $\\Pi^\\mu = p^\\mu - e A^\\mu$. In this basis, the transformation acquires a free form involving the dynamical quantum numbers induced by the field.

Gabriela Murguia; Alfredo Raya

2010-08-29T23:59:59.000Z

466

Electromagnetic field of the large power cables and impact on the human health  

Science Conference Proceedings (OSTI)

In this work we survey our research on domain decomposition and related algorithms for large power electric cables and the impact on the human health. The equations that describe the behaviour of the fields in electromagnetic devices are coupled because ... Keywords: bioheat equation, coupled fields, electrical cables, finite element method

Daniela Crstea

2012-01-01T23:59:59.000Z

467

Electromagnetic field of the large power cables and interaction with the human body  

Science Conference Proceedings (OSTI)

In this work we survey our research on domain decomposition and related algorithms for large power electric cables and the impact on the human health. The equations that describe the behaviour of the fields in electromagnetic devices are coupled because ... Keywords: bioheat equation, coupled fields, electrical cables, finite element method

Daniela Crstea

2010-07-01T23:59:59.000Z

468

Coupled Deconvolution for Frequency Extrapolation of Electromagnetic Solutions with Matrix Pencil Method  

E-Print Network (OSTI)

of electromagnetic solutions," 2005 IEEE AP-S International Symposium, Washington, DC, July 2005. [2] Alan V extrapolation results to achieve a lower error level. We first define two window functions in the solution in the interval (fL, fmax). Fig. 1 shows two Chebyshev windows that are constructed in this manner. Forward MPM

Gürel, Levent

469

Determination of High-Frequency Current Distribution Using EMTP-Based Transmission Line Models with Resulting Radiated Electromagnetic Fields  

SciTech Connect

Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.

Mork, B; Nelson, R; Kirkendall, B; Stenvig, N

2009-11-30T23:59:59.000Z

470

Textile - Compressor Trip Investigation  

Science Conference Proceedings (OSTI)

This power quality (PQ) case study presents the investigation of an 800 HP, 4160 volt compressor that has been tripping off at a textile manufacturing facility.

2003-12-31T23:59:59.000Z

471

Electromagnetic Detection and Real-Time DMLC Adaptation to Target Rotation During Radiotherapy  

SciTech Connect

Purpose: Intrafraction rotation of more than 45 Degree-Sign and 25 Degree-Sign has been observed for lung and prostate tumors, respectively. Such rotation is not routinely adapted to during current radiotherapy, which may compromise tumor dose coverage. The aim of the study was to investigate the geometric and dosimetric performance of an electromagnetically guided real-time dynamic multileaf collimator (DMLC) tracking system to adapt to intrafractional tumor rotation. Materials/Methods: Target rotation was provided by changing the treatment couch angle. The target rotation was measured by a research Calypso system integrated with a real-time DMLC tracking system employed on a Varian linac. The geometric beam-target rotational alignment difference was measured using electronic portal images. The dosimetric accuracy was quantified using a two-dimensional ion chamber array. For each beam, the following five delivery modes were tested: 1) nonrotated target (reference); 2) fixed rotated target with tracking; 3) fixed rotated target without tracking; 4) actively rotating target with tracking; and 5) actively rotating target without tracking. Dosimetric performance of the latter four modes was measured and compared to the reference dose distribution using a 3 mm/3% {gamma}-test. Results: Geometrically, the beam-target rotational alignment difference was 0.3 Degree-Sign {+-} 0.6 Degree-Sign for fixed rotation and 0.3 Degree-Sign {+-} 1.3 Degree-Sign for active rotation. Dosimetrically, the average failure rate for the {gamma}-test for a fixed rotated target was 11% with tracking and 36% without tracking. The average failure rate for an actively rotating target was 9% with tracking and 35% without tracking. Conclusions: For the first time, real-time target rotation has been accurately detected and adapted to during radiation delivery via DMLC tracking. The beam-target rotational alignment difference was mostly within 1 Degree-Sign . Dose distributions to fixed and actively rotating targets with DMLC tracking were significantly superior to those without tracking.

Wu Junqing [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); School of Health Sciences, Purdue University, West Lafayette, IN (United States); Ruan, Dan [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Cho, Byungchul [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Asan Medical Center, Seoul (Korea, Republic of); Sawant, Amit [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Petersen, Jay; Newell, Laurence J. [Calypso Medical Technologies, Seattle, WA (United States); Cattell, Herbert [Varian Medical Systems, Palo Alto, CA (United States); Keall, Paul J., E-mail: radphyslab@sydney.edu.au [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Sydney (Australia)

2012-03-01T23:59:59.000Z

472

Signals of electric muscle activity as markers of the effect of low-intensity electromagnetic emissions (Method and Experimental Results)  

Science Conference Proceedings (OSTI)

We present the method and describe results of an experimental study of electromyographic (EMG) changes under the influence of low-intensity electromagnetic transmitters (EMT). To study the EMT effect on humans, we propose a method based on special processing ...

