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1

Rotating Shadowband Spectroradiometer (RSS) Handbook  

SciTech Connect (OSTI)

The rotating shawdowband spectroradiometer (RSS) implements the same automated shadowbanding technique used by the multifilter rotating shadowband radiometer (MFRSR), and so it too provides spectrally-resolved, direct-normal, diffuse-horizontal, and total-horizontal irradiances, and can be calibrated in situ via Langley regression. The irradiance spectra are measured simultaneously at all spectral elements (pixels) in 360-nm to 1050-nm range.

Kiedron, P; Schlemmer, J; Klassen, M

2005-01-01T23:59:59.000Z

2

Multifilter Rotating Shadowband Radiometer (MFRSR) Handbook  

SciTech Connect (OSTI)

The visible Multifilter Rotating Shadowband Radiometer (MFRSR) is a passive instrument that measures global and diffuse components of solar irradiance at six narrowband channels and one open, or broadband, channel (Harrison et al. 1994). Direct irradiance is not a primary measurement, but is calculated using the diffuse and global measurements. To collect one data record, the MFRSR takes measurements at four different shadowband positions. The first measurement is taken with the shadowband in the nadir (home) position. The next three measurements are, in order, the first side-band, sun-blocked, and second side-band. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. The nominal wavelengths of the narrowband channels are 415, 500, 615, 673, 870, and 940 nm. From such measurements, one may infer the atmosphere's aerosol optical depth at each wavelength. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Harrison and Michalsky 1994) and other atmospheric constituents.

Hodges, GB; Michalsky, JJ

2011-02-07T23:59:59.000Z

3

Removing Systematic Errors from Rotating Shadowband Pyranometer Data Frank Vignola  

E-Print Network [OSTI]

Removing Systematic Errors from Rotating Shadowband Pyranometer Data Frank Vignola Solar Radiation irradiance be- cause they do not require manual adjustment of trackers. However, a RSP requires the use of solar cell based pyranometers which underestimate diffuse irradiance by 20- 30% under clear sky

Oregon, University of

4

ARM Multi-Filter Rotating Shadowband Radiometer (MFRSR): irradiances  

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

The multifilter rotating shadowband radiometer (MFRSR) takes spectral measurements of direct normal, diffuse horizontal and total horizontal solar irradiances. These measurements are at nominal wavelengths of 415, 500, 615, 673, 870, and 940 nm. The measurements are made at a user-specified time interval, usually about one minute or less. The sampling rate for the Atmospheric Radiation Measurement (ARM) Climate Research Facility MFRSRs is 20 seconds. From such measurements, one may infer the atmosphere's optical depth at the wavelengths mentioned above. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Michalsky et al. 1994) and other atmospheric constituents. A silicon detector is also part of the MFRSR. This detector provides a measure of the broadband direct normal, diffuse horizontal and total horizontal solar irradiances. A MFRSR head that is mounted to look vertically downward can measure upwelling spectral irradiances. In the ARM system, this instrument is called a multifilter radiometer (MFR). At the Southern Great Plains (SGP) there are two MFRs; one mounted at the 10-m height and the other at 25 m. At the North Slope of Alaska (NSA) sites, the MFRs are mounted at 10 m. MFRSR heads are also used to measure normal incidence radiation by mounting on a solar tracking device. These are referred to as normal incidence multi-filter radiometers (NIMFRs) and are located at the SGP and NSA sites. Another specialized use for the MFRSR is the narrow field of view (NFOV) instrument located at SGP. The NFOV is a ground-based radiometer (MFRSR head) that looks straight up.

Hodges, Gary

5

The multi-filter rotating shadowband radiometer (MFRSR) - precision infrared radiometer (PIR) platform in Fairbanks: Scientific objectives  

SciTech Connect (OSTI)

The multi-filter rotating shadowband radiometer (MFRSR) and precision infrared radiometer (PIR) have been employed at the Geophysical Institute in Fairbanks to check their performance under arctic conditions. Drawing on the experience of the previous measurements in the Arctic, the PIR was equipped with a ventilator to prevent frost and moisture build-up. We adopted the Solar Infrared Observing Sytem (SIROS) concept from the Southern Great Plains Cloud and Radiation Testbed (CART) to allow implementation of the same data processing software for a set of radiation and meteorological instruments. To validate the level of performance of the whole SIROS prior to its incorporation into the North Slope of Alaska (NSA) Cloud and Radiation Testbed Site instrumental suite for flux radiatin measurements, the comparison between measurements and model predictions will be undertaken to assess the MFRSR-PIR Arctic data quality.

Stamnes, K.; Leontieva, E. [Univ. of Alaska, Fairbanks (United States)

1996-04-01T23:59:59.000Z

6

Comparison of Historical Satellite-Based Estimates of Solar Radiation Resources with Recent Rotating Shadowband Radiometer Measurements: Preprint  

SciTech Connect (OSTI)

The availability of rotating shadow band radiometer measurement data at several new stations provides an opportunity to compare historical satellite-based estimates of solar resources with measurements. We compare mean monthly daily total (MMDT) solar radiation data from eight years of NSRDB and 22 years of NASA hourly global horizontal and direct beam solar estimates with measured data from three stations, collected after the end of the available resource estimates.

Myers, D. R.

2009-03-01T23:59:59.000Z

7

Failure and Redemption of Multifilter Rotating Shadowband Radiometer (MFRSR)/Normal Incidence Multifilter Radiometer (NIMFR) Cloud Screening: Contrasting Algorithm Performance at Atmospheric Radiation Measurement (ARM) North Slope of Alaska (NSA) and Southern Great Plains (SGP) Sites  

SciTech Connect (OSTI)

Well-known cloud-screening algorithms, which are designed to remove cloud-contaminated aerosol optical depths (AOD) from AOD measurements, have shown great performance at many middle-to-low latitude sites around the world. However, they may occasionally fail under challenging observational conditions, such as when the sun is low (near the horizon) or when optically thin clouds with small spatial inhomogeneity occur. Such conditions have been observed quite frequently at the high-latitude Atmospheric Radiation Measurement (ARM) North Slope of Alaska (NSA) sites. A slightly modified cloud-screening version of the standard algorithm is proposed here with a focus on the ARM-supported Multifilter Rotating Shadowband Radiometer (MFRSR) and Normal Incidence Multifilter Radiometer (NIMFR) data. The modified version uses approximately the same techniques as the standard algorithm, but it additionally examines the magnitude of the slant-path line of sight transmittance and eliminates points when the observed magnitude is below a specified threshold. Substantial improvement of the multi-year (1999-2012) aerosol product (AOD and its Angstrom exponent) is shown for the NSA sites when the modified version is applied. Moreover, this version reproduces the AOD product at the ARM Southern Great Plains (SGP) site, which was originally generated by the standard cloud-screening algorithms. The proposed minor modification is easy to implement and its application to existing and future cloud-screening algorithms can be particularly beneficial for challenging observational conditions.

Kassianov, Evgueni I.; Flynn, Connor J.; Koontz, Annette S.; Sivaraman, Chitra; Barnard, James C.

2013-09-11T23:59:59.000Z

8

ARM - Publications: Science Team Meeting Documents: Rotating Shadowband  

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

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9

ARM - Field Campaign - Thin Cloud Rotating Shadowband Radiometer  

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

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10

NREL: MIDC/Oak Ridge National Laboratory Rotating Shadowband Radiometer  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions and Achievements ofLizResultsGeothermal EnergyElizabeth City

11

Design of a Shadowband Spectral Radiometer for the Retrieval of Thin Cloud Optical Depth, Liquid Water Path, and the Effective Radius  

SciTech Connect (OSTI)

The design and operation of a Thin-Cloud Rotating Shadowband Radiometer (TCRSR) described here was used to measure the radiative intensity of the solar aureole and enable the simultaneous retrieval of cloud optical depth, drop effective radius, and liquid water path. The instrument consists of photodiode sensors positioned beneath two narrow metal bands that occult the sun by moving alternately from horizon to horizon. Measurements from the narrowband 415-nm channel were used to demonstrate a retrieval of the cloud properties of interest. With the proven operation of the relatively inexpensive TCRSR instrument, its usefulness for retrieving aerosol properties under cloud-free skies and for ship-based observations is discussed.

Bartholomew M. J.; Reynolds, R. M.; Vogelmann, A. M.; Min, Q.; Edwards, R.; Smith, S.

2011-11-01T23:59:59.000Z

12

Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement  

SciTech Connect (OSTI)

This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, R.; Kobashi, T.; Akiyama, A.; Takagi, S.

2014-05-01T23:59:59.000Z

13

Retrieval of Cloud Phase and Crystal Habit from Multiangle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) Data  

SciTech Connect (OSTI)

A method of retrieving cloud phase and the dominant ice crystal habit from radiances measured by the Multi-angle Imaging Spectro-Radiometer (MISR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) has been developed. The retrieval method takes advantage of the differences in the phase function of various particle shapes as a function of scattering angle. Three case studies are presented which illustrate the retrieval method. A comparison with semi-coincident in situ observations for one case study indicates that the retrieved crystal habits are consistent with the observations.

McFarlane, Sally A.; Marchand, Roger T.; Ackerman, Thomas P.

2005-07-22T23:59:59.000Z

14

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Los Angeles, California (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Stoffel, T.; Andreas, A.

2010-04-26T23:59:59.000Z

15

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Milford, Utah (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

2010-07-14T23:59:59.000Z

16

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); La Ola Lanai, Hawaii (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

2009-07-22T23:59:59.000Z

17

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Cedar City, Utah (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

2010-07-13T23:59:59.000Z

18

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Kalaeloa Oahu, Hawaii (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

2010-03-16T23:59:59.000Z

19

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Los Angeles, California (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Stoffel, T.; Andreas, A.

20

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Cedar City, Utah (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Milford, Utah (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

22

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Kalaeloa Oahu, Hawaii (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

23

Solar Resource & Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); La Ola Lanai, Hawaii (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

24

NREL Vehicle Testing and Integration Facility (VTIF): Rotating Shadowband Radiometer (RSR); Golden, Colorado (Data)  

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

This measurement station at NREL's Vehicle Testing and Integration Facility (VTIF) monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location. The solar measurement instrumentation is also accompanied by meteorological monitoring equipment.

Lustbader, J.; Andreas, A.

25

Sacramento Municipal Utility District (SMUD): Rotating Shadowband Radiometer (RSR); Anatolia - Rancho Cordova, California (Data)  

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

A partnership with industry and U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to collect solar data to support future solar power generation in the United States. The measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location. The solar measurement instrumentation is also accompanied by meteorological monitoring equipment to provide scientists with a complete picture of the solar power possibilities.

Maxey, C.; Andreas, A.

26

Oak Ridge National Laboratory (ORNL); Rotating Shadowband Radiometer (RSR); Oak Ridge, Tennessee (Data)  

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

This measurement station monitors global horizontal, direct normal, and diffuse horizontal irradiance to define the amount of solar energy that hits this particular location.

Maxey, C.; Andreas, A.

27

Ocean Aerosols: The Marine Fast-Rotating Shadow-Band Radiometer Network  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the ContributionsArmsSpeedingSpeedingUnderOccupational HealthOcean Aerosols: The Marine

28

NREL: MIDC/SMUD Anatolia Rotating Shadowband Radiometer (38.55 N, 121.24 W,  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions and Achievements ofLizResultsGeothermal EnergyElizabeth City51 m,

29

Spectroradiometer Intercomparison and Impact on Characterizing Photovoltaic Device Performance: Preprint  

SciTech Connect (OSTI)

Indoor and outdoor testing of photovoltaic (PV) device performance requires the use of solar simulators and natural solar radiation, respectively. This performance characterization requires accurate knowledge of spectral irradiance distribution that is incident on the devices. Spectroradiometers are used to measure the spectral distribution of solar simulators and solar radiation. On September 17, 2013, a global spectral irradiance intercomparison using spectroradiometers was organized by the Solar Radiation Research Laboratory (SRRL) at the National Renewable Energy Laboratory (NREL). This paper presents highlights of the results of this first intercomparison, which will help to decrease systematic inter-laboratory differences in the measurements of the outputs or efficiencies of PV devices and harmonize laboratory experimental procedures.

Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, E.; Kobashi, T.; Akiyama, A.; Takagi, S.

2014-11-01T23:59:59.000Z

30

ARM: Shortwave Array Spectroradiometer-Hemispheric, VISible channel, high-sun angles [a0 data is uncalibrated  

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

Shortwave Array Spectroradiometer-Hemispheric, VISible channel, high-sun angles [a0 data is uncalibrated

Flynn, Connor

31

ARM: Shortwave Array Spectroradiometer-Hemispheric, VISible channel, low-sun angles [a0 data is uncalibrated  

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

Shortwave Array Spectroradiometer-Hemispheric, VISible channel, low-sun angles [a0 data is uncalibrated

Flynn, Connor

32

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated  

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

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated

Flynn, Connor

33

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated  

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

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated

Flynn, Connor

34

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated  

SciTech Connect (OSTI)

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated

Flynn, Connor

2011-03-22T23:59:59.000Z

35

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated  

SciTech Connect (OSTI)

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated

Flynn, Connor

2011-03-22T23:59:59.000Z

36

Solar Resource and Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Escalante Tri-State - Prewitt, New Mexico (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

37

Solar Resource and Meteorological Assessment Project (SOLRMAP): Rotating Shadowband Radiometer (RSR); Escalante Tri-State - Prewitt, New Mexico (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

2012-11-03T23:59:59.000Z

38

Mapping daily snow//ice shortwave broadband albedo from Moderate Resolution Imaging Spectroradiometer (MODIS): The improved  

E-Print Network [OSTI]

and global energy balances when snow coverage is variable. In the polar regions, the high surface albedo acts the Advanced Very High Resolution Radiometer (AVHRR) satellite data in polar regions [De Abreu et al., 1994 variable in surface energy balance calculations. The Moderate Resolution Imaging Spectroradiometer (MODIS

Liang, Shunlin

39

Final Report for Grant DE-FG02-90ER61072  

SciTech Connect (OSTI)

This is the final report for the work done by our research group at the Atmospheric Sciences Research Center for the US DOE Atmopheric Radiation Measurement (ARM) Program. We were involved from the beginning of the ARM effort; we designed the Multi-filter Rotating Shadowband Spectroradiometer (MFRSR) which was widely deployed (and still operational in ARM) and through the years did a wide variety of data analysis on the returned data from these instruments. We also developed the Rotating Shadowband Spectroradiometer, which ARM deployed and also still deploys. Many scientific papers have been written using the data from these instruments, and the ongoing data streams remain part of the current ARM effort. Earlier reports contain our progress from previous grant periods, this report covers the last period and provides references to published work.

Lee Harrison

2006-02-20T23:59:59.000Z

40

Cloud Model Evaluation Using Radiometric Measurements from the Airborne Multiangle Imaging Spectroradiometer (AirMISR)  

SciTech Connect (OSTI)

Detailed information on cloud properties is needed to vigorously test retrieval algorithms for satellite and ground-based remote sensors. The inherent complexity of clouds makes this information difficult to obtain from observations alone and cloud resolving models are often used to generating synthetic datasets that can be used as proxies for real data. We test the ability of a cloud resolving model to reproduce cloud structure in a case study of low-level clouds observed by the Earth Observing System (EOS) validation program in north central Oklahoma on March 3, 2000. A three-dimensional radiative transfer model is applied to synthetic cloud properties generated by a high-resolution three-dimensional cloud model in order to simulate the top of atmosphere radiances. These synthetic radiances are then compared with observations from the airborne Multiangle Imaging SpectroRadiometer (AirMISR), flown on the NASA ER-2 high-altitude aircraft.

Ovtchinnikov, Mikhail; Marchand, Roger T.

2007-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Use of Spectroradiometers to Guide In-season Nitrogen Fertilizer Applications in Irrigated Cotton in West Texas  

E-Print Network [OSTI]

1 Use of Spectroradiometers to Guide In-season Nitrogen Fertilizer Applications in Irrigated Cotton in West Texas Following water, nitrogen (N) is the most important constraint to upland cotton production. Most of the cotton in the semiarid western U.S.A. is irrigated, and in areas like the Southern High

Behmer, Spencer T.

42

Solar Resource & Meteorological Assessment Project (SOLRMAP): Southwest Solar Research Park (Formerly SolarCAT) Rotating Shadowband Radiometer (RSR); Phoenix, Arizona (Data)  

SciTech Connect (OSTI)

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

2010-09-27T23:59:59.000Z

43

Solar Resource & Meteorological Assessment Project (SOLRMAP): Southwest Solar Research Park (Formerly SolarCAT) Rotating Shadowband Radiometer (RSR); Phoenix, Arizona (Data)  

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

The U.S. Department of Energy's National Renewable Energy Laboratory collaborates with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result is high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

Wilcox, S.; Andreas, A.

44

Retrieval of Optical And Size Parameters of Aerosols Utilizing a Multi-Filter Rotating Shadowband Radiometer and Inter-Comparison with CIMEL Sun Photometer and  

E-Print Network [OSTI]

Radiometer and Inter-Comparison with CIMEL Sun Photometer and MICROTOPS Sun Photometer Antonio Aguirre Radiometer (MFRSR) and comparing with data from a CIMEL Sun Photometer and a MICROTOPS Sun Photometer. Using the inverse cosine of the angle between the sun and the vertical. A Langley plot provides a linear regression

45

ASRC RSS Data  

SciTech Connect (OSTI)

Once every minute between sunrise and sunset the Rotating Shadowband Spectroradiometer (RSS) measures simultaneously three irradiances: total horizontal, diffuse horizontal and direct normal in near ultraviolet, visible and near infrared range (approx. 370nm-1050nm) at 512 (RSS103) or 1024 (RSS102 and RSS105) adjacent spectral resolving elements (pixels). The resolution is pixel (wavelength) dependent and it differs from instrument to instrument. The reported irradiances are cosine response corrected. And their radiometric calibration is based on incandescent lamp calibrators that can be traced to the NIST irradiance scale. The units are W/m2/nm.

Kiedron, Peter

2008-01-15T23:59:59.000Z

46

ASRC RSS Data  

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

Once every minute between sunrise and sunset the Rotating Shadowband Spectroradiometer (RSS) measures simultaneously three irradiances: total horizontal, diffuse horizontal and direct normal in near ultraviolet, visible and near infrared range (approx. 370nm-1050nm) at 512 (RSS103) or 1024 (RSS102 and RSS105) adjacent spectral resolving elements (pixels). The resolution is pixel (wavelength) dependent and it differs from instrument to instrument. The reported irradiances are cosine response corrected. And their radiometric calibration is based on incandescent lamp calibrators that can be traced to the NIST irradiance scale. The units are W/m2/nm.

Kiedron, Peter

47

Advanced Ultraviolet Spectroradiometer  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout the BuildingInnovation PortalScience ofTechnologyMoreAdvanced

48

LABORATORY VI ROTATIONAL DYNAMICS  

E-Print Network [OSTI]

wheels are everywhere. Balls spin when they are thrown. The earth rotates about its axis. Rotations to predict the outcome of a rotational system. · Choose a useful system when using rotational kinematics of systems. PREPARATION: Read Paul M. Fishbane: Chapter 9, Section 9-1; Chapter 5, Section 5-4. You should

Minnesota, University of

49

Evaluation of Radiometric Measurements from the NASA Multiangle Imaging Spectroradiometer (MISR): Two- and Three-Dimensional Radiative Transfer Modeling of an Inhomogeneous Stratocumulus Cloud Deck  

SciTech Connect (OSTI)

In December 1999, NASA launched the Terra satellite. This platform carries five instruments that measure important properties of the Earth climate system. One of these instruments is the Multiangle Imaging Spectroradiometer, or MISR. This instrument measures light reflected from the Earth at a spatial resolution of 275-1100 m, at four wavelengths (446, 558, 672, and 866 nm), and at nine different viewing angles that vary from +70 to -70 degrees along the direction of flight [Diner et al., 2002]. These multiangle data have the potential to provide information on aerosols, surface, and cloud characteristics that compliments traditional single-view-direction satellite measurements. Before this potential can be realized, the accuracy of the satellite radiance measurements must be carefully assessed, and the implications of the radiometric accuracy on remote-sensing algorithms must be evaluated. In this article, we compare MISR multiangle measurements against two-dimensional (2-D) and 3-D radiative transfer calculations from an inhomogeneous cloud scene. Inputs to the radiative transfer code are based entirely on independently gathered data (ground-based radar, lidar, microwave radiometer, in situ aircraft data, etc.). The 2-D radiative transfer calculations compare favorably near nadir and in most of the forward scattering directions, but differ by as much as 10% in the backscattering directions. Using 3-D radiative transfer modeling, we show that this difference is due to the 3-D structure of the cloud deck, including variations in the cloud top height on scales less than 275 m, which are not resolved in the 2-D simulations. Comparison of the 2-D calculations to the MISR measurements, after accounting for the 3-D structure, show residual differences that are less than 4% at all angles at the MISR blue and green wavelengths. The comparison also reveals that the MISR measurements at the red and near-infrared wavelengths are too bright relative to measurements in the blue and green bands. On the basis of the results of this study, along with results from five other comparisons, the MISR calibration is being adjusted to reduce the red and nearinfrared Radiances.

Marchand, Roger T.; Ackerman, Thomas P.

2004-09-29T23:59:59.000Z

50

A Rotating Holographic Superconductor  

E-Print Network [OSTI]

In this paper we initiate the study of SSB in 3+1 dimensional rotating, charged, asymptotically AdS black holes. The theory living on their boundary, R x S^2, has the interpretation of a 2+1 dimensional rotating holographic superconductor. We study the appearance of a marginal mode of the condensate as the temperature is decreased. We find that the transition temperature depends on the rotation. At temperatures just below T_c, the transition temperature at zero rotation, there exists a critical value of the rotation, which destroys the superconducting order. This behaviour is analogous to the emergence of a critical applied magnetic field and we show that the superconductor in fact produces the expected London field in the planar limit.

Julian Sonner

2009-03-31T23:59:59.000Z

51

Rotational Quantum Friction  

E-Print Network [OSTI]

We investigate the frictional forces due to quantum fluctuations acting on a small sphere rotating near a surface. At zero temperature, we find the frictional force near a surface to be several orders of magnitude larger than that for the sphere rotating in vacuum. For metallic materials with typical conductivity, quantum friction is maximized by matching the frequency of rotation with the conductivity. Materials with poor conductivity are favored to obtain large quantum frictions. For semiconductor materials that are able to support surface plasmon polaritons, quantum friction can be further enhanced by several orders of magnitude due to the excitation of surface plasmon polaritons.

Rongkuo Zhao; Alejandro Manjavacas; F. Javier García de Abajo; J. B. Pendry

2012-08-21T23:59:59.000Z

52

Electromagnetic rotational actuation.  

SciTech Connect (OSTI)

There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

Hogan, Alexander Lee

2010-08-01T23:59:59.000Z

53

Faraday rotation in graphene  

E-Print Network [OSTI]

We study magneto--optical properties of monolayer graphene by means of quantum field theory methods in the framework of the Dirac model. We reveal a good agreement between the Dirac model and a recent experiment on giant Faraday rotation in cyclotron resonance. We also predict other regimes when the effects are well pronounced. The general dependence of the Faraday rotation and absorption on various parameters of samples is revealed both for suspended and epitaxial graphene.

I. V. Fialkovsky; D. V. Vassilevich

2012-11-29T23:59:59.000Z

54

Rotating arc spark plug  

DOE Patents [OSTI]

A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

Whealton, John H.; Tsai, Chin-Chi

2003-05-27T23:59:59.000Z

55

Rotating Aperture System  

DOE Patents [OSTI]

A rotating aperture system includes a low-pressure vacuum pumping stage with apertures for passage of a deuterium beam. A stator assembly includes holes for passage of the beam. The rotor assembly includes a shaft connected to a deuterium gas cell or a crossflow venturi that has a single aperture on each side that together align with holes every rotation. The rotating apertures are synchronized with the firing of the deuterium beam such that the beam fires through a clear aperture and passes into the Xe gas beam stop. Portions of the rotor are lapped into the stator to improve the sealing surfaces, to prevent rapid escape of the deuterium gas from the gas cell.

Rusnak, Brian (Livermore, CA); Hall, James M. (Livermore, CA); Shen, Stewart (Danville, CA); Wood, Richard L. (Santa Fe, NM)

2005-01-18T23:59:59.000Z

56

Space time and rotations  

E-Print Network [OSTI]

The paper considers the problem of finding the metric of space time around a rotating, weakly gravitating body. Both external and internal metric tensors are consistently found, together with an appropriate source tensor. All tensors are calculated at the lowest meaningful approximation in a power series. The two physical parameters entering the equations (the mass and the angular momentum per unit mass) are assumed to be such that the mass effects are negligible with respect to the rotation effects. A non zero Riemann tensor is obtained. The order of magnitude of the effects at the laboratory scale is such as to allow for experimental verification of the theory.

A. Tartaglia

2002-01-04T23:59:59.000Z

57

Rotating bubble membrane radiator  

DOE Patents [OSTI]

A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

1988-12-06T23:59:59.000Z

58

Rotatable stem and lock  

DOE Patents [OSTI]

A valve stem and lock is disclosed which includes a housing surrounding a valve stem, a solenoid affixed to an interior wall of the housing, an armature affixed to the valve stem and a locking device for coupling the armature to the housing body. When the solenoid is energized, the solenoid moves away from the housing body, permitting rotation of the valve stem.

Deveney, J.E.; Sanderson, S.N.

1981-10-27T23:59:59.000Z

59

Wave-driven Rotation in Supersonically Rotating Mirrors  

SciTech Connect (OSTI)

Supersonic rotation in mirrors may be produced by radio frequency waves. The waves produce coupled diffusion in ion kinetic and potential energy. A population inversion along the diffusion path then produces rotation. Waves may be designed to exploit a natural kinetic energy source or may provide the rotation energy on their own. Centrifugal traps for fusion and isotope separation may benefit from this wave-driven rotation.

A. Fetterman and N.J. Fisch

2010-02-15T23:59:59.000Z

60

Rotating equipment shop testing  

SciTech Connect (OSTI)

Poor performance of machinery after commissioning at first draws comments on whether the purchase specification was in order, whether there were any lapses in stage inspection or whether the performance test procedure was inadequate. Attempts are initiated to find out whether there were any deviations in operating conditions from the purchase specifications, inadvertent lapses in operation or any mistakes by the maintenance Dept. It will be of some interest to mention here a difference between operating companies who have taken over existing plants and engineering consulting companies who have engineered and constructed the plants. The specialist rotating machinery group of engineering consultant companies have a good understanding of what can be achieved at the manufacturer's test facility due to repeated dealings with manufacturers. However, operating company understanding varies from one organization to the next. This article gives an overview of rotating machinery with respect to test objectives and field problems.

Godse, A.G. (Kuwait National Petroleum Co., Shuaiba (KW))

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Sample rotating turntable kit for infrared spectrometers  

DOE Patents [OSTI]

An infrared spectrometer sample rotating turntable kit has a rotatable sample cup containing the sample. The infrared spectrometer has an infrared spectrometer probe for analyzing the sample and the rotatable sample cup is adapted to receive the infrared spectrometer probe. A reflectance standard is located in the rotatable sample cup. A sleeve is positioned proximate the sample cup and adapted to receive the probe. A rotator rotates the rotatable sample cup. A battery is connected to the rotator.

Eckels, Joel Del (Livermore, CA); Klunder, Gregory L. (Oakland, CA)

2008-03-04T23:59:59.000Z

62

Rotating drum filter  

DOE Patents [OSTI]

A perforated drum (10) rotates in a coaxial cylindrical housing (18) having three circumferential ports (19,22,23), and an axial outlet (24) at one end. The axis (11) is horizontal. A fibrous filter medium (20) is fed through a port (19) on or near the top of the housing (81) by a distributing mechanism (36) which lays a uniform mat (26) of the desired thickness onto the rotating drum (10). This mat (26) is carried by the drum (10) to a second port (23) through which dirty fluid (13) enters. The fluid (13) passes through the filter (26) and the cleaned stream (16) exits through the open end (15) of the drum (10) and the axial port (24) in the housing (18). The dirty filter material (20) is carried on to a third port (22) near the bottom of the housing (18) and drops into a receiver (31) from which it is continuously removed, cleaned (30), and returned (32) to the charging port (36) at the top. To support the filter mat, the perforated cylinder may carry a series of tines (40), shaped blades (41), or pockets, so that the mat (26) will not fall from the drum (10) prematurely. To minimize risk of mat failure, the fluid inlet port (23) may be located above the horizontal centerline (11).

Anson, Donald (Worthington, OH)

1990-01-01T23:59:59.000Z

63

Aerosol Optical Depth Value-Added Product Report  

SciTech Connect (OSTI)

This document describes the process applied to retrieve aerosol optical depth (AOD) from multifilter rotating shadowband radiometers (MFRSR) and normal incidence multifilter radiometers (NIMFR) operated at the ARM Climate Research Facility’s ground-based facilities.

Koontz, A; Hodges, G; Barnard, J; Flynn, C; Michalsky, J

2013-03-17T23:59:59.000Z

64

Galactic microlensing with rotating binaries  

E-Print Network [OSTI]

The influence of rotating binary systems on the light curves of galactic microlensing events is studied. Three different rotating binary systems are discussed: a rotating binary lens, a rotating binary source, and the motion of the earth around the sun (parallax effect). The most dramatic effects arise from the motion of a binary lens because of the changes of the caustic structure with time. I discuss when the treatment of a microlensing event with a static binary model is appropriate. It is shown that additional constraints on the unknown physical quantities of the lens system arise from a fit with a rotating binary lens as well as from the earth-around-sun motion. For the DUO#2 event, a fit with a rotating binary lens is presented.

M. Dominik

1997-09-09T23:59:59.000Z

65

Slowly rotating homogeneous masses revisited  

E-Print Network [OSTI]

Hartle's model for slowly rotating stars has been extensively used to compute equilibrium configurations of slowly rotating stars to second order in perturbation theory in General Relativity, given a barotropic equation of state (EOS). A recent study based on the modern theory of perturbed matchings show that the model must be amended to accommodate EOS's in which the energy density does not vanish at the surface of the non rotating star. In particular, the expression for the change in mass given in the original model, i.e. a contribution to the mass that arises when the perturbations are chosen so that the pressure of the rotating and non rotating configurations agree, must be modified with an additional term. In this paper, the amended change in mass is calculated for the case of constant density stars.

Reina, Borja

2015-01-01T23:59:59.000Z

66

Rotational response of superconductors: magneto-rotational isomorphism and rotation-induced vortex lattice  

E-Print Network [OSTI]

The analysis of nonclassical rotational response of superfluids and superconductors was performed by Onsager (in 1949) \\cite{Onsager} and London (in 1950) \\cite{London} and crucially advanced by Feynman (in 1955) \\cite{Feynman}. It was established that, in thermodynamic limit, neutral superfluids rotate by forming---without any threshold---a vortex lattice. In contrast, the rotation of superconductors at angular frequency ${\\bf \\Omega}$---supported by uniform magnetic field ${\\bf B}_L\\propto {\\bf \\Omega}$ due to surface currents---is of the rigid-body type (London Law). Here we show that, neglecting the centrifugal effects, the behavior of a rotating superconductor is identical to that of a superconductor placed in a uniform fictitious external magnetic filed $\\tilde{\\bf H}=- {\\bf B}_L$. In particular, the isomorphism immediately implies the existence of two critical rotational frequencies in type-2 superconductors.

Egor Babaev; Boris Svistunov

2014-03-03T23:59:59.000Z

67

Cooling system for rotating machine  

DOE Patents [OSTI]

An electrical machine comprising a rotor is presented. The electrical machine includes the rotor disposed on a rotatable shaft and defining a plurality of radial protrusions extending from the shaft up to a periphery of the rotor. The radial protrusions having cavities define a fluid path. A stationary shaft is disposed concentrically within the rotatable shaft wherein an annular space is formed between the stationary and rotatable shaft. A plurality of magnetic segments is disposed on the radial protrusions and the fluid path from within the stationary shaft into the annular space and extending through the cavities within the radial protrusions.

Gerstler, William Dwight (Niskayuna, NY); El-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Lokhandwalla, Murtuza (Clifton Park, NY); Alexander, James Pellegrino (Ballston Lake, NY); Quirion, Owen Scott (Clifton Park, NY); Palafox, Pepe (Schenectady, NY); Shen, Xiaochun (Schenectady, NY); Salasoo, Lembit (Schenectady, NY)

2011-08-09T23:59:59.000Z

68

Rotationally invariant multilevel block codes  

E-Print Network [OSTI]

ROTATIONALLY INVARIANT MULTILEVEL BLOCK CODES A Thesis by ANITA KULANDAIVELU Submitted to the Office of Graduate Studies of Texas AfjrM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1993... Major Subject: Electrical Engineering ROTATIONALLY INVARIANT MULTILEVEL BLOCK CODES A Thesis by ANITA KULANDAIVELU Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved...

Kulandaivelu, Anita

1993-01-01T23:59:59.000Z

69

ARM - Field Campaign - ISDAC - Hemispheric Flux Spectroradiometer  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3,CloudgovCampaignsIR Cloud Camera Feasibility Study ARM-

70

Rotational Mixing and Lithium Depletion  

E-Print Network [OSTI]

I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses at a rate which decays with time. New developments related to the possible suppression of mixing at late ages, close binary mergers and their lithium signature, and an alternate origin for dispersion in young cool stars tied to radius anomalies observed in active young stars are discussed. I highlight uncertainties in models of Population II lithium depletion and dispersion related to the treatment of angular momentum loss. Finally, the origins of rotation are tied to conditions in the pre-main sequence, and there is thus some evidence that enviroment and planet formation could impact stellar rotational properties. This may be related to recent observational evidence for cluster to cluster variations in lithium depletion and a connection between the presence of planets and s...

Pinsonneault, M H

2010-01-01T23:59:59.000Z

71

Mechanics of Rotating Isolated Horizons  

E-Print Network [OSTI]

Black hole mechanics was recently extended by replacing the more commonly used event horizons in stationary space-times with isolated horizons in more general space-times (which may admit radiation arbitrarily close to black holes). However, so far the detailed analysis has been restricted to non-rotating black holes (although it incorporated arbitrary distortion, as well as electromagnetic, Yang-Mills and dilatonic charges). We now fill this gap by first introducing the notion of isolated horizon angular momentum and then extending the first law to the rotating case.

Abhay Ashtekar; Christopher Beetle; Jerzy Lewandowski

2001-04-11T23:59:59.000Z

72

Vacuum friction in rotating particles  

E-Print Network [OSTI]

We study the frictional torque acting on particles rotating in empty space. At zero temperature, vacuum friction transforms mechanical energy into light emission and produces particle heating. However, particle cooling relative to the environment occurs at finite temperatures and low rotation velocities. Radiation emission is boosted and its spectrum significantly departed from a hot-body emission profile as the velocity increases. Stopping times ranging from hours to billions of years are predicted for materials, particle sizes, and temperatures accessible to experiment. Implications for the behavior of cosmic dust are discussed.

A. Manjavacas; F. J. García de Abajo

2010-09-21T23:59:59.000Z

73

Rotational ratchets with dipolar interactions  

E-Print Network [OSTI]

We report results from a computer simulation study on the rotational ratchet effect in systems of magnetic particles interacting via dipolar interactions. The ratchet effect consists of directed rotations of the particles in an oscillating magnetic field, which lacks a net rotating component. Our investigations are based on Brownian dynamics simulations of such many-particle systems. We investigate the influence of both, the random and deterministic contributions to the equations of motion on the ratchet effect. As a main result, we show that dipolar interactions can have an enhancing as well as a dampening effect on the ratchet behavior depending on the dipolar coupling strength of the system under consideration. The enhancement is shown to be caused by an increase in the effective field on a particle generated by neighboring magnetic particles, while the dampening is due to restricted rotational motion in the effective field. Moreover, we find a non-trivial influence of the short-range, repulsive interaction between the particles.

Sebastian Jäger; Sabine H. L. Klapp

2012-10-12T23:59:59.000Z

74

Rotating drum variable depth sampler  

DOE Patents [OSTI]

A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

Nance, Thomas A. (Aiken, SC); Steeper, Timothy J. (Trenton, SC)

2008-07-01T23:59:59.000Z

75

Experiments with Fertilizers on Rotated and Non-Rotated Crops.  

E-Print Network [OSTI]

This is a report of experiments conducted over a period of 14 years to study the effect of fertilizers, manure, removal. of crop residues, and rota- tion on the yield of crops. The fertilizer treatments included superphos- phate; superphosphate and manure...; superphosphate and cottonseed meal; manure; rock phosphate; and rock phosphate and manure. Cotton and corn were grown continuously on the same land and in rotation with oats and cowpeas. The soil responded more readily to nitrogenous than to phosphatic fer...

Reynolds, E. B. (Elbert Brunner)

1928-01-01T23:59:59.000Z

76

Rotation generation and transport in tokamak plasmas  

E-Print Network [OSTI]

Plasma toroidal rotation is a factor important for plasma stability and transport, but it is still a fairly poorly understood area of physics. This thesis focuses on three aspects of rotation: momentum transport, Ohmic ...

Podpaly, Yuri Anatoly

2012-01-01T23:59:59.000Z

77

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

78

Particle entanglement in rotating gases  

SciTech Connect (OSTI)

In this paper, we investigate the particle entanglement in two-dimensional (2D) weakly interacting rotating Bose and Fermi gases. We find that both particle localization and vortex localization can be indicated by particle entanglement. We also use particle entanglement to show the occurrence of edge reconstruction of rotating fermions. The different properties of condensate phase and vortex liquid phase of bosons can be reflected by particle entanglement and in vortex liquid phase we construct the same trial wave function with that in [Phys. Rev. Lett. 87, 120405 (2001)] from the viewpoint of entanglement to relate the ground state with quantum Hall state. Finally, the relation between particle entanglement and interaction strength is studied.

Liu Zhao; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2010-06-15T23:59:59.000Z

79

Accelerating and rotating black holes  

E-Print Network [OSTI]

An exact solution of Einstein's equations which represents a pair of accelerating and rotating black holes (a generalised form of the spinning C-metric) is presented. The starting point is a form of the Plebanski-Demianski metric which, in addition to the usual parameters, explicitly includes parameters which describe the acceleration and angular velocity of the sources. This is transformed to a form which explicitly contains the known special cases for either rotating or accelerating black holes. Electromagnetic charges and a NUT parameter are included, the relation between the NUT parameter $l$ and the Plebanski-Demianski parameter $n$ is given, and the physical meaning of all parameters is clarified. The possibility of finding an accelerating NUT solution is also discussed.

J. B. Griffiths; J. Podolsky

2005-07-06T23:59:59.000Z

80

Alignment of suprathermally rotating grains  

E-Print Network [OSTI]

It is shown, that mechanical alignment can be efficient for suprathermally rotating grains, provided that they drift with supersonic velocities. Such a drift should be widely spread due to both Alfv\\'{e}nic waves and ambipolar diffusion. Moreover, if suprathermal rotation is caused by grain interaction with a radiative flux, it is shown, that mechanical alignment may be present even in the absence of supersonic drift. This means that the range of applicability of mechanical alignment is wider that it is generally accepted and it can rival the paramagnetic one. We also study the latter mechanism and reexamine the interplay between poisoning of active sites and desorption of molecules blocking the access to the active sites of H$_{2}$ formation in order to explain the observed poor alignment of small grains and good alignment of large grains. To have a more comprehensive picture of alignment we briefly discuss the alignment by radiation fluxes and caused by grain magnetic moments.

A. Lazarian

1995-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Rotating concave eddy current probe  

SciTech Connect (OSTI)

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

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

2008-04-01T23:59:59.000Z

82

On the Energy of Rotating Gravitational Waves  

E-Print Network [OSTI]

A class of solutions of the gravitational field equations describing vacuum spacetimes outside rotating cylindrical sources is presented. A subclass of these solutions corresponds to the exterior gravitational fields of rotating cylindrical systems that emit gravitational radiation. The properties of these rotating gravitational wave spacetimes are investigated. In particular, we discuss the energy density of these waves using the gravitational stress-energy tensor.

Bahram Mashhoon; James C. McClune; Enrique Chavez; Hernando Quevedo

1996-09-06T23:59:59.000Z

83

Gravitational duality and rotating solutions  

SciTech Connect (OSTI)

We study how gravitational duality acts on rotating solutions, using the Kerr-NUT black hole as an example. After properly reconsidering how to take into account both electric (i.e. masslike) and magnetic (i.e. NUT-like) sources in the equations of general relativity, we propose a set of definitions for the dual Lorentz charges. We then show that the Kerr-NUT solution has nontrivial such charges. Further, we clarify in which respect Kerr's source can be seen as a mass M with a dipole of NUT charges.

Argurio, Riccardo; Dehouck, Francois [Physique Theorique et Mathematique and International Solvay Institutes, Universite Libre de Bruxelles, C.P. 231, 1050 Bruxelles (Belgium)

2010-03-15T23:59:59.000Z

84

Dual rotating shaft seal apparatus  

DOE Patents [OSTI]

The report is directed to apparatus suitable for transferring torque and rotary motion through a wall in a manner which is essentially gas impermeable. The apparatus can be used for pressurizing, agitating, and mixing fluids and features two ferrofluidic, i.e., ferrometic seals. Each seal is disposed on one of two supported shafts and each shaft is operably connected at one end to a gear mechanism and at its other end to an adjustable coupling means which is to be connected to a rotatable shaft extending through a wall through which torque and rotary motion are to be transferred.

Griggs, J.E.; Newman, H.J.

1983-06-16T23:59:59.000Z

85

Sandia National Laboratories: Rotating Platform  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik SpoerkeSolarCybernetics: DynamicCybernetics: Weigh &FacilityRotating

86

Trirotron: triode rotating beam radio frequency amplifier  

DOE Patents [OSTI]

High efficiency amplification of radio frequencies to very high power levels including: establishing a cylindrical cloud of electrons; establishing an electrical field surrounding and coaxial with the electron cloud to bias the electrons to remain in the cloud; establishing a rotating electrical field that surrounds and is coaxial with the steady field, the circular path of the rotating field being one wavelength long, whereby the peak of one phase of the rotating field is used to accelerate electrons in a beam through the bias field in synchronism with the peak of the rotating field so that there is a beam of electrons continuously extracted from the cloud and rotating with the peak; establishing a steady electrical field that surrounds and is coaxial with the rotating field for high-energy radial acceleration of the rotating beam of electrons; and resonating the rotating beam of electrons within a space surrounding the second field, the space being selected to have a phase velocity equal to that of the rotating field to thereby produce a high-power output at the frequency of the rotating field.

Lebacqz, Jean V. (Stanford, CA)

1980-01-01T23:59:59.000Z

87

Short-Rotation Woody Biomass Sustainability  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Review Short-Rotation Woody Biomass Sustainability Natalie A. Griffiths, Oak Ridge National Laboratory C. Rhett Jackson, University of Georgia Kellie Vache, Oregon State University...

88

Rotation With Industry | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Industry Rotation With Industry 7ROTATIONWITHINDUSTRY.pdf More Documents & Publications Microsoft Word - APRIL 2009 PMCDP Module CHRIS ESS TutorialROTATIONWITHINDUSTRY.doc...

89

The Impact of Rotation on Cluster Dynamics  

E-Print Network [OSTI]

The evolution of rotating, isolated clusters of stars up to core-collapse is investigated with n-body numerical codes. The simulations start off from axisymmetric generalisations of King profiles, with added global angular momentum. In this contribution I report on results obtained for two sets of single-mass cluster simulations. These confirm the more rapid evolution of even mildly-rotating clusters. A model is presented with rotational energy comparable to omega-Centauri's; it reaches core-collapse in less than half the time required for non-rotating model clusters.

