National Library of Energy BETA

Sample records for maximum variable observations

  1. Speech processing using conditional observable maximum likelihood continuity mapping

    DOE Patents [OSTI]

    Hogden, John; Nix, David

    2004-01-13

    A computer implemented method enables the recognition of speech and speech characteristics. Parameters are initialized of first probability density functions that map between the symbols in the vocabulary of one or more sequences of speech codes that represent speech sounds and a continuity map. Parameters are also initialized of second probability density functions that map between the elements in the vocabulary of one or more desired sequences of speech transcription symbols and the continuity map. The parameters of the probability density functions are then trained to maximize the probabilities of the desired sequences of speech-transcription symbols. A new sequence of speech codes is then input to the continuity map having the trained first and second probability function parameters. A smooth path is identified on the continuity map that has the maximum probability for the new sequence of speech codes. The probability of each speech transcription symbol for each input speech code can then be output.

  2. OBSERVATIONS OF THERMAL FLARE PLASMA WITH THE EUV VARIABILITY EXPERIMENT

    SciTech Connect (OSTI)

    Warren, Harry P.; Doschek, George A. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Mariska, John T. [School of Physics, Astronomy, and Computational Sciences, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States)

    2013-06-20

    One of the defining characteristics of a solar flare is the impulsive formation of very high temperature plasma. The properties of the thermal emission are not well understood, however, and the analysis of solar flare observations is often predicated on the assumption that the flare plasma is isothermal. The EUV Variability Experiment (EVE) on the Solar Dynamics Observatory provides spectrally resolved observations of emission lines that span a wide range of temperatures (e.g., Fe XV-Fe XXIV) and allow for thermal flare plasma to be studied in detail. In this paper we describe a method for computing the differential emission measure distribution in a flare using EVE observations and apply it to several representative events. We find that in all phases of the flare the differential emission measure distribution is broad. Comparisons of EVE spectra with calculations based on parameters derived from the Geostationary Operational Environmental Satellites soft X-ray fluxes indicate that the isothermal approximation is generally a poor representation of the thermal structure of a flare.

  3. Lack of uniform trends but increasing spatial variability in observed Indian rainfall extremes

    SciTech Connect (OSTI)

    Ghosh, Subimal [ORNL; Das, Debasish [ORNL; Kao, Shih-Chieh [ORNL; Ganguly, Auroop R [ORNL

    2012-01-01

    Recent studies disagree on how rainfall extremes over India have changed in space and time over the past half century, as well as on whether the changes observed are due to global warming or regional urbanization. Although a uniform and consistent decrease in moderate rainfall has been reported, a lack of agreement about trends in heavy rainfall may be due in part to differences in the characterization and spatial averaging of extremes. Here we use extreme value theory to examine trends in Indian rainfall over the past half century in the context of long-term, low-frequency variability.We show that when generalized extreme value theory is applied to annual maximum rainfall over India, no statistically significant spatially uniform trends are observed, in agreement with previous studies using different approaches. Furthermore, our space time regression analysis of the return levels points to increasing spatial variability of rainfall extremes over India. Our findings highlight the need for systematic examination of global versus regional drivers of trends in Indian rainfall extremes, and may help to inform flood hazard preparedness and water resource management in the region.

  4. Amplitude Variability in gamma Dor and delta Sct Stars Observed by Kepler

    SciTech Connect (OSTI)

    Guzik, Joyce Ann; Kosak, Mary Katherine; Bradley, Paul Andrew; Jackiewicz, Jason

    2015-08-17

    The NASA Kepler spacecraft data revealed a large number of new multimode nonradially pulsating gamma Dor and delta Sct variable stars. The Kepler high-precision long time-series photometry makes it possible to study amplitude variations of the frequencies, and recent literature on amplitude and frequency variations in nonradially pulsating variables is summarized. Several methods are applied to study amplitude variability in about a dozen gamma Doradus or delta Scuti candidate variable stars observed for several quarters as part of the Kepler Guest Observer program. The magnitude and timescale of the amplitude variations are discussed, along with the presence or absence of correlations between amplitude variations for different frequencies of a given star. Proposed causes of amplitude spectrum variability that will require further investigation are also discussed.

  5. Pulsations and period changes of the non-Blazhko RR lyrae variable Y oct observed from Dome A, Antarctica

    SciTech Connect (OSTI)

    Zhihua, Huang; Jianning, Fu; Weikai, Zong; Lingzhi, Wang; Zonghong, Zhu; M, Macri Lucas; Lifan, Wang; Ashley, Michael C. B.; S, Lawrence Jon; Daniel, Luong-Van; Xiangqun, Cui; Long-Long, Feng; Xuefei, Gong; Qiang, Liu; Huigen, Yang; Xiangyan, Yuan; Xu, Zhou; Zhenxi, Zhu; R, Pennypacker Carl; G, York Donald

    2015-01-01

    During the operation of the Chinese Small Telescope Array (CSTAR) in Dome A of Antarctica in the years 2008, 2009, and 2010, large amounts of photometric data have been obtained for variable stars in the CSTAR field. We present here the study of one of six RR Lyrae variables, Y Oct, observed with CSTAR in Dome A, Antarctica. Photometric data in the i band were obtained in 2008 and 2010, with a duty cycle (defined as the fraction of time representing scientifically available data to CSTAR observation time) of about 44% and 52%, respectively. In 2009, photometric data in the g and r bands were gathered for this star, with a duty cycle of 65% and 60%, respectively. Fourier analysis of the data in the three bands only shows the fundamental frequency and its harmonics, which is characteristic of the non-Blazhko RR Lyrae variables. Values of the fundamental frequency and the amplitudes, as well as the total pulsation amplitude, are obtained from the data in the three bands separately. The amplitude of the fundamental frequency and the total pulsation amplitude in the g band are the largest, and those in the i band the smallest. Two-hundred fifty-one times of maximum are obtained from the three seasons of data, which are analyzed together with 38 maximum times provided in the GEOS RR Lyrae database. A period change rate of −0.96 ± 0.07 days Myr{sup −1} is then obtained, which is a surprisingly large negative value. Based on relations available in the literature, the following physical parameters are derived: [Fe/H] = −1.41 ± 0.14, M{sub V} = 0.696 ± 0.014 mag, V−K = 1.182 ± 0.028 mag, logT{sub eff} = 3.802 ± 0.003 K, logg = 2.705 ± 0.004, logL/L{sub ⊙} = 1.625 ± 0.013, and logM/M{sub ⊙} = −0.240 ± 0.019.

  6. PHOTOMETRY OF VARIABLE STARS FROM DOME A, ANTARCTICA: RESULTS FROM THE 2010 OBSERVING SEASON

    SciTech Connect (OSTI)

    Wang, Lingzhi; Zhu, Zonghong; Macri, Lucas M.; Wang, Lifan; Ashley, Michael C. B.; Lawrence, Jon S.; Luong-Van, Daniel; Storey, John W. V.; Cui, Xiangqun; Feng, Long-Long; Gong, Xuefei; Liu, Qiang; Shang, Zhaohui; Yang, Huigen; Yang, Ji; Yuan, Xiangyan; Zhou, Xu; Zhu, Zhenxi; Pennypacker, Carl R.; York, Donald G.

    2013-12-01

    We present results from a season of observations with the Chinese Small Telescope ARray, obtained over 183 days of the 2010 Antarctic winter. We carried out high-cadence time-series aperture photometry of 9125 stars with i ?< 15.3 mag located in a 23 deg{sup 2} region centered on the south celestial pole. We identified 188 variable stars, including 67 new objects relative to our 2008 observations, thanks to broader synoptic coverage, a deeper magnitude limit, and a larger field of view. We used the photometric data set to derive site statistics from Dome A. Based on two years of observations, we find that extinction due to clouds at this site is less than 0.1 and 0.4 mag during 45% and 75% of the dark time, respectively.

  7. Observed 20th Century Desert Dust Variability: Impact on Climate and Biogeochemistry

    SciTech Connect (OSTI)

    Mahowald, Natalie; Kloster, Silvia; Engelstaedter, S.; Moore, Jefferson Keith; Mukhopadhyay, S.; McConnell, J. R.; Albani, S.; Doney, Scott C.; Bhattacharya, A.; Curran, M. A. J.; Flanner, Mark G.; Hoffman, Forrest M; Lawrence, David M.; Lindsay, Keith; Mayewski, P. A.; Neff, Jason; Rothenberg, D.; Thomas, E.; Thornton, Peter E; Zender, Charlie S.

    2010-01-01

    Desert dust perturbs climate by directly and indirectly interacting with incoming solar and outgoing long wave radiation, thereby changing precipitation and temperature, in addition to modifying ocean and land biogeochemistry. While we know that desert dust is sensitive to perturbations in climate and human land use, previous studies have been unable to determine whether humans were increasing or decreasing desert dust in the global average. Here we present observational estimates of desert dust based on paleodata proxies showing a doubling of desert dust during the 20th century over much, but not all the globe. Large uncertainties remain in estimates of desert dust variability over 20th century due to limited data. Using these observational estimates of desert dust change in combination with ocean, atmosphere and land models, we calculate the net radiative effect of these observed changes (top of atmosphere) over the 20th century to be -0.14 {+-} 0.11 W/m{sup 2} (1990-1999 vs. 1905-1914). The estimated radiative change due to dust is especially strong between the heavily loaded 1980-1989 and the less heavily loaded 1955-1964 time periods (-0.57 {+-} 0.46 W/m{sup 2}), which model simulations suggest may have reduced the rate of temperature increase between these time periods by 0.11 C. Model simulations also indicate strong regional shifts in precipitation and temperature from desert dust changes, causing 6 ppm (12 PgC) reduction in model carbon uptake by the terrestrial biosphere over the 20th century. Desert dust carries iron, an important micronutrient for ocean biogeochemistry that can modulate ocean carbon storage; here we show that dust deposition trends increase ocean productivity by an estimated 6% over the 20th century, drawing down an additional 4 ppm (8 PgC) of carbon dioxide into the oceans. Thus, perturbations to desert dust over the 20th century inferred from observations are potentially important for climate and biogeochemistry, and our understanding of these changes and their impacts should continue to be refined.

  8. Observation

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

    Velocity-Independent Electron Transport in the Reversed Field Pinch R. O'Connell, * D. J. Den Hartog, C. B. Forest, J. K. Anderson, T. M. Biewer, † B. E. Chapman, D. Craig, G. Fiksel, S. C. Prager, J. S. Sarff, and S. D. Terry ‡ Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA R.W. Harvey CompX, San Diego, California, USA (Received 16 December 2002; published 24 July 2003) Confinement of runaway electrons has been observed for the first time in a reversed

  9. Maximum-likelihood

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

    Maximum-likelihood fitting of data dominated by Poisson statistical uncertainties M. R. Stoneking and D. J. Den Hartog Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 ͑Presented on 15 May 1996͒ The fitting of data by ␹ 2 minimization is valid only when the uncertainties in the data are normally distributed. When analyzing spectroscopic or particle counting data at very low signal level ͑e.g., a Thomson scattering diagnostic͒, the uncertainties are

  10. NON-RADIAL OSCILLATIONS IN M-GIANT SEMI-REGULAR VARIABLES: STELLAR MODELS AND KEPLER OBSERVATIONS

    SciTech Connect (OSTI)

    Stello, Dennis; Compton, Douglas L.; Bedding, Timothy R.; Kiss, Laszlo L.; Bellamy, Beau; Christensen-Dalsgaard, Jrgen; Kjeldsen, Hans; Garca, Rafael A.

    2014-06-10

    The success of asteroseismology relies heavily on our ability to identify the frequency patterns of stellar oscillation modes. For stars like the Sun this is relatively easy because the mode frequencies follow a regular pattern described by a well-founded asymptotic relation. When a solar-like star evolves off the main sequence and onto the red giant branch its structure changes dramatically, resulting in changes in the frequency pattern of the modes. We follow the evolution of the adiabatic frequency pattern from the main sequence to near the tip of the red giant branch for a series of models. We find a significant departure from the asymptotic relation for the non-radial modes near the red giant branch tip, resulting in a triplet frequency pattern. To support our investigation we analyze almost four years of Kepler data of the most luminous stars in the field (late K and early M type) and find that their frequency spectra indeed show a triplet pattern dominated by dipole modes even for the most luminous stars in our sample. Our identification explains previous results from ground-based observations reporting fine structure in the Petersen diagram and sub-ridges in the period-luminosity diagram. Finally, we find ''new ridges'' of non-radial modes with frequencies below the fundamental mode in our model calculations, and we speculate they are related to f modes.

  11. Simultaneous Observations of PKS 2155--304 with H.E.S.S., Fermi, RXTE and ATOM: Spectral Energy Distributions and Variability in a Low State

    SciTech Connect (OSTI)

    Aharonian, F.; Akhperjanian, A.G.; Anton, G.; Barres de Almeida, U.; Bazer-Bachi, A.R.; Becherini, Y.; Behera, B.; Bernlohr, K.; Boisson, C.; Bochow, A.; Borrel, V.; Brion, E.; Brucker, J.; Brun, P.; Buhler, R.; Bulik, T.; Busching, I.; Boutelier, T.; Chadwick, P.M.; Charbonnier, A.; Chaves, R.C.G.; /more authors..

    2009-05-07

    We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155-304. The gamma-ray bands were observed for 11 days, between 2008 August 25 and 2008 September 6 (MJD 54704-54715), jointly with the Fermi Gamma-ray Space Telescope and the HESS atmospheric Cherenkov array, providing the first simultaneous MeV-TeV spectral energy distribution (SED) with the new generation of {gamma}-ray telescopes. The ATOM telescope and the RXTE and Swift observatories provided optical and X-ray coverage of the low-energy component over the same time period. The object was close to the lowest archival X-ray and very high energy (VHE; >100 GeV) state, whereas the optical flux was much higher. The light curves show relatively little ({approx}30%) variability overall when compared to past flaring episodes, but we find a clear optical/VHE correlation and evidence for a correlation of the X-rays with the high-energy spectral index. Contrary to previous observations in the flaring state, we do not find any correlation between the X-ray and VHE components. Although synchrotron self-Compton models are often invoked to explain the SEDs of BL Lac objects, the most common versions of these models are at odds with the correlated variability we find in the various bands for PKS 2155-304.

  12. Removal to Maximum Extent Practical

    Broader source: Energy.gov [DOE]

    Summary Notes from 1 November 2007 Generic Technical Issue Discussion on Removal of Highly Radioactive Radionuclides/Key Radionuclides to the Maximum Extent Practical

  13. Maximum Performance Group MPG | Open Energy Information

    Open Energy Info (EERE)

    Maximum Performance Group MPG Jump to: navigation, search Name: Maximum Performance Group (MPG) Place: College Point, New York Zip: 11356 Product: Technology based energy and asset...

  14. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted...

    Office of Environmental Management (EM)

    PRIME Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by...

  15. Maximum entanglement in squeezed boson and fermion states

    SciTech Connect (OSTI)

    Khanna, F. C.; Malbouisson, J. M. C.; Santana, A. E.; Santos, E. S.

