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1

Airborne Gravity Survey | Open Energy Information  

Open Energy Info (EERE)

Airborne Gravity Survey Airborne Gravity Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Airborne Gravity Survey Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Gravity Techniques Parent Exploration Technique: Gravity Techniques Information Provided by Technique Lithology: Distribution of density in the subsurface enables inference of rock type. Stratigraphic/Structural: Delineation of steeply dipping formations, geological discontinuities and faults, intrusions and the deposition of silicates due to hydrothermal activity. Hydrological: Density of sedimentary rocks are strongly influenced by fluid contained within pore space. Dry bulk density refers to the rock with no moisture, while the wet bulk density accounts for water saturation; fluid content may alter density by up to 30%.(Sharma, 1997)

2

Definition: Airborne Gravity Survey | Open Energy Information  

Open Energy Info (EERE)

Survey Jump to: navigation, search Dictionary.png Airborne Gravity Survey Airborne gravity gradiometry (AGG) surveys provide information regarding the mass distribution of the...

3

Category:Gravity Techniques | Open Energy Information  

Open Energy Info (EERE)

Techniques page? For detailed information on Gravity Techniques, click here. Category:Gravity Techniques Add.png Add a new Gravity Techniques Technique Pages in category "Gravity...

4

Airborne electromagnetic surveys as a reconnaissance technique...  

Open Energy Info (EERE)

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

5

Gravity Techniques | Open Energy Information  

Open Energy Info (EERE)

Gravity Techniques Gravity Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Gravity Techniques Details Activities (0) Areas (0) Regions (0) NEPA(1) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Gravity Techniques Parent Exploration Technique: Geophysical Techniques Information Provided by Technique Lithology: Distribution of density in the subsurface enables inference of rock type. Stratigraphic/Structural: Delineation of steeply dipping formations, geological discontinuities and faults, intrusions and the deposition of silicates due to hydrothermal activity. Hydrological: Density of sedimentary rocks are strongly influenced by fluid contained within pore space. Dry bulk density refers to the rock with no moisture, while the wet bulk density accounts for water saturation; fluid content may alter density by up to 30%.(Sharma, 1997)

6

Definition: Gravity Techniques | Open Energy Information  

Open Energy Info (EERE)

0521576326 Ret LikeLike UnlikeLike You like this.Sign Up to see what your friends like. rieved from "http:en.openei.orgwindex.php?titleDefinition:GravityTechniques&oldid598...

7

Airborne electromagnetic surveys as a reconnaissance technique for  

Open Energy Info (EERE)

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

8

A Comparison of Near-Infrared Diode Laser Techniques for Airborne Hygrometry  

Science Conference Proceedings (OSTI)

High-frequency wavelength modulation spectroscopy and dual beam absorption noise canceler methods are compared for near-infrared laser detection of moisture at levels relevant to airborne hygrometry. Both techniques exhibit sensitivities ...

Joel A. Silver; David Christian Hovde

1998-02-01T23:59:59.000Z

9

Effect of Centrifugal And Gravity Casting Technique over ...  

Science Conference Proceedings (OSTI)

In this work an attempt is made to study the effect of centrifugal and gravity casting ... A Minimum Pollution, Low Energy Process for the Recovery of Cobalt and ...

10

Development of an ultrasonic technique to measure specfic gravity in lead-acid battery electrolyte  

DOE Green Energy (OSTI)

An ultrasonic technique to measure specific gravity in lead-acid battery electrolyte is described in detail. This technique, which is based on the theory that the velocity of sound in a liquid depends on the density of the liquid, compares the ultrasonically measured velocity of sound in battery electrolyte (derived by measuring the time required for sound to traverse a known distance of electrolyte) to velocities in a computer-stored data base relating velocity, density, and temperature. The experimental design, the data base developed for the method, a laboratory feasibility study, and an error analysis of the study are discussed. The major advantages of the method are 1) the passive nature of the measurement, 2) the continuous sample and display capabilities, 3) the instantaneous tracking of changes in specific gravity, and 4) inherent averaging of the specific gravity measurements.

Swoboda, C.A.; Cannon, P.H.; Fredrickson, D.R.; Gabelnick, S.D.; Hornstra, F.; Phan, K.A.; Singleterry; Yao, N.P.

1983-03-01T23:59:59.000Z

11

Comparison of airborne asbestos levels determined by transmission electron microscopy (TEM) using direct- and indirect-transfer techniques. Final report  

SciTech Connect

A subset of air samples from a 1988 EPA study was reanalyzed for asbestos by TEM using an indirect transfer technique. The samples were originally analyzed using a direct transfer technique. The document presents the results of the reanalysis and extends the discussion to include data from six other studies. The development of the two techniques and their respective advantages and disadvantages are described. The data support the general opinion that TEM analysis of air samples using indirect transfer methods tends to provide estimates of total airborne asbestos structure concentration that are higher than those obtained using direct transfer methods. There is no single factor that can be used to convert measurements made by one method to a value that is comparable with measurements made by the other because the quantitative relationship is expected to depend on details of the sampling and analytical protocols and the nature of the asbestos in the air. The ratio of indirect measurements to direct measurements ranges from 3.8 to 1,700 for the studies considered. Additional research is needed to determine which transfer technique more accurately reflects biologically meaningful airborne asbestos concentrations. Breakdown of larger structures into smaller ones during indirect preparation does not appear to be sufficient to explain the difference in measured concentrations.

Chesson, J.; Hatfield, J.

1990-03-01T23:59:59.000Z

12

VLBI FOR GRAVITY PROBE B. IV. A NEW ASTROMETRIC ANALYSIS TECHNIQUE AND A COMPARISON WITH RESULTS FROM OTHER TECHNIQUES  

Science Conference Proceedings (OSTI)

When very long baseline interferometry (VLBI) observations are used to determine the position or motion of a radio source relative to reference sources nearby on the sky, the astrometric information is usually obtained via (1) phase-referenced maps or (2) parametric model fits to measured fringe phases or multiband delays. In this paper, we describe a 'merged' analysis technique which combines some of the most important advantages of these other two approaches. In particular, our merged technique combines the superior model-correction capabilities of parametric model fits with the ability of phase-referenced maps to yield astrometric measurements of sources that are too weak to be used in parametric model fits. We compare the results from this merged technique with the results from phase-referenced maps and from parametric model fits in the analysis of astrometric VLBI observations of the radio-bright star IM Pegasi (HR 8703) and the radio source B2252+172 nearby on the sky. In these studies we use central-core components of radio sources 3C 454.3 and B2250+194 as our positional references. We obtain astrometric results for IM Peg with our merged technique even when the source is too weak to be used in parametric model fits, and we find that our merged technique yields astrometric results superior to the phase-referenced mapping technique. We used our merged technique to estimate the proper motion and other astrometric parameters of IM Peg in support of the NASA/Stanford Gravity Probe B mission.

Lebach, D. E.; Ratner, M. I.; Shapiro, I. I. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Bartel, N.; Bietenholz, M. F.; Lederman, J. I.; Ransom, R. R. [Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, ON M3J 1P3 (Canada); Campbell, R. M. [Joint Institute for VLBI in Europe, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo (Netherlands); Gordon, D. [NVI Inc./NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Lestrade, J.-F. [Observatoire de Paris, Centre National de la Recherche Scientifique, 77 Av. Denfert Rochereau, 75014 Paris (France)

2012-07-01T23:59:59.000Z

13

Karst characterization in a semi-arid region using gravity, seismic, and resistivity geophysical techniques.  

SciTech Connect

We proposed to customize emerging in situ geophysical monitoring technology to generate time-series data during sporadic rain events in a semi-arid region. Electrodes were to be connected to wireless %5Cnodes%22 which can be left in the eld for many months. Embedded software would then increase sampling frequency during periods of rainfall. We hypothesized that this contrast between no-volume ow in karst passageways dur- ing dry periods and partial- or saturated-volume ow during a rain event is detectable by these Wireless Sensor Network (WSN) geophysical nodes, we call this a Wireless Resistivity Network (WRN). The development of new methodologies to characterize semi-arid karst hydrology is intended to augment Sandia National Laboratorys mission to lead e orts in energy technologies, waste disposal and climate security by helping to identify safe and secure regions and those that are at risk. Development and initial eld testing identi ed technological barriers to using WRNs for identifying semi-arid karst, exposing R&D which can be targeted in the future. Gravity, seismic, and resis- tivity surveys elucidated how each technique might e ectively be used to characterize semi-arid karst. This research brings to light the importance and challenges with char- acterizing semi-arid karst through a multi-method geophysical study. As there have been very few studies with this emphasis, this study has expanded the body of practical experience needed to protect the nations water and energy security interests.

Barnhart, Kevin Scott

2013-10-01T23:59:59.000Z

14

Three dimensional gravity modeling techniques with application to the Ennis Geothermal Area: Final report: Part 1  

DOE Green Energy (OSTI)

3-D gravity modeling was done in the area of the Ennis hot spring in an attempt to determine controlling structure of the Ennis hot spring. The modeling was done in a two-step process where: 1) The topography was modeled by modeling the valley fill from the highest elevation in the modeling area to some elevation below the lowest station elevation using Talwani and Ewing's (1960) method of modeling with vertically-stacked, horizontal, n-sided polygons. Once the gravity contributions of the valley fill included in this ''topographic model'' are calculated, they were removed from the original gravity data; 2) The remaining valley fill was modeled using blocks where the 3-D algorithm for modeling with blocks results from integrating the gravity formula in the X and Z directions and approximating the integration in the Y-direction using a quadrature formula. Finally, an inverse 3-D gravity modeling program was written to automatically adjust the bedrock topography output from this two-step modeling process. The gravity data calculated from the adjusted bedrock topography, output from the inverse modeling program, should match the observed gravity data within the error of the survey. 43 refs., 40 figs., 9 tabs.

Semmens, D.

1987-12-01T23:59:59.000Z

15

A Novel Two-Step Laser Ranging Technique for a Precision Test of the Theory of Gravity  

E-Print Network (OSTI)

All powered spacecraft experience residual systematic acceleration due to anisotropy of the thermal radiation pressure and fuel leakage. The residual acceleration limits the accuracy of any test of gravity that relies on the precise determination of the spacecraft trajectory. We describe a novel two-step laser ranging technique, which largely eliminates the effects of non-gravity acceleration sources and enables celestial mechanics checks with unprecedented precision. A passive proof mass is released from the mother spacecraft on a solar system exploration mission. Retro-reflectors attached to the proof mass allow its relative position to the spacecraft to be determined using optical ranging techniques. Meanwhile, the position of the spacecraft relative to the Earth is determined by ranging with a laser transponder. The vector sum of the two is the position, relative to the Earth, of the proof mass, the measurement of which is not affected by the residual accelerations of the mother spacecraft. We also describe the mission concept of the Dark Matter Explorers (DMX), which will demonstrate this technology and will use it to test the hypothesis that dark matter congregates around the sun. This hypothesis implies a small apparent deviation from the inverse square law of gravity, which can be detected by a sensitive experiment. We expect to achieve an acceleration resolution of $\\sim 10^{-14} m/s^2$. DMX will also be sensitive to acceleration towards the galactic center, which has a value of $\\sim 10^{-10} m/s^2$. Since dark matter dominates the galactic acceleration, DMX can also test whether dark matter obeys the equivalence principle to a level of 100 ppm by ranging to several proof masses of different composition from the mother spacecraft.

Konstantin Penanen; Talso Chui

2004-06-04T23:59:59.000Z

16

Ground Gravity Survey At Lightning Dock Area (Warpinski, Et Al., 2002) |  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Ground Gravity Survey At Lightning Dock Area (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Lightning Dock Area (Warpinski, Et Al., 2002) Exploration Activity Details Location Lightning Dock Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes As a foundation for successful siting and drilling a deep test well, additional geophysical work has been completed including gravity, resistivity, and airborne magnetic surveys. Several new seismic profiles

17

Massive Gravity  

E-Print Network (OSTI)

We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali-Gabadadze-Porrati model, cascading gravity and ghost-free massive gravity. We then explore their theoretical and phenomenological consistency, proving the absence of Boulware-Deser ghosts and reviewing the Vainshtein mechanism and the cosmological solutions in these models. Finally we present alternative and related models of massive gravity such as new massive gravity, Lorentz-violating massive gravity and non-local massive gravity.

de Rham, Claudia

2014-01-01T23:59:59.000Z

18

Massive Gravity  

E-Print Network (OSTI)

We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali-Gabadadze-Porrati model, cascading gravity and ghost-free massive gravity. We then explore their theoretical and phenomenological consistency, proving the absence of Boulware-Deser ghosts and reviewing the Vainshtein mechanism and the cosmological solutions in these models. Finally we present alternative and related models of massive gravity such as new massive gravity, Lorentz-violating massive gravity and non-local massive gravity.

Claudia de Rham

2014-01-16T23:59:59.000Z

19

Gravity Methods | Open Energy Information  

Open Energy Info (EERE)

Gravity Methods Gravity Methods Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Gravity Methods Details Activities (0) Areas (0) Regions (0) NEPA(3) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Gravity Techniques Parent Exploration Technique: Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Gravity Methods: No definition has been provided for this term. Add a Definition References No exploration activities found. Document # Analysis Type Applicant Geothermal Area Lead Agency District Office Field Office Mineral Manager Surface Manager Development Phase(s) Techniques NVN-084630 CU Vulcan Energy Patua Geothermal Area BLM Nevada State Office BLM Winnemucca District Office BLM Humboldt River Field Office BLM BLM Geothermal/Exploration Gravity Methods

20

Airborne Electromagnetic Survey | Open Energy Information  

Open Energy Info (EERE)

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

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Ground Gravity Survey At Dixie Valley Geothermal Field Area ...  

Open Energy Info (EERE)

Details Location Dixie Valley Geothermal Field Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes The gravity data are...

22

Ground Gravity Survey At Marysville Mt Area (Blackwell) | Open...  

Open Energy Info (EERE)

Ground Gravity Survey At Marysville Mt Area (Blackwell) Exploration Activity Details Location Marysville Mt Area Exploration Technique Ground Gravity Survey Activity Date...

23

Massive gravity from bimetric gravity  

E-Print Network (OSTI)

We discuss the subtle relationship between so-called massive gravity (that is, gravity incorporating a non-zero graviton mass) and bimetric gravity, focussing particularly on the manner in which massive gravity may be viewed as a suitable limit of bimetric gravity. The limiting procedure is more delicate than currently appreciated, and in particular, in a cosmological context can lead to an interesting interplay between the "background" and "foreground" metrics. The fact that in bimetric theories one always has two sets of metric equations of motion, one for each metric, continues to have an effect even in the massive gravity limit. Thus, solutions of bimetric gravity in the limit of vanishing kinetic term are also solutions of massive gravity, but the contrary statement is not necessarily true.

Baccetti, Valentina; Visser, Matt

2012-01-01T23:59:59.000Z

24

Liouville gravity from Einstein gravity  

E-Print Network (OSTI)

We show that Liouville gravity arises as the limit of pure Einstein gravity in 2+epsilon dimensions as epsilon goes to zero, provided Newton's constant scales with epsilon. Our procedure - spherical reduction, dualization, limit, dualizing back - passes several consistency tests: geometric properties, interactions with matter and the Bekenstein-Hawking entropy are as expected from Einstein gravity.

D. Grumiller; R. Jackiw

2007-12-21T23:59:59.000Z

25

Fast Temperature and True Airspeed Measurements with the Airborne Ultrasonic Anemometer–Thermometer (AUSAT)  

Science Conference Proceedings (OSTI)

An airborne thermometer–anemometer with fast response is designed and built using the well-known sonic anemometer–thermometer technique. The shape of this new airborne sonic sensor, without the conventional style probes, is a cylinder with its ...

D. Cruette; A. Marillier; J. L. Dufresne; J. Y. Grandpeix; P. Nacass; H. Bellec

2000-08-01T23:59:59.000Z

26

Einstein Gravity from Conformal Gravity  

E-Print Network (OSTI)

We show that that four dimensional conformal gravity plus a simple Neumann boundary condition can be used to get the semiclassical (or tree level) wavefunction of the universe of four dimensional asymptotically de-Sitter or Euclidean anti-de Sitter spacetimes. This simple Neumann boundary condition selects the Einstein solution out of the more numerous solutions of conformal gravity. It thus removes the ghosts of conformal gravity from this computation. In the case of a five dimensional pure gravity theory with a positive cosmological constant we show that the late time superhorizon tree level probability measure, $|\\Psi [ g ]|^2$, for its four dimensional spatial slices is given by the action of Euclidean four dimensional conformal gravity.

Juan Maldacena

2011-05-27T23:59:59.000Z

27

Gravity brake  

DOE Patents (OSTI)

A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.

Lujan, Richard E. (Santa Fe, NM)

2001-01-01T23:59:59.000Z

28

Airborne Tracking Sunphotometer  

Science Conference Proceedings (OSTI)

An airborne tracking sunphotometer, mounted on the outside top surface of an aircraft has been developed to provide unrestricted viewing of the Sun. This instrument will substantially increase the data that scientists can gather for atmospheric ...

Tak Matsumoto; Philip Russell; Cesar Mina; William Van Ark; Victor Banta

1987-06-01T23:59:59.000Z

29

Airborne Internet : market & opportunity  

E-Print Network (OSTI)

The purpose of this thesis to evaluate the opportunity for service provider entry and of the airborne internet, to analyze the disruptive impact technology used by AirCell and AeroSat has had on the development of an ...

Bhadouria, Anand

2007-01-01T23:59:59.000Z

30

Ground Gravity Survey | Open Energy Information  

Open Energy Info (EERE)

Ground Gravity Survey Ground Gravity Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Ground Gravity Survey Details Activities (48) Areas (34) Regions (2) NEPA(2) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Gravity Techniques Parent Exploration Technique: Gravity Techniques Information Provided by Technique Lithology: Distribution of density in the subsurface enables inference of rock type. Stratigraphic/Structural: Delineation of steeply dipping formations, geological discontinuities and faults, intrusions and large-scale deposition of silicates due to hydrothermal activity. Hydrological: Density of sedimentary rocks are strongly influenced by fluid contained within pore space. Dry bulk density refers to the rock with no moisture, while the wet bulk density accounts for water saturation; fluid content may alter density by up to 30%.(Sharma, 1997)

31

Gravity quantized: Loop quantum gravity with a scalar field  

Science Conference Proceedings (OSTI)

...''but we do not have quantum gravity.'' This phrase is often used when analysis of a physical problem enters the regime in which quantum gravity effects should be taken into account. In fact, there are several models of the gravitational field coupled to (scalar) fields for which the quantization procedure can be completed using loop quantum gravity techniques. The model we present in this paper consists of the gravitational field coupled to a scalar field. The result has similar structure to the loop quantum cosmology models, except that it involves all the local degrees of freedom of the gravitational field because no symmetry reduction has been performed at the classical level.

Domagala, Marcin; Kaminski, Wojciech [Instytut Fizyki Teoretycznej, Uniwersytet Warszawski, ul. Hoza 69, 00-681 Warszawa (Warsaw), Polska (Poland) (Poland); Giesel, Kristina [Excellence Cluster Universe, Technische Universitaet Muenchen, Boltzmannstrasse 2, 85748 Garching (Germany); Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803 (United States); Lewandowski, Jerzy [Instytut Fizyki Teoretycznej, Uniwersytet Warszawski, ul. Hoza 69, 00-681 Warszawa (Warsaw), Polska (Poland) (Poland); Institute for Gravitation and the Cosmos, Physics Department, Penn State, University Park, Pennsylvania 16802 (United States)

2010-11-15T23:59:59.000Z

32

Ground Gravity Survey At Maui Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

Ground Gravity Survey At Maui Area (DOE GTP) Exploration Activity Details Location Maui Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated...

33

Gravity settling  

DOE Patents (OSTI)

Solids are separated from a liquid in a gravity settler provided with inclined solid intercepting surfaces to intercept the solid settling path to coalesce the solids and increase the settling rate. The intercepting surfaces are inverted V-shaped plates, each formed from first and second downwardly inclined upwardly curved intersecting conical sections having their apices at the vessel wall.

Davis, Hyman R. (Glenridge, NJ); Long, R. H. (Morristown, NJ); Simone, A. A. (Dover, NJ)

1979-01-01T23:59:59.000Z

34

Understanding gravity  

E-Print Network (OSTI)

AdS/CFT correspondence provides a holographic duality between gravitational physics and gauge dynamics. What field theory configurations lend themselves to a good semi-classical description? Relevance: Making precise the nature of the holographic map Understanding the emergence of geometry. What are “legal ” singularities in gravity (cosmic censorship)? Insight into new solutions. Motivation Conformal fluids Bulk geometry Horizons & entropy Conclusion

Mukund Rangamani

2008-01-01T23:59:59.000Z

35

Airborne Inspection Technology: Market Survey  

Science Conference Proceedings (OSTI)

This report presents findings of an investigation into various airborne inspection technologies currently used within the electric utility industry.

2002-03-04T23:59:59.000Z

36

Is nonrelativistic gravity possible?  

SciTech Connect

We study nonrelativistic gravity using the Hamiltonian formalism. For the dynamics of general relativity (relativistic gravity) the formalism is well known and called the Arnowitt-Deser-Misner (ADM) formalism. We show that if the lapse function is constrained correctly, then nonrelativistic gravity is described by a consistent Hamiltonian system. Surprisingly, nonrelativistic gravity can have solutions identical to relativistic gravity ones. In particular, (anti-)de Sitter black holes of Einstein gravity and IR limit of Horava gravity are locally identical.

Kocharyan, A. A. [School of Mathematical Sciences, Monash University, Clayton 3800 (Australia)

2009-07-15T23:59:59.000Z

37

Intrusive gravity currents  

E-Print Network (OSTI)

The front speed of intrusive gravity currents. J. FluidP.F. Linden. Intrusive gravity currents. J. Fluid Mechanics,of mesoscale variability of gravity waves. Part II: Frontal,

Hang, Alice Thanh

2009-01-01T23:59:59.000Z

38

TORSION AND QUANTUM GRAVITY  

E-Print Network (OSTI)

more restrictive context of Einstein's theory of gravity.6782 TORSION AND QUANTUM GRAVITY Andrevr J, Him son Lawrencetorsion in conventional gravity cou~d in fact be dynamicaL A

Hanson, Andrew J.

2011-01-01T23:59:59.000Z

39

Airborne wireless communication systems, airborne communication methods, and communication methods  

SciTech Connect

An airborne wireless communication system includes circuitry configured to access information describing a configuration of a terrestrial wireless communication base station that has become disabled. The terrestrial base station is configured to implement wireless communication between wireless devices located within a geographical area and a network when the terrestrial base station is not disabled. The circuitry is further configured, based on the information, to configure the airborne station to have the configuration of the terrestrial base station. An airborne communication method includes answering a 911 call from a terrestrial cellular wireless phone using an airborne wireless communication system.

Deaton, Juan D. (Menan, ID); Schmitt, Michael J. (Idaho Falls, ID); Jones, Warren F. (Idaho Falls, ID)

2011-12-13T23:59:59.000Z

40

Newtonian gravity in loop quantum gravity  

E-Print Network (OSTI)

We apply a recent argument of Verlinde to loop quantum gravity, to conclude that Newton's law of gravity emerges in an appropriate limit and setting. This is possible because the relationship between area and entropy is realized in loop quantum gravity when boundaries are imposed on a quantum spacetime.

Smolin, Lee

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Real-Time Airborne Analysis of Aircraft Data Supporting Operational Hurricane Forecasting  

Science Conference Proceedings (OSTI)

The Hurricane Research Division has developed a technique for real-time airborne analysis of aircraft data from reconnaissance and research flights in tropical cyclones. The technique uses an onboard workstation that analyzes flight-level ...

Joseph S. Griffin; Robert W. Burpee; Frank D. Marks Jr.; James L. Franklin

1992-09-01T23:59:59.000Z

42

Derivation of Effective Aerodynamic Surface Roughness in Urban Areas from Airborne Lidar Terrain Data  

Science Conference Proceedings (OSTI)

An automated technique was developed that uses only airborne lidar terrain data to derive the necessary parameters for calculation of effective aerodynamic surface roughness in urban areas. The technique provides parameters for geometric models ...

Donald E. Holland; Judith A. Berglund; Joseph P. Spruce; Rodney D. McKellip

2008-10-01T23:59:59.000Z

43

High-gravity central stars  

E-Print Network (OSTI)

NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which is apparently exhibited at the stellar surface. We summarize recent results from imaging, spectroscopy, and spectropolarimetry.

Thomas Rauch

2006-07-11T23:59:59.000Z

44

Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski...  

Open Energy Info (EERE)

Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski, Et Al., 2004) Exploration Activity Details Location San Francisco Volcanic Field Area Exploration Technique...

45

Ground Gravity Survey At Coso Geothermal Area (1980) | Open Energy...  

Open Energy Info (EERE)

Activity Details Location Coso Geothermal Area Exploration Technique Ground Gravity Survey Activity Date 1980 Usefulness not indicated DOE-funding Unknown Notes The...

46

Ground Gravity Survey At Kilauea East Rift Area (Broyles, Et...  

Open Energy Info (EERE)

Activity Details Location Kilauea East Rift Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown References M. L....

47

Ground Gravity Survey At Raft River Geothermal Area (1978) |...  

Open Energy Info (EERE)

Activity Details Location Raft River Geothermal Area Exploration Technique Ground Gravity Survey Activity Date 1978 Usefulness not indicated DOE-funding Unknown Exploration...

48

Chiral gravity, log gravity, and extremal CFT  

Science Conference Proceedings (OSTI)

We show that the linearization of all exact solutions of classical chiral gravity around the AdS{sub 3} vacuum have positive energy. Nonchiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity--the theory with logarithmically relaxed boundary conditions--has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic conformal field theories (CFT). Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We formally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

Maloney, Alexander [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Song Wei [Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190 (China); Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States); Strominger, Andrew [Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States)

2010-03-15T23:59:59.000Z

49

Chiral Gravity, Log Gravity and Extremal CFT  

E-Print Network (OSTI)

We show that the linearization of all exact solutions of classical chiral gravity around the AdS3 vacuum have positive energy. Non-chiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity-- the theory with logarithmically relaxed boundary conditions --has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic CFT. Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We normally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

Alexander Maloney; Wei Song; Andrew Strominger

2009-03-26T23:59:59.000Z

50

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

Open Energy Info (EERE)

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

51

Modeling for Airborne Contamination  

SciTech Connect

The objective of Modeling for Airborne Contamination (referred to from now on as ''this report'') is to provide a documented methodology, along with supporting information, for estimating the release, transport, and assessment of dose to workers from airborne radioactive contaminants within the Monitored Geologic Repository (MGR) subsurface during the pre-closure period. Specifically, this report provides engineers and scientists with methodologies for estimating how concentrations of contaminants might be distributed in the air and on the drift surfaces if released from waste packages inside the repository. This report also provides dose conversion factors for inhalation, air submersion, and ground exposure pathways used to derive doses to potentially exposed subsurface workers. The scope of this report is limited to radiological contaminants (particulate, volatile and gaseous) resulting from waste package leaks (if any) and surface contamination and their transport processes. Neutron activation of air, dust in the air and the rock walls of the drift during the preclosure time is not considered within the scope of this report. Any neutrons causing such activation are not themselves considered to be ''contaminants'' released from the waste package. This report: (1) Documents mathematical models and model parameters for evaluating airborne contaminant transport within the MGR subsurface; and (2) Provides tables of dose conversion factors for inhalation, air submersion, and ground exposure pathways for important radionuclides. The dose conversion factors for air submersion and ground exposure pathways are further limited to drift diameters of 7.62 m and 5.5 m, corresponding to the main and emplacement drifts, respectively. If the final repository design significantly deviates from these drift dimensions, the results in this report may require revision. The dose conversion factors are further derived by using concrete of sufficient thickness to simulate the drift walls. The gamma-ray scattering properties of concrete are sufficiently similar to those of the host rock and proposed insert material; use of concrete will have no significant impact on the conclusions. The information in this report is presented primarily for use in performing pre-closure radiological safety evaluations of radiological contaminants, but it may also be used to develop strategies for contaminant leak detection and monitoring in the MGR. Included in this report are the methods for determining the source terms and release fractions, and mathematical models and model parameters for contaminant transport and distribution within the repository. Various particle behavior mechanisms that affect the transport of contaminant are included. These particle behavior mechanisms include diffusion, settling, resuspension, agglomeration and other deposition mechanisms.

F.R. Faillace; Y. Yuan

2000-08-31T23:59:59.000Z

52

Towards noncommutative gravity  

E-Print Network (OSTI)

In this short article accessible for non-experts I discuss possible ways of constructing a non-commutative gravity paying special attention to possibilities of realizing the full diffeomorphism symmetry and to relations with 2D gravities.

D. V. Vassilevich

2009-02-04T23:59:59.000Z

53

Heigth and Gravity  

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

Heigth and Gravity Name: Evan Location: NA Country: NA Date: NA Question: Does gravity effect a person's height? How does it? Would people with back problems benefit from time...

54

Airborne Wind Turbine  

Science Conference Proceedings (OSTI)

Broad Funding Opportunity Announcement Project: Makani Power is developing an Airborne Wind Turbine (AWT) that eliminates 90% of the mass of a conventional wind turbine and accesses a stronger, more consistent wind at altitudes of near 1,000 feet. At these altitudes, 85% of the country can offer viable wind resources compared to only 15% accessible with current technology. Additionally, the Makani Power wing can be economically deployed in deep offshore waters, opening up a resource which is 4 times greater than the entire U.S. electrical generation capacity. Makani Power has demonstrated the core technology, including autonomous launch, land, and power generation with an 8 meter wingspan, 20 kW prototype. At commercial scale, Makani Power aims to develop a 600 kW, 28 meter wingspan product capable of delivering energy at an unsubsidized cost competitive with coal, the current benchmark for low-cost power.

None

2010-09-01T23:59:59.000Z

55

Motion in Quantum Gravity  

E-Print Network (OSTI)

We tackle the question of motion in Quantum Gravity: what does motion mean at the Planck scale? Although we are still far from a complete answer we consider here a toy model in which the problem can be formulated and resolved precisely. The setting of the toy model is three dimensional Euclidean gravity. Before studying the model in detail, we argue that Loop Quantum Gravity may provide a very useful approach when discussing the question of motion in Quantum Gravity.

Karim Noui

2010-03-31T23:59:59.000Z

56

Stephen Hawking Quantum Gravity  

E-Print Network (OSTI)

Stephen Hawking and Quantum Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 4 Nov 2000 #12; Stephen Hawking and Quantum Gravity Abstract: Through research, Stephen Hawking has captured a place in the popular imagina- tion. Quantum gravity in its various

Visser, Matt

57

Quantum Physics Einstein's Gravity  

E-Print Network (OSTI)

Quantum Physics confronts Einstein's Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 13 October 2001 #12; Quantum Physics confronts Einstein's Gravity and with Einstein's theory of gravity (the general relativity) is still the single biggest theoretical problem

Visser, Matt

58

Ultraviolet Complete Quantum Gravity  

E-Print Network (OSTI)

An ultraviolet complete (UV) quantum gravity theory is formulated in which vertex functions in Feynman graphs are entire functions and the propagating gravitons are described by local, causal propagators. A scalar-tensor action describes classical gravity theory. The cosmological constant problem is investigated in the context of the UV complete quantum gravity.

Moffat, J W

2010-01-01T23:59:59.000Z

59

Analysis and Processing of Airborne LIDAR Data  

E-Print Network (OSTI)

Airborne LIDAR systems have been in use for many years to measure points on the earth's surface. They can rapidly produce accurate digital surface models and offer significantly lower costs in field operations and post-processing compared to traditional survey methods. This makes the LIDAR technology an attractive alternative for a variety of mapping applications. From scattered 3-D point clouds to useful representations for end-users requires further research and development of post-processing algorithms. Up to now, the post-processing of LIDAR data is still in an early phase of development because no single technique currently is considered optimum or satisfactory for all conditions and requirements.

Yong Hu

2001-01-01T23:59:59.000Z

60

The Universe Adventure - Gravity  

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

Gravity: The Main Attraction Gravity: The Main Attraction Gravity Acts on All Matter Gravity's effect is apparent even at the largest scales: just as gravity keeps the Earth orbiting the sun, it holds these two irregular galaxies M32 and M110 in orbit around the larger Andromeda galaxy. In the late 1600s, the English mathematician Sir Isaac Newton gave the first scientific description of gravitation. Gravity is an attractive force existing between any two objects that have mass, causing them to accelerate towards each other. It is the weakest of the four fundamental forces but can act over great distances and is responsible for the formation of planets, stars, galaxies, and even larger scale structures such as groups and superclusters. Gravity is also the force that governs the motion of

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Quantization of Emergent Gravity  

E-Print Network (OSTI)

Emergent gravity is based on a novel form of the equivalence principle known as the Darboux theorem or the Moser lemma in symplectic geometry stating that the electromagnetic force can always be eliminated by a local coordinate transformation as far as spacetime admits a symplectic structure, in other words, a microscopic spacetime becomes noncommutative (NC). If gravity emerges from U(1) gauge theory on NC spacetime, this picture of emergent gravity suggests a completely new quantization scheme where quantum gravity is defined by quantizing spacetime itself, leading to a dynamical NC spacetime. Therefore the quantization of emergent gravity is radically different from the conventional approach trying to quantize a phase space of metric fields. This approach for quantum gravity allows a background independent formulation where spacetime as well as matter fields is equally emergent from a universal vacuum of quantum gravity.

Hyun Seok Yang

2013-12-02T23:59:59.000Z

62

The Structure of Thermals in Cumulus from Airborne Dual-Doppler Radar Observations  

Science Conference Proceedings (OSTI)

A newly developed technique for airborne dual-Doppler observations with the Wyoming Cloud Radar is used to characterize the velocity fields in vertical planes across cumulus turrets. The clouds sampled were continental in nature, with high bases (...

Rick Damiani; Gabor Vali; Samuel Haimov

2006-05-01T23:59:59.000Z

63

Use of the Inertial Dissipation Method for Calculating Turbulent Fluxes from Low-Level Airborne Measurements  

Science Conference Proceedings (OSTI)

Airborne measurements are currently used for computing turbulence fluxes of heat and momentum. The method generally used is the eddy correlation technique, which requires sophisticated equipments to calculate the absolute velocities of the air. ...

Pierre Durand; Leonardo De Sa; Aimé Druilhet; Frédérique Said

1991-02-01T23:59:59.000Z

64

An Objective Method for Deriving Atmospheric Structure from Airborne Lidar Observations  

Science Conference Proceedings (OSTI)

Wavelet analysis is applied to airborne infrared lidar data to obtain an objective determination of boundaries in aerosol backscatter that are associated with boundary layer structure. This technique allows high-resolution spatial variability of ...

K. J. Davis; N. Gamage; C. R. Hagelberg; C. Kiemle; D. H. Lenschow; P. P. Sullivan

2000-11-01T23:59:59.000Z

65

Ground Gravity Survey At Coso Geothermal Area (1990) | Open Energy  

Open Energy Info (EERE)

Coso Geothermal Area (1990) Coso Geothermal Area (1990) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Coso Geothermal Area (1990) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Ground Gravity Survey Activity Date 1990 Usefulness not indicated DOE-funding Unknown Exploration Basis To identify features related to the heat source and to seek possible evidence for an underlying magma chamber Notes 2D and 3D gravity modeling was done using gridded Bouguer gravity data covering a 45 by 45 km region over the Coso geothermal area. Isostatic and terrain corrected Bouguer gravity data for about 1300 gravity stations were obtained from the US Geological Survey. After the data were checked, the gravity values were gridded at 1 km centers for the area of interest

66

A Dual-Pulse Repetition Frequency Scheme for Mitigating Velocity Ambiguities of the NOAA P-3 Airborne Doppler Radar  

Science Conference Proceedings (OSTI)

To mitigate some of the deleterious effects of the relatively small unambiguous Doppler velocity range (Nyquist interval) of airborne X-band Doppler radars, a technique has been developed to extend this interval. This technique, termed the batch-...

David P. Jorgensen; Tom R. Shepherd; Alan S. Goldstein

2000-05-01T23:59:59.000Z

67

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

Open Energy Info (EERE)

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

68

Airborne Doppler Radar Data Analysis Workshop  

Science Conference Proceedings (OSTI)

The Airborne Doppler Radar Data Analysis Workshop, sponsored by the Atmospheric Technology Division (ATD) of the National Center for Atmospheric Research (NCAR), was the first to focus on analyzing airborne Doppler radar data. The workshop (held ...

Wen-Chau Lee; Frank D. Marks; Craig Walther

2003-08-01T23:59:59.000Z

69

Lectures on loop gravity  

E-Print Network (OSTI)

This is the first version of the introductory lectures on loop quantum gravity that I will give at the quantum gravity school in Zakopane. The theory is presented in self-contained form, without emphasis on its derivation from classical general relativity. Dynamics is given in the covariant form. The approximations needed to compute physical quantities are discussed. Some applications are described, including the recent derivation of de Sitter cosmology from full quantum gravity.

Rovelli, Carlo

2011-01-01T23:59:59.000Z

70

Dark gravity and cosmology  

E-Print Network (OSTI)

The previous version of this article was a first attempt to confront the Dark Gravity theory to cosmological data. However, more recent developments lead to the conclusion that the cosmological principle is probably not valid in Dark Gravity so that this kind of analysis is at best very premature. A more recent and living review of the Dark Gravity theory can be found in gr-qc/0610079

F. Henry-Couannier; A. Tilquin; C. Tao; A. Ealet

2005-09-05T23:59:59.000Z

71

Is Gravity an Interaction?  