Christian Boily

2000-02-23T23:59:59.000Z

90

Control of molecular rotation in the limit of extreme rotational excitation  

E-Print Network [OSTI]

Laser control of molecular rotation is an area of active research. A number of recent studies has aimed at expanding the reach of rotational control to extreme, previously inaccessible rotational states, as well as controlling the directionality of molecular rotation. Dense ensembles of molecules undergoing ultrafast uni-directional rotation, known as molecular superrotors, are anticipated to exhibit unique properties, from spatially anisotropic diffusion and vortex formation to the creation of powerful acoustic waves and tuneable THz radiation. Here we describe our recent progress in controlling molecular rotation in the regime of high rotational excitation. We review two experimental techniques of producing uni-directional rotational wave packets with a "chiral train" of femtosecond pulses and an "optical centrifuge". Three complementary detection methods, enabling the direct observation, characterization and control of the superrotor states, are outlined: the one based on coherent Raman scattering, and two...

Milner, V

2015-01-01T23:59:59.000Z

91

Holographic Superconductors in a Rotating Spacetime  

E-Print Network [OSTI]

We consider holographic superconductors in a rotating black string spacetime. In view of the mandatory introduction of the $A_\\varphi$ component of the vector potential we are left with three equations to be solved. Their solutions show that the effect of the rotating parameter $a$ influences the critical temperature $T_c$ and the conductivity $\\sigma$ in a simple but not trivial way.

Kai Lin; Elcio Abdalla

2014-10-17T23:59:59.000Z

92

Rotating head for rotary drilling rigs  

SciTech Connect (OSTI)

A rotating head is claimed for a rotary drilling rig which is to be secured to the top of a well pipe having an inner rotating portion with an opening therethrough which permits passage of drill pipe, pipe joints, and Kelly tools; the rotating portion has an annular drive rubber formed integrally with the top portion thereof. A rotating head drive bushing having an opening with a cross-sectional shape generally conforming to the cross-section of the Kelly tool to permit only sliding motion therebetween is provided with helical external ridges which produce a disengagable gripping action with the opening in the drive rubber at the top of the rotating portion of the rotating head. The rotating portion has a conventional stripper rubber at the bottom thereof and is mounted with a double roller bearing to provide low friction motion with respect to the fixed portion of the head. The double roller bearing is lubricated with a viscous lubricating material and paddles are provided between the sets of rollers of the double roller bearing for distributing the viscous lubricating material and in particular propel it onto the upper set of bearings; the upper body portion of the rotating head is readily detachable from the lower sleeve portion which is normally welded to the well conductor pipe.

Adams, J.R.

1983-09-27T23:59:59.000Z

93

Spontaneous generation of rotation in tokamak plasmas  

SciTech Connect (OSTI)

Three different aspects of intrinsic rotation have been treated. i) A new, first principles model for intrinsic rotation [F.I. Parra, M. Barnes and P.J. Catto, Nucl. Fusion 51, 113001 (2011)] has been implemented in the gyrokinetic code GS2. The results obtained with the code are consistent with several experimental observations, namely the rotation peaking observed after an L-H transition, the rotation reversal observed in Ohmic plasmas, and the change in rotation that follows Lower Hybrid wave injection. ii) The model in [F.I. Parra, M. Barnes and P.J. Catto, Nucl. Fusion 51, 113001 (2011)] has several simplifying assumptions that seem to be satisfied in most tokamaks. To check the importance of these hypotheses, first principles equations that do not rely on these simplifying assumptions have been derived, and a version of these new equations has been implemented in GS2 as well. iii) A tokamak cross-section that drives large intrinsic rotation has been proposed for future large tokamaks. In large tokamaks, intrinsic rotation is expected to be very small unless some up-down asymmetry is introduced. The research conducted under this contract indicates that tilted ellipticity is the most efficient way to drive intrinsic rotation.

Parra Diaz, Felix [Oxford University] [Oxford University

2013-12-24T23:59:59.000Z

94

Experimental and analytical study of rotating cavitation  

SciTech Connect (OSTI)

This paper describes experimental and analytical results of rotating cavitation. There are four major sections in this paper. The first section presents the main characteristics of rotating cavitation which was found in the inducer test using a water tunnel. The second section describes the rotating cavitation which occurred in the development test of an LE-7 liquid oxygen pump for the H-II rocket. Also described in this section is how the rotating cavitation was suppressed. The rotating cavitation was the cause of both super synchronous shaft vibration and an unstable head coefficient curve. The third section presents how the theory of rotating cavitation was developed. The final section shows the measured cavitation compliance and mass flow gain factor of the LE-7 pump inducer for comparison of the experimental and analytical results of the rotating cavitation of the LE-7 pump inducer. Almost all the information presented in this paper has already been reported by Kamijo et al. (1977, 1980, 1993, 1993) and by Shimura (1993). In the present paper, the authors attempt to combine and give a clear overview of the experimental and analytical results described in the previous papers to systematically show their experience and findings on rotating cavitation.

Kamijo, Kenjiro; Shimura, Takashi; Tsujimoto, Yoshinobu [National Aerospace Lab., Miyagi (Japan). Kakuda Research Center

1994-12-31T23:59:59.000Z

95

Turbulent diffusion with rotation or magnetic fields  

E-Print Network [OSTI]

The turbulent diffusion tensor describing the evolution of the mean concentration of a passive scalar is investigated for forced turbulence either in the presence of rotation or a magnetic field. With rotation the Coriolis force causes a sideways deflection of the flux of mean concentration. Within the magnetohydrodynamics approximation there is no analogous effect from the magnetic field because the effects on the flow do not depend on the sign of the field. Both rotation and magnetic fields tend to suppress turbulent transport, but this suppression is weaker in the direction along the magnetic field. Turbulent transport along the rotation axis is not strongly affected by rotation, except on shorter length scales, i.e. when the scale of the variation of the mean field becomes comparable with the scale of the energy-carrying eddied.

Brandenburg, Axel; Vasil, Geoffrey M

2009-01-01T23:59:59.000Z

96

Models of soft rotators and the theory of a harmonic rotator  

E-Print Network [OSTI]

The states of a planar oscillator are separated to a vibrational mode, containing a zero-point energy, and a rotational mode without the zero-point energy, but having a conserved angular momentum. On the basis of the analysis of properties of models of rigid and semirigid rotators, the theory of soft rotators is formulated where the harmonic attractive force is balanced only by the centrifugal force. As examples a Coulomb rotator (the Bohr model) and a magneto-harmonic rotator (the Fock-Landau levels) are considered. Disappearance of the radial speed in the model of a magneto-harmonic rotator is taken as a defining property of a pure rotational motion in the harmonic potential. After the exception of energies of the magnetic and spin decompositions, specific to magnetic fields, one turns to a simple and general model of a planar harmonic rotator (circular oscillator without radial speed) where kinetic energy is reduced to the purely rotational energy. Energy levels of the harmonic rotator have the same frequency and are twice degenerate, the energy spectrum is equidistant. In the ground state there is no zero-point energy from rotational modes, and the zero-point energy of vibrational modes can be compensated by spin effects or symmetries of the system. In this case the operators of observables vanish the ground state, i.e. are "strongly" normally ordered. In a chain of harmonic rotators collective rotations around a common axis lead to transverse waves, at quantization of which there appear quasi-particles and holes carrying an angular momentum. In the chain SU(2) appears as a group of symmetry of a rotator.

Zahid Zakir

2012-12-12T23:59:59.000Z

97

Flow Split Venturi, Axially-Rotated Valve  

SciTech Connect (OSTI)

The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY); LaBelle, James (Murrieta, CA)

2000-02-22T23:59:59.000Z

98

Physics of Intrinsic Plasma Rotation Explained for the First...  

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

Physics of Intrinsic Plasma Rotation Explained for First Time Physics of Intrinsic Plasma Rotation Explained for First Time Key understanding for modeling future fusion reactors...

99

Analysis of Rotational Structure in the High-Resolution Infrared...  

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

Rotational Structure in the High-Resolution Infrared Spectrum and Assignment of Vibrational Fundamentals of Analysis of Rotational Structure in the High-Resolution Infrared...

100

Testing Oxygen Reduction Reaction Activity with the Rotating...  

Broader source: Energy.gov (indexed) [DOE]

Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique...

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Gravitational instability of slowly rotating isothermal spheres  

E-Print Network [OSTI]

We discuss the statistical mechanics of rotating self-gravitating systems by allowing properly for the conservation of angular momentum. We study analytically the case of slowly rotating isothermal spheres by expanding the solutions of the Boltzmann-Poisson equation in a series of Legendre polynomials, adapting the procedure introduced by Chandrasekhar (1933) for distorted polytropes. We show how the classical spiral of Lynden-Bell & Wood (1967) in the temperature-energy plane is deformed by rotation. We find that gravitational instability occurs sooner in the microcanonical ensemble and later in the canonical ensemble. According to standard turning point arguments, the onset of the collapse coincides with the minimum energy or minimum temperature state in the series of equilibria. Interestingly, it happens to be close to the point of maximum flattening. We determine analytically the generalization of the singular isothermal solution to the case of a slowly rotating configuration. We also consider slowly ...

Chavanis, P H

2002-01-01T23:59:59.000Z

102

Evolutionary optimization of rotational population transfer  

SciTech Connect (OSTI)

We present experimental and numerical studies on control of rotational population transfer of NO(J=1/2) molecules to higher rotational states. We are able to transfer 57% of the population to the J=5/2 state and 46% to J=9/2, in good agreement with quantum mechanical simulations. The optimal pulse shapes are composed of pulse sequences with delays corresponding to the beat frequencies of states on the rotational ladder. The evolutionary algorithm is limited by experimental constraints such as volume averaging and the finite laser intensity used, the latter to circumvent ionization. Without these constraints, near-perfect control (>98%) is possible. In addition, we show that downward control, moving molecules from high to low rotational states, is also possible.

Rouzee, Arnaud; Vrakking, Marc J. J. [FOM Institute for Atomic and Molecular Physics (AMOLF), Science Park 104, NL-1098 XG Amsterdam (Netherlands); Max Born Institut, Max Born Strasse 2A, D-12489, Berlin (Germany); Ghafur, Omair; Gijsbertsen, Arjan [FOM Institute for Atomic and Molecular Physics (AMOLF), Science Park 104, NL-1098 XG Amsterdam (Netherlands); Vidma, Konstantin; Meijer, Afric; Zande, Wim J. van der; Parker, David [Institute of Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, NL-6500 GL Nijmegen (Netherlands); Shir, Ofer M.; Baeck, Thomas [Leiden Institute of Advanced Computer Science (LIACS), Niels Bohrweg 1, NL-2333 CA Leiden (Netherlands)

2011-09-15T23:59:59.000Z

103

On rotationally driven meridional flows in stars  

E-Print Network [OSTI]

A quasi-steady state model of the consequences of rotation on the hydrodynamical structure of a stellar radiative zone is derived, by studying in particular the role of centrifugal and baroclinic driving of meridional motions in angular-momentum transport. This nonlinear problem is solved numerically assuming axisymmetry of the system, and within some limits, it is shown that there exist simple analytical solutions. The limit of slow rotation recovers Eddington-Sweet theory, whereas it is shown that in the limit of rapid rotation, the system settles into a geostrophic equilibrium. The behaviour of the system is found to be controlled by one parameter only, linked to the Prantl number, the stratification and the rotation rate of the star.

P. Garaud

2002-03-21T23:59:59.000Z

104

Galactic Rotation and Large Scale Structures  

E-Print Network [OSTI]

On the basis of a recent cosmological model, the puzzle of galactic rotational velocities at their edges is explained without invoking dark matter. A rationale for the existence of structures like galaxies and superclusters is also obtained.

B. G. Sidharth

1999-04-05T23:59:59.000Z

105

On obliquely magnetized and differentially rotating stars  

E-Print Network [OSTI]

We investigate the interaction of differential rotation and a misaligned magnetic field. The incompressible magnetohydrodynamic equations are solved numerically for a free-decay problem. In the kinematic limit, differential rotation annihilates the non-axisymmetric field on a timescale proportional to the cube root of magnetic Reynolds number ($Rm$), as predicted by R\\"adler. Nonlinearly, the outcome depends upon the initial energy in the non-axisymmetric part of the field. Sufficiently weak fields approach axisymmetry as in the kinematic limit; some differential rotation survives across magnetic surfaces, at least on intermediate timescales. Stronger fields enforce uniform rotation and remain non-axisymmetric. The initial field strength that divides these two regimes does not follow the scaling $Rm^{-1/3}$ predicted by quasi-kinematic arguments, perhaps because our $Rm$ is never sufficiently large or because of reconnection. We discuss the possible relevance of these results to tidal synchronization and tida...

Wei, Xing

2015-01-01T23:59:59.000Z

106

Consider Steam Turbine Drives for Rotating Equipment  

SciTech Connect (OSTI)

This revised ITP tip sheet on steam turbine drives for rotating equipment provides how-to advice for improving the system using low-cost, proven practices and technologies.

Not Available

2006-01-01T23:59:59.000Z

107

Spin Rotation of Formalism for Spin Tracking  

SciTech Connect (OSTI)

The problem of which coefficients are adequate to correctly represent the spin rotation in vector spin tracking for polarized proton and deuteron beams in synchrotrons is here re-examined in the light of recent discussions. The main aim of this note is to show where some previous erroneous results originated and how to code spin rotation in a tracking code. Some analysis of a recent experiment is presented that confirm the correctness of the assumptions.

Luccio,A.

2008-02-01T23:59:59.000Z

108

Critical frequency in nuclear chiral rotation  

E-Print Network [OSTI]

Within the cranked Skyrme-Hartree-Fock approach the self-consistent solutions have been obtained for planar and chiral rotational bands in 132La. It turns out that the chiral band cannot exist below some critical rotational frequency which in the present case equals omega=0.6MeV. The appearance of the critical frequency is explained in terms of a simple classical model of two gyroscopes coupled to a triaxial rigid body.

P. Olbratowski; J. Dobaczewski; J. Dudek

2002-11-25T23:59:59.000Z

109

Rotation in an exact hydro model  

E-Print Network [OSTI]

We study an exact and extended solution of the fluid dynamical model of heavy ion reactions, and estimate the rate of slowing down of the rotation due to the longitudinal and transverse expansion of the system. The initial state parameters of the model are set on the basis of a realistic 3+1D fluid dynamical calculation at TeV energies, where the rotation is enhanced by the build up of the Kelvin Helmholtz Instability in the flow.

Csernai, L P; Csorgo, T

2014-01-01T23:59:59.000Z

110

Rotation in an exact hydro model  

E-Print Network [OSTI]

We study an exact and extended solution of the fluid dynamical model of heavy ion reactions, and estimate the rate of slowing down of the rotation due to the longitudinal and transverse expansion of the system. The initial state parameters of the model are set on the basis of a realistic 3+1D fluid dynamical calculation at TeV energies, where the rotation is enhanced by the build up of the Kelvin Helmholtz Instability in the flow.

L. P. Csernai; D. J. Wang; T. Csorgo

2014-07-07T23:59:59.000Z

111

Vibrational Superposition States Without Rotating Wave Approximation  

E-Print Network [OSTI]

We propose a scheme to generate superpositions of coherent states for the vibrational motion of a laser cooled trapped-ion. It is based on the interaction with a standing wave making use of the counter-rotating terms, i.e. not applying the rotating wave approximation. We also show that the same scheme can be exploited for quantum state measurement, i.e. with the same scheme non-classical states may be reconstructed

Mancini, S; Tombesi, P

2000-01-01T23:59:59.000Z

112

Hydrogen atom in rotationally invariant noncommutative space  

E-Print Network [OSTI]

We consider the noncommutative algebra which is rotationally invariant. The hydrogen atom is studied in a rotationally invariant noncommutative space. We find the corrections to the energy levels of the hydrogen atom up to the second order in the parameter of noncommutativity. The upper bound of the parameter of noncommutativity is estimated on the basis of the experimental results for 1s-2s transition frequency.

Kh. P. Gnatenko; V. M. Tkachuk

2014-11-03T23:59:59.000Z

113

Split Venturi, Axially-Rotated Valve  

DOE Patents [OSTI]

The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane.

Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY)

2000-08-29T23:59:59.000Z

114

Internal Dynamics, Structure and Formation of Dwarf Elliptical Galaxies: II. Rotating Versus Non-Rotating Dwarfs  

E-Print Network [OSTI]

We present spatially-resolved internal kinematics and stellar chemical abundances for a sample of dwarf elliptical (dE) galaxies in the Virgo Cluster observed with Keck/ESI. We find that 4 out of 17 dEs have major axis rotation velocities consistent with rotational flattening, while the remaining dEs have no detectable major axis rotation. Despite this difference in internal kinematics, rotating and non-rotating dEs are remarkably similar in terms of their position in the Fundamental Plane, morphological structure, stellar populations, and local environment. We present evidence for faint underlying disks and/or weak substructure in a fraction of both rotating and non-rotating dEs, but a comparable number of counter-examples exist for both types which show no evidence of such structure. Absorption-line strengths were determined based on the Lick/IDS system (Hbeta, Mgb, Fe5270, Fe5335) for the central region of each galaxy. We find no difference in the line-strength indices, and hence stellar populations, between rotating and non-rotating dE galaxies. The best-fitting mean age and metallicity for our 17 dE sample are 5 Gyr and Fe/H = -0.3 dex, respectively, with rms spreads of 3 Gyr and 0.1 dex. The majority of dEs are consistent with solar alpha/Fe abundance ratios. By contrast, the stellar populations of classical elliptical galaxies are, on average, older, more metal rich, and alpha-enhanced relative to our dE sample. The local environments of both dEs types appear to be diverse in terms of their proximity to larger galaxies in real or velocity space within the Virgo Cluster. Thus, rotating and non-rotating dEs are remarkably similar in terms of their structure, stellar content, and local environments, presenting a significant challenge to theoretical models of their formation. (abridged)

M. Geha; P. Guhathakurta; R. van der Marel

2003-06-17T23:59:59.000Z

115

Gravitational instability of slowly rotating isothermal spheres  

E-Print Network [OSTI]

We discuss the statistical mechanics of rotating self-gravitating systems by allowing properly for the conservation of angular momentum. We study analytically the case of slowly rotating isothermal spheres by expanding the solutions of the Boltzmann-Poisson equation in a series of Legendre polynomials, adapting the procedure introduced by Chandrasekhar (1933) for distorted polytropes. We show how the classical spiral of Lynden-Bell & Wood (1967) in the temperature-energy plane is deformed by rotation. We find that gravitational instability occurs sooner in the microcanonical ensemble and later in the canonical ensemble. According to standard turning point arguments, the onset of the collapse coincides with the minimum energy or minimum temperature state in the series of equilibria. Interestingly, it happens to be close to the point of maximum flattening. We determine analytically the generalization of the singular isothermal solution to the case of a slowly rotating configuration. We also consider slowly rotating configurations of the self-gravitating Fermi gas at non zero temperature.

P. -H. Chavanis

2002-04-14T23:59:59.000Z

116

Heart - Shaped Nuclei: Condensation of Rotational Aligned Octupole Phonons  

E-Print Network [OSTI]

The strong octupole correlations in the mass region $A\\approx 226$ are interpreted as rotation-induced condensation of octupole phonons having their angular momentum aligned with the rotational axis. Discrete phonon energy and parity conservation generate oscillations of the energy difference between the lowest rotational bands with positive and negative parity. Anharmonicities tend to synchronize the the rotation of the condensate and the quadrupole shape of the nucleus forming a rotating heart shape.

S. Frauendorf

2007-10-24T23:59:59.000Z

117

Apparatus for rotating and reciprocating well pipe  

SciTech Connect (OSTI)

This patent describes an apparatus for simultaneously rotating and reciprocating well pipe, having an upper end, and mechanically utilizing a rotary table attached to a drilling rig, comprising: a rotating pipe clamp assembly having an irregular cross-sectional mid-member and clamp members for releasably gripping the well pipe connected to the ends of the mid-member for rotation therewith; a square block for fitting to the rotary table square and having a selected grooved interior configuration; a torque transmitting means fitted into the grooves having openings therethrough having the same irregular cross-section as the mid-member cross-section; and a torque limiting means connecting the torque transmitting means and the block for limiting torque applied through the well pipe via the clamp assembly and the torque transmitting means.

Davis, K.D.

1988-04-12T23:59:59.000Z

118

Position, rotation, and intensity invariant recognizing method  

DOE Patents [OSTI]

A method for recognizing the presence of a particular target in a field of view which is target position, rotation, and intensity invariant includes the preparing of a target-specific invariant filter from a combination of all eigen-modes of a pattern of the particular target. Coherent radiation from the field of view is then imaged into an optical correlator in which the invariant filter is located. The invariant filter is rotated in the frequency plane of the optical correlator in order to produce a constant-amplitude rotational response in a correlation output plane when the particular target is present in the field of view. Any constant response is thus detected in the output The U.S. Government has rights in this invention pursuant to Contract No. DE-AC04-76DP00789 between the U.S. Department of Energy and AT&T Technologies, Inc.

Ochoa, Ellen (Pleasanton, CA); Schils, George F. (San Ramon, CA); Sweeney, Donald W. (Alamo, CA)

1989-01-01T23:59:59.000Z

119

Magnetic rotation in {sup 112}In  

SciTech Connect (OSTI)

The high spin states of {sup 112}In have been investigated with in-beam {gamma}-ray spectroscopic methods using the {sup 110}Pd({sup 7}Li,5n){sup 112}In reaction at a beam energy of 50 MeV. A level scheme with three band structures has been established and their configurations are discussed. The positive-parity dipole band has been assigned as a magnetic rotation band. Particle-rotor model calculations have also been performed to interpret the rotational structures in {sup 112}In.

He, C. Y.; Li, X. Q.; Wu, X. G.; Liu, Y.; Pan, B.; Li, G. S.; Li, L. H.; Wang, Z. M. [China Institute of Atomic Energy, Beijing 102413 (China); Zhu, L. H. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); School of Science, Shenzhen University, Shenzhen 518060 (China); Qi, B.; Wang, S. Y. [School of Space Science and Physics, Shandong University at Weihai, Weihai 264209 (China); Li, Z. Y. [School of Physics and SK Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Xu, Q.; Wang, J. G.; Ding, H. B. [Department of Physics, Tsinghua University, Beijing 100084 (China); Zhai, J. [Department of Physics, Jilin University, Changchun 130023 (China)

2011-02-15T23:59:59.000Z

120

Internal Dynamics, Structure and Formation of Dwarf Elliptical Galaxies: II. Rotating Versus Non-Rotating Dwarfs  

E-Print Network [OSTI]

We present spatially-resolved internal kinematics and stellar chemical abundances for a sample of dwarf elliptical (dE) galaxies in the Virgo Cluster observed with Keck/ESI. We find that 4 out of 17 dEs have major axis rotation velocities consistent with rotational flattening, while the remaining dEs have no detectable major axis rotation. Despite this difference in internal kinematics, rotating and non-rotating dEs are remarkably similar in terms of their position in the Fundamental Plane, morphological structure, stellar populations, and local environment. We present evidence for faint underlying disks and/or weak substructure in a fraction of both rotating and non-rotating dEs, but a comparable number of counter-examples exist for both types which show no evidence of such structure. Absorption-line strengths were determined based on the Lick/IDS system (Hbeta, Mgb, Fe5270, Fe5335) for the central region of each galaxy. We find no difference in the line-strength indices, and hence stellar populations, betwe...

Geha, M; Van der Marel, R P

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

A theoretical analysis of rotating cavitation in inducers  

SciTech Connect (OSTI)

Rotating cavitation was analyzed using an actuator disk method. Quasi-steady pressure performance of the impeller, mass flow gain factor, and cavitation compliance of the cavity were taken into account. Three types of destabilizing modes were predicted: rotation cavitation propagating faster than the rotational speed of the impeller, rotating cavitation propagating in the direction opposite that of the impeller, and rotating stall propagating slower than the rotational speed of the impeller. It was shown that both types of rotating cavitation were caused by the positive mass flow gain factor, while the rotating stall was caused by the positive slope of the pressure performance. Stability and propagation velocity maps are presented for the two types of rotating cavitation in the mass flow gain factor-cavitation compliance place. The correlation between theoretical results and experimental observations is discussed.

Tsujimoto, Y.; Kamijo, K. (National Aerospace Lab., Miyagi, (Japan)); Yoshida, Y. (Osaka Univ., Toyonaka, (Japan). Engineering Science)

1993-03-01T23:59:59.000Z

122

Lateral displacement and rotational displacement sensor  

DOE Patents [OSTI]

A position measuring sensor formed from opposing sets of capacitor plates measures both rotational displacement and lateral displacement from the changes in capacitances as overlapping areas of capacitors change. Capacitances are measured by a measuring circuit. The measured capacitances are provided to a calculating circuit that performs calculations to obtain angular and lateral displacement from the capacitances measured by the measuring circuit.

Duden, Thomas

2014-04-22T23:59:59.000Z

123

Dual, rotating stripper rubber drilling head  

SciTech Connect (OSTI)

In a drilling head for a well bore through which a tool string of varying outside diameter is run, the drilling head sealing against fluid flow past the tool string to divert such fluid through a side outlet port, said drilling head including a housing having an axial passageway through which the tool string is run and a bearing assembly to facilitate rotation of the tool string within the axial passageway, the improved drilling head comprising: first and second stripper rubbers rotatably mounted within the drilling head housing in seating contact with the tool string, said stripper rubbers having substantially identical inner diameters through which the tool string extends, said first stripper rubber formed of an abrasive resistant material to divert fluid flow from the axial passageway of the housing to the side outlet port and said second stripper rubber formed on a sealingly resilient material which maintains sealing contact with the tool string extending there through preventing fluid flow past said tool string; said first stripper rubber being corrected to clamping means associated with the bearing assembly through a first drive ring such that said first stripper rubber rotates with the tool string; and said second stripper rubber is rotatably connected to said clamping means associated with the bearing assembly through a second drive ring, said first and second drive rings coaxially mounted within the housing whereby said first stripper rubber is positioned axially below said second stripper rubber in sealing contact with the tool string.

Bailey, T.F.; Campbell, J.E.

1993-05-25T23:59:59.000Z

124

Wave-particle Interactions In Rotating Mirrors  

SciTech Connect (OSTI)

Wave-particle interactions in E×B rotating plasmas feature an unusual effect: particles are diffused by waves in both potential energy and kinetic energy. This wave-particle interaction generalizes the alpha channeling effect, in which radio frequency waves are used to remove alpha particles collisionlessly at low energy. In rotating plasmas, the alpha particles may be removed at low energy through the loss cone, and the energy lost may be transferred to the radial electric field. This eliminates the need for electrodes in the mirror throat, which have presented serious technical issues in past rotating plasma devices. A particularly simple way to achieve this effect is to use a high azimuthal mode number perturbation on the magnetic field. Rotation can also be sustained by waves in plasmas without a kinetic energy source. This type of wave has been considered for plasma centrifuges used for isotope separation. Energy may also be transferred from the electric field to particles or waves, which may be useful for ion heating and energy generation.

Abraham J. Fetterman and Nathaniel J. Fisch

2011-01-11T23:59:59.000Z

125

Solar Dynamics, Rotation, Convection and Overshoot  

E-Print Network [OSTI]

We discuss recent observational, theoretical and modeling progress made in understanding the Sun's internal dynamics, including its rotation, meridional flow, convection and overshoot. Over the past few decades, substantial theoretical and observational effort has gone into appreciating these aspects of solar dynamics. A review of these observations, related helioseismic methodology and inference and computational results in relation to these problems is undertaken here.

Hanasoge, S; Roth, M; Schou, J; Schuessler, M; Thompson, M J

2015-01-01T23:59:59.000Z

126

Computational Methods for High-Dimensional Rotations  

E-Print Network [OSTI]

. To be useful, virtual rotations need to be under interactive user control, and they need to be animated. We therefore require projections not as static pictures but as movies under user control. Movies, however@maths.may.ie, http://www.maths.may.ie/staff/churley/churley.html 1 #12;1 Introduction Motion graphics for data

Buja, Andreas

127

Quantization of rotating linear dilaton black holes  

E-Print Network [OSTI]

In this paper, we firstly prove that the adiabatic invariant quantity, which is commonly used in the literature for quantizing the rotating black holes (BHs) is fallacious. We then show how its corrected form should be. The main purpose of this paper is to study the quantization of 4-dimensional rotating linear dilaton black hole (RLDBH) spacetime describing with an action, which emerges in the Einstein-Maxwell-Dilaton-Axion (EMDA) theory. The RLDBH spacetime has a non-asymptotically flat (NAF) geometry. They reduces to the linear dilaton black hole (LDBH) metric when vanishing its rotation parameter $a$. While studying its scalar perturbations, it is shown that the Schr\\"odinger-like wave equation around the event horizon reduces to a confluent hypergeometric differential equation. Then the associated complex frequencies of the quasinormal modes (QNMs) are computed. By using those QNMs in the true definition of the rotational adiabatic invariant quantity, we obtain the quantum spectra of entropy/area for the RLDBH. It is found out that both spectra are discrete and equidistant. Besides, we reveal that the quantum spectra do not depend on $a$ in spite of the QNMs are modulated by it.

I. Sakalli

2014-06-19T23:59:59.000Z

128

On rigidly rotating perfect fluid cylinders  

E-Print Network [OSTI]

The gravitational field of a rigidly rotating perfect fluid cylinder with gamma- law equation of state is found analytically. The solution has two parameters and is physically realistic for gamma in the interval (1.41,2]. Closed timelike curves always appear at large distances.

B. V. Ivanov

2002-05-07T23:59:59.000Z

129

Rigidly rotating cylinders of charged dust  

E-Print Network [OSTI]

The gravitational field of a rigidly rotating cylinder of charged dust is found analytically. The general and all regular solutions are divided into three classes. The acceleration and the vorticity of the dust are given, as well as the conditions for the appearance of closed timelike curves.

B. V. Ivanov

2002-07-02T23:59:59.000Z

130

Excitation system for rotating synchronous machines  

DOE Patents [OSTI]

A system for providing DC current to a rotating superconducting winding is provided. The system receives current feedback from the superconducting winding and determines an error signal based on the current feedback and a reference signal. The system determines a control signal corresponding to the error signal and provides a positive and negative superconducting winding excitation voltage based on the control signal.

Umans, Stephen D. (Belmont, MA); Driscoll, David J. (South Euclid, OH)

2002-01-01T23:59:59.000Z

131

Convective heat transfer in rotating, circular channels  

E-Print Network [OSTI]

Nusselt number values for flow in a rotating reference frame are obtained through computational fluid dynamic (CFD) analysis for Rossby numbers Ro ~1-4 and Reynolds numbers Re ~1,000-2,000. The heat-transfer model is first ...

Hogan, Brenna Elizabeth

2012-01-01T23:59:59.000Z

132

Extreme phase and rotated quadrature measurements  

E-Print Network [OSTI]

We determine the extreme points of the convex set of covariant phase observables. Such extremals describe the best phase parameter measurements of laser light - the best in the sense that they are free from classical randomness due to fluctuations in the measuring procedure. We also characterize extreme fuzzy rotated quadratures.

Juha-Pekka Pellonpää

2009-11-03T23:59:59.000Z

133

Film cooling effectiveness measurements on rotating and non-rotating turbine components  

E-Print Network [OSTI]

have significant effects on surface static pressure and film-cooling effectiveness. Same technique was applied to the rotating turbine blade leading edge region. Tests were conducted on the first stage rotor of a 3-stage axial turbine. The Reynolds...

Ahn, Jaeyong

2007-04-25T23:59:59.000Z

134

Three-dimensional rotating stall inception and effects of rotating tip clearance asymmetry in axial compressors  

E-Print Network [OSTI]

The effects of two types of flow nonuniformity on stall inception behavior were assessed with linearized stability analyses of two compressor flow models. Response to rotating tip clearance asymmetries induced by a whirling ...

Gordon, Kenneth A. (Kenneth Andrew), 1970-

1999-01-01T23:59:59.000Z

135

Discreteness and resolution effects in rapidly rotating turbulence  

E-Print Network [OSTI]

Rotating turbulence is characterized by the nondimensional Rossby number Ro, which is a measure of the strength of the Coriolis term relative to that of the nonlinear term. For rapid rotation (Ro?0), nonlinear interactions ...

Bourouiba, Lydia

136

Atmos. Meas. Tech., 3, 13331349, 2010 www.atmos-meas-tech.net/3/1333/2010/  

E-Print Network [OSTI]

of Energy (DOE) Atmospheric Ra- diation Measurement (ARM) Southern Great Plains site. A detailed case study-filter Rotating Shadowband Radiometers (MFRSRs). The interpolation algorithm that is used to project MFRSR point measurements onto the air- craft flight tracks is tested using AOD derived from NASA Langley High Spectral

137

Quantum Mechanics of a Rotating Billiard  

E-Print Network [OSTI]

Integrability of a square billiard is spontaneously broken as it rotates about one of its corners. The system becomes quasi-integrable where the invariant tori are broken with respect to a certain parameter, $\\lambda = 2E/\\omega^{2}$ where E is the energy of the particle inside the billiard and $\\omega$ is the angular frequency of rotation of billiard. We study the system classically and quantum mechanically in view of obtaining a correspondence in the two descriptions. Classical phase space in Poincar\\'{e} surface of section shows transition from regular to chaotic motion as the parameter $\\lambda$ is decreased. In the Quantum counterpart, the spectral statistics shows a transition from Poisson to Wigner distribution as the system turns chaotic with decrease in $\\lambda$. The wavefunction statistics however show breakdown of time-reversal symmetry as $\\lambda$ decreases.

Nandan Jha; Sudhir R. Jain

2014-06-12T23:59:59.000Z

138

Chiral meta-atoms rotated by light  

SciTech Connect (OSTI)

We study the opto-mechanical properties of coupled chiral meta-atoms based on a pair of twisted split-ring resonators. By using a simple analytical model in conjunction with the Maxwell stress tensor, we capture insight into the mechanism and find that this structure can be used as a general prototype of subwavelength light-driven actuators over a wide range of frequencies. This coupled structure can provide a strong and tunable torque, and can support different opto-mechanical modes, including uniform rotation, periodically variable rotation and damped oscillations. Our results suggest that chiral meta-atoms are good candidates for creating sub-wavelength motors or wrenches controlled by light.

Liu Mingkai; Powell, David A.; Shadrivov, Ilya V. [Nonlinear Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

2012-07-16T23:59:59.000Z

139

Rotation and anisotropy of galaxies revisited  

E-Print Network [OSTI]

The use of the tensor virial theorem (TVT) as a diagnostic of anisotropic velocity distributions in galaxies is revisited. The TVT provides a rigorous global link between velocity anisotropy, rotation and shape, but the quantities appearing in it are not easily estimated observationally. Traditionally use has been made of a centrally averaged velocity dispersion and the peak rotation velocity. Although this procedure cannot be rigorously justified, tests on model galaxies show that it works surprisingly well. With the advent of integral-field spectroscopy it is now possible to establish a rigorous connection between the TVT and observations. The TVT is reformulated in terms of sky-averages, and the new formulation is tested on model galaxies.

James Binney

2005-04-18T23:59:59.000Z

140

Measurement of turbulent wind velocities using a rotating boom apparatus  

SciTech Connect (OSTI)

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

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

1984-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Accelerating and rotating black holes J. B. Griffiths1  

E-Print Network [OSTI]

Accelerating and rotating black holes J. B. Griffiths1 and J. Podolsk´y2 1Department Abstract An exact solution of Einstein's equations which represents a pair of accelerating and rotating which explicitly contains the known special cases for either rotating or accelerating black holes

142

Spin-stabilized magnetic levitation without vertical axis of rotation  

DOE Patents [OSTI]

The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.

Romero, Louis (Albuquerque, NM); Christenson, Todd (Albuquerque, NM); Aaronson, Gene (Albuquerque, NM)

2009-06-09T23:59:59.000Z

143

A Novel Membrane Finite Element with Drilling Rotations  

E-Print Network [OSTI]

A Novel Membrane Finite Element with Drilling Rotations Reijo Kouhia 1 Abstract. A new low order interpolation is used for the drill rotation #12;eld. Both triangular and quadrilateral elements are considered of freedom. 1 INTRODUCTION In-plane rotational degrees of freedom, \\drilling de- grees of freedom

Kouhia, Reijo

144

3D discrete rotations using hinge angles Yohan Thibaulta,  

E-Print Network [OSTI]

3D discrete rotations using hinge angles Yohan Thibaulta, , Akihiro Sugimotob , Yukiko Kenmochia a of Informatics, Japan Abstract In this paper, we study 3D rotations on grid points computed by using only integers. For that purpose, we investigate the intersection between the 3D half- grid and the rotation

Paris-Sud XI, Université de

145

Counter-rotating Kerr manifolds separated by a fluid shell  

E-Print Network [OSTI]

We describe a spheroidal fluid shell between two Kerr vacuum regions which have opposite rotation parameters. The shell has a stiff equation of state and a heat flow vector related to the rotational Killing current. The shell description is useful in exploring the significance of counter-rotation in Kerr metric matches.

J. P. Krisch; E. N. Glass

2009-08-13T23:59:59.000Z

146

Evaluating ecosystem processes in willow short rotation coppice bioenergy plantations  

E-Print Network [OSTI]

Evaluating ecosystem processes in willow short rotation coppice bioenergy plantations R E B E C C and lit- ter decomposition varied between Short Rotation Coppice (SRC) willow bioenergy plantations., 2009). Willow (Salix spp) short rotation coppice (SRC) is one of the most widely planted second

147

Galaxy rotation curves in de Sitter space  

E-Print Network [OSTI]

Dark energy inferred from the observed negative deceleration parameter introduces a small mass of the graviton, that satisfies the Higuchi stability condition. It implies an infra-red modification of gravitation that produces Milgrom's inverse distance law of gravitational attraction in excellent agreement with the observed galaxy rotation curves. We conclude that dark matter is present cosmologically with no need for local clustering in galaxies.

Maurice H. P. M. van Putten

2015-01-27T23:59:59.000Z

148

Rotating sample holder at low temperature  

SciTech Connect (OSTI)

A low temperature rotary device (cryoturbine) for use in extended x-ray-absorption fine structure measurements in fluorescence mode has been designed and manufactured. The instrument works at a temperature close to liquid Nitrogen and can reach frequencies up to 100 Hz with good stability. The rotation speed is measured with a light-emitting diode driven in stroboscopic mode by a simple electronic circuit.

Pasternak, Sebastien; Perrin, Florian; Ciatto, Gianluca; Palancher, Herve; Steinmann, Ricardo [European Synchrotron Radiation Facility, 38043 Grenoble (France)

2007-07-15T23:59:59.000Z

149

Deployment of a New Shortwave Spectroradiometer (SWS) at the SGP  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phasesData Files DataADVANCESDepartmentDepartmentalDeployment of a New

150

Pulse Analysis Spectroradiometer System (PASS) Software - Energy Innovation  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedlesAdvancedJanuary 13, 2011Portal Energy Analysis Energy

151

Ghost condensate model of flat rotation curves  

E-Print Network [OSTI]

An effective action of ghost condensate with higher derivatives creates a source of gravity and mimics a dark matter in spiral galaxies. We present a spherically symmetric static solution of Einstein--Hilbert equations with the ghost condensate at large distances, where flat rotation curves are reproduced in leading order over small ratio of two energy scales characterizing constant temporal and spatial derivatives of ghost field: $\\mu_*^2$ and $\\mu_\\star^2$, respectively, with a hierarchy $\\mu_\\star\\ll \\mu_*$. We assume that a mechanism of hierarchy is provided by a global monopole in the center of galaxy. An estimate based on the solution and observed velocities of rotations in the asymptotic region of flatness, gives $\\mu_*\\sim 10^{19}$ GeV and the monopole scale in a GUT range $\\mu_\\star\\sim 10^{16}$ GeV, while a velocity of rotation $v_0$ is determined by the ratio: $ \\sqrt{2} v_0^2= \\mu_\\star^2/\\mu_*^2$. A critical acceleration is introduced and naturally evaluated of the order of Hubble rate, that represents the Milgrom's acceleration.

V. V. Kiselev

2005-07-29T23:59:59.000Z

152

Covariant density functional theory for antimagnetic rotation  

E-Print Network [OSTI]

Following the previous letter on the first microscopic description of the antimagnetic rotation (AMR) in 105Cd, a systematic investigation and detailed analysis for the AMR band in the frame-work of tilted axis cranking (TAC) model based on covariant density functional theory are carried out. After performing the microscopic and self-consistentTAC calculations with an given density functional, the configuration for the observed AMR band in 105Cd is obtained from the single-particle Routhians. With the configuration thus obtained, the tilt angle for a given rotational frequency is determined self-consistently by minimizing the total Routhian with respect to the tilt angle. In such a way, the energy spectrum, total angular momenta, kinetic and dynamic moments of inertia, and the B(E2) values for the AMR band in 105Cd are calculated. Good agreement with the data is found. By investigating microscopically the contributions from neutrons and protons to the total angular momentum, the "two-shears-like" mechanism in the AMR band is clearly illus-trated. Finally, the currents leading to time-odd mean fields in the Dirac equation are presented and discussed in detail. It is found that they are essentially determined by the valence particles and/or holes. Their spatial distribution and size depend onthe specific single-particle orbitals and the rotational frequency.

P. W. Zhao; J. Peng; H. Z. Liang; P. Ring; J. Meng

2012-05-04T23:59:59.000Z

153

Lithium depletion and the rotational history of exoplanet host stars  

E-Print Network [OSTI]

Israelian et al. (2004) reported that exoplanet host stars are lithium depleted compared to solar-type stars without detected massive planets, a result recently confirmed by Gonzalez (2008). We investigate whether enhanced lithium depletion in exoplanet host stars may result from their rotational history. We have developed rotational evolution models for slow and fast solar-type rotators from the pre-main sequence (PMS) to the age of the Sun and compare them to the distribution of rotational periods observed for solar-type stars between 1 Myr and 5 Gyr. We show that slow rotators develop a high degree of differential rotation between the radiative core and the convective envelope, while fast rotators evolve with little core-envelope decoupling. We suggest that strong differential rotation at the base of the convective envelope is responsible for enhanced lithium depletion in slow rotators. We conclude that lithium-depleted exoplanet host stars were slow rotators on the zero-age main sequence (ZAMS) and argue that slow rotation results from a long lasting star-disk interaction during the PMS. Altogether, this suggests that long-lived disks (> 5 Myr) may be a necessary condition for massive planet formation/migration.

Jerome Bouvier

2008-09-03T23:59:59.000Z

154

Rotation of the solar convection zone from helioseismology  

E-Print Network [OSTI]

Helioseismology has provided very detailed inferences about rotation of the solar interior. Within the convection zone the rotation rate roughly shares the latitudinal variation seen in the surface differential rotation. The transition to the nearly uniformly rotating radiative interior takes place in a narrow tachocline, which is likely important to the operation of the solar magnetic cycle.The convection-zone rotation displays zonal flows, regions of slightly more rapid and slow rotation, extending over much of the depth of the convection zone and converging towards the equator as the solar cycle progresses. In addition, there is some evidence for a quasi-periodic variation in rotation, with a period of around 1.3 yr, at the equator near the bottom of the convection zone.

