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Note: This page contains sample records for the topic "velocity wave probe" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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1

Wave VelocityWave Velocity Diff t f ti l l itDifferent from particle velocity  

E-Print Network [OSTI]

Wave VelocityWave Velocity v=/T =f Diff t f ti l l itDifferent from particle velocity Depends on the medium in which the wave travelsDepends on the medium in which the wave travels stringaonvelocity F v of Waves11-8. Types of Waves Transverse wave Longitudinal wave Liu UCD Phy1B 2014 37 #12;Sound Wave

Yoo, S. J. Ben

2

Millimeter-wave active probe  

DOE Patents [OSTI]

A millimeter-wave active probe for use in injecting signals with frequencies above 50GHz to millimeter-wave and ultrafast devices and integrated circuits including a substrate upon which a frequency multiplier consisting of filter sections and impedance matching sections are fabricated in uniplanar transmission line format. A coaxial input and uniplanar 50 ohm transmission line couple an approximately 20 GHz input signal to a low pass filter which rolls off at approximately 25 GHz. An input impedance matching section couples the energy from the low pass filter to a pair of matched, antiparallel beam lead diodes. These diodes generate odd-numberd harmonics which are coupled out of the diodes by an output impedance matching network and bandpass filter which suppresses the fundamental and third harmonics and selects the fifth harmonic for presentation at an output.

Majidi-Ahy, Gholamreza (Sunnyvale, CA); Bloom, David M. (Portola Valley, CA)

1991-01-01T23:59:59.000Z

3

Field comparison of the point velocity probe with other groundwater velocity measurement methods  

E-Print Network [OSTI]

Field testing of a new tool for measuring groundwater velocities at the centimeter scale, the point velocity probe (PVP), was undertaken at Canadian Forces Base, Borden, Ontario, Canada. The measurements were performed in ...

Labaky, W.; Devlin, J. F.; Gillham, R. W.

2009-03-14T23:59:59.000Z

4

Crust and Upper Mantle P Wave Velocity Structure Beneath Valles...  

Open Energy Info (EERE)

Crust and Upper Mantle P Wave Velocity Structure Beneath Valles Caldera, New Mexico- Results from the Jemez Teleseismic Tomography Experiment Jump to: navigation, search OpenEI...

5

P wave velocity variations in the Coso region, California, derived...  

Open Energy Info (EERE)

Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: P wave velocity variations in the Coso region, California, derived from local earthquake...

6

Estimating propagation velocity through a surface acoustic wave sensor  

SciTech Connect (OSTI)

Techniques are described for estimating the propagation velocity through a surface acoustic wave sensor. In particular, techniques which measure and exploit a proper segment of phase frequency response of the surface acoustic wave sensor are described for use as a basis of bacterial detection by the sensor. As described, use of velocity estimation based on a proper segment of phase frequency response has advantages over conventional techniques that use phase shift as the basis for detection.

Xu, Wenyuan (Oakdale, MN); Huizinga, John S. (Dellwood, MN)

2010-03-16T23:59:59.000Z

7

Uppermost mantle P wave velocities beneath Turkey and Iran  

SciTech Connect (OSTI)

The uppermost mantle P wave velocities beneath Turkey and Iran were estimated by applying the conventional travel time-distance relation method to arrival times of well located earthquakes recorded at a few stations. The average uppermost mantle P wave velocity under Turkey is estimated from two stations of the World Wide Standardized Seismograph Network (WWSSN), Istanbul and Tabriz. The data are consistent with a crust of uniform, but poorly determined, thickness and an uppermost mantle P wave velocity of 7.73 +- 0.08 km/s. This velocity is very similar to that for the Aegean Sea and suggests that its structure could be closely related to that beneath Turkey. For Iran, the results calculated from travel times to three WWSSN stations, Meshed, Shiraz, and Tabriz, can be explained by a crust dipping toward the south-southeast at about 1/sup 0/ with an uppermost mantle P wave velocity of 8.0 +- 0.1 km/s. If the crustal thickness were 34 km in the north it would reach about 49 km in the south. Based on these uppermost mantle velocities, the temperature at Moho beneath Turkey is probably close to the melting temperature of peridotite but that beneath Iran is probably lower.

Chen, C.; Chen, W.; Molnar, P.

1980-01-01T23:59:59.000Z

8

Impact of Phase Transitions on P Wave Velocities  

SciTech Connect (OSTI)

In regions where a high pressure phase is in equilibrium with a low pressure phase, the bulk modulus defined by the P-V relationship is greatly reduced. Here we evaluate the effect of such transitions on the P wave velocity. A model, where cation diffusion is the rate limiting factor, is used to project laboratory data to the conditions of a seismic wave propagating in the two-phase region. We demonstrate that for the minimum expected effect there is a significant reduction of the seismic velocity, as large as 10% over a narrow depth range.

D Weidner; L Li

2011-12-31T23:59:59.000Z

9

Matter wave optical techniques for probing many-body targets  

E-Print Network [OSTI]

This thesis reports on our investigation of the uses of matter waves to probe many-body targets. We begin by discussing decoherence in an atom interferometer, in which a free gas acts as a refractive medium for a matter ...

Sanders, Scott Nicholas

2010-01-01T23:59:59.000Z

10

Velocity bunching in travelling wave accelerator with low acceleration gradient  

E-Print Network [OSTI]

We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed electron beam with symmetrical longitudinal distribution and low energy spread. We also present a transverse emittance compensation scheme to compensate the emittance growth caused by the increasing of the space charge force in the compressing process that is easy to be adjusted for different compressing factors.

Huang, Rui-Xuan; Li, Wei-Wei; Jia, Qi-Ka

2013-01-01T23:59:59.000Z

11

Warm wave breaking of nonlinear plasma waves with arbitrary phase velocities C. B. Schroeder, E. Esarey, and B. A. Shadwick  

E-Print Network [OSTI]

Warm wave breaking of nonlinear plasma waves with arbitrary phase velocities C. B. Schroeder, E, collisionless plasma is developed to analyze nonlinear plasma waves excited by intense drive beams. The maximum amplitude and wavelength are calculated for nonrelativistic plasma temperatures and arbitrary plasma wave

Geddes, Cameron Guy Robinson

12

Surface acoustic wave probe implant for predicting epileptic seizures  

DOE Patents [OSTI]

A system and method for predicting and avoiding a seizure in a patient. The system and method includes use of an implanted surface acoustic wave probe and coupled RF antenna to monitor temperature of the patient's brain, critical changes in the temperature characteristic of a precursor to the seizure. The system can activate an implanted cooling unit which can avoid or minimize a seizure in the patient.

Gopalsami, Nachappa (Naperville, IL); Kulikov, Stanislav (Sarov, RU); Osorio, Ivan (Leawood, KS); Raptis, Apostolos C. (Downers Grove, IL)

2012-04-24T23:59:59.000Z

13

Nondestructive millimeter wave imaging and spectroscopy using dielectric focusing probes  

SciTech Connect (OSTI)

A tool for interrogating objects over a wide band of frequencies with subwavelength resolution at small standoff distances (near field region) in the transmission mode using a single source and detector measurement setup in the millimeter wave band is presented. The design utilizes optics like principles for guiding electromagnetic millimeter waves from large cross-sectional areas to considerably smaller sub-wavelength areas. While plano-convex lenses can be used to focus waves to a fine resolution, they usually require a large stand-off distance thus resulting in alignment and spacing issues. The design procedure and simulation analysis of the focusing probes are presented in this study along with experimental verification of performance and imaging and spectroscopy examples. Nondestructive evaluation will find benefit from such an apparatus including biological tissue imaging, electronic package integrity testing, composite dielectric structure evaluation for defects and microfluidic sensing.

Hejase, Jose A.; Shane, Steven S.; Park, Kyoung Y.; Chahal, Premjeet [Terahertz Systems Laboratory (TeSLa) - Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI 48823 (United States)

2014-02-18T23:59:59.000Z

14

Electrical impedance string probes for two-phase void and velocity measurements. [PWR  

SciTech Connect (OSTI)

An instrumentation scheme has been developed to measure two-phase flow velocity and void fraction during the refill/reflood stages of a loss-of-coolant accident in experimental test facilities. The instrumentation's principle of operation was based on measurement of the electrical impedance of two-phase mixtures. Two-phase velocity is estimated by time-of-flight analysis of signals from two spatially separate sensors. A relative capacitive technique was employed to measure void fraction. The impedance sensor consists of a pair of stainless steel wires strung back and forth across a stainless steel frame. This sensor was dubbed string probe for this reason. The string probe was designed to withstand temperatures of 350/sup 0/C, thermal transients of approx. 300/sup 0/C/s, and severe fluid- and condensation-induced shocks.

Hardy, J E; Hylton, J O

1982-05-01T23:59:59.000Z

15

Orthogonal-Phase-Velocity Propagation of Electromagnetic Plane Waves  

E-Print Network [OSTI]

In an isotropic, homogeneous, nondissipative, dielectric-magnetic medium that is simply moving with respect to an inertial reference frame, planewave solutions of the Maxwell curl postulates can be such that the phase velocity and the time-averaged Poynting vector are mutually orthogonal. Orthogonal-phase-velocity propagation thus adds to the conventional positive-phase-velocity propagation and the recently discovered negative-phase-velocity propagation that is associated with the phenomenon of negative refraction.

Tom G. Mackay; Akhlesh Lakhtakia

2005-11-30T23:59:59.000Z

16

Variation of seismic-wave velocities in westerly granite under stress  

E-Print Network [OSTI]

-wave Results. S-wave Results. SUMMARY. REFERENCES. . . . :. 10 . . . . 13 . . . . . . . . 17 . . . . . 21 . . . . . 24 . . . . . 24 . . . . . 28 . . . . . 35 . . . . . . . 36 LIST OF TABLES Page TABLE la. Compressional-wave velocities, Vp.... . 17 Figure 7 Crosscorrelation between two P-wave traces along one direction at two different pressure levels to determine the relative time delays. . . . . 20 Figure 8. (a, b and c). P-wave traces measured at the center of the faces along x-, y...

Al-Shaibani, Abdulaziz Muhareb

1994-01-01T23:59:59.000Z

17

The Electric Field and Waves Instruments on the Radiation Belt Storm Probes Mission  

E-Print Network [OSTI]

The Electric Fields and Waves (EFW) Instruments on the two Radiation Belt Storm Probe (RBSP) spacecraft (recently renamed the Van Allen Probes) are designed to measure three dimensional quasi-static and low frequency ...

Wygant, J. R.

18

Argon–oxygen dc magnetron discharge plasma probed with ion acoustic waves  

SciTech Connect (OSTI)

The precise determination of the relative concentration of negative ions is very important for the optimization of magnetron sputtering processes, especially for those undertaken in a multicomponent background produced by adding electronegative gases, such as oxygen, to the discharge. The temporal behavior of an ion acoustic wave excited from a stainless steel grid inside the plasma chamber is used to determine the relative negative ion concentration in the magnetron discharge plasma. The phase velocity of the ion acoustic wave in the presence of negative ions is found to be faster than in a pure argon plasma, and the phase velocity increases with the oxygen partial pressure. Optical emission spectroscopy further confirms the increase in the oxygen negative ion density, along with a decrease in the argon positive ion density under the same discharge conditions. The relative negative ion concentration values measured by ion acoustic waves are compared with those measured by a single Langmuir probe, and a similarity in the results obtained by both techniques is observed.

Saikia, Partha, E-mail: partha.008@gmail.com; Saikia, Bipul Kumar; Goswami, Kalyan Sindhu [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur, Kamrup, Assam 782 402 (India); Phukan, Arindam [Madhabdev College, Narayanpur, Lakhimpur, Assam 784164 (India)

2014-05-15T23:59:59.000Z

19

A restoration model of distorted electron density in wave-cutoff probe measurement  

SciTech Connect (OSTI)

This study investigates the problem of electron density distortion and how the density can be restored in a wave-cutoff probe. Despite recent plasma diagnostics research using a wave-cutoff probe, the problem of electron density distortion caused by plasma conditions has not been resolved. Experimental results indicate that electron density measured using the wave-cutoff method is highly susceptible to variations in the probe tip gap. This electron density distortion is caused by the bulk plasma disturbance between probe tips, and it must be removed for calculating the absolute electron density. To do this, a detailed analytic model was developed using the power balance equation near probe tips. This model demonstrates the characteristics of plasma distortion in wave-cutoff probe measurement and successfully restored the absolute value of electron density with varying probe tip gaps.

Jun, Hyun-Su, E-mail: mtsconst@kaist.ac.kr; Lee, Yun-Seong [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)] [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)

2014-02-15T23:59:59.000Z

20

Shear wave seismic velocity profiling and depth to water table earthquake site  

E-Print Network [OSTI]

..................................................................................................... 6 Summary of seismic refraction/reflection methodsShear wave seismic velocity profiling and depth to water table ­ earthquake site response measurements for Valley County, Idaho Lee M. Liberty and Gabriel M. Gribler, Boise State University Center

Barrash, Warren

Note: This page contains sample records for the topic "velocity wave probe" 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

Wave Packet for Massless Fermions and its Implication to the Superluminal Velocity Statistics of Neutrino  

E-Print Network [OSTI]

Non-dispersive wave packet for massless fermions is formulated on the basis of squeezed coherent states that are put in a form of common eigenfunction for the Hamiltonian and the helicity operator, starting from the Dirac equation. The wave packet thus constructed is demonstrated to propagate at a constant velocity as that of light. This explicit expression of wave packet for the massless fermions can facilitate theoretical analysis of problems where a wave packet is of formal significance. Furthermore, extensive wave packet may result in a superluminal velocity statistics if determined from the time-of-flight measurement, as recently done on muon neutrinos, when a threshold particle flux or energy transfer, which is eventually referred to the propagation of wave packet, to invoke a detection event is assumed.

Kelin Wang; Zexian Cao

2012-01-06T23:59:59.000Z

22

UT of bimetallic welds by shear horizontal waves and electromagnetic ultrasonic (EMUS) probes  

SciTech Connect (OSTI)

Bimetallic transition welds include in most cases besides the austenitic weldment an austenitic buttering. Their inspection by ultrasound is strongly complicated by a high degree of elastic anisotropy. The elastic anisotropy results in phase and group velocities of the elastic wave-modes, which are functions of the propagation direction inside the weld metal and which cause skewing of the sound beams. The coarse grain structure leads to enhanced scattering. Furthermore, there exists a mismatch of the acoustical impedances between the weld metal and the base metal, which depends on the angle of incidence at the interface base metal/weld metal and weld metal/buttering. Due to these facts up to now using standard UT-techniques only the HAZ`s are inspected from both sides. In many cases dissimilar metal welds are only accessible from one side. Therefore, US-techniques are necessary which are capable to inspect the whole weld even if there is only access from one side. By improvement of the technology of the EMUS-probes and of the EMUS-instrumentation for the US-transduction of SH-waves a reliable technique for the ISI of dissimilar metal welds and also of austenitic welds is available. The contribution will shortly introduce into the physical basis of the SH-wave technique and present the results of test specimen measurements. The main part of the paper will report about the experiences and the results of field applications in different nuclear power plants.

Huebschen, G.; Salzburger, H.J.; Kroening, M. [Fraunhofer-Inst. fuer Zerstoerungsfreie Pruefverfahren, Saarbruecken (Germany)

1994-12-31T23:59:59.000Z

23

Measurement of shear wave velocity of heavy oil De-hua Han, Jiajin Liu, University of Houston  

E-Print Network [OSTI]

for measurement of fluid velocity is to measure the travel time of the transmission wave and then the velocity can water, has been used and is good for P-wave measurement for a lot of fluid samples. But the transmission the principle of this method. The shear wave transducer is coupled with a buffer made of some kind of plastic

24

Near-Surface Shear-Wave Velocity Measurements in Unlithified Sediment  

E-Print Network [OSTI]

with an average S-wave velocity of 600 ft/sec in the top 30 meters as having a relatively high risk for amplifying destructive earthquake waves (Hunter et al., 2010). S-wave studies have also been used to identify subsidence and liquefaction risks for wind-turbine... the method is more challenging geometrically (Kanli, 2008). In fact, it has become common practice to run geological core samples through CAT scans to help determine composition and image bedforms for oil exploration (Stewart, 1991). Medical...

Rickards, Benjamin Thomas

2011-05-31T23:59:59.000Z

25

A New Global Rayleigh and Love Wave Group Velocity Dataset For Constraining Lithosphere Properties  

E-Print Network [OSTI]

A New Global Rayleigh and Love Wave Group Velocity Dataset For Constraining Lithosphere Properties features and fit our data very well. This dataset will be used to constrain lithospheric structure globally the global datasets used in Ritzwoller et al. (2002) already consist of more than 100,000 paths, the nature

Laske, Gabi

26

Increase of shear wave velocity before the 1998 eruption of Merapi volcano (Indonesia)  

E-Print Network [OSTI]

Increase of shear wave velocity before the 1998 eruption of Merapi volcano (Indonesia) U. Wegler,1 of the edifice of Merapi volcano (Java, Indonesia) before its eruption in 1998 by analyzing multiply scattered eruption of Merapi volcano (Indonesia), Geophys. Res. Lett., 33, L09303, doi:10.1029/2006GL025928. 1

Snieder, Roel

27

Effects of neutral interactions on velocity-shear-driven plasma waves  

SciTech Connect (OSTI)

In a laboratory experiment, we demonstrate the substantial effects that collisions between charged and neutral particles have on low-frequency (?{sub i}????????{sub e}) shear-driven electrostatic lower hybrid waves in a plasma. We establish a strong (up to 2.5?kV/m) highly localized electric field with a length scale shorter than the ion gyroradius, so that the ions in the plasma, unlike the electrons, do not develop the full E?×?B drift velocity. The resulting shear in the particle velocities initiates the electron-ion hybrid (EIH) instability, and we observe the formation of strong waves in the vicinity of the shear with variations in plasma densities of 10% or greater. Our experimental configuration allows us to vary the neutral background density by more than a factor of two while holding the charged particle density effectively constant. Not surprisingly, increasing the neutral density decreases the growth rate/saturation amplitude of the waves and increases the threshold electric field necessary for wave formation, but the presence of neutrals affects the dominant wave frequency as well. We show that a 50% increase in the neutral density decreases the wave frequency by 20% while also suppressing the electric field dependence of the frequency that is observed when fewer neutrals are present. The majority of these effects, as well as the values of the frequencies we observe, closely match the predictions of previously developed linear EIH instability theory, for which we present the results of a numerical solution.

Enloe, C. L. [Physics Department, US Air Force Academy, Colorado Springs, Colorado 80840 (United States); Tejero, E. M.; Amatucci, W. E.; Crabtree, C.; Ganguli, G. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Sotnikov, V. [Sensors Directorate, Air Force Research Laboratory, Dayton, Ohio 45433 (United States)

2014-06-15T23:59:59.000Z

28

Standard practice for measuring the ultrasonic velocity in polyethylene tank walls using lateral longitudinal (LCR) waves  

E-Print Network [OSTI]

1.1 This practice covers a procedure for measuring the ultrasonic velocities in the outer wall of polyethylene storage tanks. An angle beam lateral longitudinal (LCR) wave is excited with wedges along a circumferential chord of the tank wall. A digital ultrasonic flaw detector is used with sending-receiving search units in through transmission mode. The observed velocity is temperature corrected and compared to the expected velocity for a new, unexposed sample of material which is the same as the material being evaluated. The difference between the observed and temperature corrected velocities determines the degree of UV exposure of the tank. 1.2 The practice is intended for application to the outer surfaces of the wall of polyethylene tanks. Degradation typically occurs in an outer layer approximately 3.2-mm (0.125-in.) thick. Since the technique does not interrogate the inside wall of the tank, wall thickness is not a consideration other than to be aware of possible guided (Lamb) wave effects or reflection...

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

29

Generation of lower hybrid and whistler waves by an ion velocity ring distribution  

SciTech Connect (OSTI)

Using fully kinetic simulations in two and three spatial dimensions, we consider the generation and nonlinear evolution of lower hybrid waves produced by a cold ion ring velocity distribution in a low beta plasma. We show that the initial development of the instability is very similar in two and three dimensions and not significantly modified by electromagnetic effects, consistent with linear theory. At saturation, the level of electric field fluctuations is a small fraction of the background thermal energy; the electric field and corresponding density fluctuations consist of long, field-aligned striations. Energy extracted from the ring goes primarily into heating the background ions and the electrons at comparable rates. The initial growth and saturation of the magnetic components of the lower hybrid waves are related to the electric field components, consistent with linear theory. As the growing electric field fluctuations saturate, parallel propagating whistler waves develop by the interaction of two lower hybrid waves. At later times, these whistlers are replaced by longer wavelength, parallel propagating whistlers that grow through the decay of the lower hybrid fluctuations. Wave matching conditions demonstrate these conversion processes of lower hybrid waves to whistler waves. The conversion efficiency (=ratio of the whistler wave energy to the energy in the saturated lower hybrid waves) is computed and found to be significant ({approx}15%) for the parameters of the three-dimensional simulation (and even larger in the two-dimensional simulation), although when normalized in terms of the initial kinetic energy in the ring ions the overall efficiency is very small (<10{sup -4}). The results are compared with relevant linear and nonlinear theory.

Winske, D.; Daughton, W. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-07-15T23:59:59.000Z

30

The nonlinear theory of slow-wave electron cyclotron masers with inclusion of the beam velocity spread  

SciTech Connect (OSTI)

The nonlinear theory of slow-wave electron cyclotron masers (ECM) with an initially straight electron beam is developed. The evolution equation of the nonlinear beam electron energy is derived. The numerical studies of the slow-wave ECM efficiency with inclusion of Gaussian beam velocity spread are presented. It is shown that the velocity spread reduces the interaction efficiency. -- Highlights: •The theory of slow-wave electron cyclotron masers is considered. •The calculation of efficiency under the resonance condition is presented. •The efficiency under Gaussian velocity spreads has been obtained.

Kong, Ling-Bao, E-mail: konglingbao@gmail.com [School of Science, Beijing University of Chemical Technology, Beijing 100029 (China) [School of Science, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Key Laboratory of Environmentally Harmful Chemicals Assessment, Beijing University of Chemical Technology, Beijing 100029 (China); Wang, Hong-Yu [School of Physics, Anshan Normal University, Anshan 114005 (China)] [School of Physics, Anshan Normal University, Anshan 114005 (China); Hou, Zhi-Ling, E-mail: houzl@mail.buct.edu.cn [School of Science, Beijing University of Chemical Technology, Beijing 100029 (China) [School of Science, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Key Laboratory of Environmentally Harmful Chemicals Assessment, Beijing University of Chemical Technology, Beijing 100029 (China); Jin, Hai-Bo [School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Du, Chao-Hai [Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)] [Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)

2013-12-15T23:59:59.000Z

31

Exploring Classically Chaotic Potentials with a Matter Wave Quantum Probe  

SciTech Connect (OSTI)

We study an experimental setup in which a quantum probe, provided by a quasimonomode guided atom laser, interacts with a static localized attractive potential whose characteristic parameters are tunable. In this system, classical mechanics predicts a transition from regular to chaotic behavior as a result of the coupling between the different degrees of freedom. Our experimental results display a clear signature of this transition. On the basis of extensive numerical simulations, we discuss the quantum versus classical physics predictions in this context. This system opens new possibilities for investigating quantum scattering, provides a new testing ground for classical and quantum chaos, and enables us to revisit the quantum-classical correspondence.

Gattobigio, G. L. [Laboratoire de Collisions Agregats Reactivite, CNRS UMR 5589, IRSAMC, Universite de Toulouse (UPS), 118 Route de Narbonne, 31062 Toulouse CEDEX 4 (France); Laboratoire Kastler Brossel, Ecole Normale Superieure, 24 rue Lhomond, 75005 Paris (France); Couvert, A. [Laboratoire Kastler Brossel, Ecole Normale Superieure, 24 rue Lhomond, 75005 Paris (France); Georgeot, B. [Laboratoire de Physique Theorique (IRSAMC), Universite de Toulouse (UPS), 31062 Toulouse (France); CNRS, LPT UMR5152 (IRSAMC), 31062 Toulouse (France); Guery-Odelin, D. [Laboratoire de Collisions Agregats Reactivite, CNRS UMR 5589, IRSAMC, Universite de Toulouse (UPS), 118 Route de Narbonne, 31062 Toulouse CEDEX 4 (France)

2011-12-16T23:59:59.000Z

32

Green's Functions for Surface Waves in a Generic Velocity Structure 1 Victor C. Tsai and Sarun Atiganyanun* 3  

E-Print Network [OSTI]

1 Green's Functions for Surface Waves in a Generic Velocity Structure 1 and Green's functions have been well established 14 for many decades. However, or Green's function surface displacement. We address this gap in the 19 literature

33

Upper mantle structure of South America from joint inversion of waveforms and fundamental mode group velocities of Rayleigh waves  

E-Print Network [OSTI]

Upper mantle structure of South America from joint inversion of waveforms and fundamental mode tomographic S wave velocity model for the upper mantle beneath South America is presented. We developed three-dimensional (3-D) upper mantle S velocity model and a Moho depth model for South America, which

van der Lee, Suzan

34

Optical pin apparatus for measuring the arrival time and velocity of shock waves and particles  

DOE Patents [OSTI]

An apparatus for the detection of the arrival and for the determination of the velocity of disturbances such as shock-wave fronts and/or projectiles. Optical pins using fluid-filled microballoons as the light source and an optical fiber as a link to a photodetector have been used to investigate shock-waves and projectiles. A microballoon filled with a noble gas is affixed to one end of a fiber-optic cable, and the other end of the cable is attached to a high-speed streak camera. As the shock-front or projectile compresses the microballoon, the gas inside is heated and compressed producing a bright flash of light. The flash of light is transmitted via the optic cable to the streak camera where it is recorded. One image-converter streak camera is capable of recording information from more than 100 microballoon-cable combinations simultaneously.

Benjamin, R.F.

1983-10-18T23:59:59.000Z

35

Ion Bernstein waves in a plasma with a kappa velocity distribution  

SciTech Connect (OSTI)

Using a Vlasov-Poisson model, a numerical investigation of the dispersion relation for ion Bernstein waves in a kappa-distributed plasma has been carried out. The dispersion relation is found to depend significantly on the spectral index of the ions, ?{sub i}, the parameter whose smallness is a measure of the departure from thermal equilibrium of the distribution function. Over all cyclotron harmonics, the typical Bernstein wave curves are shifted to higher wavenumbers (k) if ?{sub i} is reduced. For waves whose frequency lies above the lower hybrid frequency, ?{sub LH}, an increasing excess of superthermal particles (decreasing ?{sub i}) reduces the frequency, ?{sub peak}, of the characteristic peak at which the group velocity vanishes, while the associated k{sub peak} is increased. As the ratio of ion plasma to cyclotron frequency (?{sub pi}/?{sub ci}) is increased, the fall-off of ? at large k is smaller for lower ?{sub i} and curves are shifted towards larger wavenumbers. In the lower hybrid frequency band and harmonic bands above it, the frequency in a low-?{sub i} plasma spans only a part of the intraharmonic space, unlike the Maxwellian case, thus exhibiting considerably less coupling between adjacent bands for low ?{sub i}. It is suggested that the presence of the ensuing stopbands may be a useful diagnostic for the velocity distribution characteristics. The model is applied to the Earth's plasma sheet boundary layer in which waves propagating perpendicularly to the ambient magnetic field at frequencies between harmonics of the ion cyclotron frequency are frequently observed.

Nsengiyumva, F.; Mace, R. L.; Hellberg, M. A. [School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4000 (South Africa)] [School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4000 (South Africa)

2013-10-15T23:59:59.000Z

36

The thin section rock physics: Modeling and measurement of seismic wave velocity on the slice of carbonates  

SciTech Connect (OSTI)

This paper discusses a new approach for investigating the seismic wave velocity of rock, specifically carbonates, as affected by their pore structures. While the conventional routine of seismic velocity measurement highly depends on the extensive laboratory experiment, the proposed approach utilizes the digital rock physics view which lies on the numerical experiment. Thus, instead of using core sample, we use the thin section image of carbonate rock to measure the effective seismic wave velocity when travelling on it. In the numerical experiment, thin section images act as the medium on which wave propagation will be simulated. For the modeling, an advanced technique based on artificial neural network was employed for building the velocity and density profile, replacing image's RGB pixel value with the seismic velocity and density of each rock constituent. Then, ultrasonic wave was simulated to propagate in the thin section image by using finite difference time domain method, based on assumption of an acoustic-isotropic medium. Effective velocities were drawn from the recorded signal and being compared to the velocity modeling from Wyllie time average model and Kuster-Toksoz rock physics model. To perform the modeling, image analysis routines were undertaken for quantifying the pore aspect ratio that is assumed to represent the rocks pore structure. In addition, porosity and mineral fraction required for velocity modeling were also quantified by using integrated neural network and image analysis technique. It was found that the Kuster-Toksoz gives the closer prediction to the measured velocity as compared to the Wyllie time average model. We also conclude that Wyllie time average that does not incorporate the pore structure parameter deviates significantly for samples having more than 40% porosity. Utilizing this approach we found a good agreement between numerical experiment and theoretically derived rock physics model for estimating the effective seismic wave velocity of rock.

Wardaya, P. D., E-mail: pongga.wardaya@utp.edu.my; Noh, K. A. B. M., E-mail: pongga.wardaya@utp.edu.my; Yusoff, W. I. B. W., E-mail: pongga.wardaya@utp.edu.my [Petroleum Geosciences Department, Universiti Teknologi PETRONAS, Tronoh, Perak, 31750 (Malaysia); Ridha, S. [Petroleum Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Perak, 31750 (Malaysia); Nurhandoko, B. E. B. [Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Dept. of Physics, Institute of Technology Bandung, Bandung, Indonesia and Rock Fluid Imaging Lab, Bandung (Indonesia)

2014-09-25T23:59:59.000Z

37

Stochastic simulation for the propagation of high-frequency acoustic waves through a random velocity field  

SciTech Connect (OSTI)

In-service inspection of Sodium-Cooled Fast Reactors (SFR) requires the development of non-destructive techniques adapted to the harsh environment conditions and the examination complexity. From past experiences, ultrasonic techniques are considered as suitable candidates. The ultrasonic telemetry is a technique used to constantly insure the safe functioning of reactor inner components by determining their exact position: it consists in measuring the time of flight of the ultrasonic response obtained after propagation of a pulse emitted by a transducer and its interaction with the targets. While in-service the sodium flow creates turbulences that lead to temperature inhomogeneities, which translates into ultrasonic velocity inhomogeneities. These velocity variations could directly impact the accuracy of the target locating by introducing time of flight variations. A stochastic simulation model has been developed to calculate the propagation of ultrasonic waves in such an inhomogeneous medium. Using this approach, the travel time is randomly generated by a stochastic process whose inputs are the statistical moments of travel times known analytically. The stochastic model predicts beam deviations due to velocity inhomogeneities, which are similar to those provided by a determinist method, such as the ray method.

Lu, B.; Darmon, M.; Leymarie, N.; Chatillon, S.; Potel, C. [CEA, LIST, F-91191 Gif-sur-Yvette (France); Laboratoire d'Acoustique de l'Universite du Maine (LAUM), UMR CNRS 6613, 72085 Le Mans Cedex 9 (France)

2012-05-17T23:59:59.000Z

38

MEASUREMENT OF COMPRESSIONAL-WAVE SEISMIC VELOCITIES IN 29 WELLS AT THE HANFORD SITE  

SciTech Connect (OSTI)

Check shot seismic velocity surveys were collected in 100 B/C, 200 East, 200-PO-1 Operational Unit (OU), and the Gable Gap areas in order to provide time-depth correlation information to aid the interpretation of existing seismic reflection data acquired at the Hanford Site (Figure 1). This report details results from 5 wells surveyed in fiscal year (FY) 2008, 7 wells in FY 2009, and 17 wells in FY 2010 and provides summary compressional-wave seismic velocity information to help guide future seismic survey design as well as improve current interpretations of the seismic data (SSC 1979/1980; SGW-39675; SGW-43746). Augmenting the check shot database are four surveys acquired in 2007 in support of the Bechtel National, Inc. Waste Treatment Plant construction design (PNNL-16559, PNNL-16652), and check shot surveys in three wells to support seismic testing in the 200 West Area (Waddell et al., 1999). Additional sonic logging was conducted during the late 1970s and early 1980s as part of the Basalt Waste Isolation Program (BWIP) (SSC 1979/1980) and check shot/sonic surveys as part of the safety report for the Skagit/Hanford Nuclear project (RDH/10-AMCP-0164). Check shot surveys are used to obtain an in situ measure of compressional-wave seismic velocity for sediment and rock in the vicinity of the well point, and provide the seismic-wave travel time to geologic horizons of interest. The check shot method deploys a downhole seismic receiver (geophone) to record the arrival of seismic waves generated by a source at the ground surface. The travel time of the first arriving seismic-wave is determined and used to create a time-depth function to correlate encountered geologic intervals with the seismic data. This critical tie with the underlying geology improves the interpretation of seismic reflection profile information. Fieldwork for this investigation was conducted by in house staff during the weeks of September 22, 2008 for 5 wells in the 200 East Area (Figure 2); June 1, 2009 for 7 wells in the 200-PO-1 OU and Gable Gap regions (see Figure 3 and Figure 4); and March 22, 2010 and April 19, 2010 for 17 wells in the 200 East, The initial scope of survey work was planned for Wells 299-EI8-1, 699-2-E14, 699-12-18, 699-16-51, 699-42-30, 699-53-55B, 699-54-18D, and 699-84-34B. Well 299-E18-1 could not be entered due to bent casing (prevented removal of the pump), wells 699-12-18 and 699-42-30 could not be safely reached by the logging truck, Well 699-16-51 was decommissioned prior to survey start, Well 699-53-55B did not have its pump pulled, and Wells 699-2-EI4, 699-54-18D, and 699-84-34B are artesian and capped with an igloo structure. Table 1 provides a list of wells that were surveyed and Figure 1 through Figure 5 show the well locations relative to the Hanford Site.

PETERSON SW

2010-10-08T23:59:59.000Z

39

Study on creating hydraulic tomography for crystalline rock using frequency dependent elastic wave velocity  

SciTech Connect (OSTI)

The objective of this study is to establish a technique to obtain hydraulic conductivity distribution in granite rock masses using seismic tomography. We apply the characteristic that elastic wave velocity disperses in fully saturated porous media on frequency and this velocity dispersion is governed by the hydraulic conductivity - this characteristic has been confirmed in laboratory experiments. The feasibility and design of the field experiment was demonstrated in a first step with numerical simulations. In a second step we applied the technique to the fractured granite at the Grimsel Test Site in Switzerland. The emphasis of the field campaign was on the evaluation of the range of applicability of this technique. The field campaign was structured in three steps, each one corresponding to a larger spatial scale. First, the seismic tomography was applied to a small area - the two boreholes were located at a distance of 1.5 m. In the following step, we selected a larger area, in which the distance of the boreholes amounts to 10 m and the field corresponds to a more complex geology. Finally we applied the testing to a field where the borehole distance was of the order of 75 m. We also drilled a borehole to confirm hydraulic characteristic and reviewed hydraulic model in the 1.5 m cross-hole location area. The results from the field campaign are presented and their application to the various fields are discussed and evaluated. (authors)

Yoshimura, K.; Sakashita, S. [Radioactive Waste Management Funding and Research Center, Tokyo (Japan); Ando, K.; Bruines, P. [Civil Engineering Technical Division, Obayashi Corporation, Tokyo (Japan); Blechschmidt, I. [National Cooperative for the Disposal of Radioactive Waste, Wettingen (Switzerland); Kickmaier, W. [University of Applied Sciences, Northern Switzerland, Brugg (Switzerland); Onishi, Y.; Nishiyama, S. [Graduate School of Engineering, Kyoto University, Kyoto (Japan)

2007-07-01T23:59:59.000Z

40

Approximate analytical method and its use for calculation of phase velocities of acoustic plane waves in crystals for example LiNbO3  

E-Print Network [OSTI]

By means of the offered analytical method the determinant relation for a phase velocities of elastic waves for an arbitrary propagation directions in a piezoelectric crystal are received. The phase velocities of three normal elastic waves for the crystal of LiNbO3 are calculated. Results of this calculation for each of waves are presented graphically in the form of the cards allowing easily to define phase velocities in any given direction in crystal.

A. A. Golubeva

2010-07-26T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Green's Functions for Surface Waves in a Generic Velocity Structure by Victor C. Tsai and Sarun Atiganyanun*  

E-Print Network [OSTI]

Short Note Green's Functions for Surface Waves in a Generic Velocity Structure by Victor C. Tsai displacement/stress eigenfunctions and Green's functions have been well established for many decades. However on frequency, or Green's function surface displacement. We address this gap in the liter- ature and here

42

Estimating near-surface shear wave velocities in Japan by applying seismic interferometry to KiK-net data  

E-Print Network [OSTI]

Estimating near-surface shear wave velocities in Japan by applying seismic interferometry to KiK-net throughout Japan by applying seismic interferometry to the data recorded with KiK-net, a strong motion network in Japan. Each KiK-net station has two receivers; one receiver on the surface and the other

Cerveny, Vlastislav

43

Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography  

SciTech Connect (OSTI)

In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

2012-01-10T23:59:59.000Z

44

Ultrasonic probe deployment device for increased wave transmission and rapid area scan inspections  

DOE Patents [OSTI]

An ultrasonic probe deployment device in which an ultrasound-transmitting liquid forms the portion of the ultrasonic wave path in contact with the surface being inspected (i.e., the inspection surface). A seal constrains flow of the liquid, for example preventing the liquid from surging out and flooding the inspection surface. The seal is not rigid and conforms to variations in the shape and unevenness of the inspection surface, thus forming a seal (although possibly a leaky seal) around the liquid. The probe preferably is held in place to produce optimum ultrasonic focus on the area of interest. Use of encoders can facilitate the production of C-scan area maps of the material being inspected.

DiMambro, Joseph; Roach, Dennis P; Rackow, Kirk A; Nelson, Ciji L; Dasch, Cameron J; Moore, David G

2013-02-12T23:59:59.000Z

45

Ultrasonic probe deployment device for increased wave transmission and rapid area scan inspections  

SciTech Connect (OSTI)

An ultrasonic probe deployment device in which an ultrasound-transmitting liquid forms the portion of the ultrasonic wave path in contact with the surface being inspected (i.e., the inspection surface). A seal constrains flow of the liquid, for example preventing the liquid from surging out and flooding the inspection surface. The seal is not rigid and conforms to variations in the shape and unevenness of the inspection surface, thus forming a seal (although possibly a leaky seal) around the liquid. The probe preferably is held in place to produce optimum ultrasonic focus on the area of interest. Use of encoders can facilitate the production of C-scan area maps of the material being inspected.

DiMambro, Joseph (Placitas, NM); Roach, Dennis P. (Albuquerque, NM); Rackow, Kirk A. (Albuquerque, NM); Nelson, Ciji L. (Albuquerque, NM); Dasch, Cameron J. (Boomfield Hills, MI); Moore, David G. (Albuquerque, NM)

2012-01-03T23:59:59.000Z

46

Development of a generalized correlation for phase-velocity measurements obtained from impedance-probe pairs in two-phase flow systems. [PWR  

SciTech Connect (OSTI)

A flag type electrical impedance probe has been developed at the Oak Ridge National Lab (ORNL) to measure liquid- and vapor-phase velocities in steam-water mixtures flowing through rod bundles. Measurements are made by utilizing the probes in pairs, installed in line, parallel to the flow direction, and extending out into the flow channel. The present study addresses performance difficulties by examining from a fundamental point of view the two-phase flow system which the impedance probes typically operate in. Specifically, the governing equations (continuity, momentum, energy) were formulated for both air-water and steam-water systems, and then subjected to a scaling analysis. The scaling analysis yielded the appropriate dimensionless parameters of significance in both kinds of systems. Additionally, with the aid of experimental data obtained at ORNL, those parameters of significant magnitude were established. As a result, a generalized correlation was developed for liquid and vapor phase velocities that makes it possible to employ the impedance probe velocity measurement technique in a wide variety of test configurations and fluid combinations.

Hsu, C.T.; Keshock, E.G.; McGill, R.N.

1983-01-01T23:59:59.000Z

47

Shear Wave Velocity Structure of Southern African Crust: Evidence for Compositional Heterogeneity within Archaean and Proterozoic Terrains  

SciTech Connect (OSTI)

Crustal structure in southern Africa has been investigated by jointly inverting receiver functions and Rayleigh wave group velocities for 89 broadband seismic stations spanning much of the Precambrian shield of southern Africa. 1-D shear wave velocity profiles obtained from the inversion yield Moho depths that are similar to those reported in previous studies and show considerable variability in the shear wave velocity structure of the lower part of the crust between some terrains. For many of the Archaean and Proterozoic terrains in the shield, S velocities reach 4.0 km/s or higher over a substantial part of the lower crust. However, for most of the Kimberley terrain and adjacent parts of the Kheis Province and Witwatersrand terrain, as well as for the western part of the Tokwe terrain, mean shear wave velocities of {le} 3.9 km/s characterize the lower part of the crust along with slightly ({approx}5 km) thinner crust. These findings indicate that the lower crust across much of the shield has a predominantly mafic composition, except for the southwest portion of the Kaapvaal Craton and western portion of the Zimbabwe Craton, where the lower crust is intermediate-to-felsic in composition. The parts of the Kaapvaal Craton underlain by intermediate-to-felsic lower crust coincide with regions where Ventersdorp rocks have been preserved, and thus we suggest that the intermediate-to-felsic composition of the lower crust and the shallower Moho may have resulted from crustal melting during the Ventersdorp tectonomagmatic event at c. 2.7 Ga and concomitant crustal thinning caused by rifting.

Kgaswane, E M; Nyblade, A A; Julia, J; Dirks, P H H M; Durrheim, R J; Pasyanos, M E

2008-11-11T23:59:59.000Z

48

Topographically induced internal solitary waves in a pycnocline: Ultrasonic probes and stereo-correlation measurements  

SciTech Connect (OSTI)

Internal solitary waves (ISWs) are large amplitude stable waves propagating in regions of high density gradients such as the ocean pycnocline. Their dynamics has often been investigated in two-dimensional approaches, however, their three-dimensional evolution is still poorly known. Experiments have been conducted in the large stratified water tank of CNRM-GAME to study the generation of ISWs in two academic configurations inspired by oceanic regimes. First, ultrasonic probes are used to measure the interfacial displacement in the two configurations. In the primary generation case for which the two layers are of constant density, the generation of ISWs is investigated in two series of experiments with varying amplitude and forcing frequency. In the secondary generation case for which the lower layer is stratified, the generation of ISWs from the impact of an internal wave beam on the pycnocline and their subsequent dynamics is studied. The dynamics of ISWs in these two regimes accords well with analytical approaches and numerical simulations performed in analogous configurations. Then, recent developments of a stereo correlation technique are used to describe the three-dimensional structure of propagating ISWs. In the primary generation configuration, small transverse effects are observed in the course of the ISW propagation. In the secondary generation configuration, larger transverse structures are observed in the interfacial waves dynamics. The interaction between interfacial troughs and internal waves propagating in the lower stratified layer are a possible cause for the generation of these structures. The magnitude of these transverse structures is quantified with a nondimensional parameter in the two configurations. They are twice as large in the secondary generation case as in the primary generation case.

Dossmann, Yvan, E-mail: yvan.dossmann@anu.edu.au [Research School of Earth Sciences, The Australian National University, Canberra 0200 (Australia) [Research School of Earth Sciences, The Australian National University, Canberra 0200 (Australia); CNRM-GAME, UMR3589 METEO-FRANCE and CNRS, 42 avenue Gaspard Coriolis, 31057 Toulouse Cedex 01 (France); Laboratoire d’Aérologie, 14 avenue Edouard Belin, 31400 Toulouse (France); Paci, Alexandre [CNRM-GAME, UMR3589 METEO-FRANCE and CNRS, 42 avenue Gaspard Coriolis, 31057 Toulouse Cedex 01 (France)] [CNRM-GAME, UMR3589 METEO-FRANCE and CNRS, 42 avenue Gaspard Coriolis, 31057 Toulouse Cedex 01 (France); Auclair, Francis [Laboratoire d’Aérologie, 14 avenue Edouard Belin, 31400 Toulouse (France)] [Laboratoire d’Aérologie, 14 avenue Edouard Belin, 31400 Toulouse (France); Lepilliez, Mathieu [CNRM-GAME, UMR3589 METEO-FRANCE and CNRS, 42 avenue Gaspard Coriolis, 31057 Toulouse Cedex 01 (France) [CNRM-GAME, UMR3589 METEO-FRANCE and CNRS, 42 avenue Gaspard Coriolis, 31057 Toulouse Cedex 01 (France); Laboratoire d’Aérologie, 14 avenue Edouard Belin, 31400 Toulouse (France); Institut de Mécanique des Fluides de Toulouse, 2 Allée Camille Soula, F-31400 Toulouse (France); Cid, Emmanuel [Laboratoire de Génie Chimique, UMR5503 INPT, UPS, CNRS, 4, Allée Emile Monso, F-31030 Toulouse (France)] [Laboratoire de Génie Chimique, UMR5503 INPT, UPS, CNRS, 4, Allée Emile Monso, F-31030 Toulouse (France)

2014-05-15T23:59:59.000Z

49

E-Print Network 3.0 - acoustic wave velocity Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

43.30.Ft, 43... short range was deemed desirable for isolating the effects of shallow water internal waves on acoustic... internal waves are not un- usual and it was ......