    2007-08-15

    A class of squeezed boson and fermion states is studied with particular emphasis on the nature of entanglement. We first investigate the case of bosons, considering two-mode squeezed states. Then we construct the fermion version to show that such states are maximum entangled, for both bosons and fermions. To achieve these results, we demonstrate some relations involving squeezed boson states. The generalization to the case of fermions is made by using Grassmann variables.

  16. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted...

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

    5, 1, 2 SO2 Case Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 5, 1, 2 SO2 Case Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia:...

  17. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted...

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

    Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 3, 1, 2 SO2 Case. Compliance based on highest, second-highest, short-term, and highest annual...

  18. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted...

    Office of Environmental Management (EM)

    4, 1, 2 SO2 Case Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 4, 1, 2 SO2 Case Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia:...

  19. Oxidation State Optimization for Maximum Efficiency of NOx Adsorber...

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

    State Optimization for Maximum Efficiency of NOx Adsorber Catalysts Oxidation State Optimization for Maximum Efficiency of NOx Adsorber Catalysts Presentation given at the 16th...

  20. Engineer End Uses for Maximum Efficiency | Department of Energy

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

    Engineer End Uses for Maximum Efficiency Engineer End Uses for Maximum Efficiency This tip sheet outlines steps to ensure the efficiency of compressed air end-use applications....

  1. Electron energy spectrum and maximum disruption angle under multi...

    Office of Scientific and Technical Information (OSTI)

    Conference: Electron energy spectrum and maximum disruption angle under multi-photon beamstrahlung Citation Details In-Document Search Title: Electron energy spectrum and maximum ...

  2. Theoretical Estimate of Maximum Possible Nuclear Explosion

    DOE R&D Accomplishments [OSTI]

    Bethe, H. A.

    1950-01-31

    The maximum nuclear accident which could occur in a Na-cooled, Be moderated, Pu and power producing reactor is estimated theoretically. (T.R.H.) 2O82 Results of nuclear calculations for a variety of compositions of fast, heterogeneous, sodium-cooled, U-235-fueled, plutonium- and power-producing reactors are reported. Core compositions typical of plate-, pin-, or wire-type fuel elements and with uranium as metal, alloy, and oxide were considered. These compositions included atom ratios in the following range: U-23B to U-235 from 2 to 8; sodium to U-235 from 1.5 to 12; iron to U-235 from 5 to 18; and vanadium to U-235 from 11 to 33. Calculations were performed to determine the effect of lead and iron reflectors between the core and blanket. Both natural and depleted uranium were evaluated as the blanket fertile material. Reactors were compared on a basis of conversion ratio, specific power, and the product of both. The calculated results are in general agreement with the experimental results from fast reactor assemblies. An analysis of the effect of new cross-section values as they became available is included. (auth)

  3. Extended maximum likelihood halo-independent analysis of dark matter direct detection data

    SciTech Connect (OSTI)

    Gelmini, Graciela B.; Georgescu, Andreea; Gondolo, Paolo; Huh, Ji-Haeng

    2015-11-24

    We extend and correct a recently proposed maximum-likelihood halo-independent method to analyze unbinned direct dark matter detection data. Instead of the recoil energy as independent variable we use the minimum speed a dark matter particle must have to impart a given recoil energy to a nucleus. This has the advantage of allowing us to apply the method to any type of target composition and interaction, e.g. with general momentum and velocity dependence, and with elastic or inelastic scattering. We prove the method and provide a rigorous statistical interpretation of the results. As first applications, we find that for dark matter particles with elastic spin-independent interactions and neutron to proton coupling ratio f{sub n}/f{sub p}=−0.7, the WIMP interpretation of the signal observed by CDMS-II-Si is compatible with the constraints imposed by all other experiments with null results. We also find a similar compatibility for exothermic inelastic spin-independent interactions with f{sub n}/f{sub p}=−0.8.

  4. Near-IR spectroscopic monitoring of CLASS I protostars: Variability of accretion and wind indicators

    SciTech Connect (OSTI)

    Connelley, Michael S.; Greene, Thomas P.

    2014-06-01

    We present the results of a program that monitored the near-IR spectroscopic variability of a sample of 19 embedded protostars. Spectra were taken on time intervals from 2 days to 3 yr, over a wavelength range from 0.85 ?m to 2.45 ?m, for 4-9 epochs of observations per target. We found that the spectra of all targets are variable and that every emission feature observed is also variable (although not for all targets). With one exception, there were no drastic changes in the continua of the spectra, nor did any line completely disappear, nor did any line appear that was not previously apparent. This analysis focuses on understanding the connection between accretion (traced by H Br ? and CO) and the wind (traced by He I, [Fe II], and sometimes H{sub 2}). For both accretion and wind tracers, the median variability was constant versus the time interval between observations; however, the maximum variability that we observed increased with the time interval between observations. Extinction is observed to vary within the minimum sampling time of 2 days, suggesting extinguishing material within a few stellar radii at high disk latitudes. The variability of [Fe II] and H{sub 2} were correlated for most (but not all) of the 7 young stellar objects showing both features, and the amplitude of the variability depends on the veiling. Although the occurrence of CO and Br ? emission are connected, their variability is uncorrelated, suggesting that these emissions originate in separate regions near the protostar (e.g., disk and wind). The variability of Br ? and wind tracers were found to be positively correlated, negatively correlated, or uncorrelated, depending on the target. The variability of Br ?, [Fe II], and H{sub 2} always lies on a plane, although the orientation of the plane in three dimensions depends on the target. While we do not understand all interactions behind the variability that we observed, we have shown that spectroscopic variability is a powerful tool toward understanding the star formation process.

  5. Property:Maximum Velocity(m/s) | Open Energy Information

    Open Energy Info (EERE)

    Velocity(ms) Jump to: navigation, search Property Name Maximum Velocity(ms) Property Type String Pages using the property "Maximum Velocity(ms)" Showing 25 pages using this...

  6. Property:Maximum Wave Length(m) | Open Energy Information

    Open Energy Info (EERE)

    Length(m) Jump to: navigation, search Property Name Maximum Wave Length(m) Property Type String Pages using the property "Maximum Wave Length(m)" Showing 18 pages using this...

  7. Property:Maximum Wave Height(m) | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Property Name Maximum Wave Height(m) Property Type String Pages using the property "Maximum Wave Height(m)" Showing 25 pages using this property....

  8. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by

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

    AERMOD-PRIME | Department of Energy PRIME Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Compliance based on highest, second-highest, short-term, and highest annual concentrations. PDF icon Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME

  9. The Taiwanese-American occultation survey project stellar variability. III. Detection of 58 new variable stars

    SciTech Connect (OSTI)

    Ishioka, R.; Wang, S.-Y.; Zhang, Z.-W.; Lehner, M. J.; Cook, K. H.; King, S.-K.; Lee, T.; Marshall, S. L.; Schwamb, M. E.; Wang, J.-H.; Wen, C.-Y.; Alcock, C.; Protopapas, P.; Axelrod, T.; Bianco, F. B.; Byun, Y.-I.; Chen, W. P.; Ngeow, C.-C.; Kim, D.-W.; Rice, J. A.

    2014-04-01

    The Taiwanese-American Occultation Survey project is designed for the detection of stellar occultations by small-size Kuiper Belt Objects, and it has monitored selected fields along the ecliptic plane by using four telescopes with a 3 deg{sup 2} field of view on the sky since 2005. We have analyzed data accumulated during 2005-2012 to detect variable stars. Sixteen fields with observations of more than 100 epochs were examined. We recovered 85 variables among a total of 158 known variable stars in these 16 fields. Most of the unrecovered variables are located in the fields observed less frequently. We also detected 58 variable stars which are not listed in the International Variable Star Index of the American Association of Variable Star Observers. These variable stars are classified as 3 RR Lyrae, 4 Cepheid, 1 ? Scuti, 5 Mira, 15 semi-regular, and 27 eclipsing binaries based on the periodicity and the profile of the light curves.

  10. Boiler Maximum Achievable Control Technology (MACT) Technical Assistance -

    Office of Environmental Management (EM)

    Fact Sheet, April 2015 | Department of Energy Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact Sheet, April 2015 Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact Sheet, April 2015 This fact sheet about AMO's Boiler Maximum Achievable Control Technology (Boiler MACT) Technical Assistance Program was last updated in April 2015. PDF icon Boiler_MACT_factsheet.pdf More Documents & Publications CHP: A Technical & Economic

  11. Montana Total Maximum Daily Load Development Projects Wiki |...

    Open Energy Info (EERE)

    Wiki Jump to: navigation, search OpenEI Reference LibraryAdd to library Web Site: Montana Total Maximum Daily Load Development Projects Wiki Abstract Provides information on...

  12. Maximum Likelihood Analysis of Low Energy CDMS II Germanium Data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Agnese, R.

    2015-03-30

    We report on the results of a search for a Weakly Interacting Massive Particle (WIMP) signal in low-energy data of the Cryogenic Dark Matter Search experiment using a maximum likelihood analysis. A background model is constructed using GEANT4 to simulate the surface-event background from Pb210decay-chain events, while using independent calibration data to model the gamma background. Fitting this background model to the data results in no statistically significant WIMP component. In addition, we also perform fits using an analytic ad hoc background model proposed by Collar and Fields, who claimed to find a large excess of signal-like events in ourmore » data. Finally, we confirm the strong preference for a signal hypothesis in their analysis under these assumptions, but excesses are observed in both single- and multiple-scatter events, which implies the signal is not caused by WIMPs, but rather reflects the inadequacy of their background model.« less

  13. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by

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

    AERMOD-PRIME, Units 3, 1, 2 SO2 Case | Department of Energy PRIME, Units 3, 1, 2 SO2 Case Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 3, 1, 2 SO2 Case Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 3, 1, 2 SO2 Case. Compliance based on highest, second-highest, short-term, and highest annual concentrations. PDF icon Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by

  14. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by

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

    AERMOD-PRIME, Units 4, 1, 2 SO2 Case | Department of Energy 4, 1, 2 SO2 Case Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 4, 1, 2 SO2 Case Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 4, 1, 2 SO2 Case. Compliance based on highest, second-highest, short-term, and highest annual concentrations. PDF icon Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units

  15. Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by

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

    AERMOD-PRIME, Units 5, 1, 2 SO2 Case | Department of Energy 5, 1, 2 SO2 Case Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 5, 1, 2 SO2 Case Docket No. EO-05-01: Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units 5, 1, 2 SO2 Case. Compliance based on highest, second-highest, short-term, and highest annual concentrations. PDF icon Mirant Potomac, Alexandria, Virginia: Maximum Impacts Predicted by AERMOD-PRIME, Units

  16. Maximum Photovoltaic Penetration Levels on Typical Distribution Feeders: Preprint

    SciTech Connect (OSTI)

    Hoke, A.; Butler, R.; Hambrick, J.; Kroposki, B.

    2012-07-01

    This paper presents simulation results for a taxonomy of typical distribution feeders with various levels of photovoltaic (PV) penetration. For each of the 16 feeders simulated, the maximum PV penetration that did not result in steady-state voltage or current violation is presented for several PV location scenarios: clustered near the feeder source, clustered near the midpoint of the feeder, clustered near the end of the feeder, randomly located, and evenly distributed. In addition, the maximum level of PV is presented for single, large PV systems at each location. Maximum PV penetration was determined by requiring that feeder voltages stay within ANSI Range A and that feeder currents stay within the ranges determined by overcurrent protection devices. Simulations were run in GridLAB-D using hourly time steps over a year with randomized load profiles based on utility data and typical meteorological year weather data. For 86% of the cases simulated, maximum PV penetration was at least 30% of peak load.

  17. Alaska Maximum Number of Active Crews Engaged in Seismic Surveying...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Seismic Surveying (Number of Elements) Alaska Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec...

  18. Oxidation State Optimization for Maximum Efficiency of NOx Adsorber

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

    Catalysts | Department of Energy State Optimization for Maximum Efficiency of NOx Adsorber Catalysts Oxidation State Optimization for Maximum Efficiency of NOx Adsorber Catalysts Presentation given at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. PDF icon deer10_li.pdf More Documents & Publications Lean NOx Trap Regeneration Selectivity Towards N2O -- Similarities and Differences Between H2, CO and C3H6 Reductants

  19. CABLE TECHNOLOGY LABORATORIES, INC. DETERMINATION OF THRESHOLD AND MAXIMUM

    Office of Scientific and Technical Information (OSTI)

    CABLE TECHNOLOGY LABORATORIES, INC. DETERMINATION OF THRESHOLD AND MAXIMUM OPERATING ELECTRIC STRESSES FOR SELECTED HIGH VOLTAGE INSULATIONS Investigation of Aged Polymeric Dielectric Cable DOE CONTRACT DE-AC 02-80RA 50156 Final Report Prepared by : Approved by: G.S. Eager, Jr. G.W. Seman B. Fryszczyn C. Katz November 1995 690 Jersey Avenue - RO. Box 707 - Fax: (908) 846-5531 New Brunswick, N.J. 08903 Tel: (908) 8463133 DETERMINATION OF THRESHOLD AND MAXIMUM OPERATING ELECTRIC STRESSES FOR

  20. Are There Practical Approaches for Achieving the Theoretical Maximum Engine

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

    Efficiency? | Department of Energy Are There Practical Approaches for Achieving the Theoretical Maximum Engine Efficiency? Are There Practical Approaches for Achieving the Theoretical Maximum Engine Efficiency? 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: University of Wisconsin, Madison PDF icon 2004_deer_foster.pdf More Documents & Publications Fuel Modification t Facilitate Future Combustion Regimes? The Next ICE Age The Next ICE Age

  1. Table 10.1 Nonswitchable Minimum and Maximum Consumption, 2002

    U.S. Energy Information Administration (EIA) Indexed Site

    Nonswitchable Minimum and Maximum Consumption, 2002; " " Level: National and Regional Data;" " Row: Energy Sources;" " Column: Consumption Potential;" " Unit: Physical Units." ,,,,"RSE" ,"Actual","Minimum","Maximum","Row" "Energy Sources","Consumption","Consumption(a)","Consumption(b)","Factors" ,"Total United States" "RSE Column

  2. VARIABLE TIME DELAY MEANS

    DOE Patents [OSTI]

    Clemensen, R.E.

    1959-11-01

    An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

  3. Variable Frequency Drives

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

    Marketing Toolkit The Benefits of Variable Frequency Drives (VFDs) VFDs help adjust motor speeds to match loads and improve efficiency while conserving energy. The benefits...

  4. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  5. Understanding Biomass Feedstock Variability

    SciTech Connect (OSTI)

    Kevin L. Kenney; Garold L. Gresham; William A. Smith; Tyler L. Westover

    2013-01-01

    If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per-ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that, due to inherent species variabilities, production conditions and differing harvest, collection and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

  6. Maximum patch method for directional dark matter detection

    SciTech Connect (OSTI)

    Henderson, Shawn; Monroe, Jocelyn; Fisher, Peter [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Laboratory for Nuclear Science, MIT Kavli Institute for Astrophysics and Space Research, Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2008-07-01

    Present and planned dark matter detection experiments search for WIMP-induced nuclear recoils in poorly known background conditions. In this environment, the maximum gap statistical method provides a way of setting more sensitive cross section upper limits by incorporating known signal information. We give a recipe for the numerical calculation of upper limits for planned directional dark matter detection experiments, that will measure both recoil energy and angle, based on the gaps between events in two-dimensional phase space.