J. Christensen-Dalsgaard

2006-10-31T23:59:59.000Z

155

Isorotation and differential rotation in a magnetic mirror with imposed E Multiplication-Sign B rotation  

SciTech Connect (OSTI)

Doppler spectroscopy of helium impurities in the Maryland Centrifugal Experiment reveals the simultaneous existence of isorotating and differentially rotating magnetic surfaces. Differential rotation occurs at the innermost surfaces and is conjectured to cause plasma voltage oscillations of hundreds of kilohertz by periodically changing the current path inductance. High-speed images show the periodic expulsion of plasma near the mirror ends at the same frequencies. In spite of this, the critical ionization velocity limit is exceeded, with respect to the vacuum field definition, for at least 0.5 ms.

Romero-Talamas, C. A.; Elton, R. C.; Young, W. C.; Reid, R.; Ellis, R. F. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)

2012-07-15T23:59:59.000Z

156

Algebraically general, gravito-electric rotating dust  

E-Print Network [OSTI]

The class of gravito-electric, algebraically general, rotating `silent' dust space-times is studied. The main invariant properties are deduced. The number $t_0$ of functionally independent zero-order Riemann invariants satisfies $1\\leq t_0\\leq 2$ and special attention is given to the subclass $t_0=1$. Whereas there are no $\\Lambda$-term limits comprised in the class, the limit for vanishing vorticity leads to two previously derived irrotational dust families with $\\Lambda>0$, and the shear-free limit is the G\\"{o}del universe.

Lode Wylleman

2008-06-17T23:59:59.000Z

157

Collisional Penrose Process in Rotating Wormhole Spacetime  

E-Print Network [OSTI]

In a collisional Penrose process, two particles coming from the asymptotically flat region collide in the ergosphere of a compact object. The collision produces two new particles, one with positive energy and one with negative energy. When the particle with positive energy escapes to infinity, the process extracts energy from the compact object. In this paper, we study the collisional Penrose process in a rotating wormhole spacetime. We consider the simple case of a head-on collision at the throat of a Teo wormhole. We find that the process of energy extraction from a Teo wormhole can be substantially more efficient than the collisional Penrose process in the Kerr black hole spacetime.

Naoki Tsukamoto; Cosimo Bambi

2015-03-22T23:59:59.000Z

158

Rotating electric machine with fluid supported parts  

DOE Patents [OSTI]

A rotating electric machine in which the armature winding thereof and other parts are supported by a liquid to withstand the mechanical stresses applied during transient overloads and the like. In particular, a narrow gap is provided between the armature winding and the stator which supports it and this gap is filled with an externally pressurized viscous liquid. The liquid is externally pressurized sufficiently to balance the static loads on the armature winding. Transient mechanical loads which deform the armature winding alter the gap dimensions and thereby additionally pressurize the viscous liquid to oppose the armature winding deformation and more nearly uniformly to distribute the resulting mechanical stresses.

Smith, Jr., Joseph L. (Concord, MA); Kirtley, Jr., James L. (Brookline, MA)

1981-01-01T23:59:59.000Z

159

Paramagnetic alignment of thermally rotating dust  

E-Print Network [OSTI]

Paramagnetic alignment of thermally rotating oblate dust grains is studied analytically for finite ratios of grain to gas temperatures. For such ratios, the alignment of angular momentum J in respect to the grain axis of maximal inertia is only partial. We treat the alignment of J using perturbative methods and disentangle the problem of J alignment in grain body axes from that of J alignment in respect to magnetic field. This enables us to find the alignment of grain axes to magnetic field and thus relate our theory to polarimetric observations.Our present results are applicable to the alignment of both paramagnetic and superparamagnetic grains.

A. Lazarian

1997-02-16T23:59:59.000Z

160

Hidden Rotational Symmetries in Magnetic Domain Patterns  

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

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Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" from the National Library of EnergyBeta (NLEBeta).
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161

Hidden Rotational Symmetries in Magnetic Domain Patterns  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun with Bigfront.jpgcommunity200cellHeatExperiment. |Hidden Rotational

162

Hidden Rotational Symmetries in Magnetic Domain Patterns  

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

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163

Hidden Rotational Symmetries in Magnetic Domain Patterns  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun with Bigfront.jpgcommunity200cellHeatExperiment. |HiddenHidden Rotational

164

Collisional Penrose Process in Rotating Wormhole Spacetime  

E-Print Network [OSTI]

In a collisional Penrose process, two particles coming from the asymptotically flat region collide in the ergosphere of a compact object. The collision produces two new particles, one with positive energy and one with negative energy. When the particle with positive energy escapes to infinity, the process extracts energy from the compact object. In this paper, we study the collisional Penrose process in a rotating wormhole spacetime. We consider the simple case of a head-on collision at the throat of a Teo wormhole. We find that the process of energy extraction from a Teo wormhole can be substantially more efficient than the collisional Penrose process in the Kerr black hole spacetime.

Tsukamoto, Naoki

2015-01-01T23:59:59.000Z

165

Measuring deflections in a rotating shaft  

E-Print Network [OSTI]

The Wheatstone Bridge circuit made of the strain gages on the transducer. The calibration configuration and equipment. . The output signal - displacement curve. . 20 28 Decay curve of the free oscillations of the trans- ducer 30 12 13 14 The damping... of the rotating Wheatstone Bridge to a stat1onary conductor that leads into the final readout equipment. These slip rings can be constructed 1n several different manners, but in order for them to be effective in dynamic s1tuations, they are quite expensive...

Bailey, Edmond Ira

1968-01-01T23:59:59.000Z

166

Advanced Rotating Heat Exchangers | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

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167

Short-Rotation Woody Biomass Sustainability  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |Energy Usage » SearchEnergyDepartment of EnergyLight-Duty DieselReview Short-Rotation

168

Dynamics and Statistical Mechanics of Rotating and non-Rotating Vortical Flows  

SciTech Connect (OSTI)

Three projects were analyzed with the overall aim of developing a computational/analytical model for estimating values of the energy, angular momentum, enstrophy and total variation of fluid height at phase transitions between disordered and self-organized flow states in planetary atmospheres. It is believed that these transitions in equilibrium statistical mechanics models play a role in the construction of large-scale, stable structures including super-rotation in the Venusian atmosphere and the formation of the Great Red Spot on Jupiter. Exact solutions of the spherical energy-enstrophy models for rotating planetary atmospheres by Kac's method of steepest descent predicted phase transitions to super-rotating solid-body flows at high energy to enstrophy ratio for all planetary spins and to sub-rotating modes if the planetary spin is large enough. These canonical statistical ensembles are well-defined for the long-range energy interactions that arise from 2D fluid flows on compact oriented manifolds such as the surface of the sphere and torus. This is because in Fourier space available through Hodge theory, the energy terms are exactly diagonalizable and hence has zero range, leading to well-defined heat baths.

Lim, Chjan [RPI] [RPI

2013-12-18T23:59:59.000Z

169

Mechanical alignment of suprathermally rotating grains  

E-Print Network [OSTI]

It is shown that mechanical alignment of grains can be efficient for grains rotating suprathermally, i.e. with kinetic energy substantially exceeding $k$ (the Boltzmann constant) over any temperature in the system. The paper studies suprathermal rotation caused by H$_{2}$ formation and the alignment that takes place due to crossover events. Gaseous bombardment in the course of a crossover as well as both gaseous friction and poisoning of active sites are shown to produce alignment. The first type of alignment happens due to the angular momentum deposited by a corpuscular flux with a grain, the second is caused by the change of the mean time back to crossover due to the interaction with a gaseous flux. We show that the two processes act as to decrease the grain cross section in respect to the flux and we find the Rayleigh reduction factor for the joint action of the two processes as well as the range of applicability of each of the processes. Our study indicates that mechanical alignment can be more widely spread than it is generally accepted.

A. Lazarian

1995-05-01T23:59:59.000Z

170

Rotation Curve Measurement using Cross-Correlation  

E-Print Network [OSTI]

Longslit spectroscopy is entering an era of increased spatial and spectral resolution and increased sample size. Improved instruments reveal complex velocity structure that cannot be described with a one-dimensional rotation curve, yet samples are too numerous to examine each galaxy in detail. Therefore, one goal of rotation curve measurement techniques is to flag cases in which the kinematic structure of the galaxy is more complex than a single-valued curve. We examine cross-correlation as a technique that is easily automated and works for low signal-to-noise spectra. We show that the technique yields well-defined errors which increase when the simple spectral model (template) is a poor match to the data, flagging those cases for later inspection. We compare the technique to the more traditional, parametric technique of simultaneous emission line fitting. When the line profile at a single slit position is non-Gaussian, the techniques disagree. For our model spectra with two well-separated velocity components, assigned velocities from the two techniques differ by up to ~52% of the velocity separation of the model components. However, careful use of the error statistics for either technique allows one to flag these non-Gaussian spectra.

Elizabeth J. Barton; Sheila J. Kannappan; Michael J. Kurtz; Margaret J. Geller

2000-06-20T23:59:59.000Z

171

Rotational actuator of motor based on carbon nanotubes  

DOE Patents [OSTI]

A rotational actuator/motor based on rotation of a carbon nanotube is disclosed. The carbon nanotube is provided with a rotor plate attached to an outer wall, which moves relative to an inner wall of the nanotube. After deposit of a nanotube on a silicon chip substrate, the entire structure may be fabricated by lithography using selected techniques adapted from silicon manufacturing technology. The structures to be fabricated may comprise a multiwall carbon nanotube (MWNT), two in plane stators S1, S2 and a gate stator S3 buried beneath the substrate surface. The MWNT is suspended between two anchor pads and comprises a rotator attached to an outer wall and arranged to move in response to electromagnetic inputs. The substrate is etched away to allow the rotor to freely rotate. Rotation may be either in a reciprocal or fully rotatable manner.

Zettl, Alexander K. (Kensington, CA); Fennimore, Adam M. (Berkeley, CA); Yuzvinsky, Thomas D. (Berkeley, CA)

2008-11-18T23:59:59.000Z

172

Generation of Closed Timelike Curves with Rotating Superconductors  

E-Print Network [OSTI]

The spacetime metric around a rotating SuperConductive Ring (SCR) is deduced from the gravitomagnetic London moment in rotating superconductors. It is shown that theoretically it is possible to generate Closed Timelike Curves (CTC) with rotating SCRs. The possibility to use these CTC's to travel in time as initially idealized by G\\"{o}del is investigated. It is shown however, that from a technology and experimental point of view these ideas are impossible to implement in the present context.

Clovis Jacinto de Matos

2007-01-19T23:59:59.000Z

173

Forming rotated SAR images by real-time motion compensation.  

SciTech Connect (OSTI)

Proper waveform parameter selection allows collecting Synthetic Aperture Radar (SAR) phase history data on a rotated grid in the Fourier Space of the scene being imaged. Subsequent image formation preserves the rotated geometry to allow SAR images to be formed at arbitrary rotation angles without the use of computationally expensive interpolation or resampling operations. This should be useful where control of image orientation is desired such as generating squinted stripmaps and VideoSAR applications, among others.

Doerry, Armin Walter

2012-12-01T23:59:59.000Z

174

Laser induced rotation of trapped chiral and achiral nematic droplets  

E-Print Network [OSTI]

We study the response of optically trapped achiral and chiralised nematic liquid crystal droplets to linear as well as circular polarised light. We find that there is internal dissipation in rotating achiral nematic droplets trapped in glycerine. We also demonstrate that some chiralised droplets rotate under linearly polarised light. The best fit to our data on chiralised droplets indicates that rotational frequency of these droplets with radius R is approximately proportional to1/R^2, rather than to 1/R^3.

Marjan Mosallaeipour; Yashodhan Hatwalne; N. V. Madhusudana; Sharath Ananthamurthy

2010-02-05T23:59:59.000Z

175

High-Performance Refrigerator Using Novel Rotating Heat Exchanger...  

Broader source: Energy.gov (indexed) [DOE]

pumps have the potentially to reduce energy costs and refrigerant charge in a compact space. Rotating heat exchangers installed in appliances and heat pumps have the potentially...

176

arthroscopically repaired rotator: Topics by E-print Network  

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

rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when...

177

Abstract: Development and Deployment of a Short Rotation Woody...  

Energy Savers [EERE]

Development and Deployment of a Short Rotation Woody Crops Harvesting System Based on a Case New Holland Forage Harvester and SRC Woody Crop Header Abstract: Development and...

178

INTERNAL-CYCLE VARIATION OF SOLAR DIFFERENTIAL ROTATION  

SciTech Connect (OSTI)

The latitudinal distributions of the yearly mean rotation rates measured by Suzuki in 1998 and 2012 and Pulkkinen and Tuominen in 1998 are utilized to investigate internal-cycle variation of solar differential rotation. The rotation rate at the solar equator seems to have decreased since cycle 10 onward. The coefficient B of solar differential rotation, which represents the latitudinal gradient of rotation, is found to be smaller in the several years after the minimum of a solar cycle than in the several years after the maximum time of the cycle, and it peaks several years after the maximum time of the solar cycle. The internal-cycle variation of the solar rotation rates looks similar in profile to that of the coefficient B. A new explanation is proposed to address such a solar-cycle-related variation of the solar rotation rates. Weak magnetic fields may more effectively reflect differentiation at low latitudes with high rotation rates than at high latitudes with low rotation rates, and strong magnetic fields may more effectively repress differentiation at relatively low latitudes than at high latitudes. The internal-cycle variation is inferred as the result of both the latitudinal migration of the surface torsional pattern and the repression of strong magnetic activity in differentiation.

Li, K. J.; Xie, J. L.; Shi, X. J., E-mail: lkj@ynao.ac.cn [National Astronomical Observatories/Yunnan Observatory, CAS, Kunming 650011 (China)

2013-06-01T23:59:59.000Z

179

Cooling for a rotating anode X-ray tube  

DOE Patents [OSTI]

A method and apparatus for cooling a rotating anode X-ray tube. An electromagnetic motor is provided to rotate an X-ray anode with cooling passages in the anode. These cooling passages are coupled to a cooling structure located adjacent the electromagnetic motor. A liquid metal fills the passages of the cooling structure and electrical power is provided to the motor to rotate the anode and generate a rotating magnetic field which moves the liquid metal through the cooling passages and cooling structure.

Smither, Robert K. (Hinsdale, IL)

1998-01-01T23:59:59.000Z

180

Counter-Rotating Tandem Motor Drilling System  

SciTech Connect (OSTI)

Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively compared to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger than that of slim holes. As a result, the research team decided to complete the project, document the tested designs and seek further support for the concept outside of the DOE.

Kent Perry

2009-04-30T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Retrieval of Areal-averaged Spectral Surface Albedo from Transmission Data Alone: Computationally Simple and Fast Approach  

SciTech Connect (OSTI)

We introduce and evaluate a simple retrieval of areal-averaged surface albedo using ground-based measurements of atmospheric transmission alone at five wavelengths (415, 500, 615, 673 and 870nm), under fully overcast conditions. Our retrieval is based on a one-line semi-analytical equation and widely accepted assumptions regarding the weak spectral dependence of cloud optical properties, such as cloud optical depth and asymmetry parameter, in the visible and near-infrared spectral range. To illustrate the performance of our retrieval, we use as input measurements of spectral atmospheric transmission from Multi-Filter Rotating Shadowband Radiometer (MFRSR). These MFRSR data are collected at two well-established continental sites in the United States supported by the U.S. Department of Energy’s (DOE’s) Atmospheric Radiation Measurement (ARM) Program and National Oceanic and Atmospheric Administration (NOAA). The areal-averaged albedos obtained from the MFRSR are compared with collocated and coincident Moderate Resolution Imaging Spectroradiometer (MODIS) white-sky albedo. In particular, these comparisons are made at four MFRSR wavelengths (500, 615, 673 and 870nm) and for four seasons (winter, spring, summer and fall) at the ARM site using multi-year (2008-2013) MFRSR and MODIS data. Good agreement, on average, for these wavelengths results in small values (?0.01) of the corresponding root mean square errors (RMSEs) for these two sites. The obtained RMSEs are comparable with those obtained previously for the shortwave albedos (MODIS-derived versus tower-measured) for these sites during growing seasons. We also demonstrate good agreement between tower-based daily-averaged surface albedos measured for “nearby” overcast and non-overcast days. Thus, our retrieval originally developed for overcast conditions likely can be extended for non-overcast days by interpolating between overcast retrievals.

Kassianov, Evgueni I.; Barnard, James C.; Flynn, Connor J.; Riihimaki, Laura D.; Michalsky, Joseph; Hodges, G. B.

2014-10-25T23:59:59.000Z

182

Bunch Profiling Using a Rotating Mask  

SciTech Connect (OSTI)

The current method for measuring profiles of proton bunches in accelerators is severely lacking. One must dedicate a great deal of time and expensive equipment to achieve meaningful results. A new method to complete this task uses a rotating mask with slots of three different orientations to collect this data. By scanning over the beam in three different directions, a complete profile for each bunch is built in just seconds, compared to the hours necessary for the previous method. This design was successfully tested using synchrotron radiation emitted by SPEAR3. The profile of the beam was measured in each of the three desired directions. Due to scheduled beam maintenance, only one set of data was completed and more are necessary to solve any remaining issues. The data collected was processed and all of the RMS sizes along the major and minor axes, as well as the tilt of the beam ellipse were measured.

Miller, Mitchell; /SLAC /IIT, Chicago

2012-08-24T23:59:59.000Z

183

Relativistic MHD Winds from Rotating Neutron Stars  

E-Print Network [OSTI]

We solve the time-dependent dynamics of axisymmetric, general relativistic MHD winds from rotating neutron stars. The mass loss rate is obtained self consistently as a solution of the MHD equations, subject to a finite thermal pressure at the stellar surface. Conditions are chosen to be representative of the neutrino driven phase in newly born magnetars, which have been considered as a possible engine for GRBs. We compute the angular momentum and energy losses as a function of $\\sigma$ and compare them with the analytic expectation from the classical theory of pulsar winds. We observe the convergence to the force-free limit in the energy loss and we study the evolution of the closed zone for increasing magnetization. Results also show that the dipolar magnetic field and the presence of a closed zone do not modify significantly the acceleration and collimation properties of the wind.

N. Bucciantini; T. A. Thompson; J. Arons; E. Quataert

2006-12-22T23:59:59.000Z

184

Rotational band properties in {sup 165}Er  

SciTech Connect (OSTI)

High-spin states in {sup 165}Er have been studied experimentally using the {sup 160}Gd({sup 9}Be, 4n) reaction at beam energies of 42 and 45 MeV. The previously known bands based on the 5/2{sup +}[642], 5/2{sup -}[523], and 11/2{sup -}[505] configurations are extended to (49/2{sup +}), (45/2{sup -}), and (31/2{sup -}) states, respectively. The rotational bands in {sup 165}Er generally show gradual alignment processes, indicating strong band interactions associated with the i{sub 13/2} neutron alignments. The band properties are compared with those in the neighboring nuclei and discussed within the framework of the cranked shell model.

Wang, S. T. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhou, X. H.; Zhang, Y. H.; Zheng, Y.; Liu, M. L.; Chen, L.; Zhang, N. T.; Hua, W.; Guo, S.; Qiang, Y. H.; Li, G. S.; Ding, B. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Shi, Y.; Xu, F. R. [School of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China)

2011-07-15T23:59:59.000Z

185

MULTI-DIMENSIONAL SIMULATIONS OF ROTATING PAIR-INSTABILITY SUPERNOVAE  

SciTech Connect (OSTI)

We study the effects of rotation on the dynamics, energetics, and {sup 56}Ni production of pair instability supernova (PISN) explosions by performing rotating two-dimensional ({sup 2}.5D{sup )} hydrodynamics simulations. We calculate the evolution of eight low-metallicity (Z = 10{sup –3}, 10{sup –4} Z{sub ?}) massive (135-245 M{sub ?}) PISN progenitors with initial surface rotational velocities of 50% of the critical Keplerian value using the stellar evolution code MESA. We allow for both the inclusion and the omission of the effects of magnetic fields in the angular momentum transport and in chemical mixing, resulting in slowly rotating and rapidly rotating final carbon-oxygen cores, respectively. Increased rotation for carbon-oxygen cores of the same mass and chemical stratification leads to less energetic PISN explosions that produce smaller amounts of {sup 56}Ni due to the effect of the angular momentum barrier that develops and slows the dynamical collapse. We find a non-monotonic dependence of {sup 56}Ni production on rotational velocity in situations when smoother composition gradients form at the outer edge of the rotating cores. In these cases, the PISN energetics are determined by the competition of two factors: the extent of chemical mixing in the outer layers of the core due to the effects of rotation in the progenitor evolution and the development of angular momentum support against collapse. Our 2.5D PISN simulations with rotation are the first presented in the literature. They reveal hydrodynamic instabilities in several regions of the exploding star and increased explosion asymmetries with higher core rotational velocity.

Chatzopoulos, E.; Wheeler, J. Craig [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Couch, Sean M., E-mail: manolis@astro.as.utexas.edu [Department of Astronomy and Astrophysics, Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States)

2013-10-20T23:59:59.000Z

186

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR  

E-Print Network [OSTI]

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR By SCOTT RUSSELL WAITUKAITIS A Thesis Submitted: #12;Abstract I describe a study of Faraday rotation in a hot lithium vapor. I begin by dis- cussing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 The Lithium Oven and Solenoid . . . . . . . . . . . . . . . . . 7 3 Theoretical Framework

Cronin, Alex D.

187

ROTATIONAL SPECTRA OF SMALL PAHs: ACENAPHTHENE, ACENAPHTHYLENE, AZULENE, AND FLUORENE  

E-Print Network [OSTI]

ROTATIONAL SPECTRA OF SMALL PAHs: ACENAPHTHENE, ACENAPHTHYLENE, AZULENE, AND FLUORENE S. Thorwirth in the frequency range from 7 to 37 GHz. Initial searches for acenaphthene (C12H10), acenaphthylene (C12H8 and experimentally derived ground-state rotational constants is achieved. Selected transitions of acenaphthene

Thorwirth, Sven

188

Optimizing rotational acceleration curves for minimum energy use in electric  

E-Print Network [OSTI]

Optimizing rotational acceleration curves for minimum energy use in electric motors. 12/15/06 Fall the optimal efficiency of a motor for any input values of motor constants, distance, or time. In every of the inspiration to find which rotational acceleration curve for the used motors would be most efficient. We really

Ruina, Andy L.

189

Veteran's Administration Medical Center General Plastic Surgery Rotation  

E-Print Network [OSTI]

Veteran's Administration Medical Center General Plastic Surgery Rotation 2nd year Resident By the end of the Plastic Surgery Rotation at the VAMC, the 2nd year residents are expected to expand with the following conditions that require plastic surgery, including but not limited to: · Upper extremity

Cui, Yan

190

Modeling and Control of Surge and Rotating Stall in Compressors  

E-Print Network [OSTI]

in connection with acceleration of the compressor. Finally, a model for a centrifugal compression systemModeling and Control of Surge and Rotating Stall in Compressors Dr.ing. thesis Jan Tommy Gravdahl of rotating stall and surge in compressors. A close coupled valve is included in the Moore

Gravdahl, Jan Tommy

191

Waveparticle interactions in rotating mirrorsa) Abraham J. Fettermanb)  

E-Print Network [OSTI]

rotating plasmas feature an unusual effect: particles are diffused by waves in both potential energy and kinetic energy. This wave­particle interaction generalizes the alpha channeling effect, in which radio frequency waves are used to remove alpha particles collisionlessly at low energy. In rotating plasmas

192

Magnetic and antimagnetic rotation in covariant density functional theory  

SciTech Connect (OSTI)

Progress on microscopic and self-consistent description of the magnetic rotation and antimagnetic rotation phenomena in tilted axis cranking relativistic mean-field theory based on a point-coupling interaction are briefly reviewed. In particular, the microscopic pictures of the shears mechanism in {sup 60}Ni and the two shears-like mechanism in {sup 105}Cd are discussed.

Zhao, P. W.; Liang, H. Z.; Peng, J.; Ring, P.; Zhang, S. Q.; Meng, J. [State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China); Department of Physics, Beijing Normal University, Beijing 100875 (China); State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China) and Physik Department, Technische Universitat Muenchen, D-85747 Garching (Germany); State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China); State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China) and Department of Physics, University of Stellenbosch, Stellenbosch (South Africa)

2012-10-20T23:59:59.000Z

193

Differential rotation of the unstable nonlinear r-modes  

E-Print Network [OSTI]

At second order in perturbation theory, the $r$-modes of uniformly rotating stars include an axisymmetric part that can be identified with differential rotation of the background star. If one does not include radiation-reaction, the differential rotation is constant in time and has been computed by S\\'a. It has a gauge dependence associated with the family of time-independent perturbations that add differential rotation to the unperturbed equilibrium star: For stars with a barotropic equation of state, one can add to the time-independent second-order solution arbitrary differential rotation that is stratified on cylinders (that is a function of distance $\\varpi$ to the axis of rotation). We show here that the gravitational radiation-reaction force that drives the $r$-mode instability removes this gauge freedom: The expontially growing differential rotation of the unstable second-order $r$-mode is unique. We derive a general expression for this rotation law for Newtonian models and evaluate it explicitly for s...

Friedman, John L; Lockitch, Keith H

2015-01-01T23:59:59.000Z

194

Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates  

E-Print Network [OSTI]

be homogeneous within the condensate we prove by means of an asymptotic analysis in the strongly interactingInhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates M. Correggia , N. Rougerieb, France. May 10, 2012 Abstract We consider a 2D rotating Bose gas described by the Gross-Pitaevskii (GP

Paris-Sud XI, Université de

195

Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates  

E-Print Network [OSTI]

should be homogeneous within the condensate we prove by means of an asymptotic analysis in the stronglyInhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates M. Correggia , N. Rougerieb, France. September 19, 2012 Abstract We consider a 2D rotating Bose gas described by the Gross

Paris-Sud XI, Université de

196

Applications of Artificial Neural Networks (ANNs) to Rotating Equipment  

E-Print Network [OSTI]

including (but not limited to) oil and gas industries, petrochemical plants, power plants, transmission.asgari@pg.canterbury.ac.nz Abstract Rotating equipment is the beating heart of nearly all industrial plants and specifically plays) [1]. Today, a variety of rotating equipment is being used widely in different industrial plants

Sainudiin, Raazesh

197

AIAA 20023642 Effect of Rotation on Flow in a  

E-Print Network [OSTI]

AIAA 2002­3642 Effect of Rotation on Flow in a Ribbed Rotating Turbine Blade Cooling Duct Model of aircraft gas turbine engines, thereby in- creasing the resulting thrust. These improvements are extremely to these advancements is the structural integrity of the gas turbine engines themselves. Cur- rently available materials

Jacob, Jamey

198

Omni-directional and holonomic rolling platform with decoupled rotational and translational degrees of freedom  

DOE Patents [OSTI]

A wheel assembly includes a support, a cage rotatably mounted on the support and having a longitudinal rotation axis, a first ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis of the cage, and a second ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis or the cage and to the rotation axis of the first ball wheel. A control circuit includes a photodetector signal which indicates ground contact for each ball wheel, and a tachometer which indicates actual drive shaft velocity. 6 figures.

Pin, F.G.; Killough, S.M.

1994-12-20T23:59:59.000Z

199

Omni-directional and holonomic rolling platform with decoupled rotational and translational degrees of freedom  

SciTech Connect (OSTI)

A wheel assembly includes a support, a cage rotatably mounted on the support and having a longitudinal rotation axis, a first ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis of the cage, and a second ball wheel rotatably mounted in the cage and having a rotation axis orthogonal to the rotation axis or the cage and to the rotation axis of the first ball wheel. A control circuit includes a photodetector signal which indicates ground contact for each ball wheel, and a tachometer which indicates actual drive shaft velocity.

Pin, Francois G. (Knoxville, TN); Killough, Stephen M. (Knoxville, TN)

1994-01-01T23:59:59.000Z

200

Semiclassical pair production rate for rotating electric fields  

E-Print Network [OSTI]

We semiclassically investigate Schwinger pair production for pulsed rotating electric fields depending on time. To do so we solve the Dirac equation for two-component fields in a WKB-like approximation. The result shows that for two-component fields the spin distribution of produced pairs is generally not $1:1$. As a result the pair creation rates of spinor and scalar quantum electro dynamics (QED) are different even for one pair of turning points. For rotating electric fields the pair creation rate is dominated by particles with a specific spin depending on the sense of rotation for a certain range of pulse lengths and frequencies. We present an analytical solution for the momentum spectrum of the constant rotating field. We find interference effects not only in the momentum spectrum but also in the total particle number of rotating electric fields.

Eckhard Strobel; She-Sheng Xue

2015-02-09T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Selective Rotational Excitation of Molecular Isotopes and Nuclear Spin Isomers  

E-Print Network [OSTI]

Following excitation by a strong ultra-short laser pulse, molecules develop coordinated rotational motion, exhibiting transient alignment along the direction of the laser electric field, followed by periodic full and fractional revivals that depend on the molecular rotational constants. In mixtures, the different species undergo similar rotational dynamics, all starting together but evolving differently with each demonstrating its own periodic revival cycles. For a bimolecular mixture of linear molecules, at predetermined times, one species may attain a maximally aligned state while the other is anti-aligned (i.e. molecular axes are confined in a plane perpendicular to the laser electric field direction). By a properly timed second laser pulse, the rotational excitation of the undesired species may be almost completely removed leaving only the desired species to rotate and periodically realign, thus facilitating further selective manipulations by polarized light. In this paper, such double excitation schemes are demonstrated for mixtures of molecular isotopes (isotopologues) and for nuclear spin isomers.

Sharly Fleischer; Ilya. Sh. Averbukh; Yehiam Prior

2007-02-15T23:59:59.000Z

202

ZAKKAROFF et al.: RECOVERY OF SLICE ROTATIONS IN CARDIAC MR SERIES 1 Recovery of Slice Rotations with the Stack  

E-Print Network [OSTI]

ZAKKAROFF et al.: RECOVERY OF SLICE ROTATIONS IN CARDIAC MR SERIES 1 Recovery of Slice Rotations with the Stack Alignment Transform in Cardiac MR Series Constantine Zakkaroff1 mnkz@leeds.ac.uk Aleksandra Radjenovic2 a.radjenovic@leeds.ac.uk John Greenwood3 j.greenwood@leeds.ac.uk Derek Magee1 d

Magee, Derek

203

Molecular heat pump for rotational states  

E-Print Network [OSTI]

In this work we investigate the theory for three different uni-directional population transfer schemes in trapped multilevel systems which can be utilized to cool molecular ions. The approach we use exploits the laser-induced coupling between the internal and motional degrees of freedom so that the internal state of a molecule can be mapped onto the motion of that molecule in an external trapping potential. By sympathetically cooling the translational motion back into its ground state the mapping process can be employed as part of a cooling scheme for molecular rotational levels. This step is achieved through a common mode involving a laser-cooled atom trapped alongside the molecule. For the coherent mapping we will focus on adiabatic passage techniques which may be expected to provide robust and efficient population transfers. By applying far-detuned chirped adiabatic rapid passage pulses we are able to achieve an efficiency of better than 98% for realistic parameters and including spontaneous emission. Even...

Lazarou, C; Garraway, B M

2010-01-01T23:59:59.000Z

204

Molecular heat pump for rotational states  

E-Print Network [OSTI]

In this work we investigate the theory for three different uni-directional population transfer schemes in trapped multilevel systems which can be utilized to cool molecular ions. The approach we use exploits the laser-induced coupling between the internal and motional degrees of freedom so that the internal state of a molecule can be mapped onto the motion of that molecule in an external trapping potential. By sympathetically cooling the translational motion back into its ground state the mapping process can be employed as part of a cooling scheme for molecular rotational levels. This step is achieved through a common mode involving a laser-cooled atom trapped alongside the molecule. For the coherent mapping we will focus on adiabatic passage techniques which may be expected to provide robust and efficient population transfers. By applying far-detuned chirped adiabatic rapid passage pulses we are able to achieve an efficiency of better than 98% for realistic parameters and including spontaneous emission. Even though our main focus is on cooling molecular states, the analysis of the different adiabatic methods has general features which can be applied to atomic systems.

C. Lazarou; M. Keller; B. M. Garraway

2010-01-25T23:59:59.000Z

205

Solid State Replacement of Rotating Mirror Cameras  

SciTech Connect (OSTI)

Rotating mirror cameras have been the mainstay of mega-frame per second imaging for decades. There is still no electronic camera that can match a film based rotary mirror camera for the combination of frame count, speed, resolution and dynamic range. The rotary mirror cameras are predominantly used in the range of 0.1 to 100 micro-seconds per frame, for 25 to more than a hundred frames. Electron tube gated cameras dominate the sub microsecond regime but are frame count limited. Video cameras are pushing into the microsecond regime but are resolution limited by the high data rates. An all solid state architecture, dubbed ''In-situ Storage Image Sensor'' or ''ISIS'', by Prof. Goji Etoh, has made its first appearance into the market and its evaluation is discussed. Recent work at Lawrence Livermore National Laboratory has concentrated both on evaluation of the presently available technologies and exploring the capabilities of the ISIS architecture. It is clear though there is presently no single chip camera that can simultaneously match the rotary mirror cameras, the ISIS architecture has the potential to approach their performance.

Frank, A M; Bartolick, J M

2006-08-25T23:59:59.000Z

206

Gravitational waves from rapidly rotating neutron stars  

E-Print Network [OSTI]

Rapidly rotating neutron stars in Low Mass X-ray Binaries have been proposed as an interesting source of gravitational waves. In this chapter we present estimates of the gravitational wave emission for various scenarios, given the (electromagnetically) observed characteristics of these systems. First of all we focus on the r-mode instability and show that a 'minimal' neutron star model (which does not incorporate exotica in the core, dynamically important magnetic fields or superfluid degrees of freedom), is not consistent with observations. We then present estimates of both thermally induced and magnetically sustained mountains in the crust. In general magnetic mountains are likely to be detectable only if the buried magnetic field of the star is of the order of $B\\approx 10^{12}$ G. In the thermal mountain case we find that gravitational wave emission from persistent systems may be detected by ground based interferometers. Finally we re-asses the idea that gravitational wave emission may be balancing the accretion torque in these systems, and show that in most cases the disc/magnetosphere interaction can account for the observed spin periods.

Brynmor Haskell; Nils Andersson; Caroline D`Angelo; Nathalie Degenaar; Kostas Glampedakis; Wynn C. G. Ho; Paul D. Lasky; Andrew Melatos; Manuel Oppenoorth; Alessandro Patruno; Maxim Priymak

2014-07-31T23:59:59.000Z

207

Galaxy rotation curves in de Sitter space  

E-Print Network [OSTI]

The observed positive cosmological constant $\\Lambda$ and Hubble constant $H_0$ introduce a background of de Sitter gravitons of mass $m_0=\\sqrt{\\Lambda}\\hbar/c$ at a non-relativistic temperature $k_BT_{dS}=a_{H}\\hbar/\\pi c$, $a_H=H_0c$, where $\\hbar$ denotes the Planck constant and $c$ the velocity of light. In this cosmology, gravitational interactions are parameterized by the inverse temperature $\\beta=T_{dS}/T$ of the vacuum. The high and low $\\beta$ limits produce an acceleration $a\\simeq\\sqrt{a_Na_0}$, $a_0=2a_{H}/(1+\\beta_{dS})\\simeq 1.37\\times 10^{-8}$ cm s$^{-2}$, observed in observed galaxy rotation curves and, respectively, Newton's law. Gravitation may be anomalously weak in a transition about $2.17\\, {M_{11}^{1/2}} \\, \\mbox{kpc}$ around a galaxy of $M=M_{11}10^{11}M_\\odot$.

Maurice H. P. M. van Putten

2014-11-10T23:59:59.000Z

208

Solar rotation rate and its gradients during cycle 23  

E-Print Network [OSTI]

Available helioseismic data now span almost the entire solar activity cycle 23 making it possible to study solar-cycle related changes of the solar rotation rate in detail. In this paper we study how the solar rotation rate, in particular, the zonal flows change with time. In addition to the zonal flows that show a well known pattern in the solar convection zone, we also study changes in the radial and latitudinal gradients of the rotation rate, particularly in the shear layer that is present in the immediate sub-surface layers of the Sun. In the case of the zonal-flow pattern, we find that the band indicating fast rotating region close to the equator seems to have bifurcated around 2005. Our investigation of the rotation-rate gradients show that the relative variation in the rotation-rate gradients is about 20% or more of their average values, which is much larger than the relative variation in the rotation rate itself. These results can be used to test predictions of various solar dynamo models.

H. M. Antia; Sarbani Basu; S. M. Chitre

2008-05-22T23:59:59.000Z

209

ROTATION OF MERCURY: THEORETICAL ANALYSIS OF THE DYNAMICS OF A RIGID ELLIPSOIDAL PLANET  

E-Print Network [OSTI]

Laboratory ROTATION OF MERCURY: THEDRETICAL ANALYSIS OF THEW -7405-eng-48 ROTATION OF MERCURY: THEORETICAL ANALYSIS OFfor the rotation of Mercury is sho'ln to imply locked-in

Laslett, L. Jackson

2008-01-01T23:59:59.000Z

210

Optical depth measurements by shadow-band radiometers and their uncertainties  

E-Print Network [OSTI]

and Atmospheric Administration Surface Radiation (SURFRAD) Network, and NASA Solar Irradiance Research Network important product of Sun-photometric measurements. [According to the American Meteoro- logical Society (AMS Measurement (ARM) Program [7]. This network con- sists of 21 instruments located at the SGP Central (CF

211

Landau Damping of Geodesic Acoustic Mode in Toroidally Rotating Tokamaks  

E-Print Network [OSTI]

Geodesic acoustic mode (GAM) is analyzed by using gyro-kinetic equations applicable to low-frequency microinstabilities in a rotating axisymmetric plasma. Dispersion relation of GAM in the presence of arbitrary Mach number is analytically dervied. Toroidal rotation plays the same effects on the GAM regardless of the orientation of equilibrium flow. It is shown that the toroidal Mach number increases the GAM frequency and dramatically decreases the Landau damping rate. Classical gyro-kinetic equation is examined to be not suitable for describing the GAM in a torodially rotating tokamak plasma even for very small Mach number.

Ren, Haijun

2015-01-01T23:59:59.000Z

212

3D rotational diffusion microrheology using 2D video microscopy  

E-Print Network [OSTI]

We propose a simple way to perform three-dimensional (3D) rotational microrheology using two-dimensional (2D) video microscopy. The 3D rotational brownian motion of micrometric wires in a viscous fluid is deduced from their projection on the focal plane of an optical microscope objective. The rotational diffusion coefficient of the wires of length between 1-100 \\mu m is extracted, as well as their diameter distribution in good agreement with electron microscopy measurements. This is a promising way to characterize soft visco-elastic materials, and probe the dimensions of anisotropic objects.

Rémy Colin; Minhao Yan; Loudjy Chevry; Jean-François Berret; Bérengère Abou

2012-01-05T23:59:59.000Z

213

Temporal variations of the rotation rate in the solar interior  

E-Print Network [OSTI]

The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995-99. We find alternating latitudinal bands of faster and slower rotation which appear to move towards the equator with time - similar to the torsional oscillations seen at the solar surface. This flow pattern appears to persist to a depth of about 0.1R_sun and in this region its magnitude is well correlated with solar activity indices. We do not find any periodic or systematic changes in the rotation rate near the base of the convection zone.

H. M. Antia; Sarbani Basu

2000-04-25T23:59:59.000Z

214

Linear Stability and Subcritical Turbulence in Rotating Shear Flows  

E-Print Network [OSTI]

The relation between rotating plane Couette and Taylor-Couette flows is clarified. The identity of their linear stability limits is explained by considering the effect of the Coriolis force in the rotating frame. Experimental data are used to quantify the behavior of the minimum Reynolds number for subcritical turbulence as a function of rotation and curvature. This last dependence is understood through a phenomenological analysis, which also implies that the Coriolis force reduces the efficiency of subcritical turbulent transport with respect to nonrotating flows, as observed numerically.

P. -Y. Longaretti

2003-05-28T23:59:59.000Z

215

Quasi-toroidal oscillations in rotating relativistic stars  

E-Print Network [OSTI]

Quasi-toroidal oscillations in slowly rotating stars are examined in the framework of general relativity. The oscillation frequency to first order of the rotation rate is not a single value even for uniform rotation unlike the Newtonian case. All the oscillation frequencies of the r-modes are purely neutral and form a continuous spectrum limited to a certain range. The allowed frequencies are determined by the resonance condition between the perturbation and background mean flow. The resonant frequency varies with the radius according to general relativistic dragging effect.

Yasufumi Kojima

1997-09-02T23:59:59.000Z

216

Faraday rotation spectroscopy of nitrogen dioxide based on a widely tunable external cavity quantum cascade laser  

E-Print Network [OSTI]

Faraday rotation spectroscopy of nitrogen dioxide based on a widely tunable external cavity quantum: Faraday Rotation Spectroscopy, external-cavity quantum cascade laser, nitrogen dioxide, trace

217

E-Print Network 3.0 - anterior rotational osteotomy Sample Search...  

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

J... prosthetic control systems. The Osseo-Magnetic Link (OML) is a novel humeral or wrist rotation control system... . This allows the use of volitional bone rotation to...

218

Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics...  

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

Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics in orthorhombic ammonia borane. Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics in...

219

axis rotating states: Topics by E-print Network  

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

20 21 22 23 24 25 Next Page Last Page Topic Index 21 Rotation speed and stellar axis inclination from p modes: How CoRoT would see other suns Astrophysics (arXiv) Summary: In the...

220

Aerodynamic performance measurements in a counter-rotating aspirated compressor  

E-Print Network [OSTI]

This thesis is an experimental investigation of the aerodynamic performances of a counter-rotating aspirated compressor. This compressor is implemented in a blow-down facility, which gives rigorous simulation of the ...

Onnée, Jean-François

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Ferrofluid surface and volume flows in uniform rotating magnetic fields  

E-Print Network [OSTI]

Ferrofluid surface and volume effects in uniform dc and rotating magnetic fields are studied. Theory and corroborating measurements are presented for meniscus shapes and resulting surface driven flows, spin-up flows, and ...

Elborai, Shihab M. (Shihab Mahmoud), 1977-

2006-01-01T23:59:59.000Z

222

ROTATING LINE CAMERAS: EPIPOLAR GEOMETRY AND SPATIAL SAMPLING  

E-Print Network [OSTI]

project 3D scenes on a cylindric sur- face, where one or multiple rotating sensor lines allow to compose for controlling this error, allowing to adjust the camera position- ing at the time of photo shooting. The report

223

Dynamo Saturation in Rapidly Rotating Solar-Type Stars  

E-Print Network [OSTI]

The magnetic activity of solar-type stars generally increases with stellar rotation rate. The increase, however, saturates for fast rotation. The Babcock-Leighton mechanism of stellar dynamos saturates as well when the mean tilt-angle of active regions approaches ninety degrees. Saturation of magnetic activity may be a consequence of this property of the Babcock-Leighton mechanism. Stellar dynamo models with a tilt-angle proportional to the rotation rate are constructed to probe this idea. Two versions of the model - treating the tilt-angles globally and using Joy's law for its latitude dependence - are considered. Both models show a saturation of dynamo-generated magnetic flux at high rotation rates. The model with latitude-dependent tilt-angles shows also a change in dynamo regime in the saturation region. The new regime combines a cyclic dynamo at low latitudes with an (almost) steady polar dynamo.