O. E. Khutorskaya

2010-12-01T23:59:59.000Z

473

Electromagnetically superconducting phase of QCD vacuum induced by strong magnetic field  

SciTech Connect

In this talk we discuss our recent suggestion that the QCD vacuum in a sufficiently strong magnetic field (stronger than 10{sup 16} Tesla) may undergo a spontaneous transition to an electromagnetically superconducting state. The possible superconducting state is anisotropic (the vacuum exhibits superconductivity only along the axis of the uniform magnetic field) and inhomogeneous (in the transverse directions the vacuum structure shares similarity with the Abrikosov lattice of an ordinary type-II superconductor). The electromagnetic superconductivity of the QCD vacuum is suggested to occur due to emergence of specific quark-antiquark condensates which carry quantum numbers of electrically charged rho mesons. A Lorentz-covariant generalization of the London transport equations for the magnetic-field-induced superconductivity is given.

Chernodub, M. N. [CNRS, Laboratoire de Mathematiques et Physique Theorique, Universite Francois-Rabelais Tours, Federation Denis Poisson, Parc de Grandmont, 37200 Tours (France); Department of Physics and Astronomy, University of Gent, Krijgslaan 281, S9, B-9000 Gent (Belgium)

2011-05-23T23:59:59.000Z

474

Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances  

Science Conference Proceedings (OSTI)

The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.

Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A. [Electromagnetic cluster, Universiti Teknologi Petronas, 31750 Tronoh, Perak (Malaysia)

2012-09-26T23:59:59.000Z

475

Electromagnetic Decay of the $\\Sigma^{0}(1385)$ to $\\Lambda\\gamma$  

SciTech Connect

The electromagnetic decay $\\Sigma^0(1385) \\to \\Lambda \\gamma$ was studied using the CLAS detector at the Thomas Jefferson National Accelerator Facility. A real photon beam with a maximum energy of 3.8 GeV was incident on a proton target, producing an exclusive final state of $K^+\\Sigma^{*0}$. We report the decay widths ratio $\\Sigma^0(1385) \\to \\Lambda\\gamma$/ $\\Sigma^0(1385) \\to \\Lambda\\pi^0$ = $1.42 \\pm 0.12(\\text{stat})_{-0.07}^{+0.11}(\\text{sys})$%. This ratio is larger than most theoretical predictions by factors ranging from 1.5-3, but is consistent with the only other experimental measurement. From the reported ratio we calculate the partial width and electromagnetic transition magnetic moment for $\\Sigma^0(1385) \\to \\Lambda\\gamma$.

Keller, Dustin; Adhikari, Krishna; Adikaram-Mudiyanselage, Dasuni; Aghasyan, Mher; Amaryan, Moscov; Baghdasaryan, Hovhannes; Ball, J P; Ball, Jacques; Battaglieri, Marco; Batourine, V; Bedlinskiy, Ivan; Bennett, Robert; Biselli, Angela; Branford, Derek; Briscoe, Wilbert; Brooks, William; Burkert, Volker; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cole, Philip; Contalbrigo, Marco; Crede, Volker; D& #x27; Angelo, Annalisa; Daniel, AJI; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Dey, Biplap; Dickson, Richard; Djalali, Chaden; Doughty, David; Dupre, Raphael; Egiyan, Hovanes; El Alaoui, Ahmed; Elfassi, Lamiaa; Eugenio, Paul; Fedotov, Gleb; Fegan, Stuart; Forest, Tony; Gabrielyan, Marianna; Gavalian, Gagik; Gevorgyan, Nerses; Giovanetti, Kevin; Girod, Francois-Xavier; Gohn, Wesley; Golovach, Evgeny; Gothe, Ralf; Graham, Lewis; Guidal, Michel; Guegan, Baptiste; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Isupov, Evgeny; Jawalkar, Sucheta; Jenkins, David; Jo, Hyon-Suk; Joo, Kyungseon; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Konczykowski, Piotr; Kubarovsky, Valery; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lu, Haiyun; MacGregor, Ian; Markov, Nikolai; McAndrew, Josephine; KcKinnon, Bryan; Meyer, Curtis; Micherdzinska, Anna; Mirazita, Marco; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrison, Brian; Moutarde, Herve; Munevar Espitia, Edwin; Nadel-Turonski, Pawel; Ni, Andrey; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Osipenko, Mikhail; Ostrovidov, Alexander; Paremuzyan, Rafayel; Park, Kijun; Park, Sungkyun; Pasyuk, Eugene; Pasyuk, Evgueni; Pereira, Sergio; Pappalardo, Luciano; Pisano, Silvia; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Procureur, Sebastien; Protopopescu, Dan; Raue, Brian; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Seraydaryan, Heghine; Sharabian, Youri; Smith, Elton; Smith, Gregory; Sober, Daniel; Stepanyan, Stepan; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tang, Wei; Taylor, Charles; Vernarsky, Brian; Vineyard, Michael; Voutier, Eric; Weinstein, Lawrence; Watts, Daniel; Wood, Michael; Zachariou, Nicholas; Zana, Lorenzo; Zhao, Bo

2011-04-01T23:59:59.000Z