  7. Maximum Entry and Mandatory Separation Ages for Certain Security Employees

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-10-11

    The policy establishes the DOE policy on maximum entry and mandatory separation ages for primary or secondary positions covered under special statutory retirement provisions and for those employees whose primary duties are the protection of officials of the United States against threats to personal safety or the investigation, apprehension, and detention of individuals suspected or convicted of offenses against the criminal laws of the United States. Admin Chg 1, dated 12-1-11, supersedes DOE P 310.1.

  8. State observer for synchronous motors

    DOE Patents [OSTI]

    Lang, Jeffrey H. (Waltham, MA)

    1994-03-22

    A state observer driven by measurements of phase voltages and currents for estimating the angular orientation of a rotor of a synchronous motor such as a variable reluctance motor (VRM). Phase voltages and currents are detected and serve as inputs to a state observer. The state observer includes a mathematical model of the electromechanical operation of the synchronous motor. The characteristics of the state observer are selected so that the observer estimates converge to the actual rotor angular orientation and velocity, winding phase flux linkages or currents.

  9. Maximum U.S. Active Seismic Crew Counts

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

    Jurisdiction waters of the Gulf of Mexico. Alaska is all onshore. Total crews includes crews with unknown survey dimension. Data are reported on the first and fifteenth of each month, except January when they are reported only on the fifteenth. When semi-monthly values differ for the month, the larger of the two values is shown here. Consequently, this table reflects the maximum number of crews at work at any time during the month. See Definitions, Sources, and Notes link above for more

  10. Analysis to determine the maximum dimensions of flexible apertures in sensored security netting products.

    SciTech Connect (OSTI)

    Murton, Mark; Bouchier, Francis A.; vanDongen, Dale T.; Mack, Thomas Kimball; Cutler, Robert Paul; Ross, Michael P.

    2013-08-01

    Although technological advances provide new capabilities to increase the robustness of security systems, they also potentially introduce new vulnerabilities. New capability sometimes requires new performance requirements. This paper outlines an approach to establishing a key performance requirement for an emerging intrusion detection sensor: the sensored net. Throughout the security industry, the commonly adopted standard for maximum opening size through barriers is a requirement based on square inches-typically 96 square inches. Unlike standard rigid opening, the dimensions of a flexible aperture are not fixed, but variable and conformable. It is demonstrably simple for a human intruder to move through a 96-square-inch opening that is conformable to the human body. The longstanding 96-square-inch requirement itself, though firmly embedded in policy and best practice, lacks a documented empirical basis. This analysis concluded that the traditional 96-square-inch standard for openings is insufficient for flexible openings that are conformable to the human body. Instead, a circumference standard is recommended for these newer types of sensored barriers. The recommended maximum circumference for a flexible opening should be no more than 26 inches, as measured on the inside of the netting material.

  11. Possible dynamical explanations for Paltridge's principle of maximum entropy production

    SciTech Connect (OSTI)

    Virgo, Nathaniel Ikegami, Takashi

    2014-12-05

    Throughout the history of non-equilibrium thermodynamics a number of theories have been proposed in which complex, far from equilibrium flow systems are hypothesised to reach a steady state that maximises some quantity. Perhaps the most celebrated is Paltridge's principle of maximum entropy production for the horizontal heat flux in Earth's atmosphere, for which there is some empirical support. There have been a number of attempts to derive such a principle from maximum entropy considerations. However, we currently lack a more mechanistic explanation of how any particular system might self-organise into a state that maximises some quantity. This is in contrast to equilibrium thermodynamics, in which models such as the Ising model have been a great help in understanding the relationship between the predictions of MaxEnt and the dynamics of physical systems. In this paper we show that, unlike in the equilibrium case, Paltridge-type maximisation in non-equilibrium systems cannot be achieved by a simple dynamical feedback mechanism. Nevertheless, we propose several possible mechanisms by which maximisation could occur. Showing that these occur in any real system is a task for future work. The possibilities presented here may not be the only ones. We hope that by presenting them we can provoke further discussion about the possible dynamical mechanisms behind extremum principles for non-equilibrium systems, and their relationship to predictions obtained through MaxEnt.

  12. Variable capacity gasification burner

    SciTech Connect (OSTI)

    Saxon, D.I.

    1985-03-05

    A variable capacity burner that may be used in gasification processes, the burner being adjustable when operating in its intended operating environment to operate at two different flow capacities, with the adjustable parts being dynamically sealed within a statically sealed structural arrangement to prevent dangerous blow-outs of the reactants to the atmosphere.

  13. Variable thrust cartridge

    DOE Patents [OSTI]

    Taleyarkhan, Rusi P. (Knoxville, TN)

    2000-11-07

    The present invention is a variable thrust cartridge comprising a water-molten aluminum reaction chamber from which a slug is propelled. The cartridge comprises a firing system that initiates a controlled explosion from the reaction chamber. The explosive force provides a thrust to a slug, preferably contained within the cartridge.

  14. Conductivity maximum in a charged colloidal suspension (Journal...

    Office of Scientific and Technical Information (OSTI)

    effects: colloid effective charge saturation due to counterion 'condensation' and diffusion slowdown due to the relaxation effect. In agreement with previous observations, we...

  15. Reduction in maximum time uncertainty of paired time signals

    DOE Patents [OSTI]

    Theodosiou, G.E.; Dawson, J.W.

    1981-02-11

    Reduction in the maximum time uncertainty (t/sub max/ - t/sub min/) of a series of paired time signals t/sub 1/ and t/sub 2/ varying between two input terminals and representative of a series of single events where t/sub 1/ less than or equal to t/sub 2/ and t/sub 1/ + t/sub 2/ equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t/sub min/) of the first signal t/sub 1/ closer to t/sub max/ and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20 to 800.

  16. Total Estimated Contract Cost: Contract Option Period: Maximum Fee

    Office of Environmental Management (EM)

    Maximum Fee Performance Period Fee Earned FY2011/2012 $4,059,840 FY2013 $2,928,000 FY2014 $3,022,789 FY2015 FY2016 Cumulative Fee $10,010,629 $19,878,019 $3,214,544 $5,254,840 $5,662,028 $1,421,695 Fee Available $4,324,912 $417,833,183 Contract Base Period: January 3, 2011 - September 2, 2016 (Extended) Fee Information Minimum Fee $0 N/A $19,878,019 Contractor: Babcock & Wilcox Conversion Services, LLC Contract Number: DE-AC30-11CC40015 Contract Type: Cost Plus Award Fee EM Contractor Fee

  17. Reduction in maximum time uncertainty of paired time signals

    DOE Patents [OSTI]

    Theodosiou, G.E.; Dawson, J.W.

    1983-10-04

    Reduction in the maximum time uncertainty (t[sub max]--t[sub min]) of a series of paired time signals t[sub 1] and t[sub 2] varying between two input terminals and representative of a series of single events where t[sub 1][<=]t[sub 2] and t[sub 1]+t[sub 2] equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t[sub min]) of the first signal t[sub 1] closer to t[sub max] and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20--800. 6 figs.

  18. Reduction in maximum time uncertainty of paired time signals

    DOE Patents [OSTI]

    Theodosiou, George E. (West Chicago, IL); Dawson, John W. (Clarendon Hills, IL)

    1983-01-01

    Reduction in the maximum time uncertainty (t.sub.max -t.sub.min) of a series of paired time signals t.sub.1 and t.sub.2 varying between two input terminals and representative of a series of single events where t.sub.1 .ltoreq.t.sub.2 and t.sub.1 +t.sub.2 equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t.sub.min) of the first signal t.sub.1 closer to t.sub.max and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20-800.

  19. Property:Maximum Velocity with Constriction(m/s) | Open Energy...

    Open Energy Info (EERE)

    Velocity with Constriction(ms) Jump to: navigation, search Property Name Maximum Velocity with Constriction(ms) Property Type String Pages using the property "Maximum Velocity...

  20. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  1. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  2. Variable laser attenuator

    DOE Patents [OSTI]

    Foltyn, S.R.

    1987-05-29

    The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

  3. Estimate of Maximum Underground Working Gas Storage Capacity in the United States

    Reports and Publications (EIA)

    2006-01-01

    This report examines the aggregate maximum capacity for U.S. natural gas storage. Although the concept of maximum capacity seems quite straightforward, there are numerous issues that preclude the determination of a definitive maximum volume. The report presents three alternative estimates for maximum capacity, indicating appropriate caveats for each.

  4. LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL

    SciTech Connect (OSTI)

    Don Augenstein

    2001-02-01

    The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.

  5. Weakest solar wind of the space age and the current 'MINI' solar maximum

    SciTech Connect (OSTI)

    McComas, D. J.; Angold, N.; Elliott, H. A.; Livadiotis, G.; Schwadron, N. A.; Smith, C. W.; Skoug, R. M.

    2013-12-10

    The last solar minimum, which extended into 2009, was especially deep and prolonged. Since then, sunspot activity has gone through a very small peak while the heliospheric current sheet achieved large tilt angles similar to prior solar maxima. The solar wind fluid properties and interplanetary magnetic field (IMF) have declined through the prolonged solar minimum and continued to be low through the current mini solar maximum. Compared to values typically observed from the mid-1970s through the mid-1990s, the following proton parameters are lower on average from 2009 through day 79 of 2013: solar wind speed and beta (?11%), temperature (?40%), thermal pressure (?55%), mass flux (?34%), momentum flux or dynamic pressure (?41%), energy flux (?48%), IMF magnitude (?31%), and radial component of the IMF (?38%). These results have important implications for the solar wind's interaction with planetary magnetospheres and the heliosphere's interaction with the local interstellar medium, with the proton dynamic pressure remaining near the lowest values observed in the space age: ?1.4 nPa, compared to ?2.4 nPa typically observed from the mid-1970s through the mid-1990s. The combination of lower magnetic flux emergence from the Sun (carried out in the solar wind as the IMF) and associated low power in the solar wind points to the causal relationship between them. Our results indicate that the low solar wind output is driven by an internal trend in the Sun that is longer than the ?11 yr solar cycle, and they suggest that this current weak solar maximum is driven by the same trend.

  6. Device for adapting continuously variable transmissions to infinitely variable transmissions with forward-neutral-reverse capabilities

    DOE Patents [OSTI]

    Wilkes, Donald F. (Albuquerque, NM); Purvis, James W. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM)

    1997-01-01

    An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.

  7. LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL

    SciTech Connect (OSTI)

    Don Augenstein; Ramin Yazdani; Rick Moore; Michelle Byars; Jeff Kieffer; Professor Morton Barlaz; Rinav Mehta

    2000-02-26

    Controlled landfilling is an approach to manage solid waste landfills, so as to rapidly complete methane generation, while maximizing gas capture and minimizing the usual emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated to more rapid and earlier completion to full potential by improving conditions (principally moisture, but also temperature) to optimize biological processes occurring within the landfill. Gas is contained through use of surface membrane cover. Gas is captured via porous layers, under the cover, operated at slight vacuum. A field demonstration project has been ongoing under NETL sponsorship for the past several years near Davis, CA. Results have been extremely encouraging. Two major benefits of the technology are reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times, more predictably, than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role both in reduction of US greenhouse gas emissions and in US renewable energy. The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.

  8. Estimates of maximum strains induced in buried pipelines by dynamic loading

    SciTech Connect (OSTI)

    Fernandez, G.; Al-Chaar, G.; Brady, P.

    1995-12-31

    An evaluation of pipe strains measured during full scale blast in-situ tests was carried out to assess the effects produced by a nearby quarry blast in a buried, steel pipeline carrying pressurized gas. The result of the blast tests indicated that the magnitude of the maximum circumferential strain is equal or larger than the magnitude of the maximum axial strain measured in the pipe. It was also observed that circumferential strains can develop simultaneously with the dynamic-induced axial strains, resulting in a more critical loading condition than the one contemplated by the ASCE (1983) design guidelines for seismic loading. This behavior can become critical in pressurized pipes where significant circumferential stresses are already present under normal operating conditions. Based on the results of these tests, recommendations for including circumferential strains are suggested to the ASCE (1983) Design Guidelines. Consideration should be given to a compressive wave traveling at a high angle which respect to the longitudinal axis of the pipe which can induce squeezing or ovaling of the pipe section, resulting in significant circumferential strains in the pipe.

  9. Simulation of the intraseasonal variability over the Eastern Pacific ITCZ

    Office of Scientific and Technical Information (OSTI)

    in climate models (Journal Article) | SciTech Connect Simulation of the intraseasonal variability over the Eastern Pacific ITCZ in climate models Citation Details In-Document Search Title: Simulation of the intraseasonal variability over the Eastern Pacific ITCZ in climate models During boreal summer, convective activity over the eastern Pacific (EPAC) inter-tropical convergence zone (ITCZ) exhibits vigorous intraseasonal variability (ISV). Previous observational studies identified two

  10. A 3D approximate maximum likelihood solver for localization of fish implanted with acoustic transmitters

    SciTech Connect (OSTI)

    Li, Xinya; Deng, Z. Daniel; USA, Richland Washington; Sun, Yannan; USA, Richland Washington; Martinez, Jayson J.; USA, Richland Washington; Fu, Tao; USA, Richland Washington; McMichael, Geoffrey A.; USA, Richland Washington; Carlson, Thomas J.; USA, Richland Washington

    2014-11-27

    Better understanding of fish behavior is vital for recovery of many endangered species including salmon. The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed to observe the out-migratory behavior of juvenile salmonids tagged by surgical implantation of acoustic micro-transmitters and to estimate the survival when passing through dams on the Snake and Columbia Rivers. A robust three-dimensional solver was needed to accurately and efficiently estimate the time sequence of locations of fish tagged with JSATS acoustic transmitters, to describe in sufficient detail the information needed to assess the function of dam-passage design alternatives. An approximate maximum likelihood solver was developed using measurements of time difference of arrival from all hydrophones in receiving arrays on which a transmission was detected. Field experiments demonstrated that the developed solver performed significantly better in tracking efficiency and accuracy than other solvers described in the literature.

  11. A 3D approximate maximum likelihood solver for localization of fish implanted with acoustic transmitters

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Xinya; Deng, Z. Daniel; USA, Richland Washington; Sun, Yannan; USA, Richland Washington; Martinez, Jayson J.; USA, Richland Washington; Fu, Tao; USA, Richland Washington; McMichael, Geoffrey A.; et al

    2014-11-27

    Better understanding of fish behavior is vital for recovery of many endangered species including salmon. The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed to observe the out-migratory behavior of juvenile salmonids tagged by surgical implantation of acoustic micro-transmitters and to estimate the survival when passing through dams on the Snake and Columbia Rivers. A robust three-dimensional solver was needed to accurately and efficiently estimate the time sequence of locations of fish tagged with JSATS acoustic transmitters, to describe in sufficient detail the information needed to assess the function of dam-passage design alternatives. An approximate maximum likelihood solver was developedmore » using measurements of time difference of arrival from all hydrophones in receiving arrays on which a transmission was detected. Field experiments demonstrated that the developed solver performed significantly better in tracking efficiency and accuracy than other solvers described in the literature.« less

  12. Property:Maximum Wave Height(m) at Wave Period(s) | Open Energy...

    Open Energy Info (EERE)

    at Wave Period(s) Jump to: navigation, search Property Name Maximum Wave Height(m) at Wave Period(s) Property Type String Pages using the property "Maximum Wave Height(m) at Wave...