50

Probes  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FORPoints of Contact Privacy Points ofPrivateProbes

51

Quantitative degenerate four-wave mixing spectroscopy: Probes for molecular species  

SciTech Connect (OSTI)

Resonant degenerate four-wave mixing (DFWM) is currently the subject of intensive investigation as a sensitive diagnostic tool for molecular species. DFWM has the advantage of generating a coherent (beam-like) signal which results in null-background detection and provides excellent immunity to background-light interference. Since multiple one-photon resonances are involved in the signal generation process, the DFWM technique can allow sensitive detection of molecules via electronic, vibrational or rotational transitions. These properties combine to make DFWM a widely applicable diagnostic technique for the probing of molecular species. The authors are conducting fundamental and applied investigations of DFWM for quantitative measurements of trace species in reacting gases. During the past year, efforts have been focussed in two areas: (1) understanding the effects of collisional processes on the DFWM signal generation process, and (2) exploring the applicability of infrared DFWM to detect polyatomic molecules via rovibrational transitions.

Farrow, R.; Rakestraw, D.; Paul, P.; Lucht, R.; Danehy, P.; Friedman-Hill, E.; Germann, G. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01T23:59:59.000Z

52

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA. Volume V S-Wave Measurements in Borehole C4996 Seismic Records, Wave-Arrival Identifications and Interpreted S-Wave Velocity Profile.  

SciTech Connect (OSTI)

Velocity measurements in shallow sediments from ground surface to approximately 370 to 400 feet bgs were collected by Redpath Geophysics using impulsive S- and P-wave seismic sources (Redpath 2007). Measurements below this depth within basalt and sedimentary interbeds were made by UTA between October and December 2006 using the T-Rex vibratory seismic source in each of the three boreholes. Results of these measurements including seismic records, wave-arrival identifications and interpreted velocity profiles are presented in the following six volumes: I. P-Wave Measurements in Borehole C4993 II. P-Wave Measurements in Borehole C4996 III. P-Wave Measurements in Borehole C4997 IV. S-Wave Measurements in Borehole C4993 V. S-Wave Measurements in Borehole C4996 VI. S-Wave Measurements in Borehole C4997 In this volume (V), all S-wave measurements are presented that were performed in Borehole C4996 at the WTP with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver.

Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh

2007-06-06T23:59:59.000Z

53

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA. Volume VI S-Wave Measurements in Borehole C4997 Seismic Records, Wave-Arrival Identifications and Interpreted S-Wave Velocity Profile.  

SciTech Connect (OSTI)

Velocity measurements in shallow sediments from ground surface to approximately 370 to 400 feet bgs were collected by Redpath Geophysics using impulsive S- and P-wave seismic sources (Redpath 2007). Measurements below this depth within basalt and sedimentary interbeds were made by UTA between October and December 2006 using the T-Rex vibratory seismic source in each of the three boreholes. Results of these measurements including seismic records, wave-arrival identifications and interpreted velocity profiles are presented in the following six volumes: I. P-Wave Measurements in Borehole C4993 II. P-Wave Measurements in Borehole C4996 III. P-Wave Measurements in Borehole C4997 IV. S-Wave Measurements in Borehole C4993 V. S-Wave Measurements in Borehole C4996 VI. S-Wave Measurements in Borehole C4997 In this volume (VI), all S-wave measurements are presented that were performed in Borehole C4997 at the WTP with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver.

Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh

2007-06-06T23:59:59.000Z

54

Pump and probe waves in dynamic acousto-elasticity: Comprehensive description and comparison with nonlinear elastic theories  

E-Print Network [OSTI]

- static stress).1 For isotropic materials, the speed of sound change with stress levels allows onePump and probe waves in dynamic acousto-elasticity: Comprehensive description and comparison with nonlinear elastic theories J. Rivie`re,1,a) G. Renaud,2 R. A. Guyer,1,b) and P. A. Johnson1 1 Earth

55

Probing thermal waves on the free surface of various media: Surface Fluctuation Specular Reflection Spectroscopy  

E-Print Network [OSTI]

Thermal motion gives rise to fluctuations in free surfaces; the propagation of the thermally excited waves on such surfaces depends on the mechanical properties of the medium. Their measurement can therefore provide information on those properties. We have developed an optical tool to probe the thermally excited waves on free surfaces: Surface Fluctuation Specular Reflection (SFSR) spectroscopy. It consists in measuring the fluctuations in the position of a laser beam, which is specularly reflected onto the free surface of a medium, and is therefore sensitive to the roughness of that surface. We show how the measured signal is related to the medium properties. We also present measurements performed on Newtonian liquids as well as on a viscoelastic solid; we show that, in all cases, there is a very good agreement between experimental and computed spectra. SFSR thus applies to a broad range of materials. It moreover offers a very good temporal resolution and should provide a useful tool for dynamical measurements on complex fluids.

Astrid Tay; Caroline Thibierge; Danièle Fournier; Christian Frétigny; François Lequeux; Cécile Monteux; Jean-Paul Roger; Laurence Talini

2008-06-16T23:59:59.000Z

56

Probing the thermal character of analogue Hawking radiation for shallow water waves?  

E-Print Network [OSTI]

We study and numerically compute the scattering coefficients of shallow water waves blocked by a stationary counterflow. When the flow is transcritical, the coefficients closely follow Hawking's prediction according to which black holes should emit a thermal spectrum. We study how the spectrum deviates from thermality when reducing the maximal flow velocity, with a particular attention to subcritical flows since these have been recently used to test Hawking's prediction. For such flows, we show that the emission spectrum is strongly suppressed, and that its Planckian character is completely lost. For low frequencies, we also show that the scattering coefficients are dominated by elastic hydrodynamical channels. Our numerical results reproduce rather well the observations made by S. Weinfurtner {\\it et al.} in the Vancouver experiment. Nevertheless, we propose a new interpretation of what has been observed, as well as new experimental tests.

Florent Michel; Renaud Parentani

2014-09-15T23:59:59.000Z

57

Stress-wave velocity of wood-based panels: Effect of moisture,  

E-Print Network [OSTI]

for wood-based panel products. In the forest products industry, nondestructive evaluation (NDE) technology, Ross and Pellerin 1994). One NDE technique, which uses stress-wave propagation characteristics, has received considerable atten- tion. Stress-wave-based NDE techniques have been investi- gated extensively

58

Statistics of amplitude and fluid velocity of large and rare waves in the ocean  

E-Print Network [OSTI]

The understanding of large and rare waves in the ocean is becoming more important as these rare events are turning into more common observances. In order to design a marine structure or vehicle to withstand such a potentially ...

Suh, Il Ho

2007-01-01T23:59:59.000Z

59

Molecular extended thermodynamics of rarefied polyatomic gases and wave velocities for increasing number of moments  

SciTech Connect (OSTI)

Molecular extended thermodynamics of rarefied polyatomic gases is characterized by two hierarchies of equations for moments of a suitable distribution function in which the internal degrees of freedom of a molecule is taken into account. On the basis of physical relevance the truncation orders of the two hierarchies are proven to be not independent on each other, and the closure procedures based on the maximum entropy principle (MEP) and on the entropy principle (EP) are proven to be equivalent. The characteristic velocities of the emerging hyperbolic system of differential equations are compared to those obtained for monatomic gases and the lower bound estimate for the maximum equilibrium characteristic velocity established for monatomic gases (characterized by only one hierarchy for moments with truncation order of moments N) by Boillat and Ruggeri (1997) (?{sub (N)}{sup E,max})/(c{sub 0}) ??(6/5 (N?1/2 )),(c{sub 0}=?(5/3 k/m T)) is proven to hold also for rarefied polyatomic gases independently from the degrees of freedom of a molecule. -- Highlights: •Molecular extended thermodynamics of rarefied polyatomic gases is studied. •The relation between two hierarchies of equations for moments is derived. •The equivalence of maximum entropy principle and entropy principle is proven. •The characteristic velocities are compared to those of monatomic gases. •The lower bound of the maximum characteristic velocity is estimated.

Arima, Takashi, E-mail: tks@stat.nitech.ac.jp [Center for Social Contribution and Collaboration, Nagoya Institute of Technology (Japan); Mentrelli, Andrea, E-mail: andrea.mentrelli@unibo.it [Department of Mathematics and Research Center of Applied Mathematics (CIRAM), University of Bologna (Italy); Ruggeri, Tommaso, E-mail: tommaso.ruggeri@unibo.it [Department of Mathematics and Research Center of Applied Mathematics (CIRAM), University of Bologna (Italy)

2014-06-15T23:59:59.000Z

60

Discrimination of the effects of saturation and optical pumping in velocity-dependent pump-probe spectroscopy of rubidium: A simple analytical study  

SciTech Connect (OSTI)

This paper presents a simple analytical theory for the velocity-dependent pump-probe laser spectroscopy of {sup 87}Rb and {sup 85}Rb atoms where the pump and the probe beams are circularly or linearly polarized. The analytical solutions of the line shapes of the velocity-selective optical pumping spectroscopy [G. Moon and H. R. Noh, Phys. Rev. A 78, 032506 (2008)] and saturated absorption spectroscopy [G. Moon and H. R. Noh, J. Opt. Soc. Am. B 25, 701 (2008); 27, 1741 (2010)] obtained in the previous reports, expressed as a sum of several Lorentzian functions, could be approximated as one (or in some cases, two) Lorentzian function(s). In particular, the contributions of the saturation and optical pumping effects could be discriminated explicitly in these simple analytical solutions, which is not possible in existing theories such as Nakayama's model. The simple analytical results for the saturation spectroscopy were compared with experimental results, and good agreement between them was observed.

Noh, Heung-Ryoul [Department of Physics, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Moon, Geol; Jhe, Wonho [School of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of)

2010-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

QUASI-PERIODIC PROPAGATING SIGNALS IN THE SOLAR CORONA: THE SIGNATURE OF MAGNETOACOUSTIC WAVES OR HIGH-VELOCITY UPFLOWS?  

SciTech Connect (OSTI)

Since the discovery of quasi-periodic propagating oscillations with periods of order 3-10 minutes in coronal loops with TRACE and SOHO/EIT (and later with STEREO/EUVI and Hinode/EIS), they have been almost universally interpreted as evidence for propagating slow-mode magnetoacoustic waves in the low plasma {beta} coronal environment. Here we show that this interpretation is not unique, and that for coronal loops associated with plage regions (as opposed to sunspots), the presence of magnetoacoustic waves may not be the only cause for the observed quasi-periodicities. We focus instead on the ubiquitous, faint upflows at 50-150 km s{sup -1} that were recently discovered as blueward asymmetries of spectral line profiles in footpoint regions of coronal loops, and as faint disturbances propagating along coronal loops in EUV/X-ray imaging time series. These faint upflows are most likely driven from below and have been associated with chromospheric jets that are (partially) rapidly heated to coronal temperatures at low heights. These two scenarios (waves versus flows) are difficult to differentiate using only imaging data, but careful analysis of spectral line profiles indicates that faint upflows are likely responsible for some of the observed quasi-periodic oscillatory signals in the corona. We show that recent EIS measurements of intensity and velocity oscillations of coronal lines (which had previously been interpreted as direct evidence for propagating waves) are actually accompanied by significant oscillations in the line width that are driven by a quasi-periodically varying component of emission in the blue wing of the line. This faint additional component of blue-shifted emission quasi-periodically modulates the peak intensity and line centroid of a single Gaussian fit to the spectral profile with the same small amplitudes (respectively a few percent of background intensity and a few km s{sup -1}) that were previously used to infer the presence of slow-mode magnetoacoustic waves. Our results indicate that it is possible that a significant fraction of the quasi-periodicities observed with coronal imagers and spectrographs that have previously been interpreted as propagating magnetoacoustic waves are instead caused by these upflows. The different physical cause for coronal oscillations would significantly impact the prospects of successful coronal seismology using propagating disturbances in coronal loops.

De Pontieu, Bart [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Org. ADBS, Bldg. 252, Palo Alto, CA 94304 (United States); McIntosh, Scott W., E-mail: bdp@lmsal.co, E-mail: mscott@ucar.ed [High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307 (United States)

2010-10-20T23:59:59.000Z

62

Determination of elastic properties of a MnO{sub 2} coating by surface acoustic wave velocity dispersion analysis  

SciTech Connect (OSTI)

MnO{sub 2} is a material of interest in the development of high energy-density batteries, specifically as a coating material for internal 3D structures, thus ensuring rapid energy deployment. Its electrochemical properties have been mapped extensively, but there are, to the best of the authors' knowledge, no records of the elastic properties of thin film MnO{sub 2}. Impulsive stimulated thermal scattering (ISTS), also known as the heterodyne diffraction or transient grating technique, was used to determine the Young's modulus (E) and porosity (?) of a 500?nm thick MnO{sub 2} coating on a Si(001) substrate. ISTS is an all optical method that is able to excite and detect surface acoustic waves (SAWs) on opaque samples. From the measured SAW velocity dispersion, the Young's modulus and porosity were determined to be E?=?25?±?1?GPa and ?=42±1%, respectively. These values were confirmed by independent techniques and determined by a most-squares analysis of the carefully fitted SAW velocity dispersion. This study demonstrates the ability of the presented technique to determine the elastic parameters of a thin, porous film on an anisotropic substrate.

Sermeus, J.; Glorieux, C., E-mail: christ.glorieux@fys.kuleuven.be [Laboratory for Acoustics and Thermal Physics, KU Leuven, University of Leuven, Celestijnenlaan 200D, B-3001 Heverlee (Belgium); Sinha, R.; Vereecken, P. M. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Center for Surface Chemistry and Catalysis, KU Leuven, University of Leuven, Kasteelpark Arenberg 23, B-3001 Leuven (Belgium); Vanstreels, K. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium)

2014-07-14T23:59:59.000Z

63

12A.4 VERTICAL VELOCITY AND BUOYANCY CHARACTERISTICS OF ECHO PLUMES DETECTED BY AN AIRBORNE MM-WAVE RADAR IN THE CONVECTIVE  

E-Print Network [OSTI]

12A.4 VERTICAL VELOCITY AND BUOYANCY CHARACTERISTICS OF ECHO PLUMES DETECTED BY AN AIRBORNE MM-WAVE, is the availability of in situ thermodynamic and kinematic observations, and the direct observation of horizontal, as part of IHOP_02 (The International Water Vapor Project, Weckwerth et al 2003). The key radar

Geerts, Bart

64

KRONOSEISMOLOGY: USING DENSITY WAVES IN SATURN'S C RING TO PROBE THE PLANET'S INTERIOR  

SciTech Connect (OSTI)

Saturn's C ring contains multiple spiral patterns that appear to be density waves driven by periodic gravitational perturbations. In other parts of Saturn's rings, such waves are generated by Lindblad resonances with Saturn's various moons, but most of the wave-like C-ring features are not situated near any strong resonance with any known moon. Using stellar occultation data obtained by the Visual and Infrared Mapping Spectrometer on board the Cassini spacecraft, we investigate the origin of six unidentified C-ring waves located between 80,900 and 87,200 km from Saturn's center. By measuring differences in the waves' phases among the different occultations, we are able to determine both the number of arms in each spiral pattern and the speeds at which these patterns rotate around the planet. We find that all six of these waves have between two and four arms and pattern speeds between 1660 Degree-Sign day{sup -1} and 1861 Degree-Sign day{sup -1}. These speeds are too large to be attributed to any satellite resonance. Instead, they are comparable to the predicted pattern speeds of waves generated by low-order normal-mode oscillations within the planet. The precise pattern speeds associated with these waves should therefore provide strong constraints on Saturn's internal structure. Furthermore, we identify multiple waves with the same number of arms and very similar pattern speeds, indicating that multiple m = 3 and m = 2 sectoral (l = m) modes may exist within the planet.

Hedman, M. M.; Nicholson, P. D., E-mail: mmhedman@astro.cornell.edu [Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14850 (United States)

2013-07-01T23:59:59.000Z

65

Probing strong-field gravity and black holes with gravitational waves  

E-Print Network [OSTI]

Gravitational wave observations will be excellent tools for making precise measurements of processes that occur in very strong- field regions of space time. Extreme mass

Hughes, Scott A.

66

Train of high-power femtosecond pulses: Probe wave in a gas of prepared atoms  

E-Print Network [OSTI]

We present a new method for generating a regular train of ultrashort optical pulses in a prepared two-level medium. The train develops from incident monochromatic probe radiation travelling in a medium of atoms, which are in a quantum mechanical superposition of dressed internal states. In the frame of used linear theory for the probe radiation, the energy of individual pulses is an exponentially growing function of atom density and of interaction cross section. Pulse repetition rate is determined by the generalized Rabi frequency and can be around 1 THz and greater. We also show that the terms, extra to the dipole approximation, endow the gas by a new property: non-saturating dependence of refractive index on the dressing monochromatic field intensity. Contribution of these nonsaturating terms can be compatible with the main dipole approximation in the wavelength region of about ten micrometers (the range of CO_2 laser) or larger.

Gevorg Muradyan; A. Zh. Muradyan

2009-08-21T23:59:59.000Z

67

Downhole Measurements of Shear- and Compression-Wave Velocities in Boreholes C4993, C4996, C4997 and C4998 at the Waste Treatment Plant DOE Hanford Site.  

SciTech Connect (OSTI)

This report describes the procedures and the results of a series of downhole measurements of shear- and compression-wave velocities performed as part of the Seismic Boreholes Project at the site of the Waste Treatment Plant (WTP). The measurements were made in several stages from October 2006 through early February 2007. Although some fieldwork was carried out in conjunction with the University of Texas at Austin (UT), all data acquired by UT personnel are reported separately by that organization.

Redpath, Bruce B.

2007-04-27T23:59:59.000Z

68

Relation of the wave{propagation metric tensor to the curvatures of the slowness and ray{velocity surfaces  

E-Print Network [OSTI]

Relation of the wave{propagation metric tensor to the curvatures of the slowness and ray The contravariant components of the wave{propagation metric tensor equal half the second{order partial derivatives. The relations of the wave{propagation metric tensor to the curvature matrix and Gaussian curvature

Cerveny, Vlastislav

69

Gravity and the Collapse of the Wave Function: a Probe into Diósi-Penrose model  

E-Print Network [OSTI]

We investigate the Di\\'osi-Penrose (DP) proposal for connecting the collapse of the wave function to gravity. The DP model needs a free parameter, acting as a cut-off to regularize the dynamics, and the predictions of the model highly depend on the value of this cut-off. The Compton wavelength of a nucleon seems to be the most reasonable cut-off value since it justifies the non-relativistic approach. However, with this value, the DP model predicts an unrealistic high rate of energy increase. Thus, one either is forced to choose a much larger cut-off, which is not physically justified and totally arbitrary, or one needs to include dissipative effects in order to tame the energy increase. Taking the analogy with dissipative collisional decoherence seriously, we develop a dissipative generalization of the DP model. We show that even with dissipative effects, the DP model contradicts known physical facts, unless either the cut-off is kept artificially large, or one limits the applicability of the model to massive systems. We also provide an estimation for the mass range of this applicability.

Mohammad Bahrami; Andrea Smirne; Angelo Bassi

2014-08-27T23:59:59.000Z

70

Rogue waves for a long wave-short wave resonance model with multiple short waves  

E-Print Network [OSTI]

1 Rogue waves for a long wave-short wave resonance model with multiple short waves Hiu Ning Chan (1 waves; Long-short resonance PACS Classification: 02.30.Jr; 05.45.Yv; 47.35.Fg #12;2 ABSTRACT A resonance between long and short waves will occur if the phase velocity of the long wave matches the group velocity

71

In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels  

DOE Patents [OSTI]

An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web. 37 figs.

Hall, M.S.; Jackson, T.G.; Knerr, C.

1998-02-17T23:59:59.000Z

72

2011 Waves -1 STANDING WAVES  

E-Print Network [OSTI]

2011 Waves - 1 STANDING WAVES ON A STRING The objectives of the experiment are: · To show that standing waves can be set up on a string. · To determine the velocity of a standing wave. · To understand the differences between transverse and longitudinal waves. APPARATUS: Buzzer board with string, meter stick

Glashausser, Charles

73

PHYSICAL REVIEW E 85, 051302 (2012) Probing the shear-band formation in granular media with sound waves  

E-Print Network [OSTI]

, the application of these experimental methods to real 3D opaque granular materials appears difficult. Sound waves [13­17]. Speed measurements of long-wavelength sound waves allow one to determine the nonlinear scattered sound waves enable one to detect tiny changes of the contact network configuration at the grain

Paris 7 - Denis Diderot, Université

74

Gravity Waves Gravity Waves  

E-Print Network [OSTI]

;14/03/2014 6 H L H L L Phase & Group Velocity #12;14/03/2014 7 Doppler Effect #12;14/03/2014 8 Shock Waves #12;14/03/2014 14 Supernova Remnant Cassiopeia A Supernova blast waves #12;14/03/2014 15 Tycho's Remnant (SN 1572AD A SNR flythrough Theory of Supernova Blast Waves Supernovae: Type Ia Subsonic deflagration wave turning

Weijgaert, Rien van de

75

Calculations of Nonlinear Wave-Packet Interferometry Signals in the Pump-Probe Limit as Tests for Vibrational Control over Electronic Excitation Transfer  

E-Print Network [OSTI]

The preceding paper describes a strategy for externally influencing the course of short-time electronic excitation transfer (EET) in molecular dimers and observing the process by nonlinear wave-packet interferometry (nl-WPI). Within a sample of isotropically oriented dimers having a specified internal geometry, a vibrational mode internal to the acceptor chromophore can be preferentially driven by electronically nonresonant impulsive stimulated Raman (or resonant infrared) excitation with a short polarized control pulse. A subsequent electronically resonant polarized pump then preferentially excites the donor, and EET ensues. Here we test both the control strategy and its spectroscopic investigation-with some sacrifice of amplitude-level detail-by calculating the pump-probe difference signal. That signal is the limiting case of the control-influenced nl-WPI signal in which the two pulses in the pump pulse-pair coincide, as do the two pulses in the probe pulse-pair. We present calculated pump-probe difference signals for (1) a model excitation-transfer complex in which two equal-energy monomers each support one moderately Franck-Condon active intramolecular vibration; (2) a simplified model of the covalent dimer dithia-anthracenophane, representing its EET dynamics following selective impulsive excitation of the weakly Franck-Condon active anthracene vibration at 385 cm-1; and (3) a model complex featuring moderate electronic-vibrational coupling in which the site energy of the acceptor chromophore is lower than that of the donor.

Jason D. Biggs; Jeffrey A. Cina

2009-10-12T23:59:59.000Z

76

Waves  

E-Print Network [OSTI]

Waves is the supporting document to the Master of Fine Arts thesis exhibition of the same title. Exhibited March 7-12 2010 in the Art and Design Gallery at the University of Kansas, Waves was comprised of a series of mixed media drawings...

LaCure, Mari Mae

2010-04-29T23:59:59.000Z

77

Rogue Wave Modes for the Long Wave-Short Wave Resonance Kwok Wing CHOW*(1)  

E-Print Network [OSTI]

1 Rogue Wave Modes for the Long Wave-Short Wave Resonance Model Kwok Wing CHOW*(1) , Hiu Ning CHAN.45.Yv; 47.35.Fg ABSTRACT The long wave-short wave resonance model arises physically when the phase velocity of a long wave matches the group velocity of a short wave. It is a system of nonlinear evolution

78

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA. Volume II P-Wave Measurements in Borehole C4996 Seismic Records, Wave-Arrival Identifications and Interpreted P-Wave Velocity Profile.  

SciTech Connect (OSTI)

In this volume (II), all P-wave measurements are presented that were performed in Borehole C4996 at the Waste Treatment Plant (WTP) with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver. P-wave measurements were performed over the depth range of 360 to 1400 ft, typically in 10-ft intervals. However, in some interbeds, 5-ft depth intervals were used, while below about 1180 ft, depth intervals of 20 ft were used. Compression (P) waves were generated by moving the base plate of T-Rex for a given number of cycles at a fixed frequency as discussed in Section 2. This process was repeated so that signal averaging in the time domain was performed using 3 to about 15 averages, with 5 averages typically used. In addition to the LBNL 3-D geophone, called the lower receiver herein, a 3-D geophone from Redpath Geophysics was fixed at a depth of 22 ft in Borehole C4996, and a 3-D geophone from the University of Texas was embedded near the borehole at about 1.5 ft below the ground surface. This volume is organized into 12 sections as follows: Section 1: Introduction, Section 2: Explanation of Terminology, Section 3: Vp Profile at Borehole C4996, Sections 4 to 6: Unfiltered P-wave records of lower vertical receiver, reaction mass, and reference receiver, Sections 7 to 9: Filtered P-wave signals of lower vertical receiver, reaction mass and reference receiver, Section 10: Expanded and filtered P-wave signals of lower vertical receiver, and Sections 11 and 12: Waterfall plots of unfiltered and filtered lower vertical receiver signals.

Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh

2007-07-06T23:59:59.000Z

79

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA. Volume I P-Wave Measurements in Borehole C4993 Seismic Records, Wave-Arrival Identifications and Interpreted P-Wave Velocity Profile.  

SciTech Connect (OSTI)

In this volume (I), all P-wave measurements are presented that were performed in Borehole C4993 at the Waste Treatment Plant (WTP) with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver. P-wave measurements were performed over the depth range of 370 to 1400 ft, typically in 10-ft intervals. However, in some interbeds, 5-ft depth intervals were used, while below about 1200 ft, depth intervals of 20 ft were used. Compression (P) waves were generated by moving the base plate of T-Rex for a given number of cycles at a fixed frequency as discussed in Section 2. This process was repeated so that signal averaging in the time domain was performed using 3 to about 15 averages, with 5 averages typically used. In addition to the LBNL 3-D geophone, called the lower receiver herein, a 3-D geophone from Redpath Geophysics was fixed at a depth of 22 ft in Borehole C4993, and a 3-D geophone from the University of Texas was embedded near the borehole at about 1.5 ft below the ground surface. This volume is organized into 12 sections as follows: Section 1: Introduction, Section 2: Explanation of Terminology, Section 3: Vp Profile at Borehole C4993, Sections 4 to 6: Unfiltered P-wave records of lower vertical receiver, reaction mass, and reference receiver, Sections 7 to 9: Filtered P-wave signals of lower vertical receiver, reaction mass and reference receiver, Section 10: Expanded and filtered P-wave signals of lower vertical receiver, and Sections 11 and 12: Waterfall plots of unfiltered and filtered lower vertical receiver signals.

Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh

2007-07-06T23:59:59.000Z

80

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA. Volume III P-Wave Measurements in Borehole C4997 Seismic Records, Wave-Arrival Identifications and Interpreted P-Wave Velocity Profile.  

SciTech Connect (OSTI)

In this volume (III), all P-wave measurements are presented that were performed in Borehole C4997 at the Waste Treatment Plant (WTP) with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver. P-wave measurements were performed over the depth range of 390 to 1220 ft, typically in 10-ft intervals. However, in some interbeds, 5-ft depth intervals were used. Compression (P) waves were generated by moving the base plate of T-Rex for a given number of cycles at a fixed frequency as discussed in Section 2. This process was repeated so that signal averaging in the time domain was performed using 3 to about 15 averages, with 5 averages typically used. In addition to the LBNL 3-D geophone, called the lower receiver herein, a 3-D geophone from Redpath Geophysics was fixed at a depth of 40 ft (later relocated to 27.5 ft due to visibility in borehole after rain) in Borehole C4997, and a 3-D geophone from the University of Texas was embedded near the borehole at about 1.5 ft below the ground surface. This volume is organized into 12 sections as follows: Section 1: Introduction, Section 2: Explanation of Terminology, Section 3: Vp Profile at Borehole C4997, Sections 4 to 6: Unfiltered P-wave records of lower vertical receiver, reaction mass, and reference receiver, Sections 7 to 9: Filtered P-wave signals of lower vertical receiver, reaction mass and reference receiver, Section 10: Expanded and filtered P-wave signals of lower vertical receiver, and Sections 11 and 12: Waterfall plots of unfiltered and filtered lower vertical receiver signals.

Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh

2007-06-06T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" from the National Library of EnergyBeta (NLEBeta).
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81

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA. Volume IV S-Wave Measurements in Borehole C4993 Seismic Records, Wave-Arrival Identifications and Interpreted S-Wave Velocity Profile.  

SciTech Connect (OSTI)

In this volume (IV), all S-wave measurements are presented that were performed in Borehole C4993 at the Waste Treatment Plant (WTP) with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver. S-wave measurements were performed over the depth range of 370 to 1300 ft, typically in 10-ft intervals. However, in some interbeds, 5-ft depth intervals were used, while below about 1200 ft, depth intervals of 20 ft were used. Shear (S) waves were generated by moving the base plate of T-Rex for a given number of cycles at a fixed frequency as discussed in Section 2. This process was repeated so that signal averaging in the time domain was performed using 3 to about 15 averages, with 5 averages typically used. In addition, a second average shear wave record was recorded by reversing the polarity of the motion of the T-Rex base plate. In this sense, all the signals recorded in the field were averaged signals. In all cases, the base plate was moving perpendicular to a radial line between the base plate and the borehole which is in and out of the plane of the figure shown in Figure 1.1. The definition of “in-line”, “cross-line”, “forward”, and “reversed” directions in items 2 and 3 of Section 2 was based on the moving direction of the base plate. In addition to the LBNL 3-D geophone, called the lower receiver herein, a 3-D geophone from Redpath Geophysics was fixed at a depth of 22 ft in Borehole C4993, and a 3-D geophone from the University of Texas (UT) was embedded near the borehole at about 1.5 ft below the ground surface. The Redpath geophone and the UT geophone were properly aligned so that one of the horizontal components in each geophone was aligned with the direction of horizontal shaking of the T-Rex base plate. This volume is organized into 12 sections as follows. Section 1: Introduction, Section 2: Explanation of Terminology, Section 3: Vs Profile at Borehole C4993, Sections 4 to 6: Unfiltered S-wave records of lower horizontal receiver, reaction mass, and reference receiver, respectively, Sections 7 to 9: Filtered S-wave signals of lower horizontal receiver, reaction mass and reference receiver, respectively, Section 10: Expanded and filtered S-wave signals of lower horizontal receiver, and Sections 11 and 12: Waterfall plots of unfiltered and filtered lower horizontal receiver signals, respectively.

Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh

2007-06-06T23:59:59.000Z

82

High temperature probe  

DOE Patents [OSTI]

A high temperature probe for sampling, for example, smokestack fumes, and is able to withstand temperatures of 3000.degree. F. The probe is constructed so as to prevent leakage via the seal by placing the seal inside the water jacket whereby the seal is not exposed to high temperature, which destroys the seal. The sample inlet of the probe is also provided with cooling fins about the area of the seal to provide additional cooling to prevent the seal from being destroyed. Also, a heated jacket is provided for maintaining the temperature of the gas being tested as it passes through the probe. The probe includes pressure sensing means for determining the flow velocity of an efficient being sampled. In addition, thermocouples are located in various places on the probe to monitor the temperature of the gas passing there through.

Swan, Raymond A. (Fremont, CA)

1994-01-01T23:59:59.000Z

83

Nonlinear Pulse Propagation and Phase Velocity of Laser-Driven Plasma Waves C. B. Schroeder, C. Benedetti, E. Esarey, and W. P. Leemans  

E-Print Network [OSTI]

of high-quality GeV electron beams in centimeter-scale plasmas [2], the dynamics of the acceler- ated- ing length (distance for a relativistic particle to move out of an accelerating phase) and, hence=cm2 , or a0 * 1, to drive large ampli- tude plasma waves for particle acceleration. In the nonlinear

Geddes, Cameron Guy Robinson

84

Spectrophotometric probe  

DOE Patents [OSTI]

A support structure is described bearing at least one probe for making spectrophotometric measurements of a fluid using a source of light and a spectrophotometer. The probe includes a housing with two optical fibers and a planoconvex lens. A sleeve bearing a mirror surrounds the housing. The lens is separated from the mirror by a fixed distance, defining an interior space for receiving a volume of the fluid sample. A plurality of throughholes extending through the sleeve communicate between the sample volume and the exterior of the probe, all but one hole bearing a screen. A protective jacket surrounds the probe. A hollow conduit bearing a tube is formed in the wall of the probe for venting any air in the interior space when fluid enters. The probe is held at an acute angle so the optic fibers carrying the light to and from the probe are not bent severely on emergence from the probe. 3 figs.

Prather, W.S.; O'Rourke, P.E.

1994-08-02T23:59:59.000Z

85

WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA  

E-Print Network [OSTI]

case, the electrons have negative wave energy for 2w ne w wave energy for 2w .w > 0 nl Hence, unstable waves with negative phase velocity,

Cary, John R.

2012-01-01T23:59:59.000Z

86

Local tunneling characteristics near a grain boundary of a d-wave superconductor as probed by a normal-metal or a low-Tc-superconductor STM tip  

E-Print Network [OSTI]

We studied the local single-particle tunneling characteristics [as observed with scanning tunnel microscopy (STM)] for N D and S D tunneling, where N is a normal metal, S is a s-wave superconductor, and D is a d-wave superconductor with a {100...

Zhao, Hongwei

2005-08-29T23:59:59.000Z

87

Local Energy Velocity of Classical Fields  

E-Print Network [OSTI]

It is proposed to apply a recently developed concept of local wave velocities to the dynamical field characteristics, especially for the canonical field energy density. It is shown that local energy velocities can be derived from the lagrangian directly. The local velocities of zero- and first- order for energy propagation has been obtained for special cases of scalar and vector fields. Some important special cases of these results are discussed.

I. V. Drozdov; A. A. Stahlhofen

2007-04-19T23:59:59.000Z

88

A novel photonic Doppler velocimetry for transverse velocity measurement  

SciTech Connect (OSTI)

A fiber interferometry for transverse velocity measurement has been developed. This diagnostic is similar to photonic Doppler velocimetry in the way in which laser propagates and couples. The interferometer mainly consists of a fiber coupler, an emitting probe, and two receiving probes. A pair of scattered laser beams mix in the coupler and generates fringes with frequency proportional to transverse velocity. Measurement of transverse velocity is independent of longitudinal velocity. The feasibility of the technique has been verified by rotating wheel experiment and shock loading experiment.

Chen Guanghua; Wang Detian; Liu Jun; Meng Jianhua; Liu Shouxian; Yang Qingguo [Institute of Fluid Physics, CAEP, P.O. Box 919-109, Mianyang, Sichuan 621900 (China)

2013-01-15T23:59:59.000Z

89

Wave Mechanics and the Fifth Dimension  

E-Print Network [OSTI]

Replacing 4D Minkowski space by 5D canonical space leads to a clearer derivation of the main features of wave mechanics, including the wave function and the velocity of de Broglie waves. Recent tests of wave-particle duality could be adapted to investigate whether de Broglie waves are basically 4D or 5D in nature.

Paul S. Wesson; James M. Overduin

2013-01-28T23:59:59.000Z

90

IWA : an analysis program for isentropic wave measurements.  

SciTech Connect (OSTI)

IWA (Isentropic Wave Analysis) is a program for analyzing velocity profiles of isentropic compression experiments. IWA applies incremental impedance matching correction to measured velocity profiles to obtain in-situ particle velocity profiles for Lagrangian wave analysis. From the in-situ velocity profiles, material properties such as wave velocities, stress, strain, strain rate, and strength are calculated. The program can be run in any current version of MATLAB (2008a or later) or as a Windows XP executable.

Ao, Tommy

2009-02-01T23:59:59.000Z

91

Studies of the velocity fields near a submerged rectangular object  

E-Print Network [OSTI]

of the time periodic waves past a submerged rectangular object. For sotne wave conditions, large energy dissipation occurred at the submerged object due to vortex generation. The amount of energy dissipation was examined by comparing incident wave energy... object. A two component laser-Doppler anemometer (LDA) was used to obtain detailed measurements of the instantaneous velocity field and flow visualization was conducted to study the vortex structure around the submerged object. The measured wave...

Kim, Young-Ki

2012-06-07T23:59:59.000Z

92

PROPAGATING WAVES ALONG SPICULES  

SciTech Connect (OSTI)

Alfvenic waves are thought to play an important role in coronal heating and acceleration of solar wind. Here we investigate the statistical properties of Alfvenic waves along spicules (jets that protrude into the corona) in a polar coronal hole using high-cadence observations of the Solar Optical Telescope on board Hinode. We developed a technique for the automated detection of spicules and high-frequency waves. We detected 89 spicules and found (1) a mix of upward propagating, downward propagating, as well as standing waves (occurrence rates of 59%, 21%, and 20%, respectively); (2) the phase speed gradually increases with height; (3) upward waves dominant at lower altitudes, standing waves at higher altitudes; (4) standing waves dominant in the early and late phases of each spicule, while upward waves were dominant in the middle phase; (5) in some spicules, we find waves propagating upward (from the bottom) and downward (from the top) to form a standing wave in the middle of the spicule; and (6) the medians of the amplitude, period, and velocity amplitude were 55 km, 45 s, and 7.4 km s{sup -1}, respectively. We speculate that upward propagating waves are produced near the solar surface (below the spicule) and downward propagating waves are caused by reflection of (initially) upward propagating waves off the transition region at the spicule top. The mix of upward and downward propagating waves implies that exploiting these waves to perform seismology of the spicular environment requires careful analysis and may be problematic.

Okamoto, Takenori J. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); De Pontieu, Bart, E-mail: joten.okamoto@nao.ac.jp [Lockheed Martin Solar and Astrophysics Laboratory, B/252, 3251 Hanover Street, Palo Alto, CA 94304 (United States)

2011-08-01T23:59:59.000Z

93

Extreme wave impinging and overtopping  

E-Print Network [OSTI]

This investigates the velocity fields of a plunging breaking wave impinging on a structure through measurements in a two-dimensional wave tank. As the wave breaks and overtops the structure, so-called green water is generated. The flow becomes multi...

Ryu, Yong Uk

2009-06-02T23:59:59.000Z

94

Seismic Velocity And Attenuation Structure Of The Geysers Geothermal...  

Open Energy Info (EERE)

issue at this field is the distribution of fluid in the matrix of the reservoir rock. In this paper, we interpret seismic compressional-wave velocity and quality quotient...

95

The effect of rainfall on the velocity distribution in shallow channel flow  

E-Print Network [OSTI]

, gave the following equation for uniform two-dimensional open channel f low v v max ~2. Iog y Ve~~ in which v is the velocity at any distance, y, above the channel bed, v Is the maximum velocity, g is the acceleration of gravity, d is the Illa X... piezometer located at the same longi- tudinal position along the flume at the tip of the ve'locity probe. The velocity coefficient of the total head probe was obtained by two methods. 29 One method was determining the velocity by observing the time...

Glass, Larry Joe

1965-01-01T23:59:59.000Z

96

Autoresonant beat-wave generation R. R. Lindberg,a  

E-Print Network [OSTI]

means for the ponderomotive excitation of nonlinear Langmuir waves by phase-locking of the plasma wave to resonantly excite a large- amplitude, high-phase-velocity Langmuir wave suitable for particle acceleration p-1 E0, where p 1-vp 2 /c2 -1/2 . Here, vp is the phase-velocity of the excited plasma wave

Wurtele, Jonathan

97

Protective shield for an instrument probe  

DOE Patents [OSTI]

A shield is disclosed that is particularly useful for protecting exposed optical elements at the end of optical probes used in the analysis of hazardous emissions in and around an industrial environment from the contaminating effects of those emissions. The instant invention provides a hood or cowl in the shape of a right circular cylinder that can be fitted over the end of such optical probes. The hood provides a clear aperture through which the probe can perform unobstructed analysis. The probe optical elements are protected from the external environment by passing a dry gas through the interior of the hood and out through the hood aperture in sufficient quantity and velocity to prevent any significant mixing between the internal and external environments. Additionally, the hood is provided with a cooling jacket to lessen the potential for damaging the probe due to temperature excursions.

Johnsen, Howard A.; Ross, James R.; Birtola, Sal R.

2004-10-26T23:59:59.000Z

98

E-Print Network 3.0 - ambient transverse velocity Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the Radially Anisotropic Crustal Velocity Structure of NW Canada with Ambient-Noise Tomography M. E. Daigle1; C... -component records and Love waves on the transverse components....

99

Characterization of a Dipole Flow System Using Point Velocity Probes  

E-Print Network [OSTI]

of DFRTTs at the CFB Borden site, in Ontario, Canada, suggested that a homogeneous aquifer model was insufficient to replicate the experimental breakthrough curves. The DFRTT breakthrough data showed earlier arrival 6 times than expected from the model... holes drilled into the downgradient end of that container (Figures 1 and 2). Sand was contained within the second compartment by lining the irrigation fittings and the effluent end of the compartment with Nitex mesh. Because all the compartments...

Bowen, Ian Reed

2010-11-23T23:59:59.000Z

100

Directed Relativistic Blast Wave  

E-Print Network [OSTI]

A spherically symmetrical ultra-relativistic blast wave is not an attractor of a generic asymmetric explosion. Spherical symmetry is reached only by the time the blast wave slows down to non-relativistic velocities, when the Sedov-Taylor-von Neumann attractor solution sets in. We show however, that a directed relativistic explosion, with the explosion momentum close to the explosion energy, produces a blast wave with a universal intermediate asymptotic -- a selfsimilar directed ultra-relativistic blast wave. This universality might be of interest for the astrophysics of gamma-ray burst afterglows.

Andrei Gruzinov

2007-04-23T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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.


101

Projected Constraints on Lorentz-Violating Gravity with Gravitational Waves  

E-Print Network [OSTI]

Gravitational waves are excellent tools to probe the foundations of General Relativity in the strongly dynamical and non-linear regime. One such foundation is Lorentz symmetry, which can be broken in the gravitational sector by the existence of a preferred time direction, and thus, a preferred frame at each spacetime point. This leads to a modification in the orbital decay rate of binary systems, and also in the generation and chirping of their associated gravitational waves. We here study whether waves emitted in the late, quasi-circular inspiral of non-spinning, neutron star binaries can place competitive constraints on two proxies of gravitational Lorentz-violation: Einstein-\\AE{}ther theory and khronometric gravity. We model the waves in the small-coupling (or decoupling) limit and in the post-Newtonian approximation, by perturbatively solving the field equations in small deformations from General Relativity and in the small-velocity/weak-gravity approximation. We assume a gravitational wave consistent with General Relativity has been detected with second- and third-generation, ground-based detectors, and with the proposed space-based mission, DECIGO, with and without coincident electromagnetic counterparts. Without a counterpart, a detection consistent with General Relativity of neutron star binaries can only place competitive constraints on gravitational Lorentz violation when using future, third-generation or space-based instruments. On the other hand, a single counterpart is enough to place constraints that are 10 orders of magnitude more stringent than current binary pulsar bounds, even when using second-generation detectors. This is because Lorentz violation forces the group velocity of gravitational waves to be different from that of light, and this difference can be very accurately constrained with coincident observations.

Devin Hansen; Nicolas Yunes; Kent Yagi

2014-12-12T23:59:59.000Z

102

Traveling-wave photodetector  

DOE Patents [OSTI]

The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size. 4 figures.

Hietala, V.M.; Vawter, G.A.

1993-12-14T23:59:59.000Z

103

Traveling-wave photodetector  

SciTech Connect (OSTI)

The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size.

Hietala, V.M.; Vawter, G.A.

1992-12-31T23:59:59.000Z

104

Simultaneous use of camera and probe diagnostics to unambiguously identify and study the dynamics of multiple underlying instabilities during the route to plasma turbulence  

SciTech Connect (OSTI)

We use multiple-tip Langmuir probes and fast imaging to unambiguously identify and study the dynamics of underlying instabilities during the controlled route to fully-developed plasma turbulence in a linear magnetized helicon plasma device. Langmuir probes measure radial profiles of electron temperature, plasma density and potential; from which we compute linear growth rates of instabilities, cross-phase between density and potential fluctuations, Reynold's stress, particle flux, vorticity, time-delay estimated velocity, etc. Fast imaging complements the 1D probe measurements by providing temporally and spatially resolved 2D details of plasma structures associated with the instabilities. We find that three radially separated plasma instabilities exist simultaneously. Density gradient driven resistive drift waves propagating in the electron diamagnetic drift direction separate the plasma into an edge region dominated by strong, velocity shear driven Kelvin-Helmholtz instabilities and a central core region which shows coherent Rayleigh-Taylor modes propagating in the ion diamagnetic drift direction. The simultaneous, complementary use of both probes and camera was crucial to identify the instabilities and understand the details of the very rich plasma dynamics.

Thakur, S. C., E-mail: saikat@ucsd.edu; Tynan, G. R. [Center for Momentum Transport and Flow Organization, San Diego, California 92093 (United States); Center for Energy Research, University of California at San Diego, San Diego, California 92093 (United States); Brandt, C.; Cui, L.; Gosselin, J. J. [Center for Energy Research, University of California at San Diego, San Diego, California 92093 (United States); Light, A. [Center for Integrated Plasma Studies, Department of Physics, University of Colorado at Boulder, Boulder, Colorado 80309-0390 (United States)

2014-11-15T23:59:59.000Z

105

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, lossless, non-conducting, anisotropic uniform medium; (b) the definition is not consistent with the principle of relativity for a plane wave in a moving isotropic uniform medium. 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

2015-01-19T23:59:59.000Z

106

Development of a measurement system able to determine the ow velocity eld on models of hydraulic turbines  

E-Print Network [OSTI]

. Antoine Bombenger Probing strategy in a Kaplan Turbine Such a probe typically has a spherical head with 5 turbines Christian Landry Motivations & Objectives The project was driven by the need to improve the measurement of velocity elds and pressures in a hydraulic turbine. The development of a new probing system

Diggavi, Suhas

107

Monitoring attosecond dynamics of coherent electron-nuclear wave packets by molecular high-order-harmonic generation  

SciTech Connect (OSTI)

A pump-probe scheme for preparing and monitoring electron-nuclear motion in a dissociative coherent electron-nuclear wave packet is explored from numerical solutions of a non-Born-Oppenheimer time-dependent Schroedinger equation. A mid-ir intense few-cycle probe pulse is used to generate molecular high-order-harmonic generation (MHOHG) from a coherent superposition of two or more dissociative coherent electronic-nuclear wave packets, prepared by a femtosecond uv pump pulse. Varying the time delay between the intense ir probe pulse and the uv pump pulse by a few hundreds of attoseconds, the MHOHG signal intensity is shown to vary by orders of magnitude, thus showing the high sensitivity to electron-nuclear dynamics in coherent electron-nuclear wave packets. We relate this high sensitivity of MHOHG spectra to opposing electron velocities (fluxes) in the electron wave packets of the recombining (recolliding) ionized electron and of the bound electron in the initial coherent superposition of two electronic states.