E-Print Network (OSTI)

We consider a possibility that gravity is not an interaction but a manifestation of a symmetry based on a Galois field.

Felix M. Lev

2009-05-06T23:59:59.000Z

72

Gold Standard Gravity  

E-Print Network (OSTI)

This paper provides striking confirmation of the restrictions of the structural gravity model of trade. Structural forces predicted by theory explain 95 % of the variation of the fixed effects used to control for them in the recent gravity literature, fixed effects that in principle could reflect other forces. This validation opens avenues to inferring unobserved sectoral activity and multilateral resistance variables by equating fixed effects with structural gravity counterparts. Our findings also provide important validation of a host of general equilibrium comparative static exercises based on the structural gravity model.

James E. Anderson; Yoto V. Yotov; Dave Donaldson; Keith Head; Michael Waugh; We Arthur Lewbel

2012-01-01T23:59:59.000Z

73

Airborne remote sensing in the frozen north  

E-Print Network (OSTI)

20 Airborne remote sensing in the frozen north High level shot from 10,000 feet shows, Chief Pilot and Operations Manager for NERC's Airborne Remote Sensing Facility reports on a recent trip expert ­ the Airborne Remote Sensing Facility flew to the Norwegian archipelago of Svalbard on August 3

Brierley, Andrew

74

Quantum gravity on the lattice  

E-Print Network (OSTI)

the Conference Quantum Gravity: Challenges and Perspectives.divergences in quantum gravity. In: Hawking, S.W. , Israel,f ) V n?1 ( f ) = Quantum gravity on the lattice Similarly,

Hamber, Herbert W.

2009-01-01T23:59:59.000Z

75

Particle Dynamics And Emergent Gravity  

E-Print Network (OSTI)

The emergent gravity proposal is examined within the framework of noncommutative QED/gravity correspondence from particle dynamics point of view.

Amir H. Fatollahi

2008-05-08T23:59:59.000Z

76

Gauge/Gravity Duality (Gauge Gravity Duality)  

SciTech Connect

Gauge theories, which describe the particle interactions, are well understood, while quantum gravity leads to many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand, this provides our most precise description of quantum gravity, resolves some long-standing paradoxes, and points to new principles. On the other, it gives a new perspective on strong interactions, with surprising connections to other areas of physics. I describe these ideas, and discuss current and future directions.

Polchinski, Joseph (Kavli Institute for Theoretical Physics)

2010-02-24T23:59:59.000Z

77

Probability around the Quantum Gravity. Part 1: Planar Pure Gravity  

E-Print Network (OSTI)

Probability around the Quantum Gravity. Part 1: Planar Pure Gravity V.A.Malyshev \\Lambda September 17, 1998 Abstract In this paper we study stochastic dynamics which leaves quantum gravity equilibrium science and biology. At the same time the paper can serve an intro­ duction to quantum gravity

78

Gravity in Gauge Mediation  

E-Print Network (OSTI)

We investigate O'Raifeartaigh-type models for F-term supersymmetry breaking in gauge mediation scenarios in the presence of gravity. It is pointed out that the vacuum structure of those models is such that in metastable vacua gravity mediation contribution to scalar masses is always suppressed to the level below 1 percent, almost sufficient for avoiding FCNC problem. Close to that limit, gravitino mass can be in the range 10-100 GeV, opening several interesting possibilities for gauge mediation models, including Giudice-Masiero mechanism for mu and Bmu generation. Gravity sector can include stabilized moduli.

Zygmunt Lalak; Stefan Pokorski; Krzysztof Turzynski

2008-08-04T23:59:59.000Z

79

Quantum Gravity An introductory survey  

E-Print Network (OSTI)

Quantum Gravity An introductory survey Hermann Nicolai Max-Planck-Institut f¨ur Gravitationsphysik (Albert­Einstein­Institut, Potsdam) . ­ p.1/25 #12;Why Quantum Gravity? . ­ p.2/25 #12;Why Quantum Gravity theories: . ­ p.2/25 #12;Why Quantum Gravity? General Relativity and Quantum Theory: not only very

Rossak, Wilhelm R.

80

Toroidal solutions in Horava Gravity  

E-Print Network (OSTI)

Recently a new four-dimensional non relativistic renormalizable theory of gravity was proposed by Horava. This gravity reduces to Einstein gravity at large distances. In this paper by using the new action for gravity we present different toroidal solutions to the equations of motion. Our solutions describe the near horizon geometry with slow rotating parameter.

Ahmad Ghodsi

2009-05-06T23:59:59.000Z

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


81

Equivalence between therm and gravity  

E-Print Network (OSTI)

We introduce the notion of thermal entropy density, and first demonstrated that there exists an equivalence between therm and gravity without depending on the definition of temperature or horizon. This equivalence indicates that gravity possesses thermal features, or, therm possesses effects of gravity. This may shed light on the nature of gravity.

Yang, Rong-Jia

2011-01-01T23:59:59.000Z

82

Gravity and the quantum potential  

E-Print Network (OSTI)

We review some material connecting gravity and the quantum potential and provide a few new observations.

Robert Carroll

2004-06-02T23:59:59.000Z

83

Free Gravity Waves and Balanced Dynamics  

Science Conference Proceedings (OSTI)

It is shown how a renormalization technique, which is a variant of classical Krylov–Bogolyubov–Mitropol'skii averaging, can be used to obtain slow evolution equations for the vortical and inertia–gravity wave components of the dynamics in a ...

D. Wirosoetisno; T. G. Shepherd; R. M. Temam

2002-12-01T23:59:59.000Z

84

Gravity Waves from Thunderstorms  

Science Conference Proceedings (OSTI)

Gravity waves generated by severe thunderstorms in the eastern Ohio-Pennsylvania area were recorded by an array of microbarovariographs at Palisades, New York and by standard microbarographs across northeastern United States. The waves were ...

Nambath K. Balachandran

1980-06-01T23:59:59.000Z

85

Why gravity is fundamental  

E-Print Network (OSTI)

It is argued that the existence of a minimum size of spacetime may imply the fundamental existence of gravity as a geometric property of spacetime described by general relativity.

Shan Gao

2010-01-18T23:59:59.000Z

86

Causal Newton Gravity Law  

E-Print Network (OSTI)

The equations of the relativistic causal Newton gravity law for the planets of the solar system are studied in the approximation when the Sun rests at the coordinates origin and the planets do not iteract between each other.

Yury M. Zinoviev

2012-01-17T23:59:59.000Z

87

Exercise in artificial gravity  

E-Print Network (OSTI)

Artificial gravity provided by short radius centrifugation is considered a promising countermeasure to the deleterious physiological effects of microgravity during long-duration space flight. We investigated the feasibility ...

Edmonds, Jessica Leigh

2005-01-01T23:59:59.000Z

88

Dog Center of Gravity  

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

Dog Center of Gravity Name: Dania Status: Student Grade: 9-12 Location: AZ Country: USA Date: NA Question: Currently in physics we are working with projectile motion. I am...

89

Why gravity is fundamental  

E-Print Network (OSTI)

It is argued that the existence of a minimum size of spacetime may imply the fundamental existence of gravity as a geometric property of spacetime described by general relativity.

Gao, Sheldon

2010-01-01T23:59:59.000Z

90

Tracking Gravity Waves in Baroclinic Jet-Front Systems  

Science Conference Proceedings (OSTI)

Using a two-dimensional Fourier decomposition and a four-dimensional ray-tracing technique, the propagating characteristics and source mechanisms of mesoscale gravity waves simulated in idealized baroclinic jet-front systems are investigated. The ...

Yonghui Lin; Fuqing Zhang

2008-07-01T23:59:59.000Z

91

An Upper Gravity-Wave Absorbing Layer for NWP Applications  

Science Conference Proceedings (OSTI)

Although the use of a damping layer near the top of a computational model domain has proven effective in absorbing upward-propagating gravity-wave energy in idealized simulations, this technique has been less successful in real atmospheric ...

J. B. Klemp; J. Dudhia; A. D. Hassiotis

2008-10-01T23:59:59.000Z

92

Inference of Marine Atmospheric Boundary Layer Moisture and Temperature Structure Using Airborne Lidar and Infrared Radiometer Data  

Science Conference Proceedings (OSTI)

A new technique for retrieving near-surface moisture and profiles of mixing ratio and potential temperature through the depth of the marine atmospheric boundary layer (MABL) using airborne lidar and multichannel infrared radiometer data is ...

Stephen P. Palm; Denise Hagan; Geary Schwemmer; S. H. Melfi

1998-03-01T23:59:59.000Z

93

Ground Gravity Survey At San Emidio Desert Area (DOE GTP) | Open...  

Open Energy Info (EERE)

Activity Details Location San Emidio Desert Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes (prior to...

94

Ground Gravity Survey At New River Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

GTP) Exploration Activity Details Location New River Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown References (1...

95

Gravity-driven intrusions in stratified fluids  

E-Print Network (OSTI)

5.5.1 Five interleaving interfacial gravity currents 5.5.2Ten interleaving interfacial gravity currents . 5.6partial- depth intrusive gravity currents,” Atmosphere -

Maurer, Benjamin Dudley

2011-01-01T23:59:59.000Z

96

Airborne observations of methane emissions from rice cultivation...  

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

Airborne observations of methane emissions from rice cultivation in the Sacramento Valley of California Title Airborne observations of methane emissions from rice cultivation in...

97

Exploring Gravity and Gravitational Wave Dynamics Part II: Gravity Models  

Science Conference Proceedings (OSTI)

The need for a new gravity model may explain anomalous behavior exhibited by several recent experiments described in Part I. Although Newtonian gravity is adequate for predicting the motion of celestial bodies

P. A. Murad

2007-01-01T23:59:59.000Z

98

On the no-gravity limit of gravity  

E-Print Network (OSTI)

We argue that Relative Locality may arise in the no gravity $G\\rightarrow0$ limit of gravity. In this limit gravity becomes a topological field theory of the BF type that, after coupling to particles, may effectively deform its dynamics. We briefly discuss another no gravity limit with a self dual ground state as well as the topological ultra strong $G\\rightarrow\\infty$ one.

Kowalski-Glikman, J

2012-01-01T23:59:59.000Z

99

Glossary API Gravity: An  

Gasoline and Diesel Fuel Update (EIA)

5 60 60 131 5 . . The higher the API gravity, the lighter the compound. Light crudes generally exceed 38 degrees API and heavy crudes are commonly labeled as all crudes with an API gravity of 22 degrees or below. Intermediate crudes fall in the range of 22 degrees to 38 degrees API gravity. ASTM: American Society for Testing and Materials. Aviation Gasoline (Finished): A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in aviation reciprocating engines. Fuel specifi- cations are provided in ASTM Specification D 910 and Military Specification MIL-G-5572. Note: Data on blending components are not counted in data on fin- ished aviation gasoline. Barrel: A volumetric unit of measure for crude oil and petroleum products equivalent to 42 U.S. gallons. Bulk Sales: Wholesale sales of gasoline in individual

100

Glossary API Gravity: An  

Gasoline and Diesel Fuel Update (EIA)

60 60 1315 . . The higher the API gravity, the lighter the compound. Light crudes generally exceed 38 degrees API and heavy crudes are commonly labeled as all crudes with an API gravity of 22 degrees or below. Intermediate crudes fall in the range of 22 degrees to 38 degrees API gravity. ASTM: American Society for Testing and Materials. Aviation Gasoline (Finished): A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in aviation reciprocating engines. Fuel specifi- cations are provided in ASTM Specification D 910 and Military Specification MIL-G-5572. Note: Data on blending components are not counted in data on fin- ished aviation gasoline. Barrel: A volumetric unit of measure for crude oil and petroleum products equivalent to 42 U.S. gallons. Bulk Sales: Wholesale sales of gasoline in individual

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Macroscopic quantization of gravity  

E-Print Network (OSTI)

The moon is receding from earth at an average rate of 3.8 cm/yr [6][7][9][12].This anomaly cannot be attributed to the well-known tidal exchange of angular momentum between earth and moon [8]. A secular change in the astronomical unit AU is definitely a concern, it is reportedly increasing by about 15 cm/yr [9][10], in this letter; the concept of macroscopic quantization of gravity is introduced to account for these anomalies on theoretical basis. Interestingly, it was found useful in measuring the speed of gravity! What is more interesting is the fact that this concept is based on solid well known classical physics with no modifications to any standard model. It was found that the speed of gravity cg is in the range 10^4 c < cg < 10^5 c.

M. Y. Amin

2009-12-12T23:59:59.000Z

102

Euler Chern Simons Gravity from Lovelock Born Infeld Gravity  

E-Print Network (OSTI)

In the context of a gauge theoretical formulation, higher dimensional gravity invariant under the AdS group is dimensionally reduced to Euler-Chern-Simons gravity. The dimensional reduction procedure of Grignani-Nardelli [Phys. Lett. B 300, 38 (1993)] is generalized so as to permit reducing D-dimensional Lanczos Lovelock gravity to d=D-1 dimensions.

Fernando Izaurieta; Eduardo Rodriguez; Patricio Salgado

2004-02-25T23:59:59.000Z

103

Gravity wraps Higgs boson  

E-Print Network (OSTI)

It is shown that, by rescaling the matter fields and metric tensor with appropriate powers of the Higgs field, the Higgs boson can be wholly transferred from material sector to the gravity sector in which it possesses only gravitational interactions and escapes detection in collider experiments. The Higgs boson gets buried in a scalar-tensor theory of gravity wherein it might be of relevance for Dark Energy. It is absent from the electroweak spectrum yet leptons, quarks and vector bosons possess their already known properties. The Higgs boson can contact with the matter sector via only the higher-dimensional operators suppressed by a cutoff scale.

Demir, Durmus A

2011-01-01T23:59:59.000Z

104

Sodium Nightglow and Gravity Waves  

Science Conference Proceedings (OSTI)

Oscillations in intensity of NaD nightglow attributed to mesospheric gravity waves have bean studied. Fractional atmospheric density perturbations have been obtained by means of the linear gravity waves theory of Hines. Values of other parameters ...

A. Molina

1983-10-01T23:59:59.000Z

105

Quantum gravity on the lattice  

E-Print Network (OSTI)

C. : Fields on a random lattice. In: Progress in Gauge Field= Quantum gravity on the lattice Similarly, one can considerQuantum gravity on the lattice Herbert W. Hamber Received:

Hamber, Herbert W.

2009-01-01T23:59:59.000Z

106

Introduction to Loop Quantum Gravity  

E-Print Network (OSTI)

The questions I have been asked during the 5th International School on Field Theory and Gravitation, have compelled me to give an account of the premises that I consider important for a beginner's approach to Loop Quantum Gravity. After a description of some general arguments and an introduction to the canonical theory of gravity, I review the background independent approach to quantum gravity, giving only a brief survey of Loop Quantum Gravity.

Mercuri, Simone

2010-01-01T23:59:59.000Z

107

Gravity's weight on worldline fuzziness  

E-Print Network (OSTI)

We investigate a connection between recent results in 3D quantum gravity, providing an effective noncommutative-spacetime description, and some earlier heuristic descriptions of a quantum-gravity contribution to the fuzziness of the worldlines of particles. We show that 3D-gravity-inspired spacetime noncommutativity reflects some of the features suggested by previous heuristic arguments. Most notably, gravity-induced worldline fuzziness, while irrelevantly small on terrestrial scales, could be observably large for propagation of particles over cosmological distances.

Amelino-Camelia, Giovanni; Rosati, Giacomo

2012-01-01T23:59:59.000Z

108

Introduction to Loop Quantum Gravity  

E-Print Network (OSTI)

The questions I have been asked during the 5th International School on Field Theory and Gravitation, have compelled me to give an account of the premises that I consider important for a beginner's approach to Loop Quantum Gravity. After a description of some general arguments and an introduction to the canonical theory of gravity, I review the background independent approach to quantum gravity, giving only a brief survey of Loop Quantum Gravity.

Simone Mercuri

2010-01-08T23:59:59.000Z

109

Massive gravity on a brane  

E-Print Network (OSTI)

Dam, Veltman and Zakharov [13], implies that the tensor structure of the gravitational interaction deviates from that of Einstein gravity.

Chacko, Z.; Graesser, M.L.; Grojean, C.; Pilo, L.

2003-01-01T23:59:59.000Z

110

New probe of modified gravity  

E-Print Network (OSTI)

We suggest a new efficient way to constrain a certain class of large scale modifications of gravity. We show that the scale-free relation between density and size of Dark Matter halos, predicted within the LambdaCDM model with Newtonian gravity, gets modified in a wide class of theories of modified gravity.

Boyarsky, Alexey

2010-01-01T23:59:59.000Z

111

D-Dimensional Log Gravity  

E-Print Network (OSTI)

We study Einstein gravity in dimensions $D\\geq 4$ modified by curvature squared at critical point where the theory contains only massless gravitons. We show that at the critical point a new mode appears leading to a logarithmic gravity in the theory. The corresponding logarithmic solution may provide a gravity description of logarithmic CFT in higher dimensions.

Alishahiha, Mohsen

2011-01-01T23:59:59.000Z

112

5, 1102911054, 2005 Convective gravity  

E-Print Network (OSTI)

ACPD 5, 11029­11054, 2005 Convective gravity waves at mid-latitudes Y. G. Choi et al. Title Page Discussions Wind-profiler observations of gravity waves produced by convection at mid-latitudes Y. G. Choi1­11054, 2005 Convective gravity waves at mid-latitudes Y. G. Choi et al. Title Page Abstract Introduction

Paris-Sud XI, Université de

113

CFT, Integrable Models Liouville Gravity  

E-Print Network (OSTI)

CFT, Integrable Models And Liouville Gravity Chernogolovka 2009 Sunday June 28, 2009. Conference as one of components of their L, A pairs. #12;CFT, Integrable Models And Liouville Gravity Chernogolovka Gravity Chernogolovka, 2009 Tuesday June 30, 2009. CONFERENCE HALL 09:30­10:10 Herman Boos (Wuppertal

Fominov, Yakov

114

From Classical To Quantum Gravity: Introduction to Loop Quantum Gravity  

E-Print Network (OSTI)

We present an introduction to the canonical quantization of gravity performed in loop quantum gravity, based on lectures held at the 3rd quantum geometry and quantum gravity school in Zakopane in 2011. A special feature of this introduction is the inclusion of new proposals for coupling matter to gravity that can be used to deparametrize the theory, thus making its dynamics more tractable. The classical and quantum aspects of these new proposals are explained alongside the standard quantization of vacuum general relativity in loop quantum gravity.

Giesel, Kristina

2012-01-01T23:59:59.000Z

115

Even-dimensional topological gravity from Chern-Simons gravity  

E-Print Network (OSTI)

It is shown that the topological action for gravity in 2n-dimensions can be obtained from the 2n+1-dimensional Chern-Simons gravity genuinely invariant under the Poincare group. The 2n-dimensional topological gravity is described by the dynamics of the boundary of a 2n+1-dimensional Chern-Simons gravity theory with suitable boundary conditions. The field $\\phi^{a}$, which is necessary to construct this type of topological gravity in even dimensions, is identified with the coset field associated with the non-linear realizations of the Poincare group ISO(d-1,1).

Nelson Merino; Alfredo Perez; Patricio Salgado

2009-10-08T23:59:59.000Z

116

Bigravity and Massive Gravity  

Science Conference Proceedings (OSTI)

We discuss some issues concerning the global structure of spherically symmetric solutions of bigravity. We propose maximal extensions of manifolds where two causal structure coexist. Besides we make some comments about the perturbations of these solutions and their relation to massive gravity and the cosmological constant problem.

D. Blas

2006-01-01T23:59:59.000Z

117

Isometrodynamics and Gravity  

E-Print Network (OSTI)

Isometrodynamics (ID), the gauge theory of the group of volume-preserving diffeomorphisms of an "inner" D-dimensional flat space, is tentatively interpreted as a fundamental theory of gravity. Dimensional analysis shows that the Planck length l_P - and through it \\hbar and \\Gamma - enters the gauge field action linking ID and gravity in a natural way. Noting that the ID gauge field couples solely through derivatives acting on "inner" space variables all ID fields are Taylor-expanded in "inner" space. Integrating out the "inner" space variables yields an effective field theory for the coefficient fields with l_P^2 emerging as the expansion parameter. For \\hbar goint to zero only the leading order field does not vanish. This classical field couples to the matter Noether currents and charges related to the translation invariance in "inner" space. A model coupling this leading order field to a matter point source is established and solved. Interpreting the matter Noether charge in terms of gravitational mass Newton's inverse square law is finally derived for a static gauge field source and a slowly moving test particle. Gravity emerges as potentially related to field variations over "inner" space and might microscopically be described by the ID gauge field or equivalently by an infinite string of coefficient fields only the leading term of which is related to the macroscopical effects of gravity.

Christian Wiesendanger

2009-06-23T23:59:59.000Z

118

Quantum Gravity and Turbulence  

E-Print Network (OSTI)

We apply recent advances in quantum gravity to the problem of turbulence. Adopting the AdS/CFT approach we propose a string theory of turbulence that explains the Kolmogorov scaling in 3+1 dimensions and the Kraichnan and Kolmogorov scalings in 2+1 dimensions. In the gravitational context, turbulence is intimately related to the properties of spacetime, or quantum, foam.

Vishnu Jejjala; Djordje Minic; Y. Jack Ng; Chia-Hsiung Tze

2010-05-18T23:59:59.000Z

119

The gravity of light  

E-Print Network (OSTI)

A solution of the old problem raised by Tolman, Ehrenfest, Podolsky and Wheeler, concerning the lack of attraction of two light pencils "moving parallel", is proposed, considering that the light can be source of nonlinear gravitational waves corresponding (in the would be quantum theory of gravity) to spin-1 massless particles.

G. Sparano; G. Vilasi; S. Vilasi

2010-09-12T23:59:59.000Z

120

Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood & Mabey,  

Open Energy Info (EERE)

Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood & Mabey, Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood & Mabey, 1978) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood & Mabey, 1978) Exploration Activity Details Location Baltazor Hot Springs Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes The gravity map of the Baltazor KGRA (Fig. 2) shows a gravity low within the valley area that presumably is related to low-density Cenozoic sediments. The steep gravity gradient along the east side of the valley suggests a north-trending normal fault. The thickness of low-density fill is estimated to be about 300 m in the southwestern part of the KGRA and

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Preparation of residual gravity maps for the southern Cascade Mountains, Washington using Fourier analysis  

DOE Green Energy (OSTI)

A continuation of gravity work in the Cascade Mountains of Washington is presented. Baseline gravity data were collected for use in geothermal resource evaluation. The purpose of this report is to describe a Fourier analysis method for separating residual and regional gravity anomalies from a complete Bouguer gravity anomaly field. The technique has been applied to gravity data from the Southern Cascade Mountains, Washington. Residual gravity anomaly maps at a scale of 1:250,000 are presented for various regional wavelength filters, and a power spectrum of the frequency components in the South Cascade gravity data is displayed. No attempt is made to interpret the results of this study in terms of geologic structures.

Dishberger, D.M.

1983-04-01T23:59:59.000Z

122

SAFARI 2000 MODIS Airborne Simulator Data  

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

Airborne Simulator Data Airborne Simulator Data The ORNL DAAC announces the release of a new SAFARI 2000 data set. The data set "SAFARI 2000 MODIS Airborne Simulator Data, Southern Africa, Dry Season 2000" contains MODIS Airborne Simulator (MAS) multispectral data collected during the SAFARI 2000 project. Twenty flights with the MAS instrument were undertaken over Southern Africa by the NASA ER-2 aircraft during August and September 2000. The MAS spectrometer collects 50 multispectral bands at 16-bit resolution with a ground resolution of 50 meters from 20,000 meters altitude and a cross track scan width of 85.92 degrees. This data set is organized by flight, and each flight consists of several straight-line segments called tracks. There is a MAS multispectral data file for each track. The data are available in Hierarchical Data Format

123

Chemistry of airborne particles from metallurgical processing  

E-Print Network (OSTI)

Airborne particles fall into one of three size ranges. The nucleation range consists of nanoparticles created from vapor atom collisions. The decisive parameter for particle size and composition is the supercooling of the ...

Jenkins, Neil Travis, 1973-

2003-01-01T23:59:59.000Z

124

An Airborne APT Weather Satellite Imaging System  

Science Conference Proceedings (OSTI)

This paper describes the development of a novel airborne system that receives a real-time imagery broadcast in the Automatic Picture Transmission (APT) format from polar-orbiting weather satellites. The availability of such real-time imagery ...

James E. Jordan; David L. Marcotte; G. W. K. Moore

1998-02-01T23:59:59.000Z

125

Principles for Sampling Airborne Radioactivity from Stacks  

SciTech Connect

This book chapter describes the special processes involved in sampling the airborne effluents from nuclear faciities. The title of the book is Radioactive Air Sampling Methods. The abstract for this chapter was cleared as PNNL-SA-45941.

Glissmeyer, John A.

2010-10-18T23:59:59.000Z

126

Mapping of Airborne Doppler Radar Data  

Science Conference Proceedings (OSTI)

Two sets of equations are derived to 1) map airborne Doppler radar data from an aircraft-relative coordinate system to an earth-relative coordinate system, and 2) remove the platform motion from the observed Doppler velocities. These equations ...

Wen-Chau Lee; Peter Dodge; Frank D. Marks Jr.; Peter H. Hildebrand

1994-04-01T23:59:59.000Z

127

Performance of Some Airborne Thermometers in Clouds  

Science Conference Proceedings (OSTI)

The ability of airborne instruments to measure temperature in cloud is studied using theoretical analyses and experimental data. Theoretical predictions of the effects of sensor wetting are reviewed and modified, and are then compared to ...

R. Paul Lawson; William A. Cooper

1990-06-01T23:59:59.000Z

128

Waterspout Velocity Measurements by Airborne Doppler Lidar  

Science Conference Proceedings (OSTI)

A Doppler lidar measures the line-of-sight velocity of cloud droplets in a waterspout much as a meteorological Doppler radar measures the velocity of larger hydrometeors. We discuss details of the application of an airborne Doppler lidar to ...

R. L. Schwiesow; R. E. Cupp; P. C. Sinclair; R. F. Abbey Jr.

1981-04-01T23:59:59.000Z

129

Targeted Observations with an Airborne Wind Lidar  

Science Conference Proceedings (OSTI)

This study investigates the possibilities and limitations of airborne Doppler lidar for adaptive observations over the Atlantic Ocean. For the first time, a scanning 2-?m Doppler lidar was applied for targeted measurements during the Atlantic “...

M. Weissmann; R. Busen; A. Dörnbrack; S. Rahm; O. Reitebuch

2005-11-01T23:59:59.000Z

130

ABLE: Development of an Airborne Lidar  

Science Conference Proceedings (OSTI)

The acronym ABLE (Airborne Lidar Experiment) identifies a project to develop and fly an optical radar on a stratospheric platform for studies related to atmospheric radiation and composition. The prototype, ABLE 1, has been successfully flown on ...

Giorgio Fiocco; Paolo G. Calisse; Marco Cacciani; Stefano Casadio; Giandomenico Pace; Daniele Fua

1999-10-01T23:59:59.000Z

131

The Seasonal Cycle of Gravity Wave Drag in the Middle Atmosphere  

Science Conference Proceedings (OSTI)

Using a variational technique, middle atmosphere gravity wave drag (GWD) is estimated from Met Office middle atmosphere analyses for the year 2002. The technique employs an adjoint model of a middle atmosphere dynamical model to minimize a cost ...

Manuel Pulido; John Thuburn

2008-09-01T23:59:59.000Z

132

Chemical detection using the airborne thermal infrared imaging spectrometer (TIRIS)  

SciTech Connect

A methodology is described for an airborne, downlooking, longwave infrared imaging spectrometer based technique for the detection and tracking of plumes of toxic gases. Plumes can be observed in emission or absorption, depending on the thermal contrast between the vapor and the background terrain. While the sensor is currently undergoing laboratory calibration and characterization, a radiative exchange phenomenology model has been developed to predict sensor response and to facilitate the sensor design. An inverse problem model has also been developed to obtain plume parameters based on sensor measurements. These models, the sensors, and ongoing activities are described.

Gat, N.; Subramanian, S.; Sheffield, M.; Erives, H. [Opto-Knowledge Systems, Inc. (United States); Barhen, J. [Oak Ridge National Lab., TN (United States)

1997-04-01T23:59:59.000Z

133

Quantum gravity and "singularities"  

E-Print Network (OSTI)

The paper concerns the fictitious entanglement of the so-called ``singularities'' in problems, pertaining to quantum gravity, due, in point of fact, to the way we try to employ, in that context, differential geometry, the latter being associated, in effect, by far, classically (:smooth manifolds), on the basis of an erroneous correspondence between what we may call/understand, as ``physical space'' and the ``cartesian-newtonian'' one.

Anastasios Mallios

2004-05-20T23:59:59.000Z

134

Lorentz Breaking and Gravity  

E-Print Network (OSTI)

Gravitational theories with Lorentz violation must account for a number of possible features in order to be consistent theoretically and phenomenologically. A brief summary of these features is given here. They include evasion of a no-go theorem, connections between spontaneous Lorentz breaking and diffeomorphism breaking, the appearance of massless Nambu-Goldstone modes and massive Higgs modes, and the possibility of a Higgs mechanism in gravity.

R. Bluhm

2013-07-22T23:59:59.000Z

135

Gravity, Dimension, Equilibrium, & Thermodynamics  

E-Print Network (OSTI)

Is it actually possible to interpret gravitation as space's property in a pure classical way. Then, we note that extended self-gravitating system equilibrium depends directly on the number of dimension of the space in which it evolves. Given those precisions, we review the principal thermodynamical knowledge in the context of classical gravity with arbitrary dimension of space. Stability analyses for bounded 3D systems, namely the Antonov instability paradigm, are then rapproched to some amazing properties of globular clusters and galaxies.

Jerome Perez

2006-03-30T23:59:59.000Z

136

The Particle Adventure | What holds it together? | Gravity  

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

holds it together? > Gravity Gravity What about gravity? Gravity is weird. It is clearly one of the fundamental interactions, but the Standard Model cannot satisfactorily explain...

137

Preparation of Residual Gravity Maps for the Southern Cascade Mountains, Washington Using Fourier Analysis  

DOE Green Energy (OSTI)

This report represents a continuation of gravity work in the Cascade Mountains of Washington supported by the Division of Geology and Earth Resources since 1974. The purpose of this research has been collection of baseline gravity data for use in geothermal resource evaluation. Results of the Division's gravity studies to date are given in Danes and Phillips (1983a, 1983b). One of the problems encountered when analyzing gravity data is distinguishing between those parts of the data that represent geologic structures of interest, and those that do not. In many cases, the features of interest are relatively small, near-surface features, such as those sought in mineral, petroleum, or geothermal exploration. Gravity anomalies caused by such structures may be distorted or masked by anomalies caused by larger, deeper geologic structures. Gravity anomalies caused by relatively shallow, small geologic structures are termed residual anomalies. Those due to broad, deep-seated features can be described as regional anomalies. The purpose of this report is to describe a Fourier analysis method for separating residual and regional gravity anomalies from a complete Bouguer gravity anomaly field. The technique has been applied to gravity data from the Southern Cascade Mountains, Washington. Residual gravity anomaly maps at a scale of 1:250,000 are presented for various regional wavelength filters, and a power spectrum of the frequency components in the South Cascade gravity data is displayed. No attempt is made to interpret the results of this study in terms of geologic structures.

Dishberger, Debra McLean

1983-04-01T23:59:59.000Z

138

Entropic Gravity in Rindler Space  

E-Print Network (OSTI)

We show that Rindler horizons are entropic screens and gravity is an entropic force in Rindler space by deriving the Verlinde entropy formula from the focusing of light due to a mass close to the horizon. Consequently, gravity is also entropic in the near horizon regions of Schwarzschild and de Sitter space-times. In different limits, the entropic nature of gravity in Rindler space leads to the Bekenstein entropy bound and the uncertainty principle.

Halyo, Edi

2011-01-01T23:59:59.000Z

139

Entropic Gravity in Rindler Space  

E-Print Network (OSTI)

We show that Rindler horizons are entropic screens and gravity is an entropic force in Rindler space by deriving the Verlinde entropy formula from the focusing of light due to a mass close to the horizon. Consequently, gravity is also entropic in the near horizon regions of Schwarzschild and de Sitter space-times. In different limits, the entropic nature of gravity in Rindler space leads to the Bekenstein entropy bound and the uncertainty principle.

Edi Halyo

2011-04-13T23:59:59.000Z

140

Cascading gravity is ghost free  

SciTech Connect

We perform a full perturbative stability analysis of the 6D cascading gravity model in the presence of 3-brane tension. We demonstrate that for sufficiently large tension on the (flat) 3-brane, there are no ghosts at the perturbative level, consistent with results that had previously only been obtained in a specific 5D decoupling limit. These results establish the cascading gravity framework as a consistent infrared modification of gravity.

Rham, Claudia de [Departement de Physique Theorique, Universite de Geneve, 24 Quai E. Ansermet, CH-1211 Geneve (Switzerland); Khoury, Justin [Center for Particle Cosmology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6395 (United States); Tolley, Andrew J. [Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo, ON, N2L 2Y5 (Canada)

2010-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

D-dimensional log gravity  

SciTech Connect

We study Einstein gravity in dimensions D{>=}4 modified by curvature squared at critical point where the theory contains only massless gravitons. We show that at the critical point a new mode appears leading to a logarithmic gravity in the theory. The corresponding logarithmic solution may provide a gravity description of logarithmic conformal field theories (CFT) in higher dimensions. We note also that for special values of the parameters of the theory, the model admits solutions with nonrelativistic isometries.

Alishahiha, Mohsen; Fareghbal, Reza [School of physics, Institute for Research in Fundamental Sciences (IPM), P. O. Box 19395-5531, Tehran (Iran, Islamic Republic of)

2011-04-15T23:59:59.000Z

142

Ground Gravity Survey At Mokapu Penninsula Area (Thomas, 1986) | Open  

Open Energy Info (EERE)

Ground Gravity Survey At Mokapu Penninsula Area Ground Gravity Survey At Mokapu Penninsula Area (Thomas, 1986) Exploration Activity Details Location Mokapu Penninsula Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes A separate geophysical analysis performed on the Koolau caldera area (Kauahikaua, 1981 a) synthesized existing self-potential, gravity, seismic and aeromagnetic data with recently acquired resistivity soundings. An analysis of the observed remnant magnetization within the caldera complex suggested that subsurface temperatures ranged from less than 300degrees C to no more than 540degrees C. The resistivity data indicated that the electrical basement, to a depth of 900 m, had resistivities ranging from 42 ohm.m to more than 1000 ohm.m, which is considered to be within the

143

Is Gravity an Entropic Force?  

E-Print Network (OSTI)

The remarkable connections between gravity and thermodynamics seem to imply that gravity is not fundamental but emergent, and in particular, as Verlinde suggested, gravity is probably an entropic force. In this paper, we will argue that the idea of gravity as an entropic force is debatable. It is shown that there is no convincing analogy between gravity and entropic force in Verlinde's example. Neither holographic screen nor test particle satisfies all requirements for the existence of entropic force in a thermodynamics system. Furthermore, we show that the entropy increase of the screen is not caused by its statistical tendency to increase entropy as required by the existence of entropic force, but in fact caused by gravity. Therefore, Verlinde's argument for the entropic origin of gravity is problematic. In addition, we argue that the existence of a minimum size of spacetime, together with the Heisenberg uncertainty principle in quantum theory, may imply the fundamental existence of gravity as a geometric property of spacetime. This may provide a further support for the conclusion that gravity is not an entropic force.

Shan Gao

2010-02-13T23:59:59.000Z

144

Topological methods in quantum gravity.  

E-Print Network (OSTI)

??The main technical problem with background independent approaches to quantum gravity is inapplicability of standard quantum field theory methods. New methods are needed which would… (more)

Starodubtsev, Artem

2005-01-01T23:59:59.000Z

145

Discrete gravity models and Loop Quantum Gravity: a short review  

E-Print Network (OSTI)

We review the relation between loop quantum gravity on a fixed graph and discrete models of gravity. We compare Regge and twisted geometries, and discuss discrete actions based on twisted geometries and on the discretization of the Plebanski action. We discuss the role of discrete geometries in the spin foam formalism, with particular attention to the definition of the simplicity constraints.

Dupuis, Maite; Speziale, Simone

2012-01-01T23:59:59.000Z

146

Gravity wraps Higgs boson  

E-Print Network (OSTI)

It is shown that, under a conformal transformation with reference to the Higgs field, the Higgs boson can be completely decoupled from electroweak interactions with no apparent change in known properties of leptons, quarks and vector bosons. Higgs boson becomes part of a scalar-tensor gravity which can be relevant for Dark Energy. It interacts with matter sector via higher-dimensional terms (e.g. neutrino Majorana mass), and via the fields (of new physics) whose masses are not generated by the Higgs mechanism. Dark Matter and two-Higgs-doublet model are the simplest examples.

Durmus A. Demir

2011-10-17T23:59:59.000Z

147

Deformed Einstein Gravity  

Science Conference Proceedings (OSTI)

We introduce the necessary concepts for an algebraic construction of a gravity theory on noncommutative spaces. The ??deformed diffeomorphisms are studied and a tensor calculus is defined. This leads to a deformed Einstein?Hilbert action which is invariant with respect to deformed diffeomorphisms. The dynamical variable is the vierbein field. The deformed action is a deformation of the usual Einstein?Hilbert action and reduces to it in the limit where the noncommutativity vanishes. This contribution is based on joint work with P. Aschieri

Frank Meyer

2006-01-01T23:59:59.000Z

148

Gravity-Driven Intrusions in Stratified Fluids  

E-Print Network (OSTI)

5.5.1 Five interleaving interfacial gravity currents 5.5.2Ten interleaving interfacial gravity currents . 5.6in Iceland showing multiple gravity-driven intrusions c ´

Maurer, Benjamin D.