Kitchatinov, L L

2015-01-01T23:59:59.000Z

224

Time-dependent resonant magneto-optical rotation  

E-Print Network [OSTI]

Results of a fairly straightforward experiment on resonant magneto-optical rotation by rubidium-87 atoms revealed strong time-dependence of the polarization plane of light emerging from atomic vapors following a sudden irradiation with a laser beam. The rotation of the plane appears as a not direct consequence of the influence of the magnetic field on atoms. Reported measurements conducted using a vapor cell without any buffer gas or an anti-relaxation wall coating show that transmitted light has initially the same (linear) polarization as the incident one. Rotation of the polarization plane caused by an axial magnetic field develops in time scales similar to the pace of establishing the optical pumping/relaxation equilibrium in the atomic ensemble. The traditional passive Faraday rotation picture providing working description for the resonant magneto-optical effects in steady-state conditions does not explain the observed sequence of evolution of the polarization. The picture has to be augmented with analysi...

Dziczek, Dariusz

2015-01-01T23:59:59.000Z

225

Measurement of the Integrated Faraday Rotations of BL Lac Objects  

E-Print Network [OSTI]

We present the results of multi-frequency polarization VLA observations of radio sources from the complete sample of northern, radio-bright BL Lac objects compiled by H. Kuhr and G. Schmidt. These were used to determine the integrated rotation measures of 18 objects, 15 of which had never been measured previously, which hindered analysis of the intrinsic polarization properties of objects in the complete sample. These measurements make it possible to correct the observed orientations of the linear polarizations of these sources for the effect of Faraday rotation. The most probable origin for Faraday rotation in these objects is the Galactic interstellar medium. The results presented complete measurements of the integrated rotation measures for all 34 sources in the complete sample of BL Lac objects.

A. B. Pushkarev

2003-07-09T23:59:59.000Z

226

Design and cavitation performance of contra-rotating propellers  

E-Print Network [OSTI]

Improvement of the propulsive efficiency of ships has always been one of the main objectives for naval architects and marine engineers. Contra-Rotating propellers (CRP) are propulsor configurations offering higher efficiency ...

Laskos, Dimitrios

2010-01-01T23:59:59.000Z

227

Subcritical turbulent transition in rotating and curved shear flows  

E-Print Network [OSTI]

The effects of global flow rotation and curvature on the subcritical transition to turbulence in shear flows are examined. The relevant time-scales of the problem are identified by a decomposition of the flow into a laminar and a deviation from laminar parts, which is performed for rotating plane Couette and Taylor-Couette flows. The usefulness and relevance of this procedure are discussed at the same time. By comparing the self-sustaining process time-scale to the time-scales previously identified, an interpretation is brought to light for the behavior of the transition Reynolds number with the rotation number and relative gap width in the whole neighborhood (in parameter space) of the non-rotating plane Couette flow covered by the available data.

P-Y. Longaretti; O. Dauchot

2005-09-19T23:59:59.000Z

228

Short-period seismic rotations and translations recorded by Rotaphone  

E-Print Network [OSTI]

-period Rotaphone records of events induced by natural and/or anthropogenic sources 31 5.1 Records of quarry blasts Rotation to translation relations 39 7 The problem of seismic translational components being contaminated

Cerveny, Vlastislav

229

Contrast from rotating frame relaxation by adiabatic pulses  

DOE Patents [OSTI]

This document discusses, among other things, a system and method for modulating transverse and longitudinal relaxation time contrast in a rotating frame based on a train of radio frequency pulses.

Michaeli, Shalom (St. Paul, MN); Garwood, Michael G. (Medina, MN); Ugurbil, Kamil (Minneapolis, MN); Sorce, Dennis J. (Cockeysville, MD)

2007-10-09T23:59:59.000Z

230

EFFECT OF DARK MATTER HALO SUBSTRUCTURES ON GALAXY ROTATION CURVES  

SciTech Connect (OSTI)

In this paper, the effect of halo substructures on galaxy rotation curves is investigated using a simple model of dark matter clustering. A dark matter halo density profile is developed based only on the scale-free nature of clustering that leads to a statistically self-similar distribution of the substructures at the galactic scale. A semi-analytical method is used to derive rotation curves for such a clumpy dark matter density profile. It is found that the halo substructures significantly affect the galaxy velocity field. Based on the fractal geometry of the halo, this self-consistent model predicts a Navarro-Frenk-White-like rotation curve and a scale-free power spectrum of the rotation velocity fluctuations.

Roy, Nirupam, E-mail: nroy@aoc.nrao.ed [NRAO, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801 (United States)

2010-11-01T23:59:59.000Z

231

On the Planetary acceleration and the Rotation of the Earth  

E-Print Network [OSTI]

We have developed a model for the Earth rotation that gives a good account (data) of the Earth astronomical parameters. These data can be compared with the ones obtained using space-base telescopes. The expansion of the universe has an impact on the rotation of planets, and in particular, the Earth. The expansion of the universe causes an acceleration that is exhibited by all planets.

Arbab I. Arbab

2007-08-06T23:59:59.000Z

232

Manipulator for rotating and translating a sample holder  

DOE Patents [OSTI]

A manipulator for use in e.g. a Transmission Electron Microscope (TEM) is described, said manipulator capable of rotating and translating a sample holder (4). The manipulator clasps the round sample holder between two members (3A, 3B), said members mounted on actuators (2A, 2B). Moving the actuators in the same direction results in a translation of the sample holder, while moving the actuators in opposite directions results in a rotation of the sample holder.

van de Water, Jeroen (Breugel, NL); van den Oetelaar, Johannes (Eindhoven, NL); Wagner, Raymond (Gorinchem, NL); Slingerland, Hendrik Nicolaas (Venlo, NL); Bruggers, Jan Willem (Eindhoven, NL); Ottevanger, Adriaan Huibert Dirk (Malden, NL); Schmid, Andreas (Berkeley, CA); Olson, Eric A. (Champaign, IL); Petrov, Ivan G. (Champaign, IL); Donchev, Todor I. (Urbana, IL); Duden, Thomas (Kensington, CA)

2011-02-08T23:59:59.000Z

233

Rotation-induced nonlinear wavepackets in internal waves  

SciTech Connect (OSTI)

The long time effect of weak rotation on an internal solitary wave is the decay into inertia-gravity waves and the eventual formation of a localised wavepacket. Here this initial value problem is considered within the context of the Ostrovsky, or the rotation-modified Korteweg-de Vries (KdV), equation and a numerical method for obtaining accurate wavepacket solutions is presented. The flow evolutions are described in the regimes of relatively-strong and relatively-weak rotational effects. When rotational effects are relatively strong a second-order soliton solution of the nonlinear Schrödinger equation accurately predicts the shape, and phase and group velocities of the numerically determined wavepackets. It is suggested that these solitons may form from a local Benjamin-Feir instability in the inertia-gravity wave-train radiated when a KdV solitary wave rapidly adjusts to the presence of strong rotation. When rotational effects are relatively weak the initial KdV solitary wave remains coherent longer, decaying only slowly due to weak radiation and modulational instability is no longer relevant. Wavepacket solutions in this regime appear to consist of a modulated KdV soliton wavetrain propagating on a slowly varying background of finite extent.

Whitfield, A. J., E-mail: ashley.whitfield.12@ucl.ac.uk; Johnson, E. R., E-mail: e.johnson@ucl.ac.uk [Department of Mathematics, University College London, London WC1E 6BT (United Kingdom)

2014-05-15T23:59:59.000Z

234

Influence of Rotations on the Critical State of Soil Mechanics  

E-Print Network [OSTI]

The ability of grains to rotate can play a crucial role on the collective behavior of granular media. It has been observed in computer simulations that imposing a torque at the contacts modifies the force chains, making support chains less important. In this work we investigate the effect of a gradual hindering of the grains rotations on the so-called critical state of soil mechanics. The critical state is an asymptotic state independent of the initial solid fraction where deformations occur at a constant shear strength and compactness. We quantify the difficulty to rotate by a friction coefficient at the level of particles, acting like a threshold. We explore the effect of this particle-level friction coefficient on the critical state by means of molecular dynamics simulations of a simple shear test on a poly-disperse sphere packing. We found that the larger the difficulty to rotate, the larger the final shear strength of the sample. Other micro-mechanical variables, like the structural anisotropy and the distribution of forces, are also influenced by the threshold. These results reveal the key role of rotations on the critical behavior of soils and suggest the inclusion of rotational variables into their constitutive equations.

W. F. Oquendo; J. D. Muñoz; A. Lizcano

2010-11-23T23:59:59.000Z

235

Magneto-Rotational Transport in the Early Sun  

E-Print Network [OSTI]

Angular momentum transport must have occurred in the Sun's radiative zone to explain its current solid body rotation. We survey the stability of the early Sun's radiative zone with respect to diffusive rotational instabilities, for a variety of plausible past configurations. We find that the (faster rotating) early Sun was prone to rotational instabilities even if only weak levels of radial differential rotation were present, while the current Sun is not. Stability domains are determined by approximate balance between dynamical and diffusive timescales, allowing generalizations to other stellar contexts. Depending on the strength and geometry of the weak magnetic field present, the fastest growing unstable mode can be hydrodynamic or magneto-hydrodynamic (MHD) in nature. Our results suggest that diffusive MHD modes may be more efficient at transporting angular momentum than their hydrodynamic (``Goldreich-Schubert-Fricke'') counterparts because the minimum spatial scale required for magnetic tension to be destabilizing limits the otherwise very small scales favored by double-diffusive instabilities. Diffusive magneto-rotational instabilities are thus attractive candidates for angular momentum transport in the early Sun's radiative zone.

Kristen Menou; Joel LeMer

2006-06-14T23:59:59.000Z

236

From static to rotating to conformal static solutions: Rotating imperfect fluid wormholes with(out) electric or magnetic field  

E-Print Network [OSTI]

We derive a shortcut stationary metric formula for generating imperfect fluid rotating solutions, in Boyer-Lindquist coordinates, from spherically symmetric static ones. We explore the properties of the curvature scalar and stress-energy tensor for all types of rotating regular solutions we can generate without restricting ourselves to specific examples of regular solutions (regular black holes or wormholes). We show through examples how it is generally possible to generate an imperfect fluid regular rotating solution via radial coordinate transformations. We derive rotating wormholes that are modeled as imperfect fluids and discuss their physical properties that are independent on the way the stress-energy tensor is interpreted. A solution modeling an imperfect fluid rotating loop black hole is briefly discussed. We then specialize to the recently discussed stable exotic dust Ellis wormhole emerged in a source-free radial electric or magnetic field, generate its, conjecturally stable, rotating counterpart which turns out to be an exotic imperfect fluid wormhole and determine the stress-energy tensor of both the imperfect fluid and the electric or magnetic field.

Mustapha Azreg-Aïnou

2014-04-16T23:59:59.000Z

237

Equatorial symmetry of Boussinesq convective solutions in a rotating spherical shell allowing rotation of the inner and outer spheres  

SciTech Connect (OSTI)

We investigate properties of convective solutions of the Boussinesq thermal convection in a moderately rotating spherical shell allowing the respective rotation of the inner and outer spheres due to the viscous torque of the fluid. The ratio of the inner and outer radii of the spheres, the Prandtl number, and the Taylor number are fixed to 0.4, 1, and 500{sup 2}, respectively. The Rayleigh number is varied from 2.6 × 10{sup 4} to 3.4 × 10{sup 4}. In this parameter range, the behaviours of obtained asymptotic convective solutions are almost similar to those in the system whose inner and outer spheres are restricted to rotate with the same constant angular velocity, although the difference is found in the transition process to chaotic solutions. The convective solution changes from an equatorially symmetric quasi-periodic one to an equatorially symmetric chaotic one, and further to an equatorially asymmetric chaotic one, as the Rayleigh number is increased. This is in contrast to the transition in the system whose inner and outer spheres are assumed to rotate with the same constant angular velocity, where the convective solution changes from an equatorially symmetric quasi-periodic one, to an equatorially asymmetric quasi-periodic one, and to equatorially asymmetric chaotic one. The inner sphere rotates in the retrograde direction on average in the parameter range; however, it sometimes undergoes the prograde rotation when the convective solution becomes chaotic.

Kimura, Keiji; Takehiro, Shin-ichi; Yamada, Michio [Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502 (Japan)

2014-08-15T23:59:59.000Z

238

Rotational stability of a long field-reversed configuration  

SciTech Connect (OSTI)

Rotationally driven modes of long systems with dominantly axial magnetic field are considered. We apply the incompressible model and order axial wavenumber small. A recently developed gyro-viscous model is incorporated. A one-dimensional equilibrium is assumed, but radial profiles are arbitrary. The dominant toroidal (azimuthal) mode numbers ?=1 and ?=2 modes are examined for a variety of non-reversed (B) and reversed profiles. Previous results for both systems with rigid rotor equilibria are reproduced. New results are obtained by incorporation of finite axial wavenumber and by relaxing the assumption of rigid electron and ion rotation. It is shown that the frequently troublesome ?=2 field reversed configuration (FRC) mode is not strongly affected by ion kinetic effects (in contrast to non-reversed cases) and is likely stabilized experimentally only by finite length effects. It is also shown that the ?=1 wobble mode has a complicated behavior and is affected by a variety of configuration and profile effects. The rotationally driven ?=1 wobble is completely stabilized by strong rotational shear, which is anticipated to be active in high performance FRC experiments. Thus, observed wobble modes in these systems are likely not driven by rotation alone.

Barnes, D. C., E-mail: coronadocon@msn.com; Steinhauer, L. C. [Tri Alpha Energy, Rancho Santa Margarita, California 92688 (United States)] [Tri Alpha Energy, Rancho Santa Margarita, California 92688 (United States)

2014-02-15T23:59:59.000Z

239

Light defection due to a charged, rotating body  

E-Print Network [OSTI]

According to GTR and subsequent developments in the field, it is known that there are three factors namely mass, rotation and charge that can influence the space-time geometry. Accordingly, we discuss the effect of space-time geometry of a charged, rotating body on the motion of the light ray. We obtained the expression for equatorial defection of light due to such a body up to fourth order term. In our expression for defection angle it is clear that charge can influence the path of light ray. We used the null geodesic approach of light ray for our calculation. If we set the charge to zero our expression of bending angle gets reduced to the Kerr equatorial bending angle.If we set rotation to zero our expression reduces to Resinner-Nordstr$\\ddot{o}$m defection angle and if we set both charge and rotation to zero our expression reduces to Schwarzschild bending angle. However, we get non-zero bending angle for a hypothetical massless, rotating, charged body.

Sarani Chakraborty; A. K. Sen

2014-06-05T23:59:59.000Z

240

The rotational behavior of Kepler Stars with Planets  

E-Print Network [OSTI]

We analyzed the host stars of the present sample of confirmed planets detected by Kepler and Kepler Objects of Interest (KOI) to compute new photometric rotation periods and to study the behavior of their angular momentum. Lomb-Scargle periodograms and wavelet maps were computed for 3,807 stars. For 540 of these stars, we were able to detect rotational modulation of the light curves at a significance level of greater than 99%. For 63 of these 540 stars, no rotation measurements were previously available in the literature. According to the published masses and evolutionary tracks of the stars in this sample, the sample is composed of M- to F-type stars (with masses of 0.48-1.53 M$_{\\odot}$) with rotation periods that span a range of 2 to 89 days. These periods exhibit an excellent agreement with previously reported (for the stars for which such values are available), and the observed rotational period distribution strongly agrees with theoretical predictions. Furthermore, for the 540 sources considered here, t...

Paz-Chinchón, F; Bravo, J P; de Freitas, D B; Lopes, C E Ferreira; Alves, S; Catelan, M; Martins, B L Canto; De Medeiros, J R

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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.


241

Steady states of the parametric rotator and pendulum  

E-Print Network [OSTI]

We discuss several steady-state rotation and oscillation modes of the planar parametric rotator and pendulum with damping. We consider a general elliptic trajectory of the suspension point for both rotator and pendulum, for the latter at an arbitrary angle with gravity, with linear and circular trajectories as particular cases. We treat the damped, non-linear equation of motion of the parametric rotator and pendulum perturbatively for small parametric excitation and damping, although our perturbative approach can be extended to other regimes as well. Our treatment involves only ordinary second-order differential equations with constant coefficients, and provides numerically accurate perturbative solutions in terms of elementary functions. Some of the steady-state rotation and oscillation modes studied here have not been discussed in the previous literature. Other well-known ones, such as parametric resonance and the inverted pendulum, are extended to elliptic parametric excitation tilted with respect to gravity. The results presented here should be accessible to advanced undergraduates, and of interest to graduate students and specialists in the field of non-linear mechanics.

Antonio O. Bouzas

2011-03-08T23:59:59.000Z

242

Magnetic Rotator Winds and Keplerian Disks of Hot Stars  

E-Print Network [OSTI]

We consider rotating magnetic stars with winds and disks. We establish a theorem that relates the angular velocity of a disk region with no meridional motion to the angular velocity of the star. Also, we show that for a given value of the magnetic field strength, if the rotation rate is too high or the flow velocity into the shock boundary is too low, a Keplerian disk region will not be formed. We develop a model for the formation of disks in magnetic rotators through the processes of fill-up and diffusion into Keplerian orbits. At the end of the fill-up stage the density of the disk increases significantly and the magnetic force in the disk becomes negligible. We derive analytical expressions for the inner and outer radii of Keplerian disks in terms of the stellar rotation rate. A disk can form if the meridional component Bm of the field at the stellar surface is larger than a minimum value. The radial extent of the Keplerian region becomes larger for larger values of Bm and is largest when Bm equals an optimal value. The strengths of the minimum fields required for Keplerian disk formation in B-type stars varies from order 1G to 10G. In O-type stars they must be of order 500G. Also, we suggest that the stellar magnetic fields may be affected by rotationally driven meridional circulation leading to some of the the observed variations of disks with time.

M. Maheswaran

2003-04-30T23:59:59.000Z

243

Heart-shaped nuclei: Condensation of rotational-aligned octupole phonons  

SciTech Connect (OSTI)

The strong octupole correlations in the mass region A{approx_equal}226 are interpreted as rotation-induced condensation of octupole phonons having their angular momentum aligned with the rotational axis. Discrete phonon energy and parity conservation generate oscillations of the energy difference between the lowest rotational bands with positive and negative parity. Anharmonicities tend to synchronize the rotation of the condensate and the quadrupole shape of the nucleus forming a rotating heart shape.

Frauendorf, S. [ISP, Forschungszentrum Dresden-Rossendorf, Dresden, Germany (Germany); Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

2008-02-15T23:59:59.000Z

244

The Nuclear Born Oppenheimer Method and Nuclear Rotations  

E-Print Network [OSTI]

We deal here with the application of the Nuclear Born Oppenheimer (NBO) method to the description of nuclear rotations. As an edifying illustration, we apply the NBO formalism to study the rotational motion of nuclei which are axially-symmetric and even, but whose shells are not closed. We focus, in particular, on the derivation of expressions for the rotational energy and for the moment of inertia. Additionally, we examine the connection between the NBO method and the self-consistent cranking (SCC) model. Finally, we compare the moment of inertia generated by the NBO method with the Thouless-Valantin formula and hence establish a connection between the NBO method and the large body of experimental data.

Nouredine Zettili

2009-12-27T23:59:59.000Z

245

Nuclear Rotations and the Born-Oppenheimer Approximation  

SciTech Connect (OSTI)

We deal here with the application of the Nuclear Born Oppenheimer (NBO) method to the description of nuclear rotations. As an edifying illustration, we apply the NBO formalism to study the rotational motion of nuclei which are axially-symmetric and even, but whose shells are not closed. We focus, in particular, on the derivation of expressions for the rotational energy and for the moment of inertia. Additionally, we examine the connection between the NBO method and the self-consistent cranking (SCC) model. Finally, we compare the moment of inertia generated by the NBO method with the Thouless-Valantin formula and hence establish a connection between the NBO method and the large body of experimental data.

Zettili, Nouredine [Department of Physical and Earth Sciences, Jacksonville State University, Jacksonville, AL 36265 (United States)

2011-10-27T23:59:59.000Z

246

Ultra high vacuum heating and rotating specimen stage  

DOE Patents [OSTI]

A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1{times}10{sup {minus}9} torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating. 5 figs.

Coombs, A.W. III

1995-05-02T23:59:59.000Z

247

Regenerative braking device with rotationally mounted energy storage means  

DOE Patents [OSTI]

A regenerative braking device for an automotive vehicle includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (30) and an output shaft (32), clutches (50, 56) and brakes (52, 58) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. In a second embodiment the clutches and brakes are dispensed with and the variable ratio transmission is connected directly across the input and output shafts. In both embodiments the rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft rotates faster or relative to the output shaft and are torsionally relaxed to deliver energy to the vehicle when the output shaft rotates faster or relative to the input shaft.

Hoppie, Lyle O. (Birmingham, MI)

1982-03-16T23:59:59.000Z

248

Temporal variations of solar rotation rate at high latitudes  

E-Print Network [OSTI]

Frequency splitting coefficients from Global Oscillation Network Group (GONG) and Michelson Doppler Imager (MDI) observations covering the period 1995--2001 are used to study temporal variations in the solar rotation rate at high latitudes. The torsional oscillation pattern in the Sun is known to penetrate to a depth of about $0.1R_\\odot$ with alternate bands of faster and slower rotating plasma. At lower latitudes the bands move towards equator with time. At higher latitudes, however, the bands appear to move towards the poles. This is similar to the observed pole-ward movement of large scale magnetic fields at high latitudes. This also supports theoretical results of pole-ward moving bands at high latitudes in some mean field dynamo models. The polar rotation rate is found to decrease between 1995 and 1999 after which it has started increasing.

H. M. Antia; Sarbani Basu

2001-08-14T23:59:59.000Z

249

Rapidly rotating neutron stars in $R$-squared gravity  

E-Print Network [OSTI]

$f(R)$ theories of gravity are one of the most popular alternative explanations for dark energy and therefore studying the possible astrophysical implications of these theories is an important task. In the present paper we make a substantial advance in this direction by considering rapidly rotating neutron stars in $R^2$ gravity. The results are obtained numerically and the method we use is non-perturbative and self-consistent. The neutron star properties, such as mass, radius and moment of inertia, are studied in detail and the results show that rotation magnifies the deviations from general relativity and the maximum mass and moment of inertia can reach very high values. This observation is similar to previous studies of rapidly rotating neutron stars in other alternative theories of gravity, such as the scalar-tensor theories, and it can potentially lead to strong astrophysical manifestations.

Yazadjiev, Stoytcho S; Kokkotas, Kostas D

2015-01-01T23:59:59.000Z

250

A nonlinear calculation of rotating cavitation in inducers  

SciTech Connect (OSTI)

In the previous linear analysis (Tsujimoto et al., 1993) it was found that there can be a backward rotating cavitation as well as a forward mode which rotates faster than impeller. Although some shaft vibration has been observed, which might be caused by the backward mode, experimental evidence has been obtained only for the forward mode. The purpose of the present study is to find out the factors which determine the amplitude of each mode of rotating cavitation by taking into account several nonlinearities. A time marching nonlinear 2-D flow analysis was carried out for this purpose. It was found that the increase of cavitation compliance at lower inlet pressure can be a factor which limits the amplitude. The mode selectivity is mainly dependent on the stability limit obtained by a linear analysis for which the phase delay of cavity has a most important effect.

Tsujimoto, Y. [Osaka Univ., Toyonaka, Osaka (Japan). Dept. of Mechanical Engineering]|[National Aerospace Lab., Kakuda, Miyagi (Japan); Watanabe, S.; Yoshida, Y. [Osaka Univ., Toyonaka, Osaka (Japan); Kamijo, K. [National Aerospace Lab., Kakuda, Miyagi (Japan)

1996-09-01T23:59:59.000Z

251

Rigidly rotating ZAMO surfaces in the Kerr spacetime  

E-Print Network [OSTI]

A stationary observer in the Kerr spacetime has zero angular momentum if his/her angular velocity $\\omega$ has a particular value, which depends on the position of the observer. Worldlines of such zero angular momentum observers (ZAMOs) with the same value of the angular velocity $\\omega$ form a three dimensional surface, which has the property that the Killing vectors generating time translation and rotation are tangent to it. We call such a surface a rigidly rotating ZAMO surface. This definition allows a natural generalization to the surfaces inside the black hole, where ZAMO's trajectories formally become spacelike. A general property of such a surface is that there exist linear combinations of the Killing vectors with constant coefficients which make them orthogonal on it. In this paper we discuss properties of the rigidly rotating ZAMO surfaces both outside and inside the black hole and relevance of these objects to a couple of interesting physical problems.

Andrei V. Frolov; Valeri P. Frolov

2014-08-27T23:59:59.000Z

252

Scalar emission in a rotating Gödel black hole  

E-Print Network [OSTI]

We study the absorption probability and Hawking radiation of the scalar field in the rotating G\\"{o}del black hole in minimal five-dimensional gauged supergravity. We find that G\\"{o}del parameter $j$ imprints in the greybody factor and Hawking radiation. It plays a different role from the angular momentum of the black hole in the Hawking radiation and super-radiance. These information can help us know more about rotating G\\"{o}del black holes in minimal five-dimensional gauged supergravity.

Songbai Chen; Bin Wang; Jiliang Jing

2008-08-23T23:59:59.000Z

253

A differential rotation driven dynamo in a stably stratified star  

E-Print Network [OSTI]

We present numerical simulations of a self-sustaining magnetic field in a differentially rotating non-convective stellar interior. A weak initial field is wound up by the differential rotation; the resulting azimuthal field becomes unstable and produces a new meridional field component, which is then wound up anew, thus completing the `dynamo loop'. This effect is observed both with and without a stable stratification. A self-sustained field is actually obtained more easily in the presence of a stable stratification. The results confirm the analytical expectations of the role of Tayler instability.

J. Braithwaite; H. C. Spruit

2005-09-22T23:59:59.000Z

254

Hawking temperature of rotating charged black strings from tunneling  

SciTech Connect (OSTI)

Thermal radiations from spherically symmetric black holes have been studied from the point of view of quantum tunneling. In this paper we extend this approach to study radiation of fermions from charged and rotating black strings. Using WKB approximation and Hamilton-Jacobi method we work out the tunneling probabilities of incoming and outgoing fermions and find the correct Hawking temperature for these objects. We show that in appropriate limits the results reduce to those for the uncharged and non-rotating black strings.

Ahmed, Jamil; Saifullah, K., E-mail: jamil_051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

2011-11-01T23:59:59.000Z

255

Graphene Monolayer Rotation on Ni(111) Facilities Bilayer Graphene Growth  

SciTech Connect (OSTI)

Synthesis of bilayer graphene by chemical vapor deposition is of importance for graphene-based field effect devices. Here, we demonstrate that bilayer graphene preferentially grows by carbon-segregation under graphene sheets that are rotated relative to a Ni(111) substrate. Rotated graphene monolayer films can be synthesized at growth temperatures above 650 C on a Ni(111) thin-film. The segregated second graphene layer is in registry with the Ni(111) substrate and this suppresses further C-segregation, effectively self-limiting graphene formation to two layers.

Batzill M.; Sutter P.; Dahal, A.; Addou, R.

2012-06-11T23:59:59.000Z

256

Spin rotation of polarized beams in high energy storage ring  

E-Print Network [OSTI]

The equations for spin evolution of a particle in a storage ring are obtained considering contributions from the tensor electric and magnetic polarizabilities of the particle along with the contributions from spin rotation and birefringence effect in polarized matter of an internal target. % Study of the spin rotation and birefringence effects for a particle in a high energy storage ring provides for measurement both the spin-dependent real part of the coherent elastic zero-angle scattering amplitude and tensor electric (magnetic) polarizabilities.

V. G. Baryshevsky

2006-03-23T23:59:59.000Z

257

Study of the subpicosecond rotational molecular dynamics in liquids  

SciTech Connect (OSTI)

The parameters of the femtosecond vibration-rotation molecular dynamics of liquid acetonitrile CH{sub 3}CN, trimethylacetonitrile (CH{sub 3}){sub 3}CCN, propionitrile CH{sub 3}CH{sub 2}CN, fluoroform CHF{sub 3}, and chloroform CHCl{sub 3} are found by analysing the ultrafast optical Kerr effect. The influence of the molecular structure on the features of rotational (diffusion and libration) motions is studied. It is shown that the distribution of libration frequencies is described by the Maxwell distribution. (laser applications and other topics in quantum electronics)

Nikiforov, V G; Lobkov, Vladimir S [E.K.Zavoisky Physical-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, Kazan (Russian Federation)

2006-10-31T23:59:59.000Z

258

The solar interior - radial structure, rotation, solar activity cycle  

E-Print Network [OSTI]

Some basic properties of the solar convection zone are considered and the use of helioseismology as an observational tool to determine its depth and internal angular velocity is discussed. Aspects of solar magnetism are described and explained in the framework of dynamo theory. The main focus is on mean field theories for the Sun's magnetic field and its differential rotation.

Axel Brandenburg

2007-03-28T23:59:59.000Z

259

Solar differential rotation and properties of magnetic clouds  

E-Print Network [OSTI]

The most geoeffective solar drivers are magnetic clouds - a subclass of coronal mass ejections (CME's) distinguished by the smooth rotation of the magnetic field inside the structure. The portion of CME's that are magnetic clouds is maximum at sunspot minimum and mimimum at sunspot maximum. This portion is determined by the amount of helicity carried away by CME's which in turn depends on the amount of helicity transferred from the solar interior to the surface, and on the surface differential rotation. The latter can increase or reduce, or even reverse the twist of emerging magnetic flux tubes, thus increasing or reducing the helicity in the corona, or leading to the violation of the hemispheric helicity rule, respectively. We investigate the CME's associated with the major geomagnetic storms in the last solar cycle whose solar sources have been identified, and find that in 10 out of 12 cases of violation of the hemispheric helicity rule or of highly geoeffective CME's with no magnetic field rotation, they originate from regions with "anti-solar" type of surface differential rotation.

K. Georgieva; B. Kirov; E. Gavruseva; J. Javaraiah

2005-11-09T23:59:59.000Z

260

Dual periodicities in the rotational modulation of Saturn narrowband emissions  

E-Print Network [OSTI]

Dual periodicities in the rotational modulation of Saturn narrowband emissions S.Y. Ye,1 D. A emissions is examined, restricting the spacecraft location to either the northern or the southern hemisphere of Saturn. It is found that in both hemispheres, the modulation period of 5 kHz narrowband emissions has two

Gurnett, Donald A.

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Complex dynamics in a short annular container with rotating bottom ...  

E-Print Network [OSTI]

We believe that these phenomena are novel in fluid dynamics, as is a ... outer radius Ro and length L, driven by the constant rotation of the inner cylinder and bottom .... Poisson-like equations are solved using the spectral–Galerkin method presented in ... is a multiplicity of states over a small range of ? ? (2.8635, 2.

2004-02-10T23:59:59.000Z

262

Energy and Momentum of a Class of Rotating Gravitational Waves  

E-Print Network [OSTI]

We calculate energy and momentum for a class of cylindrical rotating gravitational waves using Einstein and Papapetrou's prescriptions. It is shown that the results obtained are reduced to the special case of the cylindrical gravitational waves already available in the literature.

M. Sharif

2001-02-09T23:59:59.000Z

263

Spin-rotation coupling in compound spin objects  

E-Print Network [OSTI]

We generalize spin-rotation coupling to compound spin systems. In the case of muons bound to nuclei in a storage ring the decay process acquires a modulation. Typical frequencies for $Z/A\\sim 1/2$ are $\\sim 3\\times 10^6$Hz, a factor 10 higher than the modulation observed in $g-2$ experiments.

G. Lambiase; G. Papini

2013-01-31T23:59:59.000Z

264

Rotational Spectroscopy of PAHs: Acenaphthene, Acenaphthylene and Fluorene  

E-Print Network [OSTI]

Pure rotational spectra of three polycyclic aromatic hydrocarbons - acenaphthene, acenaphthylene and fluorene - have been obtained by Fourier transform microwave spectroscopy of a molecular beam and subsequently by millimeter wave absorption spectroscopy for acenaphthene and fluorene. The data presented here will be useful for deep radio astronomical searches for PAHs employing large radio telecopes.

Thorwirth, S; Gottlieb, C A; McCarthy, M C; Thaddeus, P

2005-01-01T23:59:59.000Z

265

Rotational Spectroscopy of PAHs: Acenaphthene, Acenaphthylene and Fluorene  

E-Print Network [OSTI]

Pure rotational spectra of three polycyclic aromatic hydrocarbons - acenaphthene, acenaphthylene and fluorene - have been obtained by Fourier transform microwave spectroscopy of a molecular beam and subsequently by millimeter wave absorption spectroscopy for acenaphthene and fluorene. The data presented here will be useful for deep radio astronomical searches for PAHs employing large radio telecopes.

S. Thorwirth; P. Theule; C. A. Gottlieb; M. C. McCarthy; P. Thaddeus

2005-09-23T23:59:59.000Z

266

Rotation-reversal symmetries in crystals and handed structures  

E-Print Network [OSTI]

: List of roto point groups indicated in Figure 2b that are invariance groups of a net (non-zero) spin (S of roto point groups indicated in Figure 2b that are invariance groups of non-zero (net) spin (S), non-zero (net) electric polarization (P), non-zero (net) static rotation (), and combinations thereof. Net Spin

Gopalan, Venkatraman

267

A rotating suspended liquid film as an electric generator  

E-Print Network [OSTI]

We have observed that a rotating liquid film generates electricity when a large external electric field is applied in the plane of the film. In our experiment suspended liquid film (soap film) is formed on a circular frame positioned horizontally on a rotating motor. This devise is located at the center of two capacitor-like vertical plates to apply external electric field in X-direction.The produced electric energy is piked up by two brushes in Y-direction of the suspended liquid film. We previously reported that a liquid film in an external electric field rotates when an electric current passes through it, naming it the liquid film motor (LFM). In this letter we report that the same system can be used as an electric generator, converting the rotating mechanical energy to an electric energy. The liquid film electric generator (LFEG) is in stark contrast to the LFM, both of which could be designed in very small scales like micro scales applicable in lab on a chip. The device is comparable to commercial DC ele...

Amjadi, Ahmad; Namin, Reza Montazeri

2013-01-01T23:59:59.000Z

268

ECG Gated Tomographic reconstruction for 3-D Rotational Coronary Angiography  

E-Print Network [OSTI]

imaging techniques to improve both the safety and the efficacy of coronary angiography interventions the ground for a platform dedicated to the planning and execution of percutaneous coronary inter- ventionsECG Gated Tomographic reconstruction for 3-D Rotational Coronary Angiography Yining HU, Lizhe XIE

Paris-Sud XI, Université de

269

Cryogenic cooling with cryocooler on a rotating system  

E-Print Network [OSTI]

We developed a system that continuously maintains a cryocooler for long periods on a rotating table. A cryostat that holds the cryocooler is set on the table. A compressor is located on the ground and supplies high-purity (> 99.999%) and high-pressure (1.7 MPa) helium gas and electricity to the cryocooler. The operation of the cryocooler and other instruments requires the development of interface components between the ground and rotating table. A combination of access holes at the center of the table and two rotary joints allows simultaneous circulation of electricity and helium gas. The developed system provides two innovative functions under the rotating condition; cooling from room temperature and the maintenance of a cold condition for long periods. We have confirmed these abilities as well as temperature stability under a condition of continuous rotation at 20 revolutions per minute. The developed system can be applied in various fields; e.g., in tests of Lorentz invariance, searches for axion, radio as...

Oguri, Shugo; Kawai, Masanori; Tajima, Osamu

2013-01-01T23:59:59.000Z

270

Quantum rotation of hydrogen in single-wall carbon nanotubes  

E-Print Network [OSTI]

Quantum rotation of hydrogen in single-wall carbon nanotubes C.M. Brown a,b , T. Yildirim b , D containing single-wall carbon nanotubes. These materials have attracted considerable interest recently due the ortho±para conversion of physisorbed hydrogen in a nanotube containing soot loaded with hydrogen. From

Yildirim, Taner

271

RECURSIVELY RENEWABLE WORDS AND CODING OF IRRATIONAL ROTATIONS  

E-Print Network [OSTI]

RECURSIVELY RENEWABLE WORDS AND CODING OF IRRATIONAL ROTATIONS SHIGEKI AKIYAMA AND MASAYUKI us come back to a general A = {0, 1, . . . , m - 1}. An element z = z0z1 · · · AN is k-renewable is called recursively k-renewable. To be more precise, z = z0z1 . . . is recursively k- renewable when

Akiyama, Shigeki

272

Supercritical rotating flow over topography J. G. Esler,a  

E-Print Network [OSTI]

wind field.1­3 Trapped waves can be resonantly excited by topographic forcing, leading, strong nonlinearities are displaced to the wake regions at the flanks of the obstacle. In the presence of weak rotation and for small obstacle height the development of the nonlinear wakes is governed

Esler, Gavin

273

Electrostatic Interchange Instabilities of a Rotating, High-Temperature Plasma  

E-Print Network [OSTI]

Electrostatic Interchange Instabilities of a Rotating, High-Temperature Plasma Confined by a Dipole #2 Mach Probe #1 Mach Probe #2 High-field, 0.2 MA-turn Water-cooled Magnet #12;Interchange Modes-sized/global... Fast hot electron interchange instability: drift-resonant transport; Gryokinetics; phase-space holes

Mauel, Michael E.

274

Rotating Target Development for SNS Second Target Station  

SciTech Connect (OSTI)

A rotating target for the second target station (STS) at SNS has been identified as an option along with a mercury target. Evaluation of the rotating target alternative for STS has started at 1.5 MW which is considered an upper bound for the power. Previous preconceptual design work for a 3 MW rotating target is being modified for the lower power level. Transient thermal analysis for a total loss of active water cooling has been done for a simplified 2D model of the target and shielding monolith which shows that peak temperatures are well below the level at which tungsten vaporization by steam could exceed site boundary dose limits. Design analysis and integration configuration studies have been done for the target-moderator-reflector assembly which maximizes the number of neutron beam lines and provides for replacement of the target and moderators. Target building hot cell arrangement for this option will be described. An option for operation in rough vacuum without a proton beam window using Ferro fluid seals on a vertical shaft is being developed. A full scale prototypic drive module based on the 3 MW preconceptual design has been fabricated and successfully tested with a shaft and mock up target supplied by the ESS-Bilbao team. Overall planning leading to decision between mercury and the rotating target in 2011 will be discussed

McManamy, Thomas J [ORNL; Rennich, Mark J [ORNL; Crawford, Roy K [ORNL; Geoghegan, Patrick J [ORNL; Janney, Jim G [ORNL

2010-01-01T23:59:59.000Z

275

Asynchronous Control of Rotation and Translation for a Robot Vehicle  

E-Print Network [OSTI]

Cartesian coordinate space. In the same sense, robot vehicles require a "vehicle controller" to commandAsynchronous Control of Rotation and Translation for a Robot Vehicle James L. Crowley Patrick Appeared in Journal of Robotics and Autonomous Systems February 1993 © 1992 James L. Crowley This work has

Crowley, James L.

276

Effect of spin rotation coupling on spin transport  

SciTech Connect (OSTI)

We have studied the spin rotation coupling (SRC) as an ingredient to explain different spin-related issues. This special kind of coupling can play the role of a Dresselhaus like coupling in certain conditions. Consequently, one can control the spin splitting, induced by the Dresselhaus like term, which is unusual in a semiconductor heterostructure. Within this framework, we also study the renormalization of the spin-dependent electric field and spin current due to the k{sup ?}?p{sup ?} perturbation, by taking into account the interband mixing in the rotating system. In this paper we predict the enhancement of the spin-dependent electric field resulting from the renormalized spin rotation coupling. The renormalization factor of the spin electric field is different from that of the SRC or Zeeman coupling. The effect of renormalized SRC on spin current and Berry curvature is also studied. Interestingly, in the presence of this SRC-induced SOC it is possible to describe spin splitting as well as spin galvanic effect in semiconductors. -- Highlights: •Studied effect of spin rotation coupling on the spin electric field, spin current and Berry curvature. •In the k{sup ?}?p{sup ?} framework we study the renormalization of spin electric field and spin current. •For an inertial system we have discussed the spin splitting. •Expression for the Berry phase in the inertial system is discussed. •The inertial spin galvanic effect is studied.

Chowdhury, Debashree, E-mail: debashreephys@gmail.com; Basu, B., E-mail: sribbasu@gmail.com

2013-12-15T23:59:59.000Z

277

ROTATION OF WHITE LIGHT CME STRUCTURES AS INFERRED FROM  

E-Print Network [OSTI]

field, and it could shed light on the problems related to connecting solar surface phenomenaROTATION OF WHITE LIGHT CME STRUCTURES AS INFERRED FROM LASCO CORONAGRAPH Vasyl Yurchyshyn Big Bear Solar Observatory 40386 North Shore Lane, Big Bear City, CA 92314 Valentyna Abramenko Big Bear Solar

278

Mechanical Inhibition of Foam Formation via a Rotating Nozzle  

E-Print Network [OSTI]

have been devel- oped to minimize the impact of foams [2]. Anti-foaming agents are added to prevent environmental disposal problems, and increase the overall process cost and complexity [3]. Non report a design for a rotating nozzle that prevents successive collocated impacts, thereby minimizing

Ristenpart, William

279

BLACK HOLE AURORA POWERED BY A ROTATING BLACK HOLE  

SciTech Connect (OSTI)

We present a model for high-energy emission sources generated by a standing magnetohydrodynamical (MHD) shock in a black hole magnetosphere. The black hole magnetosphere would be constructed around a black hole with an accretion disk, where a global magnetic field could be originated by currents in the accretion disk and its corona. Such a black hole magnetosphere may be considered as a model for the central engine of active galactic nuclei, some compact X-ray sources, and gamma-ray bursts. The energy sources of the emission from the magnetosphere are the gravitational and electromagnetic energies of magnetized accreting matters and the rotational energy of a rotating black hole. When the MHD shock generates in MHD accretion flows onto the black hole, the plasma's kinetic energy and the black hole's rotational energy can convert to radiative energy. In this Letter, we demonstrate the huge energy output at the shock front by showing negative energy postshock accreting MHD flows for a rapidly rotating black hole. This means that the extracted energy from the black hole can convert to the radiative energy at the MHD shock front. When an axisymmetric shock front is formed, we expect a ring-shaped region with very hot plasma near the black hole; this would look like an 'aurora'. The high-energy radiation generated from there would carry to us the information for the curved spacetime due to the strong gravity.

Takahashi, Masaaki [Department of Physics and Astronomy, Aichi University of Education, Kariya, Aichi 448-8542 (Japan); Takahashi, Rohta, E-mail: takahasi@phyas.aichi-edu.ac.j [Cosmic Radiation Laboratory, Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

2010-05-15T23:59:59.000Z

280

Rotation of the Sacrum During Bellyboard Pelvic Radiotherapy  

SciTech Connect (OSTI)

Patients with cervical, uterine, and rectal carcinomas are usually treated in the prone position using the bellyboard positioning device. Specific and uncomfortable prone position gives rise to uncertainties in the daily set-up of patients during the treatment. During investigation of translational movements, rotational movements of the pelvis are observed and investigated. The film portal imaging is used to discover patient positioning errors during treatment. We defined the rotational set-up errors by angle deviations of the sacrum. Thirty-six patients were included in the study; 15 patients were followed during the whole treatment and 21 during the first 5 consecutive treatment days. The image acquisitions were completed in 84%. Systematic and random positioning errors were analyzed in 725 images. Approximately half of the patients had adjusted to the bellyboard in the first few fractions, with sacrum angles remaining the same for the rest of the treatment. The other half had drifts of the sacrum angle during the whole treatment. The rotation of the sacrum during treatment ranged up to 14 deg., causing the usual set-up verification and correction procedure to result in errors up to 15 mm. Rotational movements of the patient pelvis during bellyboard pelvis radiotherapy can introduce considerable patient position error.