Bredtmann, Timm [Laboratoire de Chimie Theorique, Faculte des Sciences, Universite de Sherbrooke, Sherbrooke, Quebec, J1K 2R1 (Canada); Institut fuer Chemie und Biochemie, Freie Universitaet Berlin, Takustrasse 3, D-14195 Berlin (Germany); Chelkowski, Szczepan; Bandrauk, Andre D. [Laboratoire de Chimie Theorique, Faculte des Sciences, Universite de Sherbrooke, Sherbrooke, Quebec, J1K 2R1 (Canada)

2011-08-15T23:59:59.000Z

108

Hydrodynamic ultrasonic probe  

DOE Patents [OSTI]

An improved probe for in-service ultrasonic inspection of long lengths of a workpiece, such as small diameter tubing from the interior. The improved probe utilizes a conventional transducer or transducers configured to inspect the tubing for flaws and/or wall thickness variations. The probe utilizes a hydraulic technique, in place of the conventional mechanical guides or bushings, which allows the probe to move rectilinearly or rotationally while preventing cocking thereof in the tube and provides damping vibration of the probe. The probe thus has lower friction and higher inspection speed than presently known probes.

Day, Robert A. (Livermore, CA); Conti, Armond E. (San Jose, CA)

1980-01-01T23:59:59.000Z

109

High-frequency Probing Diagnostic for Hall Current Plasma Thrusters  

SciTech Connect (OSTI)

High-frequency oscillations (1-100 MHz) in Hall thrusters have apparently eluded significant experimental scrutiny. A diagnostic setup, consisting of a single Langmuir probe, a special shielded probe connector-positioner, and an electronic impedance-matching circuit, was successfully built and calibrated. Through simultaneous high-frequency probing of the Hall thruster plasma at multiple locations, high-frequency plasma waves have been identified and characterized for various thruster operating conditions.

A.A. Litvak; Y. Raitses; N.J. Fisch

2001-10-25T23:59:59.000Z

110

Developing de Broglie Wave  

E-Print Network [OSTI]

The electromagnetic component waves, comprising together with their generating oscillatory massless charge a material particle, will be Doppler shifted when the charge hence particle is in motion, with a velocity $v$, as a mere mechanical consequence of the source motion. We illustrate here that two such component waves generated in opposite directions and propagating at speed $c$ between walls in a one-dimensional box, superpose into a traveling beat wave of wavelength ${\\mit\\Lambda}_d$$=(\\frac{v}{c}){\\mit\\Lambda}$ and phase velocity $c^2/v+v$ which resembles directly L. de Broglie's hypothetic phase wave. This phase wave in terms of transporting the particle mass at the speed $v$ and angular frequency ${\\mit\\Omega}_d=2\\pi v /{\\mit\\Lambda}_d$, with ${\\mit\\Lambda}_d$ and ${\\mit\\Omega}_d$ obeying the de Broglie relations, represents a de Broglie wave. The standing-wave function of the de Broglie (phase) wave and its variables for particle dynamics in small geometries are equivalent to the eigen-state solutions to Schr\\"odinger equation of an identical system.

J X Zheng-Johansson; P-I Johansson

2006-08-27T23:59:59.000Z

111

Explosive plane-wave lens  

DOE Patents [OSTI]

An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.

Marsh, S.P.

1987-03-12T23:59:59.000Z

112

Explosive plane-wave lens  

DOE Patents [OSTI]

An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.

Marsh, S.P.

1988-03-08T23:59:59.000Z

113

Time-resolved particle velocity measurements at impact velocities of 10 km/s  

SciTech Connect (OSTI)

Hypervelocity launch capabilities (9--16 km/s) with macroscopic plates have become available in recent years. It is now feasible to conduct instrumented plane-wave tests using this capability. Successfully conducting such tests requires a planar launch and impact at hypervelocities, appropriate triggering for recording systems, and time-resolved measurements of motion or stress at a particular point or set of points within the target or projectile during impact. The authors have conducted the first time-resolved wave-profile experiments using velocity interferometric techniques at impact velocities of 10 km/s. These measurements show that aluminum continues to exhibit normal release behavior to 161 GPa shock pressure, with complete loss of strength of the shocked state. These experiments have allowed a determination of shock-wave window transparency in conditions produced by a hypervelocity impact. In particular, lithium fluoride appears to lose transparency at a shock stress of 200 GPa; this appears to be the upper limit for conventional wave profile measurements using velocity interferometric techniques.

Furnish, M.D.; Chhabildas, L.C.; Reinhart, W.D.

1998-08-01T23:59:59.000Z

114

Velocity pump reaction turbine  

DOE Patents [OSTI]

An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

House, Palmer A. (Walnut Creek, CA)

1982-01-01T23:59:59.000Z

115

Velocity pump reaction turbine  

DOE Patents [OSTI]

An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

House, Palmer A. (Walnut Creek, CA)

1984-01-01T23:59:59.000Z

116

Are "EIT Waves" Fast-Mode MHD Waves?  

E-Print Network [OSTI]

We examine the nature of large-scale, coronal, propagating wave fronts (``EIT waves'') and find they are incongruous with solutions using fast-mode MHD plane-wave theory. Specifically, we consider the following properties: non-dispersive single pulse manifestions, observed velocities below the local Alfven speed, and different pulses which travel at any number of constant velocities, rather than at the ``predicted'' fast-mode speed. We discuss the possibility of a soliton-like explanation for these phenomena, and show how it is consistent with the above-mentioned aspects.

M. J. Wills-Davey; C. E. DeForest; J. O. Stenflo

2007-04-23T23:59:59.000Z

117

Visualizing the kinematics of relativistic wave packets  

E-Print Network [OSTI]

This article investigates some solutions of the time-dependent free Dirac equation. Visualizations of these solutions immediately reveal strange phenomena that are caused by the interference of positive- and negative-energy waves. The effects discussed here include the Zitterbewegung, the opposite direction of momentum and velocity in negative-energy wave packets, and the superluminal propagation of the wave packet's local maxima.

Bernd Thaller

2004-09-14T23:59:59.000Z

118

Shock waves in strongly coupled plasmas  

SciTech Connect (OSTI)

Shock waves are supersonic disturbances propagating in a fluid and giving rise to dissipation and drag. Weak shocks, i.e., those of small amplitude, can be well described within the hydrodynamic approximation. On the other hand, strong shocks are discontinuous within hydrodynamics and therefore probe the microscopics of the theory. In this paper, we consider the case of the strongly coupled N=4 plasma whose microscopic description, applicable for scales smaller than the inverse temperature, is given in terms of gravity in an asymptotically AdS{sub 5} space. In the gravity approximation, weak and strong shocks should be described by smooth metrics with no discontinuities. For weak shocks, we find the dual metric in a derivative expansion, and for strong shocks we use linearized gravity to find the exponential tail that determines the width of the shock. In particular, we find that, when the velocity of the fluid relative to the shock approaches the speed of light v{yields}1 the penetration depth l scales as l{approx}(1-v{sup 2}){sup 1/4}. We compare the results with second-order hydrodynamics and the Israel-Stewart approximation. Although they all agree in the hydrodynamic regime of weak shocks, we show that there is not even qualitative agreement for strong shocks. For the gravity side, the existence of shock waves implies that there are disturbances of constant shape propagating on the horizon of the dual black holes.

Khlebnikov, Sergei; Kruczenski, Martin; Michalogiorgakis, Georgios [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, Indiana 47907 (United States)

2010-12-15T23:59:59.000Z

119

New wave generation  

E-Print Network [OSTI]

We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (2007). This mechanism, which involves a tunable source comprised of oscillating plates, has so far been used for a few fundamental studies of internal waves, but its full potential has yet to be realized. Our studies reveal that this approach is capable of producing a wide variety of two-dimensional wave fields, including plane waves, wave beams and discrete vertical modes in finite-depth stratifications. The effects of discretization by a finite number of plates, forcing amplitude and angle of propagation are investigated, and it is found that the method is remarkably efficient at generating a complete wave field despite forcing only one velocity component in a controllable manner. We furthermore find that the nature of the radiated wave field is well predicted using Fourier transforms of the spatial structure of the wave generator.

Mercier, Matthieu J; Mathur, Manikandan; Gostiaux, Louis; Peacock, Thomas; Dauxois, Thierry

2015-01-01T23:59:59.000Z

120

SPECTROSCOPIC OBSERVATIONS OF A CORONAL MORETON WAVE  

SciTech Connect (OSTI)

We observed a coronal wave (EIT wave) on 2011 February 16, using EUV imaging data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) and EUV spectral data from the Hinode/EUV Imaging Spectrometer (EIS). The wave accompanied an M1.6 flare that produced a surge and a coronal mass ejection (CME). EIS data of the wave show a prominent redshifted signature indicating line-of-sight velocities of {approx}20 km s{sup -1} or greater. Following the main redshifted wave front, there is a low-velocity period (and perhaps slightly blueshifted), followed by a second redshift somewhat weaker than the first; this progression may be due to oscillations of the EUV atmosphere set in motion by the initial wave front, although alternative explanations may be possible. Along the direction of the EIS slit the wave front's velocity was {approx}500 km s{sup -1}, consistent with its apparent propagation velocity projected against the solar disk as measured in the AIA images, and the second redshifted feature had propagation velocities between {approx}200 and 500 km s{sup -1}. These findings are consistent with the observed wave being generated by the outgoing CME, as in the scenario for the classic Moreton wave. This type of detailed spectral study of coronal waves has hitherto been a challenge, but is now possible due to the availability of concurrent AIA and EIS data.

Harra, Louise K. [UCL-Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Sterling, Alphonse C. [Space Science Office, VP62, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Goemoery, Peter [Astronomical Institute, Slovak Academy of Sciences, SK-05960 Tatranska Lomnica (Slovakia); Veronig, Astrid, E-mail: lkh@mssl.ucl.ac.uk, E-mail: alphonse.sterling@nasa.gov, E-mail: gomory@astro.s, E-mail: astrid.veronig@uni-graz.at [Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria)

2011-08-10T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Slow waves in fractures filled with viscous fluid Valeri Korneev1  

E-Print Network [OSTI]

Slow waves in fractures filled with viscous fluid Valeri Korneev1 ABSTRACT Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves; therefore, their properties, a simple dispersion equa- tion for wave-propagation velocity is obtained. This velocity is much smaller

Korneev, Valeri A.

122

SURFACE ALFVEN WAVES IN SOLAR FLUX TUBES  

SciTech Connect (OSTI)

Magnetohydrodynamic (MHD) waves are ubiquitous in the solar atmosphere. Alfven waves and magneto-sonic waves are particular classes of MHD waves. These wave modes are clearly different and have pure properties in uniform plasmas of infinite extent only. Due to plasma non-uniformity, MHD waves have mixed properties and cannot be classified as pure Alfven or magneto-sonic waves. However, vorticity is a quantity unequivocally related to Alfven waves as compression is for magneto-sonic waves. Here, we investigate MHD waves superimposed on a one-dimensional non-uniform straight cylinder with constant magnetic field. For a piecewise constant density profile, we find that the fundamental radial modes of the non-axisymmetric waves have the same properties as surface Alfven waves at a true discontinuity in density. Contrary to the classic Alfven waves in a uniform plasma of infinite extent, vorticity is zero everywhere except at the cylinder boundary. If the discontinuity in density is replaced with a continuous variation of density, vorticity is spread out over the whole interval with non-uniform density. The fundamental radial modes of the non-axisymmetric waves do not need compression to exist unlike the radial overtones. In thin magnetic cylinders, the fundamental radial modes of the non-axisymmetric waves with phase velocities between the internal and the external Alfven velocities can be considered as surface Alfven waves. On the contrary, the radial overtones can be related to fast-like magneto-sonic modes.

Goossens, M.; Andries, J.; Soler, R.; Van Doorsselaere, T. [Centre for Plasma Astrophysics, Department of Mathematics, Katholieke Universiteit Leuven, Celestijnenlaan 200B, 3001 Leuven (Belgium); Arregui, I.; Terradas, J., E-mail: marcel.goossens@wis.kuleuven.be [Solar Physics Group, Departament de Fisica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)

2012-07-10T23:59:59.000Z

123

Ultrafast scanning probe microscopy  

DOE Patents [OSTI]

An ultrafast scanning probe microscopy method for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample.

Weiss, Shimon (El Cerrito, CA); Chemla, Daniel S. (Kensington, CA); Ogletree, D. Frank (El Cerrito, CA); Botkin, David (San Francisco, CA)

1995-01-01T23:59:59.000Z

124

Ultrafast scanning probe microscopy  

DOE Patents [OSTI]

An ultrafast scanning probe microscopy method is described for achieving subpicosecond-temporal resolution and submicron-spatial resolution of an observation sample. In one embodiment of the present claimed invention, a single short optical pulse is generated and is split into first and second pulses. One of the pulses is delayed using variable time delay means. The first pulse is then directed at an observation sample located proximate to the probe of a scanning probe microscope. The scanning probe microscope produces probe-sample signals indicative of the response of the probe to characteristics of the sample. The second pulse is used to modulate the probe of the scanning probe microscope. The time delay between the first and second pulses is then varied. The probe-sample response signal is recorded at each of the various time delays created between the first and second pulses. The probe-sample response signal is then plotted as a function of time delay to produce a cross-correlation of the probe sample response. In so doing, the present invention provides simultaneous subpicosecond-temporal resolution and submicron-spatial resolution of the sample. 6 Figs.

Weiss, S.; Chemla, D.S.; Ogletree, D.F.; Botkin, D.

1995-05-16T23:59:59.000Z

125

Discrimination of porosity and fluid saturation using seismic velocity analysis  

DOE Patents [OSTI]

The method of the invention is employed for determining the state of saturation in a subterranean formation using only seismic velocity measurements (e.g., shear and compressional wave velocity data). Seismic velocity data collected from a region of the formation of like solid material properties can provide relatively accurate partial saturation data derived from a well-defined triangle plotted in a (.rho./.mu., .lambda./.mu.)-plane. When the seismic velocity data are collected over a large region of a formation having both like and unlike materials, the method first distinguishes the like materials by initially plotting the seismic velocity data in a (.rho./.lambda., .mu./.lambda.)-plane to determine regions of the formation having like solid material properties and porosity.

Berryman, James G. (Danville, CA)

2001-01-01T23:59:59.000Z

126

Nonlinear three-wave interaction in marine sediments  

E-Print Network [OSTI]

Nonlinear interaction of three acoustic waves in a sandy sediment is studied in the frequency range where there is a considerable wave velocity dispersion. The possibility of an experimental observation of the generation of a sound wave by two pump waves propagating at an angle to each other is estimated.

N. I. Pushkina

2015-03-18T23:59:59.000Z

127

Collective behavior of stabilized reaction-diffusion waves  

SciTech Connect (OSTI)

Stabilized wave segments in the photosensitive Belousov-Zhabotinsky reaction are directionally controlled with intensity gradients in the applied illumination. The constant-velocity waves behave like self-propelled particles, and multiple waves interact via an applied interaction potential. Alignment arises from the intrinsic properties of the interacting waves, leading to processional and rotational behavior.

Steele, Aaron J.; Tinsley, Mark; Showalter, Kenneth [Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506-6045 (United States)

2008-06-15T23:59:59.000Z

128

Velocity centroids as tracers of the turbulent velocity statistics  

E-Print Network [OSTI]

We use the results of magnetohydrodynamic (MHD) simulations to emulate spectroscopic observations and use maps of centroids to study their statistics. In order to assess under which circumstances the scaling properties of the velocity field can be retrieved from velocity centroids, we compare two point statistics (structure functions and power-spectra) of velocity centroids with those of the underlying velocity field and analytic predictions presented in a previous paper (Lazarian & Esquivel 2003). We tested a criterion for recovering velocity spectral index from velocity centroids derived in our previous work, and propose an approximation of the early criterion using only the variances of ``unnormalized'' velocity centroids and column density maps. It was found that both criteria are necessary, however not sufficient to determine if the centroids recover velocity statistics. Both criteria are well fulfilled for subsonic turbulence. We find that for supersonic turbulence with sonic Mach numbers > 2.5 centroids fail to trace the spectral index of velocity. Asymptotically, however, we claim that recovery of velocity statistics is always possible provided that the density spectrum is steep and the observed inertial range is sufficiently extended. In addition, we show that velocity centroids are useful for anisotropy studies and determining the direction of magnetic field, even if the turbulence is highly supersonic, but only if it is sub-Alfvenic. This provides a tool for mapping the magnetic field direction, and testing whether the turbulence is sub-Alfvenic or super-Alfvenic.

A. Esquivel; A. Lazarian

2005-05-28T23:59:59.000Z

129

Statistics of Velocity from Spectral Data: Modified Velocity Centroids  

E-Print Network [OSTI]

We address the problem of studying interstellar turbulence using spectral line data. We find a criterion when the velocity centroids may provide trustworthy velocity statistics. To enhance the scope of centroids applications, we construct a measure that we term ``modified velocity centroids'' (MVCs) and derive an analytical solution that relates the 2D spectra of the modified centroids with the underlying 3D velocity spectrum. We test our results using synthetic maps constructed with data obtained through simulations of compressible magnetohydrodynamical (MHD) turbulence. We show that the modified velocity centroids (MVCs) are complementary to the the Velocity Channel Analysis (VCA) technique. Employed together, they make determining of the velocity spectral index more reliable and for wider variety of astrophysical situations.

A. Lazarian; A. Esquivel

2003-06-10T23:59:59.000Z

130

White light velocity interferometer  

DOE Patents [OSTI]

The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s.

Erskine, David J. (Oakland, CA)

1997-01-01T23:59:59.000Z

131

White light velocity interferometer  

DOE Patents [OSTI]

The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

Erskine, D.J.

1997-06-24T23:59:59.000Z

132

White light velocity interferometer  

DOE Patents [OSTI]

The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s.

Erskine, David J. (Oakland, CA)

1999-01-01T23:59:59.000Z

133

White light velocity interferometer  

DOE Patents [OSTI]

The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

Erskine, D.J.

1999-06-08T23:59:59.000Z

134

The Kinematic Wave Equation (KWE) In Tuesday's interrupted lecture we derived the Kinematic Wave Equation (KWE) for a density  

E-Print Network [OSTI]

The Kinematic Wave Equation (KWE) In Tuesday's interrupted lecture we derived the Kinematic Wave refer to partial derivatives. Kinematic waves occur when we take Q = Q(), in which case t + c()x = 0 (2) where the propagation velocity is c() = dQ/d. (2) is called the Kinematic Wave Equation (KWE). We wish

Gibbon, J. D.

135

Seismicity and Improved Velocity Structure in Kuwait  

SciTech Connect (OSTI)

The Kuwait National Seismic Network (KNSN) began operation in 1997 and consists of nine three-component stations (eight short-period and one broadband) and is operated by the Kuwait Institute for Scientific Research. Although the region is largely believed to be aseismic, considerable local seismicity is recorded by KNSN. Seismic events in Kuwait are clustered in two main groups, one in the south and another in the north. The KNSN station distribution is able to capture the southern cluster within the footprint of the network but the northern cluster is poorly covered. Events tend to occur at depths ranging from the free surface to about 20 km. Events in the northern cluster tend to be deeper than those in south, however this might be an artifact of the station coverage. We analyzed KNSN recordings of nearly 200 local events to improve understanding of seismic events and crustal structure in Kuwait, performing several analyses with increasing complexity. First, we obtained an optimized one-dimensional (1D) velocity model for the entire region using the reported KNSN arrival times and routine locations. The resulting model is consistent with a recently obtained model from the joint inversion of receiver functions and surface wave group velocities. Crustal structure is capped by the thick ({approx} 7 km) sedimentary rocks of the Arabian Platform underlain by normal velocities for stable continental crust. Our new model has a crustal thickness of 44 km, constrained by an independent study of receiver functions and surface wave group velocities by Pasyanos et al (2006). Locations and depths of events after relocation with the new model are broadly consistent with those reported by KISR, although a few events move more than a few kilometers. We then used a double-difference tomography technique (tomoDD) to jointly locate the events and estimate three-dimensional (3D) velocity structure. TomoDD is based on hypoDD relocation algorithm and it makes use of both absolute and relative arrival times. We obtained {approx}1500 absolute P and S arrival times and {approx}3200 P and S wave arrival time differences. Event locations do not change greatly when 3D velocity structure is included. Three-dimensional velocity structure, where resolvable, does not differ greatly from our optimized 1D model, indicating that the improved 1D model is adequate for routine event location. Finally, we calculated moment magnitudes, MW, for nearly 155 events using the coda magnitude technique of Mayeda et al., (2003). The fact that most of the relocated events occur below the known sedimentary structures extending to 7 km suggests that they are tectonic in origin. Shallow events within the sedimentary crust in the (southern) Minagish region may be related to oil field activities, although the current study cannot unambiguously determine the source of current seismicity in Kuwait. The improved velocity model reduces the scatter of travel time residuals relative to the locations reported in the KNSN bulletin and may be used for ground motion prediction and hazard estimate studies in Kuwait.

Gok, R M; Rodgers, A J; Al-Enezi, A

2006-01-26T23:59:59.000Z

136

Unitaxial constant velocity microactuator  

DOE Patents [OSTI]

A uniaxial drive system or microactuator capable of operating in an ultra-high vacuum environment is disclosed. The mechanism includes a flexible coupling having a bore therethrough, and two clamp/pusher assemblies mounted in axial ends of the coupling. The clamp/pusher assemblies are energized by voltage-operated piezoelectrics therewithin to operatively engage the shaft and coupling causing the shaft to move along its rotational axis through the bore. The microactuator is capable of repeatably positioning to sub-nanometer accuracy while affording a scan range in excess of 5 centimeters. Moreover, the microactuator generates smooth, constant velocity motion profiles while producing a drive thrust of greater than 10 pounds. The system is remotely controlled and piezoelectrically driven, hence minimal thermal loading, vibrational excitation, or outgassing is introduced to the operating environment. 10 figs.

McIntyre, T.J.

1994-06-07T23:59:59.000Z

137

A Reconsideration of Matter Waves  

E-Print Network [OSTI]

Matter waves were discovered in the early 20th century from their wavelength, predicted by DeBroglie, Planck's constant divided by the particle's momentum, that is, lmw = h/mv. But, the failure to obtain a reasonable theory for the matter wave frequency resulted somewhat in loss of further interest. It was expected that the frequency of the matter wave should correspond to the particle kinetic energy, that is, fmw = 1/2mv^2/h but the resulting velocity of the matter of the particle, v = fmw x lmw, is that the matter wave moves at one half the speed of the particle, obviously absurd as the particle and its wave must move together. If relativistic mass is used (as it should in any case) the problem remains, the same mass appearing in numerator and denominator and canceling. It is no help to hypothesize that the total energy, not just the kinetic energy, yields the matter wave. That attributes a matter wave to a particle at rest. It also gives the resulting velocity as c^2/v, the wave racing ahead of its particle. A reinterpretation of Einstein's derivation of relativistic kinetic energy (which produced his famous E = mc^2) leads to a valid matter wave frequency and a new understanding of particle kinetics and of the atom's stable orbits.

Roger Ellman

2005-05-16T23:59:59.000Z

138

Local tunneling characteristics near a grain boundary of a d-wave superconductor as probed by a normal-metal or a low-T-c-superconductor STM tip  

E-Print Network [OSTI]

We study the local single-particle tunneling characteristics [as observed with scanning tunnel microscopy (STM)] for N-D and S-D tunneling, where D is a d-wave superconductor with a {100}{110} grain boundary. The tunneling Hamiltonian method is used...

Zhao, HW; Hu, Chia-Ren.

2000-01-01T23:59:59.000Z

139

Propagation of gravitational waves in the nonperturbative spinor vacuum  

E-Print Network [OSTI]

The propagation of gravitational waves on the background of a nonperturbative vacuum of a spinor field is considered. It is shown that there are several distinctive features in comparison with the propagation of plane gravitational waves through empty space: there exists the fixed phase difference between the $h_{yy,zz}$ and $h_{yz}$ components of the wave; the phase and group velocities of gravitational waves are not equal to the velocity of light; the group velocity is always less than the velocity of light; under some conditions the gravitational waves are either damped or absent; for given frequency, there exist two waves with different wave vectors. We also discuss the possibility of experimental verification of the obtained effects as a tool to investigate nonperurbative quantum field theories.

Vladimir Dzhunushaliev; Vladimir Folomeev

2014-09-02T23:59:59.000Z

140

Backreacting p-wave Superconductors  

E-Print Network [OSTI]

We study the gravitational backreaction of the non-abelian gauge field on the gravity dual to a 2+1 p-wave superconductor. We observe that as in the $p+ip$ system a second order phase transition exists between a superconducting and a normal state. Moreover, we conclude that, below the phase transition temperature $T_c$ the lowest free energy is achieved by the p-wave solution. In order to probe the solution, we compute the holographic entanglement entropy. For both $p$ and $p+ip$ systems the entanglement entropy satisfies an area law. For any given entangling surface, the p-wave superconductor has lower entanglement entropy.

Raúl E. Arias; Ignacio Salazar Landea

2013-01-28T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Ponderomotive Forces On Waves In Modulated Media  

SciTech Connect (OSTI)

Nonlinear interactions of waves via instantaneous cross-phase modulation can be cast in the same way as ponderomotive wave-particle interactions in high-frequency electromagnetic fi eld. The ponderomotive effect arises when rays of a probe wave scatter off perturbations of the underlying medium produced by a second, modulation wave, much like charged particles scatter off a quasiperiodic field. Parallels with the point-particle dynamics, which itself is generalized by this theory, lead to new methods of wave manipulation, including asymmetric barriers for light.

Dodin, I.Y; Fisch, Nathaniel

2014-02-28T23:59:59.000Z

142

Alfv'en Wave Solitons and Solar Intermediate Drift Bursts  

E-Print Network [OSTI]

propagate at velocities of the order of the Alfv'en veloc­ ity in a direction inclined to the magnetic field, the solar wind, and possibly accretion disks, and extra­ galactic jets. In such magnetized plasmas Alfv'en waves are easily excited by various processes. Linear waves propagate at the Alfv'en speed v

Guedel, Manuel

143

Measurement of turbulent wind velocities using a rotating boom apparatus  

SciTech Connect (OSTI)

The present report covers both the development of a rotating-boom facility and the evaluation of the spectral energy of the turbulence measured relative to the rotating boom. The rotating boom is composed of a helicopter blade driven through a pulley speed reducer by a variable speed motor. The boom is mounted on a semiportable tower that can be raised to provide various ratios of hub height to rotor diameter. The boom can be mounted to rotate in either the vertical or horizontal plane. Probes that measure the three components of turbulence can be mounted at any location along the radius of the boom. Special hot-film sensors measured two components of the turbulence at a point directly in front of the rotating blade. By using the probe rotated 90/sup 0/ about its axis, the third turbulent velocity component was measured. Evaluation of the spectral energy distributions for the three components of velocity indicates a large concentration of energy at the rotational frequency. At frequencies slightly below the rotational frequency, the spectral energy is greatly reduced over that measured for the nonrotating case measurements. Peaks in the energy at frequencies that are multiples of the rotation frequency were also observed. We conclude that the rotating boom apparatus is suitable and ready to be used in experiments for developing and testing sensors for rotational measurement of wind velocity from wind turbine rotors. It also can be used to accurately measure turbulent wind for testing theories of rotationally sampled wind velocity.

Sandborn, V.A.; Connell, J.R.

1984-04-01T23:59:59.000Z

144

Comparison of P-wave and S-wave data in a fractured reservoir  

E-Print Network [OSTI]

communication, 1993) Figure 8 A closeup map of the elevation on the Base Austin Chalk in the study area. Map compiled by A. Davidoff (personal communication, 1993). . . . . . . . . . . . . 12 Figure 9 Flow chart of conventional data pxocessing procedures... INTRODUCTION In recent years, researchers have combined P-wave and S-wave seismic data to study subsurface lithology and porosity. Experimental studies have shown that the velocity ratio of the P waves and S waves (VPIVs) decreases about 10% to 20% when gas...

Al-Mustafa, Husam Mustafa

2012-06-07T23:59:59.000Z

145

Electrochemical Waves on Patterned Surfaces: Propagation through Narrow Gaps and Konstantin Agladze, Stephanie Thouvenel-Romans, and Oliver Steinbock*  

E-Print Network [OSTI]

Electrochemical Waves on Patterned Surfaces: Propagation through Narrow Gaps and Channels propagation through narrow gaps and long channels. In channels, the wave velocity decreases with decreasing dynamically similar phenomena such as propagating fronts, target patterns, and rotating spiral waves. Pattern

Steinbock, Oliver

146

Measurement of fast-changing low velocities by photonic Doppler velocimetry  

SciTech Connect (OSTI)

Despite the increasing popularity of photonic Doppler velocimetry (PDV) in shock wave experiments, its capability of capturing low particle velocities while changing rapidly is still questionable. The paper discusses the performance of short time Fourier transform (STFT) and continuous wavelet transform (CWT) in processing fringe signals of fast-changing low velocities measured by PDV. Two typical experiments are carried out to evaluate the performance. In the laser shock peening test, the CWT gives a better interpretation to the free surface velocity history, where the elastic precursor, main plastic wave, and elastic release wave can be clearly identified. The velocities of stress waves, Hugoniot elastic limit, and the amplitude of shock pressure induced by laser can be obtained from the measurement. In the Kolsky-bar based tests, both methods show validity of processing the longitudinal velocity signal of incident bar, whereas CWT improperly interprets the radial velocity of the shocked sample at the beginning period, indicating the sensitiveness of the CWT to the background noise. STFT is relatively robust in extracting waveforms of low signal-to-noise ratio. Data processing method greatly affects the temporal resolution and velocity resolution of a given fringe signal, usually CWT demonstrates a better local temporal resolution and velocity resolution, due to its adaptability to the local frequency, also due to the finer time-frequency product according to the uncertainty principle.

Song Hongwei; Wu Xianqian; Huang Chenguang; Wei Yangpeng; Wang Xi [Key Laboratory for Hydrodynamics and Ocean Engineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China)

2012-07-15T23:59:59.000Z

147

Sound velocities of ferropericlase in the Earth's lower mantle Jung-Fu Lin,1  

E-Print Network [OSTI]

. Introduction [2] The speed of seismic waves in the Earth's lower mantle is governed by the elastic properties a dramatic increase in the isothermal bulk modulus (KT) and bulk sound velocity (VF) at the electronic spinSound velocities of ferropericlase in the Earth's lower mantle Jung-Fu Lin,1 Steven D. Jacobsen,2

Lin, Jung-Fu "Afu"

148

Converted wave imaging in anisotropic media using sea-floor seismic data   

E-Print Network [OSTI]

velocity ratio is derived conventionally by event matching in the P-wave and converted wave stacks. I present an attempt to use well-log derived velocity ratios to avoid this interpretative step. The velocity ratio derived from 4C seismic data is about 30...

Mancini, Fabio

149

Mach reflection of spherical detonation waves  

SciTech Connect (OSTI)

When two detonation waves collide, the shape of the wave front at their intersection can be used to categorize the flow as regular or irregular reflection. In the case of regular reflection, the intersection of the waves forms a cusp. In the case of irregular reflection, the cusp is replaced by a leading shock locus that bridges the incident waves. Many workers have studied irregular or Mach reflection of detonation waves, but most of the their experimental work has focused on the interaction of plane detonation waves. Reflection of spherical detonation waves has received less attention. This study also differs from previous work in that the focus is to measure the relationship between the detonation velocity and the local wave curvatue for irregular reflection of spherical detonation waves. Two explosives with different detonation properties, PBX 9501 and PBX 9502, are compared.

Hull, L.M.

1993-07-01T23:59:59.000Z

150

Kinematics measurements of regular, irregular, and rogue waves by PIV/LDV  

E-Print Network [OSTI]

waves. A series of experiments were conducted in a 2-D wave tank at Texas A&M University to measure wave velocities and accelerations using LDV and PIV systems. The wave crests of regular and rogue waves are the focus of this study. With the measured...

Choi, Hae-Jin

2007-04-25T23:59:59.000Z

151

Liu UCD Phy9B 07 1 Ch15. Mechanical Waves  

E-Print Network [OSTI]

Liu UCD Phy9B 07 1 Ch15. Mechanical Waves #12;Liu UCD Phy9B 07 2 15-1. Introduction Source: disturbance + cohesive force between adjacent pieces A wave is a disturbance that propagates through space Mechanical wave: needs a medium to propagate Wave pulse #12;Liu UCD Phy9B 07 3 Distinctions Wave velocity vs

Yoo, S. J. Ben

152

Wave propagation in a seven-story reinforced concrete building I. Theoretical modelsq  

E-Print Network [OSTI]

Wave propagation in a seven-story reinforced concrete building I. Theoretical modelsq M natural to use wave propagation methods. In this paper (Part I), we review several two-dimensional wave/s and bx/bz 1 for EW vibrations. The velocity of shear waves propagating through the slabs is estimated

Southern California, University of

153

Carbon nanotube based electromechanical probes  

E-Print Network [OSTI]

Electromechanical probing applications continuously require smaller pitches, faster manufacturing and lower electrical resistance. Conventional techniques, such as MEMS based cantilever probes have their shortcomings in ...

Yaglioglu, Onnik, 1976-

2007-01-01T23:59:59.000Z

154

Laser induced fluorescence measurements of ion velocity and temperature of drift turbulence driven sheared plasma flow in a linear helicon plasma device  

SciTech Connect (OSTI)

Using laser induced fluorescence (LIF), radial profiles of azimuthal ion fluid velocity and ion temperature are measured in the controlled shear de-correlation experiment (CSDX) linear helicon plasma device. Ion velocities and temperatures are derived from the measured Doppler broadened velocity distribution functions of argon ions. The LIF system employs a portable, high power (>300 mW), narrowband ({approx}1 MHz) tunable diode laser-based system operating at 668.614 nm. Previous studies in CSDX have shown the existence of a radially sheared azimuthal flow as measured with time delay estimation methods and Mach probes. Here, we report the first LIF measurements of sheared plasma fluid flow in CSDX. Above a critical magnetic field, the ion fluid flow profile evolves from radially uniform to peaked on axis with a distinct reversed flow region at the boundary, indicating the development of a sheared azimuthal flow. Simultaneously, the ion temperature also evolves from a radially uniform profile to a profile with a gradient. Measurements in turbulent and coherent drift wave mode dominated plasmas are compared.

Chakraborty Thakur, S.; Fedorczak, N.; Manz, P.; Tynan, G. R.; Xu, M. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); Center for Energy Research, University of California at San Diego, San Diego, California 92093 (United States); McCarren, D.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Lee, T. [Center for Energy Research, University of California at San Diego, San Diego, California 92093 (United States)

2012-08-15T23:59:59.000Z

155

Foldable polymers as probes  

DOE Patents [OSTI]

Disclosed herein are novel probes, which can be used to detect and identify target molecules of interest in a sample. The disclosed probes can be used to monitor conformational changes induced by molecular recognition events in addition to providing signaling the presence and/or identity of a target molecule. Methods, including solid phase synthesis techniques, for making probe molecules that exhibit changes in their optical properties upon target molecule binding are described in the disclosure. Also disclosed herein are novel chromophore moieties, which have tailored fluorescent emission spectra.

Li, Alexander D. Q. (Pullman, WA); Wang, Wei (Pullman, WA)

2009-07-07T23:59:59.000Z

156

Chemical sensing flow probe  

SciTech Connect (OSTI)

A new chemical probe determines the properties of an analyte using the light absorption of the products of a reagent/analyte reaction. The probe places a small reaction volume in contact with a large analyte volume. Analyte diffuses into the reaction volume. Reagent is selectively supplied to the reaction volume. The light absorption of the reaction in the reaction volume indicates properties of the original analyte. The probe is suitable for repeated use in remote or hostile environments. It does not require physical sampling of the analyte or result in significant regent contamination of the analyte reservoir. 7 figs.

Laguna, G.R.; Peter, F.J.; Butler, M.A.

1999-02-16T23:59:59.000Z

157

Probing metal solidification nondestructively  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar Home DesignPresentationsSRS Responds toPrivacyProbingProbingProbing

158

Chemical sensing flow probe  

DOE Patents [OSTI]

A new chemical probe determines the properties of an analyte using the light absorption of the products of a reagent/analyte reaction. The probe places a small reaction volume in contact with a large analyte volume. Analyte diffuses into the reaction volume. Reagent is selectively supplied to the reaction volume. The light absorption of the reaction in the reaction volume indicates properties of the original analyte. The probe is suitable for repeated use in remote or hostile environments. It does not require physical sampling of the analyte or result in significant regent contamination of the analyte reservoir.

Laguna, George R. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Butler, Michael A. (Albuquerque, NM)

1999-01-01T23:59:59.000Z

159

Velocity-Space Diffusion in a Perpendicularly Propagating Electrostatic Wave  

E-Print Network [OSTI]

-@ax(k_~y-wt) in con- midered. When o)Qi and ul 2w/kL, the e q u a t hofmotion may be reduced to r net of dillerence in Fig. 1. Expanding the trajectory about the raumance point, we find that the magnitude of the impulses

Karney, Charles

160

Longshore sediment transport rate calculated incorporating wave orbital velocity fluctuations  

E-Print Network [OSTI]

Laboratory experiments were performed to study and improve longshore sediment transport rate predictions. Measured total longshore transport in the laboratory was approximately three times greater for plunging breakers than spilling breakers. Three...

Smith, Ernest Ray

2006-10-30T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen  

E-Print Network [OSTI]

Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen Genetic Adaptive­surface models from seismic travel­time data. Given a sub­surface model, the physics of wave propagation through refractive media can be used to compute travel times for seismic waves. How­ ever, in practice, we have

Louis, Sushil J.

162

Fermi velocity renormalization and dynamical gap generation in graphene  

E-Print Network [OSTI]

We study the renormalization of the Fermi velocity by the long-range Coulomb interactions between the charge carriers in the Dirac-cone approximation for the effective low-energy description of the electronic excitations in graphene at half filling. Solving the coupled system of Dyson-Schwinger equations for the dressing functions in the corresponding fermion propagator with various approximations for the particle-hole polarization we observe that Fermi velocity renormalization effects generally lead to a considerable increase of the critical coupling for dynamical gap generation and charge-density wave formation at the semimetal-insulator transition.

C. Popovici; C. S. Fischer; L. von Smekal

2015-01-12T23:59:59.000Z

163

The various manifestations of collisionless dissipation in wave propagation  

SciTech Connect (OSTI)

The propagation of an electrostatic wave packet inside a collisionless and initially Maxwellian plasma is always dissipative because of the irreversible acceleration of the electrons by the wave. Then, in the linear regime, the wave packet is Landau damped, so that in the reference frame moving at the group velocity, the wave amplitude decays exponentially with time. In the nonlinear regime, once phase mixing has occurred and when the electron motion is nearly adiabatic, the damping rate is strongly reduced compared to the Landau one, so that the wave amplitude remains nearly constant along the characteristics. Yet, we show here that the electrons are still globally accelerated by the wave packet, and in one dimension, this leads to a non local amplitude dependence of the group velocity. As a result, a freely propagating wave packet would shrink, and therefore, so would its total energy. In more than one dimension, not only does the magnitude of the group velocity nonlinearly vary, but also its direction. In the weakly nonlinear regime, when the collisionless damping rate is still significant compared to its linear value, the group velocity is directed towards the outside of the wave packet and tends to increase its transverse extent, while the opposite is true once the wave is essentially undamped. The impact of the nonlinear variation of the group velocity on the transverse size of the wave packet is quantified, and compared to that induced by the self-focussing due to wave front bowing.

Benisti, Didier; Morice, Olivier; Gremillet, Laurent [CEA, DAM, DIF, F-91297 Arpajon (France)

2012-06-15T23:59:59.000Z

164

Variables and units in Ocean 420 u zonal velocity (east-west) m/s  

E-Print Network [OSTI]

speed m/s Cg group velocity m/s k wave number 1/m frequency 1/s wavelength m T period s kinematic mixed-layer and water below C E Energy density in surface gravity wave J/m 2 #12;Some constants k Von surface height m g gravitational constant m/s 2 a amplitude of wave in sea surface height m f Coriolis

Thompson, LuAnne

165

New insights on boundary plasma turbulence and the quasi-coherent mode in Alcator C-Mod using a Mirror Langmuir Probe  

SciTech Connect (OSTI)

A new “Mirror Langmuir Probe” diagnostic, combined with a double-coil scanning magnetic probe, is used to interrogate Alcator C-Mod's quasi-coherent mode (QCM) with unprecedented detail. In ohmic EDA H-modes, the QCM is found to reside in a region of positive radial electric field, with a radial width (?3?mm) that spans open and closed field line regions. Large amplitude, in-phase sinusoidal bursts (?100?kHz) in density, electron temperature, and plasma potential are observed, with potential lagging density by ?16°, producing an outward radial transport velocity of ?10?m/s. Mode propagation corresponds to the sum of local E × B and electron diamagnetic drift velocities. Poloidal magnetic field fluctuations project to current filaments carrying peak current densities of ?25 A/cm{sup 2}. An evaluation of parallel electron force balance (Ohm's law) over a fluctuation cycle indicates a significant electromotive component. Interchange drive is also a contributor in the current continuity (vorticity) equation. Thus, the QCM is primarily a separatrix-spanning electron drift-wave with interchange and electromagnetic contributions.

LaBombard, B.; Golfinopoulos, T.; Terry, J. L.; Brunner, D.; Davis, E.; Greenwald, M.; Hughes, J. W. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)] [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)

2014-05-15T23:59:59.000Z

166

Trapping and Frequency Variability in Electron Acoustic Waves  

E-Print Network [OSTI]

Trapping and Frequency Variability in Electron Acoustic Waves C.F. Driscoll, F. Anderegg, D 92093 USA Abstract. Electron Acoustic Waves (EAWs) with a phase velocity less than twice the plasma Langmuir waves, and at large excitations resonance is observed over a broad range. Laser Induced

California at San Diego, University of

167

GMTI radar minimum detectable velocity.  

SciTech Connect (OSTI)

Minimum detectable velocity (MDV) is a fundamental consideration for the design, implementation, and exploitation of ground moving-target indication (GMTI) radar imaging modes. All single-phase-center air-to-ground radars are characterized by an MDV, or a minimum radial velocity below which motion of a discrete nonstationary target is indistinguishable from the relative motion between the platform and the ground. Targets with radial velocities less than MDV are typically overwhelmed by endoclutter ground returns, and are thus not generally detectable. Targets with radial velocities greater than MDV typically produce distinct returns falling outside of the endoclutter ground returns, and are thus generally discernible using straightforward detection algorithms. This document provides a straightforward derivation of MDV for an air-to-ground single-phase-center GMTI radar operating in an arbitrary geometry.

Richards, John Alfred

2011-04-01T23:59:59.000Z

168

Convective heat flow probe  

DOE Patents [OSTI]

A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

Dunn, J.C.; Hardee, H.C.; Striker, R.P.

1984-01-09T23:59:59.000Z

169

Simultaneous wave and current forces on a cylinder near the bottom boundary  

E-Print Network [OSTI]

- ing Program and Professor R. O. Raid for their review of this thesis. Special thanks are due to Mrs. Lori Baldwin, Mr. and Mrs. Ron Watanabe and Mr, Kenneth Kim for their co-operation in the preparation of the manuscript. TABLE OF CONTENTS Chapter... Potential of Combined Wave and Current = Velocity Potential of Wave = Velocity Potential of Current Surface Density Spectrum = Velocity Density Spectrum Acceleration Density Spectrum p Density of Fluid v ~ Kinematic Viscosity &o Wave Prequency &uq...

Knoll, David Alex

1979-01-01T23:59:59.000Z

170

Techniques for improving the readout sensitivity of gravitational wave antennae  

E-Print Network [OSTI]

The detection of gravitational waves (GWs) from astrophysical sources shows promise as a new method to probe extremely energetic phenomena and test the strong field limit of the general theory of relativity. The era of the ...

Smith-Lefebvre, Nicolás de Mateo

2012-01-01T23:59:59.000Z

171

Multispectral imaging probe  

DOE Patents [OSTI]

A multispectral imaging probe delivers a range of wavelengths of excitation light to a target and collects a range of expressed light wavelengths. The multispectral imaging probe is adapted for mobile use and use in confined spaces, and is sealed against the effects of hostile environments. The multispectral imaging probe comprises a housing that defines a sealed volume that is substantially sealed from the surrounding environment. A beam splitting device mounts within the sealed volume. Excitation light is directed to the beam splitting device, which directs the excitation light to a target. Expressed light from the target reaches the beam splitting device along a path coaxial with the path traveled by the excitation light from the beam splitting device to the target. The beam splitting device directs expressed light to a collection subsystem for delivery to a detector.