2011-01-01T23:59:59.000Z

149

The role of information in gravity  

E-Print Network (OSTI)

It is argued that particle-specific information on energy-momentum adjusts the strength of gravity. This form of gravity has no free parameters, preserves Einstein gravity locally and predicts 6 times stronger accelerations on galaxy scales.

M. Spaans

2009-03-25T23:59:59.000Z

150

BioSAR Airborne Biomass Sensing System  

DOE Green Energy (OSTI)

This CRADA was developed to enable ORNL to assist American Electronics, Inc. test a new technology--BioSAR. BioSAR is a an airborne, low frequency (80-120 MHz {approx} FM radio frequencies) synthetic aperture radar (SAR) technology which was designed and built for NASA by ZAI-Amelex under Patrick Johnson's direction. At these frequencies, leaves and small branches are nearly transparent and the majority of the energy reflected from the forest and returned to the radar is from the tree trunks. By measuring the magnitude of the back scatter, the volume of the tree trunk and therefore the biomass of the trunks can be inferred. The instrument was successfully tested on tropical rain forests in Panama. Patrick Johnson, with American Electronics, Inc received a Phase II SBIR grant from DOE Office of Climate Change to further test and refine the instrument. Mr Johnson sought ORNL expertise in measuring forest biomass in order for him to further validate his instrument. ORNL provided ground truth measurements of forest biomass at three locations--the Oak Ridge Reservation, Weyerhaeuser Co. commercial pine plantations in North Carolina, and American Energy and Power (AEP) Co. hardwood forests in southern Ohio, and facilitated flights over these forests. After Mr. Johnson processed the signal data from BioSAR instrument, the processed data were given to ORNL and we attempted to derive empirical relationships between the radar signals and the ground truth forest biomass measurements using standard statistical techniques. We were unsuccessful in deriving such relationships. Shortly before the CRADA ended, Mr Johnson discovered that FM signal from local radio station broadcasts had interfered with the back scatter measurements such that the bulk of the signal received by the BioSAR instrument was not backscatter from the radar but rather was local radio station signals.

Graham, R.L.; Johnson, P.

2007-05-24T23:59:59.000Z

151

Lovelock gravity from entropic force  

E-Print Network (OSTI)

In this paper, we first generalize the formulation of entropic gravity to (n+1)-dimensional spacetime. Then, we propose an entropic origin for Gauss-Bonnet gravity and more general Lovelock gravity in arbitrary dimensions. As a result, we are able to derive Newton's law of gravitation as well as the corresponding Friedmann equations in these gravity theories. This procedure naturally leads to a derivation of the higher dimensional gravitational coupling constant of Friedmann/Einstein equation which is in complete agreement with the results obtained by comparing the weak field limit of Einstein equation with Poisson equation in higher dimensions. Our study shows that the approach presented here is powerful enough to derive the gravitational field equations in any gravity theory. PACS: 04.20.Cv, 04.50.-h, 04.70.Dy.

A. Sheykhi; H. Moradpour; N. Riazi

2011-09-11T23:59:59.000Z

152

Gravity Waves in the Sun  

E-Print Network (OSTI)

We present numerical simulations of penetrative convection and gravity wave excitation in the Sun. Gravity waves are self-consistently generated by a convective zone overlying a radiative interior. We produce power spectra for gravity waves in the radiative region as well as estimates for the energy flux of gravity waves below the convection zone. We calculate a peak energy flux in waves below the convection zone to be three orders of magnitude smaller than previous estimates for m=1. The simulations show that the linear dispersion relation is a good approximation only deep below the convective-radiative boundary. Both low frequency propagating gravity waves as well as higher frequency standing modes are generated; although we find that convection does not continually drive the standing g-mode frequencies.

Tamara M. Rogers; Gary A. Glatzmaier

2005-08-25T23:59:59.000Z

153

Introductory Remarks: ARM AVP Workshop on Advances in Airborne...  

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

Advances in Airborne Instrumentation Warren Wiscombe ARM Chief Scientist Brookhaven National Lab ARM ARM Atmospheric Radiation Measurement Atmospheric Radiation Measurement...

154

New Sampling Methods for Airborne Microorganisms  

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

New Sampling Methods for Airborne Microorganisms New Sampling Methods for Airborne Microorganisms Speaker(s): Klaus Willeke Date: February 27, 2001 - 12:00pm Location: Bldg 90 Seminar Host/Point of Contact: David Faulkner Klaus Willeke and his international team of engineers, physicists, microbiologists, industrial hygienists and environmental scientists have worked for about 15 years on the development of new methods for sampling airborne microorganisms. The following topics will be highlighted: long-term bioaerosol sampling into liquid by swirling air motion ("Biosampler"); personal aerosol sampling with low wind sensitivity and highfilter deposit uniformity ("Button Aerosol Sampler"); collection of microorganisms by electrostatic means; source testing as a predictor for microorganism release from surfaces; particle concentrating from large air

155

Intercomparison of Water Vapor Data Measured with Lidar during IHOP_2002. Part II: Airborne-to-Airborne Systems  

Science Conference Proceedings (OSTI)

The dataset of the International H2O Project (IHOP_2002) gives the first opportunity for direct intercomparisons of airborne water vapor lidar systems and allows very important conclusions to be drawn for future field campaigns. Three airborne ...

Andreas Behrendt; Volker Wulfmeyer; Thorsten Schaberl; Hans-Stefan Bauer; Christoph Kiemle; Gerhard Ehret; Cyrille Flamant; Susan Kooi; Syed Ismail; Richard Ferrare; Edward V. Browell; David N. Whiteman

2007-01-01T23:59:59.000Z

156

Ground Gravity Survey At Clear Lake Area (Skokan, 1993) | Open Energy  

Open Energy Info (EERE)

Ground Gravity Survey At Clear Lake Area (Skokan, 1993) Ground Gravity Survey At Clear Lake Area (Skokan, 1993) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Clear Lake Area (Skokan, 1993) Exploration Activity Details Location Clear Lake Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes A detailed gravity survey (Isherwood, 1975) was undertaken as a follow-up to a regional gravity survey of the area in order to detail a low in the Clear Lake volcanics. The low (Fig. 5 ) was thought to be caused by an intrusion of molten rock which would be mass deficient. Modeling and interpretation indicated a+K139 chamber-like feature with a radius of approximately 7 km within 7-8 km of the surface. References

157

Ground Gravity Survey At Raft River Geothermal Area (1957-1961) | Open  

Open Energy Info (EERE)

Ground Gravity Survey At Raft River Geothermal Area (1957-1961) Ground Gravity Survey At Raft River Geothermal Area (1957-1961) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Raft River Geothermal Area (1957-1961) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Ground Gravity Survey Activity Date 1957 - 1961 Usefulness not indicated DOE-funding Unknown Notes From 1957 to 1961 a regional gravity survey was made over the northern part of the Great Salt Lake Desert and adjacent areas in Utah, eastern Nevada, and southeastern Idaho. A total of 1040 stations were taken over an area of about 7000 square miles. The results were compiled as a Bouguer gravity anomaly map with a contour interval of 2 mgal. The Bouguer values ranged

158

Ground Gravity Survey At Valles Caldera - Redondo Area (Wilt & Haar, 1986)  

Open Energy Info (EERE)

Gravity Survey At Valles Caldera - Redondo Area (Wilt & Haar, 1986) Gravity Survey At Valles Caldera - Redondo Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Valles Caldera - Redondo Area (Wilt & Haar, 1986) Exploration Activity Details Location Valles Caldera - Redondo Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting gravity observations along profiles A--A' and B--B' (Talwani et al., 1959). Densities of 2.12, 2.40, and 2.65 g/cm a were used for modeling the near-surface caldera fill, the underlying volcanics, and the basement sections, respectively (Fig. 8). Although correlation with

159

Ground Gravity Survey At Dixie Valley Geothermal Field Area (Blackwell, Et  

Open Energy Info (EERE)

Blackwell, Et Blackwell, Et Al., 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Dixie Valley Geothermal Field Area (Blackwell, Et Al., 2009) Exploration Activity Details Location Dixie Valley Geothermal Field Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes "The gravity data are described by (Blackwell et al., 1999; 2002). On a basin-wide scale the gravity low in Dixie Valley is strongly asymmetrical from east to west. The west side is relatively well-defined by rapid horizontal changes in the gravity anomaly value, whereas along the east side horizontal changes are more subdued and often consist of several steps. The horizontal gradient of the gravity field has proved most useful

160

Will multiple probes of dark energy find modified gravity?  

SciTech Connect

One of the most pressing issues in cosmology is whether general relativity (GR) plus a dark sector is the underlying physical theory or whether a modified gravity model is needed. Upcoming dark energy experiments designed to probe dark energy with multiple methods can address this question by comparing the results of the different methods in constraining dark energy parameters. Disagreement would signal the breakdown of the assumed model (GR plus dark energy). We study the power of this consistency test by projecting constraints in the w{sub 0}-w{sub a} plane from the four different techniques of the Dark Energy Survey in the event that the underlying true model is modified gravity. We find that the standard technique of looking for overlap has some shortcomings, and we propose an alternative, more powerful Multidimensional Consistency Test. We introduce the methodology for projecting whether a given experiment will be able to use this test to distinguish a modified gravity model from GR.

Shapiro, Charles [Institute of Cosmology and Gravitation, Portsmouth, PO1 3FX (United Kingdom); Dodelson, Scott [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637 (United States); Kavli Institute for Cosmological Physics, Chicago, Illinois 60637 (United States); Hoyle, Ben [Institut de Ciencies del Cosmos, Barcelona (Spain); Samushia, Lado [Institute of Cosmology and Gravitation, Portsmouth, PO1 3FX (United Kingdom); National Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, GE-0160 Tbilisi (Georgia); Flaugher, Brenna [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

2010-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Hall viscosity from gauge/gravity duality  

E-Print Network (OSTI)

In (2+1)-dimensional systems with broken parity, there exists yet another transport coefficient, appearing at the same order as the shear viscosity in the hydrodynamic derivative expansion. In condensed matter physics, it is referred to as "Hall viscosity". We consider a simple holographic realization of a (2+1)-dimensional isotropic fluid with broken spatial parity. Using techniques of fluid/gravity correspondence, we uncover that the holographic fluid possesses a nonzero Hall viscosity, whose value only depends on the near-horizon region of the background. We also write down a Kubo's formula for the Hall viscosity. We confirm our results by directly computing the Hall viscosity using the formula.

Omid Saremi; Dam Thanh Son

2011-03-24T23:59:59.000Z

162

Quantum Histories and Quantum Gravity  

E-Print Network (OSTI)

This paper reviews the histories approach to quantum mechanics. This discussion is then applied to theories of quantum gravity. It is argued that some of the quantum histories must approximate (in a suitable sense) to classical histories, if the correct classical regime is to be recovered. This observation has significance for the formulation of new theories (such as quantum gravity theories) as it puts a constraint on the kinematics, if the quantum/classical correspondence principle is to be preserved. Consequences for quantum gravity, particularly for Lorentz symmetry and the idea of "emergent geometry", are discussed.

Joe Henson

2009-01-26T23:59:59.000Z

163

Oklahoma, Kansas, Missouri Refinery District API Gravity ...  

U.S. Energy Information Administration (EIA)

Oklahoma, Kansas, Missouri Refinery District API Gravity (Weighted Average) of Crude Oil Input to Refineries (Degree)

164

Intrusive gravity currents in two-layer  

E-Print Network (OSTI)

Intrusive gravity currents in two-layer stratified media Morris R. Flynn & Paul F. Linden Dept to as a gravity current · In contrast to waves, gravity currents transport significant mass (e.g. fluid parcels, sediment, insects, etc.) Introduction Gravity currents in the environment www

Flynn, Morris R.

165

Spin-gravity coupling and gravity-induced quantum phases  

E-Print Network (OSTI)

External gravitational fields induce phase factors in the wave functions of particles. The phases are exact to first order in the background gravitational field, are manifestly covariant and gauge invariant and provide a useful tool for the study of spin-gravity coupling and of the optics of particles in gravitational or inertial fields. We discuss the role that spin-gravity coupling plays in particular problems.

Giorgio Papini

2007-09-06T23:59:59.000Z

166

PPN-limit of Fourth Order Gravity inspired by Scalar-Tensor Gravity  

E-Print Network (OSTI)

Based on the {\\it dynamical} equivalence between higher order gravity and scalar-tensor gravity the PPN-limit of fourth order gravity is discussed. We exploit this analogy developing a fourth order gravity version of the Eddington PPN-parameters. As a result, Solar System experiments can be reconciled with higher order gravity, if physical constraints descending from experiments are fulfilled.

S. Capozziello; A. Troisi

2005-07-22T23:59:59.000Z

167

Gravity's Cosmic ShadowsGravity's Cosmic Shadows A Mathematical UnveilingA Mathematical Unveiling  

E-Print Network (OSTI)

Gravity's Cosmic ShadowsGravity's Cosmic Shadows A Mathematical UnveilingA Mathematical Unveiling of gravity on light SUNSUN #12;Gravitational Lensing - action of gravity on light SUNSUN #12;Gravitational Lensing - action of gravity on light SUNSUN nn 1801: Johann von1801: Johann von SoldnerSoldner (Newtonian

Weinberger, Hans

168

ARMAR: An Airborne Rain-Mapping Radar  

Science Conference Proceedings (OSTI)

A new airborne rain-mapping radar (ARMAR) has been developed by NASA and the Jet Propulsion Laboratory for operation on the NASA Ames DC-8 aircraft. The radar operates at 13.8 GHz, the frequency to be used by the radar on the Tropical Rainfall ...

S. L. Durden; E. Im; F. K. Li; W. Ricketts; A. Tanner; W. Wilson

1994-06-01T23:59:59.000Z

169

Geophysical Techniques | Open Energy Information  

Open Energy Info (EERE)

Geophysical Techniques Geophysical Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Geophysical Techniques Details Activities (2) Areas (1) Regions (0) NEPA(4) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: None Parent Exploration Technique: Exploration Techniques Information Provided by Technique Lithology: may be inferred Stratigraphic/Structural: may be inferred Hydrological: may be inferred Thermal: may be inferred Dictionary.png Geophysical Techniques: Geophysics is the study of the structure and composition of the earth's interior. Other definitions:Wikipedia Reegle Introduction Geophysical techniques measure physical phenomena of the earth such as gravity, magnetism, elastic waves, electrical and electromagnetic waves.

170

Gravity survey of the Cove Fort-Sulphurdale KGRA and the north Mineral Mountains area, Millard and Beaver Counties, Utah  

DOE Green Energy (OSTI)

During the summers of 1975 and 1976, a gravity survey was conducted in the Cove Fort-Sulphurdale KGRA and north Mineral Mountains area, Millard and Beaver Counties, Utah. The survey consisted of 671 gravity stations covering an area of about 1300 km{sup 2}, and included two orthogonal gravity profiles traversing the area. The gravity data are presented as a terrain-corrected Bouguer gravity anomaly map with a contour interval of 1 mgal and as an isometric three-dimensional gravity anomaly surface. Selected anomaly separation techniques were applied to the hand-digitized gravity data (at 1-km intervals on the Universal Transverse Mercator grid) in both the frequency and space domains, including Fourier decomposition, second vertical derivative, strike-filter, and polynomial fitting analysis, respectively.

Brumbaugh, W.D.; Cook, K.L.

1977-08-01T23:59:59.000Z

171

Numerical Dispersion of Gravity Waves  

Science Conference Proceedings (OSTI)

When atmospheric gravity waves are simulated in numerical models, they are not only dispersive for physical but also for numerical reasons. Their wave properties (e.g., damping or propagation speed and direction) can depend on grid spacing as ...

Guido Schroeder; K. Heinke Schlünzen

2009-12-01T23:59:59.000Z

172

Critical Gravity in Four Dimensions  

SciTech Connect

We study four-dimensional gravity theories that are rendered renormalizable by the inclusion of curvature-squared terms to the usual Einstein action with a cosmological constant. By choosing the parameters appropriately, the massive scalar mode can be eliminated and the massive spin-2 mode can become massless. This ''critical'' theory may be viewed as a four-dimensional analogue of chiral topologically massive gravity, or of critical 'new massive gravity' with a cosmological constant, in three dimensions. We find that the on-shell energy for the remaining massless gravitons vanishes. There are also logarithmic spin-2 modes, which have positive energy. The mass and entropy of standard Schwarzschild-type black holes vanish. The critical theory might provide a consistent toy model for quantum gravity in four dimensions.

Lue, H. [China Economics and Management Academy, Central University of Finance and Economics, Beijing 100081 (China); Institute for Advanced Study, Shenzhen University, Nanhai Avenue 3688, Shenzhen 518060 (China); Pope, C. N. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); DAMTP, Centre for Mathematical Sciences, Cambridge University, Wilberforce Road, Cambridge CB3 OWA (United Kingdom)

2011-05-06T23:59:59.000Z

173

Structure formation in modified gravity  

Science Conference Proceedings (OSTI)

We pursue a (1+3) ?covariant analysis of cosmological peculiar velocity of pressure?free matter induced by the matter density perturbations in modified f(R) gravity theories. Instead of working in a quasi?Newtonian Eulerian frame

D. M. Solomons; P. K. S. Dunsby; S. Carloni

2009-01-01T23:59:59.000Z

174

Identifying Student Concepts of Gravity.  

E-Print Network (OSTI)

??This paper discusses a survey developed to investigate student concepts of "gravity" among AST 109 astronomy students and pre-service K-12 teachers. Survey questions were developed… (more)

Feeley, Roger Eastman

2007-01-01T23:59:59.000Z

175

Gravity Currents in Aquatic Canopies  

E-Print Network (OSTI)

A lock exchange experiment is used to investigate the propagation of gravity currents through a random array of rigid, emergent cylinders which represents a canopy of aquatic plants. As canopy drag increases, the propagating ...

Tanino, Yukie

176

Momentum Balance of Gravity Flows  

Science Conference Proceedings (OSTI)

A unified scale analysis of the momentum balance of downslope gravity flows is developed to organize previous theories for the case of negligible ambient flow and fixed temperature deficit scale. The values of several nondimensional parameters ...

L. Mahrt

1982-12-01T23:59:59.000Z

177

Quench cooling under reduced gravity  

E-Print Network (OSTI)

We report the quench cooling experiments performed with liquid O2 under different levels of gravity simulated with the magnetic gravity compensation. A copper disk is quenched from 270K to 90K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the isolation effect of the gas surrounding the disk. The liquid subcooling is shown to drastically improuve the heat exchange thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that such type of experiments cannot be used for the analysis of the critical heat flux (CHF) of the boiling crisis. The minimum heat flux (MHF) of boiling is analyzed instead.

Chatain, D; Nikolayev, V S; Beysens, D

2013-01-01T23:59:59.000Z

178

Attractions of Affine Quantum Gravity  

E-Print Network (OSTI)

All attempts to quantize gravity face several difficult problems. Among these problems are: (i) metric positivity (positivity of the spatial distance between distinct points), (ii) the presence of anomalies (partial second-class nature of the quantum constraints), and (iii) perturbative nonrenormalizability (the need for infinitely many distinct counterterms). In this report, a relatively nontechnical discussion is presented about how the program of affine quantum gravity proposes to deal with these problems.

John R. Klauder

2004-11-10T23:59:59.000Z

179

Lectures on Screened Modified Gravity  

E-Print Network (OSTI)

The acceleration of the expansion of the Universe has led to the construction of Dark Energy models where a light scalar field may have a range reaching up to cosmological scales. Screening mechanisms allow these models to evade the tight gravitational tests in the solar system and the laboratory. I will briefly review some of the salient features of screened modified gravity models of the chameleon, dilaton or symmetron types using $f(R)$ gravity as a template.

Philippe Brax

2012-11-22T23:59:59.000Z

180

A Higher-Order Ray Approximation Applied to Orographic Gravity Waves: Gaussian Beam Approximation  

Science Conference Proceedings (OSTI)

Ray techniques are a promising tool for developing orographic gravity wave drag schemes. However, the modeling of the propagation of orographic waves using standard ray theory in realistic background wind conditions usually encounters several ...

Manuel Pulido; Claudio Rodas

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Observational Tests of Modified Gravity  

E-Print Network (OSTI)

Modified gravity theories have richer observational consequences for large-scale structure than conventional dark energy models, in that different observables are not described by a single growth factor even in the linear regime. We examine the relationships between perturbations in the metric potentials, density and velocity fields, and discuss strategies for measuring them using gravitational lensing, galaxy cluster abundances, galaxy clustering/dynamics and the ISW effect. We show how a broad class of gravity theories can be tested by combining these probes. A robust way to interpret observations is by constraining two key functions: the ratio of the two metric potentials, and the ratio of the Gravitational ``constant'' in the Poisson equation to Newton's constant. We also discuss quasilinear effects that carry signatures of gravity, such as through induced three-point correlations. Clustering of dark energy can mimic features of modified gravity theories and thus confuse the search for distinct signatures of such theories. It can produce pressure perturbations and anisotropic stresses, which breaks the equality between the two metric potentials even in general relativity. With these two extra degrees of freedom, can a clustered dark energy model mimic modified gravity models in all observational tests? We show with specific examples that observational constraints on both the metric potentials and density perturbations can in principle distinguish modifications of gravity from dark energy models. We compare our result with other recent studies that have slightly different assumptions (and apparently contradictory conclusions).

Bhuvnesh Jain; Pengjie Zhang

2007-09-17T23:59:59.000Z

182

Renormalizable Quantum Gravity in Low Energy without Violating Unitarity  

E-Print Network (OSTI)

We introduce new techniques that can preserve unitarity of the system including ghost particles. Negative norms of the particles can be involved in zero-norm states by constraints of the physical space. These are useful to apply the higher-derivative propagator for quantum gravity to suppress divergences of vacuum energy and graviton mass correction. The quantum effects are mainly depending on the ghost mass scale. As the scale can be chosen in any order, the observed cosmological constant is realized. Further, applying ghost partners for the standard model particles, quantum gravity with matter fields becomes renormalizable with power counting arguments.

Hajime Isimori

2010-10-25T23:59:59.000Z

183

Synthetic IR Scene Simulation of Air-borne Targets  

E-Print Network (OSTI)

IR scenes of high fidelity are needed to support the development and testing of various target detection and tracking techniques. It is impractical to test detection and tracking algorithms under all conceivable conditions. Therefore, to test the effectiveness of detection and tracking algorithms under variety of scenarios, synthetic IR scenes are generated. For air-borne targets, the presence of clouds plays an important role, since they affect most IR sensors. We propose, a mod- ification of original Gardner's Method [3], in order to generate clouds of richer spectral content. We also ex- plore an algorithm based on self-similarity [5] for cloud texture generation. Synthetic IR cloud images generated by our scene simulation software are radiometrically accurate and have typical cloud texture variations. We use Modtran J.O for radiometric calculation and VRML (Virtual Reality Modeling Language) for scene rendering.

Shankar T. More; Avinash A. Pandit; Avinash A. P; S. N. Merchant; U. B. Desai

2002-01-01T23:59:59.000Z

184

Ground Gravity Survey At Truckhaven Area (Layman Energy Associates, 2009) |  

Open Energy Info (EERE)

Truckhaven Area (Layman Energy Associates, 2009) Truckhaven Area (Layman Energy Associates, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Truckhaven Area (Layman Energy Associates, 2009) Exploration Activity Details Location Truckhaven Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes The area of coverage for the DOE-funded geophysical surveys is shown in Figure 9. The 95 magnetotelluric (MT) soundings cover a central area of about 80 square kilometers. The 126 gravity stations extend over a broader area of about 150 square kilometers, centered on the same area covered by the MT soundings. A detailed description of the instrumentation and data acquisition procedures used for both surveys is provided in GSY-USA, Inc.

185

Analyzing Options for Airborne Emergency Wireless Communications  

SciTech Connect

In the event of large-scale natural or manmade catastrophic events, access to reliable and enduring commercial communication systems is critical. Hurricane Katrina provided a recent example of the need to ensure communications during a national emergency. To ensure that communication demands are met during these critical times, Idaho National Laboratory (INL) under the guidance of United States Strategic Command has studied infrastructure issues, concerns, and vulnerabilities associated with an airborne wireless communications capability. Such a capability could provide emergency wireless communications until public/commercial nodes can be systematically restored. This report focuses on the airborne cellular restoration concept; analyzing basic infrastructure requirements; identifying related infrastructure issues, concerns, and vulnerabilities and offers recommended solutions.

Michael Schmitt; Juan Deaton; Curt Papke; Shane Cherry

2008-03-01T23:59:59.000Z

186

Remote Sensing Techniques | Open Energy Information  

Open Energy Info (EERE)

Remote Sensing Techniques Remote Sensing Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Remote Sensing Techniques Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Remote Sensing Techniques Exploration Sub Group: None Parent Exploration Technique: Exploration Techniques Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Remote Sensing Techniques: Remote sensing utilizes satellite and/or airborne based sensors to collect information about a given object or area. Remote sensing data collection methods can be passive or active. Passive sensors (e.g., spectral imagers) detect natural radiation that is emitted or reflected by the object or area

187

GROA AIRBORNE RELEASE DISPERSION FACTOR CALCULATION  

Science Conference Proceedings (OSTI)

The purpose of this document is to calculate airborne release dispersion factors ({chi}/Q) for the surface and subsurface facilities at the Geological Repository Operations Area (GROA). The calculated {chi}/Q values may be used to estimate radiological consequences to workers for potential releases from normal operations and event sequences for License Application. The scope of this document is to provide estimates of {chi}/Q values at potential onsite receptors from facility releases, under normal operating conditions and event sequences.

J. Wang

2005-03-21T23:59:59.000Z

188

A Distinction Technique Between Volcanic And Tectonic Depression Structures  

Open Energy Info (EERE)

Distinction Technique Between Volcanic And Tectonic Depression Structures Distinction Technique Between Volcanic And Tectonic Depression Structures Based On The Restoration Modeling Of Gravity Anomaly- A Case Study Of The Hohi Volcanic Zone, Central Kyushu, Japan Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Distinction Technique Between Volcanic And Tectonic Depression Structures Based On The Restoration Modeling Of Gravity Anomaly- A Case Study Of The Hohi Volcanic Zone, Central Kyushu, Japan Details Activities (0) Areas (0) Regions (0) Abstract: In this study, we propose a numerical modeling technique which restores the gravity anomaly of tectonic origin and identifies the gravity low of caldera origin. The identification is performed just by comparing the restored gravity anomalies with the observed gravity anomalies, thus we

189

Dilaton Gravity, Poisson Sigma Models and Loop Quantum Gravity  

E-Print Network (OSTI)

Spherically symmetric gravity in Ashtekar variables coupled to Yang-Mills theory in two dimensions and its relation to dilaton gravity and Poisson sigma models are discussed. After introducing its loop quantization, quantum corrections for inverse triad components are shown to provide a consistent deformation without anomalies. The relation to Poisson sigma models provides a covariant action principle of the quantum corrected theory with effective couplings. Results are also used to provide loop quantizations of spherically symmetric models in arbitrary D space-time dimensions.

Martin Bojowald; Juan D. Reyes

2008-10-28T23:59:59.000Z

190

Airborne Tactical Free-Electron Laser  

Science Conference Proceedings (OSTI)

The goal of 100 kilowatts (kW) of directed energy from an airborne tactical platform has proved challenging due to the size and weight of most of the options that have been considered. However, recent advances in Free-Electron Lasers appear to offer a solution along with significant tactical advantages: a nearly unlimited magazine, time structures for periods from milliseconds to hours, radar like functionality, and the choice of the wavelength of light that best meets mission requirements. For an Airborne Tactical Free-Electron Laser (ATFEL) on a platforms such as a Lockheed C-130J-30 and airships, the two most challenging requirements, weight and size, can be met by generating the light at a higher harmonic, aggressively managing magnet weights, managing cryogenic heat loads using recent SRF R&D results, and using FEL super compact design concepts that greatly reduce the number of components. The initial R&D roadmap for achieving an ATFEL is provided in this paper. Performing this R&D is expected to further reduce the weight, size and power requirements for the FELs the Navy is currently developing for shipboard applications, as well as providing performance enhancements for the strategic airborne MW class FELs. The 100 kW ATFEL with its tactical advantages may prove sufficiently attractive for early advancement in the queue of deployed FELs.

Roy Whitney; George Neil

2007-02-01T23:59:59.000Z

191

Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2004) | Open  

Open Energy Info (EERE)

Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2004) Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2004) Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D. A. Sanchez, J. Nathwani (2004) Geothermal Resource Exploration And Definition Projects Retrieved from "http://en.openei.org/w/index.php?title=Ground_Gravity_Survey_At_Cove_Fort_Area_(Warpinski,_Et_Al.,_2004)&oldid=598130" Categories: Exploration Activities DOE Funded Activities

192

Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al.,  

Open Energy Info (EERE)

Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al., Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al., 2002) Exploration Activity Details Location Under Steamboat Springs Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes This project consisted of (1) a 3-D surface seismic survey conducted in the fall of 2000, (2) a micro-seismic survey run from November 2000 to April 200 1, and (3) a gravity survey conducted in April and May 2001. The 3-D surface seismic data are still being processed at this time, but initial results indicate that there are two major lineations of high velocity

193

Modified gravity from the quantum part of the metric  

E-Print Network (OSTI)

It is shown that if a metric in quantum gravity can be decomposed as a sum of classical and quantum parts then Einstein quantum gravity looks approximately like modified gravity with a nonminimal interaction between gravity and matter.

Vladimir Dzhunushaliev; Vladimir Folomeev; Burkhard Kleihaus; Jutta Kunz

2013-12-01T23:59:59.000Z

194

Source Apportionment of Airborne Particulate Matter using Inorganic...  

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

organic aerosol (SOA), airborne soil, other SOA, diesel emissions, secondary sulfate, wood combustion, gasoline vehicle, and secondary nitrate contributing 6.9%, 12.8%, 3.7%,...

195

The Effect of Airborne Contaminants on Fuel Cell Performance...  

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

Energy Institute www.hnei.hawaii.edu The Effect of Airborne Contaminants on Fuel Cell Performance & Durability Richard Rocheleau Trent Molter William Collins Silvia Wessel Hawaii...

196

Enhanced and Inhibited Gravity Wave Spectra  

Science Conference Proceedings (OSTI)

Balloon measurements were used to investigate gravity waves in the upper troposphere and lower stratosphere above the Canadian high Arctic. The amount of gravity wave activity in the stratosphere was found to be related to particular ...

James A. Whiteway

1999-05-01T23:59:59.000Z

197

Questions and Answers - Does gravity affect atoms?  

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

and Answers Main Index Next Question (Can you crush atoms?) Can you crush atoms? Does gravity affect atoms? Gravity affects atoms the same way it affects all other matter. Every...

198

A Coherent Strategy for Qauntum Gravity  

E-Print Network (OSTI)

Affine quantum gravity, which differs notably from either string theory or loop quantum gravity, is briefly reviewed. Emphasis in this article is placed on the use of affine coherent states in this program.

John R. Klauder

2004-11-10T23:59:59.000Z

199

New models of f(R) theories of gravity  

SciTech Connect

We introduce new models of f(R) theories of gravity that are a generalization of Horava-Lifshitz gravity.

Kluson, J. [Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Kotlarska 2, 611 37, Brno (Czech Republic)

2010-03-15T23:59:59.000Z

200

New Models of f(R) Theories of Gravity  

E-Print Network (OSTI)

We introduce new models of f(R) theories of gravity that are generalization of Horava-Lifshitz gravity.

J. Kluson

2009-10-30T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

New Models of f(R) Theories of Gravity  

E-Print Network (OSTI)

We introduce new models of f(R) theories of gravity that are generalization of Horava-Lifshitz gravity.

Kluson, J

2009-01-01T23:59:59.000Z

202

Rapid gravity and gravity gradiometry terrain corrections via an adaptive quadtree mesh discretization  

E-Print Network (OSTI)

Rapid gravity and gravity gradiometry terrain corrections via an adaptive quadtree mesh discretization Kristofer Davis1,2 M. Andy Kass1 Yaoguo Li1 1 Center for Gravity, Electrical, and Magnetic Studies of gravity gradiometry surveys utilising an adaptive quadtree mesh discretization. The data- and terrain

203

Unification of Gravity and Electromagnetism Revisited  

E-Print Network (OSTI)

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

Partha Ghose

2013-02-14T23:59:59.000Z

204

A gravity term from spontaneous symmetry breaking  

E-Print Network (OSTI)

In this model, the gravity term in the Lagrangean comes from spontaneous symmetry breaking of an additional scalar quadruplet field $\\Upsilon$. The resulting gravitational field is approximate to one of the models of coframe gravity with parameters $\\rho_1 + 4 \\rho_2 = 0$, $\\rho_3 = 0$. This article includes an exact solution of coframe gravity with model parameters $\\rho_1 \

Mihai Moise

2014-01-02T23:59:59.000Z

205

Gravity Transform for Input Conditioning in  

E-Print Network (OSTI)

Gravity Transform for Input Conditioning in Brain Machine Interfaces António R. C. Paiva, José C. Motivation 2. Methods i. Gravity Transform ii. Modeling and output sensitivity analysis 3. Data Analysis #12;3 Outline 1. Motivation 2. Methods i. Gravity Transform ii. Modeling and output sensitivity analysis 3. Data

Paiva, António R. C.

206

Momentum Transport by Gravity Waves  

Science Conference Proceedings (OSTI)

The momentum flux by orographic gravity waves and the turbulent heat flux in wave-breaking regions are estimated from aircraft data from ALPEX. The fluxes on 6 March 1982 are controlled by low-level directional shear of the mean flow and ...

Jinwon Kim; L. Mahrt

1992-05-01T23:59:59.000Z

207

Overlap Fermion in External Gravity  

E-Print Network (OSTI)

On a lattice, we construct an overlap Dirac operator which describes the propagation of a Dirac fermion in external gravity. The local Lorentz symmetry is manifestly realized as a lattice gauge symmetry, while the general coordinate invariance is expected to be restored only in the continuum limit. The lattice index density in the presence of a gravitational field is calculated.

Hiroto So; Masashi Hayakawa; Hiroshi Suzuki

2006-10-04T23:59:59.000Z

208

Rheological measurements in reduced gravity  

Science Conference Proceedings (OSTI)

Rheology of fluidized beds and settling suspensions were studied experimentally in a series of reduced gravity parabolic flights aboard NASA’s KC?135 aircraft. Silica sands of two different size distributions were fluidized by air. The slurries were made using silica sand and Glycerol solution. The experimental set up incorporated instrumentation to measure the air flow rate

Sayavur I. Bakhtiyarov; Ruel A. Overfelt

1999-01-01T23:59:59.000Z

209

Gravity and the Fermion Mass  

E-Print Network (OSTI)

It is shown that gravity generates mass for the fermion. It does so by coupling directly with the spinor field. The coupling term is invariant with respect to the electroweak gauge group $ U(1) \\otimes SU(2)_L. $ It replaces the fermion mass term $ m\\bar{\\psi} \\psi $.

Kenneth Dalton

2004-09-08T23:59:59.000Z

210

Fundamental decoherence in quantum gravity  

E-Print Network (OSTI)

A recently introduced discrete formalism allows to solve the problem of time in quantum gravity in a relational manner. Quantum mechanics formulated with a relational time is not exactly unitary and implies a fundamental mechanism for decoherence of quantum states. The mechanism is strong enough to render the black hole information puzzle unobservable.

Rodolfo Gambini; Rafael Porto; Jorge Pullin

2005-01-09T23:59:59.000Z

211

Schrodinger-like (Dilaton-)Gravity  

E-Print Network (OSTI)

We investigate possibilities for the Schrodinger-like gravity with the dynamical critical exponent z=2, where the action only contains the first-order time derivative. The Horava gravity always admits such a relevant deformation because the full (d+1) dimensional diffeomorphism of the Einstein gravity is replaced by the foliation preserving diffeomorphism. The dynamics is locally trivial or topological for the pure gravity case, but we can construct a dynamical field theory with z=2 dispersion relation by introducing a dilaton degree of freedom. Our model gives birth to a new model for quantum (dilaton-)gravity which may be applied to a membrane quantization.

Nakayama, Yu

2010-01-01T23:59:59.000Z

212

ANNOUNCEMENT OF OPPORTUNITY AIRBORNE RESEARCH & SURVEY FACILITY (ARSF)  

E-Print Network (OSTI)

channel 8-12 microns, 320 spatial pixels. Large-format RC-10 aerial survey camera with images beingANNOUNCEMENT OF OPPORTUNITY AIRBORNE RESEARCH & SURVEY FACILITY (ARSF) http://arsf.nerc.ac.uk 2010 OCTOBER 2009 The Airborne Research & Survey Facility (ARSF) invites direct access applications for UK

213

A general method for calculating co-seismic gravity changes in complex fault systems  

Science Conference Proceedings (OSTI)

A general method for calculating the total, dilatational, and free-air gravity for fault systems with arbitrary geometry, slip motion, and number of fault segments is presented. The technique uses a Green's function approach for a fault buried within ... Keywords: 91.10.-v, 91.10.Kg, 91.10.Op, 91.30.Px, Alaska, California, Fault network, Time-variable gravity

T. J. Hayes; K. F. Tiampo; J. B. Rundle; J. Fernández

2008-11-01T23:59:59.000Z

214

Dark Energy: the equation of state description versus scalar-tensor or modified gravity  

E-Print Network (OSTI)

Dark energy dynamics of the universe can be achieved by equivalent mathematical descriptions taking into account generalized fluid equations of state in General Relativity, scalar-tensor theories or modified F(R) gravity in Einstein or Jordan frames. The corresponding technique transforming equation of state description to scalar-tensor or modified gravity is explicitly presented. We show that such equivalent pictures can be discriminated by matching solutions with data capable of selecting the true physical frame.