Kasabasic, Mladen [Radiotherapy and Oncology Department, University Hospital of Osijek, Osijek (Croatia)], E-mail: mkasabasic@mefos.hr; Faj, Dario; Ivkovic, Ana; Jurkovic, Slaven; Belaj, Nenad [Radiotherapy and Oncology Department, University Hospital of Osijek, Osijek (Croatia)

2010-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Rotational and divergent kinetic energy in the mesoscale model ALADIN  

E-Print Network [OSTI]

energy, divergent energy, ALADIN, limited-area modelling 1. Introduction Horizontal divergenceRotational and divergent kinetic energy in the mesoscale model ALADIN By V. BLAZ ICA1 *, N. Z AGAR1 received 7 June 2012; in final form 7 March 2013) ABSTRACT Kinetic energy spectra from the mesoscale

Zagar, Nedjeljka

282

Influence of Rotations on the Critical State of Soil Mechanics  

E-Print Network [OSTI]

The ability of grains to rotate can play a crucial role on the collective behavior of granular media. It has been observed in computer simulations that imposing a torque at the contacts modifies the force chains, making support chains less important. In this work we investigate the effect of a gradual hindering of the grains rotations on the so-called critical state of soil mechanics. The critical state is an asymptotic state independent of the initial solid fraction where deformations occur at a constant shear strength and compactness. We quantify the difficulty to rotate by a friction coefficient at the level of particles, acting like a threshold. We explore the effect of this particle-level friction coefficient on the critical state by means of molecular dynamics simulations of a simple shear test on a poly-disperse sphere packing. We found that the larger the difficulty to rotate, the larger the final shear strength of the sample. Other micro-mechanical variables, like the structural anisotropy and the di...

Oquendo, W F; Lizcano, A

2010-01-01T23:59:59.000Z

283

Solar activity and earth rotation variability R. Abarca del Rioa,  

E-Print Network [OSTI]

to secular times scales, meteorological and climatic data are correlated with solar variability (see reviews changes in solar output could be amplified in the Earth's atmosphere. In fact, at wavelengths not visibleSolar activity and earth rotation variability R. Abarca del Rioa, *, D. Gambisb , D. Salsteinc , P

Dai, Aiguo

284

Thermodynamical properties of a rotating ideal Bose gas Sebastian Kling*  

E-Print Network [OSTI]

potential becomes sombrero shaped. We present an analysis for an ideal Bose gas that is confined and determine the criti- cal temperature, the condensate fraction, and the heat capac- ity of the Bose gasThermodynamical properties of a rotating ideal Bose gas Sebastian Kling* Institut für Angewandte

Pelster, Axel

285

Logarithmic Bounds for Infinite Prandtl Number Rotating Convection  

E-Print Network [OSTI]

is how much of the total heat transfer is due to convec- tion. The natural measure of this quantity on the forcing parameter [1] - [6], although it has been observed that rotation plays a nontrivial role as well, Chandrasekhar [8]). This is a 1 #12; system of equations coupling

Constantin, Peter

286

Multi-Touch Rotation Gestures: Performance and Ergonomics  

E-Print Network [OSTI]

Multi-Touch Rotation Gestures: Performance and Ergonomics Eve Hoggan1 , John Williamson2 , Antti multi-touch gestures, yet little is known about the fac- tors affecting performance and ergonomics; gestures; ergonomics. ACM Classification Keywords H.5.2. User Interfaces: Evaluation/Methodology, Input De

287

Feedback on vertical velocity. Rotation, convection, self-sustaining process.  

E-Print Network [OSTI]

Feedback on vertical velocity. Rotation, convection, self-sustaining process. Fabian Waleffe the mechanisms involved in the nonlinear feedback from u to v, yielding a self-sustaining process for shear flows feedback from the streak instability into the rolls sufficient to lead to a self-sustaining process

Lebovitz, Norman

288

Wigner representation of the rotational dynamics of rigid tops  

E-Print Network [OSTI]

We propose the general methodology to design the Wigner representations with the desired dynamical and semiclassical properties in the phase spaces with nontrivial topology. As an illustration, two representations of molecular rotations are developed to suit the computational demands of contemporary applications of laser alignment, diagnostics of reaction dynamics, studies of scattering and dissipative processes.

Dmitry V. Zhdanov; Tamar Seideman

2014-06-15T23:59:59.000Z

289

CONVERVATION OF ANGULAR MOMENTUM A rotating bicycle wheel has angular  

E-Print Network [OSTI]

CONVERVATION OF ANGULAR MOMENTUM A rotating bicycle wheel has angular momentum, which is a property of a bicycle wheel's mass is concentrated along the wheel's rim, rather than at the center, and this causes. The bicycle wheel, you, and the chair comprise a system that obeys the principle of conservation of angular

290

Effect of rotating electric field on 3D complex (dusty) plasma  

SciTech Connect (OSTI)

The effect of rotating electric field on 3D particle clusters suspended in rf plasma was studied experimentally. Spheroidal clusters were suspended inside a glass box mounted on the lower horizontal rf electrode, with gravity partially balanced by thermophoretic force. Clusters rotated in the horizontal plane, in response to rotating electric field that was created inside the box using conducting coating on its inner surfaces (''rotating wall'' technique). Cluster rotation was always in the direction of applied field and had a shear in the vertical direction. The angular speed of rotation was 10{sup 4}-10{sup 7} times lower than applied frequency. The experiment is compared to a recent theory.

Woerner, L.; Nosenko, V.; Ivlev, A. V.; Zhdanov, S. K.; Thomas, H. M.; Morfill, G. E. [Max-Planck-Institut fuer extraterrestrische Physik, D-85741 Garching (Germany); Kroll, M.; Schablinski, J.; Block, D. [Christian-Albrechts Universitaet zu Kiel, D-24118 Kiel (Germany)

2011-06-15T23:59:59.000Z

291

Ferrofluid spin-up flows from uniform and non-uniform rotating magnetic fields  

E-Print Network [OSTI]

When ferrofluid in a cylindrical container is subjected to a rotating azimuthally directed magnetic field, the fluid "spins up" into an almost rigid-body rotation where ferrofluid nanoparticles have both a linear and an ...

Khushrushahi, Shahriar Rohinton

2010-01-01T23:59:59.000Z

292

The application of eccentric rotating cylinder apparatus for the improved study of particle coagulation  

E-Print Network [OSTI]

Concentric rotating cylinder and turbulent mixing devices have been frequently used in studying mixing and particle coagulation. However, these apparatus develop simple laminar flow (concentric rotating cylinders) or do not have well-defined flow...

Lee, Chun Woo

2004-11-15T23:59:59.000Z

293

Nonlinear gyrokinetic simulations of intrinsic rotation in up-down asymmetric tokamaks  

E-Print Network [OSTI]

Experiments and theory show that tokamak plasmas with strong toroidal rotation and rotation shear can suppress turbulent energy transport as well as allow violation of the Troyon [beta] limit. However, using external neutral ...

Ball, Justin Richard

2013-01-01T23:59:59.000Z

294

Analysis of the rotational structure in the high-resolution infrared...  

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

rotational structure in the high-resolution infrared spectra of cis,cis- and trans,trans-1,4-difluorobutadiene-1 Analysis of the rotational structure in the high-resolution...

295

Analysis of the Rotational Structure in the High-Resolution Infrared...  

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

Rotational Structure in the High-Resolution Infrared Spectrum of trans-Hexatriene-1-13C1; a Semiexperimental Analysis of the Rotational Structure in the High-Resolution Infrared...

296

Comparison of chemically-enhanced phytoextraction by arable crops and short rotation coppice with  

E-Print Network [OSTI]

Comparison of chemically-enhanced phytoextraction by arable crops and short rotation coppice biomass arable crops, and the use of short rotation coppice species (McGrath et al., 2001). Although much

Crout, Neil

297

The behavior of rotator cuff tendon cells in three-dimensional culture  

E-Print Network [OSTI]

The rotator cuff is composed of the supraspinatus, infraspinatus, subcapularis, and teres minor tendons. Rotator cuff injuries are common athletic and occupational injuries that surgery cannot fully repair. Therefore tendon ...

Gill, Harmeet (Harmeet Kaur)

2007-01-01T23:59:59.000Z

298

Eye Movements During Multi-Axis Whole-Body Rotations CHRISTOPHER J. BOCKISCH,1  

E-Print Network [OSTI]

Straumann, and Thomas Hasl- wanter. Eye movements during multi-axis whole-body rotations. J Neurophysiol 89

Haslwanter, Thomas

299

E-Print Network 3.0 - alternately rotating walls Sample Search...  

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

Background The rotating cone setup 15 Stability analysis Results Application: Spinning missile Source: Collection: Mathematics 50 Engineering Nanomotor Components from...

300

Possible Measurable Effects of Dark Energy in Rotating Superconductors  

E-Print Network [OSTI]

We discuss recent laboratory experiments with rotating superconductors and show that three so far unexplained experimentally observed effects (anomalous acceleration signals, anomalous gyroscope signals, Cooper pair mass excess) can be physically explained in terms of a possible interaction of dark energy with Cooper pairs. Our approach is based on a Ginzburg-Landau-like model of electromagnetic dark energy, where gravitationally active photons obtain mass in the superconductor. We show that this model can account simultaneously for the anomalous acceleration and anomalous gravitomagnetic fields around rotating superconductors measured by Tajmar et al. and for the anomalous Cooper pair mass in superconductive Niobium, measured by Cabrera and Tate. It is argued that these three different physical effects are ultimately different experimental manifestations of the simultaneous spontaneous breaking of gauge invariance, and of the principle of general covariance in superconductive materials.

Clovis Jacinto de Matos; Christian Beck

2007-07-12T23:59:59.000Z

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


301

ROTATION CURVES OF 967 SPIRAL GALAXIES: IMPLICATIONS FOR DARK MATTER.  

E-Print Network [OSTI]

We present the rotation curves of 967 spiral galaxies, obtained by deprojecting and folding the raw data published by Mathewson et al. (1992). Of these, 80 meet objective excellence criteria and are suitable for individual detailed mass modelling, while 820 are suitable for statistical studies. A preliminary analysis of theire properties confirms that rotation curves are a universal function of luminosity and that the dark matter fraction in spirals increase with decreasing luminosity. Quantitative considerations on the virial radius of dark halos allow us to make hypotheses about their structure and nature. The deprojected folded curves, the smoothed curves, and various related quantities are available via anonymous ftp at ftp://galileo.sissa.it/users/ftp/pub/psrot

Massimo Persic; Paolo Salucci; Fulvio Stel

1995-03-13T23:59:59.000Z

302

A Fokker-Planck Model of Rotating Stellar Clusters  

E-Print Network [OSTI]

We have developed a two-dimensional orbit averaged Fokker-Planck model of stellar clusters which expands on spherically symmetric one-dimensional models to include rotation and ellipticity. Physical effects such as collisions, finite stellar lifetimes and bar formation (i.e., a non-axisymmetric component of the potential) can also be included. The first use of the model is to study the evolution of dense clusters (rho(r=0)=~10^7 M_sun/pc^3) that may be expected to have existed at the centres of newly-forming galaxies, with the goal of verifying that angular momentum can be removed from the core of the cluster quickly enough so that rotation no longer prevents the formation of a massive (~10^2 M_sun) object. This could act as the seed black hole for the formation of an AGN.

J. Girash

1997-04-05T23:59:59.000Z

303

Electron beam machining using rotating and shaped beam power distribution  

DOE Patents [OSTI]

An apparatus and method are disclosed for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: (1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and (2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1,000 {micro}m (1 mm or larger), compared to the 250 {micro}m diameter of laser drilling. 5 figs.

Elmer, J.W.; O`Brien, D.W.

1996-07-09T23:59:59.000Z

304

Electron beam machining using rotating and shaped beam power distribution  

DOE Patents [OSTI]

An apparatus and method for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: 1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and 2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1000 .mu.m (1 mm or larger), compared to the 250 .mu.m diameter of laser drilling.

Elmer, John W. (Pleasanton, CA); O'Brien, Dennis W. (Livermore, CA)

1996-01-01T23:59:59.000Z

305

PIC simulation of electrodeless plasma thruster with rotating electric field  

SciTech Connect (OSTI)

For longer lifetime of electric propulsion system, an electrodeless plasma thruster with rotating electric field have been proposed utilizing a helicon plasma source. The rotating electric field may produce so-called Lissajous acceleration of helicon plasma in the presence of diverging magnetic field through a complicated mechanism originating from many parameters. Two-dimensional simulations of the Lissajous acceleration were conducted by a code based on Particle-In-Cell (PIC) method and Monte Carlo Collision (MCC) method for understanding plasma motion in acceleration area and for finding the optimal condition. Obtained results show that azimuthal current depends on ratio of electron drift radius to plasma region length, AC frequency, and axial magnetic field. When ratio of cyclotron frequency to the AC frequency is higher than unity, reduction of the azimuthal current by collision effect is little or nothing.

Nomura, Ryosuke; Ohnishi, Naofumi; Nishida, Hiroyuki [Department of Aerospace Engineering, Tohoku University, Sendai 980-8579 (Japan); Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo 184-8588 (Japan)

2012-11-27T23:59:59.000Z

306

Prototype Spallation Neutron Source Rotating Target Assembly Final Test Report  

SciTech Connect (OSTI)

A full-scale prototype of an extended vertical shaft, rotating target assembly based on a conceptual target design for a 1 to 3-MW spallation facility was built and tested. Key elements of the drive/coupling assembly implemented in the prototype include high integrity dynamic face seals, commercially available bearings, realistic manufacturing tolerances, effective monitoring and controls, and fail-safe shutdown features. A representative target disk suspended on a 3.5 meter prototypical shaft was coupled with the drive to complete the mechanical tests. Successful operation for 5400 hours confirmed the overall mechanical feasibility of the extended vertical shaft rotating target concept. The prototype system showed no indications of performance deterioration and the equipment did not require maintenance or relubrication.

McManamy, Thomas J [ORNL; Graves, Van [Oak Ridge National Laboratory (ORNL); Garmendia, Amaia Zarraoa [IDOM Bilbao; Sorda, Fernando [ESS Bilbao; Etxeita, Borja [IDOM Bilbao; Rennich, Mark J [ORNL

2011-01-01T23:59:59.000Z

307

Rotating BTZ Black Holes and One Dimensional Holographic Superconductors  

E-Print Network [OSTI]

We consider charged rotating BTZ black holes in 2+1 dimensions and obtain 1+1 dimensional holographic superconductors on a spatial circle in the context of the $AdS_3/CFT_2$ correspondence. The charged condensate for the boundary superconductor is computed both in the analytic and the numerical framework in a probe limit and a low angular momentum approximation. A critical value of the angular momentum for the onset of superconductivity is established. We also numerically compute the electrical conductivity of the 1+1 dimensional boundary theory on a circle. The conductivity exhibits a dependence on angular momentum of the rotating black hole both for the normal and the superconducting phase of the boundary field theory. The significance of the boundary field theory in the context of a Fermi-Luttinger liquid on a circle is discussed.

Pankaj Chaturvedi; Gautam Sengupta

2014-06-30T23:59:59.000Z

308

On rotational dynamics of an NH4+ ion in water  

SciTech Connect (OSTI)

We used molecular dynamics simulations to characterize the rotational dynamics of the NH4+ ion in liquid water. The polarizable potential models were to describe the ion-water and water-water interactions. This study complements the work of Karim and Haymet (J. Chem. Phys., 93, 5961, 1990), who employed effective pir potential models. The computed rotational diffusion coefficients of the NH4+ ion in water, which were determined from the angular momentum autocorrelation function and the angular mean-square displacement, are 0.093 x 1012 rad2/s and 0.067 x 1012 rad2/s, repectively. These results are in good agreement with the 0.075 x 1012 rad2/s value determined from the nuclear magnetic resonance (NMR) spectroscopy studies of Perrin and Gipe (J. Am. Chem. Soc., 108, 1088, 1986; Science, 238, 1393, 1987).

Chang, Tsun-Mei (University of Wisconsin-Parkside); Dang, Liem X. (BATTELLE (PACIFIC NW LAB))

2003-05-15T23:59:59.000Z

309

Dual annular rotating "windowed" nuclear reflector reactor control system  

DOE Patents [OSTI]

A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core.

Jacox, Michael G. (Idaho Falls, ID); Drexler, Robert L. (Idaho Falls, ID); Hunt, Robert N. M. (Idaho Falls, ID); Lake, James A. (Idaho Falls, ID)

1994-01-01T23:59:59.000Z

310

Aerodynamic testing of a rotating wind turbine blade  

SciTech Connect (OSTI)

Aerodynamic, load, flow-visualization, and inflow measurements were taken on a downwind horizontal-axis wind turbine (HAWT). A video camera mounted on the rotor recorded video images of tufts attached to the low-pressure side of the blade. Strain gages, mounted every 10% of the blade's span, provided load and pressure measurements. Pressure taps at 32 chordwise positions recorded pressure distributions. Wind inflow was measured via a vertical-plane array of anemometers located 10 m upwind. The objectives of the test were to address whether airfoil pressure distributions measured on a rotating blade differed from those measured in the wind tunnel, if radial flow near or in the boundary layer of the airfoil affected pressure distributions, if dynamic stall could result in increased dynamic loads, and if the location of the separation boundary measured on the rotating blade agreed with that measured in two-dimensional flow in the wind tunnel. 6 refs., 9 figs., 1 tab.

Butterfield, C.P.; Nelsen, E.N.

1990-01-01T23:59:59.000Z

311

The Age and Interior Rotation of Stars from Asteroseismology  

E-Print Network [OSTI]

We provide a status report on the determination of stellar ages from asteroseismology for stars of various masses and evolutionary stages. The ability to deduce the ages of stars with a relative precision of typically 10 to 20% is a unique opportunity for stellar evolution and also of great value for both galactic and exoplanet studies. Further, a major uncalibrated ingredient that makes stellar evolution models uncertain, is the stellar interior rotation frequency $\\Omega(r)$ and its evolution during stellar life. We summarize the recent achievements in the derivation of $\\Omega(r)$ for different types stars, offering stringent observational constraints on theoretical models. Core-to-envelope rotation rates during the red giant stage are far lower than theoretical predictions, pointing towards the need to include new physical ingredients that allow strong and efficient coupling between the core and the envelope in the models of low-mass stars in the evolutionary phase prior to the core helium burning. Stars ...

Aerts, Conny

2015-01-01T23:59:59.000Z

312

Cosmic Polarization Rotation: an Astrophysical Test of Fundamental Physics  

E-Print Network [OSTI]

Possible violations of fundamental physical principles, e.g. the Einstein Equivalence Principle on which all metric theories of gravity are based, including General Relativity, would lead to a rotation of the plane of polarization for linearly polarized radiation traveling over cosmological distances, the so-called cosmic polarization rotation (CPR). We review here the astrophysical tests which have been carried out so far to check if CPR exists. These are using the radio and UV polarization of radio galaxies and the polarization of the cosmic microwave background (both E-mode and B-mode). These tests so far have been negative, leading to upper limits of the order of one degree on any CPR angle, thereby increasing our confidence in those physical principles, including General Relativity. We also discuss future prospects in detecting CPR or improving the constraints on it.

Alighieri, Sperello di Serego

2015-01-01T23:59:59.000Z

313

MAGNETIC FIELDS AND THE OUTER ROTATION CURVE OF M31  

SciTech Connect (OSTI)

Recent observations of the rotation curve of M31 show a rise of the outer part that cannot be understood in terms of standard dark matter models or perturbations of the galactic disk by M31's satellites. Here, we propose an explanation of this dynamical feature based on the influence of the magnetic field within the thin disk. We have considered standard mass models for the luminous mass distribution, a Navarro-Frenk-White model to describe the dark halo, and we have added up the contribution to the rotation curve of a magnetic field in the disk, which is described by an axisymmetric pattern. Our conclusion is that a significant improvement of the fit in the outer part is obtained when magnetic effects are considered. The best-fit solution requires an amplitude of {approx}4 {mu}G with a weak radial dependence between 10 and 38 kpc.

Ruiz-Granados, B.; Rubino-Martin, J. A. [Instituto de Astrofisica de Canarias (IAC), E-38200, La Laguna, Tenerife (Spain); Florido, E.; Battaner, E. [Departamento Fisica Teorica y del Cosmos, Universidad de Granada, Granada (Spain)

2010-11-01T23:59:59.000Z

314

Waves and Mirror Symmetry in Rotating and Stratified Turbulence Pablo D. Mininni  

E-Print Network [OSTI]

Waves and Mirror Symmetry in Rotating and Stratified Turbulence Pablo D. Mininni Departamento de in a flow. In ideal rotating flows, helicity is conserved, and waves in rotating and stratified flows are associated with helical flows, to the point that helical-wave decompositions are often used to study

315

Channeling in a Rotating Plasma Abraham J. Fetterman and Nathaniel J. Fisch  

E-Print Network [OSTI]

of the -channeling effect, where injected wave energy can be amplified at the expense of the -particle energy energy, in addition to amplifying the rf waves, can directly enhance the rotation energy which in turn at the rotation velocity in the rotating frame. Lately there has been a renewed interest in this effect [4

316

Vortex-peak interaction and lattice shape in rotating two-component Bose-Einstein condensates  

E-Print Network [OSTI]

Vortex-peak interaction and lattice shape in rotating two-component Bose-Einstein condensates: November 28, 2011) When a two component Bose-Einstein condensate is placed into rotation, a lattice component condensate is set into rotation, topological defects of both order parameters are created, which

Wei, Jun-cheng

317

The pure rotational spectrum of NaC in its X 4 state: Observation  

E-Print Network [OSTI]

on metal carbides is now available from electronic spectro- scopy5­15 and more recently, from rotational rotational transitions were measured in the frequency range from 231 (N 98) to 539 GHz (N 2120). The quartet fine structure was partially resolved for each transition. The rotational transition frequencies were

Ziurys, Lucy M.

318

Instability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a  

E-Print Network [OSTI]

of viscous flow inside a closed circular cylinder rotating about its axis, periodically compressed by meansInstability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a J. F. Scott are known to support inertial oscillations whose frequencies are less than twice the basic rotation rate.1

Paris-Sud XI, Université de

319

Anisotropic Bianchi types VIII and IX locally rotationally symmetric cosmologies  

SciTech Connect (OSTI)

We present a class of exact cosmological solutions of Einstein-Maxwell equations, which are anisotropic and spatially homogeneous of Bianchi types VIII and IX, and class IIIb in the Stewart-Ellis classification of locally rotationally symmetric models. If we take the electromagnetic field equal to zero, a class of Bianchi types VIII/IX spatially homogeneous anisotropic cosmological solutions with perfect fluid is obtained.

Assad, M.J.D.; Soares, I.D.

1983-10-15T23:59:59.000Z

320

Hydrogen Bonds, Water Rotation and Proton Mobility Liaisons Hydrog`ene, Rotation de l'eau et Mobilit'e du  

E-Print Network [OSTI]

Hydrogen Bonds, Water Rotation and Proton Mobility Liaisons Hydrog`ene, Rotation de l'eau et H 3 O + est presque immo­ bilis'e par des liaisons hydrog`ene extrâ??emement fortes. Ces derni liaisons hydrog`ene de l'eau pure. Dans l'eau en dessous de 20 0 C, la rotation des mol'ecules est plus

Agmon, Noam

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

Large-scale anisotropy in stably stratified rotating flows  

SciTech Connect (OSTI)

We present results from direct numerical simulations of the Boussinesq equations in the presence of rotation and/or stratification, both in the vertical direction. The runs are forced isotropically and randomly at small scales and have spatial resolutions of up to $1024^3$ grid points and Reynolds numbers of $\\approx 1000$. We first show that solutions with negative energy flux and inverse cascades develop in rotating turbulence, whether or not stratification is present. However, the purely stratified case is characterized instead by an early-time, highly anisotropic transfer to large scales with almost zero net isotropic energy flux. This is consistent with previous studies that observed the development of vertically sheared horizontal winds, although only at substantially later times. However, and unlike previous works, when sufficient scale separation is allowed between the forcing scale and the domain size, the total energy displays a perpendicular (horizontal) spectrum with power law behavior compatible with $\\sim k_\\perp^{-5/3}$, including in the absence of rotation. In this latter purely stratified case, such a spectrum is the result of a direct cascade of the energy contained in the large-scale horizontal wind, as is evidenced by a strong positive flux of energy in the parallel direction at all scales including the largest resolved scales.

Marino, Dr. Raffaele [National Center for Atmospheric Research (NCAR); Mininni, Dr. Pablo D. [Universidad de Buenos Aires, Argentina; Rosenberg, Duane L [ORNL; Pouquet, Dr. Annick [National Center for Atmospheric Research (NCAR)

2014-01-01T23:59:59.000Z

322

Wind Circulation in Selected Rotating Magnetic Early-B Stars  

E-Print Network [OSTI]

The rotating magnetic B stars have oblique dipolar magnetic fields and often anomalous helium and metallic compositions. These stars develop co-rotating torus-shaped clouds by channelling winds from their magnetic poles to an anchored planar disk over the magnetic equator. The line absorptions from the cloud can be studied as the complex rotates and periodically occults the star. We describe an analysis of the clouds of four stars (HD184927, beta Cep, sigma Ori E, and HR6684). From line synthesis models, we find that the metallic compositions are spatially uniform over the stars' surfaces. Next, using the Hubeny CIRCUS code, we demonstate that periodic UV continuum fluxes can be explained by the absorption of low-excitation lines. The analysis also quantifies the cloud temperatures, densities, and turbulences, which appear to increase inward toward the stars. The temperatures range from about 12,000K for the weak Fe lines up to temperatures of 33,000K for N V absorptions, which is in excess of temperatures expected from radiative equilibrium. The spectroscopic hallmark of this stellar class is the presence of strong C IV and N V resonance line absorptions at occultation phases and of redshifted emissions at magnetic pole-on phases. The emissions have characteristics which seem most compatible with the generation of high-energy shocks at the wind-cloud interface, as predicted by Babel.

Myron A. Smith; Detlef Groote

2001-04-03T23:59:59.000Z

323

Large rotating AdS black holes from fluid mechanics  

E-Print Network [OSTI]

We use the AdS/CFT correspondence to argue that large rotating black holes in global AdS(D) spaces are dual to stationary solutions of the relativistic Navier-Stokes equations on S**(D-2). Reading off the equation of state of this fluid from the thermodynamics of non-rotating black holes, we proceed to construct the nonlinear spinning solutions of fluid mechanics that are dual to rotating black holes. In all known examples, the thermodynamics and the local stress tensor of our solutions are in precise agreement with the thermodynamics and boundary stress tensor of the spinning black holes. Our fluid dynamical description applies to large non-extremal black holes as well as a class of large non-supersymmetric extremal black holes, but is never valid for supersymmetric black holes. Our results yield predictions for the thermodynamics of all large black holes in all theories of gravity on AdS spaces, for example, string theory on AdS(5) x S**5 and M theory on AdS(4) x S**7 and AdS(7) x S**4.

Sayantani Bhattacharyya; Subhaneil Lahiri; R. Loganayagam; Shiraz Minwalla

2008-07-25T23:59:59.000Z

324

Trailing edge noise theory for rotating blades in uniform flow  

E-Print Network [OSTI]

This paper presents a new formulation for trailing edge noise radiation from rotating blades based on an analytical solution of the convective wave equation. It accounts for distributed loading and the effect of mean flow and spanwise wavenumber. A commonly used theory due to Schlinker and Amiet (1981) predicts trailing edge noise radiation from rotating blades. However, different versions of the theory exist; it is not known which version is the correct one and what the range of validity of the theory is. This paper addresses both questions by deriving Schlinker and Amiet's theory in a simple way and by comparing it to the new formulation, using model blade elements representative of a wind turbine, a cooling fan and an aircraft propeller. The correct form of Schlinker and Amiet's theory (1981) is identified. It is valid at high enough frequency, i.e. for a Helmholtz number relative to chord greater than one and a rotational frequency much smaller than the angular frequency of the noise sources.

Sinayoko, Samuel; Agarwal, Anurag

2013-01-01T23:59:59.000Z

325

Magnetism and rotation in Herbig Ae/Be stars  

E-Print Network [OSTI]

Among the main sequence intermediate mass A and B stars, around 5% host large-scale organized magnetic fields. Most of these stars are very slow rotators compared to their non-magnetic counterparts, and show photospheric abundance anomalies. They are referred to as the Ap/Bp stars. One of the greatest challenges, today is to understand the origin of their magnetic field and their slow rotation. The favoured hypothesis is a fossil origin of the magnetic field, in which the magnetic fields of Ap/Bp stars are relics of those which existed in the parental molecular clouds during the formation. This implies that the magnetic field must survive all the initial phases of the stellar evolution and especially the pre-main sequence (PMS) phase. This is consistent with the general belief that magnetic braking occurs during the PMS phase, which sheds angular momentum and slows the rotation of these stars. In this context, we proceeded with a survey of a sample of around 50 PMS Herbig Ae/Be stars, using the new spectropol...

Alecian, E; Catala, C; Folsom, C; Grunhut, J; Donati, J -F; Petit, P; Bagnulo, S; Böhm, T; Bouret, J -C; Landstreet, J D

2007-01-01T23:59:59.000Z

326

Heat transport measurements in turbulent rotating Rayleigh-Benard convection  

SciTech Connect (OSTI)

We present experimental heat transport measurements of turbulent Rayleigh-Benard convection with rotation about a vertical axis. The fluid, water with Prandtl number ({sigma}) about 6, was confined in a cell which had a square cross section of 7.3 cm x 7.3 cm and a height of 9.4 cm. Heat transport was measured for Rayleigh numbers 2 x 10{sup 5} < Ra < 5 x 10{sup 8} and Taylor numbers 0 < Ta < 5 x 10{sup 9}. We show the variation of normalized heat transport, the Nusselt number, at fixed dimensional rotation rate {Omega}{sub D}, at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed Rossby number Ro. The scaling of heat transport in the range 10{sup 7} to about 10{sup 9} is roughly 0.29 with a Ro dependent coefficient or equivalently is also well fit by a combination of power laws of the form a Ra{sup 1/5} + b Ra{sup 1/3} . The range of Ra is not sufficient to differentiate single power law or combined power law scaling. The overall impact of rotation on heat transport in turbulent convection is assessed.

Ecke, Robert E [Los Alamos National Laboratory; Liu, Yuanming [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

327

Waves and instabilities in dissipative rotating superfluid neutron stars  

E-Print Network [OSTI]

We discuss wave propagation in rotating superfluid neutron star cores, taking into account the vortex mediated mutual friction force. For models where the two fluids co-rotate in the unperturbed state, our analysis clarifies the role of chemical coupling and entrainment for sound and inertial waves. We also investigate the mutual friction damping, providing results that demonstrate the well-known fact that sound waves propagating along a vortex array are undamped. We show that the same is not true for inertial waves, which are damped by the mutual friction regardless of the propagation direction. We then include the vortex tension, which arises due to local vortex curvature. Focussing on purely transverse inertial waves, we derive the small correction that the tension induces in the wave frequency. Finally, we allow for a relative linear flow in the background (along the rotation axis). In this case we show how the mutual friction coupling may induce a dynamical instability in the inertial waves. We discuss the critical flow required for the instability to be present, its physical interpretation and the possible relevance it may have for neutron star physics.

T. Sidery; N. Andersson; G. L. Comer

2007-06-05T23:59:59.000Z

328

SOLAR ROTATION RATE DURING THE CYCLE 24 MINIMUM IN ACTIVITY  

SciTech Connect (OSTI)

The minimum of solar cycle 24 is significantly different from most other minima in terms of its duration as well as its abnormally low levels of activity. Using available helioseismic data that cover epochs from the minimum of cycle 23 to now, we study the differences in the nature of the solar rotation between the minima of cycles 23 and 24. We find that there are significant differences between the rotation rates during the two minima. There are differences in the zonal-flow pattern too. We find that the band of fast rotating region close to the equator bifurcated around 2005 and recombined by 2008. This behavior is different from that during the cycle 23 minimum. By autocorrelating the zonal-flow pattern with a time shift, we find that in terms of solar dynamics, solar cycle 23 lasted for a period of 11.7 years, consistent with the result of Howe et al. (2009). The autocorrelation coefficient also confirms that the zonal-flow pattern penetrates through the convection zone.

Antia, H. M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Basu, Sarbani, E-mail: antia@tifr.res.i, E-mail: sarbani.basu@yale.ed [Department of Astronomy, Yale University, P.O. Box 208101, New Haven CT 06520-8101 (United States)

2010-09-01T23:59:59.000Z

329

Investigating the point seismic array concept with seismic rotation measurements.  

SciTech Connect (OSTI)

Spatially-distributed arrays of seismometers are often utilized to infer the speed and direction of incident seismic waves. Conventionally, individual seismometers of the array measure one or more orthogonal components of rectilinear particle motion (displacement, velocity, or acceleration). The present work demonstrates that measure of both the particle velocity vector and the particle rotation vector at a single point receiver yields sufficient information to discern the type (compressional or shear), speed, and direction of an incident plane seismic wave. Hence, the approach offers the intriguing possibility of dispensing with spatially-extended received arrays, with their many problematic deployment, maintenance, relocation, and post-acquisition data processing issues. This study outlines straightforward mathematical theory underlying the point seismic array concept, and implements a simple cross-correlation scanning algorithm for determining the azimuth of incident seismic waves from measured acceleration and rotation rate data. The algorithm is successfully applied to synthetic seismic data generated by an advanced finite-difference seismic wave propagation modeling algorithm. Application of the same azimuth scanning approach to data acquired at a site near Yucca Mountain, Nevada yields ambiguous, albeit encouraging, results. Practical issues associated with rotational seismometry are recognized as important, but are not addressed in this investigation.

Abbott, Robert E.; Aldridge, David Franklin

2009-02-01T23:59:59.000Z

330

Braking index of isolated uniformly rotating magnetized pulsars  

E-Print Network [OSTI]

Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate in detail, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of $\\Omega$. This relation leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The MDR model predicts $n$ exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of $n$, individually accurate to a few percent or better, in the range 1$ <$ n $ < $ 2.8, which is consi...

Hamil, Oliver; Urbanec, Martin; Urbancova, Gabriela

2015-01-01T23:59:59.000Z

331

Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates  

E-Print Network [OSTI]

We consider a 2D rotating Bose gas described by the Gross-Pitaevskii (GP) theory and investigate the properties of the ground state of the theory for rotational speeds close to the critical speed for vortex nucleation. While one could expect that the vortex distribution should be homogeneous within the condensate we prove by means of an asymptotic analysis in the strongly interacting (Thomas-Fermi) regime that it is not. More precisely we rigorously derive a formula due to Sheehy and Radzihovsky [Phys. Rev. A 70, 063620(R) (2004)] for the vortex distribution, a consequence of which is that the vortex distribution is strongly inhomogeneous close to the critical speed and gradually homogeneizes when the rotation speed is increased. From the mathematical point of view, a novelty of our approach is that we do not use any compactness argument in the proof, but instead provide explicit estimates on the difference between the vorticity measure of the GP ground state and the minimizer of a certain renormalized energy...

Correggi, Michele

2012-01-01T23:59:59.000Z

332

A nonlinear calculation of rotating cavitation in inducers  

SciTech Connect (OSTI)

In the previous linear analysis (Tsujimoto et al., 1993) it was found that there can be a backward rotating cavitation as well as a forward mode which rotates faster than impeller. Although some shaft vibration has been observed which might be caused by the backward mode, experimental evidence has been obtained only for the forward mode. The ultimate goal of the present study is to answer the question which mode of the cavitation instabilities -- cavitation surge and the two modes of rotating cavitation -- occurs in a given system and operating condition, and to find out analytical method to determine their amplitude. A time marching non-linear 2-D flow analysis was carried out for this purpose. It was found that the increase of cavitation compliance at lower inlet pressure can be a factor which limits the amplitude. The mode selectivity is mainly dependent on the stability limit obtained by a linear analysis for which the phase delay of cavity has a most important effect.

Tsujimoto, Y.; Watanabe, S.; Yoshida, Y. [Osaka Univ., Osaka (Japan); Kamijo, K. [Kakuda Research Center (Japan). Rocket Propulsion Division

1994-12-31T23:59:59.000Z

333

Emergence of rotational bands in ab initio no-core configuration interaction calculations  

E-Print Network [OSTI]

Rotational bands have been observed to emerge in ab initio no-core configuration interaction (NCCI) calculations for p-shell nuclei, as evidenced by rotational patterns for excitation energies, electromagnetic moments, and electromagnetic transitions. We investigate the ab initio emergence of nuclear rotation in the Be isotopes, focusing on 9Be for illustration, and make use of basis extrapolation methods to obtain ab initio predictions of rotational band parameters for comparison with experiment. We find robust signatures for rotational motion, which reproduce both qualitative and quantitative features of the experimentally observed bands.

M. A. Caprio; P. Maris; J. P. Vary; R. Smith

2015-02-04T23:59:59.000Z

334

The Dosimetric Impact of Prostate Rotations During Electromagnetically Guided External-Beam Radiation Therapy  

SciTech Connect (OSTI)

Purpose: To study the impact of daily rotations and translations of the prostate on dosimetric coverage during radiation therapy (RT). Methods and Materials: Real-time tracking data for 26 patients were obtained during RT. Intensity modulated radiation therapy plans meeting RTOG 0126 dosimetric criteria were created with 0-, 2-, 3-, and 5-mm planning target volume (PTV) margins. Daily translations and rotations were used to reconstruct prostate delivered dose from the planned dose. D{sub 95} and V{sub 79} were computed from the delivered dose to evaluate target coverage and the adequacy of PTV margins. Prostate equivalent rotation is a new metric introduced in this study to quantify prostate rotations by accounting for prostate shape and length of rotational lever arm. Results: Large variations in prostate delivered dose were seen among patients. Adequate target coverage was met in 39%, 65%, and 84% of the patients for plans with 2-, 3-, and 5-mm PTV margins, respectively. Although no correlations between prostate delivered dose and daily rotations were seen, the data showed a clear correlation with prostate equivalent rotation. Conclusions: Prostate rotations during RT could cause significant underdosing even if daily translations were managed. These rotations should be managed with rotational tolerances based on prostate equivalent rotations.

Amro, Hanan, E-mail: hanan.amro@gmail.com [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Hamstra, Daniel A.; Mcshan, Daniel L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Sandler, Howard [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States)] [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States); Vineberg, Karen; Hadley, Scott; Litzenberg, Dale [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

2013-01-01T23:59:59.000Z

335

Solar surface rotation: N-S asymmetry and recent speed-up  

E-Print Network [OSTI]

Context. The relation between solar surface rotation and sunspot activity still remains open. Sunspot activity has dramatically reduced in solar cycle 24 and several solar activity indices and flux measurements experienced unprecedentedly low levels during the last solar minimum. Aims. We aim to reveal the momentary variation of solar surface rotation, especially during the recent years of reducing solar activity. Methods. We used a dynamic, differentially rotating reference system to determine the best-fit annual values of the differential rotation parameters of active longitudes of solar X-ray flares and sunspots in 1977-2012. Results. The evolution of rotation of solar active longitudes obtained with X-ray flares and with sunspots is very similar. Both hemispheres speed up since the late 1990s, with the southern hemisphere rotating slightly faster than the north. Earlier, in 1980s, rotation in the northern hemisphere was considerably faster, but experienced a major decrease in the early 1990s. On the other...

Zhang, L; Usoskin, I

2015-01-01T23:59:59.000Z

336

Rotational bands with identical transition energies in actinide nuclei  

SciTech Connect (OSTI)

We point out the existence of ground-state rotational bands with identical transition energies (up to spin 8{h bar}) in {sup 240}Pu, {sup 244}Cm, {sup 246}Cm, and {sup 250}Cf. The corresponding transitions in the ground-state bands of {sup 236}U and {sup 238}U have identical energies (within {similar to}2 keV) up to spin 24{h bar}. These features are very similar to those recently observed for superdeformed bands in the mass-150 and mass-190 regions and suggest that the phenomenon of identical bands is not restricted to superdeformed bands.

Ahmad, I.; Carpenter, M.P.; Chasman, R.R.; Janssens, R.V.F.; Khoo, T.L. (Argonne National Laboratory, Argonne, Illinois (USA))

1991-09-01T23:59:59.000Z

337

Quantum-information approach to rotating Bose-Einstein condensates  

SciTech Connect (OSTI)

We investigate the two-dimensional weakly interacting rotating Bose-Einstein condensate by the tools of quantum information theory. The critical exponents of the ground-state fidelity susceptibility and the correlation length of the system are obtained for the sudden change of the ground state when the first vortex is formed. This sudden change can also be indicated by the ground state entanglement. We also find the single-particle entanglement can be an indicator of the angular momentums for some real ground states. The single-particle entanglement of fractional quantum Hall states such as Laughlin state and Pfaffian state is also studied.

Liu Zhao; Guo Hongli; Chen Shu; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2009-12-15T23:59:59.000Z

338

Control coil arrangement for a rotating machine rotor  

DOE Patents [OSTI]

A rotating machine (e.g., a turbine, motor or generator) is provided wherein a fixed solenoid or other coil configuration is disposed adjacent to one or both ends of the active portion of the machine rotor for producing an axially directed flux in the active portion so as to provide planar axial control at single or multiple locations for rotor balance, levitation, centering, torque and thrust action. Permanent magnets can be used to produce an axial bias magnetic field. The rotor can include magnetic disks disposed in opposed, facing relation to the coil configuration.

Shah, Manoj R. (Latham, NY); Lewandowsk, Chad R. (Amsterdam, NY)

2001-07-31T23:59:59.000Z

339

Gamma N Delta Form Factors and Wigner Rotations  

E-Print Network [OSTI]

For more than 50 years the Delta N gamma form factors have been studied experimentally, theoretically, and phenomenologically. Although there has been substantial progress in understanding their behavior, there remains much work to be done. A major tool used in many investigations is the Jones-Scadron Delta rest frame parametrization of the three Delta N gamma form factors. We point out that many studies utilizing this parametrization may not account for Wigner rotations and the consequent helicity mixing that ensues when the Delta is not at rest.

Milton Dean Slaughter

2008-10-28T23:59:59.000Z

340

Transitions in two sinusoidally coupled Josephson junction rotators  

SciTech Connect (OSTI)

We investigate the dynamics of two sinusoidally coupled Josephson junction rotators to provide a clear knowledge of the behaviors in different regions of the parameter space. The dynamical states are identified, and the transitions among these states are studied. The properties of the current-voltage curves are investigated. Further more, we observed the chaotic states in some regions of parameter space. We conjecture it may caused by the competition of two periodic potentials: one is the external field, another is the interacting of two particles.

Qian Min [School of Mathematical Sciences, Peking University, Beijing 100871 (China); Wang Jiazeng [Department of Mathematics, Shanghai University, Shanghai 200444 (China)], E-mail: wangjiazen@yahoo.com.cn

2008-08-15T23:59:59.000Z

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341

Rotation, Statistical Dynamics and Kinematics of Globular Clusters  

E-Print Network [OSTI]

Evolution with mass segregation and the evolution of the rotation of cores are both discussed for self-similar core collapse. Evolution with angular velocity proportional to the square root of the density is predicted. On the Dynamical Main Sequence of globular clusters the energy emission from binaries balances the energy expended in expanding the halo. Newton's exactly solved N-body problem is then given, along with recent generalisations, all of which have no violent relaxation, but a new type of statistical equilibrium is discussed. Finally, we set the creation of streams in the Galaxy's halo in the historical context of their discovery.