  13. U.S. Lower 48 States Onshore Maximum Number of Active Crews Engaged...

    Gasoline and Diesel Fuel Update (EIA)

    Onshore Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) U.S. Lower 48 States Onshore Maximum Number of Active Crews Engaged in Seismic Surveying...

  14. U.S. Maximum Number of Active Crews Engaged in Seismic Surveying...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) U.S. Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) Year Jan Feb...

  15. U.S. Lower 48 States Offshore Maximum Number of Active Crews...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Offshore Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) U.S. Lower 48 States Offshore Maximum Number of Active Crews Engaged in Seismic Surveying...

  16. Application Performance Variability on Hopper

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

    Application Performance Variability on Hopper Application Performance Variability on Hopper Introduction The Hopper system is a Cray XE6 system with roughly 6300 compute nodes. In normal day to day operations, Hopper can be running hundreds of individual applications at any given time. Some users have reported application runtime variability, in some cases as large as 30-40%. Non-uniform runtimes makes it more difficult for scientists to measure the performance of their codes and to estimate the

  17. VariableR reclustering in multiple top quark events - Oral Presentatio...

    Office of Scientific and Technical Information (OSTI)

    VariableR reclustering in multiple top quark events - Oral Presentation Citation Details In-Document Search Title: VariableR reclustering in multiple top quark events - Oral...

  18. Sweetspot: Near-infrared observations of 13 type Ia supernovae...

    Office of Scientific and Technical Information (OSTI)

    With only one to three points per light curve and a prior on the time of maximum from the ... These observations continue to demonstrate the improved standard brightness of SNe Ia in ...

  19. Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV

    SciTech Connect (OSTI)

    Abraham, J.; Abreu, P.; Aglietta, M.; Ahn, E.J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; Andringa, S.; /Lisbon, IST /Boskovic Inst., Zagreb

    2010-02-01

    We describe the measurement of the depth of maximum, X{sub max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10{sup 18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{sub -21}{sup +35}) g/cm{sup 2}/decade below 10{sup 18.24 {+-} 0.05}eV, and (24 {+-} 3) g/cm{sup 2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{sup 2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

  20. Electron energy spectrum and maximum disruption angle under multi-photon

    Office of Scientific and Technical Information (OSTI)

    beamstrahlung (Conference) | SciTech Connect Electron energy spectrum and maximum disruption angle under multi-photon beamstrahlung Citation Details In-Document Search Title: Electron energy spectrum and maximum disruption angle under multi-photon beamstrahlung The final electron energy spectrum under multi-photon beamstrahlung process is derived analytically in the classical and the intermediate regimes. The maximum disruption angle from the low energy tail of the spectrum is also

  1. EERE Takes Important Steps to Ensure Maximum Impact of Technology Program

    Office of Environmental Management (EM)

    Investments | Department of Energy Takes Important Steps to Ensure Maximum Impact of Technology Program Investments EERE Takes Important Steps to Ensure Maximum Impact of Technology Program Investments November 20, 2014 - 6:06pm Addthis Tracking impact of EERE’s investments in wind, solar and other programs is essential to achieve maximum return for taxpayer investment. | Photos courtesy of the National Renewable Energy Laboratory Tracking impact of EERE's investments in wind, solar and

  2. Maximum allowable hydraulic ram force for heel jet removal Tank 241-C-106

    SciTech Connect (OSTI)

    PAULSEN, S.S.

    2003-01-10

    This document contains an evaluation of the maximum force that can be used to actuate the hydraulic ram assembly without causing permanent damage to the riser or pit.

  3. TabVar: Tabulated Variables

    Energy Science and Technology Software Center (OSTI)

    2015-12-15

    TabVar: A Python library for manipulating datasets in the form of tabulated variables. Tables in tabvar contain many columns representing independent variables, but exactly one distinguished column for the dependent variable. Having a single distinguished column allows a natural lifting of arithmetic operators to tables, much (and in fact fully generalizing) multidimensional array arithmetic. The convenient syntax of whole-table arithmetic, along with the usual operations of filtering and aggregation, and all in the setting ofmore » python's interactive REPL allows for rapid exploration of datasets.« less

  4. Variable focal length deformable mirror

    DOE Patents [OSTI]

    Headley, Daniel (Albuquerque, NM); Ramsey, Marc (Albuquerque, NM); Schwarz, Jens (Albuquerque, NM)

    2007-06-12

    A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

  5. Setting the Renormalization Scale in QCD: The Principle of Maximum Conformality

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; Di Giustino, Leonardo; /SLAC

    2011-08-19

    A key problem in making precise perturbative QCD predictions is the uncertainty in determining the renormalization scale {mu} of the running coupling {alpha}{sub s}({mu}{sup 2}): The purpose of the running coupling in any gauge theory is to sum all terms involving the {beta} function; in fact, when the renormalization scale is set properly, all non-conformal {beta} {ne} 0 terms in a perturbative expansion arising from renormalization are summed into the running coupling. The remaining terms in the perturbative series are then identical to that of a conformal theory; i.e., the corresponding theory with {beta} = 0. The resulting scale-fixed predictions using the 'principle of maximum conformality' (PMC) are independent of the choice of renormalization scheme - a key requirement of renormalization group invariance. The results avoid renormalon resummation and agree with QED scale-setting in the Abelian limit. The PMC is also the theoretical principle underlying the BLM procedure, commensurate scale relations between observables, and the scale-setting method used in lattice gauge theory. The number of active flavors nf in the QCD {beta} function is also correctly determined. We discuss several methods for determining the PMC/BLM scale for QCD processes. We show that a single global PMC scale, valid at leading order, can be derived from basic properties of the perturbative QCD cross section. The elimination of the renormalization scheme ambiguity using the PMC will not only increase the precision of QCD tests, but it will also increase the sensitivity of collider experiments to new physics beyond the Standard Model.

  6. Variable gas leak rate valve

    DOE Patents [OSTI]

    Eernisse, Errol P.; Peterson, Gary D.

    1976-01-01

    A variable gas leak rate valve which utilizes a poled piezoelectric element to control opening and closing of the valve. The gas flow may be around a cylindrical rod with a tubular piezoelectric member encircling the rod for seating thereagainst to block passage of gas and for reopening thereof upon application of suitable electrical fields.

  7. Operating Reserves and Variable Generation

    SciTech Connect (OSTI)

    Ela, E.; Milligan, M.; Kirby, B.

    2011-08-01

    This report tries to first generalize the requirements of the power system as it relates to the needs of operating reserves. It also includes a survey of operating reserves and how they are managed internationally in system operations today and then how new studies and research are proposing they may be managed in the future with higher penetrations of variable generation.

  8. Title 43 CFR 3206.12 What are the Minimum and Maximum Lease Sizes...

    Open Energy Info (EERE)

    .12 What are the Minimum and Maximum Lease Sizes? Jump to: navigation, search OpenEI Reference LibraryAdd to library Legal Document- Federal RegulationFederal Regulation: Title 43...

  9. U.S. Lower 48 States Offshore Maximum Number of Active Crews...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Offshore Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 167...

  10. U.S. Lower 48 States Onshore Maximum Number of Active Crews Engaged...

    Gasoline and Diesel Fuel Update (EIA)

    Onshore Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 435 512...

  11. U.S. Maximum Number of Active Crews Engaged in Seismic Surveying...

    Gasoline and Diesel Fuel Update (EIA)

    Maximum Number of Active Crews Engaged in Seismic Surveying (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 615 717 624 481...

  12. A Requirement for Significant Reduction in the Maximum BTU Input Rate of

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

    Decorative Vented Gas Fireplaces Would Impose Substantial Burdens on Manufacturers | Department of Energy A Requirement for Significant Reduction in the Maximum BTU Input Rate of Decorative Vented Gas Fireplaces Would Impose Substantial Burdens on Manufacturers A Requirement for Significant Reduction in the Maximum BTU Input Rate of Decorative Vented Gas Fireplaces Would Impose Substantial Burdens on Manufacturers Comment that a requirement to reduce the BTU input rate of existing decorative

  13. Heterogeneity-corrected vs -uncorrected critical structure maximum point doses in breast balloon brachytherapy

    SciTech Connect (OSTI)

    Kim, Leonard; Narra, Venkat; Yue, Ning

    2013-07-01

    Recent studies have reported potentially clinically meaningful dose differences when heterogeneity correction is used in breast balloon brachytherapy. In this study, we report on the relationship between heterogeneity-corrected and -uncorrected doses for 2 commonly used plan evaluation metrics: maximum point dose to skin surface and maximum point dose to ribs. Maximum point doses to skin surface and ribs were calculated using TG-43 and Varian Acuros for 20 patients treated with breast balloon brachytherapy. The results were plotted against each other and fit with a zero-intercept line. Max skin dose (Acuros) = max skin dose (TG-43) ? 0.930 (R{sup 2} = 0.995). The average magnitude of difference from this relationship was 1.1% (max 2.8%). Max rib dose (Acuros) = max rib dose (TG-43) ? 0.955 (R{sup 2} = 0.9995). The average magnitude of difference from this relationship was 0.7% (max 1.6%). Heterogeneity-corrected maximum point doses to the skin surface and ribs were proportional to TG-43-calculated doses. The average deviation from proportionality was 1%. The proportional relationship suggests that a different metric other than maximum point dose may be needed to obtain a clinical advantage from heterogeneity correction. Alternatively, if maximum point dose continues to be used in recommended limits while incorporating heterogeneity correction, institutions without this capability may be able to accurately estimate these doses by use of a scaling factor.

  14. OBSERVING CORONAL NANOFLARES IN ACTIVE REGION MOSS

    SciTech Connect (OSTI)

    Testa, Paola; DeLuca, Ed; Golub, Leon; Korreck, Kelly; Weber, Mark; De Pontieu, Bart; Martinez-Sykora, Juan; Title, Alan; Hansteen, Viggo; Cirtain, Jonathan; Winebarger, Amy; Kobayashi, Ken; Kuzin, Sergey; Walsh, Robert; DeForest, Craig

    2013-06-10

    The High-resolution Coronal Imager (Hi-C) has provided Fe XII 193A images of the upper transition region moss at an unprecedented spatial ({approx}0.''3-0.''4) and temporal (5.5 s) resolution. The Hi-C observations show in some moss regions variability on timescales down to {approx}15 s, significantly shorter than the minute-scale variability typically found in previous observations of moss, therefore challenging the conclusion of moss being heated in a mostly steady manner. These rapid variability moss regions are located at the footpoints of bright hot coronal loops observed by the Solar Dynamics Observatory/Atmospheric Imaging Assembly in the 94 A channel, and by the Hinode/X-Ray Telescope. The configuration of these loops is highly dynamic, and suggestive of slipping reconnection. We interpret these events as signatures of heating events associated with reconnection occurring in the overlying hot coronal loops, i.e., coronal nanoflares. We estimate the order of magnitude of the energy in these events to be of at least a few 10{sup 23} erg, also supporting the nanoflare scenario. These Hi-C observations suggest that future observations at comparable high spatial and temporal resolution, with more extensive temperature coverage, are required to determine the exact characteristics of the heating mechanism(s).

  15. Variable frequency microwave heating apparatus

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN); Johnson, Arvid C. (Lake in the Hills, IL); Thigpen, Larry T. (Angier, NC)

    1999-01-01

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  16. Sandia defines solar variability zones

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

    defines solar variability zones - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs

  17. Application of asymptotic expansions for maximum likelihood estimators errors to gravitational waves from binary mergers: The single interferometer case

    SciTech Connect (OSTI)

    Zanolin, M.; Vitale, S.; Makris, N.

    2010-06-15

    In this paper we apply to gravitational waves (GW) from the inspiral phase of binary systems a recently derived frequentist methodology to calculate analytically the error for a maximum likelihood estimate of physical parameters. We use expansions of the covariance and the bias of a maximum likelihood estimate in terms of inverse powers of the signal-to-noise ration (SNR)s where the square root of the first order in the covariance expansion is the Cramer Rao lower bound (CRLB). We evaluate the expansions, for the first time, for GW signals in noises of GW interferometers. The examples are limited to a single, optimally oriented, interferometer. We also compare the error estimates using the first two orders of the expansions with existing numerical Monte Carlo simulations. The first two orders of the covariance allow us to get error predictions closer to what is observed in numerical simulations than the CRLB. The methodology also predicts a necessary SNR to approximate the error with the CRLB and provides new insight on the relationship between waveform properties, SNR, dimension of the parameter space and estimation errors. For example the timing match filtering can achieve the CRLB only if the SNR is larger than the Kurtosis of the gravitational wave spectrum and the necessary SNR is much larger if other physical parameters are also unknown.

  18. Geo-neutrino Observation

    SciTech Connect (OSTI)

    Dye, S. T.; Alderman, M.; Batygov, M.; Learned, J. G.; Matsuno, S.; Mahoney, J. M.; Pakvasa, S.; Rosen, M.; Smith, S.; Varner, G.; McDonough, W. F.

    2009-12-17

    Observations of geo-neutrinos measure radiogenic heat production within the earth, providing information on the thermal history and dynamic processes of the mantle. Two detectors currently observe geo-neutrinos from underground locations. Other detection projects in various stages of development include a deep ocean observatory. This paper presents the current status of geo-neutrino observation and describes the scientific capabilities of the deep ocean observatory, with emphasis on geology and neutrino physics.

  19. Estimating the maximum potential revenue for grid connected electricity storage : arbitrage and regulation.

    SciTech Connect (OSTI)

    Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.

    2012-12-01

    The valuation of an electricity storage device is based on the expected future cash ow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the maximum potential revenue benchmark. We conclude with a sensitivity analysis with respect to key parameters.

  20. Variable area light reflecting assembly

    DOE Patents [OSTI]

    Howard, Thomas C. (Raleigh, NC)

    1986-01-01

    Device for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles.

  1. Variable area light reflecting assembly

    DOE Patents [OSTI]

    Howard, T.C.

    1986-12-23

    Device is described for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles. 9 figs.

  2. Hot Pot Field Observations

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

    Lane, Michael

    2013-06-28

    Map of field observations including depressions, springs, evidence of former springs, travertine terraces and vegetation patterns. Map also contains interpretation of possible spring alignments.

  3. Hot Pot Field Observations

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

    Lane, Michael

    Map of field observations including depressions, springs, evidence of former springs, travertine terraces and vegetation patterns. Map also contains interpretation of possible spring alignments.

  4. Variable Average Absolute Percent Differences

    Gasoline and Diesel Fuel Update (EIA)

    Variable Average Absolute Percent Differences Percent of Projections Over- Estimated Gross Domestic Product Real Gross Domestic Product (Average Cumulative Growth)* (Table 2) 0.9 45.8 Petroleum Imported Refiner Acquisition Cost of Crude Oil (Constant $) (Table 3a) 37.7 17.3 Imported Refiner Acquisition Cost of Crude Oil (Nominal $) (Table 3b) 36.6 18.7 Total Petroleum Consumption (Table 4) 7.9 70.7 Crude Oil Production (Table 5) 8.1 51.1 Petroleum Net Imports (Table 6) 24.7 73.8 Natural Gas

  5. HCCI in a Variable Compression Ratio Engine: Effects of Engine...

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

    in a Variable Compression Ratio Engine: Effects of Engine Variables HCCI in a Variable Compression Ratio Engine: Effects of Engine Variables 2004 Diesel Engine Emissions Reduction ...