S. Capozziello; S. Nojiri; S. D. Odintsov

2005-12-10T23:59:59.000Z

215

Granular physics in low-gravity environments using DEM  

E-Print Network (OSTI)

Granular materials of different sizes are present on the surface of several atmosphere-less Solar System bodies. The phenomena related to granular materials have been studied in the framework of the discipline called Granular Physics; that has been studied experimentally in the laboratory and, in the last decades, by performing numerical simulations. The Discrete Element Method simulates the mechanical behavior of a media formed by a set of particles which interact through their contact points. The difficulty in reproducing vacuum and low-gravity environments makes numerical simulations the most promising technique in the study of granular media under these conditions. In this work, relevant processes in minor bodies of the Solar System are studied using the Discrete Element Method. Results of simulations of size segregation in low-gravity environments in the cases of the asteroids Eros and Itokawa are presented. The segregation of particles with different densities was analysed, in particular, the case of comet P/Hartley 2. The surface shaking in these different gravity environments could produce the ejection of particles from the surface at very low relative velocities. The shaking causing the above processes is due to: impacts, explosions like the release of energy by the liberation of internal stresses or the re accommodation of material. Simulations of the passage of impact-induced seismic waves through a granular medium were also performed. We present several applications of the Discrete Element Methods for the study of the physical evolution of agglomerates of rocks under low-gravity environments.

G. Tancredi; A. Maciel; L. Heredia; P. Richeri; S. Nesmachnow

2011-11-26T23:59:59.000Z

216

Observational signatures of Jordan-Brans-Dicke theories of gravity  

E-Print Network (OSTI)

We analyze the Jordan-Brans-Dicke model (JBD) of gravity, where deviations from General Relativity (GR) are described by a scalar field non-minimally coupled to gravity. The theory is characterized by a constant coupling parameter, $\\omega_{\\rm JBD}$; GR is recovered in the limit $\\omega_{\\rm JBD} \\to \\infty$. In such theories, gravity modifications manifest at early times, so that one cannot rely on the usual approach of looking for inconsistencies in the expansion history and perturbations growth in order to discriminate between JBD and GR. However, we show that a similar technique can be successfully applied to early and late times observables instead. Cosmological parameters inferred extrapolating early-time observations to the present will match those recovered from direct late-time observations only if the correct gravity theory is used. We use the primary CMB, as will be seen by the Planck satellite, as the early-time observable; and forthcoming and planned Supernov{\\ae}, Baryonic Acoustic Oscillations and Weak Lensing experiments as late-time observables. We find that detection of values of $\\omega_{\\rm JBD}$ as large as 500 and 1000 is within reach of the upcoming (2010) and next-generation (2020) experiments, respectively.

Viviana Acquaviva; Licia Verde

2007-09-01T23:59:59.000Z

217

The Dark Gravity model predictions for Gravity Probe B  

E-Print Network (OSTI)

The previous version of this article gave erroneous predictions. The correct uptodate predictions can be found in the section devoted to gravitomagnetism in the living review of the Dark Gravity theory: gr-qc/0610079 The most natural prediction is zero frame dragging and the same geodetic effect as predicted by GR. However, a straightforward extension of the theory could lead to the same frame-dragging as in GR.

Frederic Henry-Couannier

2005-09-05T23:59:59.000Z

218

Architecture and Algorithms for an Airborne Network  

E-Print Network (OSTI)

The U.S. Air Force currently is in the process of developing an Airborne Network (AN) to provide support to its combat aircrafts on a mission. The reliability needed for continuous operation of an AN is difficult to achieve through completely infrastructure-less mobile ad hoc networks. In this paper we first propose an architecture for an AN where airborne networking platforms (ANPs - aircrafts, UAVs and satellites) form the backbone of the AN. In this architecture, the ANPs can be viewed as mobile base stations and the combat aircrafts on a mission as mobile clients. The combat aircrafts on a mission move through a space called air corridor. The goal of the AN design is to form a backbone network with the ANPs with two properties: (i) the backbone network remains connected at all times, even though the topology of the network changes with the movement of the ANPs, and (ii) the entire 3D space of the air corridor is under radio coverage at all times by the continuously moving ANPs. In addition to proposing an...

Sen, Arunabha; Silva, Tiffany; Das, Nibedita; Kundu, Anjan

2010-01-01T23:59:59.000Z

219

Gravity survey of the Cove Fort-Sulphurdale KGRA and the North Mineral Mountains area, Millard and Beaver Counties, Utah. Technical report: Volume 77-4  

DOE Green Energy (OSTI)

During the summers of 1975 and 1976, a gravity survey was conducted in the Cove Fort-Sulphurdale KGRA and north Mineral Mountains area, Millard and Beaver Counties, Utah. The survey consisted of 671 gravity stations covering an area of about 1300 km/sup 2/, and included two orthogonal gravity profiles traversing the area. The gravity data are presented as a terrain-corrected Bouguer gravity anomaly map with a contour interval of 1 mgal and as an isometric three-dimensional gravity anomaly surface. Selected anomaly separation techniques were applied to the hand-digitized gravity data (at 1-km intervals on the Universal Transverse Mercator grid) in both the frequency and space domains, including Fourier decomposition, second vertical derivative, strike-filter, and polynomial fitting analysis, respectively.

Brumbaugh, W.D.; Cook, K.L.

1977-08-01T23:59:59.000Z

220

Category:Geophysical Techniques | Open Energy Information  

Open Energy Info (EERE)

Techniques Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Geophysical Techniques page? For detailed information on Geophysical Techniques as exploration techniques, click here. Category:Geophysical Techniques Add.png Add a new Geophysical Techniques Technique Subcategories This category has the following 4 subcategories, out of 4 total. E [+] Electrical Techniques‎ (2 categories) 5 pages G [×] Gravity Techniques‎ 3 pages M [×] Magnetic Techniques‎ 3 pages S [+] Seismic Techniques‎ (2 categories) 2 pages Pages in category "Geophysical Techniques" The following 5 pages are in this category, out of 5 total. D DC Resistivity Survey (Mise-Á-La-Masse) E Electrical Techniques G Gravity Techniques M Magnetic Techniques

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


221

Quantum Gravity at the LHC  

E-Print Network (OSTI)

It has recently been shown that if there is a large hidden sector in Nature, the scale of quantum gravity could be much lower than traditionally expected. We study the production of massless gravitons at the LHC and compare our results to those obtained in extra dimensional models. The signature in both cases is missing energy plus jets. In case of non observation, the LHC could be used to put the tightest limit to date on the value of the Planck mass.

Xavier Calmet; Priscila de Aquino

2009-06-02T23:59:59.000Z

222

Dark Energy and Dark Gravity  

E-Print Network (OSTI)

Observations provide increasingly strong evidence that the universe is accelerating. This revolutionary advance in cosmological observations confronts theoretical cosmology with a tremendous challenge, which it has so far failed to meet. Explanations of cosmic acceleration within the framework of general relativity are plagued by difficulties. General relativistic models are nearly all based on a dark energy field with fine-tuned, unnatural properties. There is a great variety of models, but all share one feature in common -- an inability to account for the gravitational properties of the vacuum energy. Speculative ideas from string theory may hold some promise, but it is fair to say that no convincing model has yet been proposed. An alternative to dark energy is that gravity itself may behave differently from general relativity on the largest scales, in such a way as to produce acceleration. The alternative approach of modified gravity (or dark gravity) provides a new angle on the problem, but also faces serious difficulties, including in all known cases severe fine-tuning and the problem of explaining why the vacuum energy does not gravitate. The lack of an adequate theoretical framework for the late-time acceleration of the universe represents a deep crisis for theory -- but also an exciting challenge for theorists. It seems likely that an entirely new paradigm is required to resolve this crisis.

Ruth Durrer; Roy Maartens

2007-11-01T23:59:59.000Z

223

Dynamical 3-Space: Emergent Gravity  

E-Print Network (OSTI)

The laws of gravitation devised by Newton, and by Hilbert and Einstein, have failed many experimental and observational tests, namely the bore hole g anomaly, flat rotation curves for spiral galaxies, supermassive black hole mass spectrum, uniformly expanding universe, cosmic filaments, laboratory G measurements, galactic EM bending, precocious galaxy formation,.. The response has been the introduction of the new epicycles: ``dark matter", ``dark energy", and others. To understand gravity we must restart with the experimental discoveries by Galileo, and following a heuristic argument we are led to a uniquely determined theory of a dynamical 3-space. That 3-space exists has been missed from the beginning of physics, although it was 1st directly detected by Michelson and Morley in 1887. Uniquely generalising the quantum theory to include this dynamical 3-space we deduce the response of quantum matter and show that it results in a new account of gravity, and explains the above anomalies and others. The dynamical theory for this 3-space involves G, which determines the dissipation rate of space by matter, and alpha, which experiments and observation reveal to be the fine structure constant. For the 1st time we have a comprehensive account of space and matter and their interaction - gravity.

Reginald T Cahill

2011-02-16T23:59:59.000Z

224

Quantitative room-temperature mineralization of airborne formaldehyde using  

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

Quantitative room-temperature mineralization of airborne formaldehyde using Quantitative room-temperature mineralization of airborne formaldehyde using manganese oxide catalysts Title Quantitative room-temperature mineralization of airborne formaldehyde using manganese oxide catalysts Publication Type Journal Article Year of Publication 2011 Authors Sidheswaran, Meera A., Hugo Destaillats, Douglas P. Sullivan, Joern Larsen, and William J. Fisk Journal Applied Catalysis B - Environmental Issue 107 Pagination 34-41 Date Published 2011 Keywords commercial building ventilation & indoor environmental quality group, commercial building ventilation and indoor environmental quality group, energy analysis and environmental impacts department, indoor environment department, indoor environment group DOI 10.1016/j.apcatb.2011.06.032 Attachment Size

225

Spectral Estimates of Gravity Wave Energy and Momentum Fluxes. Part III: Gravity Wave-Tidal Interactions  

Science Conference Proceedings (OSTI)

An application of the gravity wave parameterization scheme developed in the companion papers by Fritts and VanZandt and Fritts and Lu to the mutual interaction of gravity waves and tidal motions is presented. The results suggest that interaction ...

Wentong Lu; David C. Fritts

1993-11-01T23:59:59.000Z

226

Airborne Process Commercial Scale Demonstration Program  

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

CCPI 2) CCPI 2) contacts Brad tomer Director Office of Major Demonstrations National Energy Technology Laboratory 3610 Collins Ferry Road P.O. Box 880 Morgantown, WV 26507-0880 304-285-4692 brad.tomer@netl.doe.gov PaRtIcIPant Mustang Clean Energy, LLC, a subsidiary of Peabody Energy St. Louis, MO. Airborne Process(tm) commerciAl scAle DemonstrAtion ProgrAm (withDrAwn Prior to AwArD) Project Description Mustang Clean Energy will design, construct, and operate a full scale sodium-based multi-pollutant scrubber in conjunction with a revenue-generating fertilizer by-product processing plant at Mustang Energy Company, LLC's Mustang Generating Station. Both Mustang Clean Energy and Mustang Energy Company are subsidiaries of Peabody Energy, the world's largest coal company. The 300 MW (net) station will

227

Born-Infeld gravity in three dimensions  

Science Conference Proceedings (OSTI)

In this paper we explore different aspects of three dimensional Born-Infeld as well as Born-Infeld-Chern-Simons gravity. We show that the models have anti-de Sitter and anti-de Sitter wave vacuum solutions. Moreover, we observe that although Born-Infeld-Chern-Simons gravity admits a logarithmic solution, Born-Infeld gravity does not, though it has a limiting logarithmic solution as we approach the critical point.

Alishahiha, Mohsen [School of physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Naseh, Ali [School of physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of); Soltanpanahi, Hesam [School of physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); School of Physics and Centre for Theoretical Physics, University of the Witwatersrand, WITS 2050 Johannesburg (South Africa)

2010-07-15T23:59:59.000Z

228

Static solutions for fourth order gravity  

SciTech Connect

The Lichnerowicz and Israel theorems are extended to higher order theories of gravity. In particular it is shown that Schwarzschild is the unique spherically symmetric, static, asymptotically flat, black-hole solution, provided the spatial curvature is less than the quantum gravity scale outside the horizon. It is then shown that in the presence of matter (satisfying certain positivity requirements), the only static and asymptotically flat solutions of general relativity that are also solutions of higher order gravity are the vacuum solutions.

Nelson, William [Institute of Gravitation and the Cosmos, Penn State University, State College, Pennsylvania 16801 (United States)

2010-11-15T23:59:59.000Z

229

Quantum Gravity: Has Spacetime Quantum Properties?  

E-Print Network (OSTI)

The incompatibility between GR and QM is generally seen as a sufficient motivation for the development of a theory of Quantum Gravity. If - so a typical argumentation - QM gives a universally valid basis for the description of all natural systems, then the gravitational field should have quantum properties. Together with the arguments against semi-classical theories of gravity, this leads to a strategy which takes a quantization of GR as the natural avenue to Quantum Gravity. And a quantization of the gravitational field would in some sense correspond to a quantization of geometry. Spacetime would have quantum properties. But, this strategy will only be successful, if gravity is a fundamental interaction. - What, if gravity is instead an intrinsically classical phenomenon? Then, if QM is nevertheless fundamentally valid, gravity can not be a fundamental interaction. An intrinsically classical gravity in a quantum world would have to be an emergent, induced or residual, macroscopic effect, caused by other interactions. The gravitational field (as well as spacetime) would not have any quantum properties. A quantization of GR would lead to artifacts without any relation to nature. The serious problems of all approaches to Quantum Gravity that start from a direct quantization of GR or try to capture the quantum properties of gravity in form of a 'graviton' dynamics - together with the, meanwhile, rich spectrum of approaches to an emergent gravity and/or spacetime - make this latter option more and more interesting for the development of a theory of Quantum Gravity. The most advanced emergent gravity (and spacetime) scenarios are of an information-theoretical, quantum-computational type.

Reiner Hedrich

2009-02-02T23:59:59.000Z

230

Ground Gravity Survey At Lightning Dock Area (Cunniff & Bowers, 2005) |  

Open Energy Info (EERE)

Ground Gravity Survey At Lightning Dock Area (Cunniff Ground Gravity Survey At Lightning Dock Area (Cunniff & Bowers, 2005) Exploration Activity Details Location Lightning Dock Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes Two separate gravity surveys were conducted by LDG as part of this GRED Cooperative Agreement. The first survey was conducted in April 2001 and consisted of 77 stations in the north half of Section 7 and south half of Section 6, both sections being in Township 25 South, Range 19 West. A second and much larger survey was conducted in October 2001. This survey consisted of 227 new stations in nine linear traverses that covered more than one hundred (100) square kilometers centered on the known resource area in Section 7 (figure 3).

231

Ground Gravity Survey At Rio Grande Rift Region (Aiken & Ander, 1981) |  

Open Energy Info (EERE)

Rio Grande Rift Region (Aiken & Ander, 1981) Rio Grande Rift Region (Aiken & Ander, 1981) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Rio Grande Rift Region (Aiken & Ander, 1981) Exploration Activity Details Location Rio Grande Rift Geothermal Region Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown References Carlos L.V. Aiken, Mark E. Ander (1981) A Regional Strategy For Geothermal Exploration With Emphasis On Gravity And Magnetotellurics Retrieved from "http://en.openei.org/w/index.php?title=Ground_Gravity_Survey_At_Rio_Grande_Rift_Region_(Aiken_%26_Ander,_1981)&oldid=401473" Category: Exploration Activities What links here Related changes Special pages Printable version

232

Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et Al., 2002) |  

Open Energy Info (EERE)

Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et Al., 2002) Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2002) Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes The project at Cove Fort/Sulphurdale in Utah, T26S R6/7W, is concerned with locating and drilling a 900-meter well to explore the western extension of the Cove Fort-Sulphurdale geothermal area. The geophysical exploration consisted of resistivity, ground magnetic, and microgravity surveys that were made to site the well in an optimum location. References N. R. Warpinski, A. R. Sattlerl, D. A. Sanchez (2002) Geothermal

233

Ground Gravity Survey At Valles Caldera - Sulphur Springs Area (Wilt &  

Open Energy Info (EERE)

Valles Caldera - Sulphur Springs Area (Wilt & Valles Caldera - Sulphur Springs Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Valles Caldera - Sulphur Springs Area (Wilt & Haar, 1986) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting gravity observations along profiles A--A' and B--B' (Talwani et al., 1959). Densities of 2.12, 2.40, and 2.65 g/cm a were used for modeling the near-surface caldera fill, the underlying volcanics, and the basement sections, respectively (Fig. 8). Although correlation with

234

Ground Gravity Survey At Truckhaven Area (Warpinski, Et Al., 2004) | Open  

Open Energy Info (EERE)

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

235

Ground Gravity Survey At Kilauea East Rift Area (Thomas, 1986) | Open  

Open Energy Info (EERE)

Ground Gravity Survey At Kilauea East Rift Area Ground Gravity Survey At Kilauea East Rift Area (Thomas, 1986) Exploration Activity Details Location Kilauea East Rift Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes This model was later expanded through the examination of detailed and regional gravity data (Krivoy and Eaton, 1961) and regional aeromagnetic data (Malahoff and Woollard, 1966) to a three-dimensional map of the rift zone (Furumoto, 1978b). This model projected a dike complex (presumably at high temperatures) which has a width of approximately 20 km near the summit of Kilauea that narrows to approximately 12 km at the lower quarter of the subaerial portion of the rift (Fig. 52). References Donald M. Thomas (1 January 1986) Geothermal Resources Assessment In

236

Detailed gravity and aeromagnetic surveys in the Black Rock Desert Area, Utah. Topical report  

DOE Green Energy (OSTI)

Aeromagnetic and gravity surveys were conducted during 1978 in the Black Rock Desert, Utah over an area of about 2400 km/sup 2/ between the north-trending Pavant and Cricket Mountains. The surveys assisted in evaluating the geothermal resources in the Meadow-Hatton Known Geothermal Resource Area (KGRA) and vicinity by delineating geophysical characteristics of the subsurface. The gravity measurements from approximately 700 new stations were reduced to complete Bouguer gravity anomaly values with the aid of a computerized terrain-correction program and contoured at an interval of 1 milligal. The aeromagnetic survey was drape flown at an altitude of 305 m (1000 ft) and a total intensity residual aeromagnetic map with a contour interval of 20 gammas was produced. Two gravity and aeromagnetic east-west profiles and one north-south profile were modeled using a simultaneous 2 1/2-dimensional modeling technique to provide a single model satisfying both types of geophysical data.

Serpa, L.F.; Cook, K.L.

1980-01-01T23:59:59.000Z

237

Exposure to airborne asbestos in buildings  

SciTech Connect

The concentration of airborne asbestos in buildings and its implication for the health of building occupants is a major public health issue. A total of 2892 air samples from 315 public, commercial, residential, school, and university buildings has been analyzed by transmission electron microscopy. The buildings that were surveyed were the subject of litigation related to suits alleging the general building occupants were exposed to a potential health hazard as a result of exposure to the presence of asbestos containing materials (ACM). The average concentration of all asbestos structures was 0.02 structures/ml (s/ml) and the average concentration of asbestos greater than or equal to 5 microns long was 0.00013 fibers/ml (f/ml). The concentration of asbestos was higher in schools than in other buildings. In 48% of indoor samples and 75% of outdoor samples, no asbestos fibers were detected. The observed airborne concentration in 74% of the indoor samples and 96% of the outdoor samples is below the Asbestos Hazard Emergency Response Act clearance level of 0.01 s/ml. Finally, using those fibers which could be seen optically, all indoor samples and all outdoor samples are below the Occupational Safety and Health Administration permissible exposure level of 0.1 f/ml for fibers greater than or equal to 5 microns in length. These results provide substantive verification of the findings of the U.S. Environmental Protection Agency public building study which found very low ambient concentrations of asbestos fibers in buildings with ACM, irrespective of the condition of the material in the buildings.

Lee, R.J.; Van Orden, D.R.; Corn, M.; Crump, K.S. (RJ Lee Group, Inc., Monroeville, PA (United States))

1992-08-01T23:59:59.000Z

238

Simultaneous measurement of gravity acceleration and gravity gradient with an atom interferometer  

SciTech Connect

We demonstrate a method to measure the gravitational acceleration with a dual cloud atom interferometer; the use of simultaneous atom interferometers reduces the effect of seismic noise on the gravity measurement. At the same time, the apparatus is capable of accurate measurements of the vertical gravity gradient. The ability to determine the gravity acceleration and gravity gradient simultaneously and with the same instrument opens interesting perspectives in geophysical applications.

Sorrentino, F.; Lien, Y.-H.; Rosi, G.; Tino, G. M. [Dipartimento di Fisica e Astronomia and LENS, Universita di Firenze, INFN Sezione di Firenze, via Sansone 1, I-50019 Sesto Fiorentino (Italy); Bertoldi, A. [Laboratoire Charles Fabry de l'Institut d'Optique, CNRS and Universite Paris-Sud Campus Polytechnique, RD 128, F-91127 Palaiseau cedex (France); Bodart, Q. [Dipartimento di Fisica e Astronomia and LENS, Universita di Firenze, INFN Sezione di Firenze, via Sansone 1, I-50019 Sesto Fiorentino (Italy); European Space Agency, Research and Scientific Support Department, Keplerlaan 1, 2201 AZ Noordwijk (Netherlands); Cacciapuoti, L. [European Space Agency, Research and Scientific Support Department, Keplerlaan 1, 2201 AZ Noordwijk (Netherlands); Angelis, M. de [Istituto di Fisica Applicata 'Nello Carrara' CNR, via Madonna del Piano 10, I-50019 Sesto Fiorentino (Italy); Prevedelli, M. [Dipartimento di Fisica dell'Universita di Bologna, Via Irnerio 46, I-40126, Bologna (Italy)

2012-09-10T23:59:59.000Z

239

Lovelock gravity is equivalent to Einstein gravity coupled to form fields  

E-Print Network (OSTI)

Lovelock gravity is a class of higher-derivative gravitational theories whose linearized equations of motion have no more than two time derivatives. Here, it is shown that any Lovelock theory can be effectively described as Einstein gravity coupled to a p-form gauge field. This extends the known example of an f(R) theory of gravity, which can be described as Einstein gravity coupled to a scalar field.

Brustein, Ram

2012-01-01T23:59:59.000Z

240

Cosmological Acceleration: Dark Energy or Modified Gravity?  

E-Print Network (OSTI)

We review the evidence for recently accelerating cosmological expansion or "dark energy", either a negative pressure constituent in General Relativity (Dark Energy) or modified gravity (Dark Gravity), without any Dark Energy constituent. If constituent Dark Energy does not exist, so that our universe is now dominated by pressure-free matter, Einstein gravity must be modified at low curvature. The vacuum symmetry of any Robertson-Walker universe then characterizes Dark Gravity as low- or high-curvature modifications of Einstein gravity. The dynamics of either kind of "dark energy" cannot be derived from the homogeneous expansion alone, but requires also observing the growth of inhomogeneities. Present and projected observations are all consistent with a small fine tuned cosmological constant, with nearly static Dark Energy, or with gravity modified at cosmological scales. The growth of cosmological fluctuations will potentially distinguish static "dark energy" from dynamic "dark energy" with equation of state $w(z)$ either changing rapidly or tracking the background matter. But to cosmologically distinguish $\\Lambda$CDM from modified gravity will require a weak lensing shear survey more ambitious than any now projected. Dvali-Gabadadze-Porrati modifications of Einstein gravity may also be detected in refined bservations in the solar system or at the intermediate Vainstein scale. Dark Energy's epicyclic character, failure to explain the original Cosmic Coincidence ("Why now?") without fine tuning, inaccessibility to laboratory or solar system tests, along with braneworld theories, now motivate future precision solar system, Vainstein-scale and cosmological-scale studies of Dark Gravity.

Sidney Bludman

2006-05-08T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Gravity Gold Concentration at Newmont Mining  

Science Conference Proceedings (OSTI)

Abstract Scope, The process of gold recovery by gravity concentration is incorporated ... Energy Management Planning, Following the ISO 50001 Draft Standard.

242

Optimising Circuit Design for Gravity Gold Recovery  

Science Conference Proceedings (OSTI)

Abstract Scope, To determine the optimal circuit configuration for gravity gold recovery ... Energy Management Planning, Following the ISO 50001 Draft Standard.

243

Thermophysical Property Measurements Under Reduced Gravity ...  

Science Conference Proceedings (OSTI)

Presentation Title, Thermophysical Property Measurements Under Reduced Gravity Conditions: Evolution and Status of theThermoLab Project. Author(s), H-J

244

Gravity from the extension of spatial diffeomorphisms  

E-Print Network (OSTI)

The possibility of the extension of spatial diffeomorphisms to a larger family of symmetries in a class of classical field theories is studied. The generator of the additional local symmetry contains a quadratic kinetic term and a potential term which can be a general (not necessarily local) functional of the metric. From the perspective of the foundation of Einstein's gravity our results are positive: The extended constraint algebra is either that of Einstein's gravity, or ultralocal gravity. If our goal is a simple modification of Einstein's gravity that for example makes it perturbatively renormalizable, as has recently been suggested, then our results show that there is no such theory within this class.

Szilard Farkas; Emil J. Martinec

2010-02-24T23:59:59.000Z

245

Palatini formulation of L(R) gravity  

E-Print Network (OSTI)

We review the Palatini formulation of the higher-derivative gravity of the $L(R)$ form and its applications in cosmology.

Peng Wang; Xin-He Meng

2004-06-21T23:59:59.000Z

246

The Source of Airborne Lead: Recycling Pb-Contaminated Soils  

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

The Source of Airborne Lead: Recycling The Source of Airborne Lead: Recycling Pb-Contaminated Soils Starting in the 1970s, federal regulatory control and eventual elimination of lead-based "anti-knock" additives in gasoline decreased the level of airborne Pb in the USA by two orders-of-magnitude [1]. Blood lead levels of the USA figure 1 Figure 1. The good, the bad, and the ugly. Ambient airborne particulate matter captured on filters of woven silica fiber (large strips) and TeflonTM (round). Clean fiber filter at bottom for comparison. Take a deep breath? population decreased correspondingly [2,3]. Despite this dramatic improvement in both exposure risk and body burden of Pb, the sources and health threat of the low levels of lead in our "unleaded" air remain topics

247

Simulator Evaluation of Airborne Information for Lateral Spacing (AILS) Concept  

Science Conference Proceedings (OSTI)

The Airborne Information for Lateral Spacing (AILS) concept is designed to support independent parallel approach operations to runways spaced as close as 2500 ft. This report describes the AILS operational concept and the results of a ground-based flight ...

Abbott Terence S.; Elliott Dawn M.

2001-03-01T23:59:59.000Z

248

Accurate Airborne Surface Temperature Measurements with Chopper-stabilized Radiometers  

Science Conference Proceedings (OSTI)

The accuracy of chopper-stabilized radiometers for the meteorological measurement of surface temperatures was investigated during a series of airborne trails, including tests at high altitude using a pressurized aircraft. The significant finding ...

Dieter Lorenz

1991-06-01T23:59:59.000Z

249

Calibrations and performance of the airborne Cloud Extinction Probe  

Science Conference Proceedings (OSTI)

A new airborne instrument that measures extinction coefficient ? in clouds and precipitation has been designed by Environment Canada. The Cloud Extinction Probe (CEP) utilizes the transmissiometric method which is based on direct measurement of ...

Alexei Korolev; Alex Shashkov; Howard Barker

250

Airborne Cloud-Physics Projects From 1974 Through 1984  

Science Conference Proceedings (OSTI)

Most of the principal airborne cloud-physics projects during the ten-year period 1974-1984 are documented to provide selected information on the type and quantity of microphysical data that have beencollected. The emphasis is on measurements ...

Richard K. Jeck

1986-12-01T23:59:59.000Z

251

Human Occupancy as a Source of Indoor Airborne Bacteria  

E-Print Network (OSTI)

Exposure to specific airborne bacteria indoors is linked to infectious and noninfectious adverse health outcomes. However, the sources and origins of bacteria suspended in indoor air are not well understood. This study ...

Hospodsky, Denina

252

Feasibility Test of an Airborne Pulse-Doppler Meteorological Radar  

Science Conference Proceedings (OSTI)

A vertically scanning, airborne, pulse-Doppler radar is described. Data processing methods to yield pseudo-dual-Doppler horizontal winds are presented. Results of an intercomparison with a ground-based dual-Doppler network are presented and ...

David P. Jorgensen; Peter H. Hildebrand; Charles L. Frush

1983-05-01T23:59:59.000Z

253

Pre-EUCREX Intercomparison of Airborne Humidity Measuring Instruments  

Science Conference Proceedings (OSTI)

During the pre-EUCREX (European Cloud and Radiation Experiment) intercomparison of airborne instrumentation in January 1992, nine hygrometers mounted on three different aircraft were compared. Although the different instruments are based on ...

J. Ström; R. Busen; M. Quante; B. Guillemet; P. R. A. Brown; J. Heintzenberg

1994-10-01T23:59:59.000Z

254

Airborne Doppler Lidar Observations of Convective Phenomena in Oklahoma  

Science Conference Proceedings (OSTI)

On 30 June 1981, the wind fields around a variety of convective clouds, ranging from large thunderstorm complexes to isolated cumulus congestus, were observed in Oklahoma using an airborne Doppler lidar operated by the National Aeronautics and ...

Eugene W. McCaul Jr.; Howard B. Bluestein; Richard J. Doviak

1987-09-01T23:59:59.000Z

255

The NCAR Airborne Infrared Lidar System: Status and Applications  

Science Conference Proceedings (OSTI)

The National Center for Atmospheric Research Airborne Infrared Lidar System is being developed for Doppler wind measurements using heterodyne detection. Its design is based on a pulsed CO2 laser transmitter and a single continuous-wave CO2 laser ...

R. L. Schwiesow; M. P. Spowart

1996-02-01T23:59:59.000Z

256

Universality in Pure Gravity Mediation  

E-Print Network (OSTI)

If low energy supersymmetry is realized in nature, the apparent discovery of a Higgs boson with mass around 125 GeV points to a supersymmetric mass spectrum in the TeV or multi-TeV range. Multi-TeV scalar masses are a necessary component of supersymmetric models with pure gravity mediation or in any model with strong moduli stabilization. Here, we show that full scalar mass universality remains viable as long as the ratio of Higgs vevs, tan beta is relatively small (\\lesssim 2.5). We discuss in detail the low energy (observable) consequences of these models.

Jason L. Evans; Masahiro Ibe; Keith A. Olive; Tsutomu T. Yanagida

2013-02-21T23:59:59.000Z

257

Quantum Geometry and Quantum Gravity  

E-Print Network (OSTI)

The purpose of this contribution is to give an introduction to quantum geometry and loop quantum gravity for a wide audience of both physicists and mathematicians. From a physical point of view the emphasis will be on conceptual issues concerning the relationship of the formalism with other more traditional approaches inspired in the treatment of the fundamental interactions in the standard model. Mathematically I will pay special attention to functional analytic issues, the construction of the relevant Hilbert spaces and the definition and properties of geometric operators: areas and volumes.

J. Fernando Barbero G.

2008-04-23T23:59:59.000Z

258

Gravity monitoring of CO2 movement during sequestration: Model studies  

E-Print Network (OSTI)

right. Figure 14: Surface gravity response (?Gal) for theAbsolute and relative gravity integration for high precision2003, Seafloor Micro-gravity Survey of the Sleipner CO 2

Gasperikova, E.

2008-01-01T23:59:59.000Z

259

The Opening of the Tasman Sea: A Gravity Anomaly Animation  

Science Conference Proceedings (OSTI)

The first plate tectonic gravity anomaly grid animation using data from the Tasman Sea is presented. In this animation the tectonic elements are represented by their respective gravity fields, based on recent marine-satellite-derived gravity ...

C. Gaina; R. D. Müller; W. R. Roest; P. Symonds

1998-01-01T23:59:59.000Z

260

Gravity  

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

das Farb-Kraftfeld, das entsteht, wenn sich das b Quark vom b Antiquark trennt, ignoriert. Diese Energie wandelt sich in ein weiteres Quark-Antiquark Paar um; was zur Emission...

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Gravity  

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

wissen zwar, wie man Gravitationskrfte berechnet, aber wir wissen nicht, wie man Gravitation in das mathematische Gebude der Quantentheorie des Standardmodells einbauen kann....

262

Gravity  

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

Gravedad Avanzar Volver Principal ESTOY PERDIDO La fuerza gravitacional es quizs la fuerza ms familiar para nosotros, pero no est includa en el Modelo Standard, porque...

263

Gravity in Complex Hermitian Space-Time  

E-Print Network (OSTI)

A generalized theory unifying gravity with electromagnetism was proposed by Einstein in 1945. He considered a Hermitian metric on a real space-time. In this work we review Einstein's idea and generalize it further to consider gravity in a complex Hermitian space-time.

Ali H. Chamseddine

2006-10-09T23:59:59.000Z

264

Scale-Free Growing Networks and Gravity  

E-Print Network (OSTI)

We propose a possible relation between complex networks and gravity. Our guide in our proposal is the power-law distribution of the node degree in network theory and the information approach to gravity. The established bridge may allow us to carry geometric mathematical structures, which are considered in gravitational theories, to probabilistic aspects studied in the framework of complex networks and vice versa.

J. A. Nieto

2011-12-08T23:59:59.000Z

265

Ground Gravity Survey At Valles Caldera - Sulphur Springs Area...  

Open Energy Info (EERE)

Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting...

266

Ground Gravity Survey At Valles Caldera - Redondo Area (Wilt...  

Open Energy Info (EERE)

Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting...

267

Mechanical Properties of Counter-gravity Cast IN718  

Science Conference Proceedings (OSTI)

Key Words: Counter-gravity, investment casting, superalloys, IN718, inert ... using the Counter-gravity Low-pressure Inert-atmosphere (CLI) investment casting ...

268

Ground Gravity Survey At Mcgee Mountain Area (DOE GTP) | Open...  

Open Energy Info (EERE)

Ground Gravity Survey At Mcgee Mountain Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Mcgee Mountain...

269

Definition: Ground Gravity Survey | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Ground Gravity Survey Jump to: navigation, search Dictionary.png Ground Gravity Survey The ground gravitational method is the study of the distribution of mass in the subsurface with the observation point at the earth's surface.[1] View on Wikipedia Wikipedia Definition A gravity anomaly is the difference between the observed acceleration of a planet's gravity and a value predicted from a model. A location with a positive anomaly exhibits more gravity than predicted, while a negative anomaly exhibits a lower value than predicted. References ↑ http://www.amazon.com/Geophysical-Field-Theory-Three-Volume-Gravitational/dp/0124020410 Ret Like Like You like this.Sign Up to see what your friends like.

270

Rainbow gravity and scale-invariant fluctuations  

E-Print Network (OSTI)

We re-examine a recently proposed scenario where the deformed dispersion relations associated with a flow of the spectral dimension to a UV value of 2 leads to a scale-invariant spectrum of cosmological fluctuations, without the need for inflation. In that scenario Einstein gravity was assumed. The theory displays a wavelength-dependent speed of light but by transforming to a suitable "rainbow frame" this feature can be removed, at the expense of modifying gravity. We find that the ensuing rainbow gravity theory is such that gravity switches off at high energy (or at least leads to a universal conformal coupling). This explains why the fluctuations are scale-invariant on all scales: there is no horizon scale as such. For dispersion relations that do not lead to exact scale invariance we find instead esoteric inflation in the rainbow frame. We argue that these results shed light on the behaviour of gravity under the phenomenon of dimensional reduction.

Giovanni Amelino-Camelia; Michele Arzano; Giulia Gubitosi; Joao Magueijo

2013-07-02T23:59:59.000Z

271

A new approach to quantum gravity  

E-Print Network (OSTI)

A new idea of quantum gravity is developed based on Gravitational Complementary Principle. This principle states that gravity has dual complement features: The quantum and classical aspects of gravity are complement and absolutely separated by the planck length into planckian and over-planckian domains, respectively. The classical Einstein equations are correct at the fundamental level at over-planckian domain and general relativity is not a low energy limit of a more fundamental theory. The quantum gravity is totally confined to the planckian domain with a new kind of ultra-short range interaction, mediated by massive (Planck mass) particles, through the virtual microscopic wormholes of the Planck scale with action ¯h. There is no room for gravitons or extra dimensions in ?e-mail:f.darabi@azaruniv.edu 1this scenario. It is shown that the hierarchy problem can solve the cosmological constant problem via this new quantum gravity. 2 1

F. Darabi

2008-01-01T23:59:59.000Z

272

Solar System constraints to nonminimally coupled gravity  

E-Print Network (OSTI)

We extend the analysis of Chiba, Smith and Erickcek \\cite{CSE} of Solar System constraints on $f(R)$ gravity to a class of nonminimally coupled (NMC) theories of gravity. These generalize $f(R)$ theories by replacing the action functional of General Relativity (GR) with a more general form involving two functions $f^1(R)$ and $f^2(R)$ of the Ricci scalar curvature $R$. While the function $f^1(R)$ is a nonlinear term in the action, analogous to $f(R)$ gravity, the function $f^2(R)$ yields a NMC between the matter Lagrangian density $\\LL_m$ and the scalar curvature. The developed method allows for obtaining constraints on the admissible classes of functions $f^1(R)$ and $f^2(R)$, by requiring that predictions of NMC gravity are compatible with Solar System tests of gravity. We apply this method to a NMC model which accounts for the observed accelerated expansion of the Universe.