Sandison, David R. (Moriarty, NM); Platzbecker, Mark R. (Albuquerque, NM); Descour, Michael R. (Tucson, AZ); Armour, David L. (Albuquerque, NM); Craig, Marcus J. (Albuquerque, NM); Richards-Kortum, Rebecca (Austin, TX)

1999-01-01T23:59:59.000Z

172

Multispectral imaging probe  

DOE Patents [OSTI]

A multispectral imaging probe delivers a range of wavelengths of excitation light to a target and collects a range of expressed light wavelengths. The multispectral imaging probe is adapted for mobile use and use in confined spaces, and is sealed against the effects of hostile environments. The multispectral imaging probe comprises a housing that defines a sealed volume that is substantially sealed from the surrounding environment. A beam splitting device mounts within the sealed volume. Excitation light is directed to the beam splitting device, which directs the excitation light to a target. Expressed light from the target reaches the beam splitting device along a path coaxial with the path traveled by the excitation light from the beam splitting device to the target. The beam splitting device directs expressed light to a collection subsystem for delivery to a detector. 8 figs.

Sandison, D.R.; Platzbecker, M.R.; Descour, M.R.; Armour, D.L.; Craig, M.J.; Richards-Kortum, R.

1999-07-27T23:59:59.000Z

173

Probing Mercury's Partnering Preferences  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar Home DesignPresentationsSRS Responds toPrivacy ActProbingProbing

174

Probing metal solidification nondestructively  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16 FORPoints ofProbing Strain-Induced ChangesProbing

175

Atom Probe Tomography | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone byDear Friend,Arthur J. NozikAtom Probe Tomography Atom Probe

176

E-Print Network 3.0 - augmented wave method Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

turbulent velocities The method to calculate wave energy fluxes carried by longitudinal tube... frequency points n. Another computational parameter, which affects our method of...

177

Ultrasonic guided waves in eccentric annular pipes  

SciTech Connect (OSTI)

This paper studies the feasibility of using ultrasonic guided waves to rapidly inspect tubes and pipes for possible eccentricity. While guided waves are well established in the long range inspection of structures such as pipes and plates, studies for more complex cross sections are limited and analytical solutions are often difficult to obtain. Recent developments have made the Semi Analytical Finite Element (SAFE) method widely accessible for researchers to study guided wave properties in complex structures. Here the SAFE method is used to study the effect of eccentricity on the modal structures and velocities of lower order guided wave modes in thin pipes of diameters typically of interest to the industry. Results are validated using experiments. The paper demonstrates that even a small eccentricity in the pipe can strongly affect guided wave mode structures and velocities and hence shows potential for pipe eccentricity inspection.

Pattanayak, Roson Kumar; Balasubramaniam, Krishnan; Rajagopal, Prabhu [Centre for NDE, Indian Institute of Technology - Madras Chennai 600036, T. N. (India)

2014-02-18T23:59:59.000Z

178

An upper bound from helioseismology on the stochastic background of gravitational waves  

E-Print Network [OSTI]

The universe is expected to be permeated by a stochastic background of gravitational radiation of astrophysical and cosmological origin. This background is capable of exciting oscillations in solar-like stars. Here we show that solar-like oscillators can be employed as giant hydrodynamical detectors for such a background in the muHz to mHz frequency range, which has remained essentially unexplored until today. We demonstrate this approach by using high-precision radial velocity data for the Sun to constrain the normalized energy density of the stochastic gravitational-wave background around 0.11 mHz. These results open up the possibility for asteroseismic missions like CoRoT and Kepler to probe fundamental physics.

Daniel M. Siegel; Markus Roth

2014-03-28T23:59:59.000Z

179

Quantitative imaging of the air-water flow fields formed by unsteady breaking waves  

E-Print Network [OSTI]

An experimental method for simultaneously measuring the velocity fields on the air and water side of unsteady breaking waves is presented. The method is applied to breaking waves to investigate the physics of the air and ...

Belden, Jesse (Jesse Levi)

2009-01-01T23:59:59.000Z

180

Dynamics of excitation pulses with attractive interaction: Kinematic analysis and chemical wave experiments  

E-Print Network [OSTI]

Dynamics of excitation pulses with attractive interaction: Kinematic analysis and chemical wave present a theoretical analysis of stacking and destacking wave trains in excitable reaction-diffusion systems with anomalous velocity-wavelength dependence. For linearized dispersion relations, kinematic

Steinbock, Oliver

Note: This page contains sample records for the topic "velocity wave probe" 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

Velocity requirements for causality violation  

E-Print Network [OSTI]

We re-examine the "Regge-Tolman paradox" with reference to some recent experimental results. It is straightforward to find a formula for the velocity v of the moving system required to produce causality violation. This formula typically yields a velocity very close to the speed of light (for instance, v/c > 0.97 for X-shaped microwaves), which raises some doubts about the real physical observability of the violations. We then compute the velocity requirement introducing a delay between the reception of the primary signal and the emission of the secondary. It turns out that in principle for any delay it is possible to find moving observers able to produce active causal violation. This is mathematically due to the singularity of the Lorentz transformations for beta to 1. For a realistic delay due to the propagation of a luminal precursor, we find that causality violations in the reported experiments are still more unlikely (v/c > 0.989), and even in the hypothesis that the superluminal propagation velocity goes to infinity, the velocity requirement is bounded by v/c > 0.62. We also prove that if two macroscopic bodies exchange energy and momentum through superluminal signals, then the swap of signal source and target is incompatible with the Lorentz transformations; therefore it is not possible to distinguish between source and target, even with reference to a definite reference frame.

Giovanni Modanese

2015-01-18T23:59:59.000Z

182

Measuring OutdoorAir Intake Rates Using Electronic Velocity Sensors at Louvers and Downstream of Airflow Straighteners  

SciTech Connect (OSTI)

Practical and accurate technologies are needed for continuously measuring and controlling outdoor air (OA) intake rates in commercial building heating, ventilating, and air conditioning (HVAC) systems. This project evaluated two new measurement approaches. Laboratory experiments determined that OA flow rates were measurable with errors generally less than 10percent using electronic air velocity probes installed between OA intake louver blades or at the outlet face of louvers. High accuracy was maintained with OA flow rates as low as 15percent of the maximum for the louvers. Thus, with this measurement approach HVAC systems do not need separate OA intakes for minimum OA supply. System calibration parameters are required for each unique combination of louver type and velocity sensor location but calibrations are not necessary for each system installation. The research also determined that the accuracy of measuring OA flow rates with velocity probes located in the duct downstream of the intake louver was not improved by installing honeycomb airflow straighteners upstream of the probes. Errors varied with type of upstream louver, were as high as 100percent, and were often greater than 25percent. In conclusion, use of electronic air velocity probes between the blades of OA intake louvers or at the outlet face of louvers is a highly promising means of accurately measuring rates of OA flow into HVAC systems. The use of electronic velocity probes downstream of airflow straighteners is less promising, at least with the relatively small OA HVAC inlet systems employed in this research.

Fisk, William; Sullivan, Douglas; Cohen, Sebastian; Han, Hwataik

2008-10-01T23:59:59.000Z

183

Nonlinear Hysteretic Torsional Waves  

E-Print Network [OSTI]

We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities, and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other type of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short term memory as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.

J. Cabaret; P. Béquin; G. Theocharis; V. Andreev; V. E. Gusev; V. Tournat

2015-01-09T23:59:59.000Z

184

Nonlinear Hysteretic Torsional Waves  

E-Print Network [OSTI]

We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities, and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other type of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short term memory as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control de...

Cabaret, J; Theocharis, G; Andreev, V; Gusev, V E; Tournat, V

2015-01-01T23:59:59.000Z

185

Seismic velocity structure and microearthquake source properties at The Geysers, California, geothermal area  

SciTech Connect (OSTI)

The method of progressive hypocenter-velocity inversion has been extended to incorporate S-wave arrival time data and to estimate S-wave velocities in addition to P-wave velocities. S-wave data to progressive inversion does not completely eliminate hypocenter-velocity tradeoffs, but they are substantially reduced. Results of a P and S-wave progressive hypocenter-velocity inversion at The Geysers show that the top of the steam reservoir is clearly defined by a large decrease of V/sub p//V/sub s/ at the condensation zone-production zone contact. The depth interval of maximum steam production coincides with minimum observed V/sub p//V/sub s/, and V/sub p//V/sub s/ increses below the shallow primary production zone suggesting that reservoir rock becomes more fluid saturated. The moment tensor inversion method was applied to three microearthquakes at The Geysers. Estimated principal stress orientations were comparable to those estimated using P-wave firstmotions as constraints. Well constrained principal stress orientations were obtained for one event for which the 17 P-first motions could not distinguish between normal-slip and strike-slip mechanisms. The moment tensor estimates of principal stress orientations were obtained using far fewer stations than required for first-motion focal mechanism solutions. The three focal mechanisms obtained here support the hypothesis that focal mechanisms are a function of depth at The Geysers. Progressive inversion as developed here and the moment tensor inversion method provide a complete approach for determining earthquake locations, P and S-wave velocity structure, and earthquake source mechanisms.

O'Connell, D.R.

1986-12-01T23:59:59.000Z

186

Torsional waves propagation in an initially stressed dissipative cylinder  

E-Print Network [OSTI]

The present paper has been framed to show the effect of damping on the propagation of torsional waves in an initially stressed, dissipative, incompressible cylinder of infinite length. A governing equation has been formulated on Biot's incremental deformation theory. The velocities of torsional waves are obtained as complex ones, in which real part gives the phase velocity of propagation and corresponding imaginary part gives the damping. The study reveals that the damping of the medium has strong effect in the propagation of torsional wave. Since every medium has damping so it is more realistic to use the damped wave equation instead of the undamped wave equation. The study also shows that the velocity of propagation of such waves depend on the presence of initial stress. The influences of damping and initial stresses are shown separately.

M. M. Selim

2009-03-28T23:59:59.000Z

187

Lithospheric Velocity Structure of the Anatolain plateau-Caucasus-Caspian Regions  

SciTech Connect (OSTI)

Anatolian Plateau-Caucasus-Caspian region is an area of complex structure accompanied by large variations in seismic wave velocities. Despite the complexity of the region little is known about the detailed lithospheric structure. Using data from 29 new broadband seismic stations in the region, a unified velocity structure is developed using teleseismic receiver functions and surface waves. Love and Rayleigh surface waves dispersion curves have been derived from event-based analysis and ambient-noise correlation. We jointly inverted the receiver functions with the surface wave dispersion curves to determine absolute shear wave velocity and important discontinuities such as sedimentary layer, Moho, lithospheric-asthenospheric boundary. We combined these new station results with Eastern Turkey Seismic Experiment results (29 stations). Caspian Sea and Kura basin underlained by one of the thickest sediments in the world. Therefore, short-period surface waves are observed to be very slow. The strong crustal multiples in receiver functions and the slow velocities in upper crust indicate the presence of thick sedimentary unit (up to 20 km). Crustal thickness varies from 34 to 52 km in the region. The thickest crust is in Lesser Caucasus and the thinnest is in the Arabian Plate. The lithospheric mantle in the Greater Caucasus and the Kura depression is faster than the Anatolian Plateau and Lesser Caucasus. This possibly indicates the presence of cold lithosphere. The lower crust is slowest in the northeastern part of the Anatolian Plateau where Holocene volcanoes are located.

Gok, R; Mellors, R J; Sandvol, E; Pasyanos, M; Hauk, T; Yetirmishli, G; Teoman, U; Turkelli, N; Godoladze, T; Javakishvirli, Z

2009-04-15T23:59:59.000Z

188

Propagation of transverse zero sound in He3and of spin waves in He3-He II solutions  

E-Print Network [OSTI]

Propagation of transverse zero sound in He3and of spin waves in He3-He II solutions E. P. Bashkin absorption may dominate if the wave propagation velocity is close to the Fermi value. It is shown that the propagation of transverse zero sound in He3 is possible even if the wave velocity is somewhat smaller than

Meyerovich, Alex

189

APRIL 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves  

E-Print Network [OSTI]

APRIL 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves J. N. MOUM1 , J. M. KLYMAK2. The energy transported by these waves includes a nonlinear advection term uE that is negligible in linear internal waves. Unlike linear internal waves, the pressure-velocity energy flux up includes important

190

SEPTEMBER 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves  

E-Print Network [OSTI]

SEPTEMBER 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves J. N. MOUM1 , J. M of coastline. The energy transported by these waves includes a nonlinear advection term uE that is negligible in linear internal waves. Unlike linear internal waves, the pressure-velocity energy flux up includes

191

Velocity Distributions from Nonextensive Thermodynamics  

E-Print Network [OSTI]

There is no accepted mechanism that explains the equilibrium structures that form in collisionless cosmological N-body simulations. Recent work has identified nonextensive thermodynamics as an innovative approach to the problem. The distribution function that results from adopting this framework has the same form as for polytropes, but the polytropic index is now related to the degree of nonextensiveness. In particular, the nonextensive approach can mimic the equilibrium structure of dark matter density profiles found in simulations. We extend the investigation of this approach to the velocity structures expected from nonextensive thermodynamics. We find that the nonextensive and simulated N-body rms-velocity distributions do not match one another. The nonextensive rms-velocity profile is either monotonically decreasing or displays little radial variation, each of which disagrees with the rms-velocity distributions seen in simulations. We conclude that the currently discussed nonextensive models require further modifications in order to corroborate dark matter halo simulations. (adapted from TeX)

Eric I. Barnes; Liliya L. R. Williams; Arif Babul; Julianne J. Dalcanton

2006-10-05T23:59:59.000Z

192

Low-frequency fluid waves in fractures and pipes  

SciTech Connect (OSTI)

Low-frequency analytical solutions have been obtained for phase velocities of symmetrical fluid waves within both an infinite fracture and a pipe filled with a viscous fluid. Three different fluid wave regimes can exist in such objects, depending on the various combinations of parameters, such as fluid density, fluid viscosity, walls shear modulus, channel thickness, and frequency. Equations for velocities of all these regimes have explicit forms and are verified by comparisons with the exact solutions. The dominant role of fractures in rock permeability at field scales and the strong amplitude and frequency effects of Stoneley guided waves suggest the importance of including these wave effects into poroelastic theories.

Korneev, Valeri

2010-09-01T23:59:59.000Z

193

Dark Energy Probes of Dark Energy  

E-Print Network [OSTI]

19/12/2013 1 Dark Energy Probes of Dark Energy Probes Dark Energy Supernovae Ia probing luminosity (Betti numbers) #12;19/12/2013 2 Dark Energy Probes: Comparison Method Strengths Weaknesses Systematics

Weijgaert, Rien van de

194

Sonar probing of concrete  

E-Print Network [OSTI]

ABSTRACT Sonar Probing of Concrete (May 1988) John H. Mims, B. A. , Carleton College Chairman of Advisory Committee: Dr. Robert R, Unterberger Two systems were used for acoustical tests at concrete dams. The first system used a pair of donated... reflections from several concrete-air interfaces at the Norfork Dam, Arkansas. A reflection between two walls in the dam's operating gallery which were 6. 73 m apart was recorded at 3. 4 ms (peak value). After subtracting the appropriate delays, this value...

Mims, John Hornsby

1988-01-01T23:59:59.000Z

195

Site-Specific Velocity and Density Model for the Waste Treatment Plant, Hanford, Washington.  

SciTech Connect (OSTI)

This report documents the work conducted under the SBP to develop a shear wave and compressional wave velocity and density model specific to the WTP site. Section 2 provides detailed background information on the WTP site and its underlying geology as well as on the Seismic Boreholes Project activities leading up to the Vs and Vp measurements. In Section 3, methods employed and results obtained are documented for measurements of Vs and Vp velocities in basalts and interbeds. Section 4 provides details on velocity measurements in the sediments underlying the WTP. Borehole gravity measurements of density of the subsurface basalt and sediments are described in Section 5. Section 6 describes the analysis of data presented in section 3-5, and presents the overall velocity and density model for the WTP site.

Rohay, Alan C.; Brouns, Thomas M.

2007-06-27T23:59:59.000Z

196

Ring diagram analysis of velocity fields within the solar convection zone  

E-Print Network [OSTI]

Ring diagram analysis of solar oscillation power spectra obtained from MDI data is performed to study the velocity fields within the solar convection zone. The three dimensional power spectra are fitted to a model with a Lorentzian profile in frequency and includes the advection of the wave front by horizontal flows to obtain the two horizontal components of flows as a function of the horizontal wave number and radial order of the oscillation modes. This information is then inverted using the OLA and RLS techniques to infer the variation in flow velocity with depth. The resulting velocity fields yield the mean rotation velocity at different latitudes which agrees reasonably with helioseismic estimates. The zonal flow inferred in the outermost layers also appears to be in agreement with other measurements. A meridional flow from equator polewards is found to have an amplitude of about 25 m/s near the surface and the amplitude appears to increase with depth.

Sarbani Basu; H. M. Antia; S. C. Tripathy

1998-06-23T23:59:59.000Z

197

System and method for determining coolant level and flow velocity in a nuclear reactor  

DOE Patents [OSTI]

A boiling water reactor includes a reactor pressure vessel having a feedwater inlet for the introduction of recycled steam condensate and/or makeup coolant into the vessel, and a steam outlet for the discharge of produced steam for appropriate work. A fuel core is located within a lower area of the pressure vessel. The fuel core is surrounded by a core shroud spaced inward from the wall of the pressure vessel to provide an annular downcomer forming a coolant flow path between the vessel wall and the core shroud. A probe system that includes a combination of conductivity/resistivity probes and/or one or more time-domain reflectometer (TDR) probes is at least partially located within the downcomer. The probe system measures the coolant level and flow velocity within the downcomer.

Brisson, Bruce William; Morris, William Guy; Zheng, Danian; Monk, David James; Fang, Biao; Surman, Cheryl Margaret; Anderson, David Deloyd

2013-09-10T23:59:59.000Z

198

Vacuum Waves  

E-Print Network [OSTI]

As an example of the unification of gravitation and particle physics, an exact solution of the five-dimensional field equations is studied which describes waves in the classical Einstein vacuum. While the solution is essentially 5D in nature, the waves exist in ordinary 3D space, and may provide a way to test for an extra dimension.

Paul S. Wesson

2012-12-11T23:59:59.000Z

199

GEOPHYSICS, VOL. 65, NO. 1 (JANUARY-FEBRUARY 2000); P. 232246, 11 FIGS., 2 TABLES. Inversion of azimuthally dependent NMO velocity in transversely  

E-Print Network [OSTI]

) or crack systems. P-wave kinematic signatures in TTI media are controlled by the velocity VP0 kinematic signatures, can be found only from the moveout of shear waves. Using the exact NMO equation, we ) of the symmetry axis. Here, we show that all five parameters can be obtained from az- imuthally varying P-wave NMO

Tsvankin, Ilya

200

Nonlinear effects on interfacial wave growth into slug flow  

E-Print Network [OSTI]

It is known that when two fluids flow through a horizontal channel, depending on the relative velocity between the two fluids, two different instability mechanisms can create initial wave disturbances on the interface: the ...

Campbell, Bryce K

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

BENCAP, LLC: CAPSULE VELOCITY TEST  

SciTech Connect (OSTI)

Ben Cap, LLC, has a technology that utilizes bebtonite to plug wells. The bentonite is encapsulated in a cardboard capsule, droped down to the bottom of the well where it is allowed to hydrate, causing the bentonite to expand and plug the well. This method of plugging a well is accepted in some, but not all states. This technology can save a significant amount of money when compared to cementing methods currently used to plug and abandon wells. The test objective was to obtain the terminal velocity of the capsule delivery system as it drops through a column of water in a wellbore. Once the terminal velocity is known, the bentonite swelling action can be timed not to begin swelling until it reaches the bottom of the well bore. The results of the test showed that an average speed of 8.93 plus or minus 0.12 ft/sec was achieved by the capsule as it was falling through a column of water. Plotting the data revealed a very linear function with the capsules achieving terminal velocity shortly after being released. The interference of the capsule impacting the casing was not readily apparent in any of the runs, but a siginal sampling anomaly was present in one run. Because the anomaly was so brief and not present in any of the other runs, no solid conclusions could be drawn. Additional testing would be required to determine the effects of capsules impacting a fluid level that is not at surface.

Meidinger, Brian

2005-09-07T23:59:59.000Z

202

Wave-particle interaction and Hamiltonian dynamics investigated in a traveling wave tube  

SciTech Connect (OSTI)

For wave-particle interaction studies, the one-dimensional (1-D) beam-plasma system can be advantageously replaced by a Traveling Wave Tube (TWT). This led us to a detailed experimental analysis of the self-consistent interaction between unstable waves and a small either cold or warm beam. More recently, a test electron beam has been used to observe its non-self-consistent interaction with externally excited wave(s). The velocity distribution function of the electron beam is investigated with a trochoidal energy analyzer that records the beam energy distribution at the output of the TWT. An arbitrary waveform generator is used to launch a prescribed spectrum of waves along the slow wave structure (a 4 m long helix) of the TWT. The nonlinear synchronization of particles by a single wave responsible for Landau damping is observed. The resonant velocity domain associated to a single wave is also observed, as well as the transition to large-scale chaos when the resonant domains of two waves and their secondary resonances overlap leading to a typical 'devil's staircase' behavior. A new strategy for the control of chaos is tested.

Doveil, Fabrice; Macor, Alessandro [Physique des Interactions Ioniques et Moleculaires, Unite 6633 CNRS-Universite de Provence, Equipe Turbulence Plasma, Case 321, Centre de Saint-Jerome, F-13397 Marseille cedex 20 (France)

2006-05-15T23:59:59.000Z

203

Experimental probes of axions  

SciTech Connect (OSTI)

Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting familiar, coherent electromagnetic laboratory techniques, including resonant enhancement of transitions using microwave and optical cavities, Bragg scattering, and coherent photon-axion oscillations. The axion beam may either be astrophysical in origin as in the case of dark matter axion searches and solar axion searches, or created in the laboratory from laser interactions with magnetic fields. This note is meant to be a sampling of recent experimental results.

Chou, Aaron S.; /Fermilab

2009-10-01T23:59:59.000Z

204

Electromagnetic Probes in PHENIX  

E-Print Network [OSTI]

Electromagnetic probes are arguably the most universal tools to study the different physics processes in high energy hadron and heavy ion collisions. In this paper we summarize recent measurements of real and virtual direct photons at central rapidity by the PHENIX experiment at RHIC in p+p, d+Au and Au+Au collisions. We also discuss the impact of the results and the constraints they put on theoretical models. At the end we report on the immediate as well as on the mid-term future of photon measurements at RHIC.

Gabor David

2006-09-21T23:59:59.000Z

205

Compressional-wave and shear-wave velocities from long-spaced sonic waveforms  

E-Print Network [OSTI]

-SPACED SONIC TOOL UT LTF R L TNR 3' Lr TN R LrTFR LT 10' C FR NR 8' D I FRI (( 'I ll NrR ) ( rt I ll ))8. I ) 8 I I I I ) I I I l I I I-I Ii& I ? ? +) ? +l ?? I I~ I lk ) I LT I ? I I 10' A LT Figure 2. Configuration... REFERENCES 56 VITA 58 LIST OF TABLES TABLE Page I Input parameters for synthetic sonic waveforms. 23 2 Synthetic waveform computed slowness error ? 9"-diameter borehole. . . . 25 3 Synthetic waveform computed slowness error ? 4"-diameter borehole...

Lake, Leonard Cornelius

2012-06-07T23:59:59.000Z

206

Measuring In-Situ Mdf Velocity Of Detonation  

DOE Patents [OSTI]

A system for determining the velocity of detonation of a mild detonation fuse mounted on the surface of a device includes placing the device in a predetermined position with respect to an apparatus that carries a couple of sensors that sense the passage of a detonation wave at first and second spaced locations along the fuse. The sensors operate a timer and the time and distance between the locations is used to determine the velocity of detonation. The sensors are preferably electrical contacts that are held spaced from but close to the fuse such that expansion of the fuse caused by detonation causes the fuse to touch the contact, causing an electrical signal to actuate the timer.

Horine, Frank M. (Albuquerque, NM); James, Jr., Forrest B. (Albuquerque, NM)

2005-10-25T23:59:59.000Z

207

The critical velocity in the BEC-BCS crossover  

E-Print Network [OSTI]

We map out the critical velocity in the crossover from Bose-Einstein condensation (BEC) to Bardeen-Cooper-Schrieffer superfluidity with ultracold $^{6}$Li gases. A small attractive potential is dragged along lines of constant column density. The rate of the induced heating increases steeply above a critical velocity $v_c$. In the same samples, we measure the speed of sound $v_s$ by exciting density waves and compare the results to the measured values of $v_c$. We perform numerical simulations in the BEC regime and find very good agreement, validating the approach. In the strongly correlated regime, where theoretical predictions only exist for the speed of sound, our measurements of $v_c$ provide a testing ground for theoretical approaches.

Wolf Weimer; Kai Morgener; Vijay Pal Singh; Jonas Siegl; Klaus Hueck; Niclas Luick; Ludwig Mathey; Henning Moritz

2014-08-22T23:59:59.000Z

208

Method of accelerating photons by a relativistic plasma wave  

DOE Patents [OSTI]

Photons of a laser pulse have their group velocity accelerated in a plasma as they are placed on a downward density gradient of a plasma wave of which the phase velocity nearly matches the group velocity of the photons. This acceleration results in a frequency upshift. If the unperturbed plasma has a slight density gradient in the direction of propagation, the photon frequencies can be continuously upshifted to significantly greater values.

Dawson, John M. (Pacific Palisades, CA); Wilks, Scott C. (Santa Monica, CA)

1990-01-01T23:59:59.000Z

209

Bose-Einstein Condensates as a Probe for Lorentz Violation  

E-Print Network [OSTI]

The effects of small Lorentz-violating terms on Bose-Einstein condensates are analyzed. We find that there are changes to the phase and shape of the ground-state wave function that vary with the orientation of the trap. In addition, spin-couplings can act as a source for spontaneous symmetry breaking in ferromagnetic condensates making them sensitive probes for fundamental symmetry violation.

Don Colladay; Patrick McDonald

2006-02-08T23:59:59.000Z

210

Lagrangian kinematics of steep waves up to the inception of a spilling breaker  

E-Print Network [OSTI]

Horizontal Lagrangian velocities and accelerations at the surface of steep water-waves are studied by Particle Tracking Velocimetry (PTV) for gradually increasing crest heights up to the inception of a spilling breaker. Localized steep waves are excited using wavemaker-generated Peregrine breather-type wave trains. Actual crest and phase velocities are estimated from video recorded sequences of the instantaneous wave shape as well as from surface elevation measurements by wave gauges. Effects of nonlinearity and spectral width on phase velocity, as well as relation between the phase velocity and crest propagation speed are discussed. The inception of a spilling breaker is associated with the horizontal velocity of water particles at the crest attaining that of the crest, thus confirming the kinematic criterion for inception of breaking.

Shemer, Lev

2013-01-01T23:59:59.000Z

211

Probing Multiparton Correlations at CEBAF  

E-Print Network [OSTI]

In this talk, I explore the possibilities of probing the multiparton correlation functions at CEBAF at its current energy and the energies with its future upgrades.

Jianwei Qiu

1998-08-08T23:59:59.000Z

212

PRECISION RADIAL VELOCITIES WITH CSHELL  

SciTech Connect (OSTI)

Radial velocity (RV) identification of extrasolar planets has historically been dominated by optical surveys. Interest in expanding exoplanet searches to M dwarfs and young stars, however, has motivated a push to improve the precision of near-infrared RV techniques. We present our methodology for achieving 58 m s{sup -1} precision in the K band on the M0 dwarf GJ 281 using the CSHELL spectrograph at the 3 m NASA Infrared Telescope Facility. We also demonstrate our ability to recover the known 4 M{sub JUP} exoplanet Gl 86 b and discuss the implications for success in detecting planets around 1-3 Myr old T Tauri stars.

Crockett, Christopher J.; Prato, L. [Lowell Observatory, 1400 W Mars Hill Road, Flagstaff, AZ 86001 (United States); Mahmud, Naved I.; Johns-Krull, Christopher M. [Department of Physics and Astronomy, Rice University, MS-108, 6100 Main Street, Houston, TX 77005 (United States); Jaffe, Daniel T. [Department of Astronomy, University of Texas, R.L. Moore Hall, Austin, TX 78712 (United States); Beichman, Charles A., E-mail: crockett@lowell.edu, E-mail: lprato@lowell.edu, E-mail: naved@rice.edu, E-mail: cmj@rice.edu, E-mail: dtj@astro.as.utexas.edu [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

2011-07-10T23:59:59.000Z

213

Newberry EGS Seismic Velocity Model  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

We use ambient noise correlation (ANC) to create a detailed image of the subsurface seismic velocity at the Newberry EGS site down to 5 km. We collected continuous data for the 22 stations in the Newberry network, together with 12 additional stations from the nearby CC, UO and UW networks. The data were instrument corrected, whitened and converted to single bit traces before cross correlation according to the methodology in Benson (2007). There are 231 unique paths connecting the 22 stations of the Newberry network. The additional networks extended that to 402 unique paths crossing beneath the Newberry site.

Templeton, Dennise

214

Newberry EGS Seismic Velocity Model  

SciTech Connect (OSTI)

We use ambient noise correlation (ANC) to create a detailed image of the subsurface seismic velocity at the Newberry EGS site down to 5 km. We collected continuous data for the 22 stations in the Newberry network, together with 12 additional stations from the nearby CC, UO and UW networks. The data were instrument corrected, whitened and converted to single bit traces before cross correlation according to the methodology in Benson (2007). There are 231 unique paths connecting the 22 stations of the Newberry network. The additional networks extended that to 402 unique paths crossing beneath the Newberry site.

Templeton, Dennise

2013-10-01T23:59:59.000Z

215

TIGER: A data analysis pipeline for testing the strong-field dynamics of general relativity with gravitational wave signals from coalescing compact binaries  

E-Print Network [OSTI]

The direct detection of gravitational waves with upcoming second-generation gravitational wave observatories such as Advanced LIGO and Advanced Virgo will allow us to probe the genuinely strong-field dynamics of general ...

Agathos, M.

216

Investigation of Wave Energy Converter Effects on Near-shore Wave Fields: Model Generation Validation and Evaluation - Kaneohe Bay HI.  

SciTech Connect (OSTI)

The numerical model, SWAN (Simulating WAves Nearshore) , was used to simulate wave conditions in Kaneohe Bay, HI in order to determine the effects of wave energy converter ( WEC ) devices on the propagation of waves into shore. A nested SWAN model was validated then used to evaluate a range of initial wave conditions: significant wave heights (H s ) , peak periods (T p ) , and mean wave directions ( MWD) . Differences between wave height s in the presence and absence of WEC device s were assessed at locations in shore of the WEC array. The maximum decrease in wave height due to the WEC s was predicted to be approximately 6% at 5 m and 10 m water depths. Th is occurred for model initiation parameters of H s = 3 m (for 5 m water depth) or 4 m (10 m water depth) , T p = 10 s, and MWD = 330deg . Subsequently, bottom orbital velocities were found to decrease by about 6%.

Roberts, Jesse D.; Chang, Grace; Jones, Craig

2014-09-01T23:59:59.000Z

217

Wave represents displacement Wave represents pressure Source -Sound Waves  

E-Print Network [OSTI]

Wave represents displacement Wave represents pressure Source - Sound Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency Wave represents pressure Target - Radio Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency

Colorado at Boulder, University of

218

Slow Waves in Fractures Filled with Viscous Fluid  

SciTech Connect (OSTI)

Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type solution, in which fracture walls are assumed to be rigid. At seismic prospecting frequencies and realistic fracture thicknesses, the Stoneley guided wave has wavelengths on the order of several meters and an attenuation Q factor exceeding 10, which indicates the possibility of resonance excitation in fluid-bearing rocks. The velocity and attenuation of Stoneley guided waves are distinctly different at low frequencies for water and oil. The predominant role of fractures in fluid flow at field scales is supported by permeability data showing an increase of several orders of magnitude when compared to values obtained at laboratory scales. These data suggest that Stoneley guided waves should be taken into account in theories describing seismic wave propagation in fluid-saturated rocks.

Korneev, Valeri

2008-01-08T23:59:59.000Z

219

Heat transfer probe  

DOE Patents [OSTI]

Apparatuses, systems, methods, and computer code for, among other things, monitoring the health of samples such as the brain while providing local cooling or heating. A representative device is a heat transfer probe, which includes an inner channel, a tip, a concentric outer channel, a first temperature sensor, and a second temperature sensor. The inner channel is configured to transport working fluid from an inner inlet to an inner outlet. The tip is configured to receive at least a portion of the working fluid from the inner outlet. The concentric outer channel is configured to transport the working fluid from the inner outlet to an outer outlet. The first temperature sensor is coupled to the tip, and the second temperature sensor spaced apart from the first temperature sensor.

Frank, Jeffrey I.; Rosengart, Axel J.; Kasza, Ken; Yu, Wenhua; Chien, Tai-Hsin; Franklin, Jeff

2006-10-10T23:59:59.000Z

220

Nonlinear acoustic wave generation in a three-phase seabed  

E-Print Network [OSTI]

Generation of an acoustic wave by two pump sound waves is studied in a three-phase marine sediment that consists of a solid frame and the pore water with air bubbles in it. To avoid shock-wave formation the interaction is considered in the frequency range where there is a significant amount of sound velocity dispersion. Nonlinear equations are obtained to describe the interaction of acoustic waves in the presence of air bubbles. An expression for the amplitude of the generated wave is obtained and numerical analysis of its dependence on distance and on the resonance frequency of bubbles is performed.

Kukarkin, A B; Zhileikin, Ya M

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" from the National Library of EnergyBeta (NLEBeta).
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221

Nonlinear acoustic wave generation in a three-phase seabed  

E-Print Network [OSTI]

Generation of an acoustic wave by two pump sound waves is studied in a three-phase marine sediment that consists of a solid frame and the pore water with air bubbles in it. To avoid shock-wave formation the interaction is considered in the frequency range where there is a significant amount of sound velocity dispersion. Nonlinear equations are obtained to describe the interaction of acoustic waves in the presence of air bubbles. An expression for the amplitude of the generated wave is obtained and numerical analysis of its dependence on distance and on the resonance frequency of bubbles is performed.

A. B. Kukarkin; N. I. Pushkina; Ya. M. Zhileikin

2015-03-03T23:59:59.000Z

222

Acoustic waves in a Biot-type porous snow model: The fast slow wave in light snow  

E-Print Network [OSTI]

Wave velocities, attenuation and reflection coefficients in snow can not be explained by the widely used elastic or viscoelastic models for wave propagation. Instead, Biot's model of wave propagation in porous materials should be used. However, the application of Biot's model is difficult due to the large property space of the underlying porous material. Here we use the properties of ice and air as well as empirical relationships to define the properties of snow as a function of porosity. This reduction allows to predict phase velocities and attenuation of the shear- and compressional-waves as functions of porosity or density. For light snow the peculiarity was found that the velocity of the compressional wave of the first kind is lower than the compressional wave of the second kind that is commonly referred to as the "slow" wave. The reversal of the velocities comes with an increase of attenuation for the first compressional wave. This is in line with the common observation that sound is strongly absorbed af...

Sidler, Rolf

2015-01-01T23:59:59.000Z

223

Measurements of elastic modulus using laser-induced surface waves  

SciTech Connect (OSTI)

In general, the mechanical testing methods that are utilized for alloys and polymers, e.g., dogbone, rheovibron, etc., are not applicable to thin film structures. We wish to report noncontacting measurements of the surface acoustic wave (SAW) velocity and the elastic modulus applicable to thin films of moderate thickness. An accompanying paper extends this technique to smaller film dimensions. A 15 ns pulsed YAG laser was used as the energy source to thermoelastically excite surface waves. The propagation of the waves was then observed by a second, independent He-Ne laser at a distance from the excitation spot. using the knife edge/beam deflection technique. A cylindrical lens was used to reduce the energy loading of the YAG laser on the sample to avoid damaging the surface of the specimen. The Rayleigh wave velocity is calculated from measurements of the arrival time of the surface wave as a function of distance from the ND:YAG laser spot. The shear modulus, G, can be determined from the measured speed of the surface waves, V, the specimen density, p, and Poisson`s ratio, v, according to the following relationship: V = R(v){sm_bullet}(G/p){sup {1/2}} where R(v), expressed as (0.862 + 1.14v)/(l + v), is the ratio of the Rayleigh wave velocity to the shear wave velocity and ranges from 0.86 to 0.95 Table below lists the measured surface wave velocities and the calculated shear modulus for our experimental results and the published values. Excellent agreement is observed. The depth of the SAW is approximately equal to the SAW wavelength which is approximately the laser spot size. Typically 30 {mu}m spot sizes can be readily achieved. In conclusion, SAW velocities and the modulus of elasticity of various materials have been measured. We have demonstrated that this non-contacting method can be used to characterize moderately thin films.

Chang, D.J.; Amimoto, S.T.; Gross, R.W.F. [Aerospace Corporation, Los Angeles, CA (United States); Glenn, T. [Massachusetts Institute of Technology, Cambridge, MA (United States)

1995-12-31T23:59:59.000Z

224

Electron dynamics in surface acoustic wave devices  

E-Print Network [OSTI]

-dimensional nanostructures one can create a series of dynamic quantum dots corresponding to the minima of the travelling electric wave, and each dot carries a single electron at the SAW velocity (? 2800 m/s). These devices may be of use in developing future quantum...

Thorn, Adam Leslie

2009-10-13T23:59:59.000Z

225

Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen Satish Pullammanappallil  

E-Print Network [OSTI]

Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen Satish to compute travel times for seismic waves. However, in practice, we have to solve the inverse problem: travel synthetic seismic models shows that large population sizes are crit- ical to generating good seismic

Louis, Sushil J.

226

Group-velocity tomography of South America and the surrounding oceans  

E-Print Network [OSTI]

Group-velocity tomography of South America and the surrounding oceans Oleg Vdovin,1 Jose¨ A. Rial,2 propagating across South America and the surrounding oceans. Broad-band waveform data from about 765 events and show that the average resolution across South America is about 60^80 for Rayleigh waves and 70

Ritzwolle, Mike

227

Rotating concave eddy current probe  

SciTech Connect (OSTI)

A rotating concave eddy current probe for detecting fatigue cracks hidden from view underneath the head of a raised head fastener, such as a buttonhead-type rivet, used to join together structural skins, such as aluminum aircraft skins. The probe has a recessed concave dimple in its bottom surface that closely conforms to the shape of the raised head. The concave dimple holds the probe in good alignment on top of the rivet while the probe is rotated around the rivet's centerline. One or more magnetic coils are rigidly embedded within the probe's cylindrical body, which is made of a non-conducting material. This design overcomes the inspection impediment associated with widely varying conductivity in fastened joints.

Roach, Dennis P. (Albuquerque, NM); Walkington, Phil (Albuquerque, NM); Rackow, Kirk A. (Albuquerque, NM); Hohman, Ed (Albuquerque, NM)

2008-04-01T23:59:59.000Z

228

Constraints on Neutrino Velocities Revisited  

E-Print Network [OSTI]

With a minimally modified dispersion relation for neutrinos, we reconsider the constraints on superluminal neutrino velocities from bremsstrahlung effects in the laboratory frame. Employing both the direct calculation approach and the virtual Z-boson approach, we obtain the generic decay width and energy loss rate of a superluminal neutrino with general energy. The Cohen-Glashow's analytical results for neutrinos with a relatively low energy are confirmed in both approaches. We employ the survival probability instead of the terminal energy to assess whether a neutrino with a given energy is observable or not in the OPERA experiment. Moreover, using our general results we perform systematical analyses on the constraints arising from the Super-Kamiokande and IceCube experiments.

Yunjie Huo; Tianjun Li; Yi Liao; Dimitri V. Nanopoulos; Yonghui Qi

2012-01-27T23:59:59.000Z

229

Cold Plasma Wave Analysis in Magneto-Rotational Fluids  

E-Print Network [OSTI]

This paper is devoted to investigate the cold plasma wave properties. The analysis has been restricted to the neighborhood of the pair production region of the Kerr magnetosphere. The Fourier analyzed general relativistic magnetohydrodynamical equations are dealt under special circumstances and dispersion relations are obtained. We find the $x$-component of the complex wave vector numerically. The corresponding components of the propagation vector, attenuation vector, phase and group velocities are shown in graphs. The direction and dispersion of waves are investigated.

M. Sharif; Umber Sheikh

2010-05-25T23:59:59.000Z

230

Electromagnetic waves with nonlinear dispersion law  

E-Print Network [OSTI]

Last year physicists in Europe have measured the velocity of the neutrinos particles. They found the neutrinos moving faster than the speed of light in vacuum. This result means that Einstein's relativity principle and its consequences in modern physics need a global additional renovation. In present paper the part of this problem is considered in terms of basic Maxwell's method only. By means of introduction a diffusion like displacement current the new super wave equation was derived, which permits of its solution be described the electromagnetic waves moving some faster than the conventional speed of light in vacuum especially in a gamma ray of a very short wave length region. The unique properties of these waves are that they undergo nonlinear dispersion law, uppermost limit of which is restricted. Discussion of further experimental problems and a number of estimations are given for the macro physic super wave equations also.

Pavel Mednis

2012-02-08T23:59:59.000Z

231

Cavitation controlled acoustic probe for fabric spot cleaning and moisture monitoring  

DOE Patents [OSTI]

A method and apparatus are provided for monitoring a fabric. An acoustic probe generates acoustic waves relative to the fabric. An acoustic sensor, such as an accelerometer is coupled to the acoustic probe for generating a signal representative of cavitation activity in the fabric. The generated cavitation activity representative signal is processed to indicate moisture content of the fabric. A feature of the invention is a feedback control signal is generated responsive to the generated cavitation activity representative signal. The feedback control signal can be used to control the energy level of the generated acoustic waves and to control the application of a cleaning solution to the fabric.

Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Raptis, Apostolos C. (Downers Grove, IL)

1997-01-01T23:59:59.000Z

232

Seismic Velocity Estimation from Time Migration Velocities M. K. Cameron, S. B. Fomel, J. A. Sethian  

E-Print Network [OSTI]

Seismic Velocity Estimation from Time Migration Velocities M. K. Cameron, S. B. Fomel, J. A the problem of estimating seismic velocities inside the earth which is necessary for obtaining seismic images in regular Cartesian coordinates. We derive a relation between the true seismic velocities and the routinely

Sethian, James A.

233

Millimeter Wave Cloud Radar (MMCR) Handbook  

SciTech Connect (OSTI)

The millimeter cloud radar (MMCR) systems probe the extent and composition of clouds at millimeter wavelengths. The MMCR is a zenith-pointing radar that operates at a frequency of 35 GHz. The main purpose of this radar is to determine cloud boundaries (e.g., cloud bottoms and tops). This radar will also report radar reflectivity (dBZ) of the atmosphere up to 20 km. The radar possesses a doppler capability that will allow the measurement of cloud constituent vertical velocities.

KB Widener; K Johnson

2005-01-30T23:59:59.000Z

234

Excavatability Assessment of Weathered Sedimentary Rock Mass Using Seismic Velocity Method  

SciTech Connect (OSTI)

Seismic refraction method is one of the most popular methods in assessing surface excavation. The main objective of the seismic data acquisition is to delineate the subsurface into velocity profiles as different velocity can be correlated to identify different materials. The physical principal used for the determination of excavatability is that seismic waves travel faster through denser material as compared to less consolidated material. In general, a lower velocity indicates material that is soft and a higher velocity indicates more difficult to be excavated. However, a few researchers have noted that seismic velocity method alone does not correlate well with the excavatability of the material. In this study, a seismic velocity method was used in Nusajaya, Johor to assess the accuracy of this seismic velocity method with excavatability of the weathered sedimentary rock mass. A direct ripping run by monitoring the actual production of ripping has been employed at later stage and compared to the ripper manufacturer's recommendation. This paper presents the findings of the seismic velocity tests in weathered sedimentary area. The reliability of using this method with the actual rippability trials is also presented.

Bin Mohamad, Edy Tonnizam; Noor, Muhazian Md; Isa, Mohamed Fauzi Bin Md.; Mazlan, Ain Naadia [Department of Geotechnics and Transportation, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai. Johor (Malaysia); Saad, Rosli [Universiti Sains Malaysia, Penang (Malaysia)

2010-12-23T23:59:59.000Z

235

Few-cycle optical probe-pulse for investigation of relativistic laser-plasma interactions  

SciTech Connect (OSTI)

The development of a few-cycle optical probe-pulse for the investigation of laser-plasma interactions driven by a Ti:sapphire, 30 Terawatt (TW) laser system is described. The probe is seeded by a fraction of the driving laser's energy and is spectrally broadened via self-phase modulation in a hollow core fiber filled with a rare gas, then temporally compressed to a few optical cycles via chirped mirrors. Shadowgrams of the laser-driven plasma wave created in relativistic electron acceleration experiments are presented with few-fs temporal resolution, which is shown to be independent of post-interaction spectral filtering of the probe-beam.

Schwab, M. B.; Sävert, A.; Polz, J.; Schnell, M.; Rinck, T.; Möller, M.; Hansinger, P. [Insitut für Optik und Quantenelektronik, Max-Wien-Platz 1, 07743 Jena (Germany)] [Insitut für Optik und Quantenelektronik, Max-Wien-Platz 1, 07743 Jena (Germany); Jäckel, O.; Paulus, G. G.; Kaluza, M. C. [Insitut für Optik und Quantenelektronik, Max-Wien-Platz 1, 07743 Jena (Germany) [Insitut für Optik und Quantenelektronik, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena (Germany); Veisz, L. [Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Straße 1, 85748 Garching (Germany)] [Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Straße 1, 85748 Garching (Germany)

2013-11-04T23:59:59.000Z

236

Bubbly Flow Experiment in Channel Using an Optical Probe and Tracking Algorithm  

E-Print Network [OSTI]

was inserted through a porous media at three superficial gas velocities: 4.6 mm/s, 2.5 mm/s, and 1.4 mm/s. Two techniques were applied in the experiment to measure the bubbly flow: an optical probe and an in-house developed tracking algorithm. Measurements...