Donald Lynden-Bell

2000-07-10T23:59:59.000Z

342

Plasma Frequency Shift Due to a Slowly Rotating Compact Star  

E-Print Network [OSTI]

We investigate the effects of a slowly rotating compact gravitational source on electron oscillations in a homogeneous electrically neutral plasma in the absence of an external electric or magnetic field. Neglecting the random thermal motion of the electrons we assume the gravitoelectromagnetic approximation to the general theory of relativity for the gravitational field. It is shown that there is a shift in the plasma frequency and hence in the dielectric constant of the plasma due to the gravitomagnetic force. We also give estimates for the difference in the frequency of radially transmitted electromagnetic signals for typical compact star candidates.

Babur M. Mirza; Hamid Saleem

2005-05-10T23:59:59.000Z

343

Extremal charged rotating dilaton black holes in odd dimensions  

SciTech Connect (OSTI)

Employing higher-order perturbation theory, we find a new class of charged rotating black hole solutions of Einstein-Maxwell-dilaton theory with general dilaton coupling constant. Starting from the Myers-Perry solutions, we use the electric charge as the perturbative parameter, and focus on extremal black holes with equal-magnitude angular momenta in odd dimensions. We perform the perturbations up to 4th order for black holes in 5 dimensions and up to 3rd order in higher odd dimensions. We calculate the physical properties of these black holes and study their dependence on the charge and the dilaton coupling constant.

Allahverdizadeh, Masoud; Kunz, Jutta; Navarro-Lerida, Francisco [Institut fuer Physik, Universitaet Oldenburg, Postfach 2503 D-26111 Oldenburg (Germany); Departamento de Fisica Atomica, Molecular y Nuclear, Ciencias Fisicas Universidad Complutense de Madrid, E-28040 Madrid (Spain)

2010-09-15T23:59:59.000Z

344

Extremal Charged Rotating Dilaton Black Holes in Odd Dimensions  

E-Print Network [OSTI]

Employing higher order perturbation theory, we find a new class of charged rotating black hole solutions of Einstein-Maxwell-dilaton theory with general dilaton coupling constant. Starting from the Myers-Perry solutions, we use the electric charge as the perturbative parameter, and focus on extremal black holes with equal-magnitude angular momenta in odd dimensions. We perform the perturbations up to 4th order for black holes in 5 dimensions and up to 3rd order in higher odd dimensions. We calculate the physical properties of these black holes and study their dependence on the charge and the dilaton coupling constant.

Masoud Allahverdizadeh; Jutta Kunz; Francisco Navarro-Lerida

2010-07-24T23:59:59.000Z

345

THE ROTATION PROFILE OF SOLAR MAGNETIC FIELDS BETWEEN {+-}60 Degree-Sign LATITUDES  

SciTech Connect (OSTI)

Through a cross-correlation analysis of the Carrington synoptic maps of solar photospheric magnetic fields from Carrington Rotation Nos. 1625 to 2129 (from 1975 February to 2012 October), the sidereal rotation rates of solar magnetic fields between {+-}60 Degree-Sign latitudes are investigated. It seems that the temporal variation of rotation rates should be related to the solar cycle phase. The rotation profile of magnetic fields is obtained: the sidereal rotation rates decrease from the equator to mid-latitude and reach their minimum values of about 13.16 deg day{sup -1} (13.17 deg day{sup -1}) at 53 Degree-Sign (54 Degree-Sign ) latitude in the northern (southern) hemisphere, then increase toward higher latitudes. This rotation profile is different from the differential rotation law obtained by Snodgrass from a cross-correlation analysis of daily magnetograms, in which the rotation rates show a steep decrease from the equator to the poles. However, it is much closer to the quasi-rigid rotation law derived by Stenflo from an auto-correlation analysis of daily magnetograms. Some possible interpretations are discussed for the resulting rotation profile.

Shi, X. J.; Xie, J. L., E-mail: shixiangjun@ynao.ac.cn [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)

2013-08-10T23:59:59.000Z

346

Evolution of magnetized, differentially rotating neutron stars: Simulations in full general relativity  

E-Print Network [OSTI]

We study the effects of magnetic fields on the evolution of differentially rotating neutron stars, which can form in stellar core collapse or binary neutron star coalescence. Magnetic braking and the magnetorotational instability (MRI) both redistribute angular momentum; the outcome of the evolution depends on the star's mass and spin. Simulations are carried out in axisymmetry using our recently developed codes which integrate the coupled Einstein-Maxwell-MHD equations. For initial data, we consider three categories of differentially rotating, equilibrium configurations, which we label normal, hypermassive and ultraspinning. Hypermassive stars have rest masses exceeding the mass limit for uniform rotation. Ultraspinning stars are not hypermassive, but have angular momentum exceeding the maximum for uniform rotation at the same rest mass. We show that a normal star will evolve to a uniformly rotating equilibrium configuration. An ultraspinning star evolves to an equilibrium state consisting of a nearly uniformly rotating central core, surrounded by a differentially rotating torus with constant angular velocity along magnetic field lines, so that differential rotation ceases to wind the magnetic field. In addition, the final state is stable against the MRI, although it has differential rotation. For a hypermassive neutron star, the MHD-driven angular momentum transport leads to catastrophic collapse of the core. The resulting rotating black hole is surrounded by a hot, massive, magnetized torus undergoing quasistationary accretion, and a magnetic field collimated along the spin axis--a promising candidate for the central engine of a short gamma-ray burst. (Abridged)

Matthew D. Duez; Yuk Tung Liu; Stuart L. Shapiro; Masaru Shibata; Branson C. Stephens

2006-05-12T23:59:59.000Z

347

Bulk emission of scalars by a rotating black hole  

E-Print Network [OSTI]

We study in detail the scalar-field Hawking radiation emitted into the bulk by a higher-dimensional, rotating black hole. We numerically compute the angular eigenvalues, and solve the radial equation of motion in order to find transmission factors. The latter are found to be enhanced by the angular momentum of the black hole, and to exhibit the well-known effect of superradiance. The corresponding power spectra for scalar fields show an enhancement with the number of dimensions, as in the non-rotating case. We compute the total mass loss rate of the black hole for a variety of black-hole angular momenta and bulk dimensions, and find that, in all cases, the bulk emission remains significantly smaller than the brane emission. The angular-momentum loss rate is also computed and found to have a smaller value in the bulk than on the brane. We present accurate bulk-to-brane emission ratios for a range of scenarios.

M. Casals; S. R. Dolan; P. Kanti; E. Winstanley

2008-07-17T23:59:59.000Z

348

Measurement of Gravitomagnetic and Acceleration Fields Around Rotating Superconductors  

E-Print Network [OSTI]

It is well known that a rotating superconductor produces a magnetic field proportional to its angular velocity. The authors conjectured earlier, that in addition to this so-called London moment, also a large gravitomagnetic field should appear to explain an apparent mass increase of Niobium Cooper-pairs. A similar field is predicted from Einstein's general relativity theory and the presently observed amount of dark energy in the universe. An experimental facility was designed and built to measure small acceleration fields as well as gravitomagnetic fields in the vicinity of a fast rotating and accelerating superconductor in order to detect this so-called gravitomagnetic London moment. This paper summarizes the efforts and results that have been obtained so far. Measurements with Niobium superconductors indeed show first signs which appear to be within a factor of 2 of our theoretical prediction. Possible error sources as well as the experimental difficulties are reviewed and discussed. If the gravitomagnetic London moment indeed exists, acceleration fields could be produced in a laboratory environment.

M. Tajmar; F. Plesescu; B. Seifert; K. Marhold

2006-10-17T23:59:59.000Z

349

Geothermal heating enhances atmospheric asymmetries on synchronously rotating planets  

E-Print Network [OSTI]

Earth-like planets within the liquid water habitable zone of M type stars may evolve into synchronous rotators. On these planets, the sub-stellar hemisphere experiences perpetual daylight while the opposing anti-stellar hemisphere experiences perpetual darkness. Because the night-side hemisphere has no direct source of energy, the air over this side of the planet is prone to freeze out and deposit on the surface, which could result in atmospheric collapse. However, general circulation models (GCMs) have shown that atmospheric dynamics can counteract this problem and provide sufficient energy transport to the anti-stellar side. Here we use an idealized GCM to consider the impact of geothermal heating on the habitability of synchronously rotating planets. Geothermal heating may be expected due to tidal interactions with the host star, and the effects of geothermal heating provide additional habitable surface area and may help to induce melting of ice on the anti-stellar hemisphere. We also explore the persisten...

Haqq-Misra, Jacob

2014-01-01T23:59:59.000Z

350

Faraday Rotation Observations of Magnetic Fields in galaxy Clusters  

E-Print Network [OSTI]

The presence of magnetic fields in the intracluster medium in clusters of galaxies has been revealed through several different observational techniques. These fields may be dynamically important in clusters as they will provide additional pressure support to the intracluster medium as well as inhibit transport mechanisms such as thermal conduction. Here, we review the current observational state of Faraday rotation measure studies of the cluster fields. The fields are generally found to be a few to 10 microG in non-cooling core clusters and ordered on scales of 10-20 kpc. Studies of sources at large impact parameters show that the magnetic fields extend from cluster cores to radii of at least 500 kpc. In central regions of cooling core systems the field strengths are often somewhat higher (10-40 microG) and appear to be ordered on smaller scales of a few to 10 kpc. We also review some of the recent work on interpreting Faraday rotation measure observations through theory and numerical simulations. These techniques allow us to build up a much more detailed view of the strength and topology of the fields.

Tracy E. Clarke

2004-12-10T23:59:59.000Z

351

On the Nuclear Rotation Curve of M31  

E-Print Network [OSTI]

The nuclear rotation curve of M31, as observed by the Hubble Space Telescope Faint Object Camera Spectrograph, shows a significant disturbance coinciding with the off-center brightness peak, P1. This +/- 60 km/s feature is distinguished by a local velocity maximum centered on P1 and a local minimum approxmately 0.08" closer to P2. If the M31 double nucleus is an eccentric disk with an off-center density concentration, as suggested by Tremaine, then the self-gravity of the disk can produce just such a disturbance. The expected kinematic signature is calculated approximately by examining sequences of closed periodic orbits in a Kepler potential perturbed by a model disk potential that precesses at constant frequency. The perturbation forces a steep negative eccentricity gradient in the sequence of closed orbits through the densest part of the disk, which reverses the arrangement of periapsis and apoapsis with respect to the central mass. Stars making up the inner part of the density concentration are at apoapsis, while stars making up the outer part are at periapsis, producing a steep local velocity gradient. This result is independent of the details of the mass distribution. The projected rotation curve of the model is shown to closely resemble that of M31, giving strong support to the eccentric disk picture.

Thomas S. Statler

1999-05-08T23:59:59.000Z

352

Instabilities of (near) extremal rotating black holes in higher dimensions  

E-Print Network [OSTI]

Recently, Durkee and Reall have conjectured a criterion for linear instability of rotating, extremal, asymptotically Minkowskian black holes in $d\\ge 4$ dimensions, such as the Myers-Perry black holes. They considered a certain elliptic operator, $\\cal A$, acting on symmetric traceless tensors intrinsic to the horizon. Based in part on numerical evidence, they suggested that if the lowest eigenvalue, $\\lambda$, of this operator is less than the critical value $-1/4$ ( called "effective BF-bound"), then the black hole is linearly unstable. In this paper, we prove their conjecture. Our proof uses a combination of methods such as (i) the "canonical energy method" of Hollands-Wald, (ii) algebraically special properties of the near horizon geometries associated with the black hole, and (iii) the structure of the (linearized) constraint equations. Our method of proof is also applicable to rotating, extremal asymptotically Anti-deSitter black holes. In that case, our methods show that "all" such black holes are unstable. Although we explicitly discuss in this paper only extremal black holes, we argue that our methods can be generalized straightforwardly to obtain the same results for "near" extremal black holes.

Stefan Hollands; Akihiro Ishibashi

2014-08-04T23:59:59.000Z

353

Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking  

E-Print Network [OSTI]

We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can b...

Allen, A; Shu, F H

2003-01-01T23:59:59.000Z

354

Rotating fiber array molecular driver and molecular momentum transfer device constructed therewith  

DOE Patents [OSTI]

A rotating fiber array molecular driver is disclosed which includes a magnetically suspended and rotated central hub to which is attached a plurality of elongated fibers extending radially therefrom. The hub is rotated so as to straighten and axially extend the fibers and to provide the fibers with a tip speed which exceeds the average molecular velocity of fluid molecules entering between the fibers. Molecules colliding with the sides of the rotating fibers are accelerated to the tip speed of the fiber and given a momentum having a directional orientation within a relatively narrow distribution angle at a point radially outward of the hub, which is centered and peaks at the normal to the fiber sides in the direction of fiber rotation. The rotating fiber array may be used with other like fiber arrays or with other stationary structures to form molecular momentum transfer devices such as vacuum pumps, molecular separators, molecular coaters, or molecular reactors.

Milleron, Norman (1854 San Juan, Berkeley, CA 94707)

1983-01-01T23:59:59.000Z

355

Optical rotation in RbTiOAsO4 (point group mm2) W. Kaminsky*, I  

E-Print Network [OSTI]

Optical rotation in RbTiOAsO4 (point group mm2) W. Kaminsky*, I , P. A. ThomasII and A. M. Glazer, UK Received March 5, 2001; accepted September 13, 2001 Abstract. Measurement of optical rotation in RbTiOAsO4 (RTA) with the tilter method resulted in an optical rotation of r12 ¼ þ17ð3� /mm

Kaminsky, Werner

356

Femtosecond Raman induced polarization spectroscopy studies of coherent rotational dynamics in molecular fluids  

SciTech Connect (OSTI)

We develop a polarization-sensitive femtosecond pump probe technique, Raman induced polarization spectroscopy (RIPS), to study coherent rotation in molecular fluids. By observing the collisional dephasing of the coherently prepared rotational states, we are able to extract information concerning the effects of molecular interactions on the rotational motion. The technique is quite sensitive because of the zero background detection method, and is also versatile due to its nonresonant nature.

Morgen, M.M. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; [Lawrence Berkeley National Lab., CA (United States)

1997-05-01T23:59:59.000Z

357

Doppler maps and surface differential rotation of EI Eri from the MUSICOS 1998 observations  

E-Print Network [OSTI]

We present time-series Doppler images of the rapidly-rotating active binary star EI Eri from spectroscopic observations collected during the MUSICOS multi-site campaign in 1998, since the critical rotation period of 1.947 days makes it impossible to obtain time-resolved images from a single site. From the surface reconstructions a weak solar-type differential rotation, as well as a tiny poleward meridional flow are measured.

Zs. K?vári; A. Washuettl; B. H. Foing; K. Vida; J. Bartus; K. Oláh; the MUSICOS 98 team

2008-11-03T23:59:59.000Z

358

E-Print Network 3.0 - axisymmetric rotating plasmas Sample Search...  

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

a high- quasi-axisymmetric stellarator B275 Figure 1. Plasma... Figure 3. Rotational transform profile of configuration C82. Figure ... Source: Carlos III de Madrid, Universidad -...

359

Fuel ion rotation measurement and its implications on H-mode theories  

SciTech Connect (OSTI)

Poloidal and toroidal rotation of the fuel ions (He{sup 2+}) and the impurity ions (C{sup 6+} and B{sup 5+}) in H-mode helium plasmas have been investigated in the DIII-D tokamak by means of charge exchange recombination spectroscopy, resulting in the discovery that the fuel ion poloidal rotation is in the ion diamagnetic drift direction while the impurity ion rotation is in the electron diamagnetic drift direction. The radial electric field obtained from radial force balance analysis of the measured pressure gradients and rotation velocities is shown to be the same regardless of which ion species is used and therefore is a more fundamental parameter than the rotation flows in studying H-mode phenomena. It is shown that the three contributions to the radial electric field (diamagnetic, poloidal rotation, and toroidal rotation terms) are comparable and consequently the poloidal flow does not solely represent the E {times} B flow. In the high-shear edge region, the density scale length is comparable to the ion poloidal gyroradius, and thus neoclassical theory is not valid there. In view of this new discovery that the fuel and impurity ions rotate in opposite sense, L-H transition theories based on the poloidal rotation may require improvement.

Kim, J.; Burrell, K.H.; Gohil, P.; Groebner, R.J.; Hinton, F.L.; Kim, Y.B.; Seraydarian, R. [General Atomics, San Diego, CA (United States); Mandl, W. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany). Oberflaechenphysik; Wade, M.R. [Oak Ridge National Lab., TN (United States)

1993-10-01T23:59:59.000Z

360

arthroscopic double-row rotator: Topics by E-print Network  

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

rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when...

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

asphalt-rubber rotational viscosity: Topics by E-print Network  

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

at birth. A fraction of the gravitational binding energy of collapse is stored in the free energy of differential rotation. This energy source may be tapped by viscous...

362

Modeling Poplar Growth as a Short Rotation Woody Crop for Biofuels  

E-Print Network [OSTI]

a Short Rotation Woody Crop for Biofuels Q. J. Hart 1,? , O.for cellulosic derived biofuels. The ability to accuratelycrops for bioenergy and biofuels applications. In vitro

Hart, Quinn James

2014-01-01T23:59:59.000Z

363

Microsoft Word - APRIL 2009 PMCDP Module CHRIS ESS Tutorial_ROTATION...  

Broader source: Energy.gov (indexed) [DOE]

or her to institute innovative changes and sound business practices once back at DOE. ESS Tutorial, Project Management Career Development Program ROTATION WITH INDUSTRY REV:...

364

Null Result for the Violation of Equivalence Principle with Free-Fall Rotating Gyroscopes  

E-Print Network [OSTI]

The differential acceleration between a rotating mechanical gyroscope and a non-rotating one is directly measured by using a double free-fall interferometer, and no apparent differential acceleration has been observed at the relative level of 2x10{-6}. It means that the equivalence principle is still valid for rotating extended bodies, i.e., the spin-gravity interaction between the extended bodies has not been observed at this level. Also, to the limit of our experimental sensitivity, there is no observed asymmetrical effect or anti-gravity of the rotating gyroscopes as reported by hayasaka et al.

Luo, J; Zhang, Y Z; Zhou, Z B

2002-01-01T23:59:59.000Z

365

E-Print Network 3.0 - asteroid rotation periods Sample Search...  

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

5 > >> 1 National Aeronautics and Space Administration www.nasa.gov Summary: around the Sun in elliptical orbits, the asteroids also rotate, sometimes quite erratically,...

366

Transition to conservation tillage evaluated in San Joaquin Valley cotton and tomato rotations  

E-Print Network [OSTI]

62 , NUMBER 2 TABLE 3. Cotton plant stand establishment forcrops during one complete cotton- tomato rotation, FiveLM. 1996. Tillage. In: Cotton Production Manual. UC ANR Pub

2008-01-01T23:59:59.000Z

367

Low-Cost Alternative External Rotation Shoulder Brace and Review of Treatment in Acute Shoulder Dislocations  

E-Print Network [OSTI]

Amazon.com Corflex® Shoulder Abduction Pillow Sling Corflex® ER Shoulder Abduction Pillow with Sling Maxar® AS-300™shoulder in a position of abduction and external rotation.

Lacy, Kyle; Cooke, Chris; Cooke, Pat; Schupbach, Justin; Vaidya, Rahul

2015-01-01T23:59:59.000Z

368

Webinar: Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique  

Broader source: Energy.gov [DOE]

Video recording of the Fuel Cell Technologies Office webinar, Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique, originally presented on March 12, 2013.

369

Nanoparticles at liquid interfaces: Rotational dynamics and angular locking  

SciTech Connect (OSTI)

Nanoparticles with different surface morphologies that straddle the interface between two immiscible liquids are studied via molecular dynamics simulations. The methodology employed allows us to compute the interfacial free energy at different angular orientations of the nanoparticle. Due to their atomistic nature, the studied nanoparticles present both microscale and macroscale geometrical features and cannot be accurately modeled as a perfectly smooth body (e.g., spheres and cylinders). Under certain physical conditions, microscale features can produce free energy barriers that are much larger than the thermal energy of the surrounding media. The presence of these energy barriers can effectively “lock” the particle at specific angular orientations with respect to the liquid-liquid interface. This work provides new insights on the rotational dynamics of Brownian particles at liquid interfaces and suggests possible strategies to exploit the effects of microscale features with given geometric characteristics.

Razavi, Sepideh; Kretzschmar, Ilona [Department of Chemical Engineering, City College of City University of New York, New York, New York 10031 (United States)] [Department of Chemical Engineering, City College of City University of New York, New York, New York 10031 (United States); Koplik, Joel [Department of Physics and The Benjamin Levich Institute for Physico-chemical Hydrodynamics, City College of City University of New York, New York, New York 10031 (United States)] [Department of Physics and The Benjamin Levich Institute for Physico-chemical Hydrodynamics, City College of City University of New York, New York, New York 10031 (United States); Colosqui, Carlos E., E-mail: carlos.colosqui@stonybrook.edu [Department of Mechanical Engineering, Stony Brook University, Stony Brook, New York 11794 (United States)

2014-01-07T23:59:59.000Z

370

Testing the isotropy of space using rotating quartz oscillators  

E-Print Network [OSTI]

Violations of Lorentz invariance by matter and light can generate direction- and frame-dependent anisotropies in particles inertial masses and, hence, a measurable modulation of the oscillation frequency of rotating quartz crystal oscillators. This allows simple and low maintenance experiments that are ideally suited for long-term data taking. Using the Standard Model Extension (SME) as a parameterizing framework, we study the magnitude of this putative frequency modulation. A preliminary experiment with room-temperature SC-cut crystals yields a frequency resolution in the $10^{-15}$ range with $\\sim 120$ hours of data and a limit of $\\tilde c_Q=(-1.8 \\pm 2.2)\\times 10^{-14}$\\,GeV on the most weakly constrained neutron-sector $c-$coefficient of the SME. Future experiments with cryogenic oscillators promise additional improvements in accuracy, opening up the potential for improved tests of Lorentz symmetry in the neutron, proton, electron and photon sector.

Anthony Lo; Philipp Haslinger; Eli Mizrachi; Loic Anderegg; Holger Müller; Michael Hohensee; Maxim Goryachev; Michael E Tobar

2015-01-28T23:59:59.000Z

371

COMPRESSIBLE STREAMING INSTABILITIES IN ROTATING THERMAL VISCOUS OBJECTS  

SciTech Connect (OSTI)

We study electromagnetic streaming instabilities in thermal viscous regions of rotating astrophysical objects, such as protostellar and protoplanetary magnetized accretion disks, molecular clouds, their cores, and elephant trunks. The obtained results can also be applied to any regions of interstellar medium, where different equilibrium velocities between charged species can arise. We consider a weakly and highly ionized three-component plasma consisting of neutrals and magnetized electrons and ions. The vertical perturbations along the background magnetic field are investigated. The effect of perturbation of collisional frequencies due to density perturbations of species is taken into account. The growth rates of perturbations are found in a wide region of wave number spectrum for media, where the thermal pressure is larger than the magnetic pressure. It is shown that in cases of strong collisional coupling of neutrals with ions the contribution of the viscosity is negligible.

Nekrasov, A. K., E-mail: anatoli.nekrassov@t-online.d [Institute of Physics of the Earth, Russian Academy of Sciences, 123995 Moscow (Russian Federation)

2009-10-10T23:59:59.000Z

372

Novel Carbon Films for Next Generation Rotating Equipment Applications  

SciTech Connect (OSTI)

This report describes the results of research performed on a new generation of low friction, wear resistant carbon coatings for seals and bearings in high speed rotating equipment. The low friction coatings, Near Frictionless Carbon (NFC), a high hydrogen content diamondlike carbon, and Carbide Derived Carbon (CDC), a conversion coating produced on the surfaces of metal carbides by halogenation, can be applied together or separately to improve the performance of seals and bearings, with benefits to energy efficiency and environmental protection. Because hard carbide ceramics, such as silicon carbide, are widely used in the seals industry, this coating is particularly attractive as a low cost method to improve performance. The technology of CDC has been licensed to an Illinois company, Carbide Derivative Technologies, Inc. (CDTI) to implement the commercialization of this material.

Michael McNallan; Ali Erdemir; Yury Gogotsi

2006-02-20T23:59:59.000Z

373

Quantum metrology with rotating matter waves in different geometries  

SciTech Connect (OSTI)

A promising practical application of entanglement is metrology, where quantum states can be used to make measurements beyond the shot noise limit. Here we consider how metrology schemes could be realised using atomic Bose-Einstein condensates (BECs) trapped in different potentials. In particular, we show that if a trapped BEC is rotated at just the right frequency, it can undergo a quantum phase transition characterised by large-scale entanglement spreading across the system. This simple process of stirring can generate interesting quantum states such as macroscopic superpositions of all the atoms flowing in opposite directions around a ring-shaped potential. We consider different trapping potentials and show how this leads to different entangled states. In particular, we find that by reducing the dimensionality of the system to one or two dimensions, it is possible to generate entangled states that are remarkably robust to the loss of atoms and so are ideally suited to precision measurement schemes.

Dunningham, J. A.; Cooper, J. J.; Hallwood, D. W. [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Institute of Natural Sciences, Massey University, Private Bag 102904, Auckland (New Zealand)

2012-09-01T23:59:59.000Z

374

Magnetism, rotation and accretion in Herbig Ae-Be stars  

E-Print Network [OSTI]

Studies of stellar magnetism at the pre-main sequence phase can provide important new insights into the detailed physics of the late stages of star formation, and into the observed properties of main sequence stars. This is especially true at intermediate stellar masses, where magnetic fields are strong and globally organised, and therefore most amenable to direct study. This talk reviews recent high-precision ESPaDOnS observations of pre-main sequence Herbig Ae-Be stars, which are yielding qualitatively new information about intermediate-mass stars: the origin and evolution of their magnetic fields, the role of magnetic fields in generating their spectroscopic activity and in mediating accretion in their late formative stages, and the factors influencing their rotational angular momentum.

Alecian, E; Catala, C; Folsom, C; Grunhut, J; Donati, J -F; Petit, P; Bagnulo, S; Bouret, T J -C; Landstreet, J D

2007-01-01T23:59:59.000Z

375

Periodic relativity: deflection of light, acceleration, rotation curves  

E-Print Network [OSTI]

Vectorial analysis relating to derivation of deflection of light is presented. Curvilinear acceleration is distinguished from the Newtonian polar conic acceleration. The difference between the two is due to the curvature term. Lorentz invariant expression for acceleration is derived. A physical theory of rotation curves of galaxies based on second solution to Einstein's field equation is presented. Theory is applied to Milky Way, M31, NGC3198 and Solar system. Modified Kepler's third law yields correct orbital periods of stars in a galaxy. Deviation factor in the line element of the theory happens to be the ratio of the Newtonian gravitational acceleration to the measured acceleration of the star in the galaxy. Therefore this deviation factor can replace the MOND function.

Vikram H. Zaveri

2014-12-08T23:59:59.000Z

376

Rotating mousehole improves top drive/conventional drilling  

SciTech Connect (OSTI)

Top drive speed and efficiency are limited and have not reached full potential because of operation ``bottlenecks`` during makeup or breakout of triple pipe stands and bottomhole assembly (BHA) change out. Operators and contractors analyzed tools to overcome these limitations and found a potential solution from International Tool Co., a supplier of kelly spinners, in a tool that has improved make/break efficiency and rig floor safety. The Phantom Mouse rotating mousehole assembly was developed to improve drilling efficiency on top-drive-equipped rigs. This new device tightens connections so pipe stands can be set back in derricks. Using the system, crews can quickly and efficiently make up and set back DP stands while drilling ahead with top drives. It can also be used to break out and lay down excess DP from the derrick.

NONE

1995-08-01T23:59:59.000Z

377

Rotational and magnetic field instabilities in neutron stars  

SciTech Connect (OSTI)

In this short review we present recent results on the dynamics of neutron stars and their magnetic fields. We discuss the progress that has been made, during the last 5 years, in understanding the rotational instabilities with emphasis to the one due to the f-mode, the possibility of using gravitational wave detection in constraining the parameters of neutron stars and revealing the equation of state as well as the detectability of gravitational waves produced during the unstable phase of a neutron star’s life. In addition we discuss the dynamics of extremely strong magnetic fields observed in a class of neutron stars (magnetars). Magnetic fields of that strength are responsible for highly energetic phenomena (giant flares) and we demonstrate that the analysis of the emitted electromagnetic radiation can lead in constraining the parameters of neutron stars. Furthermore, we present our results from the study of such violent phenomena in association with the emission of gravitational radiation.

Kokkotas, Kostas D. [Theoretical Astrophysics, IAAT, Eberhard Karls University of Tübingen, Tübingen 72076 (Germany)

2014-01-14T23:59:59.000Z

378

Innovative Sensors for Pipeline Crawlers: Rotating Permanent Magnet Inspection  

SciTech Connect (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they may encounter. To facilitate inspection of these ''unpiggable'' pipelines, recent inspection development efforts have focused on a new generation of powered inspection platforms that are able to crawl slowly inside a pipeline and can maneuver past the physical barriers that limit internal inspection applicability, such as bore restrictions, low product flow rate, and low pressure. The first step in this research was to review existing inspection technologies for applicability and compatibility with crawler systems. Most existing inspection technologies, including magnetic flux leakage and ultrasonic methods, had significant implementation limitations including mass, physical size, inspection energy coupling requirements and technology maturity. The remote field technique was the most promising but power consumption was high and anomaly signals were low requiring sensitive detectors and electronics. After reviewing each inspection technology, it was decided to investigate the potential for a new inspection method. The new inspection method takes advantage of advances in permanent magnet strength, along with their wide availability and low cost. Called rotating permanent magnet inspection (RPMI), this patent pending technology employs pairs of permanent magnets rotating around the central axis of a cylinder to induce high current densities in the material under inspection. Anomalies and wall thickness variations are detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. This inspection method is an alternative to the common concentric coil remote field technique that induces low-frequency eddy currents in ferromagnetic pipes and tubes. Since this is a new inspection method, both theory and experiment were used to determine fundamental capabilities and limitations. Fundamental finite element modeling analysis and experimental investigations performed during this development have led to the derivation of a first order analytical equation for designing rotating magnetizers to induce current and positioning sensors to record signals from anomalies. Experimental results confirm the analytical equation and the finite element calculations provide a firm basis for the design of RPMI systems. Experimental results have shown that metal loss anomalies and wall thickness variations can be detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. The design exploits the phenomenon that circumferential currents are easily detectable at distances well away from the magnets. Current changes at anomalies were detectable with commercial low cost Hall Effect sensors. Commercial analog to digital converters can be used to measure the sensor output and data analysis can be performed in real time using PC computer systems. The technology was successfully demonstrated during two blind benchmark tests where numerous metal loss defects were detected. For this inspection technology, the detection threshold is a function of wall thickness and corrosion depth. For thinner materials, the detection threshold was experimentally shown to be comparable to magnetic flux leakage. For wall thicknesses greater than three tenths of an inch, the detection threshold increases with wall thickness. The potential for metal loss anomaly sizing was demonstrated in the second benchmarking study, again with accuracy comparable to existing magnetic flux leakage technologies. The rotating permanent magnet system has the potential for inspecting unpiggable pipelines since the magnetizer configurations can be sufficiently small with respect to the bore of the pipe to pass obstructions that limit the application of many i

J. Bruce Nestleroth; Richard J. Davis; Stephanie Flamberg

2006-09-30T23:59:59.000Z

379

Turbulent Transport in Tokamak Plasmas with Rotational Shear  

SciTech Connect (OSTI)

Nonlinear gyrokinetic simulations are conducted to investigate turbulent transport in tokamak plasmas with rotational shear. At sufficiently large flow shears, linear instabilities are suppressed, but transiently growing modes drive subcritical turbulence whose amplitude increases with flow shear. This leads to a local minimum in the heat flux, indicating an optimal ExB shear value for plasma confinement. Local maxima in the momentum fluxes are observed, implying the possibility of bifurcations in the ExB shear. The critical temperature gradient for the onset of turbulence increases with flow shear at low flow shears; at higher flow shears, the dependence of heat flux on temperature gradient becomes less stiff. The turbulent Prandtl number is found to be largely independent of temperature and flow gradients, with a value close to unity.

Barnes, M.; Highcock, E. G. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP (United Kingdom); Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Parra, F. I.; Schekochihin, A. A. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP (United Kingdom); Cowley, S. C.; Roach, C. M. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

2011-04-29T23:59:59.000Z

380

Single-ended counter-rotating radial turbine for space application  

DOE Patents [OSTI]

A single-ended turbine with counter-rotating blades operating with sodium as the working fluid. The single-ended, counter-rotating feature of the turbine results in zero torque application to a space platform. Thus, maneuvering of the platform is not adversely affected by the turbine. 4 figs.

Coomes, E.P.; Wilson, D.G.; Webb, B.J.; McCabe, S.J.

1987-05-13T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

The effect of diamagnetic flows on turbulent driven ion toroidal rotation  

SciTech Connect (OSTI)

Turbulent momentum redistribution determines the radial profile of rotation in a tokamak. The momentum transport driven by diamagnetic flow effects is an important piece of the radial momentum transport for sub-sonic rotation, which is often observed in experiments. In a non-rotating state, the diamagnetic flow and the E × B flow must cancel. The diamagnetic flow and the E × B flow have different effects on the turbulent momentum flux, and this difference in behavior induces intrinsic rotation. The momentum flux is evaluated using gyrokinetic equations that are corrected to higher order in the ratio of the poloidal Larmor radius to the minor radius, which requires evaluation of the diamagnetic corrections to Maxwellian equilibria. To study the momentum transport due to diamagnetic flow effects, three experimental observations of ion rotation are examined. First, a strong pressure gradient at the plasma edge is shown to result in a significant inward momentum transport due to the diamagnetic effect, which may explain the observed peaking of rotation in a high confinement mode. Second, the direction of momentum transport is shown to change as collisionality increases, which is qualitatively consistent with the observed reversal of intrinsic rotation by varying plasma density and current. Last, the dependence of the intrinsic momentum flux on the magnetic shear is found, and it may explain the observed rotation changes in the presence of lower hybrid current drive.

Lee, J. P. [Courant Institute of Mathematical Sciences, New York University, New York, New York 10003 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10003 (United States); Barnes, M. [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)] [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States); Parra, F. I. [Rudolf Peierls Centre for Theoretical Physics, Oxford University, Oxford OX1 3NP (United Kingdom)] [Rudolf Peierls Centre for Theoretical Physics, Oxford University, Oxford OX1 3NP (United Kingdom); Belli, E. A.; Candy, J. [General Atomics, San Diego, California 92121 (United States)] [General Atomics, San Diego, California 92121 (United States)

2014-05-15T23:59:59.000Z

382

AGU Monograph, Plate Boundary Zones, in press. Page 1 Crustal Block Rotations and Plate Coupling  

E-Print Network [OSTI]

AGU Monograph, Plate Boundary Zones, in press. Page 1 Crustal Block Rotations and Plate Coupling that considering both block rotations and fault locking significantly improves the fit to the data over models by locking on #12;AGU Monograph, Plate Boundary Zones, in press. Page 2 block-bounding faults and apply

McCaffrey, Robert

383

Rotation Angle for the Optimum Tracking of One-Axis Trackers  

SciTech Connect (OSTI)

An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.

Marion, W. F.; Dobos, A. P.

2013-07-01T23:59:59.000Z

384

EXPERIMENTAL INVESTIGATIONS ON THE DESIGN OF A DUCTED COUNTER-ROTATING AXIAL FLOW FANS SYSTEM  

E-Print Network [OSTI]

[] Number of blades FR [] Front rotor R [mm] Blade radius RR [] Rear rotor CRS [] Counter-rotating system W to a conventional rotor or to a rotor-stator stage. The study of the variation of the rotation rates ratio show of the axial distance be- tween rotors does not seem to change the overall per- formances. This system has thus

Boyer, Edmond

385

Parametric mechanism of the rotation energy pumping by a relativistic plasma  

E-Print Network [OSTI]

An investigation of the kinematics of a plasma stream rotating in the pulsar magnetosphere is presented. On the basis of an exact set of equations describing the behavior of the plasma stream, the increment of the instability is obtained, and the possible relevance of this approach for the understanding of the pulsar rotation energy pumping mechanism is discussed.

G. Z. Machabeli; Zaza Osmanov; Swadesh M. Mahajan

2006-09-14T23:59:59.000Z

386

The circumstellar environment of rotating Wolf-Rayet Stars and the implications for GRB afterglows  

E-Print Network [OSTI]

If Wolf-Rayet stars are the progenitors of Gamma-ray bursts (GRBs), they must rotate rapidly to produce the GRB. This rotation may effect their stellar-wind bubbles and possibly explain why so many GRB afterglows occur in a constant density medium.

J. J. Eldridge

2006-10-13T23:59:59.000Z

387

Generalized Quaternion and Rotation in 3-space E (3-alfa,beta)  

E-Print Network [OSTI]

The paper explains how a unit generalized quaternion is used to represent a rotation of a vector in 3-dimensional space. We review of some algebraic properties of generalized quaternions and operations between them and then show their relation with the rotation matrix.

Mehdi Jafari; Yusuf Yayli

2015-02-01T23:59:59.000Z

388

WAVE-DRIVEN ROTATION IN CENTRIFUGAL MIRRORS Abraham J. Fetterman and Nathaniel J. Fisch  

E-Print Network [OSTI]

by harnessing alpha particle energy. This is an exten- sion of the alpha channeling effect. The alpha particleWAVE-DRIVEN ROTATION IN CENTRIFUGAL MIRRORS Abraham J. Fetterman and Nathaniel J. Fisch Department frequency waves. A fixed azimuthal ripple is a simple and efficient wave that could produce rotation

389

LeBonheur Children's Hospital/Aesthetic Surgery Plastic Surgery Rotation  

E-Print Network [OSTI]

LeBonheur Children's Hospital/Aesthetic Surgery Plastic Surgery Rotation PGY-7 (2nd year Resident) By the end of the Plastic Surgery Rotation at LeBonheur Children's Hospital and Aesthetic Surgery, the PGY-7 with the following conditions needing plastic surgery including but not limited to: · Mammary ptosis. mammary

Cui, Yan

390

American Institute of Aeronautics and Astronautics An Experimental Investigation on the Effects of Turbine Rotation  

E-Print Network [OSTI]

of Turbine Rotation Directions on the Wake Interference of Wind Turbines Wei Yuan1 , Ahmet Ozbay2 , Wei Tian3 to investigate on the effects of the relative rotation directions of two tandwm wind turbines on the power production performance and flow characteristics in the wakes of two wind turbines in tandem. The experimental

Hu, Hui

391

Establishment phase greenhouse gas emissions in short rotation woody biomass plantations  

E-Print Network [OSTI]

to short-rotation woody biomass crops (SRWC) for bioenergy in the Northern U.S. Lake States. GHG debts-rotation woody bio- energy crops (SRWC), specifically hybrid-poplar (Populus spp.) and willow (Salix spp.), being in the Northern Lake States, USA Marin M. Palmer a, *, Jodi A. Forrester a , David E. Rothstein b , David J

Turner, Monica G.

392

Rotational energy analysis for rotatingvibrating linear molecules in classical trajectory simulation  

E-Print Network [OSTI]

Rotational energy analysis for rotating­vibrating linear molecules in classical trajectory-specific vibrational energy analysis reported previously, the present method allows a reliable separation of the total calculation,6 one wishes to carry out mode-specific energy analysis at the end of each trajectory run

Kim, Myung Soo

393

ccsd-00021948,version1-29Mar2006 Bose-Einstein condensates in fast rotation  

E-Print Network [OSTI]

ccsd-00021948,version1-29Mar2006 Bose-Einstein condensates in fast rotation S. Stock, B. Battelier of atomic Bose-Einstein condensates confined in quadratic or quartic potentials, and give an overview the physics of condensates containing a single vortex line. We then address the regime of fast rotation

Boyer, Edmond

394

ccsd00003161, Vortex patterns in a fast rotating Bose-Einstein condensate  

E-Print Network [OSTI]

. Furthermore we restrict our analysis to the case of a two-dimensional gas in the xy plane, assumingccsd­00003161, version 1 ­ 26 Oct 2004 Vortex patterns in a fast rotating Bose-Einstein condensate, France (Dated: October 26, 2004) For a fast rotating condensate in a harmonic trap, we investigate

395

Energy extremals and Nonlinear Stability in a Variational theory of Barotropic Fluid - Rotating Sphere System  

E-Print Network [OSTI]

A new variational principle - extremizing the fixed frame kinetic energy under constant relative enstrophy - for a coupled barotropic flow - rotating solid sphere system is introduced with the following consequences. In particular, angular momentum is transfered between the fluid and the solid sphere through a modelled torque mechanism. The fluid's angular momentum is therefore not fixed but only bounded by the relative enstrophy, as is required of any model that supports super-rotation. The main results are: At any rate of spin $\\Omega $ and relative enstrophy, the unique global energy maximizer for fixed relative enstrophy corresponds to solid-body super-rotation; the counter-rotating solid-body flow state is a constrained energy minimum provided the relative enstrophy is small enough, otherwise, it is a saddle point. For all energy below a threshold value which depends on the relative enstrophy and solid spin $\\Omega $, the constrained energy extremals consist of only minimizers and saddles in the form of counter-rotating states$.$ Only when the energy exceeds this threshold value can pro-rotating states arise as global maximizers. Unlike the standard barotropic vorticity model which conserves angular momentum of the fluid, the counter-rotating state is rigorously shown to be nonlinearly stable only when it is a local constrained minima. The global constrained maximizer corresponding to super-rotation is always nonlinearly stable.

Chjan C. Lim

2006-02-22T23:59:59.000Z

396

Observations of rotating jets of carbon monoxide in comet Hale-Bopp with the IRAM interferometer  

E-Print Network [OSTI]

Observations of rotating jets of carbon monoxide in comet Hale-Bopp with the IRAM interferometer the projection of the jet mean velocity on the line of sight. As the jet rotates with the nucleus, the velocity, an interesting feature is to be noted. We have computed the mean photometric centre from the peak intensity

Demoulin, Pascal

397

Effect on plasma rotation of lower hybrid (LH) waves in Alcator C-Mod  

SciTech Connect (OSTI)

The injection of LH waves for current drive into a tokamak changes the ion toroidal rotation. In Alcator C-Mod, the direction of the steady state rotation change due to LH waves depends on the plasma current and the density. The change in rotation can be estimated by balancing the external torque of lower hybrid waves with the turbulent radial transport of the momentum. For high plasma current, the turbulent pinch and diffusion of the injected counter-current momentum are sufficient to explain the rotation change. However, for low plasma current, the change in the the intrinsic momentum transport (residual stress) for a non-rotating state is required to explain the co-current rotation change. Accordingly, we investigate the intrinsic momentum transport for the non-rotating state when diamagnetic flow and ExB flow cancel each other. The change in the intrinsic momentum transport due to lower hybrid waves is significant when the plasma current is low, which may explain the rotation reversal for low plasma current. The effect of changed q (safety factor) profile by lower hybrid on the intrinsic momentum transport is estimated by gyrokinetics.