Orfeu Bertolami; Riccardo March; Jorge Páramos

2013-06-05T23:59:59.000Z

273

ARM Airborne Continuous carbon dioxide measurements  

SciTech Connect

The heart of the AOS CO2 Airborne Rack Mounted Analyzer System is the AOS Manifold. The AOS Manifold is a nickel coated aluminum analyzer and gas processor designed around two identical nickel-plated gas cells, one for reference gas and one for sample gas. The sample and reference cells are uniquely designed to provide optimal flushing efficiency. These cells are situated between a black-body radiation source and a photo-diode detection system. The AOS manifold also houses flow meters, pressure sensors and control valves. The exhaust from the analyzer flows into a buffer volume which allows for precise pressure control of the analyzer. The final piece of the analyzer is the demodulator board which is used to convert the DC signal generated by the analyzer into an AC response. The resulting output from the demodulator board is an averaged count of CO2 over a specified hertz cycle reported in volts and a corresponding temperature reading. The system computer is responsible for the input of commands and therefore works to control the unit functions such as flow rate, pressure, and valve control.The remainder of the system consists of compressors, reference gases, air drier, electrical cables, and the necessary connecting plumbing to provide a dry sample air stream and reference air streams to the AOS manifold.

Sebastien Biraud

2013-03-26T23:59:59.000Z

274

Development of a new airborne humidigraph system.  

Science Conference Proceedings (OSTI)

Modeling and measurements of aerosol properties is complicated by the hygroscopic behavior of the aerosols adding significant uncertainty to our best estimates of the direct effect aerosols exert on the radiative balance of the atmosphere. Airborne measurements of aerosol hygroscopicity are particularly challenging but critically needed. This motivated the development of a newly designed system which can measure the dependence of the aerosol light scattering coefficient (?sp) on relative humidity (RH), known as f(RH), in real-time at a rapid rate (humidity conditioners for simultaneous measurement of the ?sp at three different RHs. The humidity is directly controlled in exchanger cells without significant temperature disturbances and without particle dilution, heating or loss of volatile compounds. The single-wavelength nephelometers are illuminated by LED-based light sources thereby minimizing heating of the sample stream. The flexible design of the RH conditioners, consisting of a number of specially designed exchanger cells (driers or humidifiers), enables us to measure f(RH) under hydration or dehydration conditions (always starting with the aerosol in a known state) with a simple system re-configuration. These exchanger cells have been characterized for losses of particles using latex spheres and laboratory generated ammonium sulfate aerosols. Residence times of 6 - 9 s in the exchangers and subsequent lines is sufficient for most aerosols to attain equilibrium with the new water vapor content. The performance of this system has been assessed aboard DOE’s G-1 research aircraft during test flights over California, Oregon, and Washington.

Pekour, Mikhail S.; Schmid, Beat; Chand, Duli; Hubbe, John M.; Kluzek, Celine D.; Nelson, Danny A.; Tomlinson, Jason M.; Cziczo, Daniel J.

2012-12-06T23:59:59.000Z

275

ARM Airborne Continuous carbon dioxide measurements  

DOE Data Explorer (OSTI)

The heart of the AOS CO2 Airborne Rack Mounted Analyzer System is the AOS Manifold. The AOS Manifold is a nickel coated aluminum analyzer and gas processor designed around two identical nickel-plated gas cells, one for reference gas and one for sample gas. The sample and reference cells are uniquely designed to provide optimal flushing efficiency. These cells are situated between a black-body radiation source and a photo-diode detection system. The AOS manifold also houses flow meters, pressure sensors and control valves. The exhaust from the analyzer flows into a buffer volume which allows for precise pressure control of the analyzer. The final piece of the analyzer is the demodulator board which is used to convert the DC signal generated by the analyzer into an AC response. The resulting output from the demodulator board is an averaged count of CO2 over a specified hertz cycle reported in volts and a corresponding temperature reading. The system computer is responsible for the input of commands and therefore works to control the unit functions such as flow rate, pressure, and valve control.The remainder of the system consists of compressors, reference gases, air drier, electrical cables, and the necessary connecting plumbing to provide a dry sample air stream and reference air streams to the AOS manifold.

Sebastien Biraud

276

Thermodynamics in Modified Gravity Theories  

E-Print Network (OSTI)

We demonstrate that there does exist an equilibrium description of thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density $f(R, \\phi, X)$, where $R$ is the Ricci scalar and $X$ is the kinetic energy of a scalar field $\\phi$. This comes from a suitable definition of an energy momentum tensor of the "dark" component obeying the local energy conservation law in the Jordan frame. It is shown that the equilibrium description in terms of the horizon entropy $S$ is convenient because it takes into account the contribution of the horizon entropy $\\hat{S}$ in non-equilibrium thermodynamics as well as an entropy production term.

Kazuharu Bamba; Chao-Qiang Geng; Shinji Tsujikawa

2011-01-19T23:59:59.000Z

277

Non-Gaussian Stochastic Gravity  

E-Print Network (OSTI)

This paper presents a new, non-Gaussian formulation of stochastic gravity by incorporating the higher moments of the fluctuations of the quantum stress energy tensor for a free quantum scalar field in a consistent way. A scheme is developed for obtaining realizations of these fluctuations in terms of the Wightman function, and the behavior of the fluctuations is investigated. The resulting probability distribution for fluctuations of the energy density in Minkowski spacetime is found to be similar to a shifted Gamma distribution. This distribution features a minimum energy density cutoff at a small negative value, but a sharp peak in the vicinity of this cutoff such that the total probability of observing a negative value is approximately 62%, balanced by correspondingly larger but rarer positive values.

Jason D. Bates

2013-05-16T23:59:59.000Z

278

Nonlinear Fluid Dynamics from Gravity  

E-Print Network (OSTI)

Black branes in AdS5 appear in a four parameter family labeled by their velocity and temperature. Promoting these parameters to Goldstone modes or collective coordinate fields -- arbitrary functions of the coordinates on the boundary of AdS5 -- we use Einstein's equations together with regularity requirements and boundary conditions to determine their dynamics. The resultant equations turn out to be those of boundary fluid dynamics, with specific values for fluid parameters. Our analysis is perturbative in the boundary derivative expansion but is valid for arbitrary amplitudes. Our work may be regarded as a derivation of the nonlinear equations of boundary fluid dynamics from gravity. As a concrete application we find an explicit expression for the expansion of this fluid stress tensor including terms up to second order in the derivative expansion.

Sayantani Bhattacharyya; Veronika E Hubeny; Shiraz Minwalla; Mukund Rangamani

2007-12-14T23:59:59.000Z

279

Exact Solutions in Massive Gravity  

E-Print Network (OSTI)

Massive gravity is a good theoretical laboratory to study modifications of General Relativity. The theory offers a concrete set-up to study models of dark energy, since it admits cosmological self-accelerating solutions in the vacuum, in which the size of the acceleration depends on the graviton mass. Moreover, non-linear gravitational self-interactions, in the proximity of a matter source, manage to mimic the predictions of linearised General Relativity, hence agreeing with solar-system precision measurements. In this article, we review our work in the subject, classifying, on one hand, static solutions, and on the other hand, self-accelerating backgrounds. For what respects static solutions we exhibit black hole configurations, together with other solutions that recover General Relativity near a source via the Vainshtein mechanism. For the self-accelerating solutions we describe a wide class of cosmological backgrounds, including an analysis of their stability.

Gianmassimo Tasinato; Kazuya Koyama; Gustavo Niz

2013-04-02T23:59:59.000Z

280

Emergent Horava gravity in graphene  

E-Print Network (OSTI)

First of all, we reconsider the tight - binding model of monolayer graphene, in which the variations of the hopping parameters are allowed. We demonstrate that the emergent 2D Weitzenbock geometry as well as the emergent U(1) gauge field appear. The emergent gauge field is equal to the linear combination of the components of the zweibein. Therefore, we actually deal with the gauge fixed version of the emergent 2+1 D teleparallel gravity. In particular, we work out the case, when the variations of the hopping parameters are due to the elastic deformations, and relate the elastic deformations with the emergent zweibein. Next, we investigate the tight - binding model with the varying intralayer hopping parameters for the multilayer graphene with the ABC stacking. In this case the emergent 2D Weitzenbock geometry and the emergent U(1) gauge field appear as well, the emergent low energy effective field theory has the anisotropic scaling.

G. E. Volovik; M. A. Zubkov

2013-05-20T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Dark Energy and Modified Gravity  

E-Print Network (OSTI)

Explanations of the late-time cosmic acceleration within the framework of general relativity are plagued by difficulties. General relativistic models are mostly based on a dark energy field with fine-tuned, unnatural properties. There is a great variety of models, but all share one feature in common -- an inability to account for the gravitational properties of the vacuum energy, and a failure to solve the so-called coincidence problem. Two broad alternatives to dark energy have emerged as candidate models: these typically address only the coincidence problem and not the vacuum energy problem. The first is based on general relativity and attempts to describe the acceleration as an effect of inhomogeneity in the universe. If this alternative could be shown to work, then it would provide a dramatic resolution of the coincidence problem; however, a convincing demonstration of viability has not yet emerged. The second alternative is based on infra-red modifications to general relativity, leading to a weakening of gravity on the largest scales and thus to acceleration. Most examples investigated so far are scalar-tensor or brane-world models, and we focus on the simplest candidates of each type: $f(R)$ models and DGP models respectively. Both of these provide a new angle on the problem, but they also face serious difficulties. However, investigation of these models does lead to valuable insights into the properties of gravity and structure formation, and it also leads to new strategies for testing the validity of General Relativity itself on cosmological scales.

Ruth Durrer; Roy Maartens

2008-11-25T23:59:59.000Z

282

A new multidimensional AMR Hydro+Gravity Cosmological code  

E-Print Network (OSTI)

A new cosmological multidimensional hydrodynamic and N-body code based on an Adaptive Mesh Refinement scheme is described and tested. The hydro part is based on modern high-resolution shock-capturing techniques, whereas N-body approach is based on the Particle Mesh method. The code has been specifically designed for cosmological applications. Tests including shocks, strong gradients, and gravity have been considered. A cosmological test based on Santa Barbara cluster is also presented. The usefulness of the code is discussed. In particular, this powerful tool is expected to be appropriate to describe the evolution of the hot gas component located inside asymmetric cosmological structures.

Vicent Quilis

2004-05-20T23:59:59.000Z

283

Emissions of airborne toxics from coal-fired boilers: Mercury  

Science Conference Proceedings (OSTI)

Concerns over emissions of hazardous air Pollutants (air toxics) have emerged as a major environmental issue, and the authority of the US Environmental Protection Agency to regulate such pollutants was greatly expanded through the Clean Air Act Amendments of 1990. Mercury has been singled out for particular attention because of concerns over possible effects of emissions on human health. This report evaluates available published information on the mercury content of coals mined in the United States, on mercury emitted in coal combustion, and on the efficacy of various environmental control technologies for controlling airborne emissions. Anthracite and bituminous coals have the highest mean-mercury concentrations, with subbituminous coals having the lowest. However, all coal types show very significant variations in mercury concentrations. Mercury emissions from coal combustion are not well-characterized, particularly with regard to determination of specific mercury compounds. Variations in emission rates of more than an order of magnitude have been reported for some boiler types. Data on the capture of mercury by environmental control technologies are available primarily for systems with electrostatic precipitators, where removals of approximately 20% to over 50% have been reported. Reported removals for wet flue-gas-desulfurization systems range between 35 and 95%, while spray-dryer/fabric-filter systems have given removals of 75 to 99% on municipal incinerators. In all cases, better data are needed before any definitive judgments can be made. This report briefly reviews several areas of research that may lead to improvements in mercury control for existing flue-gas-clean-up technologies and summarizes the status of techniques for measuring mercury emissions from combustion sources.

Huang, H.S.; Livengood, C.D.; Zaromb, S.

1991-09-01T23:59:59.000Z

284

Generalised Wick Transform in Dimensionally Reduced Gravity  

E-Print Network (OSTI)

In the context of canonical quantum gravity, we study an alternative real quantisation scheme, which is arising by relating simpler Riemannian quantum theory to the more complicated physical Lorentzian theory - the generalised Wick transform. On the symmetry reduced models, homogenous Bianchi cosmology and 2+1 gravity, we investigate its generalised construction principle, demonstrate that the emerging quantum theory is equivalent to the one obtained from standard quantisation and how to obtain physical states in Lorentzian gravity from Wick transforming solutions of Riemannian quantum theory.

B. Hartmann; J. Wisniewski

2003-09-17T23:59:59.000Z

285

Dark Energy from Brane-world Gravity  

E-Print Network (OSTI)

Summary. Recent observations provide strong evidence that the universe is accelerating. This confronts theory with a severe challenge. Explanations of the acceleration within the framework of general relativity are plagued by difficulties. General relativistic models require a “dark energy ” field with effectively negative pressure. An alternative to dark energy is that gravity itself may behave differently from general relativity on the largest scales, in such a way as to produce acceleration. The alternative approach of modified gravity also faces severe difficulties, but does provide a new angle on the problem. This review considers an example of modified gravity, provided by brane-world models that self-accelerate at late times. 1 1

Roy Maartens

2006-01-01T23:59:59.000Z

286

Consistent matter couplings for Plebanski gravity  

SciTech Connect

We develop a scheme for the minimal coupling of all standard types of tensor and spinor field matter to Plebanski gravity. This theory is a geometric reformulation of vacuum general relativity in terms of two-form frames and connection one-forms, and provides a covariant basis for various quantization approaches. Using the spinor formalism we prove the consistency of the newly proposed matter coupling by demonstrating the full equivalence of Plebanski gravity plus matter to Einstein-Cartan gravity. As a by-product we also show the consistency of some previous suggestions for matter actions.

Tennie, Felix; Wohlfarth, Mattias N. R. [Zentrum fuer Mathematische Physik und II. Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)

2010-11-15T23:59:59.000Z

287

Gravity as BF theory plus potential  

E-Print Network (OSTI)

Spin foam models of quantum gravity are based on Plebanski's formulation of general relativity as a constrained BF theory. We give an alternative formulation of gravity as BF theory plus a certain potential term for the B-field. When the potential is taken to be infinitely steep one recovers general relativity. For a generic potential the theory still describes gravity in that it propagates just two graviton polarizations. The arising class of theories is of the type amenable to spin foam quantization methods, and, we argue, may allow one to come to terms with renormalization in the spin foam context.

Kirill Krasnov

2009-07-23T23:59:59.000Z

288

Texas Gulf Coast Refinery District API Gravity (Weighted Average ...  

U.S. Energy Information Administration (EIA)

Texas Gulf Coast Refinery District API Gravity (Weighted Average) of Crude Oil Input to Refineries (Degree)

289

Ph.D.Thesis Binary inversion of gravity  

E-Print Network (OSTI)

Ph.D.Thesis Binary inversion of gravity data for salt imaging Richard A. Krahenbuhl Center for Gravity, Electrical & Magnetic Studies Colorado School of Mines Department of Geophysics Colorado School of gravity data for salt imaging Richard A. Krahenbuhl Center for Gravity, Electrical & Magnetic Studies

290

Texas Gulf Coast Refinery District API Gravity (Weighted ...  

U.S. Energy Information Administration (EIA)

Texas Gulf Coast Refinery District API Gravity (Weighted Average) of Crude Oil Input to Refineries (Degree)

291

Minimum Experimental Standards in the Laboratory Search for Gravity Effects  

Science Conference Proceedings (OSTI)

Peer?reviewed reports of experimental modifications of gravity over rotating superconductors (Podkletnov

H. Reiss; G. Hathaway

2006-01-01T23:59:59.000Z

292

Gravity and General Relativity at KCL D C Robinson  

E-Print Network (OSTI)

Gravity and General Relativity at KCL D C Robinson Mathematics Department King's College London Strand, London WC2R 2LS, UK. February 22, 2011 1 The study of gravity at KCL Research on gravity has been, an approach to New- tonian gravity similar to his field theory formulation of electromagnetism published

Bushnell, Colin J.

293

Gravity Recovery And Climate Experiment Hydrology, Earth Science and Climate  

E-Print Network (OSTI)

GRACE Gravity Recovery And Climate Experiment Hydrology, Earth Science and Climate Ole Baltazar of blood cell Delivers 10-Day / Monthly gravity field From 2002 Onwards Study gravity field changes | side 6 Range responds to Gravity #12;GRACE science results | 28. November 2007 | OA | side 7 Variations

Mosegaard, Klaus

294

Quantitative Measurements of Path-Integrated Rain Rate by an Airborne Microwave Radiometer over the Ocean  

Science Conference Proceedings (OSTI)

Data on the airborne microwave radiometer, which is one of the sensors of the airborne microwave rain-scatterometer/radiometer (AMRS) system, are analyzed to infer path-integrated rain rate measured from topside. The equation of radiative ...

Masaharu Fujita; Ken'ichi Okamoto; Harunobu Masuko; Takeyuki Ojima; Nobuyoshi Fugono

1985-09-01T23:59:59.000Z

295

The Development of an Airborne Infrared Interferometer for Meteorological Sounding Studies  

Science Conference Proceedings (OSTI)

The United Kingdom Meteorological Office (UKMO) has developed an airborne interferometer to act as a simulator for future satellite-based infrared meteorological sounders. The Airborne Research Interferometer Evaluation System (ARIES) consists of ...

S. H. S. Wilson; N. C. Atkinson; J. A. Smith

1999-12-01T23:59:59.000Z

296

Airborne Doppler Lidar Measurements of Valley Flows in Complex Coastal Terrain  

Science Conference Proceedings (OSTI)

Three-dimensional winds obtained with an airborne Doppler lidar are used to investigate the spatial structure of topographically driven flows in complex coastal terrain in Southern California. The airborne Doppler lidar collected four hours of ...

S. F. J. De Wekker; K. S. Godwin; G. D. Emmitt; S. Greco

2012-08-01T23:59:59.000Z

297

Reduced Gravity Education Flight Opportunity for Students at Minority  

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

Reduced Gravity Education Flight Opportunity for Students at Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions March 21, 2013 - 5:21pm Addthis Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions NASA is offering undergraduate students from Minority Serving Institutions an opportunity to test experiments in microgravity aboard NASA's reduced gravity aircraft. This opportunity is a partnership between the Minority University Research and Education Program and NASA's Reduced Gravity Education Flight Program, which gives aspiring explorers a chance to propose, design and fabricate a reduced-gravity experiment. Selected teams will test and evaluate their

298

Reduced Gravity Education Flight Opportunity for Students at Minority  

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

Reduced Gravity Education Flight Opportunity for Students at Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions March 21, 2013 - 5:21pm Addthis Reduced Gravity Education Flight Opportunity for Students at Minority Serving Institutions NASA is offering undergraduate students from Minority Serving Institutions an opportunity to test experiments in microgravity aboard NASA's reduced gravity aircraft. This opportunity is a partnership between the Minority University Research and Education Program and NASA's Reduced Gravity Education Flight Program, which gives aspiring explorers a chance to propose, design and fabricate a reduced-gravity experiment. Selected teams will test and evaluate their

299

AIRBORNE, OPTICAL REMOTE SENSING OF METHANE AND ETHANE FOR NATURAL GAS PIPELINE LEAK DETECTION  

Science Conference Proceedings (OSTI)

Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This six-month technical report summarizes the progress for each of the proposed tasks, discusses project concerns, and outlines near-term goals. Ophir has completed a data survey of two major natural gas pipeline companies on the design requirements for an airborne, optical remote sensor. The results of this survey are disclosed in this report. A substantial amount of time was spent on modeling the expected optical signal at the receiver at different absorption wavelengths, and determining the impact of noise sources such as solar background, signal shot noise, and electronic noise on methane and ethane gas detection. Based upon the signal to noise modeling and industry input, Ophir finalized the design requirements for the airborne sensor, and released the critical sensor light source design requirements to qualified vendors. Responses from the vendors indicated that the light source was not commercially available, and will require a research and development effort to produce. Three vendors have responded positively with proposed design solutions. Ophir has decided to conduct short path optical laboratory experiments to verify the existence of methane and absorption at the specified wavelength, prior to proceeding with the light source selection. Techniques to eliminate common mode noise were also evaluated during the laboratory tests. Finally, Ophir has included a summary of the potential concerns for project success and has established future goals.

Jerry Myers

2003-05-13T23:59:59.000Z

300

ARM - Evaluation Product - Airborne Visible/Infrared Imaging Spectrometer  

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

ProductsAirborne Visible/Infrared Imaging ProductsAirborne Visible/Infrared Imaging Spectrometer (AVIRIS) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) 1997.08.01 - 1997.08.01 Site(s) SGP General Description AVIRIS is an optical sensor that delivers calibrated images of the upwelling spectral radiance in 224 contiguous spectral channels (bands) with wavelengths from 400 to 2500 nanometers. AVIRIS has been flown on two aircraft platforms: a NASA ER-2 jet and the Twin Otter turboprop. The main objective of the AVIRIS project is to identify, measure, and monitor constituents of the Earth's surface and atmosphere based on molecular absorption and particle scattering signatures. Research with

Note: This page contains sample records for the topic "techniques airborne gravity" 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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to obtain the most current and comprehensive results.


301

Gravity Waves in a Horizontal Shear Flow. Part II: Interaction between Gravity Waves and Potential Vorticity Perturbations  

E-Print Network (OSTI)

Gravity Waves in a Horizontal Shear Flow. Part II: Interaction between Gravity Waves and Potential perturbations and propagating internal gravity waves in a horizon- tally sheared zonal flow is investigated. In the strong stratification limit, an initial vorticity perturbation weakly excites two propagating gravity

Farrell, Brian F.

302

Observations of a Mesoscale Ducted Gravity Wave  

Science Conference Proceedings (OSTI)

This paper reports coordinated observations of a mesoscale gravity wave made during the FRONTS 84 field experiment conducted in southwestern France in the summer of 1984. The observations were unique in the sense that all relevant wave ...

F. M. Ralph; V. Venkateswaran; M. Crochet

1993-10-01T23:59:59.000Z

303

Filtering of Gravity Modes in Atmospheric Models  

Science Conference Proceedings (OSTI)

The impact of gravity modes in atmospheric model predictions is assessed quantitatively by comparing integrations with a normal mode initialized primitive equation model and its corresponding pseudogeostrophic form to document some generally ...

F. Baer; J. J. Tribbia

1984-05-01T23:59:59.000Z

304

Stochastic Parameterization of Gravity Wave Stresses  

Science Conference Proceedings (OSTI)

Selective transmission of gravity waves into the upper mesosphere and lower thermosphere leads to the generation of mean flows opposite to those below. This interaction is addressed in the context of a simplified transient, stochastic, ...

Timothy J. Dunkerton

1982-08-01T23:59:59.000Z

305

Generation of Turbulence by Atmospheric Gravity Waves  

Science Conference Proceedings (OSTI)

The standard current criterion for the generation of turbulence by atmospheric gravity waves and for the associated limitation on wave growth is based upon the standard criterion for static instability of the unperturbed atmosphere, namely, that ...

Colin O. Hines

1988-04-01T23:59:59.000Z

306

Effect of Nonlinearity on Atmospheric Gravity Waves  

Science Conference Proceedings (OSTI)

The weakly nonlinear limit of two-dimensional gravity waves in an incompressible, inviscid and stably stratified atmosphere is studied. The three-wave resonant interaction theory indicates an energy cascade from a vertically propagating wave (...

Mostafa M. Ibrahim

1987-02-01T23:59:59.000Z

307

Inertia–Gravity Waves in the Stratosphere  

Science Conference Proceedings (OSTI)

The propagation and refraction of stationary inertia–gravity waves in the winter stratosphere is examined with ray tracing. Due to their smaller vertical group velocity these waves experience more lateral ray movement and horizontal refraction ...

Timothy J. Dunkerton

1984-12-01T23:59:59.000Z

308

Quantum gravity and renormalization: The tensor track  

SciTech Connect

We propose a new program to quantize and renormalize gravity based on recent progress on the analysis of large random tensors. We compare it briefly with other existing approaches.

Rivasseau, Vincent [Laboratoire de Physique Theorique, CNRS UMR 8627 Universite Paris-Sud, 91405 Orsay (France)

2012-06-27T23:59:59.000Z

309

Energy conditions in f(R)-gravity  

E-Print Network (OSTI)

In order to shed some light on the current discussion about f(R)-gravity theories we derive and discuss the bounds imposed by the energy conditions on a general f(R) functional form. The null and strong energy conditions in this framework are derived from the Raychaudhuri's equation along with the requirement that gravity is attractive, whereas the weak and dominant energy conditions are stated from a comparison with the energy conditions that can be obtained in a direct approach via an effective energy-momentum tensor for f(R)-gravity. As a concrete application of the energy conditions to locally homogeneous and isotropic f(R)-cosmology, the recent estimated values of the deceleration and jerk parameters are used to examine the bounds from the weak energy condition on the parameters of two families of f(R)-gravity theories.

Santos, J; Rebouças, M J; Carvalho, F C

2007-01-01T23:59:59.000Z

310

Energy and Hamiltonian in first order gravity  

E-Print Network (OSTI)

In this work the definition of a quasilocal energy for four dimensional first order gravity is developed. Using this an action principle which is adequate for the canonical ensemble is obtained. The microcanonical action principle is obtained as well.

Rodrigo Aros

2005-04-29T23:59:59.000Z

311

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

312

Observationally Verifiable Predictions of Modified Gravity  

Science Conference Proceedings (OSTI)

MOG is a fully relativistic modified theory of gravity based on an action principle. The MOG field equations are exactly solvable numerically in two important cases. In the spherically symmetric

J. W. Moffat; V. T. Toth

2010-01-01T23:59:59.000Z

313

SUSY QM meets 5d Gravity  

E-Print Network (OSTI)

We report hidden quantum mechanical supersymmetry structure in five-dimensional gravity with the Randall-Sundrum background. We show that two N=2 supersymmetries are hidden in the spectrum.

Ohya, Satoshi

2010-01-01T23:59:59.000Z

314

Dynamical Foundations of the Brane Induced Gravity  

E-Print Network (OSTI)

We present a comprehensive formalism to derive precise expressions for the induced gravity of the braneworld, assuming the dynamics of the Dirac-Nambu-Goto type. The quantum fluctuations of the brane at short distances give rise to divergences, which should be cutoff at the scale of the inverse thickness of the brane. It turns out that the induced-metric formula is converted into an Einstein-like equation via the quantum effects. We determine the coefficients of the induced cosmological and gravity terms, as well as those of the terms including the extrinsic curvature and the normal connection gauge field. The latter is the characteristic of the brane induced gravity theory, distinguished from ordinary none-brane induced gravity.

Keiichi Akama; Takashi Hattori

2013-09-12T23:59:59.000Z

315

Shear Excitation of Atmospheric Gravity Waves  

Science Conference Proceedings (OSTI)

Unstable Velocity shears are a Common source of vertically propagating gravity waves in the atmosphere. However, the growth rates of unstable modes predicted by linear theory cannot always amount for their observed importance.

David C. Fritts

1982-09-01T23:59:59.000Z

316

Earthlings : humanity's essential relationship with gravity  

E-Print Network (OSTI)

A realm of serious scientific questions about gravity's role in biology is being researched in labs around the world, from NASA's Dryden Research Laboratories in the Mohave Desert, to Japan's Radioisotope Center at the ...

Vargas Medina, Iris Mónica

2009-01-01T23:59:59.000Z

317

Energy conditions in f(R)-gravity  

E-Print Network (OSTI)

In order to shed some light on the current discussion about f(R)-gravity theories we derive and discuss the bounds imposed by the energy conditions on a general f(R) functional form. The null and strong energy conditions in this framework are derived from the Raychaudhuri's equation along with the requirement that gravity is attractive, whereas the weak and dominant energy conditions are stated from a comparison with the energy conditions that can be obtained in a direct approach via an effective energy-momentum tensor for f(R)-gravity. As a concrete application of the energy conditions to locally homogeneous and isotropic f(R)-cosmology, the recent estimated values of the deceleration and jerk parameters are used to examine the bounds from the weak energy condition on the parameters of two families of f(R)-gravity theories.

J. Santos; J. S. Alcaniz; M. J. Reboucas; F. C. Carvalho

2007-08-02T23:59:59.000Z

318

Internal Gravity Wave Generation and Hydrodynamic Instability  

Science Conference Proceedings (OSTI)

Two mechanisms are proposed whereby internal gravity waves (IGW) may radiate from a linearly unstable region of Boussinesq parallel flow that is characterized in the far field by constant horizontal velocity and Brunt-Väisälä frequency. Through ...

B. R. Sutherland; C. P. Caulfield; W. R. Peltier

1994-11-01T23:59:59.000Z

319

Finite temperature R-squared quantum gravity  

E-Print Network (OSTI)

The quantum gravity path integral's measure can be written as the product of classical backgrounds and quantum fluctuations about each background. After proving that fluctuations about the background do not diffuse in Hilbert space and obey the laws of many-body statistics, their probability distributions, entropy, and expected background are determined. This background obeys expectation-valued Einstein equations and features an entropy-based positive cosmological constant. From the fluctuation probability distributions, a finite temperature, R-squared, quantum gravity path integral is constructed whose action presents an interaction picture of quantum gravity that `moves with' the expected background in Hilbert space. Within this interaction picture of quantum fluctuations about an expected background, the fields required to describe quantum gravity have been transformed into `ordinary' quantum fields propagating on this `rigid' or `fixed' expected background. Back-reaction has been fully accounted for, and the quantum formulation is manifestly background independent.

C. D. Burton

2013-02-07T23:59:59.000Z

320

Evaluation of Meteorological Airborne Doppler Radar. Part II: Triple-Doppler Analyses of Air Motions  

Science Conference Proceedings (OSTI)

This is Part II of a paper dealing with the capabilities and use of airborne Doppler radar to observe motions within storms. Part I deals with dual-Doppler analyses of convective storm structure, using airborne and combinations of airborne and ...

Cynthia K. Mueller; Peter H. Hildebrand

1985-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Towards Gravity-Gauge-Higgs Unification  

E-Print Network (OSTI)

We discuss a possibility to solve the gauge hierarchy problem in the framework of Gravity-Gauge-Higgs Unification scenario. We have calculated 1-loop correction to the mass of the scalar field, which is originated from 55-component of the metric, in five dimensional gravity theory with the bulk scalar field compactified on S^1. It is shown that the quadratic divergences are canceled and the finite mass is generated by explicit diagrammatic calculations and the effective potential calculations.

K. Hasegawa; C. S. Lim; Nobuhito Maru

2004-08-24T23:59:59.000Z

322

Localizing gravity on exotic thick 3-branes  

Science Conference Proceedings (OSTI)

We consider localization of gravity on thick branes with a nontrivial structure. Double walls that generalize the thick Randall-Sundrum solution, and asymmetric walls that arise from a Z{sub 2} symmetric scalar potential, are considered. We present a new asymmetric solution: a thick brane interpolating between two AdS{sub 5} spacetimes with different cosmological constants, which can be derived from a 'fake supergravity' superpotential, and show that it is possible to confine gravity on such branes.

Castillo-Felisola, Oscar [Centro de Fisica Fundamental, Universidad de Los Andes, Merida (Venezuela); International Centre for Theoretical Physics, 34100 Trieste (Italy); Melfo, Alejandra; Pantoja, Nelson; Ramirez, Alba [Centro de Fisica Fundamental, Universidad de Los Andes, Merida (Venezuela)

2004-11-15T23:59:59.000Z

323

Thermodynamics of space quanta models quantum gravity  

E-Print Network (OSTI)

Canonically quantized 3+1 general relativity with the global one dimensionality (1D) conjecture defines the model, which dimensionally reduced and secondary quantized yields the 1D quantum field theory wherein generic one-point correlations create physical scales. This simple quantum gravity model, however, can be developed in a wider sense. In this paper we propose to consider ab initio thermodynamics of space quanta as the quantum gravity phenomenology. The thermodynamics is constructed in the entropic formalism.

L. A. Glinka

2009-06-20T23:59:59.000Z

324

Assessing Hypothetical Gravity Control Propulsion  

E-Print Network (OSTI)

Gauging the benefits of hypothetical gravity control propulsion is difficult, but addressable. The major challenge is that such breakthroughs are still only notional concepts rather than being specific methods from which performance can be rigorously quantified. A recent assessment by Tajmar and Bertolami used the rocket equation to correct naive misconceptions, but a more fundamental analysis requires the use of energy as the basis for comparison. The energy of a rocket is compared to an idealized space drive for the following cases: Earth-to-orbit, interstellar transit, and levitation. The space drive uses 3.6 times less energy for Earth to orbit. For deep space travel, space drive energy scales as the square of delta-v, while rocket energy scales exponentially. This has the effect of rendering a space drive 150-orders-of-magnitude better than a 17,000-sec Specific Impulse rocket for sending a modest 5000 kg probe to traverse 5 light-years in 50 years. Indefinite levitation, which is impossible for a rocket, could conceivably require 62 MJ/kg for a space drive. Assumption sensitivities and further analysis options are listed to guide further inquires.

Marc G. Millis

2006-03-14T23:59:59.000Z

325

Quantum gravity and inventory accumulation  

E-Print Network (OSTI)

We begin by studying inventory accumulation at a LIFO (last-in-first-out) retailer with two products. In the simplest version, the following occur with equal probability at each time step: first product ordered, first product produced, second product ordered, second product produced. The inventory thus evolves as a simple random walk on Z^2. In more interesting versions, a p fraction of customers orders the "freshest available" product regardless of type. We show that the corresponding random walks scale to Brownian motions with diffusion matrices depending on p. We then turn our attention to the critical Fortuin-Kastelyn random planar map model, which gives, for each q>0, a probability measure on random (discretized) two-dimensional surfaces decorated by loops, related to the q-state Potts model. A longstanding open problem is to show that as the discretization gets finer, the surfaces converge in law to a limiting (loop-decorated) random surface. The limit is expected to be a Liouville quantum gravity surface decorated by a conformal loop ensemble, with parameters depending on q. Thanks to a bijection between decorated planar maps and inventory trajectories (closely related to bijections of Bernardi and Mullin), our results about the latter imply convergence of the former in a particular topology. A phase transition occurs at p = 1/2, q=4.

Scott Sheffield

2011-08-10T23:59:59.000Z

326

Testing universal relations of neutron stars with a nonlinear matter-gravity coupling theory  

E-Print Network (OSTI)

Due to our ignorance of the equation of state (EOS) beyond nuclear density, there is still no unique theoretical model for neutron stars (NSs). It is therefore surprising that universal EOS-independent relations connecting different physical quantities of neutron stars can exist. Lau et al. [ApJ, 714, 1234 (2010)] found that the frequency of the $f$-mode oscillation, the mass, and the moment of inertia are connected by universal relations. More recently, Yagi and Yunes [Science, 341, 365 (2013)] discovered the I-Love-Q universal relations among the mass, the moment of inertia, the Love number, and the quadrupole moment. In this paper, we study these universal relations in the Eddington-inspired Born-Infeld (EiBI) gravity. This theory differs from general relativity (GR) significantly only at high densities due to the nonlinear coupling between matter and gravity. It thus provides us an ideal case to test how robust the universal relations of NSs are with respect to the change of the gravity theory. Thanks to the apparent EOS formulation of EiBI gravity developed recently by Delsate and Steinhoff [Phys. Rev. Lett., 109, 021101 (2012)], we are able to study the universal relations in EiBI gravity using the same techniques as those in GR. We find that the universal relations in EiBI gravity are essentially the same as those in GR. Our work shows that, within the currently viable coupling constant, there exists at least one modified gravity theory that is indistinguishable from GR in view of the unexpected universal relations.