  6. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  7. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  8. Variable flexure-based fluid filter

    DOE Patents [OSTI]

    Brown, Steve B.; Colston, Jr., Billy W.; Marshall, Graham; Wolcott, Duane

    2007-03-13

    An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.

  9. On the Stochastic Maximum Principle in Optimal Control of Degenerate Diffusions with Lipschitz Coefficients

    SciTech Connect (OSTI)

    Bahlali, Khaled Djehiche, Boualem Mezerdi, Brahim

    2007-12-15

    We establish a stochastic maximum principle in optimal control of a general class of degenerate diffusion processes with global Lipschitz coefficients, generalizing the existing results on stochastic control of diffusion processes. We use distributional derivatives of the coefficients and the Bouleau Hirsh flow property, in order to define the adjoint process on an extension of the initial probability space.

  10. Variable delivery, fixed displacement pump

    DOE Patents [OSTI]

    Sommars, Mark F. (Sparland, IL)

    2001-01-01

    A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.

  11. Variable ratio regenerative braking device

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1981-12-15

    Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) 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. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

  12. Continuously variable focal length lens

    DOE Patents [OSTI]

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  13. Variable residence time vortex combustor

    DOE Patents [OSTI]

    Melconian, Jerry O.

    1987-01-01

    A variable residence time vortex combustor including a primary combustion chamber for containing a combustion vortex, and a plurality of louvres peripherally disposed about the primary combustion chamber and longitudinally distributed along its primary axis. The louvres are inclined to impel air about the primary combustion chamber to cool its interior surfaces and to impel air inwardly to assist in driving the combustion vortex in a first rotational direction and to feed combustion in the primary combustion chamber. The vortex combustor also includes a second combustion chamber having a secondary zone and a narrowed waist region in the primary combustion chamber interconnecting the output of the primary combustion chamber with the secondary zone for passing only lower density particles and trapping higher density particles in the combustion vortex in the primary combustion chamber for substantial combustion.

  14. Evaluation of Longitudinal Variabler in Relativistic Accelerators

    Energy Science and Technology Software Center (OSTI)

    1995-07-13

    ELVIRA is an encoding of an analytical formula to the calculation of longitudinal dynamics variable evolution during an accelerator ramp.

  15. VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA Citation Details In-Document Search Title: VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the presence of circumstellar gas in the progenitor system prior to the explosion, with significant

  16. Application of Maximum Likelihood Bayesian Model Averaging to Groundwater Flow and Transport at the Hanford Site 300 Area

    SciTech Connect (OSTI)

    Meyer, Philip D.; Ye, Ming; Neuman, Shlomo P.; Rockhold, Mark L.

    2008-06-01

    A methodology to systematically and quantitatively assess model predictive uncertainty was applied to saturated zone uranium transport at the 300 Area of the U.S. Department of Energy Hanford Site in Washington State, USA. The methodology extends Maximum Likelihood Bayesian Model Averaging (MLBMA) to account jointly for uncertainties due to the conceptual-mathematical basis of models, model parameters, and the scenarios to which the models are applied. Conceptual uncertainty was represented by postulating four alternative models of hydrogeology and uranium adsorption. Parameter uncertainties were represented by estimation covariances resulting from the joint calibration of each model to observed heads and uranium concentration. Posterior model probability was dominated by one model. Results demonstrated the role of model complexity and fidelity to observed system behavior in determining model probabilities, as well as the impact of prior information. Two scenarios representing alternative future behavior of the Columbia River adjacent to the site were considered. Predictive simulations carried out with the calibrated models illustrated the computation of model- and scenario-averaged predictions and how results can be displayed to clearly indicate the individual contributions to predictive uncertainty of the model, parameter, and scenario uncertainties. The application demonstrated the practicability of applying a comprehensive uncertainty assessment to large-scale, detailed groundwater flow and transport modelling.

  17. Evaluation of Maximum Radionuclide Groundwater Concentrations for Basement Fill Model. Zion Station Restoration Project

    SciTech Connect (OSTI)

    Sullivan, Terry

    2014-12-02

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant in order to establish a new water treatment plant. There is some residual radioactive particles from the plant which need to be brought down to levels so an individual who receives water from the new treatment plant does not receive a radioactive dose in excess of 25 mrem/y?. The objectives of this report are: (a) To present a simplified conceptual model for release from the buildings with residual subsurface structures that can be used to provide an upper bound on contaminant concentrations in the fill material; (b) Provide maximum water concentrations and the corresponding amount of mass sorbed to the solid fill material that could occur in each building for use in dose assessment calculations; (c) Estimate the maximum concentration in a well located outside of the fill material; and (d) Perform a sensitivity analysis of key parameters.

  18. Three dimensional winds: A maximum cross-correlation application to elastic lidar data

    SciTech Connect (OSTI)

    Buttler, W.T.

    1996-05-01

    Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar (light detection and ranging) data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three-dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain-following winds in the Rio Grande valley.

  19. Enhancement of maximum attainable ion energy in the radiation pressure acceleration regime using a guiding structure

    SciTech Connect (OSTI)

    Bulanov, S. S.; Esarey, E.; Schroeder, C. B.; Bulanov, S. V.; Esirkepov, T. Zh.; Kando, M.; Pegoraro, F.; Leemans, W. P.

    2015-03-13

    Radiation Pressure Acceleration is a highly efficient mechanism of laser driven ion acceleration, with the laser energy almost totally transferrable to the ions in the relativistic regime. There is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. In the case of a tightly focused laser pulses, which are utilized to get the highest intensity, another factor limiting the maximum ion energy comes into play, the transverse expansion of the target. Transverse expansion makes the target transparent for radiation, thus reducing the effectiveness of acceleration. Utilization of an external guiding structure for the accelerating laser pulse may provide a way of compensating for the group velocity and transverse expansion effects.

  20. Direct tests of micro channel plates as the active element of a new shower maximum detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ronzhin, A.; Los, S.; Ramberg, E.; Apresyan, A.; Xie, S.; Spiropulu, M.; Kim, H.

    2015-05-22

    We continue the study of micro channel plates (MCP) as the active element of a shower maximum (SM) detector. We present below test beam results obtained with MCPs detecting directly secondary particles of an electromagnetic shower. The MCP efficiency to shower particles is close to 100%. In conclusion, the time resolution obtained for this new type of the SM detector is at the level of 40 ps.

  1. Hydrodynamic equations for electrons in graphene obtained from the maximum entropy principle

    SciTech Connect (OSTI)

    Barletti, Luigi

    2014-08-15

    The maximum entropy principle is applied to the formal derivation of isothermal, Euler-like equations for semiclassical fermions (electrons and holes) in graphene. After proving general mathematical properties of the equations so obtained, their asymptotic form corresponding to significant physical regimes is investigated. In particular, the diffusive regime, the Maxwell-Boltzmann regime (high temperature), the collimation regime and the degenerate gas limit (vanishing temperature) are considered.

  2. Direct tests of micro channel plates as the active element of a new shower maximum detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ronzhin, A.; Los, S.; Ramberg, E.; Apresyan, A.; Xie, S.; Spiropulu, M.; Kim, H.

    2015-05-22

    We continue the study of micro channel plates (MCP) as the active element of a shower maximum (SM) detector. We present below test beam results obtained with MCPs detecting directly secondary particles of an electromagnetic shower. The MCP efficiency to shower particles is close to 100%. Furthermore, the time resolution obtained for this new type of the SM detector is at the level of 40 ps.

  3. Variable path length spectrophotometric probe

    DOE Patents [OSTI]

    O'Rourke, Patrick E. (157 Greenwood Dr., Martiney, GA 30907); McCarty, Jerry E. (104 Recreation Dr., Aiken, SC 29803); Haggard, Ricky A. (1144 Thornwood Drive, North Augusta, SC 29891)

    1992-01-01

    A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.

  4. Deconvolving X-ray spectral variability components in the Seyfert 1.5 NGC 3227

    SciTech Connect (OSTI)

    Arvalo, P.; Markowitz, A.

    2014-03-10

    We present the variability analysis of a 100 ks XMM-Newton observation of the Seyfert 1.5 active galaxy, NGC 3227. The observation found NGC 3227 in a period where its hard power-law component displayed remarkably little long-term variability. This lucky event allows us to clearly observe a soft spectral component undergoing a large-amplitude but slow flux variation. Using combined spectral and timing analysis, we isolate two independent variable continuum components and characterize their behavior as a function of timescale. Rapid and coherent variations throughout the 0.2-10 keV band reveal a spectrally hard (photon index ? ? 1.7-1.8) power law, dominating the observed variability on timescales of 30 ks and shorter. Another component produces coherent fluctuations in the 0.2-2 keV range and is much softer (? ? 3); it dominates the observed variability on timescales greater than 30 ks. Both components are viewed through the same absorbers identified in the time-averaged spectrum. The combined spectral and timing analysis breaks the degeneracy between models for the soft excess: it is consistent with a power-law or thermal Comptonized component but not with a blackbody or an ionized reflection component. We demonstrate that the rapid variability in NGC 3227 is intrinsic to continuum-emitting components and is not an effect of variable absorption.

  5. IMPROVED VARIABLE STAR SEARCH IN LARGE PHOTOMETRIC DATA SETS: NEW VARIABLES IN CoRoT FIELD LRa02 DETECTED BY BEST II

    SciTech Connect (OSTI)

    Fruth, T.; Cabrera, J.; Csizmadia, Sz.; Eigmueller, P.; Erikson, A.; Kirste, S.; Pasternacki, T.; Rauer, H.; Titz-Weider, R.; Kabath, P.; Chini, R.; Lemke, R.; Murphy, M.

    2012-06-15

    The CoRoT field LRa02 has been observed with the Berlin Exoplanet Search Telescope II (BEST II) during the southern summer 2007/2008. A first analysis of stellar variability led to the publication of 345 newly discovered variable stars. Now, a deeper analysis of this data set was used to optimize the variability search procedure. Several methods and parameters have been tested in order to improve the selection process compared to the widely used J index for variability ranking. This paper describes an empirical approach to treat systematic trends in photometric data based upon the analysis of variance statistics that can significantly decrease the rate of false detections. Finally, the process of reanalysis and method improvement has virtually doubled the number of variable stars compared to the first analysis by Kabath et al. A supplementary catalog of 272 previously unknown periodic variables plus 52 stars with suspected variability is presented. Improved ephemerides are given for 19 known variables in the field. In addition, the BEST II results are compared with CoRoT data and its automatic variability classification.

  6. Safety Observations Achieve Results

    Energy Science and Technology Software Center (OSTI)

    2000-01-16

    The SOAR web application provides a multi-checklist capability where focused observations can be created to address risk-likely work environments, tasks, etc. The SOAR web application has numerous reports to sort the data by key word, multiple factors (i.e., location, team, behavior, checklist, work environment, etc.), and the highest frequency of behaviors and error-likely predecessors, etc. Other performance indicators are also provided.

  7. Earth System Observations

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

    4 Earth System Observations Research comprises Earth, ocean, and atmospheric sciences to better understand and predict climate change's impact on ecosystems and to study subsurface geological materials and their interactions. Deploying research facilities globally Forecasting forests' responses to climate change Monitoring terrestrial ecosystems Contact Us Group Leader (acting) Bob Roback Email Deputy Group Leader (acting) Jeff Heikoop Email Profile pages header Search our Profile pages

  8. Free kick instead of cross-validation in maximum-likelihood refinement of macromolecular crystal structures

    SciTech Connect (OSTI)

    Pranikar, Jure [Institute Joef Stefan, Jamova 39, 1000 Ljubljana (Slovenia); University of Primorska, (Slovenia); Turk, Duan, E-mail: dusan.turk@ijs.si [Institute Joef Stefan, Jamova 39, 1000 Ljubljana (Slovenia); Center of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, (Slovenia)

    2014-12-01

    The maximum-likelihood free-kick target, which calculates model error estimates from the work set and a randomly displaced model, proved superior in the accuracy and consistency of refinement of crystal structures compared with the maximum-likelihood cross-validation target, which calculates error estimates from the test set and the unperturbed model. The refinement of a molecular model is a computational procedure by which the atomic model is fitted to the diffraction data. The commonly used target in the refinement of macromolecular structures is the maximum-likelihood (ML) function, which relies on the assessment of model errors. The current ML functions rely on cross-validation. They utilize phase-error estimates that are calculated from a small fraction of diffraction data, called the test set, that are not used to fit the model. An approach has been developed that uses the work set to calculate the phase-error estimates in the ML refinement from simulating the model errors via the random displacement of atomic coordinates. It is called ML free-kick refinement as it uses the ML formulation of the target function and is based on the idea of freeing the model from the model bias imposed by the chemical energy restraints used in refinement. This approach for the calculation of error estimates is superior to the cross-validation approach: it reduces the phase error and increases the accuracy of molecular models, is more robust, provides clearer maps and may use a smaller portion of data for the test set for the calculation of R{sub free} or may leave it out completely.

  9. Variable Compression Ratio Engine | Department of Energy

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

    Compression Ratio Engine Variable Compression Ratio Engine 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. PDF icon ace_43_mendler.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: High Efficiency VCR Engine with Variable Valve Actuation and new Supercharging Technology Vehicle Technologies Office Merit Review 2015: High Efficiency VCR Engine with Variable Valve

  10. Eccentric crank variable compression ratio mechanism

    DOE Patents [OSTI]

    Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)

    2008-05-13

    A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

  11. Alaska Maximum Number of Active Crews Engaged in Three-Dimensional Seismic

    Gasoline and Diesel Fuel Update (EIA)

    Surveying (Number of Elements) Three-Dimensional Seismic Surveying (Number of Elements) Alaska Maximum Number of Active Crews Engaged in Three-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 1 2 2 2 1 1 0 0 0 0 2001 0 0 0 0 1 1 0 0 0 0 0 0 2002 1 1 1 1 1 1 1 1 1 1 1 0 2003 0 0 1 1 1 1 1 1

  12. A New Maximum-Likelihood Change Estimator for Two-Pass SAR Coherent Change Detection.

    SciTech Connect (OSTI)

    Wahl, Daniel E.; Yocky, David A.; Jakowatz, Charles V,

    2014-09-01

    In this paper, we derive a new optimal change metric to be used in synthetic aperture RADAR (SAR) coherent change detection (CCD). Previous CCD methods tend to produce false alarm states (showing change when there is none) in areas of the image that have a low clutter-to-noise power ratio (CNR). The new estimator does not suffer from this shortcoming. It is a surprisingly simple expression, easy to implement, and is optimal in the maximum-likelihood (ML) sense. The estimator produces very impressive results on the CCD collects that we have tested.