Lee, J. P.; Barnes, M.; Parker, R. R.; Rice, J. E.; Parra, F. I.; Bonoli, P. T.; Reinke, M. L. [Plasma Science and Fusion Center, MIT, Cambridge, MA (United States)

2014-02-12T23:59:59.000Z

398

Non-commutative Quantum Mechanics in Three Dimensions and Rotational Symmetry  

E-Print Network [OSTI]

We generalize the formulation of non-commutative quantum mechanics to three dimensional non-commutative space. Particular attention is paid to the identification of the quantum Hilbert space in which the physical states of the system are to be represented, the construction of the representation of the rotation group on this space, the deformation of the Leibnitz rule accompanying this representation and the implied necessity of deforming the co-product to restore the rotation symmetry automorphism. This also implies the breaking of rotational invariance on the level of the Schroedinger action and equation as well as the Hamiltonian, even for rotational invariant potentials. For rotational invariant potentials the symmetry breaking results purely from the deformation in the sense that the commutator of the Hamiltonian and angular momentum is proportional to the deformation.

Debabrata Sinha; Biswajit Chakraborty; Frederik G Scholtz

2011-08-12T23:59:59.000Z

399

Control of molecular rotation with a chiral train of ultrashort pulses  

E-Print Network [OSTI]

Trains of ultrashort laser pulses separated by the time of rotational revival (typically, tens of picoseconds) have been exploited for creating ensembles of aligned molecules. In this work we introduce a chiral pulse train - a sequence of linearly polarized pulses with the polarization direction rotating from pulse to pulse by a controllable angle. The chirality of such a train, expressed through the period and direction of its polarization rotation, is used as a new control parameter for achieving selectivity and directionality of laser-induced rotational excitation. The method employs chiral trains with a large number of pulses separated on the time scale much shorter than the rotational revival (a few hundred femtosecond), enabling the use of conventional pulse shapers.

S. Zhdanovich; A. A. Milner; C. Bloomquist; J. Floß; I. Sh. Averbukh; J. W. Hepburn; V. Milner

2011-08-18T23:59:59.000Z

400

A global forest canopy height map from the Moderate Resolution Imaging Spectroradiometer and the Geoscience  

E-Print Network [OSTI]

- radiometer and the Geoscience Laser Altimeter System, Geophys. Res. Lett., 37, L15401, doi:10.1029/2010GL, is sensitive throughout the range of biomass [Lefsky et al., 2005a, 2005b]. Each lidar waveform is a high spatial resolution record of the energy returned when a shortduration pulse of light is returned from

Lefsky, Michael

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


401

Global ice cloud observations: radiative properties and statistics from moderate-resolution imaging spectroradiometer measurements  

E-Print Network [OSTI]

Ice clouds occur quite frequently, yet so much about these clouds is unknown. In recent years, numerous investigations and field campaigns have been focused on the study of ice clouds, all with the ultimate goal of gaining a better understanding...

Meyer, Kerry Glynne

2009-05-15T23:59:59.000Z

402

Subpixel burn detection in Moderate Resolution Imaging Spectroradiometer 500-m data with ARTMAP neural networks  

E-Print Network [OSTI]

as surface albedo, evapotranspiration, surface roughness) and atmospheric composition (emission of trace in operational production including Global Fire Atlas from European Space Agency (ESA) Along Track Scanning

Myneni, Ranga B.

403

Identification of anthropogenic and natural dust sources using Moderate Resolution Imaging Spectroradiometer (MODIS)  

E-Print Network [OSTI]

of West Africa, which includes one of the most active natural dust sources and the highest population density on the continent, are processed. Sources are identified on the basis of the persistence in the western United States to expansion of livestock grazing in the early twentieth century. In West Africa

404

BONA FIDE, STRONG-VARIABLE GALACTIC LUMINOUS BLUE VARIABLE STARS ARE FAST ROTATORS: DETECTION OF A HIGH ROTATIONAL VELOCITY IN HR CARINAE  

SciTech Connect (OSTI)

We report optical observations of the luminous blue variable (LBV) HR Carinae which show that the star has reached a visual minimum phase in 2009. More importantly, we detected absorptions due to Si IV lambdalambda4088-4116. To match their observed line profiles from 2009 May, a high rotational velocity of v{sub rot} approx = 150 +- 20 km s{sup -1} is needed (assuming an inclination angle of 30 deg.), implying that HR Car rotates at approx =0.88 +- 0.2 of its critical velocity for breakup (v{sub crit}). Our results suggest that fast rotation is typical in all strong-variable, bona fide galactic LBVs, which present S-Dor-type variability. Strong-variable LBVs are located in a well-defined region of the HR diagram during visual minimum (the 'LBV minimum instability strip'). We suggest this region corresponds to where v{sub crit} is reached. To the left of this strip, a forbidden zone with v{sub rot}/v{sub crit}>1 is present, explaining why no LBVs are detected in this zone. Since dormant/ex LBVs like P Cygni and HD 168625 have low v{sub rot}, we propose that LBVs can be separated into two groups: fast-rotating, strong-variable stars showing S-Dor cycles (such as AG Car and HR Car) and slow-rotating stars with much less variability (such as P Cygni and HD 168625). We speculate that supernova (SN) progenitors which had S-Dor cycles before exploding (such as in SN 2001ig, SN 2003bg, and SN 2005gj) could have been fast rotators. We suggest that the potential difficulty of fast-rotating Galactic LBVs to lose angular momentum is additional evidence that such stars could explode during the LBV phase.

Groh, J. H. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Damineli, A.; Moises, A. P.; Teodoro, M. [Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Rua do Matao 1226, Cidade Universitaria, 05508-090, Sao Paulo, SP (Brazil); Hillier, D. J. [Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara Street, Pittsburgh, PA 15260 (United States); Barba, R. [Departamento de fisica, Universidad de La Serena, Benavente 980, La Serena (Chile); Fernandez-Lajus, E.; Gamen, R. C.; Solivella, G., E-mail: jgroh@mpifr-bonn.mpg.d [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, and Instituto de Astrofisica de La Plata (CCT La Plata-CONICET), Paseo del Bosque S/N, B1900FWA, La Plata (Argentina)

2009-11-01T23:59:59.000Z

405

Three-dimensional airfoil performance measurements on a rotating wing  

SciTech Connect (OSTI)

The objective of this comprehensive research program was to study the effects of horizontal-axis wind turbine (HAWT) blade rotation on aerodynamic behavior below, near, and beyond stall. This paper describes the flow angle sensor used to measure angle of attack (AOA) and how the sensor was calibrated, and it gives results of pressure integrations on the blade. Aerodynamic, load, flow-visualization, and inflow measurements were made on a 10-m, three-bladed, downwind HAWT. A video camera was mounted on the rotor to record video images of tufts attached to the low-pressure side of a constant-chord, zero-twist blade. Load measurements were made using strain gages mounted every 10% of the blade's span. Pressure taps were located at 32 chordwise positions and revealed pressure distributions comparable with wind tunnel data. Inflow was measured using a vertical-plane array of eight propvane and five triaxial (U-V-W) prop-type anemometers located 10 m upwind in the predominant wind direction. Results show evidence of stall hysteresis and unsteadiness at high AOA. Correlations with analytical predictions and wind tunnel tests show good agreement at low AOA and poor agreement at high AOA. 7 refs., 12 figs.

Butterfield, C.P.

1989-06-01T23:59:59.000Z

406

Buoyancy and Penrose Process Produce Jets from Rotating Black Holes  

E-Print Network [OSTI]

The exact mechanism by which astrophysical jets are formed is still unknown. It is believed that necessary elements are a rotating (Kerr) black hole and a magnetised accreting plasma. We model the accreting plasma as a collection of magnetic flux tubes/strings. If such a tube falls into a Kerr black hole, then the leading portion loses angular momentum and energy as the string brakes, and to compensate for this loss, momentum and energy is redistributed to the trailing portion of the tube.} {We found that buoyancy creates a pronounced helical magnetic field structure aligned with the spin axis. Along the field lines, the plasma is centrifugally accelerated close to the speed of light. This process leads to unlimited stretching of the flux tube since one part of the tube continues to fall into the black hole and simultaneously the other part of the string is pushed outward. Eventually, reconnection cuts the tube, the inner part is filled with new material and the outer part forms a collimated bubble-structured...

Semenov, V S; Heyn, M F

2014-01-01T23:59:59.000Z

407

Hydrodynamics of rapidly rotating superfluid neutron stars with mutual friction  

E-Print Network [OSTI]

We study time evolutions of superfluid neutron stars, focussing on the nature of the oscillation spectrum, the effect of mutual friction force on the oscillations and the hydrodynamical spin-up phase of pulsar glitches. We linearise the dynamical equations of a Newtonian two-fluid model for rapidly rotating backgrounds. In the axisymmetric equilibrium configurations, the two fluid components corotate and are in beta-equilibrium. We use analytical equations of state that generate stratified and non-stratified stellar models, which enable us to study the coupling between the dynamical degrees of freedom of the system. By means of time evolutions of the linearised dynamical equations, we determine the spectrum of axisymmetric and non-axisymmetric oscillation modes, accounting for the contribution of the gravitational potential perturbations, i.e. without adopting the Cowling approximation. We study the mutual friction damping of the superfluid oscillations and consider the effects of the non-dissipative part of the mutual friction force on the mode frequencies. We also provide technical details and relevant tests for the hydrodynamical model of pulsar glitches discussed by Sidery, Passamonti and Andersson (2010). In particular, we describe the method used to generate the initial data that mimic the pre-glitch state, and derive the equations that are used to extract the gravitational-wave signal.

A. Passamonti; N. Andersson

2010-04-26T23:59:59.000Z

408

The Rotating Dyonic Black Holes Of Kaluza-Klein Theory  

E-Print Network [OSTI]

The most general electrically and magnetically charged rotating black hole solutions of 5 dimensional \\KK\\ theory are given in an explicit form. Various classical quantities associated with the black holes are derived. In particular, one finds the very surprising result that the gyromagnetic and gyroelectric ratios can become {\\tenit arbitrarily large}. The thermodynamic quantities of the black holes are calculated and a Smarr-type formula is obtained leading to a generalized first law of black hole thermodynamics. The properties of the extreme solutions are investigated and it is shown how they naturally separate into two classes. The extreme solutions in one class are found to have two unusual properties: (i). Their event horizons have zero angular velocity and yet they have non-zero ADM angular momentum. (ii). In certain circumstances it is possible to add angular momentum to these extreme solutions without changing the mass or charges and yet still maintain an extreme solution. Regarding the extreme black holes as elementary particles, their stability is discussed and it is found that they are stable provided they have sufficient angular momentum.

Dean Rasheed

1995-05-06T23:59:59.000Z

409

SIMULATED FARADAY ROTATION MEASURES TOWARD HIGH GALACTIC LATITUDES  

SciTech Connect (OSTI)

We study the Faraday rotation measure (RM) due to the Galactic magnetic field (GMF) toward high Galactic latitudes. The RM arises from the global, regular component as well as from the turbulent, random component of the GMF. We model the former based on observations and the latter using the data of magnetohydrodynamic turbulence simulations. For a large number of different GMF models, we produce mock RM maps around the Galactic poles and calculate various statistical quantities with the RM maps. We find that the observed medians of RMs toward the north and south Galactic poles, {approx}0.0 {+-} 0.5 rad m{sup -2} and {approx} + 6.3 {+-} 0.5 rad m{sup -2}, are difficult to explain with any of our many alternate GMF models. The standard deviation of observed RMs, {approx}9 rad m{sup -2}, is clearly larger than that of simulated RMs. The second-order structure function of observed RMs is substantially larger than that of simulated RMs, especially at small angular scales. We discuss other possible contributions to RM toward high Galactic latitudes. Besides observational errors and the intrinsic RM of background radio sources against which RM is observed, we suggest that the RM due to the intergalactic magnetic field may account for a substantial fraction of the observed RM. Finally, we note that reproducing the observed medians may require additional components or/and structures of the GMF that are not present in our models.

Akahori, Takuya; Kim, Jongsoo [Korea Astronomy and Space Science Institute, Daedeokdaero 776, Yuseong-Gu, Daejeon 305-348 (Korea, Republic of); Ryu, Dongsu [Department of Astronomy and Space Science, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Gaensler, B. M., E-mail: jskim@kasi.re.kr, E-mail: akahori@physics.usyd.edu.au, E-mail: bryan.gaensler@sydney.edu.au, E-mail: ryu@canopus.cnu.ac.kr [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia)

2013-04-20T23:59:59.000Z

410

Neutron Emission Spectroscopy of Fuel Ion Rotation and Fusion Power Components Demonstrated in the Trace Tritium Experiments at JET  

E-Print Network [OSTI]

Neutron Emission Spectroscopy of Fuel Ion Rotation and Fusion Power Components Demonstrated in the Trace Tritium Experiments at JET

411

Analysis of Rotating Collectors from the Private Region of JET with Carbon Wall and Metallic ITER-Like Wall  

E-Print Network [OSTI]

Analysis of Rotating Collectors from the Private Region of JET with Carbon Wall and Metallic ITER-Like Wall

412

Project of Rotating Carbon High-Power Neutron Target. Research of Graphite Properties for Production of High Intensity Neutron Source  

E-Print Network [OSTI]

Project of Rotating Carbon High-Power Neutron Target. Research of Graphite Properties for Production of High Intensity Neutron Source

Gubin, K V; Bak, P A; Kot, N K; Logatchev, P V

2001-01-01T23:59:59.000Z

413

Temperature dependence of thermal conductivities of coupled rotator lattice and the momentum diffusion in standard map  

E-Print Network [OSTI]

In contrary to other 1D momentum-conserving lattices such as the Fermi-Pasta-Ulam $\\beta$ (FPU-$\\beta$) lattice, the 1D coupled rotator lattice is a notable exception which conserves total momentum while exhibits normal heat conduction behavior. The temperature behavior of the thermal conductivities of 1D coupled rotator lattice had been studied in previous works trying to reveal the underlying physical mechanism for normal heat conduction. However, two different temperature behaviors of thermal conductivities have been claimed for the same coupled rotator lattice. These different temperature behaviors also intrigue the debate whether there is a phase transition of thermal conductivities as the function of temperature. In this work, we will revisit the temperature dependent thermal conductivities for the 1D coupled rotator lattice. We find that the temperature dependence follows a power law behavior which is different with the previously found temperature behaviors. Our results also support the claim that there is no phase transition for 1D coupled rotator lattice. We also give some discussion about the similarity of diffusion behaviors between the 1D coupled rotator lattice and the single kicked rotator also called the Chirikov standard map.

Yunyun Li; Nianbei Li; Baowen Li

2015-01-29T23:59:59.000Z

414

Simulation of Non-resonant Internal Kink Mode with Toroidal Rotation in NSTX  

SciTech Connect (OSTI)

Plasmas in spherical and conventional tokamaks, with weakly reversed shear q pro le and minimum q above but close to unity, are susceptible to an non-resonant (m, n ) = (1, 1) internal kink mode. This mode can saturate and persist and can induce a (2; 1) seed island for Neoclassical Tearing Mode (NTMs)1 . The mode can also lead to large energetic particle transport and signi cant broadening of beam-driven current. Motivated by these important e ects, we have carried out extensive nonlinear simulations of the mode with nite toroidal rotation using parameters and pro les of an NTSX plasma with a weakly reversed shear pro le. The numerical results show that, at the experimental level, plasma rotation has little e ect on either equilibrium or linear stability. However, rotation can signi cantly inuence the nonlinear dynamics of the (1, 1) mode and the the induced (2, 1) magnetic island. The simulation results show that a rotating helical equilibrium is formed and maintained in the nonlinear phase at nite plasma rotation. In contrast, for non-rotating cases, the nonlinear evolution exhibits dynamic oscillations between a quasi-2D state and a helical state. Furthermore, the e ects of rotation are found to greatly suppress the (2, 1) magnetic island even at a low level.

Fu, Guoyong

2013-07-16T23:59:59.000Z

415

Measuring the rotation period distribution of field M-dwarfs with Kepler  

E-Print Network [OSTI]

We have analysed 10 months of public data from the Kepler space mission to measure rotation periods of main-sequence stars with masses between 0.3 and 0.55 M_sun. To derive the rotational period we introduce the autocorrelation function and show that it is robust against phase and amplitude modulation and residual instrumental systematics. Of the 2483 stars examined, we detected rotation periods in 1570 (63.2%), representing an increase of a factor ~ 30 in the number of rotation period determination for field M-dwarfs. The periods range from 0.37-69.7 days, with amplitudes ranging from 1.0-140.8 mmags. The rotation period distribution is clearly bimodal, with peaks at ~ 19 and ~ 33 days, hinting at two distinct waves of star formation, a hypothesis that is supported by the fact that slower rotators tend to have larger proper motions. The two peaks of the rotation period distribution form two distinct sequences in period-temperature space, with the period decreasing with increasing temperature, reminiscent of ...

McQuillan, Amy; Mazeh, Tsevi

2013-01-01T23:59:59.000Z

416

The role of short-rotation woody crops in sustainable development  

SciTech Connect (OSTI)

One answer to increase wood production is by increasing management intensity on existing timberland, especially in plantation forests. Another is to convert land currently in agriculture to timberland. Short-rotation woody crops can be used in both cases. But, what are the environmental consequences? Short-rotation woody crops can provide a net improvement in environmental quality at both local and global scales. Conversion of agricultural land to short-rotation woody crops can provide the most environmental quality enhancement by reducing erosion, improving soil quality, decreasing runoff, improving groundwater quality, and providing better wildlife habitat. Forest products companies can use increased production from intensively managed short-rotation woody crop systems to offset decreased yield from the portion of their timberland that is managed less intensively, e.g. streamside management zones and other ecologically sensitive or unique areas. At the global scale, use of short-rotation woody crops for bioenergy is part of the solution to reduce greenhouse gases produced by burning fossil fuels. Incorporating short-rotation woody crops into the agricultural landscape also increases storage of carbon in the soil, thus reducing atmospheric concentrations. In addition, use of wood instead of alternatives such as steel, concrete, and plastics generally consumes less energy and produces less greenhouse gases. Cooperative research can be used to achieve energy, fiber, and environmental goals. This paper will highlight several examples of ongoing cooperative research projects that seek to enhance the environmental aspects of short-rotation woody crop systems. Government, industry, and academia are conducting research to study soil quality, use of mill residuals, nutrients in runoff and groundwater, and wildlife use of short-rotation woody crop systems in order to assure the role of short-rotation crops as a sustainable way of meeting society`s needs.

Shepard, J.P. [National Council of the Paper Industry for Air and Stream Improvement, Medford, MA (United States); Tolbert, V.R. [Oak Ridge National Lab., TN (United States)

1996-12-31T23:59:59.000Z

417

Modelling the effect of toroidal plasma rotation on magnetohydrodynamic instabilities in MAST  

SciTech Connect (OSTI)

Present day tokamaks are capable of generating toroidal flows approaching the ion sound speed. Such toroidal rotation is known to have a stabilising effect on resistive wall modes. Here the effects of plasma rotation and diamagnetic drifts on the n = 1 internal kink mode and high-n ballooning modes are presented with specific comparison to experimental data from MAST, Results from MAST concerning the effect of toroidal rotation driven by neutral beam injection (NBI) on sawteeth are presented. The sawteeth period is shown to increase as the co-NBI power, and thus the toroidal plasma rotation, is increased. Conversely, as the counter-NBI is increased, the sawtooth period decreases to some minimum that is shorter than in Ohmically heated plasmas, before lengthening at high toroidal flows. Magnetohydrodynamic stability analyses of the n = 1 internal kink mode with respect to toroidal rotation at finite ion diamagnetic frequency have been performed using a new code, called MISHKA-F. The results indicate that the marginally stable radial location of the q = 1 surface reaches a minimum at approximately the same counter-toroidal rotation as that which minimises the sawtooth period experimentally. It has also been shown that sheared toroidal rotation is able to stabilise the peeling-ballooning modes which are thought to be the likely trigger of Edge Localised Modes (ELMs). A model for ELM triggering in MAST is proposed, such that, initially the rotation shear keeps the edge stabilised until the pressure gradient sufficiently exceeds the stability boundary for static plasmas. When the mode becomes unstable, it grows, ties the flux surfaces together and consequently flattens the rotation profile. This further destabilises the plasma edge, leading to the ELM crash.

Chapman, I. T.; SArelma, S.; Hender, T. C.; Sharapov, S. E.; Meyer, H.; Kirk, A. [UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Huysmans, G. T. A. [Association EURATOM-CEA Cadarache, 13108 St. Paul-Lez-Durance (France); Mikhailovskii, A. B. [RRC Kurchatov Institute, Kurchatov Sqr 1, Moscow 123182 (Russian Federation); Wilson, H. R. [University of York, Heslington, York YO10 5DD (United Kingdom)

2006-11-30T23:59:59.000Z

418

Dynamic modeling of the reactive twin-screw co-rotating extrusion process: experimental validation by using inlet  

E-Print Network [OSTI]

and modification.1 The co-rotating twin-screw extruder is of particular interest due to its modular geometry or removing chemical species.3,4 Furthermore, the co-rotating twin-screw extruder can handle high viscosityDynamic modeling of the reactive twin-screw co-rotating extrusion process: experimental validation

Paris-Sud XI, Université de

419

Rotational fluxons of Bose-Einstein condensates in coplanar double-ring traps  

SciTech Connect (OSTI)

Rotational analogs to magnetic fluxons in conventional Josephson junctions are predicted to emerge in the ground state of rotating tunnel-coupled annular Bose-Einstein condensates (BECs). Such topological condensate-phase structures can be manipulated by external potentials. We determine conditions for observing macroscopic quantum tunneling of a fluxon. Rotational fluxons in double-ring BECs can be created, manipulated, and controlled by external potentials in different ways than is possible in the solid-state system, thus rendering them a promising candidate system for studying and utilizing quantum properties of collective many-particle degrees of freedom.

Brand, J. [Centre for Theoretical Chemistry and Physics, Massey University (Albany Campus), Private Bag 102 904, North Shore MSC, Auckland 0745 (New Zealand); Institute of Natural Sciences, Massey University (Albany Campus), Private Bag 102 904, North Shore MSC, Auckland 0745 (New Zealand); Haigh, T. J. [Institute of Fundamental Sciences, Massey University (Manawatu Campus), Private Bag 11 222, Palmerston North 4442 (New Zealand); Zuelicke, U. [Institute of Fundamental Sciences, Massey University (Manawatu Campus), Private Bag 11 222, Palmerston North 4442 (New Zealand); Centre for Theoretical Chemistry and Physics, Massey University (Albany Campus), Private Bag 102 904, North Shore MSC, Auckland 0745 (New Zealand)

2009-07-15T23:59:59.000Z

420

Optimizing the stroke of Purcell's rotator, a low Reynolds number swimmer  

E-Print Network [OSTI]

Purcell's rotator is a theoretical low Reynolds number swimmer that can act as a model of more complex natural microorganisms, such as E.coli. Because of the low Reynolds number environment, the swimmer has approximately ...

Hammett, Victoria N. (Victoria Nicole)

2012-01-01T23:59:59.000Z

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


421

Vibrational characteristics of a long and very flexible rotating fixed-free beam  

E-Print Network [OSTI]

The differential eigenvalue problem of a long and very flexible rotating fixed-free beam is studied. This kind of system produces a singular perturbation equation with a turning point. The perturbation factor arises because of the division...

Zarco Cruz, Juan Carlos

2003-01-01T23:59:59.000Z

422

Measurements of the Solid-body Rotation of Anisotropic Particles in 3D Turbulence  

E-Print Network [OSTI]

We introduce a new method to measure Lagrangian vorticity and the rotational dynamics of anisotropic particles in a turbulent fluid flow. We use 3D printing technology to fabricate crosses (two perpendicular rods) and jacks (three mutually perpendicular rods). Time-resolved measurements of their orientation and solid-body rotation rate are obtained from stereoscopic video images of their motion in a turbulent flow between oscillating grids with $R_\\lambda$=$91$. The advected particles have a largest dimension of 6 times the Kolmogorov length, making them a good approximation to anisotropic tracer particles. Crosses rotate like disks and jacks rotate like spheres, so these measurements, combined with previous measurements of tracer rods, allow experimental study of ellipsoids across the full range of aspect ratios. The measured mean square tumbling rate, $\\langle \\dot{p}_i \\dot{p}_i \\rangle$, confirms previous direct numerical simulations that indicate that disks tumble much more rapidly than rods. Measurement...

Marcus, Guy G; Kramel, Stefan; Ni, Rui; Voth, Greg A

2014-01-01T23:59:59.000Z

423

An Extensible System For Physically-based Virtual Camera Control Using Rotational Motion Capture  

E-Print Network [OSTI]

-based, real-time virtual camera control in a commercial 3D software package by means of rotational motion capture. The system described is composed of both programmed physical hardware and a software application. The physical hardware consists of multiple...

Huebel, Robert Shelby

2014-04-24T23:59:59.000Z

424

Parent Stars of Extrasolar Planets. XV. Host Star Rotation Revisited with {\\it Kepler} Data  

E-Print Network [OSTI]

We employed published rotation periods of {\\it Kepler} field stars to test whether stars hosting planets tend to rotate more slowly than stars without known planets. Spectroscopic vsini observations of nearby stars with planets have indicated that they tend to have smaller visni values. We employ data for {\\it Kepler} Objects of Interest (KOIs) from the first 16 quarters of its original mission; stellar parameters are based on the analysis of the first 17 quarters. We confirm that KOI stars rotate more slowly with much greater confidence than we had previously found for nearby stars with planets. Furthermore, we find that stars with planets of all types rotate more slowly, not just stars with giant planets.

Gonzalez, Guillermo

2015-01-01T23:59:59.000Z

425

Low torque hydrodynamic lip geometry for bi-directional rotation seals  

DOE Patents [OSTI]

A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

2011-11-15T23:59:59.000Z

426

Low torque hydrodynamic lip geometry for bi-directional rotation seals  

DOE Patents [OSTI]

A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

2009-07-21T23:59:59.000Z

427

Effects of demagnetizing factors on transient motion of ferrofluid in a uniform rotating magnetic field  

E-Print Network [OSTI]

The mechanisms that lead to bulk flow within a ferrofluid-filled container subjected to a rotating uniform magnetic field are experimentally studied. There are two prevailing theories: spin diffusion theory and flow due ...

Snively, Michael John

2011-01-01T23:59:59.000Z

428

M-DWARF RAPID ROTATORS AND THE DETECTION OF RELATIVELY YOUNG MULTIPLE M-STAR SYSTEMS  

E-Print Network [OSTI]

We have searched the Kepler light curves of ~3900 M-star targets for evidence of periodicities that indicate, by means of the effects of starspots, rapid stellar rotation. Several analysis techniques, including Fourier ...

Swift, J.

429

Spatio-temporal theory of lasing action in optically-pumped rotationally excited molecular gases  

E-Print Network [OSTI]

We investigate laser emission from optically-pumped rotationally excited molecular gases confined in a metallic cavity. To this end, we have developed a theoretical framework able to accurately describe, both in the spatial ...

Chua, Song-Liang

430

Design and operation of a counter-rotating aspirated compressor blowdown test facility  

E-Print Network [OSTI]

A unique counter-rotating aspirated compressor was tested in a blowdown facility at the Gas Turbine Laboratory at MIT. The facility expanded on experience from previous blowdown turbine and blowdown compressor experiments. ...

Parker, David V. (David Vickery)

2005-01-01T23:59:59.000Z

431

A two-phase spherical electric machine for generating rotating uniform magnetic fields  

E-Print Network [OSTI]

This thesis describes the design and construction of a novel two-phase spherical electric machine that generates rotating uniform magnetic fields, known as a fluxball machine. Alternative methods for producing uniform ...

Lawler, Clinton T. (Clinton Thomas)

2007-01-01T23:59:59.000Z

432

Principles and biophysical applications of single particle super-localization and rotational tracking  

SciTech Connect (OSTI)

While conventional Single Particle Tracking (SPT) techniques acquire 2D or 3D trajectories of particle probes, we have developed Single Particle Orientation and Rotational Tracking (SPORT) techniques to extract orientation and rotational information. Combined with DIC microscopy, the SPORT technique has been applied in biophysical studies, including membrane diffusion and intracellular transport. The rotational dynamics of nanoparticle vectors on live cell membranes was recorded and its influence on the fate of these nanoparticle vectors was elucidated. The rotational motions of gold nanorods with various surface modifiers were tracked continuously at a temporal resolution of 5 ms under a DIC microscope. We found that the rotational behaviors of gold nanorod vectors are strongly related to their surface charge, specific surface functional groups, and the availability of receptors on cell membranes. The study of rotational Brownian motion of nanoparticles on cell membranes will lead to a better understanding of the mechanisms of drug delivery and provide guidance in designing surface modification strategies for drug delivery vectors under various circumstances. To characterize the rotation mode of surface functionalized gold nanorods on cell membranes, the SPORT technique is combined with the correlation analysis of the bright and dark DIC intensities. The unique capabilities of visualizing and understanding rotational motions of functionalized nanoparticles on live cell membranes allow us to correlate rotational and translational dynamics in unprecedented detail and provide new insights for complex membrane processes, including electrostatic interactions, ligand-receptor binding, and lateral (confined and hopping) diffusion of membrane receptors. Surface-functionalized nanoparticles interact with the membrane in fundamentally different ways and exhibit distinct rotational modes. The early events of particle-membrane approach and attachment are directly visualized for the first time. The rotational dynamics of cargos in both active directional transport and pausing stages of axonal transport was also visualized using high-speed SPORT with a temporal resolution of 2 ms. Both long and short pauses are imaged, and the correlations between the pause duration, the rotational behaviour of the cargo at the pause, and the moving direction after the pause are established. Furthermore, the rotational dynamics leading to switching tracks are visualized in detail. These first-time observations of cargo's rotational dynamics provide new insights on how kinesin and dynein motors take the cargo through the alternating stages of active directional transport and pause. To improve the localization precision of the SPT technique with DIC microscopy, a precise three-dimensional (3D) localization method of spherical gold nanoparticle probes using model-based correlation coefficient mapping was introduced. To accomplish this, a stack of sample images at different z-positions are acquired, and a 3D intensity profile of the probe serving as the model is used to map out the positions of nanoparticles in the sample. By using this model-based correlation imaging method, precise localization can be achieved in imaging techniques with complicated point spread functions (PSF) such as differential interference contrast (DIC) microscopy. The 3D superlocalization method was applied to tracking gold nanospheres during live endocytosis events. Finally, a novel dual-modality imaging technique has been developed to super-localize a single gold nanorod while providing its orientation and rotational information. The super-localization of the gold nanorod can be accomplished by curve fitting the modified bright-field images generated by one of the two beams laterally shifted by the first Nomarski prism in a DIC microscope. The orientation and rotational information is derived from the DIC images of gold nanorods. The new imaging setup has been applied to study the steric hindrance induced by relatively large cargos in the microtubule gliding assay and to track

Gu, Yan [Ames Laboratory

2013-05-15T23:59:59.000Z

433

Characteristic Count Rate Profiles for a Rotating Modulator Gamma-Ray Imager  

E-Print Network [OSTI]

Rotating modulation is a technique for indirect imaging in the hard x-ray and soft gamma-ray energy bands, which may offer an advantage over coded aperture imaging at high energies. A rotating modulator (RM) consists of a single mask of co-planar parallel slats typically spaced equidistance apart, suspended above an array of circular non-imaging detectors. The mask rotates, temporally modulating the transmitted image of the object scene. The measured count rate profiles of each detector are folded modulo the mask rotational period, and the object scene is reconstructed using pre-determined characteristic modulation profiles. The use of Monte Carlo simulation to derive the characteristic count rate profiles is accurate but computationally expensive; an analytic approach is preferred for its speed of computation. We present both the standard and a new advanced characteristic formula describing the modulation pattern of the RM; the latter is a more robust description of the instrument response developed as part ...

Budden, Brent S; Case, Gary L; Cherry, Michael L

2011-01-01T23:59:59.000Z

434

Turbulent convection in the anelastic rotating sphere : a model for the circulation on the giant planets  

E-Print Network [OSTI]

This thesis studies the dynamics of a rotating compressible gas sphere, driven by internal convection, as a model for the dynamics on the giant planets. We develop a new general circulation model for the Jovian atmosphere, ...

Kaspi, Yohai

2008-01-01T23:59:59.000Z

435

THE BANANA PROJECT. V. MISALIGNED AND PRECESSING STELLAR ROTATION AXES IN CV VELORUM  

E-Print Network [OSTI]

As part of the Binaries Are Not Always Neatly Aligned project (BANANA), we have found that the eclipsing binary CV Velorum has misaligned rotation axes. Based on our analysis of the Rossiter-McLaughlin effect, we find ...

Albrecht, Simon

436

Design of compliant mechanisms for attenuation of unidirectional vibrations in rotational systems  

E-Print Network [OSTI]

The purpose of this research was to generate the knowledge required to design compliant mechanisms that (1) attenuate undesired small-motion angular vibrations in rotational power transmission systems and (2) preserve the ...

Szczesny, Spencer E., 1981-

2005-01-01T23:59:59.000Z

437

Rotational-Vibrational Raman Spectroscopy for Measurements of Thermochemistry in Non-isobaric Environments  

E-Print Network [OSTI]

The present work examines line measurements of pressure, temperature, and density in high speed, non-isobaric flows emanating from an underexpanded jet nozzle. Line images of rotational and vibrational Raman spectra are collected for a 8-mm linear...

Bayeh, Alexander C.

2010-01-14T23:59:59.000Z

438

Perturbation of the ns energy levels of the hydrogen atom in rotationally invariant noncommutative space  

E-Print Network [OSTI]

Noncommutative space which is rotationally invariant is considered. The hydrogen atom is studied in this space. We exactly find the leading term in the asymptotic expansion of the corrections to the $ns$ energy levels over the small parameter of noncommutativity.

Gnatenko, Kh P; Tkachuk, V M

2014-01-01T23:59:59.000Z

439

Asynchronous rotation of Earth-like planets in the habitable zone of lower-mass stars  

E-Print Network [OSTI]

Planets in the habitable zone of lower-mass stars are often assumed to be in a state of tidally synchronized rotation, which would considerably affect their putative habitability. Although thermal tides cause Venus to rotate retrogradely, simple scaling arguments tend to attribute this peculiarity to the massive Venusian atmosphere. Using a global climate model, we show that even a relatively thin atmosphere can drive terrestrial planets' rotation away from synchronicity. We derive a more realistic atmospheric tide model that predicts four asynchronous equilibrium spin states, two being stable, when the amplitude of the thermal tide exceeds a threshold that is met for habitable Earth-like planets with a 1-bar atmosphere around stars more massive than 0.5-0.7Msun. Thus, many recently discovered terrestrial planets could exhibit asynchronous spin-orbit rotation, even with a thin atmosphere.

Leconte, Jérémy; Menou, Kristen; Murray, Norman

2015-01-01T23:59:59.000Z

440

Perturbation of the ns energy levels of the hydrogen atom in rotationally invariant noncommutative space  

E-Print Network [OSTI]

Noncommutative space which is rotationally invariant is considered. The hydrogen atom is studied in this space. We exactly find the leading term in the asymptotic expansion of the corrections to the $ns$ energy levels over the small parameter of noncommutativity.

Kh. P. Gnatenko; Yu. S. Krynytskyi; V. M. Tkachuk

2014-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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

ENVELOPING SEMI-GROUP FOR MINIMAL ROTATIONS ON CUT UP TORI  

E-Print Network [OSTI]

are in general hard to identify, but the special class of topological eigen- values (the ones associatedENVELOPING SEMI-GROUP FOR MINIMAL ROTATIONS ON CUT UP TORI JEAN-BAPTISTE AUJOGUE Abstract

Paris-Sud XI, Université de

442

Geometric Phase Of The Faraday Rotation Of Electromagnetic Waves In Magnetized Plasma  

SciTech Connect (OSTI)

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

Jian Liu and Hong Qin

2011-11-07T23:59:59.000Z

443

Apparatus and method for generating a magnetic field by rotation of a charge holding object  

DOE Patents [OSTI]

A device and a method for the production of a magnetic field using a Charge Holding Object that is mechanically rotated. In a preferred embodiment, a Charge Holding Object surrounding a sample rotates and subjects the sample to one or more magnetic fields. The one or more magnetic fields are used by NMR Electronics connected to an NMR Conductor positioned within the Charge Holding Object to perform NMR analysis of the sample.

Gerald, II, Rex E. (Brookfield, IL); Vukovic, Lela (Westchester, IL); Rathke, Jerome W. (Homer Glenn, IL)

2009-10-13T23:59:59.000Z

444

A mathematical model for the electrodeposition of amorphous alloys on a rotating disk electrode  

E-Print Network [OSTI]

A MATHEMATICAL MODEL FOR THE ELECTRODEPOSITION OF AMORPHOUS ALLOYS ON A ROTATING DISK ELECTRODE A Thesis by SHIUAN CHEN Submitted to the Graduate College of Texas AAcM University in partial fulfillment of the requirement, for the degree... of MASTER OF SCIENCE December 19B6 Major Subject: Chemical Engineering A MATHEMATICAL MODEL FOR THE ELECTRODEPOSITION OF AMORPHOUS ALLOYS ON A ROTATING DISK ELECTRODE A Thesis by SHIUAN CHEN Approved as to style and content by: alph E. White...

Chen, Shiuan

1986-01-01T23:59:59.000Z

445

Main effects of the Earth's rotation on the stationary states of ultra-cold neutrons  

E-Print Network [OSTI]

The relativistic corrections in the Hamiltonian for a particle in a uniformly rotating frame are discussed. They are shown to be negligible in the case of ultra-cold neutrons (UCN) in the Earth's gravity. The effect, on the energy levels of UCN, of the main term due to the Earth's rotation, i.e. the angular-momentum term, is calculated. The energy shift is found proportional to the energy level itself.

Mayeul Arminjon

2007-11-13T23:59:59.000Z

446

Thomas Rotation and Polarised Light: A non-Abelian Geometric Phase in Optics  

E-Print Network [OSTI]

We describe a non-Abelian Berry phase in polarisation optics, suggested by an analogy due to Nityananda between boosts in special relativity and the effect of elliptic dichroism on polarised light. The analogy permits a simple optical realization of the non-Abelian gauge field describing Thomas rotation. We also show how Thomas rotation can be understood geometrically on the Poincar\\'{e} sphere in terms of the Pancharatnam phase.

Joseph Samuel; Supurna Sinha

1997-05-13T23:59:59.000Z

447

Absolute measurement of the viscosity of classical and quantum fluids by rotating-cylinder viscometers  

SciTech Connect (OSTI)

We discuss the use of rotating-cylinder viscometers to determine absolute shear viscosities of classical fluids and of helium II in the context of past and current knowledge of the stability and flow of these fluids between concentric cylinders. We identify a problem in measuring the absolute viscosity when the inner cylinder is rotating and the outer cylinder is at rest. We conclude by discussing the design of viscometers for absolute viscosity measurements in helium I and helium II.

Donnelly, R.J.; LaMar, M.M.

1987-11-01T23:59:59.000Z

448

Analysis and experimental study of a plate-type hydraulic vibration damper for cryogenic rotating machinery  

E-Print Network [OSTI]

ANALYSIS AND EXPERIMENTAL STUDY OF A PLATE-TYPE HYDRAULIC VIBRATION DAMPER FOR CRYOGENIC ROTATING MACHINERY A Thesis by EMMANUEL ANGUSTIA OLAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1991 Major Subject: Mechanical Engineering ANALYSIS AND EXPERIMENTAL STUDY OF A PLATE-TYPE HYDRAULIC VIBRATION DAMPER FOR CRYOGENIC ROTATING MACHINERY A Thesis by EMMANUEL ANGUSTIA OLAN Approved...

Olan, Emmanuel Angustia

1991-01-01T23:59:59.000Z

449

Seismic diagnostics for transport of angular momentum in stars 1. Rotational splittings from the PMS to the RGB  

E-Print Network [OSTI]

Rotational splittings are currently measured for several main sequence stars and a large number of red giants with the space mission Kepler. This will provide stringent constraints on rotation profiles. Our aim is to obtain seismic constraints on the internal transport and surface loss of angular momentum of oscillating solar-like stars. To this end, we study the evolution of rotational splittings from the pre-main sequence to the red-giant branch for stochastically excited oscillation modes. We modified the evolutionary code CESAM2K to take rotationally induced transport in radiative zones into account. Linear rotational splittings were computed for a sequence of $1.3 M_{\\odot}$ models. Rotation profiles were derived from our evolutionary models and eigenfunctions from linear adiabatic oscillation calculations. We find that transport by meridional circulation and shear turbulence yields far too high a core rotation rate for red-giant models compared with recent seismic observations. We discuss several uncert...

Marques, J P; Lebreton, Y; Talon, S; Palacios, A; Belkacem, K; Ouazzani, R -M; Mosser, B; Moya, A; Morel, P; Pichon, B; Mathis, S; Zahn, J -P; Turck-Chièze, S; Nghiem, P A P

2012-01-01T23:59:59.000Z

450

The lithium-rotation correlation for WTTS in Taurus-Auriga  

E-Print Network [OSTI]

Surface lithium abundance and rotation velocity can serve as powerful and mutually complementary diagnostics of interior structure of stars. So far, the processes responsible for the lithium depletion during pre-main sequence evolution are still poorly understood. We investigate whether a correlation exists between equivalent widths of Li (EW(Li)) and rotation period (P$_{rot}$) for Weak-line T Tauri stars (WTTSs). We find that rapidly rotating stars have lower EW(Li) and the fast burning of Li begins at the phase when star's P$_{rot}$ evolves towards 3 days among 0.9M$_\\odot$ to 1.4M$_\\odot$ WTTSs in Taurus-Auriga. Our results support the conclusion by Piau & Turch-Chi\\'eze about a model for lithium depletion with age of the star and by Bouvier et al. in relation to rotation evolution. The turn over of the curve for the correlation between EW(Li) and P$_{rot}$ is at the phase of Zero-Age Main Sequence (ZAMS). The EW(Li) decreases with decreasing P$_{rot}$ before the star reaches the ZAMS, while it decreases with increasing P$_{rot}$ (decreasing rotation velocity) for young low-mass main sequence stars. This result could be explained as an age effect of Li depletion and the rapid rotation does not inhibit Li destruction among low mass PMS stars.

L. F. Xing; J. R. Shi; J. Y. Wei

2006-10-30T23:59:59.000Z

451

Contribution to the study of the resonant rotation in the Solar System  

E-Print Network [OSTI]

This HDR-thesis is devoted to the study of the rotation of the natural satellites of the giant planets and of Mercury. These bodies have a resonant rotation. Most of the natural satellites rotate synchronously, showing the same hemisphere to their parent planet (1:1 spin-orbit resonance). The case of Mercury is unique since its spin rate is exactly 1.5 its mean motion (3:2 spin-orbit resonance). These two configurations are dynamical equilibria, reached after damping of the initial rotation of the relevant bodies. Thus, the rotation quantities are a signature of the interior, in particular of a putative global ocean. This manuscript divides into 3 parts. The first part is devoted to the synchronous resonance. It presents different models of rotation from a fully rigid body to a one with a global subsurfacic ocean. We always consider all the degrees of freedom simultaneously, using analytical and numerical resolutions. These models are applied on Titan, Callisto, Janus, Epimetheus, Mimas, Hyperion, and Io. The...

Noyelles, Benoît

2015-01-01T23:59:59.000Z

452

Analysis of buoyancy and tube rotation relative to the modified chemical vapor deposition process  

SciTech Connect (OSTI)

The secondary flows resulting from buoyancy effects in respect to the MCVD process have been studied in a rotating horizontal tube using a perturbation analysis. The three-dimensional secondary flow fields have been determined at several axial locations in a tube whose temperature varies in both the axial and circumferential directions for different rotational speeds. For small rotational speeds, buoyancy and axial convection are dominant and the secondary flow patterns are different in the regions near and far from the torch. For moderate rotational speeds, the effects of buoyancy, axial and angular convection are all important in the region far from the torch where there is a spiraling secondary flow. For large rotational speeds, only buoyancy and angular convection effects are important and no spiraling secondary motions occurs far downstream. Compared with thermophoresis, the important role of buoyancy in determining particle trajectories in MCVD is presented. As the rotational speed increases, the importance of the secondary flow decreases and the thermophoretic contribution vecomes more important. It is noted that thermophoresis is considered to be the main cause of particle deposition in the MCVD process.