Y. -H. Sham; L. -M. Lin; P. T. Leung

2013-12-04T23:59:59.000Z

327

Ground Gravity Survey At Dixie Valley Geothermal Field Area (Blackwell, Et  

Open Energy Info (EERE)

Dixie Valley Geothermal Dixie Valley Geothermal Field Area (Blackwell, Et Al., 2003) Exploration Activity Details Location Dixie Valley Geothermal Field Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes The gravity data are not as site specific as the seismic, but put the major parts of the structure in their proper location and places vital constraints on the possible interpretations of the seismic data. References D. D. Blackwell, K. W. Wisian, M. C. Richards, Mark Leidig, Richard Smith, Jason McKenna (2003) Geothermal Resource Analysis And Structure Of Basin And Range Systems, Especially Dixie Valley Geothermal Field, Nevada Retrieved from "http://en.openei.org/w/index.php?title=Ground_Gravity_Survey_At_Dixie_Valley_Geothermal_Field_Area_(Blackwell,_Et_Al.,_2003)&oldid=388459

328

Ground Gravity Survey At Cove Fort Area (Toksoz, Et Al, 2010) | Open Energy  

Open Energy Info (EERE)

Cove Fort Area (Toksoz, Et Al, 2010) Cove Fort Area (Toksoz, Et Al, 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove Fort Area (Toksoz, Et Al, 2010) Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes We have collected various geophysical data around the geothermal field, including heat flow, gravity, MT, seismic surface wave phase and group velocity maps, seismic body wave travel time data and full seismic waveforms. All of these geophysical data sets have different strengths on characterizing subsurface structures and properties. Combining these data through a coordinated analysis and, when possible, by joint inversion

329

Ground Gravity Survey At Salt Wells Area (Bureau of Land Management, 2009)  

Open Energy Info (EERE)

Salt Wells Area (Bureau of Land Management, 2009) Salt Wells Area (Bureau of Land Management, 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Salt Wells Area (Bureau of Land Management, 2009) Exploration Activity Details Location Salt Wells Geothermal Area Exploration Technique Ground Gravity Survey Activity Date 2008 - 2008 Usefulness not indicated DOE-funding Unknown Exploration Basis Vulcan increased exploration efforts in the summer and fall of 2008, during which time the company drilled two temperature gradient holes (86-15 O on Pad 1 and 17-16 O on Pad 3); conducted seismic, gravity and magnetotelluric surveys; and drilled deep exploration wells at Pads 6 and 8 and binary wells at Pads 1, 2, 4, and 7. Notes Data from these wells is proprietary, and so were unavailable for inclusion

330

Ground Gravity Survey At Long Valley Caldera Area (Laney, 2005) | Open  

Open Energy Info (EERE)

Ground Gravity Survey At Long Valley Caldera Area Ground Gravity Survey At Long Valley Caldera Area (Laney, 2005) Exploration Activity Details Location Long Valley Caldera Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes Localized Strain as a Discriminator of Hidden Geothermal Systems, Vasco and Foxall, 2005. Recent work has focused on (1) collaborating with Alessandro Ferretti to use Permanent Scatterer (PS) InSAR data to infer strain at depth, (2) working with Lane Johnson to develop a dynamic faulting model, and (3) acquiring InSAR data for the region surrounding the Dixie Valley fault zone in collaboration with Dr. William Foxall of LLNL. The InSAR data have been processed and an initial interpretation of the results is ongoing. In particular, we have InSAR stacks for over twenty pairs of

331

Ground Gravity Survey At Lake City Hot Springs Area (Warpinski, Et Al.,  

Open Energy Info (EERE)

Lake City Hot Springs Area (Warpinski, Et Al., Lake City Hot Springs Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Lake City Hot Springs Area (Warpinski, Et Al., 2004) Exploration Activity Details Location Lake City Hot Springs Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes The Lake City site, which is located in far northeastern California, consists of a previously identified geothermal site that has been explored with both geophysics and drilling (Hedel, 1981), but has not been characterized adequately to allow accurate siting or drilling of production wells. Some deep wells, several seismic lines, limited gravity surveys, and geochemical and geological studies have suggested that the geothermal

332

Ground Gravity Survey At Long Valley Caldera Area (Farrar, Et Al., 2003) |  

Open Energy Info (EERE)

Ground Gravity Survey At Long Valley Caldera Area Ground Gravity Survey At Long Valley Caldera Area (Farrar, Et Al., 2003) Exploration Activity Details Location Long Valley Caldera Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes Modeling of both deformation and microgravity data now suggests that (1) there are two inflation sources beneath the caldera, a shallower source 7-10 km beneath the resurgent dome and a deeper source ~15 km beneath the caldera's south moat and (2) the shallower source may contain components of magmatic brine and gas. At shallow depths in the caldera References Christopher D. Farrar, Michael L. Sorey, Evelyn Roeloffs, Devin L. Galloway, James F. Howle, Ronald Jacobson (2003) Inferences On The Hydrothermal System Beneath The Resurgent Dome In Long Valley Caldera,

333

Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski, Et  

Open Energy Info (EERE)

4) 4) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski, Et Al., 2004) Exploration Activity Details Location San Francisco Volcanic Field Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes Northern Arizona University has re-assessed the existing exploration data, geologically mapped the target area, obtained rock samples for age dating and mineral chemistry, performed gravity and magnetic surveys, and integrated these results to identify potential drilling targets and sites. Further work may occur in 2004 or 2005. References N. R. Warpinski, A. R. Sattler, R. Fortuna, D. A. Sanchez, J. Nathwani (2004) Geothermal Resource Exploration And Definition Projects

334

Ground Gravity Survey At Chocolate Mountains Area (Alm, Et Al., 2010) |  

Open Energy Info (EERE)

Chocolate Mountains Area (Alm, Et Al., 2010) Chocolate Mountains Area (Alm, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Chocolate Mountains Area (Alm, Et Al., 2010) Exploration Activity Details Location Chocolate Mountains Area Exploration Technique Ground Gravity Survey Activity Date Usefulness useful DOE-funding Unknown Notes Gravity and ground-based magnetics surveys were conducted during the summer of 2008. This data was acquired to aid in the identification of structures without fair surface expression, obscured by recent deposition. References Steve Alm, S. Bjornstad, M. Lazaro, A. Sabin1, D. Meade, J. Shoffner, W. C. Huang, J. Unruh, M. Strane, H. Ross (2010) Geothermal Energy Resource Investigations, Chocolate Mountains Aerial Gunnery Range,

335

Scalar-tensor representation of $f(R)$ gravity and Birkhoff's theorem  

E-Print Network (OSTI)

Birkhoff's theorem is discussed in the frame of f(R) gravity by using its scalar-tensor representation. Modified gravity has become very popular at recent times as it is able to reproduce the unification of inflation and late-time acceleration with no need of a dark energy component or an inflaton field. Here, another aspect of modified f(R) gravity is studied, specifically the range of validity of Birkhoff's theorem, compared with another alternative to General Relativity, the well known Brans-Dicke theory. As a novelty, here both theories are studied by using a conformal transformation and writing the actions in the Einstein frame, where spherically symmetric solutions are studied by using perturbation techniques. The differences between both theories are analyzed as well as the validity of the theorem within the Jordan and Einstein frames, where interesting results are obtained.

Salvatore Capozziello; Diego Sáez-Gómez

2011-07-05T23:59:59.000Z

336

Real-Time Airborne Particle Analyzer  

Particle analysis is useful for determining chemical compositions in a wide rangeof disciplines, from ascertaining the source of a petroleum sample to duplicating afragrance. The technique is appealing to a broad cross section of analytical ...

337

A STATISTICAL METHOD FOR MEASURING THE GALACTIC POTENTIAL AND TESTING GRAVITY WITH COLD TIDAL STREAMS  

SciTech Connect

We introduce the Minimum Entropy Method, a simple statistical technique for constraining the Milky Way gravitational potential and simultaneously testing different gravity theories directly from 6D phase-space surveys and without adopting dynamical models. We demonstrate that orbital energy distributions that are separable (i.e., independent of position) have an associated entropy that increases under wrong assumptions about the gravitational potential and/or gravity theory. Of known objects, 'cold' tidal streams from low-mass progenitors follow orbital distributions that most nearly satisfy the condition of separability. Although the orbits of tidally stripped stars are perturbed by the progenitor's self-gravity, systematic variations of the energy distribution can be quantified in terms of the cross-entropy of individual tails, giving further sensitivity to theoretical biases in the host potential. The feasibility of using the Minimum Entropy Method to test a wide range of gravity theories is illustrated by evolving restricted N-body models in a Newtonian potential and examining the changes in entropy introduced by Dirac, MONDian, and f(R) gravity modifications.

Penarrubia, Jorge [Instituto de Astrofisica de Andalucia-CSIC, Glorieta de la Astronomia s/n, E-18008 Granada (Spain); Koposov, Sergey E. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Walker, Matthew G., E-mail: jorpega@iaa.es [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

2012-11-20T23:59:59.000Z

338

Finite element modeling of concentrating solar collectors for evauation of gravity loads, bending, and optical characterization.  

DOE Green Energy (OSTI)

Understanding the effects of gravity and wind loads on concentrating solar power (CSP) collectors is critical for performance calculations and developing more accurate alignment procedures and techniques. This paper presents a rigorous finite-element model of a parabolic trough collector that is used to determine the impact of gravity loads on bending and displacements of the mirror facets and support structure. The geometry of the LUZ LS-2 parabolic trough collector was modeled using SolidWorks, and gravity-induced loading and displacements were simulated in SolidWorks Simulation. The model of the trough collector was evaluated in two positions: the 90{sup o} position (mirrors facing upward) and the 0{sup o} position (mirrors facing horizontally). The slope errors of the mirror facet reflective surfaces were found by evaluating simulated angular displacements of node-connected segments along the mirror surface. The ideal (undeformed) shape of the mirror was compared to the shape of the deformed mirror after gravity loading. Also, slope errors were obtained by comparing the deformed shapes between the 90{sup o} and 0{sup o} positions. The slope errors resulting from comparison between the deformed vs. undeformed shape were as high as {approx}2 mrad, depending on the location of the mirror facet on the collector. The slope errors resulting from a change in orientation of the trough from the 90{sup o} position to the 0{sup o} position with gravity loading were as high as {approx}3 mrad, depending on the location of the facet.

Christian, Joshua M.; Ho, Clifford Kuofei

2010-04-01T23:59:59.000Z

339

Methods to determine the size distribution of airborne rhinovirus  

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

Methods to determine the size distribution of airborne rhinovirus Methods to determine the size distribution of airborne rhinovirus Title Methods to determine the size distribution of airborne rhinovirus Publication Type Report Year of Publication 2004 Authors Russell, Marion L., Regine Goth-Goldstein, Michael G. Apte, and William J. Fisk Publisher Lawrence Berkeley National Laboratory Abstract About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Prior research has demonstrated that rhinovirus infections can be transmitted via person-to-person contact and via inhalation of infectious aerosols. Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. To detect airborne HRV, we developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine the assay detection limit of 5 fg of HRV RNA with a linear range over 10,000-fold. This assay was used to quantify the size distribution of an artificially-produced HRV aerosol captured with an Andersen six-stage cascade impactor. In future studies, we hope to use the methods developed here to characterize the size distribution of naturally occurring viral-aerosols

340

Method for measuring the size distribution of airborne rhinovirus  

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

Method for measuring the size distribution of airborne rhinovirus Method for measuring the size distribution of airborne rhinovirus Title Method for measuring the size distribution of airborne rhinovirus Publication Type Conference Proceedings Year of Publication 2002 Authors Russell, Marion L., Regine Goth-Goldstein, Michael G. Apte, and William J. Fisk Conference Name Proceedings of the Indoor Air 2002 Conference, Monterey, CA Volume 1 Pagination 40-45 Publisher Indoor Air 2002, Santa Cruz, CA Abstract About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. We developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay for HRV and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine a detection limit of 5 fg of HRV RNA with a linear range over 1000-fold. To measure the size distribution of HRV aerosols, volunteers with a head cold spent two hours in a ventilated research chamber. Airborne particles from the chamber were collected using an Andersen Six-Stage Cascade Impactor. Each stage of the impactor was analyzed by quantitative RT-PCR for HRV. For the first two volunteers with confirmed HRV infection, but with mild symptoms, we were unable to detect HRV on any stage of the impactor

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Geolocation of Multiple Targets from Airborne Video Without Terrain Data  

Science Conference Proceedings (OSTI)

The task of geolocating targets from airborne video is required for many applications in surveillance, law enforcement, reconnaissance, etc. The usual approaches to target geolocation involve terrain data, single target tracking, gimbal control of camera ... Keywords: Geolocation, IMU-Camera calibration, Tracking, Unmanned aerial vehicle

Kyung Min Han; Guilherme N. Desouza

2011-04-01T23:59:59.000Z

342

Mitigating Geomagnetic Noise in Airborne Magnetic Surveys using GPS  

E-Print Network (OSTI)

Mitigating Geomagnetic Noise in Airborne Magnetic Surveys using GPS S. Skone Department, a limiting factor remains ­ the small-amplitude variations caused by geomagnetic pulsations arising from the correlation of TEC variations with geomagnetic pulsations. Variations in TEC during intervals of Pc 3

Calgary, University of

343

Quality assurance program plan for radionuclide airborne emissions monitoring  

SciTech Connect

This Quality Assurance Program Plan identifies quality assurance program requirements and addresses the various Westinghouse Hanford Company organizations and their particular responsibilities in regards to sample and data handling of radiological airborne emissions. This Quality Assurance Program Plan is prepared in accordance with and to written requirements.

Boom, R.J.

1995-12-01T23:59:59.000Z

344

Quality Assurance Program Plan for radionuclide airborne emissions monitoring  

SciTech Connect

This Quality Assurance Program Plan (QAPP) describes the quality assurance requirements and responsibilities for radioactive airborne emissions measurements activities from regulated stacks are controlled at the Hanford Site. Detailed monitoring requirements apply to stacks exceeding 1% of the standard of 10 mrem annual effective dose equivalent to the maximally exposed individual from operations of the Hanford Site.

Vance, L.M.

1993-07-01T23:59:59.000Z

345

Scattering in Topologically Massive Gravity, Chiral Gravity and the corresponding Anyon-Anyon Potential Energy  

E-Print Network (OSTI)

We compute the tree-level scattering amplitude between two covariantly conserved sources in generic Cosmological Topologically Massive Gravity augmented with a Fierz-Pauli term that has three massive degrees of freedom. We consider the Chiral Gravity limit in the anti-de Sitter space as well as the limit of Flat-Space Chiral Gravity. We show that Chiral Gravity cannot be unitarily deformed with a Fierz-Pauli mass. We calculate the non-relativistic potential energy between two point-like spinning sources. In addition to the expected mass-mass and spin-spin interactions, there are mass-spin interactions due to the presence of the gravitational Chern-Simons term which induces spin for any massive object and turns it to an anyon. We also show that the tree-level scattering is trivial for the Flat-Space Chiral Gravity.

Dengiz, Suat; Tekin, Bayram

2013-01-01T23:59:59.000Z

346

Gravity model studies of Newberry Volcano, Oregon  

SciTech Connect

Newberry, Volcano, a large Quaternary volcano located about 60 km east of the axis of the High Cascades volcanoes in central Oregon, has a coincident positive residual gravity anomaly of about 12 mGals. Model calculations of the gravity anomaly field suggest that the volcano is underlain by an intrusive complex of mafic composition of about 20-km diameter and 2-km thickness, at depths above 4 km below sea level. However, uplifted basement in a northwest trending ridge may form part of the underlying excess mass, thus reducing the volume of the subvolcanic intrusive. A ring dike of mafic composition is inferred to intrude to near-surface levels along the caldera ring fractures, and low-density fill of the caldera floor probably has a thickness of 0.7--0.9 km. The gravity anomaly attributable to the volcano is reduced to the east across a north-northwest trending gravity anomaly gradient through Newberry caldera and suggests that normal, perhaps extensional, faulting has occurred subsequent to caldera formation and may have controlled the location of some late-stage basaltic and rhyolitic eruptions. Significant amounts of felsic intrusive material may exist above the mafic intrusive zone but cannot be resolved by the gravity data.

Gettings, M.E.; Griscom, A.

1988-09-10T23:59:59.000Z

347

GRAVITY DARKENING AND BRIGHTENING IN BINARIES  

SciTech Connect

We apply a von Zeipel gravity darkening model to corotating binaries to obtain a simple, analytical expression for the emergent radiative flux from a tidally distorted primary orbiting a point-mass secondary. We adopt a simple Roche model to determine the envelope structure of the primary, assumed massive and centrally condensed, and use the results to calculate the flux. As for single rotating stars, gravity darkening reduces the flux along the stellar equator of the primary, but, unlike for rotating stars, we find that gravity brightening enhances the flux in a region around the stellar poles. We identify a critical limiting separation beyond which hydrostatic equilibrium no longer is possible, whereby the flux vanishes at the point on the stellar equator of the primary facing the companion. For equal-mass binaries, the total luminosity is reduced by about 13% when this limiting separation is reached.

White, Helen E.; Baumgarte, Thomas W. [Department of Physics and Astronomy, Bowdoin College, Brunswick, ME 04011 (United States); Shapiro, Stuart L. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

2012-06-20T23:59:59.000Z

348

Quantum gravity effects in the Kerr spacetime  

Science Conference Proceedings (OSTI)

We analyze the impact of the leading quantum gravity effects on the properties of black holes with nonzero angular momentum by performing a suitable renormalization group improvement of the classical Kerr metric within quantum Einstein gravity. In particular, we explore the structure of the horizons, the ergosphere, and the static limit surfaces as well as the phase space available for the Penrose process. The positivity properties of the effective vacuum energy-momentum tensor are also discussed and the 'dressing' of the black hole's mass and angular momentum are investigated by computing the corresponding Komar integrals. The pertinent Smarr formula turns out to retain its classical form. As for their thermodynamical properties, a modified first law of black-hole thermodynamics is found to be satisfied by the improved black holes (to second order in the angular momentum); the corresponding Bekenstein-Hawking temperature is not proportional to the surface gravity.

Reuter, M. [Institute of Physics, University of Mainz, Staudingerweg 7, D-55099 Mainz (Germany); Tuiran, E. [Departamento de Fisica, Universidad del Norte, Km 5 via a Puerto Colombia, AA-1569 Barranquilla (Colombia)

2011-02-15T23:59:59.000Z

349

Problems with Mannheim's conformal gravity program  

E-Print Network (OSTI)

We show that Mannheim's conformal gravity program, whose potential has a term proportional to $1/r$ and another term proportional to $r$, does not reduce to Newtonian gravity at short distances, unless one assumes undesirable singularities of the mass density of the proton. Therefore, despite the claim that it successfully explains galaxy rotation curves, unless one assumes the singularities, it seems to be falsified by numerous Cavendish-type experiments performed at laboratories on Earth whose work have not found any deviations from Newton's theory. Moreover, it can be shown that as long as the total mass of the proton is positive, Mannheim's conformal gravity program leads to negative linear potential, which is problematic from the point of view of fitting galaxy rotation curves, which necessarily requires positive linear potential.

Youngsub Yoon

2013-05-01T23:59:59.000Z

350

Energy Distribution in f(R) Gravity  

E-Print Network (OSTI)

The well-known energy problem is discussed in f(R) theory of gravity. We use the generalized Landau-Lifshitz energy-momentum complex in the framework of metric f(R) gravity to evaluate the energy density of plane symmetric solutions for some general f(R) models. In particular, this quantity is found for some popular choices of f(R) models. The constant scalar curvature condition and the stability condition for these models are also discussed. Further, we investigate the energy distribution of cosmic string spacetime.

Sharif, M

2009-01-01T23:59:59.000Z

351

Energy Distribution in f(R) Gravity  

E-Print Network (OSTI)

The well-known energy problem is discussed in f(R) theory of gravity. We use the generalized Landau-Lifshitz energy-momentum complex in the framework of metric f(R) gravity to evaluate the energy density of plane symmetric solutions for some general f(R) models. In particular, this quantity is found for some popular choices of f(R) models. The constant scalar curvature condition and the stability condition for these models are also discussed. Further, we investigate the energy distribution of cosmic string spacetime.

M. Sharif; M. Farasat Shamir

2009-12-18T23:59:59.000Z

352

Gravity waves from vortex dipoles and jets  

E-Print Network (OSTI)

The dissertation first investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Several initially balanced and localized jets induced by vortex dipoles are examined here. Within these dipoles, inertia-gravity waves with intrinsic frequencies 1-2 times the Coriolis parameter are simulated in the jet exit region. The ray tracing analysis reveals strong variation of wave characteristics along ray paths. The dependence of wave amplitude on the Rossby number is examined through experiments in which the two vortices are initially separated by a large distance but subsequently approach each other and form a vortex dipole with an associated amplifying localized jet. The amplitude of stationary gravity waves in the simulations with a 90-km grid spacing increases nearly linearly with the square of the Rossby number but significantly more rapidly when smaller grid spacing is used. To further address the source mechanism of the gravity waves within the vortex dipole, a linear numerical framework is developed based on the framework proposed by Plougonven and Zhang (2007). Using the nonlinearly balanced fields as the basic state and driven by three types of large scale forcing, the vorticity, divergence and thermodynamic forcing, this linear model is utilized to obtain linear wave responses. The wave packets in the linear responses compare reasonably well with the MM5 simulated gravity waves. It is suggested that the vorticity forcing is the leading contribution to both gravity waves in the jet exit region and the ascent/descent feature in the jet core. This linear model is also adopted to study inertia-gravity waves in the vicinity of a baroclinic jet during the life cycle of an idealized baroclinic wave. It is found that the thermodynamic forcing and the vorticity forcing are equally important to the gravity waves in the low stratosphere, but the divergence forcing is again playing a lesser role. Two groups of wave packets are present in the linear responses; their sources appear to locate either near the surface front or near the middle/upper tropospheric jet.

Wang, Shuguang

2008-08-01T23:59:59.000Z

353

Proper Time Flow Equation for Gravity  

E-Print Network (OSTI)

We analyze a proper time renormalization group equation for Quantum Einstein Gravity in the Einstein-Hilbert truncation and compare its predictions to those of the conceptually different exact renormalization group equation of the effective average action. We employ a smooth infrared regulator of a special type which is known to give rise to extremely precise critical exponents in scalar theories. We find perfect consistency between the proper time and the average action renormalization group equations. In particular the proper time equation, too, predicts the existence of a non-Gaussian fixed point as it is necessary for the conjectured nonperturbative renormalizability of Quantum Einstein Gravity.

Bonanno, A

2005-01-01T23:59:59.000Z

354

Linear Stratospheric Gravity Waves above Convective Thermal Forcing  

Science Conference Proceedings (OSTI)

The spectra of linear gravity waves generated by a time-varying tropospheric thermal forcing representing organized convection are compared to the spectra of stratospheric gravity waves generated by organized convection in a fully nonlinear two-...

Rajul E. Pandya; M. Joan Alexander

1999-07-01T23:59:59.000Z

355

Coupling between Gravity Waves and Tropical Convection at Mesoscales  

Science Conference Proceedings (OSTI)

An idealized cloud-system-resolving model simulation is used to examine the coupling between a tropical cloud population and the mesoscale gravity waves that it generates. Spectral analyses of the cloud and gravity wave fields identify a clear ...

Todd P. Lane; Fuqing Zhang

2011-11-01T23:59:59.000Z

356

New Gravity Wave Treatments for GISS Climate Models  

Science Conference Proceedings (OSTI)

Previous versions of GISS climate models have either used formulations of Rayleigh drag to represent unresolved gravity wave interactions with the model-resolved flow or have included a rather complicated treatment of unresolved gravity waves that,...

Marvin A. Geller; Tiehan Zhou; Reto Ruedy; Igor Aleinov; Larissa Nazarenko; Nikolai L. Tausnev; Shan Sun; Maxwell Kelley; Ye Cheng

2011-08-01T23:59:59.000Z

357

Influence of Gravity Waves in the Tropical Upwelling: WACCM Simulations  

Science Conference Proceedings (OSTI)

The annual cycle of tropical upwelling and contributions by planetary and gravity waves are investigated from climatological simulations using the Whole Atmosphere Community Climate Model (WACCM) including three gravity wave drag (GWD) ...

Hye-Yeong Chun; Young-Ha Kim; Hyun-Joo Choi; Jung-Yoon Kim

2011-11-01T23:59:59.000Z

358

Mobility Characterization of Planetary Rover in Reduced Gravity Environment  

Science Conference Proceedings (OSTI)

This paper describes effects of gravity on mobility performance of wheeled rovers for future lunar/planetary exploration missions. A series of model tests of a wheel?terrain system were performed on an aircraft during variable gravity maneuvers

Taizo Kobayashi; Hidetoshi Ochiai; Junya Yamakawa; Shigeru Aoki; Kai Matsui; Akira Miyahara

2008-01-01T23:59:59.000Z

359

Correlation Between Precision Gravity and Subsidence Measurements at Cerro Prieto  

E-Print Network (OSTI)

PRECISION GRAVITY AND SUBSIDENCE MEASUREMENTS AT CERROPRECISION GRAVITY AND SUBSIDENCE MEASUREMENTS AT CERROn d i c a t e s t h a t subsidence took place. Uost of t h e

Zelwer, R.

2010-01-01T23:59:59.000Z

360

An Ultrasimple Spectral Parameterization for Nonorographic Gravity Waves  

Science Conference Proceedings (OSTI)

This paper describes a new computationally efficient, ultrasimple nonorographic spectral gravity wave parameterization model. Its predictions compare favorably, though not perfectly, with a model of gravity wave propagation and breaking that ...

C. D. Warner; M. E. McIntyre

2001-07-01T23:59:59.000Z

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


361

Numerical Study of Gravity Currents in a Channel  

Science Conference Proceedings (OSTI)

A three-dimensional primitive-equation model was used to study gravity currents produced by instantaneous releases of a buoyant fluid in a rectangular channel. Without rotation, the gravity current passes through two distinct phases: an initial ...

Dong-Ping Wang

1985-03-01T23:59:59.000Z

362

Quantum gravity as a group field theory: a sketch  

E-Print Network (OSTI)

We give a very brief introduction to the group field theory approach to quantum gravity, a generalisation of matrix models for 2-dimensional quantum gravity to higher dimension, that has emerged recently from research in spin foam models.

Daniele Oriti

2005-12-07T23:59:59.000Z

363

Linear Spectral Numerical Model for Internal Gravity Wave Propagation  

Science Conference Proceedings (OSTI)

A three-dimensional linear spectral numerical model is proposed to simulate the propagation of internal gravity wave fluctuations in a stably stratified atmosphere. The model is developed to get first-order estimations of gravity wave ...

J. Marty; F. Dalaudier

2010-05-01T23:59:59.000Z

364

An Unusually Strong Gravity Wave over Western Washington  

Science Conference Proceedings (OSTI)

A mesoscale wave disturbance, observed over western Washington State, is studied through local observations and recognized by comparisons with theory as a large-amplitude gravity wave. It is shown that this gravity wave propagated over 200 km in ...

Bruce H. Bauck

1992-06-01T23:59:59.000Z

365

U.S. Percent Total Imported by API Gravity of Crude ...  

U.S. Energy Information Administration (EIA)

Referring Pages: Percentages of Total Imported Crude Oil by API Gravity; Percentages of Total Imported Crude Oil by API Gravity

366

Rapid gravity and gravity gradiometry terrain correction via adaptive quadtree mesh discretization Kristofer Davis, M. Andy Kass, and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado School  

E-Print Network (OSTI)

Rapid gravity and gravity gradiometry terrain correction via adaptive quadtree mesh discretization Kristofer Davis, M. Andy Kass, and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado School of Mines SUMMARY We present a method for modeling the terrain response in gravity and gravity

367

Hypothetical Gravity Control and Implications for Spacecraft Propulsion  

E-Print Network (OSTI)

A scientific analysis of the conditions under which gravity could be controlled and the implications that an hypothetical manipulation of gravity would have for known schemes of space propulsion have been the scope of a recent study carried out for the European Space Agency. The underlying fundamental physical principles of known theories of gravity were analysed and shown that even if gravity could be modified it would bring somewhat modest gains in terms of launching of spacecraft and no breakthrough for space propulsion.

O. Bertolami; M. Tajmar

2002-07-31T23:59:59.000Z

368

Ground Gravity Survey At Blue Mountain Area (Fairbank Engineering...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Blue Mountain Area (Fairbank Engineering, 2006) Exploration Activity...

369

Exact solutions with noncommutative symmetries in Einstein and gauge gravity  

Science Conference Proceedings (OSTI)

We present new classes of exact solutions with noncommutative symmetries constructed in vacuum Einstein gravity (in general

Sergiu I. Vacaru

2005-01-01T23:59:59.000Z

370

Materials Science in Reduced Gravity - Programmaster.org  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... About this Symposium. Meeting, 2013 TMS Annual Meeting & Exhibition. Symposium, Materials Science in Reduced Gravity. Sponsorship ...

371

Gravity and Yang?Mills Fields: Geometrical Approaches  

Science Conference Proceedings (OSTI)

A new geometrical framework for a tetrad?affine formulation of gravity coupled with Yang?Mills fields is proposed.

Roberto Cianci; Stefano Vignolo

2005-01-01T23:59:59.000Z

372

Gravity and ground magnetic surveys of the Thermo Hot Springs KGRA region, Beaver County, Utah  

DOE Green Energy (OSTI)

During the period June to September 1976, gravity and ground magnetic surveys were made in the Thermo Hot Springs KGRA region which is located southwest of the town of Milford, Beaver County, Utah. The regional surveys comprised 273 new gravity and magnetic stations and incorporated 104 previous gravity stations over an area of approximately 620 km{sup 2}. The detailed surveys consisted of 9 east-west profiles in the immediate vicinity of the Thermo Hot Springs KGRA. The gravity data were reduced and are presented as terrain-corrected Bouguer gravity anomaly maps. Terrain corrections were made to a distance of 18.8 km. The regional gravity map shows the following features: (1) a large north-south trend with total relief of 5 mgal extending through the central portion of the study area; (2) an east-west trend with relief of about 7-8 mgal south of the Star Range and Shauntie Hills; (3) a north-south trend with 5 mgal relief east of Blue Mountain; and (4) a broad low of approximately 5 mgal closure southwest of the Shauntie Hills. The trends are probably caused by major faults and the gravity low is probably caused by the southern end of the Wah Wah Valley graben. The detailed gravity map indicates two possible east-west trending faults intersecting a major north-south trending fault in the immediate vicinity of the Thermo Hot Springs. The location of the hot springs appears to be fault controlled. To facilitate interpretation of the gravity data, the following processing and modeling techniques were used: (1) high-pass frequency filtering; (2) polynomial fitting; (3) second derivative; (4) strike filtering; (5) two-dimensional modeling; and (6) three-dimensional modeling. These techniques proved helpful as they more clearly delineated features of interest. The residual maps outlined an elongate north-south graben that extends through the survey area. The strike-filtered maps emphasize the major north-south and east-west faults of the region. Modeling provided reasonable depth estimates for bedrock in the vicinity of the hot springs and supported the structural interpretation for the hot springs area. The magnetic data are presented as total magnetic intensity anomaly maps for both the regional and detailed surveys. The regional map delineates a magnetic high with 600-gammas closure that corresponds to a Tertiary quartz monzonite intrusive in the northeast part of the survey area. An east-west trend with about 300-gammas relief is delineated south of the Shauntie Hills and Star Range and possibly corresponds to an east-west fault. The detailed magnetic map outlines an anomalous low with nearly 100-gammas closure associated with the Thermo Hot Springs. This magnetic low may reflect an alteration zone which is structurally controlled. The following processing and modeling techniques were applied to aid interpretation of the magnetic data: (1) low-pass frequency filtering; (2) strike-filtering; (3) pseudogravity; (4) two and one-half dimensional modeling; and (5) three-dimensional modeling. The low-pass filtering clearly delineates the intrusive and the east-west trend south of the Star Range. The strike-filtering outlines north-south and east-west trends which correlate with faults implied by gravity data. The pseudogravity map indicates that the magnetic and gravity anomalies are not caused by the same bodies. The two and one-half dimensional modeling in the hot springs area provides a possible model for an alteration zone which appears to be structurally controlled. The three-dimensional model of the Tertiary quartz monzonite intrusive indicates a relatively shallow, slightly elongate intrusion that continues to a depth of at least 1 km.

Sawyer, Robert F.; Cook, Kenneth L.

1977-08-01T23:59:59.000Z

373

Gravity Waves in Shear and Implications for Organized Convection  

E-Print Network (OSTI)

Gravity Waves in Shear and Implications for Organized Convection Samuel N. Stechmann Department, Los Angeles, CA 90095­1555. E-mail: stechmann@math.ucla.edu #12;ABSTRACT It is known that gravity, the gravity waves can create a more favorable environment on one side of preexisting convection than the other

Stechmann, Samuel N.

374

Tomo-gravity How to ComputeHow to Compute  

E-Print Network (OSTI)

Tomo-gravity How to ComputeHow to Compute Accurate Traffic Matrices forAccurate Traffic MatricesStanford Shannon LabShannon Lab #12;Tomo-gravity Want to know demands from source to destination ProblemProblem Have link traffic measurements (from SNMP) A B C #12;Tomo-gravity Example App: reliability analysis

Roughan, Matthew

375

Gravity Load Collapse of Building Frames during Earthquakes  

E-Print Network (OSTI)

Gravity Load Collapse of Building Frames during Earthquakes J. P. Moehle, K. J. Elwood, H. Sezen to frames designed primarily for gravity loads. Columns generally were not designed to have strengths capacity of the column. As the axial capacity diminishes, the gravity loads carried by the column must

Sezen, Halil

376

Gravity currents in two-layer stratified media  

E-Print Network (OSTI)

Gravity currents in two-layer stratified media Morris R. Flynn & Alan W.Tan Dept. of Mechanical Engineering, U.Alberta Funding: NSERC #12;· Gravity currents appear over a broad range of time/length scales. (1999), Flynn & Linden (2006),White & Helfrich (2008), Ungarish (2009) Introduction current gravity

Flynn, Morris R.

377

Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow  

E-Print Network (OSTI)

Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow Michael Baumer University Gravity Wave 2 3 Measurements 3 4 Mechanical Hardware: Problems and Solutions 5 5 Results 7 6 Conclusions investigated a free-surface gravity wave bifurcation in the large-separation regime, that is, where

Witten, Thomas A.

378

Gravity waves excited by jets: Propagation versus generation R. Plougonven  

E-Print Network (OSTI)

Gravity waves excited by jets: Propagation versus generation R. Plougonven School of Mathematics September 2005. [1] Atmospheric jets are known to be an important source of inertia-gravity waves, yet mechanisms for the gravity waves, with the underlying assumption that the characteristics of the waves were

Plougonven, Riwal

379

New quantum gravity effect, dark energy, accelerating universe, black hole and experimental scheme using superfluid Helium and atom interferometer  

E-Print Network (OSTI)

Considerable attention has been focused on Verlinde's recent work, claiming that Newton's gravity is not a fundamental force. In a recent work (arXiv:1012.5858), we give further the logic basis and basic clues to derive the Newton's gravity, inertia law and Einstein's weak equivalence principle. In this work, we show that if the gravity is not a fundamental force, in special case, it could be repulsive when quantum wavepacket effect is considered. This quantum gravity effect leads to several physical effects: (1) It is consistent with the universe with accelerating expansion, if the gravity and quantum effect of the fluctuating 'vacuum' (dark energy) is considered. The role of the cosmological constant is naturally interpreted when the gravity and quantum effect of the whole 'vacuum' background is considered. (2) It leads to new idea about black hole information paradox, no-hair theorem and Hawking radiation. (3) With a sphere full of superfluid Helium, we propose a feasible experimental scheme to test our idea with an atom interferometer placed in the sphere. Our calculations show that the accuracy Delta g/g below 10^(-8) could be used to test our idea, which satisfies the present experimental technique of atom interferometer.

Hongwei Xiong

2011-01-03T23:59:59.000Z

380

Effects of Nonlinearity on Convectively Forced Internal Gravity Waves: Application to a Gravity Wave Drag Parameterization  

Science Conference Proceedings (OSTI)

In the present study, the authors propose a way to include a nonlinear forcing effect on the momentum flux spectrum of convectively forced internal gravity waves using a nondimensional numerical model (NDM) in a two-dimensional framework. In NDM, ...

Hye-Yeong Chun; Hyun-Joo Choi; In-Sun Song

2008-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Convective Generation of Gravity Waves in Venus's Atmosphere: Gravity Wave Spectrum and Momentum Transport  

Science Conference Proceedings (OSTI)

The emission of internal gravity waves from a layer of dry convection embedded within a stable atmosphere with static stability and zonal winds varying in height is calculated. This theory is applied to Venus to investigate whether these waves ...

Stephen S. Leroy; Andrew P. Ingersoll

1995-11-01T23:59:59.000Z

382

The Mars Gravity Biosatellite as an innovative partial gravity research platform  

E-Print Network (OSTI)

The Mars Gravity Biosatellite is an unprecedented independent spaceflight platform for gravitational biology research. With a projected first launch after 2010, the low Earth orbit satellite will support a cohort of fifteen ...

Fulford-Jones, Thaddeus R. F

2008-01-01T23:59:59.000Z

383

Improvement of Orographic Gravity Wave Parameterization Using a Mesoscale Gravity Wave Model  

Science Conference Proceedings (OSTI)

Parameterization of gravity waves due to subgrid-scale orography is now included in most existing large-scale models of the atmosphere. Parameterization schemes, however, have so far been evaluated mainly in view of the overall performance of the ...

Young-Joon Kim; Akio Arakawa

1995-06-01T23:59:59.000Z

384

Atmospheric Gravity Waves and Aircraft Turbulence Encounters  

Science Conference Proceedings (OSTI)

We describe aircraft turbulence-atmospheric gravity wave events which occurred during a 2-day period over the Continental Divide. The waves are observed by two microbarograph networks an each side of the divide and last for several hours at a ...

A. J. Bedard Jr.; F. Canavero; F. Einaudi

1986-12-01T23:59:59.000Z

385

High energy scattering in gravity and supergravity  

E-Print Network (OSTI)

We investigate features of perturbative gravity and supergravity by studying scattering in the ultraplanckian limit, and sharpen arguments that the dynamics is governed by long-distance physics. A simple example capturing aspects of the eikonal resummation suggests why short distance phenomena and in particular divergences or nonrenormalizability do not necessarily play a central role in this regime. A more profound problem is apparently unitarity. These considerations can be illustrated by showing that known gravity and supergravity amplitudes have the same long-distance behavior, despite the extra light states of supergravity, and this serves as an important check on long-range dynamics in a context where perturbative amplitudes are finite. We also argue that these considerations have other important implications: they obstruct probing the conjectured phenomenon of asymptotic safety through a physical scattering process, and ultraplanckian scattering exhibiting Regge behavior. These arguments sharpen the need to find a nonperturbative completion of gravity with mechanisms which restore unitarity in the strong gravity regime.