Khan, Abdul

2012-10-19T23:59:59.000Z

237

Vortices in Brain waves  

E-Print Network [OSTI]

2003). Vortices in Brain Waves 62. M. E. Raichle, ScienceVORTICES IN BRAIN WAVES WALTER J. FREEMAN Department ofthat is recorded in brain waves (electroencephalogram, EEG).

Freeman, Walter J III; Vitiello, Giuseppe

2010-01-01T23:59:59.000Z

238

Large-amplitude circularly polarized electromagnetic waves in magnetized plasma  

SciTech Connect (OSTI)

We consider large-amplitude circularly polarized (LACP) waves propagating in a magnetized plasma. It is well-known that the dispersion relation for such waves coincides with the dispersion relation given by the linear theory. We develop the model of LACP wave containing a finite population of Cerenkov resonant particles. We find that the current of resonant particles modifies the linear dispersion relation. Dispersion curves of low-frequency (i.e., whistler and magnetosonic) waves are shifted toward larger values of the wave vector, i.e., waves with arbitrarily large wavelengths do not exist in this case. Dispersion curves of high-frequency waves are modified so that the wave phase velocity becomes smaller than the speed of light.

Vasko, I. Y., E-mail: vaskoiy@gmail.com; Artemyev, A. V.; Zelenyi, L. M. [Space Research Institute, RAS, Moscow (Russian Federation)] [Space Research Institute, RAS, Moscow (Russian Federation)

2014-05-15T23:59:59.000Z

239

Backward wave propagation in left-handed media with isotropic and anisotropic  

E-Print Network [OSTI]

Backward wave propagation in left-handed media with isotropic and anisotropic permittivity tensors medium is investigated from a purely wave propagation point of view. The functional form for the index-velocity vectors are antiparallel. It is shown that, in the case considered, the backward-wave propagation can

Mojahedi, Mohammad

240

Long duration ash probe  

DOE Patents [OSTI]

A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during soot blowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon. 8 figs.

Hurley, J.P.; McCollor, D.P.; Selle, S.J.

1994-07-26T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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.


241

Long duration ash probe  

DOE Patents [OSTI]

A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during sootblowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon.

Hurley, John P. (Grand Forks, ND); McCollor, Don P. (Grand Forks, ND); Selle, Stanley J. (Grand Forks, MN)

1994-01-01T23:59:59.000Z

242

Probing Organic Transistors with Infrared Beams  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Probing Organic Transistors with Infrared Beams Probing Organic Transistors with Infrared Beams Print Wednesday, 26 July 2006 00:00 Silicon-based transistors are well-understood,...

243

Mapping the nano-Hertz gravitational wave sky  

E-Print Network [OSTI]

We describe a new method for extracting gravitational wave signals from pulsar timing data. We show that any gravitational wave signal can be decomposed into an orthogonal set of sky maps, with the number of maps equal to the number of pulsars in the timing array. These maps may be used as a basis to construct gravitational wave templates for any type of source, including collections of point sources. A variant of the standard Hellings-Downs correlation analysis is recovered for statistically isotropic signals. The template based approach allows us to probe potential anisotropies in the signal and produce maps of the gravitational wave sky.

Neil J. Cornish; Rutger van Haasteren

2014-06-19T23:59:59.000Z

244

Optic probe for semiconductor characterization  

DOE Patents [OSTI]

Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

Sopori, Bhushan L. (Denver, CO); Hambarian, Artak (Yerevan, AM)

2008-09-02T23:59:59.000Z

245

Differential probes aid flow measurement  

SciTech Connect (OSTI)

Nonconstricting differential pressure flow probes which help solve the problems of clogging, wear, and pressure loss at the Seawater Filtration Facility in Saudi Arabia are described. Treated seawater is pumped into oil-bearing formations for secondary recovery. Figures showing principle of operation for probes, installation schematic and long-term accuracy results (flow probes vs. orifice meters) are presented. The new diamond-shaped design flow sensor offers accurate flow measurement with low permanent pressure loss, which translates into cost savings for the operator.

Mesnard, D.R.

1982-07-01T23:59:59.000Z

246

Probe Spin-Velocity Dependent New Interactions by Spin Relaxation Times of Polarized $^{3}He$ Gas  

E-Print Network [OSTI]

We have studied how to constrain the $\\alpha\\vec{\\sigma}\\cdot\\vec{v}$ type interactions with the relaxation time of spin polarized noble gases in magnetic fields. Using the longest $T_{2}$ measured in the laboratory and the earth as the source, we obtained constraints on three new interactions. We present a new experimental upper bound to the vector-axial-vector($V_{VA}$) type interaction for ranges between $1\\sim10^{8}$m. In combination with the previous result, we set the most stringent experiment limits on $g_{V}g_{A}$ ranging from $\\sim\\mu m$ to $\\sim10^{8}$m. We improve the laboratory limit to the axial-axial-vector($V_{AA}$) type interaction by $\\sim2$ orders or more for distances below $\\sim1$cm. To our best knowledge, we report the first experiment upper limit on torsion induced by the earth on its surface.

Y. Zhang; G. A. Sun; S. M. Peng; C. B. Fu; Hao Guo; B. Q. Liu; H. Yan

2014-12-28T23:59:59.000Z

247

Numerical simulation of inviscid wave-current interaction with an FPSO  

E-Print Network [OSTI]

This study investigated Floating Production Storage and Offloading (FPSO) responses under wave and current interactions. A higher order boundary element method (HOBEM) was adopted to probe the behavior of an FPSO. Forces and moment of an FPSO were...

Bae, Sang-Yun

2009-05-15T23:59:59.000Z

248

Moreton Waves and EIT Waves Related to the Flare Events of June 3, 2012 and July 6, 2012  

E-Print Network [OSTI]

We present geometrical and kinematical analysis of Moreton waves and EIT waves observed on June 3, 2012 and Moreton waves observed on July 6, 2012. The Moreton waves were recorded in H$\\alpha$ images of Global Oscillation Network Group (GONG) archive and EIT waves obtained from SDO/AIA observations, especially in 193 nm channel. The observed wave of June 3 has angular span of about $70^{\\circ}$ with a broad wave front associated to NOAA active region 11496. It was found that the speed of the wave that started propagating at 17.53 UT is between 950 to 1500 km/s. Related to this wave occurrence, there was solar type II and III radio bursts. The speed of the EIT in this respect about 247 km/sec. On the other hand, the wave of July 6 may be associated to X1.1 class flare that occurred at 23.01 UT around the 11514 active region. From the kinematical analysis, the wave propagated with the initial velocity of about 1180 km/s which is in agreement with coronal shock velocity derived from type II radio burst observati...

Admiranto, A G; Yus'an, U; Puspitaningrum, E

2015-01-01T23:59:59.000Z

249

Assessment of the 296-S-21 Stack Sampling Probe Location  

SciTech Connect (OSTI)

Tests were performed to assess the suitability of the location of the air sampling probe on the 296-S-21 stack according to the criteria of ANSI N13.1-1999, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities. Pacific Northwest National Laboratory conducted most tests on a 3.67:1 scale model of the stack. CH2MHill also performed some limited confirmatory tests on the actual stack. The tests assessed the capability of the air-monitoring probe to extract a sample representative of the effluent stream. The tests were conducted for the practical combinations of operating fans and addressed: (1) Angular Flow--The purpose is to determine whether the velocity vector is aligned with the sampling nozzle. The average yaw angle relative to the nozzle axis should not be more than 20. The measured values ranged from 5 to 11 degrees on the scale model and 10 to 12 degrees on the actual stack. (2) Uniform Air Velocity--The gas momentum across the stack cross section where the sample is extracted should be well mixed or uniform. The uniformity is expressed as the variability of the measurements about the mean, the coefficient of variance (COV). The lower the COV value, the more uniform the velocity. The acceptance criterion is that the COV of the air velocity must be ?20% across the center two-thirds of the area of the stack. At the location simulating the sampling probe, the measured values ranged form 4 to 11%, which are within the criterion. To confirm the validity of the scale model results, air velocity uniformity measurements were made both on the actual stack and on the scale model at the test ports 1.5 stack diameters upstream of the sampling probe. The results ranged from 6 to 8% COV on the actual stack and 10 to 13% COV on the scale model. The average difference for the eight runs was 4.8% COV, which is within the validation criterion. The fact that the scale model results were slightly higher than the actual stack suggests that the other test results on the scale model are conservative relative to the actual stack. (3) Uniform Concentration of Tracer Gases--A uniform contaminant concentration in the sampling plane enables the extraction of samples that represent the true concentration. This was first tested using a tracer gas to represent gaseous effluents. The fan is a good mixer, so injecting the tracer downstream of the fans provides worst-case results. The acceptance criteria are that (1) the COV of the measured tracer gas concentration is ?20% across the center two-thirds of the sampling plane and (2) at no point in the sampling plane does the concentration vary from the mean by >30%. The results on the scale model at the point simulating the sampling probe ranged from 0.3 to 6 %COV, and the maximum single point deviation from the mean was -10%. (4) Uniform Concentration of Tracer Particles--Uniformity in contaminant concentration at the sampling probe was further demonstrated using tracer particles large enough to exhibit inertial effects. Particles of 10-?m aerodynamic diameter were used. The acceptance criterion is that the COV of particle concentration is ?20% across the center two-thirds of the sampling plane. The scale model results ranged form 2 to 9%. Based on these tests, the location of the air sampling probe on the 296-S-21 stack meets the requirements of the ANSI/HPS N13.1-1999 standard.

Glissmeyer, John A.

2006-09-08T23:59:59.000Z

250

Gravitational Waves in G4v  

E-Print Network [OSTI]

Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown t...

Mead, Carver

2015-01-01T23:59:59.000Z

251

3-D seismic velocity and attenuation structures in the geothermal field  

SciTech Connect (OSTI)

We conducted delay time tomography to determine 3-D seismic velocity structures (Vp, Vs, and Vp/Vs ratio) using micro-seismic events in the geothermal field. The P-and S-wave arrival times of these micro-seismic events have been used as input for the tomographic inversion. Our preliminary seismic velocity results show that the subsurface condition of geothermal field can be fairly delineated the characteristic of reservoir. We then extended our understanding of the subsurface physical properties through determining of attenuation structures (Qp, Qs, and Qs/Qp ratio) using micro-seismic waveform. We combined seismic velocities and attenuation structures to get much better interpretation of the reservoir characteristic. Our preliminary attanuation structures results show reservoir characterization can be more clearly by using the 3-D attenuation model of Qp, Qs, and Qs/Qp ratio combined with 3-D seismic velocity model of Vp, Vs, and Vp/Vs ratio.

Nugraha, Andri Dian [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)] [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia); Syahputra, Ahmad [Geophyisical Engineering, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)] [Geophyisical Engineering, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia); Fatkhan,; Sule, Rachmat [Applied Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)] [Applied Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)

2013-09-09T23:59:59.000Z

252

Switchable stiffness scanning microscope probe  

E-Print Network [OSTI]

Atomic Force Microscopy (AFM) has rapidly gained widespread utilization as an imaging device and micro/nano-manipulator during recent years. This thesis investigates the new concept of a dual stiffness scanning probe with ...

Mueller-Falcke, Clemens T. (Clemens Tobias)

2005-01-01T23:59:59.000Z

253

Volume203,number2,3 CHEMICAL PHYSICS LETTERS 19February1993 Transient grating spectroscopy of exciton sound waves  

E-Print Network [OSTI]

of exciton sound waves in dense exciton fluids Jan A. Leegwater and Shaul Mukamel Department of Chemistry to that of sound waves in an ordinary gas. A method to probe these motions using transient grating with strong pump density may disappear and reap- pear later. The physical mechanism is analogous to that of sound waves

Mukamel, Shaul

254

High-pressure sound velocities and elasticity of aluminous MgSiO3 perovskite to 45 GPa: Implications for lateral heterogeneity in Earth's  

E-Print Network [OSTI]

High-pressure sound velocities and elasticity of aluminous MgSiO3 perovskite to 45 GPa lateral variations of seismic wave speeds in Earth's lower mantle are due at least in part to a chemical, J. M., J. Zhang, J. Shu, S. V. Sinogeikin, and J. D. Bass (2005), High-pressure sound velocities

Jackson, Jennifer M.

255

Coda wave interferometry 1 Coda wave interferometry  

E-Print Network [OSTI]

Coda wave interferometry 1 Coda wave interferometry An interferometer is an instrument that is sensitive to the interference of two or more waves (optical or acoustic). For example, an optical interferometer uses two interfering light beams to measure small length changes. Coda wave interferometry

Snieder, Roel

256

Kink waves in solar spicules: observation and modelling  

E-Print Network [OSTI]

Height series of Doppler observation at the solar limb (covering 3800 - 8700 km distance above the photosphere) in $H_{\\alpha}$ spectral line obtained by big coronagraph of Abastumani Astrophysical Observatory \\citep{khu} show the periodic spatial distribution of Doppler velocities in spicules. We suggest that the periodic spatial distribution is caused by propagating kink waves in spicule. The wave length is found to be $\\sim$ 3500 km. Numerical modelling of kink wave propagation from the photosphere to observed heights gives the wave length of kink waves at the photosphere to be $\\sim$ 1000 km, which indicates to the granular origin of the waves. The period of waves is estimated to be in the range of 35-70 s.

V. Kukhianidze; T. V. Zaqarashvili; E. Khutsishvili

2005-10-14T23:59:59.000Z

257

Stable operating regime for traveling wave devices  

DOE Patents [OSTI]

Autophase stability is provided for a traveling wave device (TWD) electron beam for amplifying an RF electromagnetic wave in walls defining a waveguide for said electromagnetic wave. An off-axis electron beam is generated at a selected energy and has an energy noise inherently arising from electron gun. The off-axis electron beam is introduced into the waveguide. The off-axis electron beam is introduced into the waveguide at a second radius. The waveguide structure is designed to obtain a selected detuning of the electron beam. The off-axis electron beam has a velocity and the second radius to place the electron beam at a selected distance from the walls defining the waveguide, wherein changes in a density of the electron beam due to the RF electromagnetic wave are independent of the energy of the electron beam to provide a concomitant stable operating regime relative to the energy noise.

Carlsten, Bruce E. (Los Alamos, NM)

2000-01-01T23:59:59.000Z

258

Wave Properties of Isothermal Magneto-Rotational Fluids  

E-Print Network [OSTI]

In this paper, the isothermal plasma wave properties in the neighborhood of the pair production region for the Kerr black hole magnetosphere are discussed. We have considered the Fourier analyzed form of the perturbed general relativistic magnetohydrodynamical equations whose determinant leads to a dispersion relation. For the special scenario, the $x$-component of the complex wave vectors are numerically calculated. Respective components of the propagation vector, attenuation vector, phase and group velocities are shown in graphs. We have particularly investigated the existence of a Veselago medium and wave behavior (modes of waves dispersion

M. Sharif; Umber Sheikh

2009-08-28T23:59:59.000Z

259

Numerical Analysis of the Internal Kinematics and Dynamics of Three-dimensional Breaking Waves on B. Biausser, S.T. Grilli, P. Frauni  

E-Print Network [OSTI]

Numerical Analysis of the Internal Kinematics and Dynamics of Three-dimensional Breaking Waves/Navier-Stokes solver. Analysis of wave profiles and kinematics (velocity, vorticity, pressure) are carried out. Keyword the breaking and post-breaking in a three- dimensional numerical wave tank of a solitary wave over a sloping

Grilli, Stéphan T.

260

Quantum probes of timelike naked singularities in $2+1-$ dimensional power - law spacetimes  

E-Print Network [OSTI]

The formation of naked singularities in $2+1-$ dimensional power - law spacetimes in linear Einstein-Maxwell and Einstein-scalar theories sourced by azimuthally symmetric electric field and a self-interacting real scalar field respectively, are considered in view of quantum mechanics. Quantum test fields obeying the Klein-Gordon and Dirac equations are used to probe the classical timelike naked singularities developed at $r=0$. We show that when the classically singular spacetimes probed with scalar waves, the considered spacetimes remains singular. However, the spinorial wave probe of the singularity in the metric of a self-interacting real scalar field remains quantum regular. The notable outcome in this study is that the quantum regularity/singularity can not be associated with the energy conditions.

O. Gurtug; M. Halilsoy; S. Habib Mazharimousavi

2015-01-29T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Modeling of current characteristics of segmented Langmuir probe on DEMETER  

SciTech Connect (OSTI)

We model the current characteristics of the DEMETER Segmented Langmuir probe (SLP). The probe is used to measure electron density and temperature in the ionosphere at an altitude of approximately 700 km. It is also used to measure the plasma flow velocity in the satellite frame of reference. The probe is partitioned into seven collectors: six electrically insulated spherical segments and a guard electrode (the rest of the sphere and the small post). Comparisons are made between the predictions of the model and DEMETER measurements for actual ionospheric plasma conditions encountered along the satellite orbit. Segment characteristics are computed numerically with PTetra, a three-dimensional particle in cell simulation code. In PTetra, space is discretized with an unstructured tetrahedral mesh, thus, enabling a good representation of the probe geometry. The model also accounts for several physical effects of importance in the interaction of spacecraft with the space environment. These include satellite charging, photoelectron, and secondary electron emissions. The model is electrostatic, but it accounts for the presence of a uniform background magnetic field. PTetra simulation results show different characteristics for the different probe segments. The current collected by each segment depends on its orientation with respect to the ram direction, the plasma composition, the magnitude, and the orientation of the magnetic field. It is observed that the presence of light H{sup +} ions leads to a significant increase in the ion current branch of the I-V curves of the negatively polarized SLP. The effect of the magnetic field is demonstrated by varying its magnitude and direction with respect to the reference magnetic field. It is found that the magnetic field appreciably affects the electron current branch of the I-V curves of certain segments on the SLP, whereas the ion current branch remains almost unaffected. PTetra simulations are validated by comparing the computed characteristics and their angular anisotropy with the DEMETER measurements, as simulation results are found to be in good agreement with the measurements.

Imtiaz, Nadia; Marchand, Richard [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada)] [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada); Lebreton, Jean-Pierre [Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), CNRS-Université d'Orléans, Orléans Cedex (France)] [Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), CNRS-Université d'Orléans, Orléans Cedex (France)

2013-05-15T23:59:59.000Z

262

Dependence of synergy current driven by lower hybrid wave and electron cyclotron wave on the frequency and parallel refractive index of electron cyclotron wave for Tokamaks  

SciTech Connect (OSTI)

The physical mechanism of the synergy current driven by lower hybrid wave (LHW) and electron cyclotron wave (ECW) in tokamaks is investigated using theoretical analysis and simulation methods in the present paper. Research shows that the synergy relationship between the two waves in velocity space strongly depends on the frequency ? and parallel refractive index N{sub //} of ECW. For a given spectrum of LHW, the parameter range of ECW, in which the synergy current exists, can be predicted by theoretical analysis, and these results are consistent with the simulation results. It is shown that the synergy effect is mainly caused by the electrons accelerated by both ECW and LHW, and the acceleration of these electrons requires that there is overlap of the resonance regions of the two waves in velocity space.

Huang, J.; Chen, S. Y., E-mail: sychen531@163.com; Tang, C. J. [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China) [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China)

2014-01-15T23:59:59.000Z

263

Hand-held survey probe  

DOE Patents [OSTI]

A system for providing operational feedback to a user of a detection probe may include an optical sensor to generate data corresponding to a position of the detection probe with respect to a surface; a microprocessor to receive the data; a software medium having code to process the data with the microprocessor and pre-programmed parameters, and making a comparison of the data to the parameters; and an indicator device to indicate results of the comparison. A method of providing operational feedback to a user of a detection probe may include generating output data with an optical sensor corresponding to the relative position with respect to a surface; processing the output data, including comparing the output data to pre-programmed parameters; and indicating results of the comparison.

Young, Kevin L. (Idaho Falls, ID) [Idaho Falls, ID; Hungate, Kevin E. (Idaho Falls, ID) [Idaho Falls, ID

2010-02-23T23:59:59.000Z

264

The jump-off velocity of an impulsively loaded spherical shell  

SciTech Connect (OSTI)

We consider a constant temperature spherical shell of isotropic, homogeneous, linearly elastic material with density {rho} and Lame coefficients {lambda} and {mu}. The inner and outer radii of the shell are r{sub i} and r{sub o}, respectively. We assume that the inside of the shell is a void. On the outside of the shell, we apply a uniform, time-varying pressure p(t). We also assume that the shell is initially at rest. We want to compute the jump-off time and velocity of the pressure wave, which are the first time after t = 0 at which the pressure wave from the outer surface reaches the inner surface. This analysis computes the jump-off velocity and time for both compressible and incompressible materials. This differs substantially from [3], where only incompressible materials are considered. We will consider the behavior of an impulsively loaded, exponentially decaying pressure wave p(t) = P{sub 0{sup e}}{sup -{alpha}t}, where {alpha} {ge} 0. We notice that a constant pressure wave P(t) = P{sub 0} is a special case ({alpha} = 0) of a decaying pressure wave. Both of these boundary conditions are considered in [3].

Chabaud, Brandon M. [Los Alamos National Laboratory; Brock, Jerry S. [Los Alamos National Laboratory

2012-04-13T23:59:59.000Z

265

Plane waves Lumped systems  

E-Print Network [OSTI]

1 Impedance · Plane waves ­ Lumped systems S x y z Impedance · Plane waves ­ Lumped systems · open tube #12;2 Impedance · Plane waves ­ Lumped systems · closed tube Impedance · Cylindrical waves z x y r #12;3 Impedance · Cylindrical waves ­ Circumferential part n=0 n=1 n=2 n=3 Impedance · Cylindrical

Berlin,Technische Universität

266

Wave Propagation in Lipid Monolayers  

E-Print Network [OSTI]

Sound waves are excited on lipid monolayers using a set of planar electrodes aligned in parallel with the excitable medium. By measuring the frequency dependent change in the lateral pressure we are able to extract the sound velocity for the entire monolayer phase diagram. We demonstrate that this velocity can also be directly derived from the lipid monolayer compressibility and consequently displays a minimum in the phase transition regime. This minimum decreases from v0=170m/s for one component lipid monolayers down to vm=50m/s for lipid mixtures. No significant attenuation can be detected confirming an adiabatic phenomenon. Finally our data propose a relative lateral density oscillation of \\Delta\\rho/\\rho ~ 2% implying a change in all area dependent physical properties. Order of magnitude estimates from static couplings therefore predict propagating changes in surface potential of 1-50mV, 1 unit in pH (electrochemical potential) and 0.01{\\deg}K in temperature and fall within the same order of magnitude as physical changes measured during nerve pulse propagation. These results therefore strongly support the idea of propagating adiabatic sound waves along nerves as first thoroughly described by Kaufmann in 1989 and recently by Heimburg and Jackson, but claimed by Wilke already in 1912.

J. Griesbauer; A. Wixforth; M. F. Schneider

2010-05-26T23:59:59.000Z

267

Explicit dispersion relations for elastic waves in extremely deformed soft matter with application to nearly incompressible and auxetic materials  

E-Print Network [OSTI]

We analyze the propagation of elastic waves in soft materials subjected to finite deformations. We derive explicit dispersion relations, and apply these results to study elastic wave propagation in (i) nearly incompressible materials such as biological tissues and polymers, and (ii) negative Poisson's ratio or auxetic materials. We find that for nearly incompressible materials transverse wave velocities exhibit strong dependence on direction of propagation and initial strain state, whereas the longitudinal component is not affected significantly until extreme levels of deformations are attained. For highly compressible materials, we show that both pressure and shear wave velocities depend strongly on initial deformation and direction of propagation. When compression is applied, longitudinal wave velocity decreases in positive bulk modulus materials, and increases for negative bulk modulus materials; this is regardless the direction of wave prorogation. We demonstrate that finite deformations influence elastic wave propagation through combinations of induced effective compressibility and stiffness.

Pavel Galich; Stephan Rudykh

2014-12-31T23:59:59.000Z

268

Robust Autoresonant Excitation in the Plasma Beat-Wave Accelerator R. R. Lindberg,* A. E. Charman, and J. S. Wurtele  

E-Print Network [OSTI]

scheme is proposed, based on autoresonant phase locking of the Langmuir wave to the slowly chirped beat ponderomotively on the plasma to resonantly excite a large-amplitude, high-phase-velocity plasma wave suitableRobust Autoresonant Excitation in the Plasma Beat-Wave Accelerator R. R. Lindberg,* A. E. Charman

Friedland, Lazar

269

Geophys. J. Znt. (1991) 107, 531-543 Effects of point singularities on shear-wave propagation in  

E-Print Network [OSTI]

Geophys. J. Znt. (1991) 107, 531-543 Effects of point singularities on shear-wave propagation In most directions of propagation in anisotropic solids, seismic shear waves split in regular small to cause conventional cusps on the group-velocity wave surfaces. The effects of propagation near

Edinburgh, University of

270

Modeling velocity dispersion In Gypsy site, Oklahoma  

E-Print Network [OSTI]

Discrepancies in interval velocities estimated from vertical well measurements made with different source central frequencies at Gypsy site could be primarily explained in terms of intrinsic attenuation. Four intervals ...

Alsaadan, Sami Ibrahim

2010-01-01T23:59:59.000Z

271

Observations and modeling of wave-acceleration-induced sediment transport in the surfzone  

E-Print Network [OSTI]

Onshore sediment transport and sandbar migration are important to the morphological evolution of beaches, but are not understood well. Here, a new model that accounts for accelerations of wave-orbital velocities predicts ...

Hoefel, Fernanda Gemael, 1973-

2004-01-01T23:59:59.000Z

272

Modeling fault-zone guided waves of microearthquakes in a geothermal...  

Open Energy Info (EERE)

the identification and modeling of such guided waves is an effective tool to locate fracture-induced, low-velocity fault-zone structures in geothermal fields. Authors Lou, M.;...

273

E-Print Network 3.0 - averaged teleseismic p-wave Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Zone: A joint teleseismic and local P tomographic study Summary: because the unconsolidated sediment layer has a very low P wave velocity (1.8 kmsec) Chiu et al., 1992......

274

Turbulent combined wave-current boundary layer model for application in coastal waters  

E-Print Network [OSTI]

Accurately predicting transport processes, including sediment transport, in the coastal environment is impossible without correct current velocity and shear stress information. A combined wave-current boundary layer theory ...

Humbyrd, Chelsea Joy

2012-01-01T23:59:59.000Z

275

Gravitational waves and gamma-ray bursts  

E-Print Network [OSTI]

Gamma-Ray Bursts are likely associated with a catastrophic energy release in stellar mass objects. Electromagnetic observations provide important, but indirect information on the progenitor. On the other hand, gravitational waves emitted from the central source, carry direct information on its nature. In this context, I give an overview of the multi-messenger study of gamma-ray bursts that can be carried out by using electromagnetic and gravitational wave observations. I also underline the importance of joint electromagnetic and gravitational wave searches, in the absence of a gamma-ray trigger. Finally, I discuss how multi-messenger observations may probe alternative gamma-ray burst progenitor models, such as the magnetar scenario.

Alessandra Corsi; for the LIGO Scientific Collaboration; for the Virgo Collaboration

2012-05-11T23:59:59.000Z

276

Smooth sandwich gravitational waves  

E-Print Network [OSTI]

Gravitational waves which are smooth and contain two asymptotically flat regions are constructed from the homogeneous pp-waves vacuum solution. Motion of free test particles is calculated explicitly and the limit to an impulsive wave is also considered.

J. Podolsky

1998-07-16T23:59:59.000Z

277

Acoustic measurement of potato cannon velocity  

E-Print Network [OSTI]

This article describes measurement of potato cannon velocity with a digitized microphone signal. A microphone is attached to the potato cannon muzzle and a potato is fired at an aluminum target about 10 m away. The potato's flight time can be determined from the acoustic waveform by subtracting the time in the barrel and time for sound to return from the target. The potato velocity is simply the flight distance divided by the flight time.

Courtney, M; Courtney, Amy; Courtney, Michael

2006-01-01T23:59:59.000Z

278

Guarded capacitance probes for measuring particle concentration and flow  

DOE Patents [OSTI]

Guarded capacitance probe structures are constructed with guard electrodes surrounding one or more sensor electrodes and ground electrodes or grounded surfaces surrounding the guard electrodes. In a one sensor embodiment, the probe utilizes an apertured sensor electrode and the guard electrode both surrounds the sensor electrode and fills the aperture. This embodiment is particularly useful for measuring particle concentration in a fluid suspension contained within a vessel or pipe. The portion of the guard electrode within the aperture of the sensor electrode prevents electric field lines from emanating from the sensor electrode into the fluid suspension and toward infinity. A two sensor embodiment of the probe is useful for measuring flow velocities of fluid suspensions through cross correlation of the outputs generated by each sensor. The relative dimensions of the guard and sensor electrodes are selected to provide the most accurate measurements by confining the electric lines emanating from the sensor electrode or electrodes and terminating on the surrounding grounded surfaces to a small measurement volume of the fluid suspension near the vessel or pipe wall. 14 figs.

Louge, M.Y.

1995-10-17T23:59:59.000Z

279

Nuclear Physics with Electroweak Probes  

E-Print Network [OSTI]

In recent years, the italian theoretical Nuclear Physics community has played a leading role in the development of a unified approach, allowing for a consistent and fully quantitative description of the nuclear response to electromagnetic and weak probes. In this paper I review the main achievements in both fields, point out some of the open problems, and outline the most promising prospects.

Omar Benhar

2009-02-26T23:59:59.000Z

280

Distances and Metallicities of High- and Intermediate-Velocity Clouds  

E-Print Network [OSTI]

A table is presented that summarizes published absorption line measurements for the high- and intermediate velocity clouds (HVCs and IVCs). New values are derived for N(HI) in the direction of observed probes, in order to arrive at reliable abundances and abundance limits (the HI data are described in Paper II). Distances to stellar probes are revisited and calculated consistently, in order to derive distance brackets or limits for many of the clouds, taking care to properly interpret non-detections. The main conclusions are the following. 1) Absolute abundances have been measured using lines of SII, NI and OI, with the following resulting values: ~0.1 solar for one HVC (complex C), ~0.3 solar for the Magellanic Stream, ~0.5 solar for a southern IVC, and ~ solar for two northern IVCs (the IV Arch and LLIV Arch). Finally, approximate values in the range 0.5-2 solar are found for three more IVCs. 2) Depletion patterns in IVCs are like those in warm disk or halo gas. 3) Most distance limits are based on strong UV lines of CII, SiII and MgII, a few on CaII. Distance limits for major HVCs are >5 kpc, while distance brackets for several IVCs are in the range 0.5-2 kpc. 4) Mass limits for major IVCs are 0.5-8x10^5 M_sun, but for major HVCs they are >10^6 M_sun. 5) The CaII/HI ratio varies by up to a factor 2-5 within a single cloud, somewhat more between clouds. 6) The NaIHI ratio varies by a factor >10 within a cloud, and even more between clouds. Thus, CaII can be useful for determining both lower and upper distance limits, but NaI only yields upper limits.

B. P. Wakker

2001-02-08T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Sensor Based on Extending the Concept of Fidelity to Classical Waves  

E-Print Network [OSTI]

We propose and demonstrate a remote sensor scheme by applying the quantum mechanical concept of fidelity loss to classical waves. The sensor makes explicit use of time-reversal invariance and spatial reciprocity in a wave chaotic system to sensitively and remotely measure the presence of small perturbations. The loss of fidelity is measured through a classical wave-analog of the Loschmidt echo by employing a single-channel time-reversal mirror to rebroadcast a probe signal into the perturbed system. We also introduce the use of exponential amplification of the probe signal to partially overcome the effects of propagation losses and to vary the sensitivity.

Biniyam Tesfaye Taddese; James Hart; Thomas M. Antonsen; Edward Ott; Steven M. Anlage

2009-09-28T23:59:59.000Z

282

Tidal waves as yrast states in transitional nuclei  

E-Print Network [OSTI]

The yrast states of transitional nuclei are described as quadrupole waves running over the nuclear surface, which we call tidal waves. In contrast to a rotor, which generates angular momentum by increasing the angular velocity at approximately constant deformation, a tidal wave generates angular momentum by increasing the deformation at approximately constant angular velocity. The properties of the tidal waves are calculated by means of the cranking model in a microscopic way. The calculated energies and E2 transition probabilities of the yrast states in the transitional nuclides with $Z$= 44, 46, 48 and $N=56, 58, ..., 66$ reproduce the experiment in detail. The nonlinear response of the nucleonic orbitals results in a strong coupling between shape and single particle degrees of freedom.

S. Frauendorf; Y. Gu; J. Sun

2010-02-16T23:59:59.000Z

283

LISA as a dark energy probe  

E-Print Network [OSTI]

Recently it was shown that the inclusion of higher signal harmonics in the inspiral signals of binary supermassive black holes (SMBH) leads to dramatic improvements in parameter estimation with the Laser Interferometer Space Antenna (LISA). In particular, the angular resolution becomes good enough to identify the host galaxy or galaxy cluster, in which case the redshift can be determined by electromagnetic means. The gravitational wave signal also provides the luminosity distance with high accuracy, and the relationship between this and the redshift depends sensitively on the cosmological parameters, such as the equation-of-state parameter $w=p_{\\rm DE}/\\rho_{\\rm DE}$ of dark energy. With a single binary SMBH event at $z < 1$ having appropriate masses and orientation, one would be able to constrain $w$ to within a few percent. We show that, if the measured sky location is folded into the error analysis, the uncertainty on $w$ goes down by an additional factor of 2-3, leaving weak lensing as the only limiting factor in using LISA as a dark energy probe.

K G Arun; Chandra Kant Mishra; Chris Van Den Broeck; B R Iyer; B S Sathyaprakash; Siddhartha Sinha

2009-04-20T23:59:59.000Z

284

Dust-acoustic solitary waves in dusty plasmas with non-thermal ions  

SciTech Connect (OSTI)

Most studies on dusty plasmas have assumed that electrons and ions follow Maxwellian distributions. However, in the presence of energetic ions, the distribution of ions tends to be non-Maxwellian. It is shown here that the existence of non-thermal ions would increase the phase velocity of a dust-acoustic wave. It is also found that the change in the phase velocity profoundly affects the characteristics of a dust-acoustic solitary wave.

Asgari, H.; Muniandy, S. V.; Wong, C. S. [Plasma Technology Research Center, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2013-02-15T23:59:59.000Z

285

Studies of laser-driven radiative blast waves  

SciTech Connect (OSTI)

We have performed two sets of experiments looking at laser-driven radiating blast waves. In one set of experiments the effect of a drive laser's passage through a background gas on the hydrodynamical evolution of blast waves was examined. It was found that the laser's passage heats a channel in the gas, creating a region where a portion of the blast wave front had an increased velocity, leading to the formation of a bump-like protrusion on the blast wave. The second set of experiments involved the use of regularly spaced wire arrays to induce perturbations on a blast wave surface. The decay of these perturbations as a function of time was measured for various wave number perturbations and found to be in good agreement with theoretical predictions.

Edwards, M J; Hansen, J; Edens, A; Ditmire, T; Adams, R; Rambo, P; Ruggles, L; Smith, I; Porter, J

2004-04-29T23:59:59.000Z

286

Cantilevered probe detector with piezoelectric element  

DOE Patents [OSTI]

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Adams, Jesse D. (Reno, NV); Sulchek, Todd A. (Oakland, CA); Feigin, Stuart C. (Reno, NV)

2012-07-10T23:59:59.000Z

287

Cantilevered probe detector with piezoelectric element  

DOE Patents [OSTI]

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Adams, Jesse D; Sulchek, Todd A; Feigin, Stuart C

2014-04-29T23:59:59.000Z

288

Cantilevered probe detector with piezoelectric element  

DOE Patents [OSTI]

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Adams, Jesse D; Sulchek, Todd A; Feigin, Stuart C

2013-04-30T23:59:59.000Z

289

Handheld force-controlled ultrasound probe  

E-Print Network [OSTI]

An hand-held force controlled ultrasound probe has been developed. The controller maintains a prescribed contact force between the probe and a patient's body. The device will enhance the diagnostic capability of free-hand ...

Gilbertson, Matthew Wright

2010-01-01T23:59:59.000Z

290

Coherent cooling of atoms in a frequency-modulated standing laser wave: Wave function and stochastic trajectory approaches  

SciTech Connect (OSTI)

The wave function of a moderately cold atom in a stationary near-resonant standing light wave delocalizes very fast due to wave packet splitting. However, we show that frequency modulation of the field can suppress packet splitting for some atoms whose specific velocities are in a narrow range. These atoms remain localized in a small space for a long time. We demonstrate and explain this effect numerically and analytically. We also demonstrate that the modulated field can not only trap but also cool the atoms. We perform a numerical experiment with a large atomic ensemble having wide initial velocity and energy distributions. During the experiment, most of atoms leave the wave while the trapped atoms have a narrow energy distribution.

Argonov, V. Yu., E-mail: argonov@poi.dvo.ru [Russian Academy of Sciences, Pacific Oceanological Institute (Russian Federation)

2014-11-15T23:59:59.000Z

291

Investigation of Wave Energy Converter Effects on Wave Fields: A Modeling Sensitivity Study in Monterey Bay CA.  

SciTech Connect (OSTI)

A n indust ry standard wave modeling tool was utilized to investigate model sensitivity to input parameters and wave energy converter ( WEC ) array deploym ent scenarios. Wave propagation was investigated d ownstream of the WECs to evaluate overall near - and far - field effects of WEC arrays. The sensitivity study illustrate d that b oth wave height and near - bottom orbital velocity we re subject to the largest pote ntial variations, each decreas ed in sensitivity as transmission coefficient increase d , as number and spacing of WEC devices decrease d , and as the deployment location move d offshore. Wave direction wa s affected consistently for all parameters and wave perio d was not affected (or negligibly affected) by varying model parameters or WEC configuration .

Roberts, Jesse D.; Grace Chang; Jason Magalen; Craig Jones

2014-08-01T23:59:59.000Z

292

Topological Aspects of Wave Propagation  

E-Print Network [OSTI]

In the context of wave propagation on a manifold X, the characteristic functions are real valued functions on cotangent bundle of X that specify the allowable phase velocities of the waves. For certain classes of differential operators (e.g Maxwell's Equations) the associated characteristic functions have singularities. These singularities account for phenomena like conical refraction and the transformation of longitudinal waves into transversal ones (or viceversa). For a specific class of differential operators on surface, we prove that the singularities of the characteristic functions can be accounted from purely topological considerations. We also prove that there is a natural way to desingularsize the characteristic functions, and observe that this fact and Morse Theory establishes a specific connection between singularities and critical points of these functions. The relation between characteristic functions and differential operators is obtained through what is known as the symbol of the operator. We establish a connection between these symbols and holomorphic vector fields, which will provide us with symbols whose characteristic functions have interesting singularity sets.

Carlos Valero

2014-06-13T23:59:59.000Z

293

DETERMINATION OF NON-THERMAL VELOCITY DISTRIBUTIONS FROM SERTS LINEWIDTH OBSERVATIONS  

SciTech Connect (OSTI)

Non-thermal velocities obtained from the measurement of coronal Extreme Ultraviolet (EUV) linewidths have been consistently observed in solar EUV spectral observations and have been theorized to result from many plausible scenarios including wave motions, turbulence, or magnetic reconnection. Constraining these velocities can provide a physical limit for the available energy resulting from unresolved motions in the corona. We statistically determine a series of non-thermal velocity distributions from linewidth measurements of 390 emission lines from a wide array of elements and ionization states observed during the Solar Extreme Ultraviolet Research Telescope and Spectrograph 1991-1997 flights covering the spectral range 174-418 A and a temperature range from 80,000 K to 12.6 MK. This sample includes 248 lines from active regions, 101 lines from quiet-Sun regions, and 41 lines were observed from plasma off the solar limb. We find a strongly peaked distribution corresponding to a non-thermal velocity of 19-22 km s{sup -1} in all three of the quiet-Sun, active region, and off-limb distributions. For the possibility of Alfven wave resonance heating, we find that velocities in the core of these distributions do not provide sufficient energy, given typical densities and magnetic field strengths for the coronal plasma, to overcome the estimated coronal energy losses required to maintain the corona at the typical temperatures working as the sole mechanism. We find that at perfect efficiency 50%-60% of the needed energy flux can be produced from the non-thermal velocities measured.

Coyner, Aaron J. [Department of Physics, Catholic University of America, 620 Michigan Avenue, Washington, DC 20064 (United States); Davila, Joseph M., E-mail: aaron.j.coyner@nasa.gov [Code 671, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2011-12-01T23:59:59.000Z

294

Pump probe spectroscopy of quasiparticle dynamics in cuprate superconductors  

SciTech Connect (OSTI)

Pump probe spectroscopy is used to examine the picosecond response of a BSCCO thin film, and two YBCO crystals in the near infrared. The role of pump fluence and temperature have been closely examined in an effort to clarify the mechanism by which the quasiparticles rejoin the condensate. BSCCO results suggest that the recombination behavior is consistent with the d-wave density of states in that quasiparticles appear to relax to the nodes immediately before they rejoin the condensate. The first substantial investigation of polarized pump probe response in detwinned YBCO crystals is also reported. Dramatic doping dependent anisotropies along the a and b axes are observed in time and temperature resolved studies. Among many results, we highlight the discovery of an anomalous temperature and time dependence of a- axis response in optimally doped YBCO. We also report on the first observation of the photoinduced response in a magnetic field. We find the amplitude of the response, and in some cases, the dynamics considerably changed with the application of a 6T field. Finally, we speculate on two of the many theoretical directions stimulated by our results. We find that the two-fluid model suggests a mechanism to explain how changes at very low energies are visible to a high-energy probe. Also discussed are basic recombination processes which may play a role in the observed decay.

Segre, Gino P.

2001-05-01T23:59:59.000Z

295

Using neutral beams as a light ion beam probe (invited)  

SciTech Connect (OSTI)

By arranging the particle first banana orbits to pass near a distant detector, the light ion beam probe (LIBP) utilizes orbital deflection to probe internal fields and field fluctuations. The LIBP technique takes advantage of (1) the in situ, known source of fast ions created by beam-injected neutral particles that naturally ionize near the plasma edge and (2) various commonly available diagnostics as its detector. These born trapped particles can traverse the plasma core on their inner banana leg before returning to the plasma edge. Orbital displacements (the forces on fast ions) caused by internal instabilities or edge perturbing fields appear as modulated signal at an edge detector. Adjustments in the q-profile and plasma shape that determine the first orbit, as well as the relative position of the source and detector, enable studies under a wide variety of plasma conditions. This diagnostic technique can be used to probe the impact on fast ions of various instabilities, e.g., Alfvén eigenmodes (AEs) and neoclassical tearing modes, and of externally imposed 3D fields, e.g., magnetic perturbations. To date, displacements by AEs and by externally applied resonant magnetic perturbation fields have been measured using a fast ion loss detector. Comparisons with simulations are shown. In addition, nonlinear interactions between fast ions and independent AE waves are revealed by this technique.

Chen, Xi, E-mail: chenxi@fusion.gat.com [Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831 (United States); Heidbrink, W. W. [University of California Irvine, Irvine, California 92697 (United States); Van Zeeland, M. A.; Pace, D. C.; Petty, C. C.; Fisher, R. K. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Kramer, G. J.; Nazikian, R. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Austin, M. E. [University of Texas at Austin, Austin, Texas 78712 (United States); Hanson, J. M. [Columbia University, New York, New York 10027 (United States); Zeng, L. [University of California Los Angeles, Los Angeles, California 90095 (United States)

2014-11-15T23:59:59.000Z

296

Electromagnetic waves destabilized by runaway electrons in near-critical electric fields  

SciTech Connect (OSTI)

Runaway electron distributions are strongly anisotropic in velocity space. This anisotropy is a source of free energy that may destabilize electromagnetic waves through a resonant interaction between the waves and the energetic electrons. In this work, we investigate the high-frequency electromagnetic waves that are destabilized by runaway electron beams when the electric field is close to the critical field for runaway acceleration. Using a runaway electron distribution appropriate for the near-critical case, we calculate the linear instability growth rate of these waves and conclude that the obliquely propagating whistler waves are most unstable. We show that the frequencies, wave numbers, and propagation angles of the most unstable waves depend strongly on the magnetic field. Taking into account collisional and convective damping of the waves, we determine the number density of runaways that is required to destabilize the waves and show its parametric dependences.

Komar, A.; Pokol, G. I. [Department of Nuclear Techniques, Budapest University of Technology and Economics, Association EURATOM, H-1111 Budapest (Hungary); Fueloep, T. [Department of Applied Physics, Nuclear Engineering, Chalmers University of Technology and Euratom-VR Association, Goeteborg (Sweden)

2013-01-15T23:59:59.000Z

297

Downhole probes evaluate cavern integrity  

SciTech Connect (OSTI)

Obtaining natural-gas storage caverns` pressures and temperatures with downhole probes has allowed TransGas Ltd., Regina, to monitor and evaluate cavern integrity. TransGas has more than 5 years` experience with the devices. The acquired data have also helped determine gas-in-place inventory and confirm and assess changes in spatial volumes. These changes may have resulted from cavern creep (shrinkage or closure) or downhole abnormality such as fluid infill or collapse of the side walls or roof. This first of two articles presents background and many of the details and lessons to date of TransGas` cavern gas-storage probe program; the conclusion describes a specific storage site with some results.