Choi, M.; Lin, Y.T.; Greif, R. (Univ. of California, Berkeley (USA))

1990-11-01T23:59:59.000Z

453

Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking  

E-Print Network [OSTI]

We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can be greatly reduced on the way, by an order of magnitude or more, even when the pre-collapse field strength is substantially below the critical value for dominant cloud support. The efficient magnetic braking is due to the pinched geometry of the magnetic field in the pseudodisk, which strengthens the magnetic field and lengthens the level arm for braking. Both effects enhance the magnetic transport of angular momentum from inside to outside. The excess angular momentum is carried away in a low-speed outflow that has, despite claims made by other workers, little in common with observed bipolar molecular outflows. We discuss the implications of our calculations for the formation of true disks that are supported against gravity by rotation.

A. Allen; Z. Y. Li; F. H. Shu

2003-11-17T23:59:59.000Z

454

Percutaneous Vertebroplasty: Preliminary Experiences with Rotational Acquisitions and 3D Reconstructions for Therapy Control  

SciTech Connect (OSTI)

Percutaneous vertebroplasty (PVP) is carried out under fluoroscopic control in most centers. The exclusion of implant leakage and the assessment of implant distribution might be difficult to assess based on two-dimensional radiographic projection images only. We evaluated the feasibility of performing a follow-up examination after PVP with rotational acquisitions and volumetric reconstructions in the angio suite. Twenty consecutive patients underwent standard PVP procedures under fluoroscopic control. Immediate postprocedure evaluation of the implant distribution in the angio suite (BV 3000; Philips, The Netherlands) was performed using rotational acquisitions (typical parameters for the image acquisition included a 17-cm field-of-view, 200 acquired images for a total angular range of 180{sup o}). Postprocessing of acquired volumetric datasets included multiplanar reconstruction (MPR), maximum intensity projection (MIP), and volume rendering technique (VRT) images that were displayed as two-dimensional slabs or as entire three-dimensional volumes. Image evaluation included lesion and implant assessment with special attention given to implant leakage. Findings from rotational acquisitions were compared to findings from postinterventional CT. The time to perform and to postprocess the rotational acquisitions was in all cases less then 10 min. Assessment of implant distribution after PVP using rotational image acquisition methods and volumetric reconstructions was possible in all patients. Cement distribution and potential leakage sites were visualized best on MIP images presented as slabs. From a total of 33 detected leakages with CT, 30 could be correctly detected by rotational image acquisition. Rotational image acquisitions and volumetric reconstruction methods provided a fast method to control radiographically the result of PVP in our cases.

Hodek-Wuerz, Roman [University Hospital Basel, Department of Radiology, Section of Neuroradiology (Switzerland)], E-mail: hodekr@uhbs.ch; Martin, Jean-Baptiste [University Hospital Geneve, Department of Radiology, Section of Neuroradiology (Switzerland); Wilhelm, Kai [University Hospital of Bonn, Department of Radiology (Germany); Lovblad, Karl O. [University Hospital Geneve, Department of Radiology, Section of Neuroradiology (Switzerland); Babic, Drazenko [Philips Medical System (Netherlands); Rufenacht, Daniel A. [University Hospital Geneve, Department of Radiology, Section of Neuroradiology (Switzerland); Wetzel, Stefan G. [University Hospital Basel, Department of Radiology, Section of Neuroradiology (Switzerland)

2006-10-15T23:59:59.000Z

455

Stellar rotation, binarity, and lithium in the open cluster IC4756  

E-Print Network [OSTI]

An important aspect in the evolutionary scenario of cool stars is their rotation and the rotationally induced magnetic activity and interior mixing. Stars in open clusters are particularly useful tracers for these aspects because of their known ages. We aim to characterize the open cluster IC4756 and measure stellar rotation periods and surface differential rotation for a sample of its member stars. Thirty-seven cluster stars were observed continuously with the CoRoT satellite for 78 days in 2010. Follow-up high-resolution spectroscopy of the CoRoT targets and deep Str\\"omgren $uvby\\beta$ and H$\\alpha$ photometry of the entire cluster were obtained with our robotic STELLA facility and its echelle spectrograph and wide-field imager, respectively. We determined high-precision photometric periods for 27 of the 37 CoRoT targets and found values between 0.155 and 11.4 days. Twenty of these are rotation periods. Twelve targets are spectroscopic binaries of which 11 were previously unknown; orbits are given for six ...

Strassmeier, Klaus G; Granzer, Thomas; Bihain, Gabriel; Weber, Michael; Barnes, Sydney A

2015-01-01T23:59:59.000Z

456

Controlling rotational state distributions using two-pulse stimulated Raman excitation  

SciTech Connect (OSTI)

The femtosecond stimulated Raman process is a versatile technique to excite rotational states in molecules. We demonstrate control over the rotational state population in a sample of NO molecules by varying the time delay between two identical laser pulses. The product of the rotational state distribution is probed by a 1+1 resonance-enhanced multiphoton ionization scheme and simulated quantum mechanically. There is good agreement between theoretical and experimental results. The product in selected quantum states shows an oscillatory dependence on the time delay. Spectral analysis reveals rotational transition energies and the presence of multiple Raman steps. We show that the relative strength of these frequency components can be related to excitation pathways with predominant {delta}J=2 transitions toward higher rotational states. The initial step from J=1/2 involves either {delta}J=1 or {delta}J=2. We find that one can discriminate between two excitation ladders. The results demonstrate the coherent effects of tailoring the shape of an ultrashort excitation pulse.

Meijer, A. S.; Zhang, Y.; Parker, D. H.; Zande, W. J. van der; Gijsbertsen, A.; Vrakking, M. J. J. [Institute of Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, NL-6500 GL Nijmegen (Netherlands); FOM Institute for Atomic and Molecular Physics (AMOLF), Kruislaan 407, 1098 SJ Amsterdam (Netherlands)

2007-08-15T23:59:59.000Z

457

End-effects in rapidly rotating cylindrical Taylor-Couette flow  

E-Print Network [OSTI]

We present numerical simulations of the flow in a rapidly rotating cylindrical annulus. We show that at the rotation rates relevant to the magneto-rotational instability, the flow is strongly constrained by the Taylor-Proudman theorem. As a result, it is controlled almost entirely by the end-plates. We then consider two possible options for minimizing these end-effects, namely (i) simply taking a very long cylinder, and (ii) splitting the end-plates into a series of differentially rotating rings. Regarding option (i), we show that the cylinder would have to be hundreds of times as long as it is wide before end-effects become unimportant in the interior. Since this is clearly not feasible, we turn to option (ii), and show that in order to obtain a smooth angular velocity profile, the end-plates would have to be split into around ten rings. If the end-plates are split into fewer rings, perhaps 3-5, the angular velocity profile will not be smooth, but will instead consist of a series of Stewartson layers at the boundaries from one ring to the next. We suggest therefore that the instabilities one obtains in this system will be the familiar Kelvin-Helmholtz instabilities of these Stewartson layers, rather than the magneto-rotational instability. At best, one might hope to obtain the MRI superimposed on these Kelvin-Helmholtz modes. Any subsequent interpretation of results is thus likely to be quite complicated.

Rainer Hollerbach; Alexandre Fournier

2005-06-03T23:59:59.000Z

458

Dynamics of Scalar Fields in the Background of Rotating Black Holes  

E-Print Network [OSTI]

A numerical study of the evolution of a massless scalar field in the background of rotating black holes is presented. First, solutions to the wave equation are obtained for slowly rotating black holes. In this approximation, the background geometry is treated as a perturbed Schwarzschild spacetime with the angular momentum per unit mass playing the role of a perturbative parameter. To first order in the angular momentum of the black hole, the scalar wave equation yields two coupled one-dimensional evolution equations for a function representing the scalar field in the Schwarzschild background and a second field that accounts for the rotation. Solutions to the wave equation are also obtained for rapidly rotating black holes. In this case, the wave equation does not admit complete separation of variables and yields a two-dimensional evolution equation. The study shows that, for rotating black holes, the late time dynamics of a massless scalar field exhibit the same power-law behavior as in the case of a Schwarzschild background independently of the angular momentum of the black hole.

W. Krivan; P. Laguna; P. Papadopoulos

1996-06-04T23:59:59.000Z

459

Toroidal vs. poloidal magnetic fields in Sun-like stars: a rotation threshold  

E-Print Network [OSTI]

From a set of stellar spectropolarimetric observations, we report the detection of surface magnetic fields in a sample of four solar-type stars, namely HD 73350, HD 76151, HD 146233 and HD 190771. Assuming that the observed variability of polarimetric signal is controlled by stellar rotation, we establish the rotation periods of our targets, with values ranging from 8.8 d (for HD 190771) to 22.7 d (for HD 146233). Apart from rotation, fundamental parameters of the selected objects are very close to the Sun's, making this sample a practical basis to investigate the specific impact of rotation on magnetic properties of Sun-like stars. We reconstruct the large-scale magnetic geometry of the targets as a low-order (l<10) spherical harmonics expansion of the surface magnetic field. From the set of magnetic maps, we draw two main conclusions. (a) The magnetic energy of the large-scale field increases with rotation rate. The increase of chromospheric emission with the mean magnetic field is flatter than observed ...

Petit, P; Solanki, SK; Donati, J-F; Aurière, M; Lignières, F; Morin, J; Paletou, F; Ramírez, J; Catala, C; Fares, R

2008-01-01T23:59:59.000Z

460

Solar internal rotation rate and the latitudinal variation of the tachocline  

E-Print Network [OSTI]

A new set of accurately measured frequencies of solar oscillations are used to infer the rotation rate inside the Sun, as a function of radial distance as well as latitude. We have adopted a regularized least squares technique with iterative refinement for both 1.5D inversion using the splitting coefficients and 2D inversion using individual m splittings. The inferred rotation rate agrees well with earlier estimates showing a shear layer just below the surface and another one around the base of the convection zone. The tachocline or the transition layer where the rotation rate changes from differential rotation in the convection zone to almost latitudinally independent rotation rate in the radiative interior is studied in detail. No compelling evidence for any latitudinal variation in position and width of tachocline is found though it appears that the tachocline probably shifts to slightly larger radial distance at higher latitudes and possibly becomes thicker also. However, these variations are within the estimated errors and more accurate data would be needed to make a definitive statement about latitudinal variations.

H. M. Antia; Sarbani Basu; S. M. Chitre

1997-09-10T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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.


461

A method to discriminate solar and antisolar differential rotation in high-precision light curves  

E-Print Network [OSTI]

Surface differential rotation (DR) is one major ingredient of the magnetic field generation process in the Sun and likely in other stars. The term solar-like differential rotation describes the observation that solar equatorial regions rotate faster than polar ones. The opposite effect of polar regions rotating faster than equatorial ones (termed as antisolar DR) has only been observed in a few stars, although there is evidence from theoretical dynamo models. We present a new method to detect the sign of DR (i.e. solar-like or antisolar DR) by analyzing long-term high-precision light curves with the Lomb-Scargle periodogram.We compute the Lomb-Scargle periodogram and identify a set of significant periods $P_k$, which we associate with active regions located at different latitudes on the the stellar surface. If detectable, the first harmonics ($P_k'$) of these periods were identified to compute their peak-height-ratios $r_k:=h(P_k')/h(P_k)$. Spots rotating at lower latitudes generate less sine-shaped light cur...

Reinhold, T

2015-01-01T23:59:59.000Z

462

Stellar Winds on the Main-Sequence II: the Evolution of Rotation and Winds  

E-Print Network [OSTI]

Aims: We study the evolution of stellar rotation and wind properties for low-mass main-sequence stars. Our aim is to use rotational evolution models to constrain the mass loss rates in stellar winds and to predict how their properties evolve with time on the main-sequence. Methods: We construct a rotational evolution model that is driven by observed rotational distributions of young stellar clusters. Fitting the free parameters in our model allows us to predict how wind mass loss rate depends on stellar mass, radius, and rotation. We couple the results to the wind model developed in Paper I of this series to predict how wind properties evolve on the main-sequence. Results: We estimate that wind mass loss rate scales with stellar parameters as $\\dot{M}_\\star \\propto R_\\star^2 \\Omega_\\star^{1.33} M_\\star^{-3.36}$. We estimate that at young ages, the solar wind likely had a mass loss rate that is an order of magnitude higher than that of the current solar wind. This leads to the wind having a higher density at y...

Johnstone, C P; Brott, I; Lüftinger, T

2015-01-01T23:59:59.000Z

463

Paleomagnetic evidence from land-based and ODP cores for clockwise rotation and northward translation of the Phillippine Sea plate  

SciTech Connect (OSTI)

On-land and deep-sea core paleomagnetic data have been collected from around the Philippine Sea plate. Data from the Palau islands suggest 70{degree} of clockwise rotation and northward translation since the mid-Oligocene. The authors interpret this rotation as a rotation of the West Philippine Sea basin as a whole. New paleomagnetic data from Guam indicate 70{degree} of clockwise rotation and northward translation since the early Oligocene. Although Eocene results have been previously quoted, the new data suggest that there is no reliable Eocene data from Guam. New data from Saipan suggest 50-60{degree} of clockwise rotation since the Late Eocene and 20{degree} of clockwise rotation since the mid-Miocene, along with northward translation. During ODP Leg 126, a new technique utilizing the formation microscanner logging tool was employed to obtain orientated drill cores from the Bonin forearc basin. Preliminary results indicate that 70-110{degree} of clockwise rotation has occurred there since the mid-Oligocene. Inclination studies on cores from ODP Legs 125 and 126 along with the on-land paleomagnetic data support 15{degree} of northward translation of the Philippine Sea plate since the mid-Oligocene. The consistent clockwise rotations found around the Philippine Sea plate suggest that the entire plate, including the Bonin and Mariana arcs, has rotated more than 50{degree} since the mid-Oligocene. The similarity of Oligocene results from the Bonin forearc and Guam suggest that little or no relative rotation has occurred between these two points. This implies that the shape of the Mariana arc is probably not due to rotational deformation. The northward translation and clockwise rotation of the Philippine Sea plate established oblique subduction along the proto-Philippine margin, which could account for the 600 km of subducted slab beneath the eastern Celebes Sea.

Cisowski, S.M.; Fuller, M.; Haston, R.B.; Koyama, M. (Univ. of California, Santa Barbara (USA))

1990-06-01T23:59:59.000Z

464

Evaluation of solar radiation measurement systems: EPRI/NREL final test report. Volume 1  

SciTech Connect (OSTI)

Measured solar radiation resource data are needed by electric utilities to evaluate the potential of renewable energy options like photovoltaics in their service territory. In this final test report, we document a cooperative project of the Electric Power Research Institute (EPRI) and the National Renewable Energy Laboratory (NREL) to compare available measurement system options for performing solar radiation resource assessments. We present the detailed results of a 6-month field comparison of thermopile-based pyranometer and pyrheliometer solar irradiance measurement systems with two different implementations of the rotating shadowband radiometer (RSR) concept installed at NREL`s Solar Radiation Research Laboratory (SRRL) in Golden, Colorado.

Stoffel, T.; Riordan, C.; Bigger, J.

1992-11-01T23:59:59.000Z

465

Evaluation of Radiometers Deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory  

SciTech Connect (OSTI)

This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances and direct normal irradiances. These include pyranometers, pyrheliometers, rotating shadowband radiometers, and a pyranometer with fixed internal shading and are all deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. Data from 32 global horizontal irradiance and 19 direct normal irradiance radiometers are presented. The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference global horizontal irradiances and direct normal irradiances.

Habte, A.; Wilcox, S.; Stoffel, T.

2014-02-01T23:59:59.000Z

466

Surface--micromachined rotatable member having a low-contact-area hub  

DOE Patents [OSTI]

A surface-micromachined rotatable member formed on a substrate and a method for manufacturing thereof are disclosed. The surface-micromachined rotatable member, which can be a gear or a rotary stage, has a central hub, and an annulus connected to the central hub by an overarching bridge. The hub includes a stationary axle support attached to the substrate and surrounding an axle. The axle is retained within the axle support with an air-gap spacing therebetween of generally 0.3 .mu.m or less. The rotatable member can be formed by alternately depositing and patterning layers of a semiconductor (e.g. polysilicon or a silicon-germanium alloy) and a sacrificial material and then removing the sacrificial material, at least in part. The present invention has applications for forming micromechanical or microelectromechanical devices requiring lower actuation forces, and providing improved reliability.

Rodgers, M. Steven (Albuquerque, NM); Sniegowski, Jeffry J. (Edgewood, NM)

2002-01-01T23:59:59.000Z

467

An explanation for the kHz-QPO twin peaks separation in slow and fast rotators  

E-Print Network [OSTI]

In this Letter we further explore the idea, suggested previously by Klu{\\'z}niak and collaborators, that the high frequency QPOs may be explained as a resonant coupling between the neutron star spin and two epicyclic modes of accretion disk oscillations. We confirm result of Lee, Abramowicz and Klu{\\'z}niak (\\cite{Lee2004}) that the strongest response occurs when the frequency difference of the two modes equals either the spin frequency (for ``slow rotators'') or half of it (for ``fast rotators''). New points discussed in this Letter are: (1) We suggest that the coupling is gravitational, and due to a non-axially symmetric structure of the rotating neutron star. (2) We found that two excited modes may be both connected to vertical oscillations of the disk, and that strong gravity is not needed to excite the modes.

J. Petri

2005-07-07T23:59:59.000Z

468

Rotational State Analysis of AlH$^+$ by Two-Photon Dissociation  

E-Print Network [OSTI]

We perform \\textit{ab initio} calculations needed to predict the cross-section of an experimentally accessible ($1+1'$) resonance-enhanced multiphoton dissociation (REMPD) pathway in AlH$^+$. Experimenting on AlH$^+$ ions held in a radiofrequency Paul trap, we confirm dissociation via this channel with analysis performed using time-of-flight mass spectrometry. We demonstrate the use of REMPD for rotational state analysis, and we measure the rotational distribution of trapped AlH$^+$ to be consistent with the expected thermal distribution. AlH$^+$ is a particularly interesting species for ion trap work because of its electronic level structure, which makes it amenable to proposals for rotational optical pumping, direct Doppler cooling, and single-molecule fluorescence detection. Potential applications of trapped AlH$^+$ include searches for time-varying constants, quantum information processing, and ultracold chemistry studies.

Seck, Christopher M; Lien, Chien-Yu; Stollenwerk, Patrick R; Odom, Brian C

2014-01-01T23:59:59.000Z

469

Microscopic derivation of nuclear rotation-vibration model, axially symmetric case  

E-Print Network [OSTI]

We derive from first principles the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude, and provides microscopic expressions for the interaction operators among the rotation, vibration, and intrinsic motions, for the moment of inertia, vibration mass, and for the deformation variables. The method uses canonical transformations to collective co-ordinates, followed by a constrained variational method, with the associated constraints imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For deformed harmonic oscillator mean-field potentials, these equations are solved in closed forms for the energies, moments of inertia, quadrupole moments and transition...

Gulshani, Parviz

2015-01-01T23:59:59.000Z

470

Seal assembly with anti-rotation pin for high pressure supercritical fluids  

DOE Patents [OSTI]

A seal assembly for sealing a machine with a first chamber and a second chamber is provided. A rotating shaft extends through the first and second chambers, and rotates therein. The seal assembly has a seal housing, a seal ring and a seal pin. The seal housing is positionable in the machine housing. The seal housing has a seal pocket extending into a fluid side thereof, and a housing receptacle extending into an inner diameter thereof at the seal pocket. The seal ring is positionable in the seal pocket of the seal housing for forming a seal therewith. The seal ring has a ring receptacle extending into an outer diameter thereof. The ring receptacle is positionable adjacent to the housing receptacle for defining a pin hole therebetween. The seal pin is loosely positionable in the pin hole whereby movement about the seal ring is accommodated while preventing rotation thereof.

Wright, Steven A.; Fuller, Robert L.

2014-08-05T23:59:59.000Z

471

Method and apparatus for separating continuous cast strip from a rotating substrate  

DOE Patents [OSTI]

The continuous casting of strip, ribbon and wire is improved by using a free jet nozzle which provides a fluid that follows a rotating substrate surface to the separation point. The nozzle includes an inclined surface having a ratio of its length to the gap between the substrate and the nozzle edge of 5:1 to 15:1. The inclined surface improves the ability of the jet to tangentially follow the substrate in a direction opposite to its rotation to the separation point. This also allows a close positioning of the nozzle to the substrate which serves to provide a back-up mechanical separation means by using the edge of nozzle lip. The nozzle may be rotated from its operating position for cleaning of the substrate and the nozzle.

King, Edward L. (Trenton, OH); Follstaedt, Donald W. (Middletown, OH); Sussman, Richard C. (West Chester, OH)

1991-01-01T23:59:59.000Z

472

Method and apparatus for separating continuous cast strip from a rotating substrate  

DOE Patents [OSTI]

The continuous casting of strip, ribbon and wire is improved by using a free jet nozzle which provides a fluid that follows a rotating substrate surface to the separation point. The nozzle includes an inclined surface having a ratio of its length to the gap between the substrate and the nozzle edge of 5:1 to 15:1. The inclined surface improves the ability of the jet to tangentially follow the substrate in a direction opposite to its rotation to the separation point. This also allows a close positioning of the nozzle to the substrate which serves to provide a back-up mechanical separation means by using the edge of nozzle lip. The nozzle may be rotated from its operating position for cleaning of the substrate and the nozzle. 4 figures.

King, E.L.; Follstaedt, D.W.; Sussman, R.C.

1991-08-20T23:59:59.000Z

473

Giant quadrupole resonance in rotating light nuclei in the calcium region  

SciTech Connect (OSTI)

The quadrupole vibrations of rotating light nuclei around calcium are analyzed in the framework of the Fermi liquid drop model. The input parameters of shape and deformation are those obtained by the Mottelson-Nilsson method for the rotating light nuclei. The surface diffuseness and its changes with spin which could affect the giant resonances in the light nuclei are automatically taken care of in this method. The experimental energies of the giant quadrupole resonance are reproduced in the Fermi liquid drop model for the nonrotating case. The rotation produces the expected splitting of the giant quadrupole resonance modes with the appearance of soft modes. The nature of such splitting may explain the observed changes in the widths of giant resonances at high spins.

Shanmugam, G.; Ramamurthi, K.; Kamalaharan, B.

1986-07-01T23:59:59.000Z

474

Surface-micromachined rotatable member having a low-contact-area hub  

SciTech Connect (OSTI)

A surface-micromachined rotatable member formed on a substrate and a method for manufacturing thereof are disclosed. The surface-micromachined rotatable member, which can be a gear or a rotary stage, has a central hub, and an annulus connected to the central hub by an overarching bridge. The hub includes a stationary axle support attached to the substrate and surrounding an axle. The axle is retained within the axle support with an air-gap spacing therebetween of generally 0.3 .mu.m or less. The rotatable member can be formed by alternately depositing and patterning layers of a semiconductor (e.g. polysilicon or a silicon-germanium alloy) and a sacrificial material and then removing the sacrificial material, at least in part. The present invention has applications for forming micromechanical or microelectromechanical devices requiring lower actuation forces, and providing improved reliability.

Rodgers, M. Steven; Sniegowski, Jeffry J.; Krygowski, Thomas W.

2003-11-18T23:59:59.000Z

475

Rigid-body rotation of an electron cloud in divergent magnetic fields  

SciTech Connect (OSTI)

For a given voltage across a divergent poloidal magnetic field, two electric potential distributions, each supported by a rigid-rotor electron cloud rotating with a different frequency, are found analytically. The two rotation frequencies correspond to the slow and fast rotation frequencies known in uniform plasma. Due to the centrifugal force, the equipotential surfaces, that correspond to the two electric potential distributions, diverge more than the magnetic surfaces do, the equipotential surfaces in the fast mode diverge largely in particular. The departure of the equipotential surfaces from the magnetic field surfaces may have a significant focusing effect on the ions accelerated by the electric field. The focusing effect could be important for laboratory plasma accelerators as well as for collimation of astrophysical jets.

Fruchtman, A. [H.I.T.—Holon Institute of Technology, Holon 58102 (Israel)] [H.I.T.—Holon Institute of Technology, Holon 58102 (Israel); Gueroult, R.; Fisch, N. J. [Princeton Plasma Physics Laboratory, Princeton University, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, New Jersey 08543 (United States)

2013-07-15T23:59:59.000Z

476

Tidal deformation of a slowly rotating material body. I. External metric  

E-Print Network [OSTI]

We construct the external metric of a slowly rotating, tidally deformed material body in general relativity. The tidal forces acting on the body are assumed to be weak and to vary slowly with time, and the metric is obtained as a perturbation of a background metric that describes the external geometry of an isolated, slowly rotating body. The tidal environment is generic and characterized by two symmetric-tracefree tidal moments E_{ab} and B_{ab}, and the body is characterized by its mass M, its radius R, and a dimensionless angular-momentum vector \\chi^a environment requires the introduction of four new quantities, which we designate as rotational-tidal Love numbers. All these Love numbers are gauge ...

Landry, Philippe

2015-01-01T23:59:59.000Z

477

Interaction between Faraday rotation and Cotton-Mouton effects in polarimetry modeling for NSTX  

SciTech Connect (OSTI)

The evolution of electromagnetic wave polarization is modeled for propagation in the major radial direction in the National Spherical Torus Experiment with retroreflection from the center stack of the vacuum vessel. This modeling illustrates that the Cotton-Mouton effect-elliptization due to the magnetic field perpendicular to the propagation direction-is shown to be strongly weighted to the high-field region of the plasma. An interaction between the Faraday rotation and Cotton-Mouton effects is also clearly identified. Elliptization occurs when the wave polarization direction is neither parallel nor perpendicular to the local transverse magnetic field. Since Faraday rotation modifies the polarization direction during propagation, it must also affect the resultant elliptization. The Cotton-Mouton effect also intrinsically results in rotation of the polarization direction, but this effect is less significant in the plasma conditions modeled. The interaction increases at longer wavelength and complicates interpretation of polarimetry measurements.

Zhang, J.; Crocker, N. A.; Carter, T. A.; Kubota, S.; Peebles, W. A. [Department of Physics and Astronomy, UCLA, Los Angeles, California 90095-1547 (United States)

2010-10-15T23:59:59.000Z

478

Collisionality Scaling of Main-ion Toroidal and Poloidal Rotation in Low Torque DIII-D Plasmas  

SciTech Connect (OSTI)

In tokamak plasmas with low levels of toroidal rotation, the radial electric fi eld Er is a combination of pressure gradient and toroidal and poloidal rotation components, all having similar magnitudes. In order to assess the validity of neoclassical poloidal rotation theory for determining the poloidal rotation contribution to Er , D? emission from neutral beam heated tokamak discharges in DIII-D [J.L. Luxon, Nucl. Fusion 42 , 614 (2002)] has been evaluated in a sequence of low torque (electron cyclotron resonance heating and balanced diagnostic neutral beam pulse) discharges to determine the local deuterium toroidal rotation velocity. By invoking the radial force balance relation the deuterium poloidal rotation can be inferred. It is found that the deuterium poloidal low exceeds the neoclassical value in plasmas with collisionality #23;#3; ?i < 0: 1, being more ion diamagnetic, and with a stronger dependence on collisionality than neoclassical theory predicts. At low toroidal rotation, the poloidal rotation contribution to the radial electric fi eld and its shear is signi cant. The eff ect of anomalous levels of poloidal rotation on the radial electric fi eld and cross fi eld heat transport is investigated for ITER parameters.

B A Grierson, et al

2013-05-10T23:59:59.000Z

479

Three-dimensional analytic probabilities of coupled vibrational-rotational-translational energy transfer for DSMC modeling of nonequilibrium flows  

SciTech Connect (OSTI)

A three-dimensional, nonperturbative, semiclassical analytic model of vibrational energy transfer in collisions between a rotating diatomic molecule and an atom, and between two rotating diatomic molecules (Forced Harmonic Oscillator–Free Rotation model) has been extended to incorporate rotational relaxation and coupling between vibrational, translational, and rotational energy transfer. The model is based on analysis of semiclassical trajectories of rotating molecules interacting by a repulsive exponential atom-to-atom potential. The model predictions are compared with the results of three-dimensional close-coupled semiclassical trajectory calculations using the same potential energy surface. The comparison demonstrates good agreement between analytic and numerical probabilities of rotational and vibrational energy transfer processes, over a wide range of total collision energies, rotational energies, and impact parameter. The model predicts probabilities of single-quantum and multi-quantum vibrational-rotational transitions and is applicable up to very high collision energies and quantum numbers. Closed-form analytic expressions for these transition probabilities lend themselves to straightforward incorporation into DSMC nonequilibrium flow codes.

Adamovich, Igor V. [Nonequilibrium Thermodynamics Laboratory, Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)] [Nonequilibrium Thermodynamics Laboratory, Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)

2014-04-15T23:59:59.000Z

480

Bridging the gap between the Jaynes-Cummings and Rabi models using an intermediate rotating wave approximation  

E-Print Network [OSTI]

We present a novel approach called the intermediate rotating wave approximation (IRWA), which employs a time-averaging method to encapsulate the dynamics of light-matter interaction from strong to ultrastrong coupling regime. In contrast to the ordinary rotating wave approximation, this method addresses the co-rotating and counter-rotating terms separately to trace their physical consequences individually, and thus establishes the continuity between the Jaynes-Cummings model and the quantum Rabi model. We investigate IRWA in near resonance and large detuning cases. Our IRWA not only agrees well with both models in their respective coupling strengths, but also offers a good explanation for their differences.

Yimin Wang; Jing Yan Haw

2015-02-10T23:59:59.000Z

Note: This page contains sample records for the topic "rotating shadowband spectroradiometer" 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.


481

Rotating-frame gradient fields for magnetic resonance imaging and nuclear magnetic resonance in low fields  

DOE Patents [OSTI]

A system and method for Fourier encoding a nuclear magnetic resonance (NMR) signal is disclosed. A static magnetic field B.sub.0 is provided along a first direction. An NMR signal from the sample is Fourier encoded by applying a rotating-frame gradient field B.sub.G superimposed on the B.sub.0, where the B.sub.G comprises a vector component rotating in a plane perpendicular to the first direction at an angular frequency .omega.in a laboratory frame. The Fourier-encoded NMR signal is detected.

Bouchard, Louis-Serge; Pines, Alexander; Demas, Vasiliki

2014-01-21T23:59:59.000Z

482

An apparatus to measure fourth sound interactions with helium II in rotation  

E-Print Network [OSTI]

AN APPARATUS TO MEASURE FOURTH SOUND INTERACTIONS WITH HELIUM II IN ROTATION A Thesis oy Stephen Eller Burrin Subt ittud to the Oraduate College of Texas ASM University in partial fulfillnient of the requirement for the degree of STER... OF SCIENCE August 1968 vmjor Subject: Physics AiiPARATES C "EASi'RE EOf;R LI RONNE INTERACTIONS ffIT?f ?fELI3I f II IN ROTATION A I icsia Stepfien Eller Iurrin ctyle and content by: Ef. ;ii-ei"n o Ooairiittee y f Reao o e, resent i'fember / i...

Burrin, Stephen Eller

1968-01-01T23:59:59.000Z

483

Cosmological Rotation of Quantum-Mechanical Origin and Anisotropy of the Microwave Background  

E-Print Network [OSTI]

It is shown that rotational cosmological perturbations can be generated in the early Universe, similarly to gravitational waves. The generating mechanism is quantum-mechanical in its nature, and the created perturbations should now be placed in squeezed vacuum quantum states. The physical conditions under which the phenomenon can occur are formulated. The generated perturbations can contribute to the large-angular-scale anisotropy of the cosmic microwave background radiation. An exact formula is derived for the angular correlation function of the temperature variations caused by the quantum-mechanically generated rotational perturbations. The multipole expansion begins from the dipole component. The comparison with the case of gravitational waves is made.

L. P. Grishchuk

1993-10-06T23:59:59.000Z

484

Rotational crossbreeding as a system for beef production in the Gulf Coast region of Texas  

E-Print Network [OSTI]

ROTATIONAL CROSSBREEDING AS A SYSTEM FOR BEEF PRODUCTION IN THE GULF COAST REGION OF TEXAS A Thesis by MELVIN DELL YOUNG Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree...: irman of Committ Member Head o epar nt Member ABSTRACT Rotational Crossbreeding as a System for Beef Production in the Gulf Coast Region of Texas. (August 1974) Melvin Dell Young, B. S. , Texas A8M Unl versi ty CHAIRMAN OF ADVISORY COMMITTEE: J. K...

Young, Melvin Dell

1974-01-01T23:59:59.000Z

485

Jet impingement heat transfer in two-pass rotating rectangular channels  

E-Print Network [OSTI]

temperature of the blade material. Since the turbine blades are the next component downstream of the combustor, they must be cooled effectively to keep from burning out. The coolant for these blades is mostly air extracted &om the compressor of the engine...(Outward Flow) Coolant Supply(Inward Flow) Figure 3 Cross sectional view of jet impingement cooling in two-pass rotating channel However, the spent jets in rotation make the channel arrangement favor channel heat transfer &om the suction and pressure surfaces...

Zhang, Yuming

1996-01-01T23:59:59.000Z

486

Gamma-ray imaging with a rotating hexagonal uniformly redundant array  

SciTech Connect (OSTI)

Laboratory experiments have been performed to demonstrate the capabilities of a ..gamma..-ray imaging system employing a NaI Anger camera and a rotating coded aperture mask. The mask incorporates in its design a new type of hexagonal uniformly redundant array (HURA) which is essentially antisymmetric under 60/sup 0/ rotation. The image formation techniques are described and results are presented that demonstrate the imaging capability of the system for individual and multiple point sources of ..gamma..-ray emission. The results are compared to analytical predictions for the imaging and point source localization capabilities of coded aperture systems using continuous detectors.

Cook, W.R.; Finger, M.; Prince, T.A.; Stone, E.C.

1984-02-01T23:59:59.000Z

487

Gamma-Ray Bursts and Afterglows from Rotating Strange Stars and Neutron Stars  

E-Print Network [OSTI]

We here discuss a new model of $\\gamma$-ray bursts (GRBs) based on differentially rotating strange stars. Strange stars in this model and differentially rotating neutron stars in the Klu\\'zniak-Ruderman model can produce extremely relativistic, variable fireballs required by GRBs and then become millisecond pulsars. The effect of such pulsars on expansion of the postburst fireballs through magnetic dipole radiation is studied. We show that these two models can explain naturally not only various features of GRBs but also light curves of afterglows.

Z. G. Dai; T. Lu

1998-10-21T23:59:59.000Z

488

Dispersed Phase of Non-Isothermal Particles in Rotating Turbulent Flows  

E-Print Network [OSTI]

We suggest certain effects, caused by interaction between rotation and gravitation with turbulence structure, for the cooling/heating of dispersed phase of non-isothermal particles in rotating turbulent fluid flows. These effects are obtained through the derivation of kinetic or probability density function based macroscopic equations for the particles. In doing so, for one-way temperature coupling, we also show that homogeneous, isotropic non-isothermal fluid turbulence does not influence the mean temperature (though it influences mean velocity) of the dispersed phase of particles settling due to gravitational force in the isotropic turbulence.

Pandya, R V R

2015-01-01T23:59:59.000Z

489

Optical trapping and rotation of airborne absorbing particles with a single focused laser beam  

SciTech Connect (OSTI)

We measure the periodic circular motion of single absorbing aerosol particles that are optically trapped with a single focused Gaussian beam and rotate around the laser propagation direction. The scattered light from the trapped particle is observed to be directional and change periodically at 0.4–20?kHz. The instantaneous positions of the moving particle within a rotation period are measured by a high-speed imaging technique using a charge coupled device camera and a repetitively pulsed light-emitting diode illumination. The centripetal acceleration of the trapped particle as high as ?20 times the gravitational acceleration is observed and is attributed to the photophoretic forces.

Lin, Jinda; Li, Yong-qing, E-mail: liy@ecu.edu [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)] [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)

2014-03-10T23:59:59.000Z

490

THE UNIQUENESS THEOREM FOR ROTATING BLACK HOLE SOLUTIONS OF SELF-GRAVITATING HARMONIC MAPPINGS  

E-Print Network [OSTI]

We consider rotating black hole configurations of self-gravitating maps from spacetime into arbitrary Riemannian manifolds. We first establish the integrability conditions for the Killing fields generating the stationary and the axisymmetric isometry (circularity theorem). Restricting ourselves to mappings with harmonic action, we subsequently prove that the only stationary and axisymmetric, asymptotically flat black hole solution with regular event horizon is the Kerr metric. Together with the uniqueness result for non-rotating configurations and the strong rigidity theorem, this establishes the uniqueness of the Kerr family amongst all stationary black hole solutions of self-gravitating harmonic mappings.

M. Heusler

1995-03-28T23:59:59.000Z

491

Investigation of Terahertz Vibration-Rotation Tunneling Spectra for the Water Octamer  

E-Print Network [OSTI]

Investigation of Terahertz Vibration-Rotation Tunneling Spectra for the Water Octamer Jeremy O, and Richard J. Saykally*, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom Department of Chemistry, University of California, Berkeley, California 94720

Cohen, Ronald C.

492

On the invertibility of the XOR rotations of a binary word  

E-Print Network [OSTI]

We prove the following result regarding operations on a binary word whose length is a power of two: computing the exclusive-or of a number of rotated versions of the word is an invertible (one-to-one) operation if and only ...

Rivest, Ronald L.

493

Fiber optic sensor system for detecting movement or position of a rotating wheel bearing  

DOE Patents [OSTI]

An improved fiber optic sensor system and integrated sensor bearing assembly for detecting movement or position of a rotating wheel bearing having a multi-pole tone ring which produces an alternating magnetic field indicative of movement and position of the rotating member. A magneto-optical material, such as a bismuth garnet iron (B.I.G.) crystal, having discrete magnetic domains is positioned in the vicinity of the tone ring so that the domains align themselves to the magnetic field generated by the tone ring. A single fiber optic cable, preferably single mode fiber, carries light generated by a source of light to the B.I.G. crystal. The light passes through the B.I.G. crystal and is refracted at domain boundaries in the crystal. The intensity of the refracted light is indicative of the amount of alignment of the domains and therefore the strength of the magnetic field. The refracted light is carried by the fiber optic cable to an optic receiver where the intensity is measured and an electrical signal is generated and sent to a controller indicating the frequency of the changes in light intensity and therefore the rotational speed of the rotating wheel bearing.

Veeser, Lynn R. (Los Alamos, NM); Rodriguez, Patrick J. (Santa Fe, NM); Forman, Peter R. (Los Alamos, NM); Monahan, Russell E. (Ann Arbor, MI); Adler, Jonathan M. (Ypsilanti, MI)

1997-01-01T23:59:59.000Z

494

Empirical Earth rotation model: a consistent way to evaluate Earth orientation parameters  

E-Print Network [OSTI]

It is customary to perform analysis of the Earth's rotation in two steps: first, to present results of estimation of the Earth orientation parameters in the form of time series based on a simplified model of variations of the Earth's rotation for a short period of time, and then to process this time series of adjustments by applying smoothing, re-sampling and other numerical algorithms. Although this approach saves computational time, it suffers from self-inconsistency: total Earth orientation parameters depend on a subjective choice of the apriori Earth orientation model, cross-correlations between points of time series are lost, and results of an operational analysis per se have a limited use for end users. An alternative approach of direct estimation of the coefficients of expansion of Euler angle perturbations into basis functions is developed. These coefficients describe the Earth's rotation over entire period of observations and are evaluated simultaneously with station positions, source coordinates and other parameters in a single LSQ solution. In the framework of this approach considerably larger errors in apriori EOP model are tolerated. This approach gives a significant conceptual simplification of representation of the Earth's rotation.

L. Petrov

2006-11-26T23:59:59.000Z

495

Thermodynamics of a rotating black hole in minimal five-dimensional gauged supergravity  

E-Print Network [OSTI]

In this article we study the thermodynamics of a general non-extremal rotating black hole in minimal five-dimensional gauged supergravity. We analyse the entropy-temperature diagram and the free energy. Additionally we consider the thermodynamic stability by calculating the specific heat, the isothermal moment of inertia tensor and the adiabatic compressibility.

Saskia Grunau; Hendrik Neumann

2015-02-24T23:59:59.000Z

496

Electro/Magnetically Induced Controllable Rotation In Small-scale Liquid Flow  

E-Print Network [OSTI]

We study all the possibilities of producing rotating flow in an incompressible fluid by electric and magnetic fields. We start with a general theoretical basis and look for different configurations and set-ups which electric/magnetic field and an electric current affect the vorticity of fluid resulting in rotation on liquid flow. We assume steady-state conditions and time-independent electric and magnetic fields as the external body torque. Regarding the theoretical basis, we propose three experimental set-ups in which by applying fields on a fluid, rotational vortices are produced: (a) a uniform electric field and a uniform electric current, (b) a uniform electric current and a non-uniform magnetic field, and (c) a non-uniform electric current and a uniform magnetic field. The first case has been reported in detail named "Liquid Film Motor". The two other cases are experimentally investigated here for a cubic an cylindrical cells. The rotational velocity patterns are obtained by PIV technique, and the result...

Amjadi, A; Sobhani, S O; Shirsavar, R

2013-01-01T23:59:59.000Z

497

NUMERICAL STUDY OF FLOW STREAM IN A MINI VAWT WITH RELATIVE ROTATING BLADES  

E-Print Network [OSTI]

, performance coefficient, unsteady simulation, VAWT, vertical axis, wind energy, pitch controlled bladesNUMERICAL STUDY OF FLOW STREAM IN A MINI VAWT WITH RELATIVE ROTATING BLADES Bayeul-Lainé Annie.dockter- 9@etudiants.ensam.eu,gerard.bois@ensam.eu Abstract Today, wind energy is mainly used to generate

Paris-Sud XI, Université de

498

Experimental testing of the variable rotated elastic parabolic Harry J. Simpsona)  

E-Print Network [OSTI]

Experimental testing of the variable rotated elastic parabolic equation Harry J. Simpsona) Physical Street, Golden, Colorado 80401 Raymond J. Soukup Acoustics Division Code 7144, Naval Research Laboratory and the ability of the model to produce benchmark-quality agreement with experimental data [J. M. Collis et al., J

499

LBNL-41149 1 Resonant Magneto-Optical Rotation: New Twists in an Old Plot  

E-Print Network [OSTI]

LBNL-41149 1 Resonant Magneto-Optical Rotation: New Twists in an Old Plot Dmitry Budkera dispersion #12;LBNL-41149 2 curves) are sketched in Fig. 2. A characteristic width of these curves in the limit of large fields (Fig. 3). #12;LBNL-41149 3 This elementary discussion essentially summarizes

Budker, Dmitry

500

RAPID SUNSPOT ROTATION ASSOCIATED WITH THE X2.2 FLARE ON 2011 FEBRUARY 15  

SciTech Connect (OSTI)

We present observations of sunspot evolution associated with the first X-class flare of the present solar cycle 24, which occurred in AR 11158 on 2011 February 15. The active region consisted of four emerging bipoles that showed complicated sunspot motion. The preceding spot of a bipole underwent the fastest movement. It not only passed through the following end of another bipole, thus causing a shearing motion, but also merged with the