Steven B. Giddings; Maximilian Schmidt-Sommerfeld; Jeppe R. Andersen

2010-05-28T23:59:59.000Z

386

MODIFIED GRAVITY SPINS UP GALACTIC HALOS  

SciTech Connect

We investigate the effect of modified gravity on the specific angular momentum of galactic halos by analyzing the halo catalogs at z = 0 from high-resolution N-body simulations for a f(R) gravity model that meets the solar-system constraint. It is shown that the galactic halos in the f(R) gravity model tend to acquire significantly higher specific angular momentum than those in the standard {Lambda}CDM model. The largest difference in the specific angular momentum distribution between these two models occurs for the case of isolated galactic halos with mass less than 10{sup 11} h {sup -1} M {sub Sun }, which are likely least shielded by the chameleon screening mechanism. As the specific angular momentum of galactic halos is rather insensitive to other cosmological parameters, it can in principle be an independent discriminator of modified gravity. We speculate a possibility of using the relative abundance of low surface brightness galaxies (LSBGs) as a test of general relativity given that the formation of the LSBGs occurs in fast spinning dark halos.

Lee, Jounghun [Astronomy Program, Department of Physics and Astronomy, FPRD, Seoul National University, Seoul 151-747 (Korea, Republic of)] [Astronomy Program, Department of Physics and Astronomy, FPRD, Seoul National University, Seoul 151-747 (Korea, Republic of); Zhao, Gong-Bo [National Astronomy Observatories, Chinese Academy of Science, Beijing 100012 (China)] [National Astronomy Observatories, Chinese Academy of Science, Beijing 100012 (China); Li, Baojiu [Institute of Computational Cosmology, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom)] [Institute of Computational Cosmology, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Koyama, Kazuya, E-mail: jounghun@astro.snu.ac.kr [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom)] [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom)

2013-01-20T23:59:59.000Z

387

Gravity Currents in a Deep Anelastic Atmosphere  

Science Conference Proceedings (OSTI)

This study presents analytic results for steady gravity currents in a channel using the deep anelastic equations. Results are cast in terms of a nondimensional parameter H/H0 that relates the channel depth H to a scale depth H0 (the depth at ...

George H. Bryan; Richard Rotunno

2008-02-01T23:59:59.000Z

388

Gravity Waves, Dynamical Resistance, and Forcing Efficiency  

Science Conference Proceedings (OSTI)

The effect of the dynamical response associated with high-frequency gravity waves on the total energy generated by imposed heating is examined in a 2D linear compressible model. The work performed by waves against a sustained forcing is defined ...

Jeffrey M. Chagnon

2010-06-01T23:59:59.000Z

389

Flavorful hybrid anomaly-gravity mediation  

SciTech Connect

We consider supersymmetric models where anomaly and gravity mediation give comparable contributions to the soft terms and discuss how this can be realized in a five-dimensional brane world. The gaugino mass pattern of anomaly mediation is preserved in such a hybrid setup. The flavorful gravity-mediated contribution cures the tachyonic slepton problem of anomaly mediation. The supersymmetric flavor puzzle is solved by alignment. We explicitly show how a working flavor-tachyon link can be realized with Abelian flavor symmetries and give the characteristic signatures of the framework, including O(1) slepton mass splittings between different generations and between doublets and singlets. This provides opportunities for same flavor dilepton edge measurements with missing energy at the Large Hadron Collider (LHC). Rare lepton decay rates could be close to their current experimental limit. Compared to pure gravity mediation, the hybrid model is advantageous because it features a heavy gravitino which can avoid the cosmological gravitino problem of gravity-mediated models combined with leptogenesis.

Gross, Christian; Hiller, Gudrun [Institut fuer Physik, Technische Universitaet Dortmund, D-44221 Dortmund (Germany)

2011-05-01T23:59:59.000Z

390

Energy definition for quadratic curvature gravities  

E-Print Network (OSTI)

A conserved current for generic quadratic curvature gravitational models is defined, and it is shown that, at the linearized level, it corresponds to the Deser-Tekin charges. An explicit expression for the charge for new massive gravity in three dimensions is given. Some implications of the linearized equations are discussed.

Ahmet Baykal

2012-12-03T23:59:59.000Z

391

Ultrasonic hydrometer. [Specific gravity of electrolyte  

DOE Patents (OSTI)

The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time t between the initial and returning impulses. Considering the distance d between the spaced sonic surfaces and the measured time t, the sonic velocity V is calculated with the equation V = 2d/t. The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between 0 and 40/sup 0/C and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation.

Swoboda, C.A.

1982-03-09T23:59:59.000Z

392

Multiple Gravity-Wave Breaking Levels  

Science Conference Proceedings (OSTI)

It is noted that gravity waves for which |u¯?c| (u¯=mean flow speed, c=wave phase speed) has a sharp minimum in the upper troposphere or lower stratosphere will have decaying amplitudes above this level despite exponentially decreasing mean ...

Richard S. Lindzen

1985-02-01T23:59:59.000Z

393

Cosmological singularities and modified theories of gravity  

Science Conference Proceedings (OSTI)

We consider perturbative modifications of the Friedmann equations in terms of energy density corresponding to modified theories of gravity proposed as an alternative route to comply with the observed accelerated expansion of the universe. Assuming that the present matter content of the universe is a pressureless fluid

Leonardo Fernández?Jambrina; Ruth Lazkoz

2009-01-01T23:59:59.000Z

394

Superadiabatic Excess and Gravity Wave Saturation  

Science Conference Proceedings (OSTI)

Attention is called to a recent calculation of the superadiabatic excess—the ratio of wave amplitude at saturation to wave amplitude at convective instability threshold—caused by a saturated gravity wave. (This excess is also referred to as the ...

J. Weinstock

1988-11-01T23:59:59.000Z

395

Heat Transfer in Superfluids: Effect of Gravity  

E-Print Network (OSTI)

We discuss the influence of an external field on energy transport in superfluid. He-II is not isothermal in presence of Earth gravity; instead, it supports finite temperature gradient given by a Fourier-like equation. We calculate asymptotic behavior of the effective heat resistance in the vicinity of the $\\lambda$-transition.

L. A. Melnikovsky

2004-05-19T23:59:59.000Z

396

Charged Black Holes in New Massive Gravity  

E-Print Network (OSTI)

We construct charged black hole solutions to three-dimensional New Massive Gravity (NMG), by adding electromagnetic Maxwell and Chern-Simons actions. We find charged black holes in the form of warped AdS_3 and "log" solutions in specific critical point. The entropy, mass and angular momentum of these black holes are computed.

Ghodsi, Ahmad

2010-01-01T23:59:59.000Z

397

Nonlinearities in modified gravity cosmology: Signatures of modified gravity in the nonlinear matter power spectrum  

SciTech Connect

A large fraction of cosmological information on dark energy and gravity is encoded in the nonlinear regime. Precision cosmology thus requires precision modeling of nonlinearities in general dark energy and modified gravity models. We modify the Gadget-2 code and run a series of N-body simulations on modified gravity cosmology to study the nonlinearities. The modified gravity model that we investigate in the present paper is characterized by a single parameter {zeta}, which determines the enhancement of particle acceleration with respect to general relativity (GR), given the identical mass distribution ({zeta}=1 in GR). The first nonlinear statistics we investigate is the nonlinear matter power spectrum at k < or approx. 3h/Mpc, which is the relevant range for robust weak lensing power spectrum modeling at l < or approx. 2000. In this study, we focus on the relative difference in the nonlinear power spectra at corresponding redshifts where different gravity models have the same linear power spectra. This particular statistics highlights the imprint of modified gravity in the nonlinear regime and the importance of including the nonlinear regime in testing GR. By design, it is less susceptible to the sample variance and numerical artifacts. We adopt a mass assignment method based on wavelet to improve the power spectrum measurement. We run a series of tests to determine the suitable simulation specifications (particle number, box size, and initial redshift). We find that, the nonlinear power spectra can differ by {approx}30% for 10% deviation from GR (|{zeta}-1|=0.1) where the rms density fluctuations reach 10. This large difference, on one hand, shows the richness of information on gravity in the corresponding scales, and on the other hand, invalidates simple extrapolations of some existing fitting formulae to modified gravity cosmology.

Cui Weiguang; Zhang Pengjie; Yang Xiaohu [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Partner Group of MPA, Nandan Road 80, Shanghai, 200030 (China)

2010-05-15T23:59:59.000Z

398

The quest for solar gravity modes: probing the solar interior  

E-Print Network (OSTI)

The solar gravity modes are the best probes to improve our knowledge on the solar interior, as they spend most of their time in the radiative zone, which represents 98% of the solar mass. Many attempts have been led to observe them using different techniques: either individually, then adding some statistical approach or more recently, globally leading to the detection of the signature of asymptotical properties of these modes. Then, several theoretical works have been done to quantify the effect of detecting g-mode on solar modeling and on the rotation profile. We will give here an update on the g-mode detection. Then, we will study an example of a theoretical work showing how their detection would improve our knowledge on the dynamics of the solar core as well as an application on the detection of the global properties to infer some physical inputs in solar models.

Mathur, S

2009-01-01T23:59:59.000Z

399

Holographic Entanglement Entropy for 4D Conformal Gravity  

E-Print Network (OSTI)

Using the proposal for holographic entanglement entropy in higher derivative gravities, we compute holographic entanglement entropy for the conformal gravity in four dimensions which turns out to be finite. However, if one subtracts the contribution of the four dimensional Gauss-Bonnet term, the corresponding entanglement entropy has a divergent term and indeed restricted to an Einstein solution of the conformal gravity, the resultant entanglement entropy is exactly the same as that in the Einstein gravity. We will also make a comment on the first law of the entanglement thermodynamics for the conformal gravity in four dimensions.

Mohsen Alishahiha; Amin Faraji Astaneh; M. Reza Mohammadi Mozaffar

2013-11-18T23:59:59.000Z

400

On the z=4 Horava-Lifshitz Gravity  

E-Print Network (OSTI)

We consider z=4 Horava-Lifshitz gravity in both 3+1 and 4+1 dimensions. We find black hole solutions in the IR region for a kind of z=4 Horava-Lifshitz gravity which is inherited from the new massive gravity in three dimensions and an analog of the new massive gravity in four dimensions through the quantum inheritance principle. We analyze thermodynamic properties for the black hole solutions for z=4 Horava-Lifshitz gravity. We also write out the Friedmann equation in 3+1 dimensions for cosmological solutions.

Rong-Gen Cai; Yan Liu; Ya-Wen Sun

2009-04-27T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Granular convection and the Brazil nut effect in reduced gravity  

E-Print Network (OSTI)

We present laboratory experiments of a vertically vibrated granular medium consisting of 1 mm diameter glass beads with embedded 8 mm diameter intruder glass beads. The experiments were performed in the laboratory as well as in a parabolic flight under reduced-gravity conditions (on Martian and Lunar gravity levels). We measured the mean rise velocity of the large glass beads and present its dependence on the fill height of the sample containers, the excitation acceleration, and the ambient gravity level. We find that the rise velocity scales in the same manner for all three gravity regimes and roughly linearly with gravity.

Carsten Güttler; Ingo von Borstel; Rainer Schräpler; Jürgen Blum

2013-04-02T23:59:59.000Z

402

Black Holes in Three Dimensional Topological Gravity  

E-Print Network (OSTI)

We investigate the black hole solution to (2+1)-dimensional gravity coupled to topological matter, with a vanishing cosmological constant. We calculate the total energy, angular momentum and entropy of the black hole in this model and compare with results obtained in Einstein gravity. We find that the theory with topological matter reverses the identification of energy and angular momentum with the parameters in the metric, compared with general relativity, and that the entropy is determined by the circumference of the inner rather than the outer horizon. We speculate that this results from the contribution of the topological matter fields to the conserved currents. We also briefly discuss two new possible (2+1)-dimensional black holes.

S. Carlip; J. Gegenberg; R. B. Mann

1994-10-17T23:59:59.000Z

403

A perspective on Quantum Gravity Phenomenology  

E-Print Network (OSTI)

I give a brief overview of some Quantum-Gravity-Phenomenology research lines, focusing on studies of cosmic rays and gamma-ray bursts that concern the fate of Lorentz symmetry in quantum spacetime. I also stress that the most valuable phenomenological analyses should not mix too many conjectured new features of quantum spacetime, and from this perspective it appears that it should be difficult to obtain reliable guidance on the quantum-gravity problem from the analysis of synchrotron radiation from the Crab nebula and from the analysis of phase coherence of light from extragalactic sources. Forthcoming observatories of ultra-high-energy neutrinos should provide several opportunities for clean tests of some simple hypothesis for the short-distance structure of spacetime. In particular, these neutrino studies, and some related cosmic-ray studies, should provide access to the regime $E>\\sqrt{m E_p}$.

Giovanni Amelino-Camelia

2004-02-02T23:59:59.000Z

404

Non-Newtonian gravity in finite nuclei  

E-Print Network (OSTI)

In this talk, we report our recent study of constraining the non-Newtonian gravity at femtometer scale. We incorporate the Yukawa-type non-Newtonian gravitational potential consistently to the Skyrme functional form using the exact treatment for the direct contribution and density-matrix expansion method for the exchange contribution. The effects from the non-Newtonian potential on finite nuclei properties are then studied together with a well-tested Skyrme force. Assuming that the framework without non-Newtonian gravity can explain the binding energies and charge radii of medium to heavy nuclei within 2% error, we set an upper limit for the strength of the non-Newtonian gravitational potential at femtometer scale.

Xu, Jun; Chen, Lie-Wen; Zheng, Hao

2012-01-01T23:59:59.000Z

405

Hydrogen atom in Palatini theories of gravity  

E-Print Network (OSTI)

We study the effects that the gravitational interaction of $f(R)$ theories of gravity in Palatini formalism has on the stationary states of the Hydrogen atom. We show that the role of gravity in this system is very important for lagrangians $f(R)$ with terms that grow at low curvatures, which have been proposed to explain the accelerated expansion rate of the universe. We find that new gravitationally induced terms in the atomic Hamiltonian generate a strong backreaction that is incompatible with the very existence of bound states. In fact, in the 1/R model, Hydrogen disintegrates in less than two hours. The universe that we observe is, therefore, incompatible with that kind of gravitational interaction. Lagrangians with high curvature corrections do not lead to such instabilities.

Gonzalo J. Olmo

2008-02-27T23:59:59.000Z

406

Modified Gravity via Spontaneous Symmetry Breaking  

E-Print Network (OSTI)

We construct effective field theories in which gravity is modified via spontaneous breaking of local Lorentz invariance. This is a gravitational analogue of the Higgs mechanism. These theories possess additional graviton modes and modified dispersion relations. They are manifestly well-behaved in the UV and free of discontinuities of the van Dam-Veltman-Zakharov type, ensuring compatibility with standard tests of gravity. They may have important phenomenological effects on large distance scales, offering an alternative to dark energy. For the case in which the symmetry is broken by a vector field with the wrong sign mass term, we identify four massless graviton modes (all with positive-definite norm for a suitable choice of a parameter) and show the absence of the discontinuity.

B. M. Gripaios

2004-08-17T23:59:59.000Z

407

Holographic Superconductivity with Gauss-Bonnet gravity  

E-Print Network (OSTI)

I review recent work on holographic superconductivity with Einstein-Gauss-Bonnet gravity, and show how the critical temperature of the superconductor depends on both gravitational backreaction and the Gauss-Bonnet parameter, using both analytic and numerical arguments. I also review computations of the conductivity, finding the energy gap, and demonstrating that there is no universal gap ratio, $\\omega_g/T_c$, for these superconductors.

Ruth Gregory

2010-12-07T23:59:59.000Z

408

Gravity controlled anti-reverse rotation device  

DOE Patents (OSTI)

A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.

Dickinson, Robert J. (Shaler Township, Allegheny County, PA); Wetherill, Todd M. (Lower Burrell, PA)

1983-01-01T23:59:59.000Z

409

1 Quantum Gravity and Regge Calculus  

E-Print Network (OSTI)

This is an informal review of the formulation of canonical general relativity and of its implications for quantum gravity; the various versions are compared, both in the continuum and in a discretized approximation suggested by Regge calculus. I also show that the weakness of the link with the geometric content of the theory gives rise to what I think is a serious flaw in the claimed derivation of a discrete structure for space at the quantum level. 1.

Giorgio Immirzi A

1997-01-01T23:59:59.000Z

410

Twisted covariant noncommutative self-dual gravity  

Science Conference Proceedings (OSTI)

A twisted covariant formulation of noncommutative self-dual gravity is presented. The formulation for constructing twisted noncommutative Yang-Mills theories is used. It is shown that the noncommutative torsion is solved at any order of the {theta} expansion in terms of the tetrad and some extra fields of the theory. In the process the first order expansion in {theta} for the Plebanski action is explicitly obtained.

Estrada-Jimenez, S.; Garcia-Compean, H.; Obregon, O.; Ramirez, C. [Centro de Estudios en Fisica y Matematicas Basicas y Aplicadas, Universidad Autonoma de Chiapas, Calle 4 Oriente Norte 1428, Tuxtla Gutierrez, Chiapas (Mexico); Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, P.O. Box 14-740, 07000 Mexico D.F. (Mexico); Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Monterrey, PIIT, Via del Conocimiento 201, Autopista nueva al Aeropuerto km 9.5, 66600, Apodaca Nuevo Leon (Mexico); Instituto de Fisica de la Universidad de Guanajuato, P.O. Box E-143, 37150, Leon Gto. (Mexico); Facultad de Ciencias Fisico Matematicas, Universidad Autonoma de Puebla, P.O. Box 1364, 72000, Puebla (Mexico)

2008-12-15T23:59:59.000Z

411

Flipped spinfoam vertex and loop gravity  

E-Print Network (OSTI)

We introduce a vertex amplitude for 4d loop quantum gravity. We derive it from a conventional quantization of a Regge discretization of euclidean general relativity. This yields a spinfoam sum that corrects some difficulties of the Barrett-Crane theory. The second class simplicity constraints are imposed weakly, and not strongly as in Barrett-Crane theory. Thanks to a flip in the quantum algebra, the boundary states turn out to match those of SO(3) loop quantum gravity -- the two can be identified as eigenstates of the same physical quantities -- providing a solution to the problem of connecting the covariant SO(4) spinfoam formalism with the canonical SO(3) spin-network one. The vertex amplitude is SO(3) and SO(4)-covariant. It rectifies the triviality of the intertwiner dependence of the Barrett-Crane vertex, which is responsible for its failure to yield the correct propagator tensorial structure. The construction provides also an independent derivation of the kinematics of loop quantum gravity and of the result that geometry is quantized.

Jonathan Engle; Roberto Pereira; Carlo Rovelli

2007-08-09T23:59:59.000Z

412

Geometry and symmetries in lattice spinor gravity  

SciTech Connect

Lattice spinor gravity is a proposal for regularized quantum gravity based on fermionic degrees of freedom. In our lattice model the local Lorentz symmetry is generalized to complex transformation parameters. The difference between space and time is not put in a priori, and the euclidean and the Minkowski quantum field theory are unified in one functional integral. The metric and its signature arise as a result of the dynamics, corresponding to a given ground state or cosmological solution. Geometrical objects as the vierbein, spin connection or the metric are expectation values of collective fields built from an even number of fermions. The quantum effective action for the metric is invariant under general coordinate transformations in the continuum limit. The action of our model is found to be also invariant under gauge transformations. We observe a 'geometrical entanglement' of gauge- and Lorentz-transformations due to geometrical objects transforming non-trivially under both types of symmetry transformations. - Highlights: Black-Right-Pointing-Pointer We formulate the geometrical aspects of a proposal for a lattice regularized model of quantum gravity. Black-Right-Pointing-Pointer The vierbein shows an entanglement between Lorentz symmetry and gauge symmetry. Black-Right-Pointing-Pointer Euclidean and Minkowski signatures of the collective metric and the vierbein are described within the same functional integral.

Wetterich, C., E-mail: c.wetterich@thphys.uni-heidelberg.de

2012-09-15T23:59:59.000Z

413

Distinguishing Modified Gravity from Dark Energy  

E-Print Network (OSTI)

The acceleration of the universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark energy models. Modifications of general relativity are expected to be scale-independent on super-horizon scales and scale-dependent on sub-horizon scales. For scale-independent modifications, utilizing the conservation of the curvature scalar and a parameterized post-Newtonian formulation of cosmological perturbations, we derive results for large scale structure growth, weak gravitational lensing, and cosmic microwave background anisotropy. For scale-dependent modifications, inspired by recent $f(R)$ theories we introduce a parameterization for the gravitational coupling $G$ and the post-Newtonian parameter $\\gamma$. These parameterizations provide a convenient formalism for testing general relativity. However, we find that if dark energy is generalized to include both entropy and shear stress perturbations, and the dynamics of dark energy is unknown a priori, then modified gravity cannot in general be distinguished from dark energy using cosmological linear perturbations.

Edmund Bertschinger; Phillip Zukin

2008-01-16T23:59:59.000Z

414

Supermassive galactic centre with repulsive gravity  

E-Print Network (OSTI)

Repulsive gravity has its origin in the 1939 article of Oppenheimer and Snyder which describes a collapsar, that is an idealized star of non-interacting material (dust) collapsing under its own gravity. The stellar material has a final state resembling a football, that is a significant part of it is concentrated in a thin surface shell. An interior pressure is exerted by the strong gravitational field, equivalent to a negative mass. However, the OS solution has been misunderstood, the shell's position being incorrectly identified with the "event horizon" in black-hole theory. While half the material is concentrated in a shell occupying a small fraction of the radius, some material is spread throughout the interior, unlike the concentration in a black hole's singularity. We deal with the singularity in density at the shell surface, by including Fermi pressure of degenerate electrons for a shell density comparable to a solar mass-sized white dwarf. Because the high-density region is concentrated in a shell, instead of at the centre as in a black hole, our conclusion is that repulsive gravity enables the existence of supermassive white dwarfs.

Trevor W. Marshall; Max K. Wallis

2013-03-18T23:59:59.000Z

415

Primordial nucleosynthesis in conformal Weyl gravity  

DOE Green Energy (OSTI)

Recently conformal Weyl gravity has been considered as a candidate alternative gravity theory. This fourth-order theory is attractive because it is the only metric theory of gravity which is invariant under local conformal transformations of the metric. The authors calculate the primordial light element abundances in this theory. The major difference from the standard cosmology is that the universe expands far more slowly throughout the nucleosynthesis epoch. The production of {sup 4}He depends strongly on {eta}, the ratio of baryons to photons. For {eta} = 10{sup {minus}8} the mass fraction of {sup 4}He is X{sub 4} {approx_equal} 0.25 and the number densities relative to hydrogen for {sup 2}H, {sup 3}He and {sup 7}Li are n({sup 2}H)/n(H) {approx_equal} 9 {times} 10{sup {minus}20}, n({sup 3}He)/n(H) {approx_equal}4 {times} 10{sup {minus}18} and n({sup 7}Li)/n(H) {approx_equal} 10{sup {minus}13}. This value of {eta} corresponds to a baryon mass density close to the standard model critical density. However, adjusting {eta} to give a reasonable helium yield forces the deuterium and lithium yields to be small enough that the theory cannot be reconciled with observations.

Knox, L.; Kosowsky, A. [Univ. of Chicago, IL (United States). Enrico Fermi Inst.]|[Fermi National Accelerator Lab., Batavia, IL (United States)

1993-10-01T23:59:59.000Z

416

Lorentz covariance of loop quantum gravity  

SciTech Connect

The kinematics of loop gravity can be given a manifestly Lorentz-covariant formulation: the conventional SU(2)-spin-network Hilbert space can be mapped to a space K of SL(2,C) functions, where Lorentz covariance is manifest. K can be described in terms of a certain subset of the projected spin networks studied by Livine, Alexandrov and Dupuis. It is formed by SL(2,C) functions completely determined by their restriction on SU(2). These are square-integrable in the SU(2) scalar product, but not in the SL(2,C) one. Thus, SU(2)-spin-network states can be represented by Lorentz-covariant SL(2,C) functions, as two-component photons can be described in the Lorentz-covariant Gupta-Bleuler formalism. As shown by Wolfgang Wieland in a related paper, this manifestly Lorentz-covariant formulation can also be directly obtained from canonical quantization. We show that the spinfoam dynamics of loop quantum gravity is locally SL(2,C)-invariant in the bulk, and yields states that are precisely in K on the boundary. This clarifies how the SL(2,C) spinfoam formalism yields an SU(2) theory on the boundary. These structures define a tidy Lorentz-covariant formalism for loop gravity.

Rovelli, Carlo; Speziale, Simone [Centre de Physique Theorique de Luminy, Case 907, F-13288 Marseille (France)

2011-05-15T23:59:59.000Z

417

The Gravity Dual of the Ising Model  

E-Print Network (OSTI)

We evaluate the partition function of three dimensional theories of gravity in the quantum regime, where the AdS radius is Planck scale and the central charge is of order one. The contribution from the AdS vacuum sector can - with certain assumptions - be computed and equals the vacuum character of a minimal model CFT. The torus partition function is given by a sum over geometries which is finite and computable. For generic values of Newton's constant G and the AdS radius L the result has no Hilbert space interpretation, but in certain cases it agrees with the partition function of a known CFT. For example, the partition function of pure Einstein gravity with G=3L equals that of the Ising model, providing evidence that these theories are dual. We also present somewhat weaker evidence that the 3-state and tricritical Potts models are dual to pure higher spin theories of gravity based on SL(3) and E_6, respectively.

Alejandra Castro; Matthias R. Gaberdiel; Thomas Hartman; Alexander Maloney; Roberto Volpato

2011-11-08T23:59:59.000Z

418

The Gravity Dual of the Ising Model  

E-Print Network (OSTI)

We evaluate the partition function of three dimensional theories of gravity in the quantum regime, where the AdS radius is Planck scale and the central charge is of order one. The contribution from the AdS vacuum sector can - with certain assumptions - be computed and equals the vacuum character of a minimal model CFT. The torus partition function is given by a sum over geometries which is finite and computable. For generic values of Newton's constant G and the AdS radius L the result has no Hilbert space interpretation, but in certain cases it agrees with the partition function of a known CFT. For example, the partition function of pure Einstein gravity with G=3L equals that of the Ising model, providing evidence that these theories are dual. We also present somewhat weaker evidence that the 3-state and tricritical Potts models are dual to pure higher spin theories of gravity based on SL(3) and E_6, respectively.

Castro, Alejandra; Hartman, Thomas; Maloney, Alexander; Volpato, Roberto

2011-01-01T23:59:59.000Z

419

Airborne measurements of carbonaceous aerosols in southern Africa during  

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

Airborne measurements of carbonaceous aerosols in southern Africa during Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season Title Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season Publication Type Journal Article LBNL Report Number LBNL-50880 Year of Publication 2003 Authors Kirchstetter, Thomas W., Tihomir Novakov, and Peter V. Hobbs Journal Journal of Geophysical Research - Atmospheres Keywords black carbon, evolved gas analysis, light absorption, organic carbon, positive sampling artifact, SAFARI Abstract Particulate matter collected aboard the University of Washington's Convair-580 research aircraft over southern Africa during the dry, biomass burning season was analyzed for total carbon, organic carbon, and black carbon contents using thermal and optical methods. Samples were collected in smoke plumes of burning savanna and in regional haze. A known artifact, produced by the adsorption of organic gases on the quartz filter substrates used to collect the particulate matter samples, comprised a significant portion of the total carbon collected. Consequently, conclusions derived from the data are greatly dependent on whether or not organic carbon concentrations are corrected for this artifact. For example, the estimated aerosol co-albedo (1 - single scattering albedo), which is a measure of aerosol absorption, of the biomass smoke samples is 60% larger using corrected organic carbon concentrations. Thus, the corrected data imply that the biomass smoke is 60% more absorbing than do the uncorrected data. The black carbon to (corrected) organic carbon mass ratio (BC/OC) of smoke plume samples (0.18±0.06) is lower than that of samples collected in the regional haze (0.25±0.08). The difference may be due to mixing of biomass smoke with background air characterized by a higher BC/OC ratio. A simple source apportionment indicates that biomass smoke contributes about three-quarters of the aerosol burden in the regional haze, while other sources (e.g., fossil fuel burning) contribute the remainder.

420

A detailed calibration of a stack monitor used in the measurement of airborne radionuclides at a high energy proton accelerator  

E-Print Network (OSTI)

A detailed calibration of a stack monitor used in the measurement of airborne radionuclides at a high energy proton accelerator

Vaziri, K; Cossairt, J D; Böhnlein, D J; Elwyn, A J

1996-01-01T23:59:59.000Z

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421

GPS/INS navigation precision and its effect on airborne radio occultation retrieval accuracy  

Science Conference Proceedings (OSTI)

An airborne radio occultation (RO) system has been developed to retrieve atmospheric profiles of refractivity, moisture, and temperature. The long-term objective of such a system is deployment on commercial aircraft to increase the quantity of moisture ... Keywords: Airborne radio occultation, GPS/INS precision, Retrieval accuracy

Paytsar Muradyan; Jennifer S. Haase; Feiqin Xie; James L. Garrison; Justin Voo

2011-07-01T23:59:59.000Z

422

Forecasting airborne pollen concentration time series with neural and neuro-fuzzy models  

Science Conference Proceedings (OSTI)

Forecasting airborne pollen concentrations is one of the most studied topics in aerobiology, due to its crucial application to allergology. The most used tools for this problem are single lineal regressions and autoregressive models (ARIMA). Notwithstanding, ... Keywords: Aerobiology, Airborne pollen, Forecasting, Neuro-fuzzy, Time series

José Luis Aznarte M.; José Manuel Benítez Sánchez; Diego Nieto Lugilde; Concepción de Linares Fernández; Consuelo Díaz de la Guardia; Francisca Alba Sánchez

2007-05-01T23:59:59.000Z

423

AIRBORNE RESEARCH & SURVEY FACILITY (ARSF) http://arsf.nerc.ac.uk  

E-Print Network (OSTI)

instruments can be made available for special applications: Large-format RC-10 aerial survey cameraAIRBORNE RESEARCH & SURVEY FACILITY (ARSF) http://arsf.nerc.ac.uk ANNOUNCEMENT OF OPPORTUNITY 2009 OCTOBER 2008 The Airborne Research & Survey Facility (ARSF) invites direct access applications for UK

424

NERC AIRBORNE RESEARCH & SURVEY FACILITY (ARSF) http://www.nerc.ac.uk/arsf/home.htm  

E-Print Network (OSTI)

-12 microns, 320 spatial pixels) Large-format RC-10 aerial survey camera, with images being suppliedNERC AIRBORNE RESEARCH & SURVEY FACILITY (ARSF) http://www.nerc.ac.uk/arsf/home.htm SPECIAL OF PROPOSALS: FRIDAY 9 OCTOBER 2009 The Airborne Research & Survey Facility (ARSF) invites applications

425

Biomass and Bioenergy 31 (2007) 646655 Estimating biomass of individual pine trees using airborne lidar  

E-Print Network (OSTI)

Biomass and Bioenergy 31 (2007) 646­655 Estimating biomass of individual pine trees using airborne biomass and bio-energy feedstocks. The overall goal of this study was to develop a method for assessing aboveground biomass and component biomass for individual trees using airborne lidar data in forest settings

426

Source Apportionment of Airborne Particulate Matter using Inorganic and  

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

Source Apportionment of Airborne Particulate Matter using Inorganic and Source Apportionment of Airborne Particulate Matter using Inorganic and Organic Species as Tracers Title Source Apportionment of Airborne Particulate Matter using Inorganic and Organic Species as Tracers Publication Type Journal Article Year of Publication 2012 Authors Wang, Yungang, Philip K. Hopke, X. Xia, Oliver V. Rattigan, David C. Chalupa, and M. J. Source Journal Atmospheric Environment Volume 55 Start Page 525 Pagination 525-532 Date Published 01/2012 Keywords source apportionment positive matrix factorization (pmf) particulate matter (pm) molecular markers (mm) aethalometer delta-c Abstract Source apportionment is typically performed on chemical composition data derived from particulate matter (PM) samples. However, many common sources no longer emit significant amounts of characteristic trace elements requiring the use of more comprehensive chemical characterization in order to fully resolve the PM sources. Positive matrix factorization (EPA PMF, version 4.1) was used to analyze 24-hr integrated molecular marker (MM), secondary inorganic ions, trace elements, carbonaceous species and light absorption data to investigate sources of PM2.5 in Rochester, New York between October 2009 and October 2010 to explore the role of specific MMs. An eight-factor solutionwas found for which the factors were identified as isoprene secondary organic aerosol (SOA), airborne soil, other SOA, diesel emissions, secondary sulfate, wood combustion, gasoline vehicle, and secondary nitrate contributing 6.9%, 12.8%, 3.7%, 7.8%, 45.5%, 9.1%, 7.9%, and 6.3% to the average PM2.5 concentration, respectively Concentrations of pentacosane, hexacosane, heptacosane, and octacosane in the gasoline vehicles factor were larger compared to diesel emissions. Aethalometer Delta-C was strongly associated with wood combustion. The compounds, n-heptacosanoic acid and n-octacosanoic acid, occasionally used in the past as tracers for road dust, were found to largely associate with SOA in this study. In comparison with a standard PMF analyses without MM, inclusion of themwas necessary to resolve SOA and wood combustion factors in urban areas.

427

Airborne Instrumentation Needs for Climate and Atmospheric Research  

SciTech Connect

Observational data are of fundamental importance for advances in climate and atmospheric research. Advances in atmospheric science are being made not only through the use of ground-based and space-based observations, but also through the use of in-situ and remote sensing observations acquired on instrumented aircraft. In order for us to enhance our knowledge of atmospheric processes, it is imperative that efforts be made to improve our understanding of the operating characteristics of current instrumentation and of the caveats and uncertainties in data acquired by current probes, as well as to develop improved observing methodologies for acquisition of airborne data.

McFarquhar, Greg; Schmid, Beat; Korolev, Alexei; Ogren, John A.; Russell, P. B.; Tomlinson, Jason M.; Turner, David D.; Wiscombe, Warren J.

2011-10-06T23:59:59.000Z

428

Prospecting by sampling and analysis of airborne particulates and gases  

DOE Patents (OSTI)

A method is claimed for prospecting by sampling airborne particulates or gases at a ground position and recording wind direction values at the time of sampling. The samples are subsequently analyzed to determine the concentrations of a desired material or the ratios of the desired material to other identifiable materials in the collected samples. By comparing the measured concentrations or ratios to expected background data in the vicinity sampled, one can select recorded wind directions indicative of the upwind position of the land-based source of the desired material.

Sehmel, G.A.

1984-05-01T23:59:59.000Z

429

Measurements of Ocean Surface Backscattering Using an Airborne 94-GHz Cloud Radar—Implication for Calibration of Airborne and Spaceborne W-Band Radars  

Science Conference Proceedings (OSTI)

Backscattering properties of the ocean surface have been widely used as a calibration reference for airborne and spaceborne microwave sensors. However, at millimeter-wave frequencies, the ocean surface backscattering mechanism is still not well ...

Lihua Li; Gerald M. Heymsfield; Lin Tian; Paul E. Racette

2005-07-01T23:59:59.000Z

430

Comparison of Airborne In Situ, Airborne Radar–Lidar, and Spaceborne Radar–Lidar Retrievals of Polar Ice Cloud Properties Sampled during the POLARCAT Campaign  

Science Conference Proceedings (OSTI)

This study illustrates the high potential of RALI, the French airborne radar–lidar instrument, for studying cloud processes and evaluating satellite products when satellite overpasses are available. For an Arctic nimbostratus ice cloud collected ...

Julien Delanoë; Alain Protat; Olivier Jourdan; Jacques Pelon; Mathieu Papazzoni; Régis Dupuy; Jean-Francois Gayet; Caroline Jouan

2013-01-01T23:59:59.000Z

431

Gravity Probe B experiment cannot sense torsion of spacetime: on Poincar\\'e gauge theory of gravity and its equations of motion  

E-Print Network (OSTI)

Ever since E.Cartan in the 1920s enriched the geometric framework of general relativity (GR) by introducing a {\\it torsion} of spacetime, the question arose whether one could find a measurement technique for detecting the presence of a torsion field. Mao et al.(2007) claimed that the rotating quartz balls in the gyroscopes of the Gravity Probe B experiment, falling freely on an orbit around the Earth, should "feel" the torsion. Similarly, March et al.(2011) argue with the precession of the Moon and the Mercury and extend later their considerations to the Lageos satellite.--- A consistent theory of gravity with torsion emerged during the early 1960's as gauge theory of the Poincar\\'e group. This Poincar\\'e gauge theory of gravity incorporates as simplest viable cases the Einstein-Cartan(-Sciama-Kibble) theory (EC), the teleparallel equivalent GR|| of GR, and GR itself. So far, PG and, in particular, the existence of torsion have {\\it not} been experimentally confirmed. However, PG is to be considered as the st...

Hehl, Friedrich W; Puetzfeld, Dirk

2013-01-01T23:59:59.000Z

432

The Doppler Aerosol Wind Lidar (DAWN) Airborne, Wind-Profiling, Coherent-Detection Lidar System: Overview and Preliminary Flight Results  

Science Conference Proceedings (OSTI)

The first airborne wind measurements of a pulsed, 2-micron solid-state, high-energy, wind-profiling lidar system for airborne measurements are presented. The laser pulse energy is the highest to date in an eyesafe airborne wind lidar system. This ...