Crossley, N.G. [TransGas Ltd., Regina, Saskatchewan (Canada)

1997-03-03T23:59:59.000Z

298

Wave turbulence served up on a plate  

E-Print Network [OSTI]

Wave turbulence in a thin elastic plate is experimentally investigated. By using a Fourier transform profilometry technique, the deformation field of the plate surface is measured simultaneously in time and space. This enables us to compute the wavevector-frequency Fourier ($\\mathbf k, \\omega$) spectrum of the full space-time deformation velocity. In the 3D ($\\mathbf k, \\omega$) space, we show that the energy of the motion is concentrated on a 2D surface that represents a nonlinear dispersion relation. This nonlinear dispersion relation is close to the linear dispersion relation. This validates the usual wavenumber-frequency change of variables used in many experimental studies of wave turbulence. The deviation from the linear dispersion, which increases with the input power of the forcing, is attributed to weak non linear effects. Our technique opens the way for many new extensive quantitative comparisons between theory and experiments of wave turbulence.

Pablo Cobelli; Philippe Petitjeans; Agnes Maurel; Vincent Pagneux; Nicolas Mordant

2009-10-28T23:59:59.000Z

299

Optical probe with reference fiber  

DOE Patents [OSTI]

A system for characterizing tissue includes the steps of generating an emission signal, generating a reference signal, directing the emission signal to and from the tissue, directing the reference signal in a predetermined manner relative to the emission signal, and using the reference signal to compensate the emission signal. In one embodiment compensation is provided for fluctuations in light delivery to the tip of the probe due to cable motion.

Da Silva, Luiz B. (Danville, CA); Chase, Charles L. (Dublin, CA)

2006-03-14T23:59:59.000Z

300

Water Waves Roger Grimshaw  

E-Print Network [OSTI]

,2) provide a kinematic description of water waves, which to this point means that the conditionsWater Waves Roger Grimshaw May 7, 2003 Abstract A short review of the theory of weakly nonlinear water waves, prepared for the forthcoming Encyclopedia of Nonlinear Science 1 Introduction Water waves

Note: This page contains sample records for the topic "velocity wave probe" 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

VELOCITY-SHEAR-INDUCED MODE COUPLING IN THE SOLAR ATMOSPHERE AND SOLAR WIND: IMPLICATIONS FOR PLASMA HEATING AND MHD TURBULENCE  

SciTech Connect (OSTI)

We analytically consider how velocity shear in the corona and solar wind can cause an initial Alfven wave to drive up other propagating signals. The process is similar to the familiar coupling into other modes induced by non-WKB refraction in an inhomogeneous plasma, except here the refraction is a consequence of velocity shear. We limit our discussion to a low-beta plasma, and ignore couplings into signals resembling the slow mode. If the initial Alfven wave is propagating nearly parallel to the background magnetic field, then the induced signals are mainly a forward-going (i.e., propagating in the same sense as the original Alfven wave) fast mode, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; both signals are compressive and subject to damping by the Landau resonance. For an initial Alfven wave propagating obliquely with respect to the magnetic field, the induced signals are mainly forward- and backward-going fast modes, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; these signals are all compressive and subject to damping by the Landau resonance. A backward-going Alfven wave, thought to be important in the development of MHD turbulence, is also produced, but it is very weak. However, we suggest that for oblique propagation of the initial Alfven wave the induced fast-polarized signal propagating like a forward-going Alfven wave may interact coherently with the initial Alfven wave and distort it at a strong-turbulence-like rate.

Hollweg, Joseph V.; Chandran, Benjamin D. G. [Space Science Center, Morse Hall, University of New Hampshire, Durham, NH 03824 (United States); Kaghashvili, Edisher Kh., E-mail: joe.hollweg@unh.edu, E-mail: ekaghash@aer.com, E-mail: benjamin.chandran@unh.edu [Atmospheric and Environmental Research, A Verisk Analytics Company, 131 Hartwell Avenue, Lexington, MA 02421 (United States)

2013-06-01T23:59:59.000Z

302

pH Meter probe assembly  

DOE Patents [OSTI]

An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe.

Hale, Charles J. (San Jose, CA)

1983-01-01T23:59:59.000Z

303

pH Meter probe assembly  

DOE Patents [OSTI]

An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe. 1 fig.

Hale, C.J.

1983-11-15T23:59:59.000Z

304

High-velocity clouds: a diverse phenomenon  

E-Print Network [OSTI]

In this contribution the current state of knowledge about the high-velocity clouds (HVCs) is summarized. Recent progress has shown that the HVCs are a diverse phenomenon. The intermediate-velocity clouds (IVCs) are likely to be part of a Galactic Fountain. The Magellanic Stream is a tidal remnant. HVC complex C (possibly complexes A and GCN) are low-metallicity clouds near the Galaxy; they could be remnants of the formation of the Galaxy or old tidal streams extracted from nearby dwarf galaxies. Having a substantial number of HI HVCs dispersed throughout the Local Group seems incompatible with the observed HI mass function of galaxies. Finally, FUSE finds high-velocity OVI, some of which is clearly associated with HI HVCs, but some which is not.

B. P. Wakker

2001-09-13T23:59:59.000Z

305

Lagrangian reconstruction of cosmic velocity fields  

E-Print Network [OSTI]

We discuss a Lagrangian reconstruction method of the velocity field from galaxy redshift catalog that takes its root in the Euler equation. This results in a ``functional'' of the velocity field which must be minimized. This is helped by an algorithm solving the minimization of cost-flow problems. The results obtained by applying this method to cosmological problems are shown and boundary effects happening in real observational cases are then discussed. Finally, a statistical model of the errors made by the reconstruction method is proposed.

G. Lavaux

2008-01-28T23:59:59.000Z

306

Sound velocity bound and neutron stars  

E-Print Network [OSTI]

It has been conjectured that the velocity of sound in any medium is smaller than the velocity of light in vacuum divided by $\\sqrt{3}$. Simple arguments support this bound in non-relativistic and/or weakly coupled theories. The bound has been demonstrated in several classes of strongly coupled theories with gravity duals and is saturated only in conformal theories. We point out that the existence of neutron stars with masses around two solar masses combined with the knowledge of the equation of state of hadronic matter at "low" densities is in strong tension with this bound.

Paulo F. Bedaque; Andrew W. Steiner

2015-01-25T23:59:59.000Z

307

Shell-instability generated waves by low energy electrons on converging magnetic field lines  

E-Print Network [OSTI]

Shell-instability generated waves by low energy electrons on converging magnetic field lines D of observations of such shell type distributions having positive slope in velocity space at low energies, about 10´cre´au (2006), Shell-instability generated waves by low energy electrons on converging magnetic field lines

California at Berkeley, University of

308

Cyclotron waves in a non-neutral plasma column Daniel H. E. Dubin  

E-Print Network [OSTI]

plasma column with near-Maxwellian velocity distributions. We focus on the z-independent component#12;Cyclotron waves in a non-neutral plasma column Daniel H. E. Dubin Department of Physics April 2013; published online 25 April 2013) A kinetic theory of linear electrostatic plasma waves

California at San Diego, University of

309

Two-dimensional elastic wave propagation in a duraluminum sheet  

E-Print Network [OSTI]

MENTAL PROCEDURE Experimental Design Data Acquisition Data Correction III. DATA PROCESSING 12 12 12 15 16 Wiener Filter Theory Construction of Desired. Wavelet 23 25 Wiener Filter Results 27 Bandpass Filter IV. TRAVELTIME ANALYSIS Wave... perpendicular to strike 2, Duraluminum model used in experiments 1 and 2 Relations between the Rayleigh-, P-, and S-wave velocities in an infinite medium for Poisson's ratio, o-, ranging from 0. 0 to 0. 5 Square root of energy ratios for reflected P- and S-waves...

Cefola, David Paul

1982-01-01T23:59:59.000Z

310

Electron Climbing a 'Devil's Staircase' in Wave-Particle Interaction  

SciTech Connect (OSTI)

Numerous nonlinear driven systems display spectacular responses to forcing, including chaos and complex phase-locking plateaus characterized by 'devil's staircase', Arnold tongues, and Farey trees. In the universality class of Hamiltonian systems, a paradigm is the motion of a charged particle in two waves, which inspired a renormalization group method for its description. Here we report the observation of the underlying 'devil's staircase' by recording the beam velocity distribution function at the outlet of a traveling wave tube versus the amplitude of two externally induced waves.

Macor, Alessandro; Doveil, Fabrice; Elskens, Yves [Physique des interactions ioniques et moleculaires, Unite 6633 CNRS-Universite de Provence, Equipe turbulence plasma, case 321, Centre de Saint-Jerome, F-13397 Marseille cedex 20 (France)

2005-12-31T23:59:59.000Z

311

Gravitational Waves in G4v  

E-Print Network [OSTI]

Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown to be highly distinguishable in the case of continuous gravitational-wave sources, and should therefore be testable as data from Advanced LIGO becomes available over the next few years.

Carver Mead

2015-03-16T23:59:59.000Z

312

the wave model A traveling wave is an organized disturbance  

E-Print Network [OSTI]

1 waves the wave model A traveling wave is an organized disturbance propagating at a well-defined wave speed v. · In transverse waves the particles of the medium move perpendicular to the direction of wave propagation. · In longitudinal waves the particles of the medium move parallel to the direction

Winokur, Michael

313

Gravitational Wave Sources from New Physics  

E-Print Network [OSTI]

Forthcoming advances in direct gravitational wave detection from kilohertz to nanohertz frequencies have unique capabilities to detect signatures from or set meaningful constraints on a wide range of new cosmological phenomena and new fundamental physics. A brief survey is presented of the post-inflationary gravitational radiation backgrounds predicted in cosmologies that include intense new classical sources such as first-order phase transitions, late-ending inflation, and dynamically active mesoscopic extra dimensions. LISA will provide the most sensitive direct probes of such phenomena near TeV energies or Terascale. LISA will also deeply probe the broadband background, and possibly bursts, from loops of cosmic superstrings predicted to form in current models of brane inflation.

Craig J. Hogan

2006-08-25T23:59:59.000Z

314

Lorentz violation and red shift of gravitational waves in brane-worlds  

E-Print Network [OSTI]

In this paper we study the speed of gravitational waves in a brane world scenario and show that if the extra dimension is space-like, the speed of the propagation of such waves is greater in the bulk than that on the brane. Therefore, the 4D Lorentz invariance is broken in the gravitational sector. A comparison is also made between the red shift of such waves and those of the electromagnetic waves on the brane. Such a comparison is essential for extracting the signature of the extra dimension and thus clarifying the question of maximal velocity of gravitational waves in the bulk.

Fatemeh Ahmadi; Jafar Khodagholizadeh; H. R. Sepangi

2014-11-07T23:59:59.000Z

315

PERFORMANCE EFFECTS OF AIR VELOCITY PROFILES IN  

E-Print Network [OSTI]

PERFORMANCE EFFECTS OF AIR VELOCITY PROFILES IN A RESIDENTIAL HEAT PUMP By NATHAN ANDREW WEBER PROFILES IN A RESIDENTIAL HEAT PUMP Thesis Approved: _______________________________________ Thesis Advisor the air speed transducer mount and the Plexiglas model of the heat pump. Ipseng Iu and myself worked side

316

Apparatus and method for laser velocity interferometry  

DOE Patents [OSTI]

An apparatus and method for laser velocity interferometry employing a fixed interferometer cavity and delay element. The invention permits rapid construction of interferometers that may be operated by those non-skilled in the art, that have high image quality with no drift or loss of contrast, and that have long-term stability even without shock isolation of the cavity.

Stanton, Philip L. (Bernalillo County, NM); Sweatt, William C. (Albuquerque, NM); Crump, Jr., O. B. (Albuquerque, NM); Bonzon, Lloyd L. (Albuquerque, NM)

1993-09-14T23:59:59.000Z

317

The propagation of waves in Einstein's unified field theory as shown by two exact solutions  

E-Print Network [OSTI]

The propagation of waves in two space dimensions exhibited by two exact solutions to the field equations of Einstein's unified field theory is investigated under the assumption that the metric s_{ik} is the one already chosen by Kursunoglu and by H\\'ely in the years 1952-1954. It is shown that, for both exact solutions, with this choice of the metric the propagation of the waves occurs in the wave zone with the fundamental velocity (ds^2=0).

Salvatore Antoci

2009-09-29T23:59:59.000Z

318

Imaging the lithosphere beneath NE Tibet: teleseismic P and S body wave tomography incorporating surface wave starting models  

E-Print Network [OSTI]

; Priestley&Tilmann 2009). In the absence of any prior information about the distribution of wave velocities in the crust, investigators generally use either station corrections de- rived from average residuals (e.g. Frederiksen et al. 1998; Graeber et al...

Nunn, Ceri; Roecker, Steven W.; Tilmann, Frederik J.; Priestley, Keith F.; Heyburn, Ross; Sandvol, Eric A.; Ni, James F.; Chen, Yongshun John; Zhao, Wenjin; INDEPTH IV Team

2013-12-24T23:59:59.000Z

319

Accessibility for lower hybrid waves in PBX-M  

SciTech Connect (OSTI)

Understanding the wave damping mechanism in the presence of a `spectral gap` is an important issue for the current profile control using Lower Hybrid Current Drive (LHCD). The authors examine a traditional explanation based upon upshifting of the wave parallel refractive index (n{sub {parallel}}) and find that there can be an upper bound in the n{sub {parallel}} upshift. The amount of upshift is not sufficient to bridge the spectral gap completely under some PBX-M LHCD conditions. There is experimental evidence, however, that current was driven even under such conditions. Another mechanism is also considered, based upon the 2-D velocity space dynamics coupled with a compound wave spectrum, here consisting of forward- and backward-running waves. The runaway critical speed relative to the phase speeds of these waves plays an important role in this model.

Takahashi, H.; Bell, R.; Bernabei, S.; Chance, M.; Chu, T.K.; Gettelfinger, G.; Greenough, N.; Hatcher, R.; Ignat, D.; Jardin, S.; Kaita, R.; Kaye, S.; Kugel, H.; LeBlanc, B.; Manickam, J.; Okabayashi, M.; Ono, M.; Paul, S.; Perkins, F.; Sauthoff, N.; Sesnic, S.; Sun, Y.; Tighe, W.; Valeo, E.; von Goeler, S. [Princeton Univ., NJ (US). Plasma Physics Lab.; Batha, S.; Levinton, F. [Fusion Physics and Technology, Torrance, CA (US); Dunlap, J.; England, A.; Harris, J.; Hirshman, S.; Isler, R.; Post-Zwicker, A. [Oak Ridge National Lab., TN (US); Jones, S.; Kesner, J.; Luckhardt, S.; Paoletti, F. [Massachusetts Inst. of Tech., Cambridge, MA (US); Schmitz, L.; Tynan, G. [Univ. of California, Los Angeles, CA (US)

1993-07-01T23:59:59.000Z

320

Surface electromagnetic wave equations in a warm magnetized quantum plasma  

SciTech Connect (OSTI)

Based on the single-fluid plasma model, a theoretical investigation of surface electromagnetic waves in a warm quantum magnetized inhomogeneous plasma is presented. The surface electromagnetic waves are assumed to propagate on the plane between a vacuum and a warm quantum magnetized plasma. The quantum magnetohydrodynamic model includes quantum diffraction effect (Bohm potential), and quantum statistical pressure is used to derive the new dispersion relation of surface electromagnetic waves. And the general dispersion relation is analyzed in some special cases of interest. It is shown that surface plasma oscillations can be propagated due to quantum effects, and the propagation velocity is enhanced. Furthermore, the external magnetic field has a significant effect on surface wave's dispersion equation. Our work should be of a useful tool for investigating the physical characteristic of surface waves and physical properties of the bounded quantum plasmas.

Li, Chunhua; Yang, Weihong [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Wu, Zhengwei, E-mail: wuzw@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Center of Low Temperature Plasma Application, Yunnan Aerospace Industry Company, Kunming, 650229 Yunnan (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2014-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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.


321

Interaction of two walkers: Wave-mediated energy and force  

E-Print Network [OSTI]

A bouncing droplet, self-propelled by its interaction with the waves it generates, forms a classical wave-particle association called a "walker." Previous works have demonstrated that the dynamics of a single walker is driven by its global surface wave field that retains information on its past trajectory. Here, we investigate the energy stored in this wave field for two coupled walkers and how it conveys an interaction between them. For this purpose, we characterize experimentally the "promenade modes" where two walkers are bound, and propagate together. Their possible binding distances take discrete values, and the velocity of the pair depends on their mutual binding. The mean parallel motion can be either rectilinear or oscillating. The experimental results are recovered analytically with a simple theoretical framework. A relation between the kinetic energy of the droplets and the total energy of the standing waves is established.

Borghesi, Christian; Labousse, Matthieu; Eddi, Antonin; Fort, Emmanuel; Couder, Yves

2014-01-01T23:59:59.000Z

322

Ion-beam driven lower hybrid waves in a magnetized dusty plasma  

SciTech Connect (OSTI)

An ion beam drives lower hybrid waves to instability in a magnetized dusty plasma via Cerenkov interaction. A dispersion relation and the growth rate of the lower hybrid waves have been derived taking into account the dust charge fluctuations. The frequency and the growth rate of the unstable wave instability increase with relative density of negatively charged dust grains. The lower hybrid modes with phase velocity comparable to the beam velocity possess a large growth rate. Moreover, the growth rate of the instability increases with beam density and scales as the one-third power of the beam density.

Prakash, Ved; Vijayshri [School of Sciences, Indira Gandhi National Open University, Maidan Garhi, New Delhi 110 068 (India)] [School of Sciences, Indira Gandhi National Open University, Maidan Garhi, New Delhi 110 068 (India); Sharma, Suresh C. [Department of Applied Physics, Delhi Technological University, Shahbad Daulatpur, Bawana Road, Delhi 110 042 (India)] [Department of Applied Physics, Delhi Technological University, Shahbad Daulatpur, Bawana Road, Delhi 110 042 (India); Gupta, Ruby [Department of Physics, Swami Shraddhanand College, University of Delhi, Alipur, Delhi 110 036 (India)] [Department of Physics, Swami Shraddhanand College, University of Delhi, Alipur, Delhi 110 036 (India)

2013-06-15T23:59:59.000Z

323

Photon wave function  

E-Print Network [OSTI]

Photon wave function is a controversial concept. Controversies stem from the fact that photon wave functions can not have all the properties of the Schroedinger wave functions of nonrelativistic wave mechanics. Insistence on those properties that, owing to peculiarities of photon dynamics, cannot be rendered, led some physicists to the extreme opinion that the photon wave function does not exist. I reject such a fundamentalist point of view in favor of a more pragmatic approach. In my view, the photon wave function exists as long as it can be precisely defined and made useful.

Iwo Bialynicki-Birula

2005-08-26T23:59:59.000Z

324

Observation of negative-frequency waves in a water tank: A classical analogue to the Hawking effect?  

E-Print Network [OSTI]

The conversion of positive-frequency waves into negative-frequency waves at the event horizon is the mechanism at the heart of the Hawking radiation of black holes. In black-hole analogues, horizons are formed for waves propagating in a medium against the current when and where the flow exceeds the wave velocity. We report on the first direct observation of negative-frequency waves converted from positive-frequency waves in a moving medium. The measured degree of mode conversion is significantly higher than expected from theory.

Germain Rousseaux; Christian Mathis; Philippe Maissa; Thomas G. Philbin; Ulf Leonhardt

2008-03-01T23:59:59.000Z

325

Nonlinear Hydromagnetic Wave Support of a Stratified Molecular Cloud  

E-Print Network [OSTI]

We perform numerical simulations of nonlinear MHD waves in a gravitationally stratified molecular cloud that is bounded by a hot and tenuous external medium. We study the relation between the strength of the turbulence and various global properties of a molecular cloud, within a 1.5-dimensional approximation. Under the influence of a driving source of Alfvenic disturbances, the cloud is lifted up by the pressure of MHD waves and reaches a steady-state characterized by oscillations about a new time-averaged equilibrium state. The nonlinear effect results in the generation of longitudinal motions and many shock waves; however, the wave kinetic energy remains predominantly in transverse, rather than longitudinal, motions. There is an approximate equipartition of energy between the transverse velocity and fluctuating magnetic field (aspredicted by small-amplitude theory) in the region of the stratified cloud which contains most of the mass; however, this relation breaks down in the outer regions, particularly near the cloud surface, where the motions have a standing-wave character. This means that the Chandrasekhar-Fermi formula applied to molecular clouds must be significantly modified in such regions. Models of an ensemble of clouds show that, for various strengths of the input energy, the velocity dispersion in the cloud $\\sigma \\propto Z^{0.5}$, where $Z$ is a characteristic size of the cloud.Furthermore, $\\sigma$ is always comparable to the mean Alfven velocity of the cloud, consistent with observational results.

T. Kudoh; S. Basu

2003-06-23T23:59:59.000Z

326

Turbulence Spectra from Spectral Lines: Tests of the Velocity Channel Analysis and Velocity Coordinate Spectrum Techniques  

E-Print Network [OSTI]

Turbulence is a key element of the dynamics of astrophysical fluids, including those of interstellar medium, clusters of galaxies and circumstellar regions. Turbulent motions induce Doppler shifts of observable emission and absorption lines and this motivates studies of turbulence using precision spectroscopy. We provide high resolution numerical testing of the two promising techniques, namely, Velocity Channel Analysis and Velocity Coordinate Spectrum. We obtain an expression for the shot noise that the discretization of the numerical data entails and successfully test it. We show that numerical resolution required for recovering the underlying turbulent spectrum from observations depend on the spectral index of velocity fluctuations. Thus the low resolution testing may be misleading.

A. Chepurnov; A. Lazarian

2007-01-31T23:59:59.000Z

327

Stochastic background of gravitational waves from cosmological sources  

E-Print Network [OSTI]

Gravitational waves (GW) can constitute a unique probe of the primordial universe. In many cases, the characteristic frequency of the emitted GW is directly related to the energy scale at which the GW source is operating in the early universe. Consequently, different GW detectors can probe different energy scales in the evolution of the universe. After a general introduction on the properties of a GW stochastic background of primordial origin, some examples of cosmological sources are presented, which may lead to observable GW signals.

Caprini, Chiara

2015-01-01T23:59:59.000Z

328

Entangled quantum probes for dynamical environmental noise  

E-Print Network [OSTI]

We address the use of entangled qubits as quantum probes to characterize the dynamical noise induced by complex environments. In particular, we show that entangled probes improve estimation of the correlation time for a broad class of environmental noises compared to any sequential strategy involving single qubit preparation. The effect is present when the noise is faster than a threshold value, a regime which may always be achieved by tuning the coupling between the quantum probe and the environment inducing the noise. Our scheme exploits time-dependent sensitivity of quantum systems to decoherence and does not require dynamical control on the probes. We derive the optimal interaction time and the optimal probe preparation, showing that it corresponds to multiqubit GHZ states when entanglement is useful. We also show robustness of the scheme against depolarization or dephasing of the probe, and discuss simple measurements approaching optimal precision.

Matteo A. C. Rossi; Matteo G. A. Paris

2015-03-11T23:59:59.000Z

329

Wave-induced chaos in a continuously fed unstirred reactor John H. Merkin,"Valery Petrov,bStephen K. Scottc*and Kenneth Showalterb  

E-Print Network [OSTI]

Wave-induced chaos in a continuously fed unstirred reactor John H. Merkin,"Valery Petrov,bStephen K of a constant-velocity constant-form reaction wave that traverses the reaction domain, leaving behind, allowing further wave events to be initiated, which then propagate into the `recovered' region. The chaotic

Showalter, Kenneth

330

Tunable nanowire nonlinear optical probe  

SciTech Connect (OSTI)

One crucial challenge for subwavelength optics has been thedevelopment of a tunable source of coherent laser radiation for use inthe physical, information, and biological sciences that is stable at roomtemperature and physiological conditions. Current advanced near-fieldimaging techniques using fiber-optic scattering probes1,2 have alreadyachieved spatial resolution down to the 20-nm range. Recently reportedfar-field approaches for optical microscopy, including stimulatedemission depletion (STED)3, structured illumination4, and photoactivatedlocalization microscopy (PALM)5, have also enabled impressive,theoretically-unlimited spatial resolution of fluorescent biomolecularcomplexes. Previous work with laser tweezers6-8 has suggested the promiseof using optical traps to create novel spatial probes and sensors.Inorganic nanowires have diameters substantially below the wavelength ofvisible light and have unique electronic and optical properties9,10 thatmake them prime candidates for subwavelength laser and imagingtechnology. Here we report the development of an electrode-free,continuously-tunable coherent visible light source compatible withphysiological environments, from individual potassium niobate (KNbO3)nanowires. These wires exhibit efficient second harmonic generation(SHG), and act as frequency converters, allowing the local synthesis of awide range of colors via sum and difference frequency generation (SFG,DFG). We use this tunable nanometric light source to implement a novelform of subwavelength microscopy, in which an infrared (IR) laser is usedto optically trap and scan a nanowire over a sample, suggesting a widerange of potential applications in physics, chemistry, materials science,and biology.

Nakayama, Yuri; Pauzauskie, Peter J.; Radenovic, Aleksandra; Onorato, Robert M.; Saykally, Richard J.; Liphardt, Jan; Yang, Peidong

2008-02-18T23:59:59.000Z

331

3D REGULARIZED VELOCITY FROM 3D DOPPLER RADIAL VELOCITY X. Chen, J.L. Barron, R.E. Mercer  

E-Print Network [OSTI]

3D REGULARIZED VELOCITY FROM 3D DOPPLER RADIAL VELOCITY X. Chen, J.L. Barron, R.E. Mercer Dept, Ontario, M3H 5T4 Paul.Joe@ec.gc.ca ABSTRACT The recent availability of sequences of 3D Doppler radial velocity datasets provides sufficient information to estimate the 3D velocity of Doppler storms. We present

Barron, John

332

Laboratory measurements of the temporal and cross-shore variation of the wave-induced bed stress  

E-Print Network [OSTI]

Detailed laboratory measurements of horizontal velocity above a rough, fixed, impermeable slope were made to determine the effect of varying wave conditions on the shear stress in the swash zone. The research involved the design, construction...

Sukumaran, Ashok

2000-01-01T23:59:59.000Z

333

AN EXTREME-ULTRAVIOLET WAVE ASSOCIATED WITH A SURGE  

SciTech Connect (OSTI)

Taking advantage of the high temporal and spatial resolution observations from the Solar Dynamics Observatory, we present an extreme-ultraviolet (EUV) wave associated with a surge on 2010 November 13. Due to the magnetic flux cancelation, some surges formed in the source active region (AR). The strongest surge produced our studied event. The surge was deflected by the nearby loops that connected to another AR, and disrupted the overlying loops that slowly expanded and eventually evolved into a weak coronal mass ejection (CME). The surge was likely associated with the core of the CME. The EUV wave happened after the surge deflected. The wave departed far from the flare center and showed a close location relative to the deflected surge. The wave propagated in a narrow angular extent, mainly in the ejection direction of the surge. The close timing and location relations between the EUV wave and the surge indicate that the wave was closely associated with the CME. The wave had a velocity of 310-350 km s{sup -1}, while the speeds of the surge and the expanding loops were about 130 and 150 km s{sup -1}, respectively. All of the results suggest that the EUV wave was a fast-mode wave and was most likely triggered by the weak CME.

Zheng, Ruisheng; Jiang, Yunchun; Yang, Jiayan; Bi, Yi; Hong, Junchao; Yang, Bo; Yang, Dan, E-mail: zhrsh@ynao.ac.cn [National Astronomical Observatories/Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)] [National Astronomical Observatories/Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011 (China)

2013-02-10T23:59:59.000Z

334

Penetration of lower hybrid current drive waves in tokamaks  

SciTech Connect (OSTI)

Lower hybrid (LH) ray propagation in toroidal plasma is shown to be controlled by combination of the azimuthal spectrum launched by the antenna, the poloidal variation of the magnetic field, and the scattering of the waves by the drift wave fluctuations. The width of the poloidal and radial radio frequency wave spectrum increases rapidly as the rays penetrate into higher density and scatter from the drift waves. The electron temperature gradient (ETG) spectrum is particularly effective in scattering the LH waves due to its comparable wavelengths and phase velocities. ETG turbulence is also driven by the radial gradient of the electron current profile giving rise to an anomalous viscosity spreading the LH driven plasma currents. The LH wave scattering is derived from a Fokker-Planck equation for the distribution of the ray trajectories with diffusivities derived from the drift wave fluctuations. The condition for chaotic diffusion for the rays is derived. The evolution of the poloidal and radial mode number spectrum of the lower hybrid waves are both on the antenna spectrum and the spectrum of the drift waves. Antennas launching higher poloidal mode number spectra drive off-axis current density profiles producing negative central shear [RS] plasmas with improved thermal confinement from ETG transport. Core plasma current drive requires antennas with low azimuthal mode spectra peaked at m = 0 azimuthal mode numbers.

Horton, W. [The University of Texas at Austin, Austin, Texas 78712 (United States) [The University of Texas at Austin, Austin, Texas 78712 (United States); Aix-Marseille University, 58, Bd Charles Livon, 13284 Marseille (France); Goniche, M.; Peysson, Y.; Decker, J.; Ekedahl, A.; Litaudon, X. [CEA, IRFM, F-13108 Saint-Paul-Lez Durance (France)] [CEA, IRFM, F-13108 Saint-Paul-Lez Durance (France)

2013-11-15T23:59:59.000Z

335

Propagating and reflecting of spin wave in permalloy nanostrip with 360° domain wall  

SciTech Connect (OSTI)

By micromagnetic simulation, we investigated the interaction between propagating spin wave (or magnonic) and a 360° domain wall in a nanostrip. It is found that propagating spin wave can drive a 360° domain wall motion, and the velocity and direction are closely related to the transmission coefficient of the spin wave of the domain wall. When the spin wave passes through the domain wall completely, the 360° domain wall moves toward the spin wave source. When the spin wave is reflected by the domain wall, the 360° domain wall moves along the spin wave propagation direction. Moreover, when the frequency of the spin wave is coincident with that of the 360° domain wall normal mode, the 360° domain wall velocity will be resonantly enhanced no matter which direction the 360 DW moves along. On the other hand, when the spin wave is reflected from the moving 360° domain wall, we observed the Doppler effect clearly. After passing through a 360° domain wall, the phase of the spin wave is changed, and the phase shift is related to the frequency. Nevertheless, phase shift could be manipulated by the number of 360° domain walls that spin wave passing through.

Zhang, Senfu; Mu, Congpu; Zhu, Qiyuan; Zheng, Qi; Liu, Xianyin; Wang, Jianbo; Liu, Qingfang, E-mail: liuqf@lzu.edu.cn [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

2014-01-07T23:59:59.000Z

336

New wave generation  

E-Print Network [OSTI]

We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (Exp. Fluids, vol. 42, 2007, pp. 123–130). This ...

Mercier, Matthieu J.

337

Probing Organic Transistors with Infrared Beams  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Probing Organic Transistors with Infrared Beams Print Silicon-based transistors are well-understood, basic components of contemporary electronic technology. In contrast, there is...

338

PROBING DENSE NUCLEAR MATTER VIA NUCLEAR COLLISIONS  

E-Print Network [OSTI]

University of California. LBL-12095 Probing Dense NuclearMatter Nuclear Collisions* v~a H. Stocker, M.Gyulassy and J. Boguta Nuclear Science Division Lawrence

Stocker, H.

2012-01-01T23:59:59.000Z

339

Velocity coordinate spectrum: geometrical aspects of observations  

E-Print Network [OSTI]

We analyze a technique of obtaining turbulence power spectrum using spectral line data along the velocity coordinate, which we refer to as Velocity Coordinate Spectrum (VCS). We formalize geometrical aspects of observation through a single factor, "geometric term". We find that all variety of particular observational configurations can be described using correspondent variants of this term, which we explicitly calculate. This allows us to obtain asymptotics for both parallel lines of sight and crossing lines of sight. The latter case is especially important for studies of turbulence within diffuse ISM in Milky Way. For verification of our results, we use direct calculation of VCS spectra, while the numerical simulations are presented in a companion paper.

A. Chepurnov; A. Lazarian

2007-01-31T23:59:59.000Z

340

Solids Fraction Measurement with a Reflective Fiber Optic Probe  

SciTech Connect (OSTI)

A method has been developed to extract solids fraction information from a reflective fiber optic probe. The commercially available reflective fiber optic probe was designed to measure axial particle velocity (both up and down directions). However, the reflected light intensity measured is related to particle size and particle concentration. A light reflection model is used to relate the reflected light intensity to solids fraction. In this model we assume that the reflected light intensity is a fixed fraction, K1, of the total light intensity lost in penetration of a solid layer. Also, the solids fraction is related to particle concentration, N, in the light path, by N = K2 (1- ?), where (1-?) is the solids fraction. The parameters K1 and K2 are determined through a calibration and curve fitting procedure. This paper describes this procedure and the steps taken to derive the values of K1 and K2. It is proposed that the reflective fiber optic can be used for real time measurement of solids fraction in a circulating fluid bed.

Seachman, S.M.; Yue, P.C.; Ludlow, J.C.; Shadle, L.J.

2006-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Terahertz imaging of sub-wavelength particles with Zenneck surface waves  

SciTech Connect (OSTI)

Impact of sub-wavelength-size dielectric particles on Zenneck surface waves on planar metallic antennas is investigated at terahertz (THz) frequencies with THz near-field probe microscopy. Perturbations of the surface waves show the particle presence, despite its sub-wavelength size. The experimental configuration, which utilizes excitation of surface waves at metallic edges, is suitable for THz imaging of dielectric sub-wavelength size objects. As a proof of concept, the effects of a small strontium titanate rectangular particle and a titanium dioxide sphere on the surface field of a bow-tie antenna are experimentally detected and verified using full-wave simulations.

Navarro-Cía, M., E-mail: m.navarro@imperial.ac.uk [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2BT (United Kingdom); Centre for Plasmonics and Metamaterials, Imperial College London, London SW7 2AZ (United Kingdom); Centre for Terahertz Science and Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Natrella, M.; Graham, C.; Renaud, C. C.; Seeds, A. J.; Mitrofanov, O., E-mail: o.mitrofanov@ucl.ac.uk [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Dominec, F.; Kužel, P., E-mail: kuzelp@fzu.cz [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Delagnes, J. C.; Mounaix, P., E-mail: p.mounaix@loma.u-bordeaux1.fr [LOMA, Bordeaux 1 University, CNRS UMR 4798, 351 cours de la Libération, 33405 Talence (France)

2013-11-25T23:59:59.000Z

342

Covariant nucleon wave function with S, D, and P-state components  

SciTech Connect (OSTI)

Expressions for the nucleon wave functions in the covariant spectator theory (CST) are derived. The nucleon is described as a system with a off-mass-shell constituent quark, free to interact with an external probe, and two spectator constituent quarks on their mass shell. Integrating over the internal momentum of the on-mass-shell quark pair allows us to derive an effective nucleon wave function that can be written only in terms of the quark and diquark (quark-pair) variables. The derived nucleon wave function includes contributions from S, P and D-waves.

Franz Gross, G. Ramalho, M. T. Pena

2012-05-01T23:59:59.000Z

343

"Nonrelativistic" kinematics: Particles or waves?  

E-Print Network [OSTI]

The kinematics of particles refer to events and tangent vectors, while that of waves refer to dual gradient planes. Special relativity [1-3] applies to both objects alike. Here we show that spacetime exchange symmetry [7] implicit in the SIdefinition of length based on the universal constant c has profound consequences at low velocities. Galilean physics, exact in the limit c \\to \\infty, is mirrored by a dual so-called Carrollian superluminal kinematics [4-6] exact in the limit c \\to 0. Several new results follow. The Galilean limit explains mass conservation in Newtonian mechanics, while the dual limit is a kinematical prerequisite for wavelike tachyonic motion [8, 9]. As an example, the Land\\'e paradox [19, 20] of waveparticle duality has a natural resolution within special relativity in terms of superluminal, particlelike waves. It is emphasized that internal particle energy mc^2 can not be ignored, while kinetic energy leads to an extended Galilei group. We also demonstrate that Maxwell's equations have magnetic and electric limits covariant under Galilean and Carrollian symmetry.

Jens Madsen Houlrik; Germain Rousseaux

2010-05-11T23:59:59.000Z

344

Wave fronts, pulses and wave trains in photoexcited superlattices behaving as excitable or oscillatory media  

E-Print Network [OSTI]

Undoped and strongly photoexcited semiconductor superlattices with field-dependent recombination behave as excitable or oscillatory media with spatially discrete nonlinear convection and diffusion. Infinitely long, dc-current-biased superlattices behaving as excitable media exhibit wave fronts with increasing or decreasing profiles, whose velocities can be calculated by means of asymptotic methods. These superlattices can also support pulses of the electric field. Pulses moving downstream with the flux of electrons can be constructed from their component wave fronts, whereas pulses advancing upstream do so slowly and experience saltatory motion: they change slowly in long intervals of time separated by fast transitions during which the pulses jump to the previous superlattice period. Photoexcited superlattices can also behave as oscillatory media and exhibit wave trains.

J. I. Arana; L. L. Bonilla; H. T. Grahn

2011-09-30T23:59:59.000Z

345

Heating of ions by high frequency electromagnetic waves in magnetized plasmas  

SciTech Connect (OSTI)

The heating of ions by high frequency electrostatic waves in magnetically confined plasmas has been a paradigm for studying nonlinear wave-particle interactions. The frequency of the waves is assumed to be much higher than the ion cyclotron frequency and the waves are taken to propagate across the magnetic field. In fusion type plasmas, electrostatic waves, like the lower hybrid wave, cannot access the core of the plasma. That is a domain for high harmonic fast waves or electron cyclotron waves—these are primarily electromagnetic waves. Previous studies on heating of ions by two or more electrostatic waves are extended to two electromagnetic waves that propagate directly across the confining magnetic field. While the ratio of the frequency of each wave to the ion cyclotron frequency is large, the frequency difference is assumed to be near the ion cyclotron frequency. The nonlinear wave-particle interaction is studied analytically using a two time-scale canonical perturbation theory. The theory elucidates the effects of various parameters on the gain in energy by the ions—parameters such as the amplitudes and polarizations of the waves, the ratio of the wave frequencies to the cyclotron frequency, the difference in the frequency of the two waves, and the wave numbers associated with the waves. For example, the ratio of the phase velocity of the envelope formed by the two waves to the phase velocity of the carrier wave is important for energization of ions. For a positive ratio, the energy range is much larger than for a negative ratio. So waves like the lower hybrid waves will impart very little energy to ions. The theoretical results are found to be in good agreement with numerical simulations of the exact dynamical equations. The analytical results are used to construct mapping equations, simplifying the derivation of the motion of ions, which are, subsequently, used to follow the evolution of an ion distribution function. The heating of ions can then be properly quantified in terms of the wave parameters and can be conveniently used to find ideal conditions needed to heat ions by high frequency electromagnetic waves.

Zestanakis, P. A.; Kominis, Y.; Hizanidis, K. [School of Electrical and Computer Engineering, National Technical University of Athens, Association EURATOM-Hellenic Republic, Zographou GR-15773 (Greece)] [School of Electrical and Computer Engineering, National Technical University of Athens, Association EURATOM-Hellenic Republic, Zographou GR-15773 (Greece); Ram, A. K. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2013-07-15T23:59:59.000Z

346

Interpreting Velocities from Heat-Based Flow Sensors by NumericalSimulation  

SciTech Connect (OSTI)

We have carried out numerical simulations of three-dimensional non-isothermal flow around an in situ heat-based flow sensor to investigate how formation heterogeneities can affect the interpretation of ground water flow velocities from this instrument. The flow sensor operates by constant heating of a 0.75 m long, 5 cm diameter cylindrical probe, which contains 30 thermistors in contact with the formation. The temperature evolution at each thermistor can be inverted to obtain an estimate of the ground water flow velocity vector using the standard interpretive method, which assumes that the formation is homogeneous. Analysis of data from heat-based flow sensors installed in a sand aquifer at the Former Fort Ord Army Base near Monterey, California suggested an unexpected component of downward flow. The magnitudes of the vertical velocities were expected to be much less than the horizontal velocities at this site because the sensors were installed just above a clay aquitard. Numerical simulations were conducted to examine how differences in thermal conductivities may lead to spurious indications of vertical flow velocities. We found that a decrease in the thermal conductivity near the bottom of the sensor can perturb the temperature profiles along the instrument in such a manner that analyses assuming homogeneous thermal conductivity could indicate a vertical flow component even though flow is actually horizontal. This work demonstrates how modeling can be used to simulate instrument response to formation heterogeneity, and shows that caution must be used in interpreting data from such devices using overly simplistic assumptions.

Su, Grace W.; Freifeld, Barry M.; Oldenburg, Curtis M.; Jordan,Preston D.; Daley, Paul F.

2005-06-13T23:59:59.000Z

347

Effects of quintessence on holographic p-wave superconductors  

E-Print Network [OSTI]

We construct a holographic p-wave superconductor model in the background of quintessence AdS black hole with an SU(2) Yang-Mills gauge field and then probe the effects of quintessence on the holographic p-wave superconductor. We investigate the relation between the critical temperature and the state parameter of quintessence, and present the numerical results for electric conductivity. It is shown that the condensation of the vector field becomes harder as the absolute value of the state parameter increases. Unlike the scalar condensate in the s-wave model, the condensation of the vector field in p-wave model can occur in the total value range of the state parameter $w_q$ of quintessence. These results could help us know more about holographic superconductor and dark energy.

Songbai Chen; Qiyuan Pan; Jiliang Jing

2012-06-24T23:59:59.000Z

348

Performance Assessment of the Wave Dragon Wave Energy Converter  

E-Print Network [OSTI]

Performance Assessment of the Wave Dragon Wave Energy Converter Based on the EquiMar Methodology S of the wave energy sector, device developers are called to provide reliable estimates on power performanceMar, Nissum Bredning, Hanstholm, North Sea, Ekofisk, Wave-to-wire, Wave energy. I. INTRODUCTION The wave

Hansen, René Rydhof

349

Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino  

E-Print Network [OSTI]

Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino Department of Physics and Astronomy with their announcement that: "We find that a new type of sound wave, namely, the dust-acoustic waves, can appear" [1 and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some

Merlino, Robert L.

350

Comparing the performance of plasma impedance probes and Langmuir probes for RF plasma diagnostics  

E-Print Network [OSTI]

Comparing the performance of plasma impedance probes and Langmuir probes for RF plasma diagnostics probing, a less developed technique, can possibly overcome these problems. Better plasma diagnostic tools Ethan Dale, Dr. Mitchell Walker High-Power Electric Propulsion Laboratory Objective Plasma is the most

Walker, Mitchell

351

MERIT Pump/Probe Data OutlineOutline  

E-Print Network [OSTI]

MERIT Pump/Probe Data Analysis OutlineOutline The pump/probe program Particle detector response correction Pump/probe analysis results NFMCC Collaboration Meeting , LBNL, January 26, 2009 Ilias Efthymiopoulos - CERN #12;The pump/probe program #12;The pump/probe program Use of the CERN PS flexibility

McDonald, Kirk

352

Scanning Probe Microscopy Studies of Carbon Nanotubes  

E-Print Network [OSTI]

Scanning Probe Microscopy Studies of Carbon Nanotubes Teri Wang Odom1 , Jason H. Hafner1 relationship between Single-Walled Carbon Nanotube (SWNT) atomic structure and electronic properties, (2, properties and application of carbon nanotube probe microscopy tips to ultrahigh resolution and chemically

Odom, Teri W.

353

Nonlinear theory of ionic sound waves in a hot quantum-degenerate electron-positron-ion plasma  

SciTech Connect (OSTI)

A collisionless nonmagnetized e-p-i plasma consisting of quantum-degenerate gases of ions, electrons, and positrons at nonzero temperatures is considered. The dispersion equation for isothermal ionic sound waves is derived and analyzed, and an exact expression is obtained for the linear velocity of ionic sound. Analysis of the dispersion equation has made it possible to determine the ranges of parameters in which nonlinear solutions in the form of solitons should be sought. A nonlinear theory of isothermal ionic sound waves is developed and used for obtaining and analyzing the exact solution to the system of initial equations. Analysis has been carried out by the method of the Bernoulli pseudopotential. The ranges of phase velocities of periodic ionic sound waves and soliton velocities are determined. It is shown that in the plasma under investigation, these ranges do not overlap and that the soliton velocity cannot be lower than the linear velocity of ionic sound. The profiles of physical quantities in a periodic wave and in a soliton are constructed, as well as the dependences of the velocity of sound and the critical velocity on the ionic concentration in the plasma. It is shown that these velocities increase with the ion concentration.

Dubinov, A. E., E-mail: dubinov-ae@yandex.ru; Sazonkin, M. A., E-mail: figma@mail.r [Sarov State Physicotechnical Institute (Russian Federation)

2010-11-15T23:59:59.000Z

354

Ultraslow propagation of matched pulses by four-wave mixing in an atomic vapor  

E-Print Network [OSTI]

We have observed the ultraslow propagation of matched pulses in nondegenerate four-wave mixing in a hot atomic vapor. Probe pulses as short as 70 ns can be delayed by a tunable time of up to 40 ns with little broadening or distortion. During the propagation, a probe pulse is amplified and generates a conjugate pulse which is faster and separates from the probe pulse before getting locked to it at a fixed delay. The precise timing of this process allows us to determine the key coefficients of the susceptibility tensor. The presence of gain in this system makes this system very interesting in the context of all-optical information processing.

V. Boyer; C. F. McCormick; E. Arimondo; P. D. Lett

2007-03-19T23:59:59.000Z

355

Rugged fiber optic probe for raman measurement  

DOE Patents [OSTI]

An optical probe for conducting light scattering analysis is disclosed. The probe comprises a hollow housing and a probe tip. A fiber assembly made up of a transmitting fiber and a receiving bundle is inserted in the tip. A filter assembly is inserted in the housing and connected to the fiber assembly. A signal line from the light source and to the spectrometer also is connected to the filter assembly and communicates with the fiber assembly. By using a spring-loaded assembly to hold the fiber connectors together with the in-line filters, complex and sensitive alignment procedures are avoided. The close proximity of the filter assembly to the probe tip eliminates or minimizes self-scattering generated by the optical fiber. Also, because the probe can contact the sample directly, sensitive optics can be eliminated.