  13. WIND VARIABILITY IN BZ CAMELOPARDALIS

    SciTech Connect (OSTI)

    Honeycutt, R. K.; Kafka, S.; Robertson, J. W. E-mail: skafka@dtm.ciw.edu

    2013-02-01

    Sequences of spectra of the nova-like cataclysmic variable (CV) BZ Cam were acquired on nine nights in 2005-2006 in order to study the time development of episodes of wind activity known to occur frequently in this star. We confirm the results of Ringwald and Naylor that the P-Cygni absorption components of the lines mostly evolve from higher expansion velocity to lower velocity as an episode progresses. We also commonly find blueshifted emission components in the H{alpha} line profile, whose velocities and durations strongly suggest that they are also due to the wind. Curiously, Ringwald and Naylor reported common occurrences of redshifted H{alpha} emission components in their BZ Cam spectra. We have attributed these emission components in H{alpha} to occasions when gas concentrations in the bipolar wind (both front side and back side) become manifested as emission lines as they move beyond the disk's outer edge. We also suggest, based on changes in the P-Cygni profiles during an episode, that the progression from larger to smaller expansion velocities is due to the higher velocity portions of a wind concentration moving beyond the edge of the continuum light of the disk first, leaving a net redward shift of the remaining absorption profile. We derive a new orbital ephemeris for BZ Cam, using the radial velocity of the core of the He I {lambda}5876 line, finding P = 0.15353(4). Using this period, the wind episodes in BZ Cam are found to be concentrated near the inferior conjunction of the emission line source. This result helps confirm that the winds in nova-like CVs are often phase dependent, in spite of the puzzling implication that such winds lack axisymmetry. We argue that the radiation-driven wind in BZ Cam receives an initial boost by acting on gas that has been lifted above the disk by the interaction of the accretion stream with the disk, thereby imposing flickering timescales onto the wind events, as well as leading to an orbital modulation of the wind due to the non-axisymmetric nature of the stream/disk interaction. Simultaneous photometry and spectroscopy were acquired on three nights in order to test the possible connection between flickering continuum light and the strength of the front-side wind. We found strong agreement on one night, some agreement on another, and no agreement on the third. We suggest that some flickering events lead to only back-side winds which will not have associated P-Cygni profiles.

  14. Variables Affecting Economic Development of Wind Energy

    SciTech Connect (OSTI)

    Lantz, E.; Tegen, S.

    2008-02-01

    Report on the specific factors driving wind-power-related economic development and on the impact of specific economic development variables on new wind project economic benefits.

  15. Variable-Period Undulators For Synchrotron Radiation

    DOE Patents [OSTI]

    Shenoy, Gopal (Naperville, IL); Lewellen, John (Plainfield, IL); Shu, Deming (Darien, IL); Vinokurov, Nikolai (Novosibirsk, RU)

    2005-02-22

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high-energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  16. Variable orifice using an iris shutter

    DOE Patents [OSTI]

    Beeman, Raymond (El Cerrito, CA); Brajkovich, Steven J. (Fremont, CA)

    1978-01-01

    A variable orifice forming mechanism utilizing an iris shutter arrangement adapted to control gas flow, conductance in vacuum systems, as a heat shield for furnace windows, as a beam shutter in sputtering operations, and in any other application requiring periodic or continuously-variable control of material, gas, or fluid flow.

  17. HCCI in a Variable Compression Ratio Engine: Effects of Engine Variables |

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

    Department of Energy in a Variable Compression Ratio Engine: Effects of Engine Variables HCCI in a Variable Compression Ratio Engine: Effects of Engine Variables 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Southwest Research Institute PDF icon 2004_deer_ryan.pdf More Documents & Publications HCCI - A Technical Review and Progress Report 2006 HCCI - Update of Progress 2005 Fuel Requirements for HCCI Engine Operation

  18. Alaska Maximum Number of Active Crews Engaged in Two-Dimensional Seismic

    Gasoline and Diesel Fuel Update (EIA)

    Surveying (Number of Elements) Two-Dimensional Seismic Surveying (Number of Elements) Alaska Maximum Number of Active Crews Engaged in Two-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 1 1 1 1 0 0 0 0 0 0 2001 0 0 0 0 1 1 0 0 0 0 0 0 2002 1 1 1 1 1 1 1 1 1 1 1 1 2003 0 0 1 1 1 1 1 1 0 0 0 0 2004 0 0 0 0 0 0 0 0 0 0 0 0 2005 0 0 0 0 0 0 0 0 0 0 0 0 2006 0 0 0 0 0 0 0 0 0 0 0 0 2007 0 0 0 0 0 0 0 0 0 0 0 0 2008 0 0 0 0 0 0 0 0

  19. Maximum Achievable Control Technology for New Industrial Boilers (released in AEO2005)

    Reports and Publications (EIA)

    2005-01-01

    As part of Clean Air Act 90 (CAAA90, the EPA on February 26, 2004, issued a final rulethe National Emission Standards for Hazardous Air Pollutants (NESHAP) to reduce emissions of hazardous air pollutants (HAPs) from industrial, commercial, and institutional boilers and process heaters. The rule requires industrial boilers and process heaters to meet limits on HAP emissions to comply with a Maximum Achievable Control Technology (MACT) floor level of control that is the minimum level such sources must meet to comply with the rule. The major HAPs to be reduced are hydrochloric acid, hydrofluoric acid, arsenic, beryllium, cadmium, and nickel. The EPA predicts that the boiler MACT rule will reduce those HAP emissions from existing sources by about 59,000 tons per year in 2005.

  20. U.S.Lower 48 States Offshore Maximum Number of Active Crews Engaged in

    Gasoline and Diesel Fuel Update (EIA)

    Four-Dimensional Seismic Surveying (Number of Elements) Four-Dimensional Seismic Surveying (Number of Elements) U.S.Lower 48 States Offshore Maximum Number of Active Crews Engaged in Four-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 NA NA 0 0 0 0 0 0 0 0 0 0 2001 0 0 0 0 0 0 0 0 0 0 0 0 2002 0 0 0 0 0 0 0 0 0 0 0 0 2003 0 0 0 0 0 0 0 0 0 0 0 0 2004 0 0 0 0 0 0 0 0 0 0 0 0 2005 0 0 0 0 0 0 0 0 0 0 0 0 2006 0 0 0 0 0 0 0 0 0 0 0 0

  1. U.S.Lower 48 States Offshore Maximum Number of Active Crews Engaged in

    Gasoline and Diesel Fuel Update (EIA)

    Three-Dimensional Seismic Surveying (Number of Elements) Three-Dimensional Seismic Surveying (Number of Elements) U.S.Lower 48 States Offshore Maximum Number of Active Crews Engaged in Three-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 11 11 11 9 6 7 8 9 8 8 2001 7 7 9 9 8 7 8 8 9 10 10 9 2002 6 6 7 7 8 7 8 7 7 7 5 4 2003 4 4 4 4 4 4 4 4 2 3 3 5 2004 5 5 5 4 4 4 4 4 2 2 4 4 2005 4 4 6 6 6 5 5 5 5 5 5 5 2006 5 6 6 6 6 5 5 5 5

  2. U.S.Lower 48 States Offshore Maximum Number of Active Crews Engaged in

    Gasoline and Diesel Fuel Update (EIA)

    Two-Dimensional Seismic Surveying (Number of Elements) Two-Dimensional Seismic Surveying (Number of Elements) U.S.Lower 48 States Offshore Maximum Number of Active Crews Engaged in Two-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 7 7 6 7 6 7 7 7 7 8 2001 9 8 9 9 9 9 8 7 6 9 7 8 2002 8 9 10 9 9 9 8 8 10 10 8 7 2003 8 8 7 7 8 8 7 7 7 5 4 5 2004 5 5 5 5 5 4 4 4 4 2 1 3 2005 5 5 6 6 7 7 6 6 6 6 6 6 2006 6 6 6 5 5 7 4 3 2 2 3 3

  3. U.S.Lower 48 States Onshore Maximum Number of Active Crews Engaged in

    Gasoline and Diesel Fuel Update (EIA)

    Four-Dimensional Seismic Surveying (Number of Elements) Four-Dimensional Seismic Surveying (Number of Elements) U.S.Lower 48 States Onshore Maximum Number of Active Crews Engaged in Four-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 1 1 1 1 1 1 1 1 1 1 2001 1 1 1 1 1 1 1 1 1 1 1 1 2002 0 0 0 0 0 0 0 0 0 0 0 0 2003 1 0 0 0 0 0 0 0 0 0 0 0 2004 0 0 0 0 0 0 0 0 0 0 0 0 2005 0 0 0 0 0 0 0 0 0 0 0 0 2006 0 0 0 0 0 0 0 0 0 0 0 0

  4. U.S.Lower 48 States Onshore Maximum Number of Active Crews Engaged in

    Gasoline and Diesel Fuel Update (EIA)

    Three-Dimensional Seismic Surveying (Number of Elements) Three-Dimensional Seismic Surveying (Number of Elements) U.S.Lower 48 States Onshore Maximum Number of Active Crews Engaged in Three-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 36 36 34 37 39 40 39 41 40 41 2001 38 38 38 39 37 35 35 32 30 33 34 33 2002 32 31 26 25 24 23 26 26 28 30 27 22 2003 19 20 20 20 17 18 21 22 22 24 24 25 2004 25 27 27 27 26 30 30 31 32 34 33 32

  5. U.S.Lower 48 States Onshore Maximum Number of Active Crews Engaged in

    Gasoline and Diesel Fuel Update (EIA)

    Two-Dimensional Seismic Surveying (Number of Elements) Two-Dimensional Seismic Surveying (Number of Elements) U.S.Lower 48 States Onshore Maximum Number of Active Crews Engaged in Two-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2000 0 0 4 4 3 5 4 4 3 4 4 5 2001 5 6 6 7 7 6 6 8 8 5 7 7 2002 6 9 9 7 8 9 8 7 9 8 8 8 2003 8 9 8 7 7 7 7 8 8 7 7 7 2004 8 8 8 9 9 9 8 8 8 8 9 9 2005 8 8 6 8 8 9 8 8 7 6 5 6 2006 5 5 4 4 4 9 5 4 4 5 5 5 2007

  6. A new maximum-likelihood change estimator for two-pass SAR coherent change detection

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wahl, Daniel E.; Yocky, David A.; Jakowatz, Jr., Charles V.; Simonson, Katherine Mary

    2016-01-11

    In past research, two-pass repeat-geometry synthetic aperture radar (SAR) coherent change detection (CCD) predominantly utilized the sample degree of coherence as a measure of the temporal change occurring between two complex-valued image collects. Previous coherence-based CCD approaches tend to show temporal change when there is none in areas of the image that have a low clutter-to-noise power ratio. Instead of employing the sample coherence magnitude as a change metric, in this paper, we derive a new maximum-likelihood (ML) temporal change estimate—the complex reflectance change detection (CRCD) metric to be used for SAR coherent temporal change detection. The new CRCD estimatormore » is a surprisingly simple expression, easy to implement, and optimal in the ML sense. As a result, this new estimate produces improved results in the coherent pair collects that we have tested.« less

  7. Thirty-Year Solid Waste Generation Maximum and Minimum Forecast for SRS

    SciTech Connect (OSTI)

    Thomas, L.C.

    1994-10-01

    This report is the third phase (Phase III) of the Thirty-Year Solid Waste Generation Forecast for Facilities at the Savannah River Site (SRS). Phase I of the forecast, Thirty-Year Solid Waste Generation Forecast for Facilities at SRS, forecasts the yearly quantities of low-level waste (LLW), hazardous waste, mixed waste, and transuranic (TRU) wastes generated over the next 30 years by operations, decontamination and decommissioning and environmental restoration (ER) activities at the Savannah River Site. The Phase II report, Thirty-Year Solid Waste Generation Forecast by Treatability Group (U), provides a 30-year forecast by waste treatability group for operations, decontamination and decommissioning, and ER activities. In addition, a 30-year forecast by waste stream has been provided for operations in Appendix A of the Phase II report. The solid wastes stored or generated at SRS must be treated and disposed of in accordance with federal, state, and local laws and regulations. To evaluate, select, and justify the use of promising treatment technologies and to evaluate the potential impact to the environment, the generic waste categories described in the Phase I report were divided into smaller classifications with similar physical, chemical, and radiological characteristics. These smaller classifications, defined within the Phase II report as treatability groups, can then be used in the Waste Management Environmental Impact Statement process to evaluate treatment options. The waste generation forecasts in the Phase II report includes existing waste inventories. Existing waste inventories, which include waste streams from continuing operations and stored wastes from discontinued operations, were not included in the Phase I report. Maximum and minimum forecasts serve as upper and lower boundaries for waste generation. This report provides the maximum and minimum forecast by waste treatability group for operation, decontamination and decommissioning, and ER activities.

  8. Initial results from NuSTAR observations of the Norma Arm

    SciTech Connect (OSTI)

    Bodaghee, Arash; Tomsick, John A.; Krivonos, Roman; Barrire, Nicolas; Boggs, Steven E.; Craig, William W.; Stern, Daniel; Bauer, Franz E.; Fornasini, Francesca M.; Christensen, Finn E.; Gotthelf, Eric V.; Hailey, Charles J.; Mori, Kaya; Harrison, Fiona A.; Hong, Jaesub; Zhang, William W.

    2014-08-10

    Results are presented for an initial survey of the Norma Arm gathered with the focusing hard X-Ray Telescope NuSTAR. The survey covers 0.2 deg{sup 2} of sky area in the 3-79 keV range with a minimum and maximum raw depth of 15 ks and 135 ks, respectively. Besides a bright black-hole X-ray binary in outburst (4U 163047) and a new X-ray transient (NuSTAR J163433473841), NuSTAR locates three sources from the Chandra survey of this region whose spectra are extended above 10 keV for the first time: CXOU J163329.5473332, CXOU J163350.9474638, and CXOU J163355.1473804. Imaging, timing, and spectral data from a broad X-ray range (0.3-79 keV) are analyzed and interpreted with the aim of classifying these objects. CXOU J163329.5473332 is either a cataclysmic variable or a faint low-mass X-ray binary. CXOU J163350.9474638 varies in intensity on year-long timescales, and with no multi-wavelength counterpart, it could be a distant X-ray binary or possibly a magnetar. CXOU J163355.1473804 features a helium-like iron line at 6.7 keV and is classified as a nearby cataclysmic variable. Additional surveys are planned for the Norma Arm and Galactic Center, and those NuSTAR observations will benefit from the lessons learned during this pilot study.

  9. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude

    DOE Patents [OSTI]

    Bogaty, J.M.; Clifft, B.E.; Bollinger, L.M.

    1995-08-08

    A beam current limiter is disclosed for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region. The system thus provides a large dynamic range in combination with good linearity. 6 figs.

  10. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude

    DOE Patents [OSTI]

    Bogaty, John M. (Lombard, IL); Clifft, Benny E. (Park Forest, IL); Bollinger, Lowell M. (Downers Grove, IL)

    1995-01-01

    A beam current limiter for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region. The system thus provides a large dynamic range in combination with good linearity.

  11. PV output variability modeling using satellite imagery.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Ellis, Abraham; Reno, Matthew J.

    2010-11-01

    High frequency irradiance variability measured on the ground is caused by the formation, dissipation, and passage of clouds in the sky. If we can identify and associate different cloud types/patterns from satellite imagery, we may be able to predict irradiance variability in areas lacking sensors. With satellite imagery covering the entire U.S., this allows for more accurate integration planning and power flow modeling over wide areas. Satellite imagery from southern Nevada was analyzed at 15 minute intervals over a year. Methods for image stabilization, cloud detection, and textural classification of clouds were developed and tested. High Performance Computing parallel processing algorithms were also investigated and tested. Artificial Neural Networks using imagery as inputs were trained on ground-based measurements of irradiance to model the variability and were tested to show some promise as a means for predicting irradiance variability.