Michael J. Kavaya; Jeffrey Y. Beyon; Grady J. Koch; Mulugeta Petros; Paul J. Petzar; Upendra N. Singh; Bo C. Trieu; Jirong Yu

433

Wide-area, Sub-decimetre Positioning for Airborne LiDAR Surveys Using  

E-Print Network (OSTI)

Airborne LiDAR surveys produce high-resolution, very accurate surface elevation models which are used for many applications in surveying and civil engineering, as well as for flood prevention and mitigation, monitoring coastal erosion and land subsidence, etc. The key to producing high quality elevation products is very precise geolocation and orientation (or “georeferencing”) of the LiDAR instrument at the times when the measurements are made, obtained with a combination of on-board GNSS and inertial sensors. The usual practice is to deploy reference GPS/GNSS land receivers in the area where the aircraft will be flying, and to obtain a precise trajectory by means of the short-baseline differential GNSS technique. This could mean installing and operating receivers at many sites during a flight mission if the area surveyed is a large one. In this paper, an example of an alternative approach will be presented: using as reference receivers those of a sparse network of Continuously Operating Reference Stations (CORS) in New South Wales known as CORSnet-NSW, and a wide-area GNSS technique for obtaining the aircraft trajectory with sub-decimetre accuracy even with baseline lengths of several hundred kilometres. This may be comparable in precision and accuracy to the short-baseline

Oscar L. Colombo; Shane Brunker; Glenn Jones; Volker Janssen

2009-01-01T23:59:59.000Z

434

New Agegraphic Dark Energy in $f(R)$ Gravity  

E-Print Network (OSTI)

In this paper we study cosmological application of new agegraphic dark energy density in the $f(R)$ gravity framework. We employ the new agegraphic model of dark energy to obtain the equation of state for the new agegraphic energy density in spatially flat universe. Our calculation show, taking $nenergy model in flat universe in the modified gravity cosmology framework. Also we develop a reconstruction scheme for the modified gravity with $f(R)$ action.

Setare, M R

2009-01-01T23:59:59.000Z

435

New Agegraphic Dark Energy in $f(R)$ Gravity  

E-Print Network (OSTI)

In this paper we study cosmological application of new agegraphic dark energy density in the $f(R)$ gravity framework. We employ the new agegraphic model of dark energy to obtain the equation of state for the new agegraphic energy density in spatially flat universe. Our calculation show, taking $nenergy model in flat universe in the modified gravity cosmology framework. Also we develop a reconstruction scheme for the modified gravity with $f(R)$ action.

M. R. Setare

2009-08-03T23:59:59.000Z

436

AdS waves as exact solutions to quadratic gravity  

SciTech Connect

We give an exact solution of the quadratic gravity in D dimensions. The solution is a plane-fronted wave metric with a cosmological constant. This metric solves not only the full quadratic gravity field equations but also the linearized ones which include the linearized equations of the recently found critical gravity. A subset of the solutions change the asymptotic structure of the anti-de Sitter space due to their logarithmic behavior.

Guellue, Ibrahim; Sisman, Tahsin Cagri; Tekin, Bayram [Department of Physics, Middle East Technical University, 06531 Ankara (Turkey); Guerses, Metin [Department of Mathematics, Faculty of Sciences Bilkent University, 06800 Ankara (Turkey)

2011-04-15T23:59:59.000Z

437

Gravity Couplings in the Standard-Model Extension  

E-Print Network (OSTI)

The Standard-Model Extension (SME) is an action-based expansion describing general Lorentz violation for known matter and fields, including gravity. In this talk, I will discuss the Lorentz-violating gravity couplings in the SME. Toy models that match the SME expansion, including vector and two-tensor models, are reviewed. Finally I discuss the status of experiments and observations probing gravity coefficients for Lorentz violation.

Bailey, Quentin G

2010-01-01T23:59:59.000Z

438

Solar System experiments do not yet veto modified gravity models  

E-Print Network (OSTI)

The dynamical equivalence between modified and scalar-tensor gravity theories is revisited and it is concluded that it breaks down in the limit to general relativity. A gauge-independent analysis of cosmological perturbations in both classes of theories lends independent support to this conclusion. As a consequence, the PPN formalism of scalar-tensor gravity and Solar System experiments do not veto modified gravity, as previously thought.

Valerio Faraoni

2006-07-05T23:59:59.000Z

439

Repetitive precision gravity studies at the Cerro Prieto and Heber geothermal fields  

DOE Green Energy (OSTI)

To study subsidence and mass removal, a precise gravity network was established on 60 permanent monuments in the Cerro Prieto geothermal field in early 1978, and repeated annually through early 1981; the survey was tied to two bedrock sites outside the limits of the current production zone. The looping technique of station occupation was utilized, in which occupation of the base was followed by occupation of several stations, followed by a return to the base. Use of two LaCoste and Romberg gravity meters, and replication of values within loops as well as entire loops, enhanced precision such that the median standard deviations of the base-to-station differences, reduced to observed gravity values, ranged from 7 to 15 microgals for individual surveys. The smaller values were obtained as field and data reduction techniques were improved and experience was gained. A similar survey was initiated in the Heber area just north of the Mexican border in early 1980. It too was established on permanent monuments, was tied to bedrock stations outside the geothermal area, and used multiple repetitions of values with two meters to achieve high precision.

Grannell, R.B.

1982-09-01T23:59:59.000Z

440

An improved topographic mapping technique from airborne lidar: application in a forested hillside  

Science Conference Proceedings (OSTI)

We developed a robust method to reconstruct a digital terrain model DTM by classifying raw light detection and ranging lidar points into ground and non-ground points with the help of the Progressive Terrain Fragmentation PTF method. PTF applies iterative ...

Jun-Hak Lee, GregoryS. Biging, JohnD. Radke, JoshuaB. Fisher

2013-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "techniques airborne gravity" 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

Exercise protocols during short-radius centrifugation for artificial gravity  

E-Print Network (OSTI)

Long-duration spaceflight results in severe physiological deconditioning, threatening the success of interplanetary travel. Exercise combined with artificial gravity provided by centrifugation may be the comprehensive ...

Edmonds, Jessica Leigh

2008-01-01T23:59:59.000Z

442

Ground Gravity Survey At Newberry Caldera Area (DOE GTP) | Open...  

Open Energy Info (EERE)

GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Newberry Caldera Area (DOE GTP) Exploration Activity Details Location Newberry Caldera Area...

443

Ground Gravity Survey At Under Steamboat Springs Area (Warpinski...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al., 2002) Exploration Activity...

444

Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2004) Exploration Activity Details...

445

Ground Gravity Survey At Lake City Hot Springs Area (Warpinski...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Lake City Hot Springs Area (Warpinski, Et Al., 2004) Exploration Activity...

446

Reconstruction of modified gravity with ghost dark energy models  

E-Print Network (OSTI)

In this work, we reconstruct the $f(R)$ modified gravity for different ghost and generalized ghost dark energy models in FRW flat universe, which describe the accelerated expansion of the universe. The equation of state of reconstructed $f(R)$ - gravity has been calculated. We show that the corresponding $f(R)$ gravity of ghost dark energy model can behave like phantom or quintessence. We also show that the equation of state of reconstructed $f(R)$ gravity for generalized ghost model can transit from quintessence regime to the phantom regime as indicated by recent observations.

Khodam-Mohammadi, A

2012-01-01T23:59:59.000Z

447

Lorentz Invariant phenomenological model of quantum gravity: A minimalistic presentation  

SciTech Connect

The purpose of this paper is to give a minimalistic and self-contained presentation of a Lorentz Invariant phenomenological model of Quantum Gravity.

Bonder, Yuri [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico Apartado Postal 70-543, Distrito Federal 04510 (Mexico)

2012-08-24T23:59:59.000Z

448

Ground Gravity Survey At Dixie Valley Geothermal Field Area ...  

Open Energy Info (EERE)

In Dixie Valley, Nevada Retrieved from "http:en.openei.orgwindex.php?titleGroundGravitySurveyAtDixieValleyGeothermalFieldArea(Blackwell,EtAl.,2009)&oldid38834...

449

Ground Gravity Survey At Under Steamboat Springs Area (Warpinski...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al., 2004) Exploration Activity...

450

Ground Gravity Survey At Walker Lake Valley Area (Shoffner, Et...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Walker Lake Valley Area (Shoffner, Et Al., 2010) Exploration Activity...

451

Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood...  

Open Energy Info (EERE)

to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood & Mabey, 1978) Exploration Activity...

452

Hidden Lorentz symmetry of the Horava - Lifshitz gravity  

E-Print Network (OSTI)

In this letter it is shown that the Horava-Lifshitz gravity theory admits Lorentz symmetry preserving preferred global time foliation of the spacetime.

Jakub Rembielinski

2013-09-03T23:59:59.000Z

453

Gravity wave coupling of the lower and middle atmosphere.  

E-Print Network (OSTI)

??A method of inferring tropospheric gravity wave source characteristics from middle atmosphere observations has been adapted from previous studies for use with MF radar observations… (more)

Love, Peter Thomas

2009-01-01T23:59:59.000Z

454

Jefferson Lab Science Series - Detecting Einstein's Gravity Waves  

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

Science Series Video Archive Next Video (Symmetry) Symmetry Detecting Einstein's Gravity Waves Dr. David Shoemaker - Massachusetts Institute of Technology March 18, 1997 LIGO...

455

Effects of Gravity on the Columnar to Equiaxed Transition in ...  

Science Conference Proceedings (OSTI)

The effects of gravity, thermal natural convection and dendrite transport were integrated into the model. Simulations of vertical directional solidification of an ...

456

Gravity in Randall-Sundrum two D-brane model  

E-Print Network (OSTI)

We analyse Randall-Sundrum two D-brane model by linear perturbation and then consider the linearised gravity on the D-brane. The qualitative contribution from the Kaluza-Klein modes of gauge fields to the coupling to the gravity on the brane will be addressed. As a consequence, the gauge fields localised on the brane are shown not to contribute to the gravity on the brane at large distances. Although the coupling between gauge fields and gravity appears in the next order, the ordinary coupling cannot be realised.

Tetsuya Shiromizu; Keitaro Takahashi; Yoshiaki Himemoto; Shuto Yamamoto

2004-07-30T23:59:59.000Z

457

The Link Between Gravity Recovery and Hydrometallurgy - TMS  

Science Conference Proceedings (OSTI)

Aug 1, 2003 ... The Link Between Gravity Recovery and Hydrometallurgy: The Case of Gold by A.R. Laplante and W. Staunton ...

458

Can gravity be added to Pilot Wave models?  

E-Print Network (OSTI)

The purpose of this paper is to come up with one of the many possible schemes of "adding" gravity to Pilot Wave models.

Sverdlov, Roman

2010-01-01T23:59:59.000Z

459

Polytropic and Chaplygin f(R)-gravity models  

E-Print Network (OSTI)

We reconstruct different f(R)-gravity models corresponding to the polytropic, standard Chaplygin, generalized Chaplygin, modified Chaplygin and modified variable Chaplygin gas dark energy models. We also obtain the equation of state parameters of the corresponding f(R)-gravity models which describe the accelerated expansion of the universe. We conclude that although the equation of state parameters of the obtained f(R)-gravities can behave like phantom or quintessence dark energy models, they cannot justify the transition from the quintessence state to the phantom regime. Furthermore, the polytropic and Chaplygin f(R)-gravity models in de Sitter space can satisfy the inflation condition.

K. Karami; M. S. Khaledian

2010-10-13T23:59:59.000Z

460

Regional Gravity Survey of the Northern Great Salt Lake Desert...  

Open Energy Info (EERE)

of the Northern Great Salt Lake Desert and Adjacent Areas in Utah, Nevada, and Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Regional Gravity...

Note: This page contains sample records for the topic "techniques airborne gravity" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Evolution of Gold Gravity Recovery in Grinding Circuits - A Critical ...  

Science Conference Proceedings (OSTI)

Presentation Title, Evolution of Gold Gravity Recovery in Grinding Circuits - A Critical .... Selective Separations of Gold and Contaminants from Various Gold and ...

462

Ground Gravity Survey At Snake River Plain Region (DOE GTP) ...  

Open Energy Info (EERE)

Snake River Plain Region (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Snake River Plain Region (DOE GTP)...

463

Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2002) | Open  

Open Energy Info (EERE)

Jump to: navigation, search Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove Fort Area (Warpinski, Et Al., 2002) Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes The project at Cove Fort/Sulphurdale in Utah, T26S R6/7W, is concerned with locating and drilling a 900-meter well to explore the western extension of the Cove Fort-Sulphurdale geothermal area. The geophysical exploration consisted of resistivity, ground magnetic, and microgravity surveys that were made to site the well in an optimum location. References N. R. Warpinski, A. R. Sattlerl, D. A. Sanchez (2002) Geothermal Resource Exploration And Definition Project

464

Testing general scalar-tensor gravity and massive gravity with cluster lensing  

E-Print Network (OSTI)

We explore the possibility of testing modified gravity exhibiting the Vainshtein mechanism against observations of cluster lensing. We work in the most general scalar-tensor theory with second-order field equations (Horndeski's theory), and derive static and spherically symmetric solutions, for which the scalar field is screened below a certain radius. It is found that the essential structure of the problem in the most general case can be captured by the program of classifying Vainshtein solutions out of different solutions to a quintic equation, as has been performed in the context of massive gravity. The key effect on gravitational lensing is that the second derivative of the scalar field can substantially be large at the transition from screened to unscreened regions, leaving a dip in the convergence. This allows us to put observational constraints on parameters characterizing the general scalar-tensor modification of gravity. We demonstrate how this occurs in massive gravity as an example, and discuss its observational signatures in cluster lensing.

Tatsuya Narikawa; Tsutomu Kobayashi; Daisuke Yamauchi; Ryo Saito

2013-02-10T23:59:59.000Z

465

Conservation laws for vacuum tetrad gravity  

E-Print Network (OSTI)

Ten conservation laws in useful polynomial form are derived from a Cartan form and Exterior Differential System (EDS) for the tetrad equations of vacuum relativity. The Noether construction of conservation laws for well posed EDS is introduced first, and an illustration given, deriving 15 conservation laws of the free field Maxwell Equations from symmetries of its EDS. The Maxwell EDS and tetrad gravity EDS have parallel structures, with their numbers of dependent variables, numbers of generating 2-forms and generating 3-forms, and Cartan character tables all in the ratio of 1 to 4. They have 10 corresponding symmetries with the same Lorentz algebra, and 10 corresponding conservation laws.

Frank B. Estabrook

2005-08-20T23:59:59.000Z

466

Conservation of energy and Gauss Bonnet gravity  

E-Print Network (OSTI)

It is shown how can be made the classification of all tensors constructed from the Riemann tensor that verify the conservation of gravitational energy momentum. More precisely we explain that there exists a unique tensor of degree n in the Riemann tensor and its contractions that verifies the conservation of energy. We show that this tensor, only because it obeys this degree n structure as well as energy conservation, two facts which are true in all dimensions, verifies in dimension 2n this striking particularity of being Euler gravity. We stick here to the case n=2 but explain briefly why the general case is similar.

Christophe Real

2006-12-21T23:59:59.000Z

467

Geophysics IV. Gravity, Magnetic, and Magnetotelluric Methods  

SciTech Connect

During the past two decades, the technology of geophysics has exploded. At the same time, the petroleum industry has been forced to look for more and more subtle traps in more and more difficult terrain. The choice of papers in this geophysics reprint volume reflects this evolution. The papers were chosen to help geologists, not geophysicists, enhance their knowledge of geophysics. Math-intensive papers were excluded because those papers are relatively esoteric and have limited applicability for most geologists. This volume concentrates on gravity, magnetic, and magnetotelluric methods. Each of the 10 papers were abstracted and indexed for the U.S. Department of Energy's Energy Data Base.

Beaumont, E.A.; Foster, N.H. (comps.)

1989-01-01T23:59:59.000Z

468

Bringing Together Gravity and the Quanta  

E-Print Network (OSTI)

Due to its underlying gauge structure, teleparallel gravity achieves a separation between inertial and gravitational effects. It can, in consequence, describe the isolated gravitational interaction without resorting to the equivalence principle, and is able to provide a tensorial definition for the energy-momentum density of the gravitational field. Considering the conceptual conflict between the local equivalence principle and the nonlocal uncertainty principle, the replacement of general relativity by its teleparallel equivalent can be considered an important step towards a prospective reconciliation between gravitation and quantum mechanics.

R. Aldrovandi; L. C. T. Guillen; J. G. Pereira; K. H. Vu

2006-03-30T23:59:59.000Z

469

The dualities of 3D dilaton gravity  

E-Print Network (OSTI)

We investigate Brans-Dicke dilaton gravity theories in 2+1 dimensions. We show that the reduced field equations for solutions with diagonal metric and depending only on one spacetime coordinate have a continuous O(2) symmetry. Using this symmetry we derive general static and cosmological solutions of the theory. The action of the discrete group O(2,Z) on the space of the solutions is discussed. Three-dimensional string effective theory and three-dimensional general relativity are discussed in detail. In particular, we find that the previously discovered black string solution is dual to a spacetime with a conical singularity.

Mariano Cadoni

1996-06-17T23:59:59.000Z

470

Gravity duals for non-relativistic CFTs  

E-Print Network (OSTI)

We attempt to generalize the AdS/CFT correspondence to non-relativistic conformal field theories which are invariant under Galilean transformations. Such systems govern ultracold atoms at unitarity, nucleon scattering in some channels, and more generally, a family of universality classes of quantum critical behavior. We construct a family of metrics which realize these symmetries as isometries. They are solutions of gravity with negative cosmological constant coupled to pressureless dust. We discuss realizations of the dust, which include a bulk superconductor. We develop the holographic dictionary and compute some two-point correlators. A strange aspect of the correspondence is that the bulk geometry has two extra noncompact dimensions.

Koushik Balasubramanian; John McGreevy

2008-04-25T23:59:59.000Z

471

Thermodynamics of 5D dilaton-gravity  

Science Conference Proceedings (OSTI)

We calculate the free energy, spatial string tension and Polyakov loop of the gluon plasma using the dilaton potential of Ref. [1] in the dilaton-gravity theory of AdS/QCD. The free energy is computed from the Black Hole solutions of the Einstein equations in two ways: first, from the Bekenstein-Hawking proportionality of the entropy with the area of the horizon, and secondly from the Page-Hawking computation of the free energy. The finite temperature behaviour of the spatial string tension and Polyakov loop follow from the corresponding string theory in AdS{sub 5}. Comparison with lattice data is made.

Megias, E. [Institute for Theoretical Physics, University of Heidelberg (Germany); Instituto de Fisica Teorica CSIC-UAM, Universidad Autonoma de Madrid (Spain)

2011-05-23T23:59:59.000Z

472

Maxwell's equations, linear gravity, and twistors  

SciTech Connect

A detailed outline is presented of several convergent points of view connecting the self-dual and anti-self-dual fields with their free data. This is doen for the Maxwell and for linearized gravity as exemplifying the approaches. The Sparling equation provides one tool of great power and characterizes one approach. The twistor theory of Penrose yields another equally powerful point of view. The links between these two basic approaches given in this paper provide a unification that allows workers and others with interest in this area to proceed more readily toward the goal of understanding the full nonlinear Einstein equations.

Kozameh, C.N.; Newman, E.T.; Porter, J.R.

1984-11-01T23:59:59.000Z

473

Seven-Dimensional Gravity with Topological Terms  

E-Print Network (OSTI)

We construct new seven-dimensional gravity by adding two topological terms to the Einstein-Hilbert action. For certain choice of the coupling constants, these terms may be related to the R^4 correction to the 3-form field equation of eleven-dimensional supergravity. We derive the full set of the equations of motion. We find that the static spherically-symmetric black holes are unmodified by the topological terms. We obtain squashed AdS_7, and also squashed seven spheres and Q^{111} spaces in Euclidean signature.

H. Lu; Yi Pang

2009-12-30T23:59:59.000Z

474

Lorentz Invariance Violation in Modified Gravity  

E-Print Network (OSTI)

We consider an environmentally dependent violation of Lorentz invariance in scalar-tensor models of modified gravity where General Relativity is retrieved locally thanks to a screening mechanism. We find that fermions have a modified dispersion relation and would go faster than light in an anisotropic and space-dependent way along the scalar field lines of force. We analyse briefly the OPERA results and show that they could be reproduced with chameleon models. We suggest that neutrinos emitted radially, at different energies, and observed on the other side of the earth would provide a test of these models.

Brax, Philippe

2012-01-01T23:59:59.000Z

475

Gamma Ray Burst Neutrinos Probing Quantum Gravity  

E-Print Network (OSTI)

Very high energy, short wavelength, neutrinos may interact with the space-time foam predicted by theories of quantum gravity. They would propagate like light through a crystal lattice and be delayed, with the delay depending on the energy. This will appear to the observer as a violation of Lorenz invariance. Back of the envelope calculations imply that observations of neutrinos produced by gamma ray bursts may reach Planck-scale sensitivity. We revisit the problem considering two essential complications: the imprecise timing of the neutrinos associated with their poorly understood production mechanism in the source and the indirect nature of their energy measurement made by high energy neutrino telescopes.

M. C. Gonzalez-Garcia; F. Halzen

2006-11-28T23:59:59.000Z

476

Robust approach to f(R) gravity  

Science Conference Proceedings (OSTI)

We consider metric f(R) theories of gravity without mapping them to their scalar-tensor counterpart, but using the Ricci scalar itself as an ''extra'' degree of freedom. This approach avoids then the introduction of a scalar-field potential that might be ill defined (not single valued). In order to explicitly show the usefulness of this method, we focus on static and spherically symmetric spacetimes and deal with the recent controversy about the existence of extended relativistic objects in certain class of f(R) models.

Jaime, Luisa G. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico Distrito Federal 04510 (Mexico); Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Apartado Postal 50-542, Mexico Distrito Federal 04510 (Mexico); Patino, Leonardo [Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Apartado Postal 50-542, Mexico Distrito Federal 04510 (Mexico); Salgado, Marcelo [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico Distrito Federal 04510 (Mexico)

2011-01-15T23:59:59.000Z

477

Principal facts for gravity stations in the Darrough Known Geothermal Resource Area (KGRA), Nevada  

DOE Green Energy (OSTI)

The latitude, longitude, elevation, observed gravity, theoretical gravity, terrain correction, free-air correction, Bougner correction, and Bougner anomaly are tabulated for 71 gravity stations in the Darrough KGRA, Nevada area. (WHK)

Peterson, D.L.; Dansereau, D.A.

1976-01-01T23:59:59.000Z

478

Principal facts for a gravity survey of Summer Lake Known Geothermal Resource Area, Oregon  

DOE Green Energy (OSTI)

Gravity survey data are tabulated for 73 stations. Site latitude, longitude, elevation, observed gravity, theoretical gravity, free-air correction, Bouguer correction, and the simple Bouguer anomaly are included. (WHK)

Peterson, D.L.; Meyer, R.F.

1976-01-01T23:59:59.000Z

479

Cosmography of f(R) gravity  

E-Print Network (OSTI)

It is nowadays accepted that the universe is undergoing a phase of accelerated expansion as tested by the Hubble diagram of Type Ia Supernovae (SNeIa) and several LSS observations. Future SNeIa surveys and other probes will make it possible to better characterize the dynamical state of the universe renewing the interest in cosmography which allows a model independent analysis of the distance - redshift relation. On the other hand, fourth order theories of gravity, also referred to as $f(R)$ gravity, have attracted a lot of interest since they could be able to explain the accelerated expansion without any dark energy. We show here how it is possible to relate the cosmographic parameters (namely the deceleration $q_0$, the jerk $j_0$, the snap $s_0$ and the lerk $l_0$ parameters) to the present day values of $f(R)$ and its derivatives $f^{(n)}(R) = d^nf/dR^n$ (with $n = 1, 2, 3$) thus offering a new tool to constrain such higher order models. Our analysis thus offers the possibility to relate the model independ...

Capozziello, S; Salzano, V

2008-01-01T23:59:59.000Z

480

Cosmography of f(R) gravity  

E-Print Network (OSTI)

It is nowadays accepted that the universe is undergoing a phase of accelerated expansion as tested by the Hubble diagram of Type Ia Supernovae (SNeIa) and several LSS observations. Future SNeIa surveys and other probes will make it possible to better characterize the dynamical state of the universe renewing the interest in cosmography which allows a model independent analysis of the distance - redshift relation. On the other hand, fourth order theories of gravity, also referred to as $f(R)$ gravity, have attracted a lot of interest since they could be able to explain the accelerated expansion without any dark energy. We show here how it is possible to relate the cosmographic parameters (namely the deceleration $q_0$, the jerk $j_0$, the snap $s_0$ and the lerk $l_0$ parameters) to the present day values of $f(R)$ and its derivatives $f^{(n)}(R) = d^nf/dR^n$ (with $n = 1, 2, 3$) thus offering a new tool to constrain such higher order models. Our analysis thus offers the possibility to relate the model independent results coming from cosmography to the theoretically motivated assumptions of $f(R)$ cosmology.

S. Capozziello; V. F. Cardone; V. Salzano

2008-02-12T23:59:59.000Z

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481

Vacuum energy: quantum hydrodynamics vs quantum gravity  

E-Print Network (OSTI)

We compare quantum hydrodynamics and quantum gravity. They share many common features. In particular, both have quadratic divergences, and both lead to the problem of the vacuum energy, which in the quantum gravity transforms to the cosmological constant problem. We show that in quantum liquids the vacuum energy density is not determined by the quantum zero-point energy of the phonon modes. The energy density of the vacuum is much smaller and is determined by the classical macroscopic parameters of the liquid including the radius of the liquid droplet. In the same manner the cosmological constant is not determined by the zero-point energy of quantum fields. It is much smaller and is determined by the classical macroscopic parameters of the Universe dynamics: the Hubble radius, the Newton constant and the energy density of matter. The same may hold for the Higgs mass problem: the quadratically divergent quantum correction to the Higgs potential mass term is also cancelled by the microscopic (trans-Planckian) degrees of freedom due to thermodynamic stability of the whole quantum vacuum.

G. E. Volovik

2005-05-20T23:59:59.000Z

482

Constraint structure of the three dimensional massive gravity  

Science Conference Proceedings (OSTI)

Constraint analysis of the three-dimensional massive gravity, the so-called new massive gravity, is studied in the Palatini formalism. We show that amongst 6 components of the metric, 2 are dynamical, which is compatible with the existence of one vector massive graviton in the linearized theory (Fierz-Pauli theory).

Sadegh, M.; Shirzad, A. [Department of Physics, Isfahan University of Technology , P.O.Box 84156-83111, Isfahan (Iran, Islamic Republic of); School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O.Box 19395-5531, Tehran (Iran, Islamic Republic of)

2011-04-15T23:59:59.000Z

483

Constraints on Dark Energy Models from Weak Gravity Conjecture  

E-Print Network (OSTI)

We study the constraints on the dark energy model with constant equation of state parameter $w=p/\\rho$ and the holographic dark energy model by using the weak gravity conjecture. The combination of weak gravity conjecture and the observational data gives $wenergy model realized by a scalar field is in swampland.

Chen, Ximing; Gong, Yungui

2008-01-01T23:59:59.000Z

484

Constraints on Dark Energy Models from Weak Gravity Conjecture  

E-Print Network (OSTI)

We study the constraints on the dark energy model with constant equation of state parameter $w=p/\\rho$ and the holographic dark energy model by using the weak gravity conjecture. The combination of weak gravity conjecture and the observational data gives $wenergy model realized by a scalar field is in swampland.

Ximing Chen; Jie Liu; Yungui Gong

2008-06-15T23:59:59.000Z

485

Walking in simulated reduced gravity: mechanical energy fluctuations and exchange  

E-Print Network (OSTI)

Walking in simulated reduced gravity: mechanical energy fluctuations and exchange TIMOTHY M reduced gravity: mechanical energy fluctuations and exchange. J. Appl. Physiol. 86(1): 383­390, 1999.--Walking humans conserve mechanical and, presum- ably, metabolic energy with an inverted pendulum-like ex

Kram, Rodger

486

A note on positive energy of topologically massive gravity  

E-Print Network (OSTI)

I review how "classical SUGRA" embeddability establishes positive energy E for D=3 topologically massive gravity (TMG), with or without a cosmological term, a procedure familiar from D=4 Einstein gravity (GR). It also provides explicit expressions for E. In contrast to GR, E is not manifestly positive, due to the peculiar two-term nature of TMG.

Deser, S

2009-01-01T23:59:59.000Z

487

Gravity Waves in Shear and Implications for Organized Convection  

Science Conference Proceedings (OSTI)

It is known that gravity waves in the troposphere, which are often excited by preexisting convection, can favor or suppress the formation of new convection. Here it is shown that in the presence of wind shear or barotropic wind, the gravity waves ...

Samuel N. Stechmann; Andrew J. Majda

2009-09-01T23:59:59.000Z

488

Gravity on a Dilatonic Gauss-Bonnet Brane World  

E-Print Network (OSTI)

The effective four-dimensional, linearised gravity of a Randall-Sundrum-like brane world model is analysed. The model includes higher order curvature terms (such as the Gauss-Bonnet term) and a scalar field. The resulting brane worlds can have better agreement with observations than the equivalent Einstein gravity models.

Stephen C. Davis

2004-08-18T23:59:59.000Z

489

Three?dimensional group manifold reductions of gravity  

Science Conference Proceedings (OSTI)

We review the three?dimensional group manifold reductions of pure Einstein gravity and we exhibit a new consistent group manifold reduction of gravity when the compactification group manifold is S 3. The new reduction leads to a lower dimensional theory whose gauge group is SU (2).

Román Linares

2005-01-01T23:59:59.000Z

490

Modeling the Hydrological Effect on Local Gravity at Moxa, Germany  

Science Conference Proceedings (OSTI)

A superconducting gravimeter has observed with high accuracy (to within a few nm s?2) and high frequency (1 Hz) the temporal variations in the earth’s gravity field near Moxa, Germany, since 1999. Hourly gravity residuals are obtained by time ...

Shaakeel Hasan; Peter A. Troch; J. Boll; C. Kroner

2006-06-01T23:59:59.000Z

491

Quantum Corrections to Newton's Law in Resummed Quantum Gravity  

E-Print Network (OSTI)

We present the elements of resummed quantum gravity, a new approach to quantum gravity based on the work of Feynman using the simplest example of a scalar field as the representative matter. We show that we get a UV finite quantum correction to Newton's law.

B. F. L. Ward

2004-11-03T23:59:59.000Z

492

COMPUTER SIMULATION OF SINGLE-WELL STEAM ASSISTED GRAVITY DRAINAGE  

E-Print Network (OSTI)

COMPUTER SIMULATION OF SINGLE-WELL STEAM ASSISTED GRAVITY DRAINAGE (SW-SAGD) TR 119 By Keith T of Sensitivity Analysis Cases 32 #12;v List of Figures Figure 1: Steam Assisted Gravity Drainage Concept: Recovery Factor vs. Time for All Cases (10 Years Production) 13 Figure 8: Cumulative Steam-Oil Ratio vs

493

Gravity base, jack-up platform - method and apparatus  

SciTech Connect

The invention relates to an offshore, gravity base, jack-up platform comprising a deck, a gravity base and one or more legs interconnecting the deck and base. The gravity base comprises a generally polygonal shaped, monolithic hull structure with reaction members extending downwardly from the hull to penetrate the waterbed and react to vertical and lateral loads imposed upon the platform while maintaining the gravity hull in a posture elevated above the surface of the waterbed. A method aspect of the invention includes the steps of towing a gravity base, jack-up platform, as a unit, to a preselected offshore site floating upon the gravity hull. During the towing operation, the deck is mounted adjacent the gravity base with a leg or legs projecting through the deck. At a preselected offshore station ballast is added to the gravity base and the platform descends slightly to a posture where the platform is buoyantly supported by the deck. The base is then jacked down toward the seabed and the platform is laterally brought onto station. Ballast is then added to the deck and the reaction members are penetrated into the waterbed to operational soil refusal. Ballast is then ejected from the deck and the deck is jacked to an operational elevation above a predetermined statistical wave crest height.

Herrmann, R.P.; Pease, F.T.; Ray, D.R.

1981-05-05T23:59:59.000Z

494

Aeromagnetic and gravity surveys in the Coso Range, California | Open  

Open Energy Info (EERE)

and gravity surveys in the Coso Range, California and gravity surveys in the Coso Range, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Aeromagnetic and gravity surveys in the Coso Range, California Details Activities (2) Areas (1) Regions (0) Abstract: The effect of an underlying magma reservoir cannot be identified within the complex gravity pattern in the Coso Range, California. Rather, linear gravity contours, which suggest a regional tectonic origin, enclose the location of most of the volcanic activity of the Coso Range. Faults along the edges of northwest trending, magnetic blocks probably provided paths of minimum resistance to the ascending viscous magma that was extruded as rhyolite domes. Dense, magnetic rocks associated with a complex mafic pluton 9 km in diameter form a relatively impermeable north border of

495

Generalized Misner-Sharp Energy in f(R) Gravity  

E-Print Network (OSTI)

We study generalized Misner-Sharp energy in $f(R)$ gravity in a spherically symmetric spacetime. We find that unlike the cases of Einstein gravity and Gauss-Bonnet gravity, the existence of the generalized Misner-Sharp energy depends on a constraint condition in the $f(R)$ gravity. When the constraint condition is satisfied, one can define a generalized Misner-Sharp energy, but it cannot always be written in an explicit quasi-local form. However, such a form can be obtained in a FRW universe and for static spherically symmetric solutions with constant scalar curvature. In the FRW universe, the generalized Misner-Sharp energy is nothing but the total matter energy inside a sphere with radius $r$, which acts as the boundary of a finite region under consideration. The case of scalar-tensor gravity is also briefly discussed.

Cai, Rong-Gen; Hu, Ya-Peng; Ohta, Nobuyoshi

2009-01-01T23:59:59.000Z

496

Non-trivial 2+1-Dimensional Gravity  

E-Print Network (OSTI)

We analyze 2+1-dimensional gravity in the framework of quantum gauge theory. We find that Einstein gravity has a trivial physical subspace which reflects the fact that the classical solution in empty space is flat. Therefore we study massive gravity which is not trivial. In the limit of vanishing graviton mass we obtain a non-trivial massless theory different from Einstein gravity. We derive the interaction from descent equations and obtain the cosmological topologically massive gravity. However, in addition to Einstein and Chern-Simons coupling we need coupling to fermionic ghost and anti-ghost fields and to a vector-graviton field with the same mass as the graviton.

D. R. Grigore; G. Scharf

2010-08-07T23:59:59.000Z

497

Application Of Airborne Thermal Infrared Imagery To Geothermal Exploration  

Open Energy Info (EERE)

Thermal Infrared Imagery To Geothermal Exploration Thermal Infrared Imagery To Geothermal Exploration Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Application Of Airborne Thermal Infrared Imagery To Geothermal Exploration Details Activities (0) Areas (0) Regions (0) Abstract: Burlington Northern (BN) conducted TIR surveys using a fixed wing aircraft over 17 different geothermal prospects in Washington, Montana and Wyoming because of this remote sensing tool's ability to detect variations in the heat emitted from the earth's surface. The surveys were flown at an average elevation of 5000 ft. above the ground surface which gave a spatial resolution of approximately 7 feet diameter. BN found thermal activity which had not been recognized previously in some prospects (e.g., Lester,

498

New Approaches to Differential Mobility Analysis for Airborne Measurements  

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

to Differential Mobility to Differential Mobility Analysis for Airborne Measurements Rick Flagan Chemical Engineering and Environmental Science and Engineering California Institute of Technology Pasadena, CA 91125 Support: NSF, ONR, Davidow Foundation Differential Mobility Analysis Air Sample Aerosol Charger/Neutralizer (Atmospheric Pressure Chemical Ionization) Sheath Air Q sh ~ 10 Q a Volumetric flow rate Q s Exhaust Q ex =Q sh Differential Mobility Analyzer DMA (Aerodynamic Analog of Sector Mass Spectrometer) E F e =eE F drag = 6πµR p V C slip (λ /R p ) CPC Q a =Q s Steady or Scanned Voltage Migration Velocity * Mobility * Peclet number for migration v E = Z p E Z p = n p e k B T D Pe mig = electrophoretic migration diffusive transport = bv E D = bn p eE k B T Singly Charged Particles  Radial DMA  Cylindrical DMA E = V b Pe = eV k B T E =

499

Initial assessment of an airborne Ku-band polarimetric SAR.  

SciTech Connect

Polarimetric synthetic aperture radar (SAR) has been used for a variety of dual-use research applications since the 1940's. By measuring the direction of the electric field vector from radar echoes, polarimetry may enhance an analyst's understanding of scattering effects for both earth monitoring and tactical surveillance missions. Polarimetry may provide insight into surface types, materials, or orientations for natural and man-made targets. Polarimetric measurements may also be used to enhance the contrast between scattering surfaces such as man-made objects and their surroundings. This report represents an initial assessment of the utility of, and applications for, polarimetric SAR at Ku-band for airborne or unmanned aerial systems.

Raynal, Ann Marie; Doerry, Armin Walter

2013-02-01T23:59:59.000Z

500

Wavenumber–Frequency Spectra of Inertia–Gravity and Mixed Rossby–Gravity Waves in the Equatorial Pacific Ocean  

Science Conference Proceedings (OSTI)

In the 1970s and 1980s, there was considerable interest in near-equatorial variability at periods of days to weeks associated with oceanic equatorial inertia–gravity waves and mixed Rossby–gravity waves. At that time, the measurements available ...

J. Thomas Farrar; Theodore S. Durland

2012-11-01T23:59:59.000Z