O'Rourke, Patrick E. (Martinez, GA); Toole, Jr., William R. (Aiken, SC); Nave, Stanley E. (Evans, GA)

1998-01-01T23:59:59.000Z

356

Individual quantum probes for optimal thermometry  

E-Print Network [OSTI]

The unknown temperature of a sample may be estimated with minimal disturbance by putting it in thermal contact with an individual quantum probe. If the interaction time is sufficiently long so that the probe thermalizes, the temperature can be read out directly from its steady state. Here we prove that the optimal quantum probe, acting as a thermometer with maximal thermal sensitivity, is an effective two-level atom with a maximally degenerate excited state. When the total interaction time is insufficient to produce full thermalization, we optimize the estimation protocol by breaking it down into sequential stages of probe preparation, thermal contact and measurement. We observe that frequently interrogated probes initialized in the ground state achieve the best performance. For both fully and partly thermalized thermometers, the sensitivity grows significantly with the number of levels, though optimization over their energy spectrum remains always crucial.

Luis A. Correa; Mohammad Mehboudi; Gerardo Adesso; Anna Sanpera

2014-11-23T23:59:59.000Z

357

Anisotropic wave propagation in nematic liquid crystals  

E-Print Network [OSTI]

Despite the fact that quantitative experimental data have been available for more than forty years now, nematoacoustics still poses intriguing theoretical and experimental problems. In this paper, we prove that the main observed features of acoustic wave propagation through a nematic liquid crystal cell -- namely, the anisotropy of sound velocity and its frequency dependence -- may be plausibly explained by a first-gradient continuum theory characterized by a hyperelastic anisotropic response from an evolving relaxed configuration. We compare and contrast our proposal with a competing theory where the liquid crystal is modeled as an isotropically compressible, anisotropic second-gradient fluid.

Paolo Biscari; Antonio DiCarlo; Stefano S. Turzi

2014-05-10T23:59:59.000Z

358

On the Velocity and Intensity Line Asymmetries  

E-Print Network [OSTI]

We show that, if solar 5 min. oscillations are excited by convection in the upper layers of the convective envelope, it is impossible to explain the opposite line asymmetries observed in the velocity and intensity spectra with assumptions on the dissipations which reduce the problem to a second order one. The interpretation of that observation requires to solve the full non-adiabatic problem which is of the fourth or sixth order. We also analyze the causes of line asymmetries in the frame of the general problem and we show that to locate the source, it is better to study line asymmetries not too far from line centers.

M. Gabriel

1997-10-01T23:59:59.000Z

359

A comparison between matter wave and light wave interferometers for the detection of gravitational waves  

E-Print Network [OSTI]

We calculate and compare the response of light wave interferometers and matter wave interferometers to gravitational waves. We find that metric matter wave interferometers will not challenge kilometric light wave interferometers such as Virgo or LIGO, but could be a good candidate for the detection of very low frequency gravitational waves.

Pacôme Delva; Marie-Christine Angonin; Philippe Tourrenc

2006-09-20T23:59:59.000Z

360

MAGNETOHYDRODYNAMIC SHALLOW WATER WAVES: LINEAR ANALYSIS  

SciTech Connect (OSTI)

We present a linear analysis of inviscid, incompressible, magnetohydrodynamic (MHD) shallow water systems. In spherical geometry, a generic property of such systems is the existence of five wave modes. Three of them (two magneto-Poincare modes and one magneto-Rossby mode) are previously known. The other two wave modes are strongly influenced by the magnetic field and rotation, and have substantially lower angular frequencies; as such, we term them 'magnetostrophic modes'. We obtain analytical functions for the velocity, height, and magnetic field perturbations in the limit that the magnitude of the MHD analogue of Lamb's parameter is large. On a sphere, the magnetostrophic modes reside near the poles, while the other modes are equatorially confined. Magnetostrophic modes may be an ingredient in explaining the frequency drifts observed in Type I X-ray bursts from neutron stars.

Heng, Kevin [Institute for Advanced Study, School of Natural Sciences, Einstein Drive, Princeton, NJ 08540 (United States); Spitkovsky, Anatoly, E-mail: heng@ias.ed, E-mail: anatoly@astro.princeton.ed [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States)

2009-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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.
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361

Sound Wave in Vortex with Sink  

E-Print Network [OSTI]

Using Komar's definition, we give expressions for the mass and angular momentum of a rotating acoustic black hole. We show that the mass and angular momentum so defined, obey the equilibrium version of the first law of Black Hole thermodynamics. We also show that when a phonon passes by a vortex with a sink, its trajectory is bent. The angle of bending of the sound wave to leading order is quadratic in $A/cb$ and $B/cb$, where $b$ is the impact parameter and $A$ and $B$ are the parameters in the velocity of the fluid flow. The time delay in the propagation of sound wave which to first order depends only on $B/c^2$ and is independent of $A$.

Soumen Basak

2003-11-17T23:59:59.000Z

362

Mother templates for gravitational wave chirps  

E-Print Network [OSTI]

Templates used in a search for binary black holes and neutron stars in gravitational wave interferometer data will have to be computed on-line since the computational storage and retrieval costs for the template bank are too expensive. The conventional dimensionless variable $T=(c^3/Gm)t,$ where $m$ is the total mass of a binary, in the time-domain and a not-so-conventional velocity-like variable $v=(\\pi Gm f)^{1/3}$ in the Fourier-domain, render the phasing of the waves independent of the total mass of the system enabling the construction of {\\it mother templates} that depend only on the mass ratio of a black hole binary. Use of such mother templates in a template bank will bring about a reduction in computational costs up to a factor of 10 and a saving on storage by a factor of 100.

B. S. Sathyaprakash

2000-10-11T23:59:59.000Z

363

A Langmuir Probe Diagnostic for Use in Inhomogeneous, Time-Varying Plasmas Produced by High-Energy Laser Ablation  

SciTech Connect (OSTI)

Langmuir probes (LP) are used extensively to characterize plasma environments produced by radio frequency, pulsed plasma thrusters, and laser ablation. We discuss here the development of a LP diagnostic to examine high-density, high-temperature inhomogeneous plasmas such as those that can be created at the University of Rochester's Laboratory for Laser Energetics OMEGA facility. We have configured our diagnostic to examine the velocity of the plasma expanding from the target. We observe velocities of approximately 16-17 cm/{micro}s, with individual LP currents displaying complex structures, perhaps due to the multiple atomic species and ionization states that exist.

Patterson, J R; Emig, J A; Fournier, K B; Jenkins, P P; Trautz, K M; Seiler, S W; Davis, J F

2012-05-01T23:59:59.000Z

364

Cycloidal Wave Energy Converter  

SciTech Connect (OSTI)

This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will exceed this initial performance estimates. In advancing the Technology Readiness Level (TRL) of this type of wave energy converter from 3 to 4, we find the CycWEC to exceed our initial estimates in terms of hydrodynamic performance. Once fully developed and optimized, it has the potential to not just outperform all other WEC technologies, but to also deliver power at a lower LCOE than competing conventional renewables like wind and solar. Given the large wave power resource both domestically and internationally, this technology has the potential to lead to a large improvement in our ability to produce clean electricity at affordable cost.

Stefan G. Siegel, Ph.D.

2012-11-30T23:59:59.000Z

365

Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Final Report  

SciTech Connect (OSTI)

The objective of our research was to develop and demonstrate seismic data-acquisition and data-processing technologies that allow geothermal prospects below high-velocity rock outcrops to be evaluated. To do this, we acquired a 3-component seismic test line across an area of exposed high-velocity rocks in Brewster County, Texas, where there is high heat flow and surface conditions mimic those found at numerous geothermal prospects. Seismic contractors have not succeeded in creating good-quality seismic data in this area for companies who have acquired data for oil and gas exploitation purposes. Our test profile traversed an area where high-velocity rocks and low-velocity sediment were exposed on the surface in alternating patterns that repeated along the test line. We verified that these surface conditions cause non-ending reverberations of Love waves, Rayleigh waves, and shallow critical refractions to travel across the earth surface between the boundaries of the fast-velocity and slow-velocity material exposed on the surface. These reverberating surface waves form the high level of noise in this area that does not allow reflections from deep interfaces to be seen and utilized. Our data-acquisition method of deploying a box array of closely spaced geophones allowed us to recognize and evaluate these surface-wave noise modes regardless of the azimuth direction to the surface anomaly that backscattered the waves and caused them to return to the test-line profile. With this knowledge of the surface-wave noise, we were able to process these test-line data to create P-P and SH-SH images that were superior to those produced by a skilled seismic data-processing contractor. Compared to the P-P data acquired along the test line, the SH-SH data provided a better detection of faults and could be used to trace these faults upward to the boundaries of exposed surface rocks. We expanded our comparison of the relative value of S-wave and P-wave seismic data for geothermal applications by inserting into this report a small part of the interpretation we have done with 3C3D data across Wister geothermal field in the Imperial Valley of California. This interpretation shows that P-SV data reveal faults (and by inference, also fractures) that cannot be easily, or confidently, seen with P-P data, and that the combination of P-P and P-SV data allows VP/VS velocity ratios to be estimated across a targeted reservoir interval to show where an interval has more sandstone (the preferred reservoir facies). The conclusion reached from this investigation is that S-wave seismic technology can be invaluable to geothermal operators. Thus we developed a strong interest in understanding the direct-S modes produced by vertical-force sources, particularly vertical vibrators, because if it can be demonstrated that direct-S modes produced by vertical-force sources can be used as effectively as the direct-S modes produced by horizontal-force sources, geothermal operators can acquire direct-S data across many more prospect areas than can be done with horizontal-force sources, which presently are limited to horizontal vibrators. We include some of our preliminary work in evaluating direct-S modes produced by vertical-force sources.

Hardage, Bob A; DeAngelo, Michael V; Ermolaeva, Elena; Hardage, Bob A; Remington, Randy; Sava, Diana; Wagner, Donald; Wei, Shuijion

2013-02-28T23:59:59.000Z

366

The Systemic Velocity of Eta Carinae  

E-Print Network [OSTI]

High-resolution spectra of molecular hydrogen in the Homunculus nebula allow for the first direct measurement of the systemic velocity of Eta Carinae. Near-infrared long-slit data for H2 1-0 S(1) lambda 21218 obtained with the Phoenix spectrometer on the Gemini South telescope give Vsys=-8.1pm1 km/s (heliocentric), or VLSR=-19.7pm1 km/s, from the average of the near and far sides of the Homunculus. This measurement considerably improves the precision for the value of -7pm10 km/s inferred from neighboring O-type stars in the Carina nebula. New near-infrared spectra also provide a high-resolution line profile of [Fe II] lambda 16435 emission from gas condensations known as the Weigelt objects without contamination from the central star, revealing a line shape with complex kinematic structure. Previously, uncertainty in the Weigelt knots' kinematics was dominated by the adopted systemic velocity of Eta Car.

Nathan Smith

2004-06-23T23:59:59.000Z

367

Three-dimensional P and S waves velocity structures of the Coso...  

Open Energy Info (EERE)

structures of the Coso geothermal area, California, from microseismic travel time data Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

368

E-Print Network 3.0 - aortic pulse-wave velocity Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Fluid Dynamics ECCOMAS CDF 2006 Summary: . Priaux (Eds) TU Delft, Delft The Netherland, 2006 THE INFLUENCE OF ASYMMETRIC INFLOW IN ABDOMINAL AORTIC... the hemodynamics in...

369

Crust and Upper Mantle P Wave Velocity Structure Beneath Valles Caldera,  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin:EnergyWisconsin:2003)Crowley County, Colorado: Energy ResourcesCrucialCrump'sNew

370

P wave velocity variations in the Coso region, California, derived from  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy ResourcesLoading map...(UtilityCounty,Orleans County, Vermont:OttawaCounty,2.8247524°,is alocal

371

Three-dimensional P and S waves velocity structures of the Coso geothermal  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:Seadov Pty LtdSteen,Ltd Jump JumpAl., 1978) |Thrall, Texas: EnergyThree RiversOpenarea,

372

Application of a fiber optic probe to the hydrodynamic study of an industrial fluidized bed furnace  

SciTech Connect (OSTI)

A fiber optic probe technique is used to establish the hydrodynamic characteristics of an industrial scale (0.9 m internal diameter and 2.5 m tall) bubbling fluidized bed. This measurement technique allows for the bubbling phenomenon to be studied locally. Bubble parameters such as size, velocity and frequency can be measured with an adequate accuracy. This, however, is not a straight forward procedure, since among other things the shape of the bubble and the position at which fiber intercepts the bubble are unknown. This requires a statistical treatment of the data and the use of a correction factor. A geometrical and statistical analysis of the bubble/probe interactions shows that the correction factor is approximately unitary and thus the bubble size distribution can be obtained directly from the statistical treatment of the results of relatively large number of series of measurements. In addition, sampling rate and sample duration have to be determined as a function of the bubble size and velocity. Several combinations of sampling time and sampling rate have been tested allowing for the best combination of these parameters to be determined. After treatment of the acquired signals, the mean bubble size and velocity were calculated. The results obtained were compared to the measured expansion of the bed and the overall gas flow rate. This confirmed the accuracy of the measurements and the usefulness of this technique to establish the hydrodynamics of bubbling fluidized beds.

Saberi, B.; Shakourzadeh, K. [Technical Univ. of Compiegne (France); Militzer, J. [Technical Univ. of Nova Scotia, Halifax, Nova Scotia (Canada)

1997-12-31T23:59:59.000Z

373

On plane waves in diluted relativistic cold plasmas  

E-Print Network [OSTI]

We briefly report on some exact results [G. Fiore, arXiv:1312.4665 preprint, to appear in J. Phys. A] regarding plane waves in a relativistic cold plasma. If the plasma, initially at rest, is reached by a transverse plane electromagnetic travelling-wave, then its motion has a very simple dependence on this wave in the limit of zero density, otherwise can be determined by an iterative procedure whose accuracy decreases with time or the plasma density. Thus one can describe in particular the impact of a very intense and short laser pulse onto a plasma and determine conditions for the "slingshot effect" [G. Fiore, R. Fedele, U. De Angelis, arXiv:1309.1400 preprint] to occur. The motion in vacuum of a charged test particle subject to a wave of the same kind is also determined, for any initial velocity.

Gaetano Fiore

2014-05-01T23:59:59.000Z

374

On the fully nonlinear acoustic waves in a plasma with positrons beam impact and superthermal electrons  

SciTech Connect (OSTI)

Arbitrary amplitude ion-acoustic waves in an unmagnetized plasma consisting of cold positive ions, superthermal electrons, and positrons beam are reported. The basic set of fluid equations is reduced to an energy-balance like equation. The latter is numerically analyzed to examine the existence regions for solitary and shock waves. It is found that only solitary waves can propagate, however, the model cannot support shocks. The effects of superthermality and beam parameters (via, positrons concentration and streaming velocity) on the existence region, as well as solitary wave profile have been discussed.

Ali Shan, S. [Theoretical Plasma Physics Division, PINSTECH, Nilore, 44000 Islamabad (Pakistan) [Theoretical Plasma Physics Division, PINSTECH, Nilore, 44000 Islamabad (Pakistan); National Centre For Physics (NCP), Shahdra Valley Road, 44000 Islamabad (Pakistan); Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad (Pakistan); El-Tantawy, S. A.; Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt)] [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt)

2013-08-15T23:59:59.000Z

375

Hypersonic wave propagation in the triton X-100 2014 water gelation system as studied by Brillouin spectroscopy  

E-Print Network [OSTI]

1211 Hypersonic wave propagation in the triton X-100 2014 water gelation system as studied, quelle que soit la concentration de triton X-100. Abstract 2014 The hypersonic velocity and absorption refractometer. Analysis of the results show that in the gel phase hypersonic waves propagate effectively through

Paris-Sud XI, Université de

376

Seismic Velocity Estimation from Time Migration Maria Kourkina Cameron  

E-Print Network [OSTI]

Seismic Velocity Estimation from Time Migration by Maria Kourkina Cameron Diplom (Moscow Institute Dung-Hai Lee Spring 2007 #12;Seismic Velocity Estimation from Time Migration Copyright c 2007 by Maria Kourkina Cameron #12;Abstract Seismic Velocity Estimation from Time Migration by Maria Kourkina Cameron

Cameron, Maria Kourkina

377

LAMINAR BURNING VELOCITY OF GASOLINES WITH ADDITION OF ETHANOL  

E-Print Network [OSTI]

1 LAMINAR BURNING VELOCITY OF GASOLINES WITH ADDITION OF ETHANOL P. Dirrenberger1 , P.A. Glaude*1 (2014) 162-169" DOI : 10.1016/j.fuel.2013.07.015 #12;2 LAMINAR BURNING VELOCITY OF GASOLINES, Sweden Abstract The adiabatic laminar burning velocities of a commercial gasoline and of a model fuel (n

Boyer, Edmond

378

On Approximating the Translational Velocity of Vortex Rings  

E-Print Network [OSTI]

from this configuration and the system scaling. Here, the accuracy of this approximation is presented orifice in a flat plate contain a converging radial component of velocity. For both configurations. By this definition, the piston velocity is the average jet velocity passing through the orifice independent

Mohseni, Kamran

379

Probing Signal Design for Power System Identification  

SciTech Connect (OSTI)

This paper investigates the design of effective input signals for low-level probing of power systems. In 2005, 2006, and 2008 the Western Electricity Coordinating Council (WECC) conducted four large-scale system wide tests of the western interconnected power system where probing signals were injected by modulating the control signal at the Celilo end of the Pacific DC intertie. A major objective of these tests is the accurate estimation of the inter-area electromechanical modes. A key aspect of any such test is the design of an effective probing signal that leads to measured outputs rich in information about the modes. This paper specifically studies low-level probing signal design for power-system identification. The paper describes the design methodology and the advantages of this new probing signal which was successfully applied during these tests. This probing input is a multi-sine signal with its frequency content focused in the range of the inter-area modes. The period of the signal is over two minutes providing high-frequency resolution. Up to 15 cycles of the signal are injected resulting in a processing gain of 15. The resulting system response is studied in the time and frequency domains. Because of the new probing signal characteristics, these results show significant improvement in the output SNR compared to previous tests.

Pierre, John W.; Zhou, Ning; Tuffner, Francis K.; Hauer, John F.; Trudnowski, Daniel J.; Mittelstadt, William

2010-05-31T23:59:59.000Z

380

Nonlinear spherical Alfven waves  

E-Print Network [OSTI]

We present an one-dimensional numerical study of Alfven waves propagating along a radial magnetic field. Neglecting losses, any spherical Alfven wave, no matter how small its initial amplitude is, becomes nonlinear at sufficiently large radii. From previous simulations of Alfven waves in plane parallel atmospheres we did expect the waves to steepen and produce current sheets in the nonlinear regime, which was confirmed by our new calculations. On the other hand we did find that even the least nonlinear waves were damped out almost completely before 10 solar radii. A damping of that kind is required by models of Alfven wave-driven winds from old low-mass stars as these winds are mainly accelerated within a few stellar radii.

Ulf Torkelsson; G. Christopher Boynton

1997-09-23T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Atmospheric Solids Analysis Probe Mass Spectrometry: A New Approach...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atmospheric Solids Analysis Probe Mass Spectrometry: A New Approach for Airborne Particle Analysis. Atmospheric Solids Analysis Probe Mass Spectrometry: A New Approach for Airborne...

382

Understanding Atom Probe Tomography of Oxide-Supported Metal...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atom Probe Tomography of Oxide-Supported Metal Nanoparticles by Correlation with Atomic Resolution Electron Understanding Atom Probe Tomography of Oxide-Supported Metal...

383

THE EFFECT OF THE PRE-DETONATION STELLAR INTERNAL VELOCITY PROFILE ON THE NUCLEOSYNTHETIC YIELDS IN TYPE Ia SUPERNOVA  

SciTech Connect (OSTI)

A common model of the explosion mechanism of Type Ia supernovae is based on a delayed detonation of a white dwarf. A variety of models differ primarily in the method by which the deflagration leads to a detonation. A common feature of the models, however, is that all of them involve the propagation of the detonation through a white dwarf that is either expanding or contracting, where the stellar internal velocity profile depends on both time and space. In this work, we investigate the effects of the pre-detonation stellar internal velocity profile and the post-detonation velocity of expansion on the production of {alpha}-particle nuclei, including {sup 56}Ni, which are the primary nuclei produced by the detonation wave. We perform one-dimensional hydrodynamic simulations of the explosion phase of the white dwarf for center and off-center detonations with five different stellar velocity profiles at the onset of the detonation. In order to follow the complex flows and to calculate the nucleosynthetic yields, approximately 10,000 tracer particles were added to every simulation. We observe two distinct post-detonation expansion phases: rarefaction and bulk expansion. Almost all the burning to {sup 56}Ni occurs only in the rarefaction phase, and its expansion timescale is influenced by pre-existing flow structure in the star, in particular by the pre-detonation stellar velocity profile. We find that the mass fractions of the {alpha}-particle nuclei, including {sup 56}Ni, are tight functions of the empirical physical parameter {rho}{sub up}/v{sub down}, where {rho}{sub up} is the mass density immediately upstream of the detonation wave front and v{sub down} is the velocity of the flow immediately downstream of the detonation wave front. We also find that v{sub down} depends on the pre-detonation flow velocity. We conclude that the properties of the pre-existing flow, in particular the internal stellar velocity profile, influence the final isotopic composition of burned matter produced by the detonation.

Kim, Yeunjin; Jordan, G. C. IV; Graziani, Carlo; Lamb, D. Q.; Truran, J. W. [Astronomy Department, University of Chicago, Chicago, IL 60637 (United States); Meyer, B. S. [Physics and Astronomy Department, Clemson University, Clemson, SC 29634 (United States)

2013-07-01T23:59:59.000Z

384

Hysteresis of ionization waves  

SciTech Connect (OSTI)

A quasi-logistic, nonlinear model for ionization wave modes is introduced. Modes are due to finite size of the discharge and current feedback. The model consists of competing coupled modes and it incorporates spatial wave amplitude saturation. The hysteresis of wave mode transitions under current variation is reproduced. Sidebands are predicted by the model and found in experimental data. The ad hoc model is equivalent to a general--so-called universal--approach from bifurcation theory.

Dinklage, A. [Max-Planck-Institut fuer Plasmaphysik, EURATOM-Association, Wendelsteinstr. 1, 17491 Greifswald (Germany); Bruhn, B.; Testrich, H. [Institut fuer Physik, E.-M.-Arndt Universitaet Greifswald, Felix-Hausdorff-Str. 6, 17487 Greifswald (Germany); Wilke, C. [Leibniz-Institut fuer Plasmaforschung und Technologie, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

2008-06-15T23:59:59.000Z

385

Probing Organic Transistors with Infrared Beams  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar Home DesignPresentationsSRS Responds toPrivacy ActProbingProbingProbing

386

Structure-borne sound Flexural wave (bending wave)  

E-Print Network [OSTI]

1 Structure-borne sound · Flexural wave (bending wave) »One dimensional (beam) +(/x)dx +(/x)dx = (/x) (/x)dx=(2/x2)dx Mz +(Mz/x)dx Mz vy Fy Fy +(Fy/x)dx Structure-borne sound · Bending wave ­ flexural wave #12;2 Structure-borne sound · Two obliquely propagating waves + - + + - + - Structure

Berlin,Technische Universität

387

Wave Propagation Theory 2.1 The Wave Equation  

E-Print Network [OSTI]

2 Wave Propagation Theory 2.1 The Wave Equation The wave equation in an ideal fluid can be derived #12;66 2. Wave Propagation Theory quantities of the quiescent (time independent) medium are identified perturbations is much smaller than the speed of sound. 2.1.1 The Nonlinear Wave Equation Retaining higher

388

Wave momentum flux parameter: a descriptor for nearshore waves  

E-Print Network [OSTI]

Wave momentum flux parameter: a descriptor for nearshore waves Steven A. Hughes* US Army Engineer Available online 7 October 2004 Abstract A new parameter representing the maximum depth-integrated wave momentum flux occurring over a wave length is proposed for characterizing the wave contribution

US Army Corps of Engineers

389

Shallow Water Waves and Solitary Waves Willy Hereman  

E-Print Network [OSTI]

Shallow Water Waves and Solitary Waves Willy Hereman Department of Mathematical and Computer of the Subject II. Introduction­Historical Perspective III. Completely Integrable Shallow Water Wave Equations IV. Shallow Water Wave Equations of Geophysical Fluid Dynamics V. Computation of Solitary Wave Solutions VI

Hereman, Willy A.M.

390

Force-velocity relations for multiple molecular motor transportation  

E-Print Network [OSTI]

A transition rate model of cargo transportation by N effective molecular motors is proposed. Under the assumption of steady state, the force-velocity curve of multi-motor system can be derived from the force-velocity curve of single motor. Our work shows, in the case of low load, the velocity of multi-motor system can decrease or increase with increasing motor number, which is dependent on the single motor force-velocity curve. And most commonly, the velocity decreases. This gives a possible explanation to some recent experimental observations.

Wang, Ziqing

2009-01-01T23:59:59.000Z

391

Force-velocity relations for multiple-molecular-motor transport  

E-Print Network [OSTI]

A transition rate model of cargo transport by $N$ molecular motors is proposed. Under the assumption of steady state, the force-velocity curve of multi-motor system can be derived from the force-velocity curve of single motor. Our work shows, in the case of low load, the velocity of multi-motor system can decrease or increase with increasing motor number, which is dependent on the single motor force-velocity curve. And most commonly, the velocity decreases. This gives a possible explanation to some recent

Ziqing Wang; Ming Li

2009-10-01T23:59:59.000Z

392

Filament velocity scaling laws for warm ions  

SciTech Connect (OSTI)

The dynamics of filaments or blobs in the scrape-off layer of magnetic fusion devices are studied by magnitude estimates of a comprehensive drift-interchange-Alfvén fluid model. The standard blob models are reproduced in the cold ion case. Even though usually neglected, in the scrape-off layer, the ion temperature can exceed the electron temperature by an order of magnitude. The ion pressure affects the dynamics of filaments amongst others by adding up to the interchange drive and the polarisation current. It is shown how both effects modify the scaling laws for filament velocity in dependence of its size. Simplifications for experimentally relevant limit regimes are given. These are the sheath dissipation, collisional, and electromagnetic regime.

Manz, P. [Physik-Department E28, Technische Universität München, James-Franck-Str. 1, 85748 Garching (Germany) [Physik-Department E28, Technische Universität München, James-Franck-Str. 1, 85748 Garching (Germany); Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, Boltzmannstr. 2, 85748 Garching (Germany); Carralero, D.; Birkenmeier, G.; Müller, H. W.; Scott, B. D. [Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, Boltzmannstr. 2, 85748 Garching (Germany)] [Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, Boltzmannstr. 2, 85748 Garching (Germany); Müller, S. H. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego 92093 (United States)] [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego 92093 (United States); Fuchert, G. [Insitut für Grenzflächenverfahrenstechnik und Plasmatechnologie, Universität Stuttgart, 70569 Stuttgart (Germany)] [Insitut für Grenzflächenverfahrenstechnik und Plasmatechnologie, Universität Stuttgart, 70569 Stuttgart (Germany); Stroth, U. [Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, Boltzmannstr. 2, 85748 Garching (Germany) [Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, Boltzmannstr. 2, 85748 Garching (Germany); Physik-Department E28, Technische Universität München, James-Franck-Str. 1, 85748 Garching (Germany)

2013-10-15T23:59:59.000Z

393

Peculiarity of convergence of shock wave generated by underwater electrical explosion of ring-shaped wire  

SciTech Connect (OSTI)

Nanosecond timescale underwater electrical wire explosions of ring-shaped Cu wires were investigated using a pulsed generator with a current amplitude up to 50 kA. It was shown that this type of wire explosion results in the generation of a toroidal shock wave (SW). Time- and space-resolved optical diagnostics were used to determine azimuthal uniformity of the shock wave front and its velocity. It was found that the shock wave preserves its circular front shape in the range of radii 50?mwave propagates with a constant velocity of v{sub sw}=1.2M, where M is the Mach number. The dynamics of the leading part of the shock wave, based on the oblique shock wave theory, is presented, explaining the constant velocity of the shock wave.

Shafer, D.; Toker, G. R.; Gurovich, V. Tz.; Gleizer, S.; Krasik, Ya. E. [Physics Department, Technion, Haifa 32000 (Israel)] [Physics Department, Technion, Haifa 32000 (Israel)

2013-05-15T23:59:59.000Z

394

PLASMA DIAGNOSTICS OF AN EIT WAVE OBSERVED BY HINODE/EIS AND SDO/AIA  

SciTech Connect (OSTI)

We present plasma diagnostics of an Extreme-Ultraviolet Imaging Telescope (EIT) wave observed with high cadence in Hinode/Extreme-Ultraviolet Imaging Spectrometer (EIS) sit-and-stare spectroscopy and Solar Dynamics Observatory/Atmospheric Imaging Assembly imagery obtained during the HOP-180 observing campaign on 2011 February 16. At the propagating EIT wave front, we observe downward plasma flows in the EIS Fe XII, Fe XIII, and Fe XVI spectral lines (log T Almost-Equal-To 6.1-6.4) with line-of-sight (LOS) velocities up to 20 km s{sup -1}. These redshifts are followed by blueshifts with upward velocities up to -5 km s{sup -1} indicating relaxation of the plasma behind the wave front. During the wave evolution, the downward velocity pulse steepens from a few km s{sup -1} up to 20 km s{sup -1} and subsequently decays, correlated with the relative changes of the line intensities. The expected increase of the plasma densities at the EIT wave front estimated from the observed intensity increase lies within the noise level of our density diagnostics from EIS Fe XIII 202/203 A line ratios. No significant LOS plasma motions are observed in the He II line, suggesting that the wave pulse was not strong enough to perturb the underlying chromosphere. This is consistent with the finding that no H{alpha} Moreton wave was associated with the event. The EIT wave propagating along the EIS slit reveals a strong deceleration of a Almost-Equal-To -540 m s{sup -2} and a start velocity of v{sub 0} Almost-Equal-To 590 km s{sup -1}. These findings are consistent with the passage of a coronal fast-mode MHD wave, pushing the plasma downward and compressing it at the coronal base.

Veronig, A. M.; Kienreich, I. W.; Muhr, N.; Temmer, M. [Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria); Goemoery, P. [Astronomical Institute, Slovak Academy of Sciences, SK-05960 Tatranska Lomnica (Slovakia); Vrsnak, B. [Hvar Observatory, Faculty of Geodesy, Kaciceva 26, 1000 Zagreb (Croatia); Warren, H. P., E-mail: astrid.veronig@uni-graz.at [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2011-12-10T23:59:59.000Z

395

Wave induced forces on a partially exposed circular cylinder  

E-Print Network [OSTI]

analyzed to give a dimensionless force which was related to the wave parameters H/L and d/L. Other methods of analysis were also used for the derivation of drag, inertia, and lift coefficients for use with various forms of the Norison Equation. RCKHOI... = Fluid Density A = Area of Hodel u = Horizontal Hater Particle Velocity x In a study conducted by Chakrabarti (9), the data presented by Shank and Herbich were analyzed by a different method, namely a closed form expression for the wave forces. Only...

Parker, Michael Edward

1977-01-01T23:59:59.000Z

396

Hohlraum Designs for High Velocity Implosions on NIF  

SciTech Connect (OSTI)

In this paper, we compare experimental shock and capsule trajectories to design calculations using the radiation-hydrodynamics code HYDRA. The measured trajectories from surrogate ignition targets are consistent with reducing the x-ray flux on the capsule by about 85%. A new method of extracting the radiation temperature as seen by the capsule from x-ray intensity and image data shows that about half of the apparent 15% flux deficit in the data with respect to the simulations can be explained by HYDRA overestimating the x-ray flux on the capsule. The National Ignition Campaign (NIC) point-design target is designed to reach a peak fuel-layer velocity of 370 km/s by ablating 90% of its plastic (CH) ablator. The 192-beam National Ignition Facility laser drives a gold hohlraum to a radiation temperature (T{sub RAD}) of 300 eV with a 20 ns-long, 420 TW, 1.3 MJ laser pulse. The hohlraum x-rays couple to the CH ablator in order to apply the required pressure to the outside of the capsule. In this paper, we compare experimental measurements of the hohlraum T{sub RAD} and the implosion trajectory with design calculations using the code hydra. The measured radial positions of the leading shock wave and the unablated shell are consistent with simulations in which the x-ray flux on the capsule is artificially reduced by 85%. We describe a new method of inferring the T{sub RAD} seen by the capsule from time-dependent x-ray intensity data and static x-ray images. This analysis shows that hydra overestimates the x-ray flux incident on the capsule by {approx}8%.

Meezan, N B; Hicks, D G; Callahan, D A; Olson, R E; Schneider, M S; Thomas, C A; Robey, H F; Celliers, P M; Kline, J K; Dixit, S N; Michel, P A; Jones, O S; Clark, D S; Ralph, J E; Doeppner, T; MacKinnon, A J; Haan, S W; Landen, O L; Glenzer, S H; Suter, L J; Edwards, M J; Macgowan, B J; Lindl, J D; Atherton, L J

2011-10-19T23:59:59.000Z

397

Theory of steady-state plane tunneling-assisted impact ionization waves  

SciTech Connect (OSTI)

The effect of band-to-band and trap-assisted tunneling on the properties of steady-state plane ionization waves in p{sup +}-n-n{sup +} structures is theoretically analyzed. It is shown that such tunneling-assisted impact ionization waves do not differ in a qualitative sense from ordinary impact ionization waves propagating due to the avalanche multiplication of uniformly distributed seed electrons and holes. The quantitative differences of tunneling-assisted impact ionization waves from impact ionization waves are reduced to a slightly different relation between the wave velocity u and the maximum field strength E{sub M} at the front. It is shown that disregarding impact ionization does not exclude the possibility of the existence of tunneling-assisted ionization waves; however, their structure radically changes, and their velocity strongly decreases for the same E{sub M}. A comparison of the dependences u(E{sub M}) for various ionization-wave types makes it possible to determine the conditions under which one of them is dominant. In conclusion, unresolved problems concerning the theory of tunneling-assisted impact ionization waves are discussed and the directions of further studies are outlined.

Kyuregyan, A. S., E-mail: ask@vei.ru [Lenin All-Russian Electrical-Engineering Institute (Russian Federation)

2013-07-15T23:59:59.000Z

398

Catheter based magnetic resonance compatible perfusion probe  

E-Print Network [OSTI]

Neurosurgeons are using a thermal based technique to quantify brain perfusion. The thermal diffusion probe (TDP) technology measures perfusion in a relatively small volume of brain tissue. The neurosurgeon chooses the ...

Toretta, Cara Lynne

2007-01-01T23:59:59.000Z

399

Modulated microwave microscopy and probes used therewith  

DOE Patents [OSTI]

A microwave microscope including a probe tip electrode vertically positionable over a sample and projecting downwardly from the end of a cantilever. A transmission line connecting the tip electrode to the electronic control system extends along the cantilever and is separated from a ground plane at the bottom of the cantilever by a dielectric layer. The probe tip may be vertically tapped near or at the sample surface at a low frequency and the microwave signal reflected from the tip/sample interaction is demodulated at the low frequency. Alternatively, a low-frequency electrical signal is also a non-linear electrical element associated with the probe tip to non-linearly interact with the applied microwave signal and the reflected non-linear microwave signal is detected at the low frequency. The non-linear element may be semiconductor junction formed near the apex of the probe tip or be an FET formed at the base of a semiconducting tip.

Lai, Keji; Kelly, Michael; Shen, Zhi-Xun

2012-09-11T23:59:59.000Z

400

Lecture Notes on Langmuir Probe Diagnostics  

E-Print Network [OSTI]

University of California, Los Angeles Mini-Course on Plasma Diagnostics, IEEE-ICOPS meeting, Jeju, KoreaLecture Notes on Langmuir Probe Diagnostics Francis F. Chen Electrical Engineering Department...................................................................25 1. Fully ionized plasmas

Chen, Francis F.

Note: This page contains sample records for the topic "velocity wave probe" 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

Surface sampling concentration and reaction probe  

DOE Patents [OSTI]

A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

Van Berkel, Gary J; Elnaggar, Mariam S

2013-07-16T23:59:59.000Z

402

Probes of strong-field gravity  

E-Print Network [OSTI]

In this thesis, I investigate several ways to probe gravity in the strong-field regime. These investigations focus on observables from the gravitational dynamics, i.e. when time derivatives are large: thus I focus on sources ...

Stein, Leo Chaim

2012-01-01T23:59:59.000Z

403

Single Molecule Probes of Lipid Membrane Structure  

E-Print Network [OSTI]

Biological membranes are highly heterogeneous structures that are thought to use this heterogeneity to organize and modify the function of membrane constituents. Probing membrane organization, structure, and changes therein ...

Livanec, Philip W.

2009-12-14T23:59:59.000Z

404

Self-referencing remote optical probe  

DOE Patents [OSTI]

A probe for remote spectrometric measurements of fluid samples having a hollow probe body with a sliding reflective plug therein and a lens at one end, ports for admitting and expelling the fluid sample and a means for moving the reflector so that reference measurement can be made with the reflector in a first position near the lens and a sample measurement can be made with the reflector away from the lens and the fluid sample between the reflector and the lens. Comparison of the two measurements will yield the composition of the fluid sample. The probe is preferably used for remote measurements and light is carried to and from the probe via fiber optic cables.

O'Rourke, Patrick E. (157 Greenwood Dr., Martinez, GA 30907); Prather, William S. (2419 Dickey Rd., Augusta, GA 30906); Livingston, Ronald R. (137 Breckenridge Dr., N. Augusta, GA)

1991-01-01T23:59:59.000Z

405

Self-referencing remote optical probe  

DOE Patents [OSTI]

A probe is described for remote spectrometric measurements of fluid samples having a hollow probe body with a sliding reflective plug therein and a lens at one end, ports for admitting and expelling the fluid sample and a means for moving the reflector so that reference measurement can be made with the reflector in a first position near the lens and a sample measurement can be made with the reflector away from the lens and the fluid sample between the reflector and the lens. Comparison of the two measurements will yield the composition of the fluid sample. The probe is preferably used for remote measurements and light is carried to and from the probe via fiber optic cables. 3 figures.

O'Rourke, P.E.; Prather, W.S.; Livingston, R.R.

1991-08-13T23:59:59.000Z

406

Wave runup on cylinders subject to deep water random waves  

E-Print Network [OSTI]

was measured close to the test cylinders are analyzed. These data on wave runup in deepwater random waves were generated at similar water depths with significant wave heights and spectral peak periods. Statistical parameters, zero crossing analysis...

Indrebo, Ann Kristin

2012-06-07T23:59:59.000Z

407

AdHoc Probe: End-to-end Capacity Probing in Wireless Ad Hoc Networks  

E-Print Network [OSTI]

AdHoc Probe: End-to-end Capacity Probing in Wireless Ad Hoc Networks Ling-Jyh Chen1 , Tony Sun2 and systematic study in ad hoc, multihop wireless networks is still lacking. Yet the rate of a wireless link can deployment. In this paper, we present AdHoc Probe, a packet-pair based technique, to estimate end-to-end path

Chen, Ling-Jyh

408

Wave-Corpuscle Mechanics for Electric Charges  

E-Print Network [OSTI]

superposition in nonlinear wave dynamics. Rev. Math. Phys.6. Babin, A. , Figotin, A. : Wave-corpuscle mechanics forV. , Fortunato, D. : Solitary waves in the nonlinear wave

Babin, Anatoli; Figotin, Alexander

2010-01-01T23:59:59.000Z

409

System and method to estimate compressional to shear velocity (VP/VS) ratio in a region remote from a borehole  

DOE Patents [OSTI]

In some aspects of the disclosure, a method for creating three-dimensional images of non-linear properties and the compressional to shear velocity ratio in a region remote from a borehole using a conveyed logging tool is disclosed. In some aspects, the method includes arranging a first source in the borehole and generating a steered beam of elastic energy at a first frequency; arranging a second source in the borehole and generating a steerable beam of elastic energy at a second frequency, such that the steerable beam at the first frequency and the steerable beam at the second frequency intercept at a location away from the borehole; receiving at the borehole by a sensor a third elastic wave, created by a three wave mixing process, with a frequency equal to a difference between the first and second frequencies and a direction of propagation towards the borehole; determining a location of a three wave mixing region based on the arrangement of the first and second sources and on properties of the third wave signal; and creating three-dimensional images of the non-linear properties using data recorded by repeating the generating, receiving and determining at a plurality of azimuths, inclinations and longitudinal locations within the borehole. The method is additionally used to generate three dimensional images of the ratio of compressional to shear acoustic velocity of the same volume surrounding the borehole.

Vu, Cung; Nihei, Kurt T; Schmitt, Denis P; Skelt, Christopher; Johnson, Paul A; Guyer, Robert; TenCate, James A; Le Bas, Pierre-Yves

2012-10-16T23:59:59.000Z

410

Fiber optic probe for light scattering measurements  

DOE Patents [OSTI]

A fiber optic probe and a method for using the probe for light scattering analyses of a sample. The probe includes a probe body with an inlet for admitting a sample into an interior sample chamber, a first optical fiber for transmitting light from a source into the chamber, and a second optical fiber for transmitting light to a detector such as a spectrophotometer. The interior surface of the probe carries a coating that substantially prevents non-scattered light from reaching the second fiber. The probe is placed in a region where the presence and concentration of an analyte of interest are to be detected, and a sample is admitted into the chamber. Exciting light is transmitted into the sample chamber by the first fiber, where the light interacts with the sample to produce Raman-scattered light. At least some of the Raman-scattered light is received by the second fiber and transmitted to the detector for analysis. Two Raman spectra are measured, at different pressures. The first spectrum is subtracted from the second to remove background effects, and the resulting sample Raman spectrum is compared to a set of stored library spectra to determine the presence and concentration of the analyte.

Nave, Stanley E. (Evans, GA); Livingston, Ronald R. (Aiken, SC); Prather, William S. (Augusta, GA)

1995-01-01T23:59:59.000Z

411

Fiber optic probe for light scattering measurements  

DOE Patents [OSTI]

This invention is comprised of a fiber optic probe and a method for using the probe for light scattering analyses of a sample. The probe includes a probe body with an inlet for admitting a sample into an interior sample chamber, a first optical fiber for transmitting light from a source into the chamber, and a second optical fiber for transmitting light to a detector such as a spectrophotometer. The interior surface of the probe carries a coating that substantially prevents non-scattered light from reaching the second fiber. The probe is placed in a region where the presence and concentration of an analyte of interest are to be detected, and a sample is admitted into the chamber. Exciting light is transmitted into the sample chamber by the first fiber, where the light interacts with the sample to produce Raman-scattered light. At least some of the Raman- scattered light is received by the second fiber and transmitted to the detector for analysis. Two Raman spectra are measured, at different pressures. The first spectrum is subtracted from the second to remove background effects, and the resulting sample Raman spectrum is compared to a set of stored library spectra to determine the presence and concentration of the analyte.

Nave, S.E.; Livingston, R.R.; Prather, W.S.

1993-01-01T23:59:59.000Z

412

Velocity and temperature distribution of air in the boundary layer of a vertical plate for free-convective heat transfer  

E-Print Network [OSTI]

against the nozzle and clamped to. a stand in such a way that its vertical position could be, set. as desired. Hot-Wire Anemometer A Plow Corporation Model HWB2 hot wire anemometer was used in connection with a single, filament, probe to measure...VELOCITY AND TEMPERATURE DISTRIBUTION OF AIR IN THE BOUNDARY LAYER OF A VERTICAL PLATE FOR FREE-CONVECTIVE HEAT TRANSFER A Thesis By JEAN MAXIME JOSE JULLIENNE Submitted to . the . Graduate School of the Agricultural. and Mechanical. College...

Jullienne, Jean Maxime Jose

2012-06-07T23:59:59.000Z

413

Self-consistent full wave simulations of lower hybrid waves  

E-Print Network [OSTI]

Self-consistent full wave simulations of lower hybrid waves John C. Wright P. T. Bonoli - MIT E .J for Simulation of Wave-Plasma Interactions L.A. Berry, D.B. Batchelor, E.F. Jaeger, E. D`Azevedo D. Green C. Milanesio #12;3 Outline · Introduction to Lower Hybrid waves · Modeling LH waves ­ Ray tracing ­ Full Wave

Wright, John C.

414

Harmonic generation of gravitational wave induced Alfven waves  

E-Print Network [OSTI]

Here we consider the nonlinear evolution of Alfven waves that have been excited by gravitational waves from merging binary pulsars. We derive a wave equation for strongly nonlinear and dispersive Alfven waves. Due to the weak dispersion of the Alfven waves, significant wave steepening can occur, which in turn implies strong harmonic generation. We find that the harmonic generation is saturated due to dispersive effects, and use this to estimate the resulting spectrum. Finally we discuss the possibility of observing the above process.

Mats Forsberg; Gert Brodin

2007-11-26T23:59:59.000Z

415

Focused acoustic beam imaging of grain structure and local Young's modulus with Rayleigh and surface skimming longitudinal waves  

SciTech Connect (OSTI)

The interaction of a focused acoustic beam with materials generates Rayleigh surface waves (RSW) and surface skimming longitudinal waves (SSLW). Acoustic microscopic investigations have used the RSW amplitude and the velocity measurements, extensively for grain structure analysis. Although, the presence of SSLW has been recognized, it is rarely used in acoustic imaging. This paper presents an approach to perform microstructure imaging and local elastic modulus measurements by combining both RSW and SSLW. The acoustic imaging of grain structure was performed by measuring the amplitude of RSW and SSLW signal. The microstructure images obtained on the same region of the samples with RSW and SSLW are compared and the difference in the contrast observed is discussed based on the propagation characteristics of the individual surface waves. The velocity measurements are determined by two point defocus method. The surface wave velocities of RSW and SSLW of the same regions of the sample are combined and presented as average Young's modulus image.