  12. ESTIMATE OF SOLAR MAXIMUM USING THE 1-8 GEOSTATIONARY OPERATIONAL ENVIRONMENTAL SATELLITES X-RAY MEASUREMENTS

    SciTech Connect (OSTI)

    Winter, L. M.; Balasubramaniam, K. S.

    2014-10-01

    We present an alternate method of determining the progression of the solar cycle through an analysis of the solar X-ray background. Our results are based on the NOAA Geostationary Operational Environmental Satellites (GOES) X-ray data in the 1-8 band from 1986 to the present, covering solar cycles 22, 23, and 24. The X-ray background level tracks the progression of the solar cycle through its maximum and minimum. Using the X-ray data, we can therefore make estimates of the solar cycle progression and the date of solar maximum. Based upon our analysis, we conclude that the Sun reached its hemisphere-averaged maximum in solar cycle 24 in late 2013. This is within six months of the NOAA prediction of a maximum in spring 2013.

  13. Robust Maximum Lifetime Routing and Energy Allocation in Wireless Sensor Networks

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Paschalidis, Ioannis Ch.; Wu, Ruomin

    2012-01-01

    We consider the maximum lifetime routing problem in wireless sensor networks in two settings: (a) when nodes’ initial energy is given and (b) when it is subject to optimization. The optimal solution and objective value provide optimal flows and the corresponding predicted lifetime, respectively. We stipulate that there is uncertainty in various network parameters (available energy and energy depletion rates). In setting (a) we show that for specific, yet typical, network topologies, the actual network lifetime will reach the predicted value with a probability that converges to zero as the number of nodes grows large. In setting (b) the samemore » result holds for all topologies. We develop a series of robust problem formulations, ranging from pessimistic to optimistic. A set of parameters enable the tuning of the conservatism of the formulation to obtain network flows with a desirably high probability that the corresponding lifetime prediction is achieved. We establish a number of properties for the robust network flows and energy allocations and provide numerical results to highlight the tradeoff between predicted lifetime and the probability achieved. Further, we analyze an interesting limiting regime of massively deployed sensor networks and essentially solve a continuous version of the problem.« less

  14. Maximum Diameter Measurements of Aortic Aneurysms on Axial CT Images After Endovascular Aneurysm Repair: Sufficient for Follow-up?

    SciTech Connect (OSTI)

    Baumueller, Stephan Nguyen, Thi Dan Linh Goetti, Robert Paul; Lachat, Mario; Seifert, Burkhardt; Pfammatter, Thomas Frauenfelder, Thomas

    2011-12-15

    Purpose: To assess the accuracy of maximum diameter measurements of aortic aneurysms after endovascular aneurysm repair (EVAR) on axial computed tomographic (CT) images in comparison to maximum diameter measurements perpendicular to the intravascular centerline for follow-up by using three-dimensional (3D) volume measurements as the reference standard. Materials and Methods: Forty-nine consecutive patients (73 {+-} 7.5 years, range 51-88 years), who underwent EVAR of an infrarenal aortic aneurysm were retrospectively included. Two blinded readers twice independently measured the maximum aneurysm diameter on axial CT images performed at discharge, and at 1 and 2 years after intervention. The maximum diameter perpendicular to the centerline was automatically measured. Volumes of the aortic aneurysms were calculated by dedicated semiautomated 3D segmentation software (3surgery, 3mensio, the Netherlands). Changes in diameter of 0.5 cm and in volume of 10% were considered clinically significant. Intra- and interobserver agreements were calculated by intraclass correlations (ICC) in a random effects analysis of variance. The two unidimensional measurement methods were correlated to the reference standard. Results: Intra- and interobserver agreements for maximum aneurysm diameter measurements were excellent (ICC = 0.98 and ICC = 0.96, respectively). There was an excellent correlation between maximum aneurysm diameters measured on axial CT images and 3D volume measurements (r = 0.93, P < 0.001) as well as between maximum diameter measurements perpendicular to the centerline and 3D volume measurements (r = 0.93, P < 0.001). Conclusion: Measurements of maximum aneurysm diameters on axial CT images are an accurate, reliable, and robust method for follow-up after EVAR and can be used in daily routine.

  15. VariableR Reclustering in Multiple Top Quark and W Boson Events

    SciTech Connect (OSTI)

    Hyde, Jeremy

    2015-08-14

    VariableR jet reclustering is an innovative technique that allows for the reconstruction of boosted object over a wide range of kinematic regimes. Such capability enables the efficient identification of events with multiple boosted top quarks which is a typical signature for new physics processes such as the production of the supersymmetric partner of the gluon. In order to evaluate the performance of the algorithm, the VariableR reclustered jets are compared with fixed radius reclustered jets. The flexibility of the algorithm is tested by reconstructing both boosted top quarks and boosted W bosons. The VariableR reclustering method is found to be more efficient than the fixed radius algorithm at identifying top quarks and W bosons in events with four top quarks, therefore enhancing the sensitivity for gluino searches.

  16. Estimating the age of alleles by use of intraallelic variability

    SciTech Connect (OSTI)

    Slatkin, M.; Rannala, B.

    1997-02-01

    A method is presented for estimating the age of an allele by use of its frequency and the extent of variation among different copies. The method uses the joint distribution of the number of copies in a population sample and the coalescence times of the intraallelic gene genealogy conditioned on the number of copies. The linear birth-death process is used to approximate the dynamics of a rare allele in a finite population. A maximum-likelihood estimate of the age of the allele is obtained by Monte Carlo integration over the coalescence times. The method is applied to two alleles at the cystic fibrosis (CFTR) locus, {Delta}F508 and G542X, for which intraallelic variability at three intronic microsatellite loci has been examined. Our results indicate that G542X is somewhat older than {Delta}F508. Although absolute estimates depend on the mutation rates at the microsatellite loci, our results support the hypothesis that {Delta}F508 arose <500 generations ({approx}10,000 years) ago. 32 refs., 4 figs.

  17. Cataclysmic variables in the SUPERBLINK proper motion survey

    SciTech Connect (OSTI)

    Skinner, Julie N.; Thorstensen, John R.; Lpine, Sbastien

    2014-12-01

    We have discovered a new high proper motion cataclysmic variable (CV) in the SUPERBLINK proper motion survey, which is sensitive to stars with proper motions greater than 40 mas yr{sup ?1}. This CV was selected for follow-up observations as part of a larger search for CVs selected based on proper motions and their near-UV?V and V?K{sub s} colors. We present spectroscopic observations from the 2.4 m Hiltner Telescope at MDM Observatory. The new CV's orbital period is near 96 minutes, its spectrum shows the double-peaked Balmer emission lines characteristic of quiescent dwarf novae, and its V magnitude is near 18.2. Additionally, we present a full list of known CVs in the SUPERBLINK catalog.

  18. Measuring spatial variability in soil characteristics

    DOE Patents [OSTI]

    Hoskinson, Reed L. (Rigby, ID); Svoboda, John M. (Idaho Falls, ID); Sawyer, J. Wayne (Hampton, VA); Hess, John R. (Ashton, ID); Hess, J. Richard (Idaho Falls, ID)

    2002-01-01

    The present invention provides systems and methods for measuring a load force associated with pulling a farm implement through soil that is used to generate a spatially variable map that represents the spatial variability of the physical characteristics of the soil. An instrumented hitch pin configured to measure a load force is provided that measures the load force generated by a farm implement when the farm implement is connected with a tractor and pulled through or across soil. Each time a load force is measured, a global positioning system identifies the location of the measurement. This data is stored and analyzed to generate a spatially variable map of the soil. This map is representative of the physical characteristics of the soil, which are inferred from the magnitude of the load force.

  19. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, O.A.

    1988-07-13

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90/degree/ intervals with opposing electrodes maintained at the same potential. 12 figs., 3 tabs.

  20. Observations

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

    sulla Fusione, Corso Stati Uniti, 4 35127 Padova, Italy * 2 Istituto Nazionale di Fisica della Materia, UdR Padova, Italy 3 Department of Physics, University of ...

  1. Observation

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

    P. Martin Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, 35127 Padova, Italy and Istituto Nazionale Fisica della Materia, INFM, Padova, Italy G. ...

  2. Observation

    Office of Scientific and Technical Information (OSTI)

    to an Orbital-Selective Mott Phase in A x Fe 2-y Se 2 (AK, Rb) Superconductors M. Yi, 1, 2 D. H. Lu, 3 R. Yu, 4 S. C. Riggs, 1, 2 J.-H. Chu, 1, 2 B. Lv, 5 Z. Liu, 1, 2 M. Lu,...

  3. Integrating Variable Renewable Energy: Challenges and Solutions

    SciTech Connect (OSTI)

    Bird, L.; Milligan, M.; Lew, D.

    2013-09-01

    In the U.S., a number of utilities are adopting higher penetrations of renewables, driven in part by state policies. While power systems have been designed to handle the variable nature of loads, the additional supply-side variability and uncertainty can pose new challenges for utilities and system operators. However, a variety of operational and technical solutions exist to help integrate higher penetrations of wind and solar generation. This paper explores renewable energy integration challenges and mitigation strategies that have been implemented in the U.S. and internationally, including forecasting, demand response, flexible generation, larger balancing areas or balancing area cooperation, and operational practices such as fast scheduling and dispatch.

  4. Variable pressure power cycle and control system

    DOE Patents [OSTI]

    Goldsberry, Fred L.

    1984-11-27

    A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

  5. Field observations and lessons learned

    SciTech Connect (OSTI)

    Nielsen, Joh B

    2010-01-01

    This presentation outlines observations and lessons learned from the Megaports program. It provides: (1) details of field and technical observations collected during LANL field activities at ports around the world and details of observations collected during radiation detections system testing at Los Alamos National Laboratory; (2) provides suggestions for improvement and efficiency; and (3) discusses possible program execution changes for more effective operations.

  6. Production-Intent Lost-Motion Variable Valve Actuation Systems...

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

    Production-Intent Lost-Motion Variable Valve Actuation Systems Production-Intent Lost-Motion Variable Valve Actuation Systems Variable valve actuation with onoff IEGR pre-bump is ...

  7. Compact, electro-hydraulic, variable valve actuation system providing

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

    variable lift, timing and duration to enable high efficiency engine combustion control | Department of Energy Compact, electro-hydraulic, variable valve actuation system providing variable lift, timing and duration to enable high efficiency engine combustion control Compact, electro-hydraulic, variable valve actuation system providing variable lift, timing and duration to enable high efficiency engine combustion control Discusses development of advanced variable valve actuation system to

  8. The variable sky of deep synoptic surveys

    SciTech Connect (OSTI)

    Ridgway, Stephen T.; Matheson, Thomas; Mighell, Kenneth J.; Olsen, Knut A. [National Optical Astronomy Observatory, Tucson, AZ 85725 (United States); Howell, Steve B., E-mail: ridgway@noao.edu [NASA Ames Research Center, P.O. Box 1, M/S 244-30, Moffett Field, CA 94035 (United States)

    2014-11-20

    The discovery of variable and transient sources is an essential product of synoptic surveys. The alert stream will require filtering for personalized criteriaa process managed by a functionality commonly described as a Broker. In order to understand quantitatively the magnitude of the alert generation and Broker tasks, we have undertaken an analysis of the most numerous types of variable targets in the skyGalactic stars, quasi-stellar objects (QSOs), active galactic nuclei (AGNs), and asteroids. It is found that the Large Synoptic Survey Telescope (LSST) will be capable of discovering ?10{sup 5} high latitude (|b| > 20) variable stars per night at the beginning of the survey. (The corresponding number for |b| < 20 is orders of magnitude larger, but subject to caveats concerning extinction and crowding.) However, the number of new discoveries may well drop below 100 per night within less than one year. The same analysis applied to GAIA clarifies the complementarity of the GAIA and LSST surveys. Discovery of AGNs and QSOs are each predicted to begin at ?3000 per night and decrease by 50 times over four years. Supernovae are expected at ?1100 per night, and after several survey years will dominate the new variable discovery rate. LSST asteroid discoveries will start at >10{sup 5} per night, and if orbital determination has a 50% success rate per epoch, they will drop below 1000 per night within two years.

  9. Chapter 18: Variable Frequency Drive Evaluation Protocol

    SciTech Connect (OSTI)

    Romberger, J.

    2014-11-01

    An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

  10. Galactic Variable Sky with EGRET and GLAST

    SciTech Connect (OSTI)

    Digel, S.W.; /SLAC

    2006-11-28

    The characteristics of the largely-unidentified Galactic sources of gamma rays that were detected by EGRET are reviewed. Proposed source populations that may have the correct spatial, spectral, luminosity, and variability properties to be the origins of the EGRET sources are also presented. Finally, the prospects for studying Galactic gamma-ray sources with the GLAST LAT are reviewed.

  11. Evaluation of a photovoltaic energy mechatronics system with a built-in quadratic maximum power point tracking algorithm

    SciTech Connect (OSTI)

    Chao, R.M.; Ko, S.H.; Lin, I.H.; Pai, F.S.; Chang, C.C.

    2009-12-15

    The historically high cost of crude oil price is stimulating research into solar (green) energy as an alternative energy source. In general, applications with large solar energy output require a maximum power point tracking (MPPT) algorithm to optimize the power generated by the photovoltaic effect. This work aims to provide a stand-alone solution for solar energy applications by integrating a DC/DC buck converter to a newly developed quadratic MPPT algorithm along with its appropriate software and hardware. The quadratic MPPT method utilizes three previously used duty cycles with their corresponding power outputs. It approaches the maximum value by using a second order polynomial formula, which converges faster than the existing MPPT algorithm. The hardware implementation takes advantage of the real-time controller system from National Instruments, USA. Experimental results have shown that the proposed solar mechatronics system can correctly and effectively track the maximum power point without any difficulties. (author)

  12. Variable Speed Pumping: A Guide to Successful Applications -...

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

    Variable Speed Pumping: A Guide to Successful Applications - Executive Summary Variable Speed Pumping: A Guide to Successful Applications - Executive Summary This document ...

  13. Control Strategies for Centrifugal Pumps with Variable Flow Rate...

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

    Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements This tip sheet discusses...

  14. Carderock 3-ft Variable Pressure Cavitation Water Tunnel | Open...

    Open Energy Info (EERE)

    3-ft Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 3-ft Variable Pressure Cavitation Water Tunnel Overseeing...

  15. Carderock 2-ft Variable Pressure Cavitation Water Tunnel | Open...

    Open Energy Info (EERE)

    is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Towing...

  16. Self-Referenced Continuous-Variable Quantum Key Distribution...

    Office of Scientific and Technical Information (OSTI)

    Self-Referenced Continuous-Variable Quantum Key Distribution Protocol Citation Details In-Document Search Title: Self-Referenced Continuous-Variable Quantum Key Distribution ...

  17. Estimation and Control of Diesel Engine Processes Utilizing Variable...

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

    Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve Actuation Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve ...