Martin, R. W.; Sathish, S. [University of Dayton Research Institute, Structural Integrity Division 300 College Park Drive, Dayton, OH, 45469 (United States); Blodgett, M. P. [Air Force Research Lab, RXCA, Wright Patterson AFB, OH, 45433 (United States)

2013-01-25T23:59:59.000Z

416

Integrated campaign to study the stationary inertial Alfvn wave in the laboratory and space This article has been downloaded from IOPscience. Please scroll down to see the full text article.  

E-Print Network [OSTI]

are in colour only in the electronic version) 1. Introduction The stationary inertial Alfv´en (StIA) wave [1 of StIA waves is magnetic-field-aligned (s-direction in figure 1) electron drift energy that overcomes of the effective phase velocity vector, as shown, and is approximately zero. The StIA wave vector is approximately

California at Berkeley, University of

417

IJOPE Paper No JC-343AB-final 9/26/04 Biausser Page number 1 Numerical Analysis of the Internal Kinematics and Dynamics of 3D Breaking Waves on Slopes  

E-Print Network [OSTI]

Kinematics and Dynamics of 3D Breaking Waves on Slopes Benjamin Biausser1 , Stéphan T. Grilli2 , Philippe and internal kinematics (velocity, vorticity, pressure) are presented. KEY WORDS: breaking ocean waves years, our understanding of wave breaking dynamics and kinematics is still quite incomplete. Due

Grilli, Stéphan T.

418

An alpha particle diagnostic based on measurements of lower hybrid wave fluctuations  

SciTech Connect (OSTI)

It is shown that the one-dimensional alpha particle velocity distribution function can be determined from the fluctuation- dissipation theorem based on measurements of lower hybrid wave fluctuations in an equilibrium plasma. This method uses collective Thomson scattering data with large signal-to-noise ratio, but it is applicable only when the alpha particles have an isotropic velocity distribution. 16 refs., 1 fig.

Wong, K.L.

1989-07-01T23:59:59.000Z

419

Secondary dust density waves excited by nonlinear dust acoustic waves  

SciTech Connect (OSTI)

Secondary dust density waves were observed in conjunction with high amplitude (n{sub d}/n{sub d0}>2) dust acoustic waves (DAW) that were spontaneously excited in a dc glow discharge dusty plasma in the moderately coupled, {Gamma}{approx}1, state. The high amplitude dust acoustic waves produced large dust particle oscillations, displacements, and trapping. Secondary dust density waves were excited in the wave troughs of the high amplitude DAWs. The waveforms, amplitudes, wavelengths, and wave speeds of the primary DAWs and the secondary waves were measured. A dust-dust streaming instability is discussed as a possible mechanism for the production of the secondary waves.

Heinrich, J. R.; Kim, S.-H.; Meyer, J. K.; Merlino, R. L. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States); Rosenberg, M. [Department of Electrical and Computer Engineering, University of California, San Diego, California 92093 (United States)

2012-08-15T23:59:59.000Z

420

Search for long-lived gravitational-wave transients coincident with long gamma-ray bursts  

E-Print Network [OSTI]

Long gamma-ray bursts (GRBs) have been linked to extreme core-collapse supernovae from massive stars. Gravitational waves (GW) offer a probe of the physics behind long GRBs. We investigate models of long-lived (?10–1000??s) ...

Aggarwal, Nancy

Note: This page contains sample records for the topic "velocity wave probe" 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

Center for Wave Phenomena Wave Phenomena  

E-Print Network [OSTI]

into a life of scientific discovery." Kurang Mehta, Ph.D. Class of 2007 Shell Exploration and Production Phil research and education program in seismic exploration, monitoring and wave propagation. The main focus and efficiency of seismic processing algorithms, especially for application to regions of structural complexity

422

Rainbow trapping of guided waves  

E-Print Network [OSTI]

Rainbow trapping of guided waves Javier Polanco and Rosa M.the propagation of a wave packet that is a superpositionof three s-polarized guided waves with different frequencies

Polanco, Javier; Fitzgerald, Rosa M; Leskova, Tamara A; Maradudin, Alexei A

2011-01-01T23:59:59.000Z

423

Arnold Schwarzenegger CALIFORNIA OCEAN WAVE  

E-Print Network [OSTI]

Arnold Schwarzenegger Governor CALIFORNIA OCEAN WAVE ENERGY ASSESSMENT Prepared For: California this report as follows: Previsic, Mirko. 2006. California Ocean Wave Energy Assessment. California Energy Systems Integration · Transportation California Ocean Wave Energy Assessment is the final report

424

Evaluation of probes used to detect alpha radiation  

E-Print Network [OSTI]

such probes were evaluated in this study, the 350A Alpha Probe of Dosimeter Corporation and the AB100 Scintillator Probe produced by Harshaw Bicron. As an additional comparison, a Ludlum Model 44-9 (Pancake) GM Probe was also evaluated, since it has served...

Sackett, Gregory Duane

1995-01-01T23:59:59.000Z

425

Mach flow angularity probes for scramjet engine flow path diagnostics  

SciTech Connect (OSTI)

Mach-flow angularity (MFA) probes were developed for use in scramjet flow path probe rakes. Prototype probes were fabricated to demonstrate the assembly processes (numerical control machining, furnace brazing, and electron beam welding). Tests of prototype probes confirmed the thermal durability margins and life cycle. Selected probes were calibrated in air at Mach numbers from 1.75 to 6.0. Acceptance criteria for the production probes stressed thermal durability and pressure (and, consequently, Mach number) measurement quality. This new water-cooled MFA probe has 0.397-cm shaft diameter and is capable of withstanding heat fluxes of 2.724 kW/sq cm.

Jalbert, P.A.; Hiers, R.S. Jr. [Sverdrup Technology, Inc., Arnold AFS, TN (United States)

1993-12-31T23:59:59.000Z

426

A Monte Carlo simulation for kinetic chemotaxis models: an application to the traveling population wave  

E-Print Network [OSTI]

A Monte Carlo simulation for the chemotactic bacteria is developed on the basis of the kinetic modeling, i.e., the Boltzmann transport equation, and applied to the one-dimensional traveling population wave in a micro channel.In this method, the Monte Carlo method, which calculates the run-and-tumble motions of bacteria, is coupled with a finite volume method to solve the macroscopic transport of the chemical cues in the field. The simulation method can successfully reproduce the traveling population wave of bacteria which was observed experimentally. The microscopic dynamics of bacteria, e.g., the velocity autocorrelation function and velocity distribution function of bacteria, are also investigated. It is found that the bacteria which form the traveling population wave create quasi-periodic motions as well as a migratory movement along with the traveling population wave. Simulations are also performed with changing the sensitivity and modulation parameters in the response function of bacteria. It is found th...

Yasuda, Shugo

2015-01-01T23:59:59.000Z

427

QUASI-PERIODIC FAST-MODE WAVE TRAINS WITHIN A GLOBAL EUV WAVE AND SEQUENTIAL TRANSVERSE OSCILLATIONS DETECTED BY SDO/AIA  

SciTech Connect (OSTI)

We present the first unambiguous detection of quasi-periodic wave trains within the broad pulse of a global EUV wave (so-called EIT wave) occurring on the limb. These wave trains, running ahead of the lateral coronal mass ejection (CME) front of 2-4 times slower, coherently travel to distances {approx}> R{sub Sun }/2 along the solar surface, with initial velocities up to 1400 km s{sup -1} decelerating to {approx}650 km s{sup -1}. The rapid expansion of the CME initiated at an elevated height of 110 Mm produces a strong downward and lateral compression, which may play an important role in driving the primary EUV wave and shaping its front forwardly inclined toward the solar surface. The wave trains have a dominant 2 minute periodicity that matches the X-ray flare pulsations, suggesting a causal connection. The arrival of the leading EUV wave front at increasing distances produces an uninterrupted chain sequence of deflections and/or transverse (likely fast kink mode) oscillations of local structures, including a flux-rope coronal cavity and its embedded filament with delayed onsets consistent with the wave travel time at an elevated (by {approx}50%) velocity within it. This suggests that the EUV wave penetrates through a topological separatrix surface into the cavity, unexpected from CME-caused magnetic reconfiguration. These observations, when taken together, provide compelling evidence of the fast-mode MHD wave nature of the primary (outer) fast component of a global EUV wave, running ahead of the secondary (inner) slow component of CME-caused restructuring.

Liu Wei; Nitta, Nariaki V.; Aschwanden, Markus J.; Schrijver, Carolus J.; Title, Alan M.; Tarbell, Theodore D. [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Ofman, Leon, E-mail: weiliu@lmsal.com [Department of Physics, Catholic University of America, Washingtom, DC 20064 (United States)

2012-07-01T23:59:59.000Z

428

An insitu borescopic quantitative imaging profiler for the measurement of high concentration sediment velocity  

E-Print Network [OSTI]

of high concentration sediment velocity Edwin A. Cowen •instantaneous velocity in high sediment concentration ?ows,point reveals the sheet ?ow sediment velocities to be highly

Cowen, Edwin A.; Dudley, Russell D.; Liao, Qian; Variano, Evan A.; Liu, Philip L.-F.

2010-01-01T23:59:59.000Z

429

Diagonalization of pp-waves  

E-Print Network [OSTI]

A coordinate transformation is found which diagonalizes the axisymmetric pp-waves. Its effect upon concrete solutions, including impulsive and shock waves, is discussed.

B. V. Ivanov

1997-05-21T23:59:59.000Z

430

Propagation of sound waves through a spatially homogeneous but smoothly time-dependent medium  

SciTech Connect (OSTI)

The propagation of sound through a spatially homogeneous but non-stationary medium is investigated within the framework of fluid dynamics. For a non-vortical fluid, especially, a generalized wave equation is derived for the (scalar) potential of the fluid velocity distribution in dependence of the equilibrium mass density of the fluid and the sound wave velocity. A solution of this equation for a finite transition period ? is determined in terms of the hypergeometric function for a phenomenologically realistic, sigmoidal change of the mass density and sound wave velocity. Using this solution, it is shown that the energy flux of the sound wave is not conserved but increases always for the propagation through a non-stationary medium, independent of whether the equilibrium mass density is increased or decreased. It is found, moreover, that this amplification of the transmitted wave arises from an energy exchange with the medium and that its flux is equal to the (total) flux of the incident and the reflected wave. An interpretation of the reflected wave as a propagation of sound backward in time is given in close analogy to Feynman and Stueckelberg for the propagation of anti-particles. The reflection and transmission coefficients of sound propagating through a non-stationary medium is analyzed in more detail for hypersonic waves with transition periods ? between 15 and 200 ps as well as the transformation of infrasound waves in non-stationary oceans. -- Highlights: •Analytically exact study of sound propagation through a non-stationary medium. •Energy exchange between the non-stationary medium and the sound wave. •Transformation of hypersonic and ultrasound frequencies in non-stationary media. •Propagation of sound backward in time in close analogy to anti-particles. •Prediction of tsunamis both in spatially and temporally inhomogeneous oceans.

Hayrapetyan, A.G., E-mail: armen@physi.uni-heidelberg.de [Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg (Germany); Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Grigoryan, K.K.; Petrosyan, R.G. [Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan (Armenia)] [Yerevan State University, 1 Alex Manoogian Str., 0025 Yerevan (Armenia); Fritzsche, S. [Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena (Germany) [Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena (Germany); Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

2013-06-15T23:59:59.000Z

431

Out-of-plane ultrasonic velocity measurement  

DOE Patents [OSTI]

A method for improving the accuracy of measuring the velocity and time of flight of ultrasonic signals through moving web-like materials such as paper, paperboard and the like, includes a pair of ultrasonic transducers disposed on opposing sides of a moving web-like material. In order to provide acoustical coupling between the transducers and the web-like material, the transducers are disposed in fluid-filled wheels. Errors due to variances in the wheel thicknesses about their circumference which can affect time of flight measurements and ultimately the mechanical property being tested are compensated by averaging the ultrasonic signals for a predetermined number of revolutions. The invention further includes a method for compensating for errors resulting from the digitization of the ultrasonic signals. More particularly, the invention includes a method for eliminating errors known as trigger jitter inherent with digitizing oscilloscopes used to digitize the signals for manipulation by a digital computer. In particular, rather than cross-correlate ultrasonic signals taken during different sample periods as is known in the art in order to determine the time of flight of the ultrasonic signal through the moving web, a pulse echo box is provided to enable cross-correlation of predetermined transmitted ultrasonic signals with predetermined reflected ultrasonic or echo signals during the sample period. By cross-correlating ultrasonic signals in the same sample period, the error associated with trigger jitter is eliminated. 20 figs.

Hall, M.S.; Brodeur, P.H.; Jackson, T.G.

1998-07-14T23:59:59.000Z

432

Out-of-plane ultrasonic velocity measurement  

DOE Patents [OSTI]

A method for improving the accuracy of measuring the velocity and time of flight of ultrasonic signals through moving web-like materials such as paper, paperboard and the like, includes a pair of ultrasonic transducers disposed on opposing sides of a moving web-like material. In order to provide acoustical coupling between the transducers and the web-like material, the transducers are disposed in fluid-filled wheels. Errors due to variances in the wheel thicknesses about their circumference which can affect time of flight measurements and ultimately the mechanical property being tested are compensated by averaging the ultrasonic signals for a predetermined number of revolutions. The invention further includes a method for compensating for errors resulting from the digitization of the ultrasonic signals. More particularly, the invention includes a method for eliminating errors known as trigger jitter inherent with digitizing oscilloscopes used to digitize the signals for manipulation by a digital computer. In particular, rather than cross-correlate ultrasonic signals taken during different sample periods as is known in the art in order to determine the time of flight of the ultrasonic signal through the moving web, a pulse echo box is provided to enable cross-correlation of predetermined transmitted ultrasonic signals with predetermined reflected ultrasonic or echo signals during the sample period. By cross-correlating ultrasonic signals in the same sample period, the error associated with trigger jitter is eliminated.

Hall, Maclin S. (Marietta, GA); Brodeur, Pierre H. (Smyrna, GA); Jackson, Theodore G. (Atlanta, GA)

1998-01-01T23:59:59.000Z

433

True Masses of Radial-Velocity Exoplanets  

E-Print Network [OSTI]

We explore the science power of space telescopes used to estimate the true masses of known radial-velocity exoplanets by means of astrometry on direct images. We translate a desired mass accuracy (+/10% in our example) into a minimum goal for the signal-to-noise ratio, which implies a minimum exposure time. When the planet is near a node, the mass measurement becomes difficult if not impossible, because the apparent separation becomes decoupled from the inclination angle of the orbit. The combination of this nodal effect with considerations of solar and anti-solar pointing restrictions, photometric and obscurational completeness, and image blurring due to orbital motion, severely limits the observing opportunities, often to only brief intervals in a five-year mission. We compare the science power of four missions, two with external star shades, EXO-S and WFIRST-S, and two with internal coronagraphs, EXO-C and WFIRST-C. The star shades out-perform the coronagraph in this science program by about a factor of th...

Brown, Robert A

2015-01-01T23:59:59.000Z

434

Wave-wave interactions in solar type III radio bursts  

SciTech Connect (OSTI)

The high time resolution observations from the STEREO/WAVES experiment show that in type III radio bursts, the Langmuir waves often occur as localized magnetic field aligned coherent wave packets with durations of a few ms and with peak intensities well exceeding the strong turbulence thresholds. Some of these wave packets show spectral signatures of beam-resonant Langmuir waves, down- and up-shifted sidebands, and ion sound waves, with frequencies, wave numbers, and tricoherences satisfying the resonance conditions of the oscillating two stream instability (four wave interaction). The spectra of a few of these wave packets also contain peaks at f{sub pe}, 2f{sub pe} and 3 f{sub pe} (f{sub pe} is the electron plasma frequency), with frequencies, wave numbers and bicoherences (computed using the wavelet based bispectral analysis techniques) satisfying the resonance conditions of three wave interactions: (1) excitation of second harmonic electromagnetic waves as a result of coalescence of two oppositely propagating Langmuir waves, and (2) excitation of third harmonic electromagnetic waves as a result of coalescence of Langmuir waves with second harmonic electromagnetic waves. The implication of these findings is that the strong turbulence processes play major roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation in type III radio bursts.

Thejappa, G. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); MacDowall, R. J. [NASA/Goddard Space Flight Center, Greenbelt MD 20771 (United States)

2014-02-11T23:59:59.000Z

435

J. Phys. I IYance 7 (1997) 977-1001 AUGUST 1997, PAGE 977 Phase Pinning by EPR Probe in Biphenyl Doped with  

E-Print Network [OSTI]

J. Phys. I IYance 7 (1997) 977-1001 AUGUST 1997, PAGE 977 Phase Pinning by EPR Probe in Biphenyl not account for the plane wave modulation of the incommen- surate phase II. Its EPR spectra yields a phase is not symmetrical, in contra- diction with a linear one. This behaviour is not exhibited by the phenanthrene EPR

Boyer, Edmond

436

Corrosion monitoring with hydrogen probes in the oilfield  

SciTech Connect (OSTI)

An overview of the application of hydrogen probes for corrosion monitoring in the oilfield is presented. The three basic types of hydrogen probes are described and their relative merits discussed. The construction and installation of a simple and inexpensive electrochemical hydrogen probe is described. Experiences with hydrogen probes in oilfield operations are discussed, and it is concluded from these experiences that production systems where hydrogen probes can provide useful corrosion data are limited.

Thomason, W.H.

1984-05-01T23:59:59.000Z

437

Spectroscopy of triplet states of Rb{sub 2} by femtosecond pump-probe photoionization of doped helium nanodroplets  

SciTech Connect (OSTI)

The dynamics of vibrational wave packets in triplet states of rubidium dimers (Rb{sub 2}) formed on helium nanodroplets are studied using femtosecond pump-probe photoionization spectroscopy. Due to fast desorption of the excited Rb{sub 2} molecules off the droplets and due to their low internal temperature, wave-packet oscillations can be followed up to very long pump-probe delay times > or approx. 1.5 ns. In the first-excited triplet state (1){sup 3}{sigma}{sub g}{sup +}, full and fractional revivals are observed with high contrast. Fourier analysis provides high-resolution vibrational spectra which are in excellent agreement with ab initio calculations.

Mudrich, M.; Heister, Ph.; Hippler, T.; Giese, Ch.; Stienkemeier, F. [Physikalisches Institut, Universitaet Freiburg, 79104 Freiburg (Germany); Dulieu, O. [Laboratoire Aime Cotton, CNRS, Universite Paris-Sud, Batiment 505, 91405 Orsay (France)

2009-10-15T23:59:59.000Z

438

Quantum mechanics of a charged particle in a background magnetic field interacting with linearized gravitational waves  

E-Print Network [OSTI]

We consider the dynamics of a charged particle interacting with background electromagnetic field under the influence of linearized gravitational waves in the long wave-length and low-velocity limit. Following the prescription in \\cite{speli}, the system is quantized and the Hamiltonian is then solved by using standard algebraic iterative methods. The solution is in conformity with the classical analysis and shows the possibility of tuning the frequency by changing the magnetic field to set up resonance.

Sunandan Gangopadhyay; Anirban Saha

2012-04-02T23:59:59.000Z

439

Initial Results in Power System Identification from Injected Probing Signals Using a Subspace Method  

SciTech Connect (OSTI)

In this paper, the authors use the Numerical algorithm for Subspace State Space System IDentification (N4SID) to extract dynamic parameters from phasor measurements collected on the western North American Power Grid. The data were obtained during tests on June 7, 2000, and they represent wide area response to several kinds of probing signals including Low-Level Pseudo-Random Noise (LLPRN) and Single-Mode Square Wave (SMSW) injected at the Celilo terminal of the Pacific HVDC In-tertie (PDCI). An identified model is validated using a cross vali-dation method. Also, the obtained electromechanical modes are compared with the results from Prony analysis of a ringdown and with signal analysis of ambient data measured under similar op-erating conditions. The consistent results show that methods in this class can be highly effective even when the probing signal is small.

Zhou, Ning; Pierre, John W.; Hauer, John F.

2006-08-01T23:59:59.000Z

440

Probing electron acceleration and x-ray emission in laser-plasma accelerators  

SciTech Connect (OSTI)

While laser-plasma accelerators have demonstrated a strong potential in the acceleration of electrons up to giga-electronvolt energies, few experimental tools for studying the acceleration physics have been developed. In this paper, we demonstrate a method for probing the acceleration process. A second laser beam, propagating perpendicular to the main beam, is focused on the gas jet few nanosecond before the main beam creates the accelerating plasma wave. This second beam is intense enough to ionize the gas and form a density depletion, which will locally inhibit the acceleration. The position of the density depletion is scanned along the interaction length to probe the electron injection and acceleration, and the betatron X-ray emission. To illustrate the potential of the method, the variation of the injection position with the plasma density is studied.

Thaury, C.; Ta Phuoc, K.; Corde, S.; Brijesh, P.; Lambert, G.; Malka, V. [Laboratoire d'Optique Appliquée, ENSTA ParisTech—CNRS UMR7639—École Polytechnique ParisTech, Chemin de la Hunière, 91761 Palaiseau (France)] [Laboratoire d'Optique Appliquée, ENSTA ParisTech—CNRS UMR7639—École Polytechnique ParisTech, Chemin de la Hunière, 91761 Palaiseau (France); Mangles, S. P. D.; Bloom, M. S.; Kneip, S. [Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)] [Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)

2013-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" 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

Phase-controlled pulse propagation in media with cross coupling of electric and magnetic probe field component  

SciTech Connect (OSTI)

Light propagation is discussed in media with a cross coupling of the electric and magnetic component of an applied probe field. We derive the wave equations for a probe pulse propagating through such a medium and solve them analytically in Fourier space using the slowly varying envelope approximation. Our analysis reveals the influence of the different medium response coefficients on the propagation dynamics. We apply these results to a specific example system in which cross couplings are induced in an atomic medium by additional control fields. We show that the cross couplings render the propagation dynamics sensitive to the relative phase of the additional fields, and this phase dependence enables one to control the pulse during its propagation through the medium. Our results demonstrate that the magnetic field component of a probe beam can crucially influence the system dynamics already at experimentally accessible parameter ranges in dilute vapors.

Fleischhaker, Robert; Evers, Joerg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

2009-12-15T23:59:59.000Z

442

Detection of azimuthal anisotropy from 3-D p-wave seismic data  

E-Print Network [OSTI]

the equation; (II ? 1) for u(z) = V t(z) is wave slowness. Velocity estimation using reflections and the tau-p approach was first suggested by Schultz and Claerbout (1978), They showed that velocity analysis can be done in a ' similar manner... to conventional analysis by looking for maximum coherency over each ' trajectory of ellipses in r-p domain instead of a hyperbola in conventional analysis. Schultz (1982) also suggested a method of layer-stripping for velocity estimation in the r-p domain...

Yildizel, Ali

1992-01-01T23:59:59.000Z

443

Determination of Surface Exciton Energies by Velocity Resolved...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Exciton Energies by Velocity Resolved Atomic Desorption. Abstract: We have developed a new method for determining surface exciton band energies in alkali halides based on...

444

Note: A helical velocity selector for continuous molecular beams  

SciTech Connect (OSTI)

We report on a modern realization of the classic helical velocity selector for gas phase particle beams. The device operates stably under high vacuum conditions at rotational frequencies limited only by commercial dc motor capabilities. Tuning the rotational frequency allows selective scanning over a broad velocity band. The width of the selected velocity distributions at full-width-half-maximum is as narrow as a few percent of the selected mean velocity and independent of the rotational speed of the selector. The selector generates low vibrational noise amplitudes comparable to mechanically damped state-of-the-art turbo-molecular pumps and is therefore compatible with vibration sensitive experiments like molecule interferometry.

Szewc, Carola; Collier, James D.; Ulbricht, Hendrik [School of Physics and Astronomy, University of Southampton, Highfield, SO17 1BJ (United Kingdom)

2010-10-15T23:59:59.000Z

445

USING MICRO-SEISMICITY AND SEISMIC VELOCITIES TO MAP SUBSURFACE...  

Open Energy Info (EERE)

USING MICRO-SEISMICITY AND SEISMIC VELOCITIES TO MAP SUBSURFACE GEOLOGIC AND HYDROLOGIC STRUCTURE WITHIN THE COSO GEOTHERMAL FIELD, CALIFORNIA Jump to: navigation, search OpenEI...

446

Using Micro-Seismicity and Seismic Velocities to Map Subsurface...  

Open Energy Info (EERE)

OpenEI Reference LibraryAdd to library Conference Paper: Using Micro-Seismicity and Seismic Velocities to Map Subsurface Geologic and Hydrologic Structure Within the Coso...

447

Effective velocities in fractured media: a numerical study using the ...  

E-Print Network [OSTI]

and precise numerical study of effective velocities in fractured structures. ... In this paper, we ..... A final result is that our numerical simulations of P-, SV- and.

2002-03-18T23:59:59.000Z

448

Velocity Interferometer blanking due to preheating in a double pulse planar experiment  

SciTech Connect (OSTI)

Optical diagnostics, such as VISAR (Velocity Interferometer System for Any Reflector) or SOP (Streaked Optical Pyrometry), have become essential in shock timing experiments. Their high precision allows for accurate measurements of shock velocities, chronometry, and brightness temperature. However, in some instances, these measurements can be compromised. In planar shock coalescence experiments recently performed at the LULI facility [Baton et al., Phys. Rev. Lett. 108, 195002 (2012)], VISAR signal loss was observed. In these experiments, a strong shock launched by a high-intensity spike catches up with a previously shock launched by an earlier, low-intensity beam. The disappearance of the VISAR signal is attributed to a preheating of the coronal plasma by x-rays generated by the high intensity spike. The signal does not disappear if the high-intensity spike starts after VISAR probe beam begins to reflect off of the first shock. The VISAR diagnostic, modeled using an assessment of the optical index in quartz, compares favorably to experimental results. This provides evidence that x-ray preheating can cause blanking of the VISAR signal in quartz.

Laffite, S.; Combis, P.; Clerouin, J.; Recoules, V.; Rousseaux, C.; Videau, L. [CEA, DAM, DIF, F-91297 Arpajon (France); Baton, S. D.; Koenig, M. [LULI, Ecole Polytechnique, CNRS, CEA, UPMC, route de Saclay, 91128 Palaiseau (France)

2014-08-15T23:59:59.000Z

449

Analyzing intramolecular vibrational energy redistribution via the overlap intensity-level velocity correlator  

E-Print Network [OSTI]

Numerous experimental and theoretical studies have established that intramolecular vibrational energy redistribution (IVR) in isolated molecules has a heirarchical tier structure. The tier structure implies strong correlations between the energy level motions of a quantum system and its intensity-weighted spectrum. A measure, which explicitly accounts for this correaltion, was first introduced by one of us as a sensitive probe of phase space localization. It correlates eigenlevel velocities with the overlap intensities between the eigenstates and some localized state of interest. A semiclassical theory for the correlation is developed for systems that are classically integrable and complements earlier work focusing exclusively on the chaotic case. Application to a model two dimensional effective spectroscopic Hamiltonian shows that the correlation measure can provide information about the terms in the molecular Hamiltonian which play an important role in an energy range of interest and the character of the dynamics. Moreover, the correlation function is capable of highlighting relevant phase space structures including the local resonance features associated with a specific bright state. In addition to being ideally suited for multidimensional systems with a large density of states, the measure can also be used to gain insights into the phase space transport and localization. It is argued that the overlap intensity-level velocity correlation function provides a novel way of studying vibrational energy redistribution in isolated molecules. The correlation function is ideally suited to analyzing the parametric spectra of molecules in external fields.

Srihari Keshavamurthy; Nicholas R. Cerruti; Steven Tomsovic

2002-02-02T23:59:59.000Z

450

Full wave simulations of lower hybrid wave propagation in tokamaks  

E-Print Network [OSTI]

Full wave simulations of lower hybrid wave propagation in tokamaks J. C. Wright , P. T. Bonoli , C hybrid (LH) waves have the attractive property of damping strongly via electron Landau resonance. Consequently these waves are well-suited to driving current in the plasma periphery where the electron

Wright, John C.

451

SEISMIC WAVES ESTIMATION AND WAVE FIELD DECOMPOSITION WITH FACTOR GRAPHS  

E-Print Network [OSTI]

SEISMIC WAVES ESTIMATION AND WAVE FIELD DECOMPOSITION WITH FACTOR GRAPHS Stefano Maranò Christoph, Dept. Information Technology & Electr. Eng., 8092 Zürich ABSTRACT Physical wave fields are often from sensors of different kinds. In this paper we propose a technique for the analysis of vector wave

Loeliger, Hans-Andrea

452

Taming water waves Case study: Surface Water Waves  

E-Print Network [OSTI]

Taming water waves Case study: Surface Water Waves Few things in nature are as dramatic, and potentially dangerous, as ocean waves. The impact they have on our daily lives extends from shipping to the role they play in driving the global climate. From a theoretical viewpoint water waves pose rich

453

Selfconsistent full wave simulations of lower hybrid waves  

E-Print Network [OSTI]

Selfconsistent full wave simulations of lower hybrid waves John C. Wright P. T. Bonoli MIT E .J. Porkolab Sherwood/Spring APS Denver May 2009 #12; 2 Participants in the Center for Simulation of Wave hybrid (LH) waves have the attractive property of damping strongly via electron Landau resonance

Wright, John C.

454

On Generating Gravity Waves with Matter and Electromagnetic Waves  

E-Print Network [OSTI]

If a homogeneous plane light-like shell collides head-on with a homogeneous plane electromagnetic shock wave having a step-function profile then no backscattered gravitational waves are produced. We demonstrate, by explicit calculation, that if the matter is accompanied by a homogeneous plane electromagnetic shock wave with a step-function profile then backscattered gravitational waves appear after the collision.

C. Barrabes; P. A. Hogan

2008-04-05T23:59:59.000Z

455

Nonlinear peculiar-velocity analysis and PCA  

SciTech Connect (OSTI)

We allow for nonlinear effects in the likelihood analysis of peculiar velocities, and obtain {approximately}35%-lower values for the cosmological density parameter and for the amplitude of mass-density fluctuations. The power spectrum in the linear regime is assumed to be of the flat {Lambda}CDM model (h = 0:65, n = 1) with only {Omega}{sub m} free. Since the likelihood is driven by the nonlinear regime, we break the power spectrum at k{sub b} {approximately} 0.2 (h{sup {minus}1} Mpc){sup {minus}1} and fit a two-parameter power-law at k > k{sub b} . This allows for an unbiased fit in the linear regime. Tests using improved mock catalogs demonstrate a reduced bias and a better fit. We find for the Mark III and SFI data {Omega}{sub m} = 0.35 {+-} 0.09 with {sigma}{sub 8}{Omega}P{sub m}{sup 0.6} = 0.55 {+-} 0.10 (90% errors). When allowing deviations from {Lambda}CDM, we find an indication for a wiggle in the power spectrum in the form of an excess near k {approximately} 0.05 and a deficiency at k {approximately} 0.1 (h{sup {minus}1} Mpc){sup {minus}1}--a cold flow which may be related to a feature indicated from redshift surveys and the second peak in the CMB anisotropy. A {chi}{sup 2} test applied to principal modes demonstrates that the nonlinear procedure improves the goodness of fit. The Principal Component Analysis (PCA) helps identifying spatial features of the data and fine-tuning the theoretical and error models. We address the potential for optimal data compression using PCA.

Dekel, A. [and others

2001-02-20T23:59:59.000Z

456

Surface wave interferometry   

E-Print Network [OSTI]

This thesis concerns the application of seismic interferometry to surface waves. Seismic interferometry is the process by which the wavefield between two recording locations is estimated, resulting in new recordings at ...

Halliday, David Fraser

2009-01-01T23:59:59.000Z

457

Fireside corrosion probes--an update  

SciTech Connect (OSTI)

The ability to monitor the corrosion degradation of key metallic components in fossil fuel power plants will become increasingly important for FutureGen and ultra-supercritical power plants. A number of factors (ash deposition, coal composition changes, thermal gradients, and low NOx conditions, among others) which occur in the high temperature sections of energy production facilities, will contribute to fireside corrosion. Several years of research have shown that high temperature corrosion rate probes need to be better understood before corrosion rate can be used as a process variable by power plant operators. Our recent research has shown that electrochemical corrosion probes typically measure lower corrosion rates than those measured by standard mass loss techniques. While still useful for monitoring changes in corrosion rates, absolute probe corrosion rates will need a calibration factor to be useful. Continuing research is targeted to help resolve these issues.

Covino, B.S., Jr.; Bullard, S.J.; Holcomb, G.R.; Ziomek-Moroz, M.; Matthes, S.A.

2007-01-01T23:59:59.000Z

458

Gamma-ray blind beta particle probe  

DOE Patents [OSTI]

An intra-operative beta particle probe is provided by placing a suitable photomultiplier tube (PMT), micro channel plate (MCP) or other electron multiplier device within a vacuum housing equipped with: 1) an appropriate beta particle permeable window; and 2) electron detection circuitry. Beta particles emitted in the immediate vicinity of the probe window will be received by the electron multiplier device and amplified to produce a detectable signal. Such a device is useful as a gamma insensitive, intra-operative, beta particle probe in surgeries where the patient has been injected with a beta emitting radiopharmaceutical. The method of use of such a device is also described, as is a position sensitive such device.

Weisenberger, Andrew G. (Grafton, VA)

2001-01-01T23:59:59.000Z

459

Remote adjustable focus Raman spectroscopy probe  

DOE Patents [OSTI]

A remote adjustable focus Raman spectroscopy probe allows for analyzing Raman scattered light from a point of interest external probe. An environmental barrier including at least one window separates the probe from the point of interest. An optical tube is disposed adjacent to the environmental barrier and includes a long working length compound lens objective next to the window. A beam splitter and a mirror are at the other end. A mechanical means is used to translated the prove body in the X, Y, and Z directions resulting in a variable focus optical apparatus. Laser light is reflected by the beam splitter and directed toward the compound lens objective, then through the window and focused on the point of interest. Raman scattered light is then collected by the compound lens objective and directed through the beam splitter to a mirror. A device for analyzing the light, such as a monochrometer, is coupled to the mirror.

Schmucker, John E. (Hurt, VA); Blasi, Raymond J. (Harrison City, PA); Archer, William B. (Bethel Park, PA)

1999-01-01T23:59:59.000Z

460

Eulerian simulations of collisional effects on electrostatic plasma waves  

SciTech Connect (OSTI)

The problem of collisions in a plasma is a wide subject with a huge historical literature. In fact, the description of realistic plasmas is a tough problem to attack, both from the theoretical and the numerical point of view. In this paper, a Eulerian time-splitting algorithm for the study of the propagation of electrostatic waves in collisional plasmas is presented. Collisions are modeled through one-dimensional operators of the Fokker-Planck type, both in linear and nonlinear forms. The accuracy of the numerical code is discussed by comparing the numerical results to the analytical predictions obtained in some limit cases when trying to evaluate the effects of collisions in the phenomenon of wave plasma echo and collisional dissipation of Bernstein-Greene-Kruskal waves. Particular attention is devoted to the study of the nonlinear Dougherty collisional operator, recently used to describe the collisional dissipation of electron plasma waves in a pure electron plasma column [M. W. Anderson and T. M. O'Neil, Phys. Plasmas 14, 112110 (2007)]. Finally, for the study of collisional plasmas, a recipe to set the simulation parameters in order to prevent the filamentation problem can be provided, by exploiting the property of velocity diffusion operators to smooth out small velocity scales.

Pezzi, Oreste; Valentini, Francesco; Perrone, Denise; Veltri, Pierluigi [Dipartimento di Fisica and CNISM, Università della Calabria, 87036 Rende (CS) (Italy)] [Dipartimento di Fisica and CNISM, Università della Calabria, 87036 Rende (CS) (Italy)

2013-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "velocity wave probe" from the National Library of EnergyBeta (NLEBeta).
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461

Experimental observation of standing wave effect in low-pressure very-high-frequency capacitive discharges  

SciTech Connect (OSTI)

Radial uniformity measurements of plasma density were carried out by using a floating double probe in a cylindrical (21?cm in electrode diameter) capacitive discharge reactor driven over a wide range of frequencies (27–220 MHz). At low rf power, a multiple-node structure of standing wave effect was observed at 130?MHz. The secondary density peak caused by the standing wave effect became pronounced and shifts toward the axis as the driving frequency further to increase, indicative of a much more shortened standing-wave wavelength. With increasing rf power, the secondary density peak shift toward the radial edge, namely, the standing-wave wavelength was increased, in good qualitative agreement with the previous theory and simulation results. At higher pressures and high frequencies, the rf power was primarily deposited at the periphery of the electrode, due to the fact that the waves were strongly damped as they propagated from the discharge edge into the center.

Liu, Yong-Xin; Gao, Fei; Liu, Jia; Wang, You-Nian, E-mail: ynwang@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

2014-07-28T23:59:59.000Z

462

WaveBob (TRL 5 6 System) - Advanced Wave Energy Conversion Project...  

Broader source: Energy.gov (indexed) [DOE]

WaveBob (TRL 5 6 System) - Advanced Wave Energy Conversion Project WaveBob (TRL 5 6 System) - Advanced Wave Energy Conversion Project WaveBob (TRL 5 6 System) - Advanced Wave...

463

Estimation of scalar moments from explosion-generated surface waves  

SciTech Connect (OSTI)

Rayleigh waves from underground nuclear explosions are used to estimate scaler moments for 40 Nevada Test Site (NTS) explosions and 18 explosions at the Soviet East Kazakh test site. The Rayleigh wave spectrum is written as a product of functions that depend on the elastic structure of the travel path, the elastic structure of the source region and the Q structure of the path. Results are used to examine the worldwide variability of each factor and the resulting variability of surface wave amplitudes. The path elastic structure and Q structure are found by inversion of Rayleigh wave phase and group velocities and spectral amplitudes. The Green's function derived from this structure is used to estimate the moments of explosions observed along the same path. This procedure produces more consistent amplitude estimates than conventional magnitude measurements. Network scatter in log moment is typically 0.1. In contrast with time-domain amplitudes, the elastic structure of the travel path causes little variability in spectral amplitudes. When the mantle Q is constrained to a value of approximately 100 at depths greater than 120 km, the inversion for Q and moment produces moments that remain constant with distance. Based on the best models available, surface waves from NTS explosions should be larger than surface waves from East Kazakh explosions with the same moment. Estimated scaler moments for the largest East Kazakh explosions since 1976 are smaller than the estimated moments for the largest NTS explosions for the same time period.

Stevens, J.L.

1985-04-01T23:59:59.000Z

464

ENERGY CONTENT AND PROPAGATION IN TRANSVERSE SOLAR ATMOSPHERIC WAVES  

SciTech Connect (OSTI)

Recently, a significant amount of transverse wave energy has been estimated propagating along solar atmospheric magnetic fields. However, these estimates have been made with the classic bulk Alfven wave model which assumes a homogeneous plasma. In this paper, the kinetic, magnetic, and total energy densities and the flux of energy are computed for transverse MHD waves in one-dimensional cylindrical flux tube models with a piecewise constant or continuous radial density profile. There are fundamental deviations from the properties for classic bulk Alfven waves. (1) There is no local equipartition between kinetic and magnetic energy. (2) The flux of energy and the velocity of energy transfer have, in addition to a component parallel to the magnetic field, components in the planes normal to the magnetic field. (3) The energy densities and the flux of energy vary spatially, contrary to the case of classic bulk Alfven waves. This last property has the important consequence that the energy flux computed with the well known expression for bulk Alfven waves could overestimate the real flux by a factor in the range 10-50, depending on the flux tube equilibrium properties.

Goossens, M.; Van Doorsselaere, T. [Centre for mathematical Plasma Astrophysics, Mathematics Department, Celestijnenlaan 200B bus 2400, B-3001 Heverlee (Belgium); Soler, R. [Solar Physics Group, Departament de Fisica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Verth, G., E-mail: tom.vandoorsselaere@wis.kuleuven.be [Solar Physics and Space Plasma Research Centre (SP2RC), School of Mathematics and Statistics, University of Sheffield, Hounsfield Road, Hicks Building, Sheffield S3 7RH (United Kingdom)

2013-05-10T23:59:59.000Z

465

Single crystal metal wedges for surface acoustic wave propagation  

DOE Patents [OSTI]

An ultrasonic testing device has been developed to evaluate flaws and inhomogeneities in the near-surface region of a test material. A metal single crystal wedge is used to generate high frequency Rayleigh surface waves in the test material surface by conversion of a slow velocity, bulk acoustic mode in the wedge into a Rayleigh wave at the metal-wedge test material interface. Particular classes of metals have been found to provide the bulk acoustic modes necessary for production of a surface wave with extremely high frequency and angular collimation. The high frequency allows flaws and inhomogeneities to be examined with greater resolution. The high degree of angular collimation for the outgoing ultrasonic beam permits precision angular location of flaws and inhomogeneities in the test material surface.

Fisher, E.S.

1980-05-09T23:59:59.000Z

466

Langasite Surface Acoustic Wave Gas Sensors: Modeling and Verification  

SciTech Connect (OSTI)

We report finite element simulations of the effect of conductive sensing layers on the surface wave velocity of langasite substrates. The simulations include both the mechanical and electrical influences of the conducting sensing layer. We show that three-dimensional simulations are necessary because of the out-of-plane displacements of the commonly used (0, 138.5, 26.7) Euler angle. Measurements of the transducer input admittance in reflective delay-line devices yield a value for the electromechanical coupling coefficient that is in good agreement with the three-dimensional simulations on bare langasite substrate. The input admittance measurements also show evidence of excitation of an additional wave mode and excess loss due to the finger resistance. The results of these simulations and measurements will be useful in the design of surface acoustic wave gas sensors.

Zheng, Peng; Greve, David W.; Oppenheim, Irving J.

2013-01-01T23:59:59.000Z

467

Single crystal metal wedges for surface acoustic wave propagation  

DOE Patents [OSTI]

An ultrasonic testing device has been developed to evaluate flaws and inhomogeneities in the near-surface region of a test material. A metal single crystal wedge is used to generate high frequency Rayleigh surface waves in the test material surface by conversion of a slow velocity, bulk acoustic mode in the wedge into a Rayleigh wave at the metal-wedge test material interface. Particular classes of metals have been found to provide the bulk acoustic modes necessary for production of a surface wave with extremely high frequency and angular collimation. The high frequency allows flaws and inhomogeneities to be examined with greater resolution. The high degree of angular collimation for the outgoing ultrasonic beam permits precision angular location of flaws and inhomogeneities in the test material surface.

Fisher, Edward S. (Wheaton, IL)

1982-01-01T23:59:59.000Z

468

Mathematical Caricature of Large Waves  

E-Print Network [OSTI]

The Kadomtsev-Petviiashvili equation is considered as a mathematical caricature of large and rogue waves.

Mikhail Kovalyov

2014-03-21T23:59:59.000Z

469

Clustering of floaters by waves  

E-Print Network [OSTI]

We study experimentally how waves affect distribution of particles that float on a water surface. We show that clustering of small particles in a standing wave is a nonlinear effect with the clustering time decreasing as the square of the wave amplitude. In a set of random waves, we show that small floaters concentrate on a multi-fractal set.

P. Denissenko; G. Falkovich; S. Lukaschuk

2005-11-22T23:59:59.000Z

470

December 2010 | 23 GUIDED WAVES  

E-Print Network [OSTI]

December 2010 | 23 GUIDED WAVES Tuning Wave Dispersion in Resonant Networks Eyal Feigenbaum with meta-atoms. Resonant guided wave networks (RGWNs) are a new class of artificial photonic material,5 distinct from photonic crystals and metamateri- als, in which localized waves resonate in closed paths

Atwater, Harry

471

Autoresonant Excitation of Diocotron Waves  

E-Print Network [OSTI]

of the wave, the pump and the wave will phase lock at very low wave amplitude. When the pump reachesAutoresonant Excitation of Diocotron Waves J. Fajans E. Gilson U.C. Berkeley L. Friedland Hebrew of phase with the oscillator, and the os- cillator's amplitude will decrease, eventually reaching zero

Wurtele, Jonathan

472

Scintillation probe with photomultiplier tube saturation indicator  

DOE Patents [OSTI]

A photomultiplier tube saturation indicator is formed by supplying a supplemental light source, typically an light emitting diode (LED), adjacent to the photomultiplier tube. A switch allows the light source to be activated. The light is forwarded to the photomultiplier tube by an optical fiber. If the probe is properly light tight, then a meter attached to the indicator will register the light from the LED. If the probe is no longer light tight, and the saturation indicator is saturated, no signal will be registered when the LED is activated.

Ruch, Jeffrey F. (Bethel Park, PA); Urban, David J. (Glassport, PA)

1996-01-01T23:59:59.000Z

473

Multiple-frequency acoustic wave devices for chemical sensing and materials characterization in both gas and liquid phase  

DOE Patents [OSTI]

A chemical or intrinsic physical property sensor is described comprising: (a) a substrate; (b) an interaction region of said substrate where the presence of a chemical or physical stimulus causes a detectable change in the velocity and/or an attenuation of an acoustic wave traversing said region; and (c) a plurality of paired input and output interdigitated electrodes patterned on the surface of said substrate where each of said paired electrodes has a distinct periodicity, where each of said paired electrodes is compri