  18. Demonstration of a Variable Phase Turbine Power System for Low...

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

    Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources Demonstration of a Variable Phase Turbine Power System for Low Temperature ...

  19. Enabling High Efficiency Clean Combustion with Micro-Variable...

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

    Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI Enabling High Efficiency Clean Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel ...

  20. Adaptive PCCI with Variable Orifice Injector for Low Cost High...

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

    Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency Clean Diesels Adaptive PCCI with Variable Orifice Injector for Low Cost High Efficiency Clean Diesels ...

  1. Two-Stage Variable Compression Ratio (VCR) System to Increase...

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

    Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline ...

  2. Thermodynamic properties of mesoscale convective systems observed during BAMEX

    SciTech Connect (OSTI)

    Correia, James; Arritt, R.

    2008-11-01

    Dropsonde observations from the Bow-echo and Mesoscale convective vortex EXperiment (BAMEX) are used to document the spatio-temporal variability of temperature, moisture and wind within mesoscale convective systems (MCSs). Onion type sounding structures are found throughout the stratiform region of MCSs but the temperature and moisture variability is large. Composite soundings were constructed and statistics of thermodynamic variability were generated within each sub-region of the MCS. The calculated air vertical velocity helped identify subsaturated downdrafts. We found that lapse rates within the cold pool varied markedly throughout the MCS. Layered wet bulb potential temperature profiles seem to indicate that air within the lowest several km comes from a variety of source regions. We also found that lapse rate transitions across the 0 C level were more common than isothermal, melting layers. We discuss the implications these findings have and how they can be used to validate future high resolution numerical simulations of MCSs.

  3. Application of the Principle of Maximum Conformality to Top-Pair Production

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; Wu, Xing-Gang; /SLAC /Chongqing U.

    2013-05-13

    A major contribution to the uncertainty of finite-order perturbative QCD predictions is the perceived ambiguity in setting the renormalization scale {mu}{sub r}. For example, by using the conventional way of setting {mu}{sub r} {element_of} [m{sub t}/2, 2m{sub t}], one obtains the total t{bar t} production cross-section {sigma}{sub t{bar t}} with the uncertainty {Delta}{sigma}{sub t{bar t}}/{sigma}{sub t{bar t}} {approx} (+3%/-4%) at the Tevatron and LHC even for the present NNLO level. The Principle of Maximum Conformality (PMC) eliminates the renormalization scale ambiguity in precision tests of Abelian QED and non-Abelian QCD theories. By using the PMC, all nonconformal {l_brace}{beta}{sub i}{r_brace}-terms in the perturbative expansion series are summed into the running coupling constant, and the resulting scale-fixed predictions are independent of the renormalization scheme. The correct scale-displacement between the arguments of different renormalization schemes is automatically set, and the number of active flavors n{sub f} in the {l_brace}{beta}{sub i}{r_brace}-function is correctly determined. The PMC is consistent with the renormalization group property that a physical result is independent of the renormalization scheme and the choice of the initial renormalization scale {mu}{sub r}{sup init}. The PMC scale {mu}{sub r}{sup PMC} is unambiguous at finite order. Any residual dependence on {mu}{sub r}{sup init} for a finite-order calculation will be highly suppressed since the unknown higher-order {l_brace}{beta}{sub i}{r_brace}-terms will be absorbed into the PMC scales higher-order perturbative terms. We find that such renormalization group invariance can be satisfied to high accuracy for {sigma}{sub t{bar t}} at the NNLO level. In this paper we apply PMC scale-setting to predict the t{bar t} cross-section {sigma}{sub t{bar t}} at the Tevatron and LHC colliders. It is found that {sigma}{sub t{bar t}} remains almost unchanged by varying {mu}{sub r}{sup init} within the region of [m{sub t}/4, 4m{sub t}]. The convergence of the expansion series is greatly improved. For the (q{bar q})-channel, which is dominant at the Tevatron, its NLO PMC scale is much smaller than the top-quark mass in the small x-region, and thus its NLO cross-section is increased by about a factor of two. In the case of the (gg)-channel, which is dominant at the LHC, its NLO PMC scale slightly increases with the subprocess collision energy {radical}s, but it is still smaller than m{sub t} for {radical} {approx}< 1 TeV, and the resulting NLO cross-section is increased by {approx}20%. As a result, a larger {sigma}{sub t{bar t}} is obtained in comparison to the conventional scale-setting method, which agrees well with the present Tevatron and LHC data. More explicitly, by setting m{sub t} = 172.9 {+-} 1.1 GeV, we predict {sigma}{sub Tevatron, 1.96 TeV} = 7.626{sub -0.257}{sup +0.265} pb, {sigma}{sub LHC, 7 TeV} = 171.8{sub -5.6}{sup +5.8} pb and {sigma}{sub LHC, 14 TeV} = 941.3{sub -26.5}{sup +28.4} pb.

  4. Depth of maximum of air-shower profiles at the Pierre Auger Observatory. I. Measurements at energies above $$10^{17.8}$$ eV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aab, Alexander

    2014-12-31

    We report a study of the distributions of the depth of maximum, Xmax, of extensive air-shower profiles with energies above 1017.8 eV as observed with the fluorescence telescopes of the Pierre Auger Observatory. The analysis method for selecting a data sample with minimal sampling bias is described in detail as well as the experimental cross-checks and systematic uncertainties. Furthermore, we discuss the detector acceptance and the resolution of the Xmax measurement and provide parametrizations thereof as a function of energy. Finally, the energy dependence of the mean and standard deviation of the Xmax distributions are compared to air-shower simulations formore » different nuclear primaries and interpreted in terms of the mean and variance of the logarithmic mass distribution at the top of the atmosphere.« less

  5. The role of water vapor feedback in unperturbed climate variability and global warming

    SciTech Connect (OSTI)

    Hall, A.; Manabe, Syukuro

    1999-08-01

    To understand the role of water vapor feedback in unperturbed surface temperature variability, a version of the Geophysical Fluid Dynamics Laboratory coupled ocean-atmosphere model is integrated for 1,000 yr in two configurations, one with water vapor feedback and one without. To understand the role of water vapor feedback in global warming, two 500-yr integrations were also performed in which CO{sub 2} was doubled in both model configurations. The final surface global warming in the model with water vapor feedback is 3.38 C, while in the one without it is only 1.05 C. However, the model`s water vapor feedback has a larger impact on surface warming in response to a doubling of CO{sub 2} than it does on internally generated, low-frequency, global-mean surface temperature anomalies. Water vapor feedback`s strength therefore depends on the type of temperature anomaly it affects. Finally, the authors compare the local and global-mean surface temperature time series from both unperturbed variability experiments to the observed record. The experiment without water vapor feedback does not have enough global-scale variability to reproduce the magnitude of the variability in the observed global-mean record, whether or not one removes the warming trend observed over the past century. In contrast, the amount of variability in the experiment with water vapor feedback is comparable to that of the global-mean record, provided the observed warming trend is removed. Thus, the authors are unable to simulate the observed levels of variability without water vapor feedback.

  6. NS&T MANAGEMENT OBSERVATIONS

    SciTech Connect (OSTI)

    Gianotto, David

    2014-06-01

    The INL Management Observation Program (MOP) is designed to improve managers and supervisors understanding of work being performed by employees and the barriers impacting their success. The MOP also increases workers understanding of managements expectations as they relate to safety, security, quality, and work performance. Management observations (observations) are designed to improve the relationship and trust between employees and managers through increased engagement and interactions between managers and researchers in the field. As part of continuous improvement, NS&T management took initiative to focus on the participation and quality of observations in FY 14. This quarterly report is intended to (a) summarize the participation and quality of managements observations, (b) assess observations for commonalities or trends related to facility or process barriers impacting research, and (c) provide feedback and make recommendations for improvements NS&Ts MOP.

  7. NS&T Management Observations

    SciTech Connect (OSTI)

    Gianotto, David

    2014-09-01

    The INL Management Observation Program (MOP) is designed to improve managers and supervisors understanding of work being performed by employees and the barriers impacting their success. The MOP also increases workers understanding of managements expectations as they relate to safety, security, quality, and work performance. Management observations (observations) are designed to improve the relationship and trust between employees and managers through increased engagement and interactions between managers and researchers in the field. As part of continuous improvement, NS&T management took initiative to focus on the participation and quality of observations in FY 14. This quarterly report is intended to (a) summarize the participation and quality of managements observations, (b) assess observations for commonalities or trends related to facility or process barriers impacting research, and (c) provide feedback and make recommendations for improvements NS&Ts MOP.

  8. Final Technical Report: Low-Cost Solar Variability Sensors for Ubiquitous Deployment.

    SciTech Connect (OSTI)

    Lave, Matthew Samuel

    2016-01-01

    In this project, an integrated solution to measuring and collecting solar variability data called the solar variability datalogger (SVD) was developed, tested, and the value of its data to distribution grid integration studies was demonstrated. This work addressed the problem that high-frequency solar variability is rarely measured – due to the high cost and complex installation of existing solar irradiance measuring pyranometers – but is critical to the accurate determination of the impact of photovoltaics to electric grid operation. For example, up to a 300% difference in distribution grid voltage regulator tap change operations (a measure of the impact of PV) [1] has been observed due solely to different solar variability profiles.

  9. ARM - Surface Aerosol Observing System

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

    2009-2010 Shouxian, China, 2008 Black Forest, Germany, 2007 Niamey, Niger, 2006 Point Reyes, California, 2005 Surface Aerosol Observing System The ARM Mobile Facility (AMF) is...

  10. Fermi LAT Observations of LS 5039

    SciTech Connect (OSTI)

    Abdo, A.A.; Ackermann, M.; Ajello, M.; Atwood, W.B.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Baughman, B.M.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R.D.; Bloom, E.D.; Bonamente, E.; Borgland, A.W.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; /more authors..

    2012-03-29

    The first results from observations of the high-mass X-ray binary LS 5039 using the Fermi Gamma-ray Space Telescope data between 2008 August and 2009 June are presented. Our results indicate variability that is consistent with the binary period, with the emission being modulated with a period of 3.903 {+-} 0.005 days; the first detection of this modulation at GeV energies. The light curve is characterized by a broad peak around superior conjunction in agreement with inverse Compton scattering models. The spectrum is represented by a power law with an exponential cutoff, yielding an overall flux (100 MeV-300 GeV) of 4.9 {+-} 0.5(stat) {+-} 1.8(syst) x 10{sup -7} photon cm{sup -2} s{sup -1}, with a cutoff at 2.1 {+-} 0.3(stat) {+-} 1.1(syst) GeV and photon index {Gamma} = 1.9 {+-} 0.1(stat) {+-} 0.3(syst). The spectrum is observed to vary with orbital phase, specifically between inferior and superior conjunction. We suggest that the presence of a cutoff in the spectrum may be indicative of magnetospheric emission similar to the emission seen in many pulsars by Fermi.

  11. Thermodynamics in variable speed of light theories

    SciTech Connect (OSTI)

    Racker, Juan [CONICET, Centro Atomico Bariloche, Avenida Bustillo 9500 (8400), San Carlos De Bariloche (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina); Sisterna, Pablo [Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350 (7600), Mar del Plata (Argentina); Vucetich, Hector [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina)

    2009-10-15

    The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light (c), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of c is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

  12. Review of Variable Generation Integration Charges

    SciTech Connect (OSTI)

    Porter, K.; Fink, S.; Buckley, M.; Rogers, J.; Hodge, B. M.

    2013-03-01

    The growth of wind and solar generation in the United States, and the expectation of continued growth of these technologies, dictates that the future power system will be operated in a somewhat different manner because of increased variability and uncertainty. A small number of balancing authorities have attempted to determine an 'integration cost' to account for these changes to their current operating practices. Some balancing authorities directly charge wind and solar generators for integration charges, whereas others add integration charges to projected costs of wind and solar in integrated resource plans or in competitive solicitations for generation. This report reviews the balancing authorities that have calculated variable generation integration charges and broadly compares and contrasts the methodologies they used to determine their specific integration charges. The report also profiles each balancing authority and how they derived wind and solar integration charges.

  13. Variable aperture collimator for high energy radiation

    DOE Patents [OSTI]

    Hill, Ronald A. (Albuquerque, NM)

    1984-05-22

    An apparatus is disclosed providing a variable aperture energy beam collimator. A plurality of beam opaque blocks are in sliding interface edge contact to form a variable aperture. The blocks may be offset at the apex angle to provide a non-equilateral aperture. A plurality of collimator block assemblies may be employed for providing a channel defining a collimated beam. Adjacent assemblies are inverted front-to-back with respect to one another for preventing noncollimated energy from emerging from the apparatus. An adjustment mechanism comprises a cable attached to at least one block and a hand wheel mechanism for operating the cable. The blocks are supported by guide rods engaging slide brackets on the blocks. The guide rods are pivotally connected at each end to intermediate actuators supported on rotatable shafts to change the shape of the aperture. A divergent collimated beam may be obtained by adjusting the apertures of adjacent stages to be unequal.

  14. Sandia Labs releases wavelet variability model (WVM)

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

    releases wavelet variability model (WVM) - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management

  15. Intensive Variables & Nanostructuring in Magnetostructural Materials

    SciTech Connect (OSTI)

    Lewis, Laura

    2014-08-13

    Over the course of this project, fundamental inquiry was carried out to investigate, understand and predict the effects of intensive variables, including the structural scale, on magnetostructural phase transitions in the model system of equiatomic FeRh. These transitions comprise simultaneous magnetic and structural phase changes that have their origins in very strong orbital-lattice coupling and thus may be driven by a plurality of effects.

  16. Integrating Variable Renewable Energy: Challenges and Solutions

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

    Integrating Variable Renewable Energy: Challenges and Solutions L. Bird, M. Milligan, and D. Lew National Renewable Energy Laboratory Technical Report NREL/TP-6A20-60451 September 2013 NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency & Renewable Energy Operated by the Alliance for Sustainable Energy, LLC This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. Contract No.

  17. Resolved multifrequency radio observations of GG Tau

    SciTech Connect (OSTI)

    Andrews, Sean M.; Birnstiel, T.; Rosenfeld, K. A.; Wilner, D. J.; Chandler, Claire J.; Pérez, L. M.; Isella, Andrea; Ricci, L.; Carpenter, J. M.; Calvet, N.; Corder, S. A.; Deller, A. T.; Dullemond, C. P.; Greaves, J. S.; Harris, R. J.; Henning, Th.; Linz, H.; Kwon, W.; Lazio, J.; Mundy, L. G.; and others

    2014-06-01

    We present subarcsecond resolution observations of continuum emission associated with the GG Tau quadruple star system at wavelengths of 1.3, 2.8, 7.3, and 50 mm. These data confirm that the GG Tau A binary is encircled by a circumbinary ring at a radius of 235 AU with a FWHM width of ∼60 AU. We find no clear evidence for a radial gradient in the spectral shape of the ring, suggesting that the particle size distribution is spatially homogeneous on angular scales ≳0.''1. A central point source, likely associated with the primary component (GG Tau Aa), exhibits a composite spectrum from dust and free-free emission. Faint emission at 7.3 mm is observed toward the low-mass star GG Tau Ba, although its origin remains uncertain. Using these measurements of the resolved, multifrequency emission structure of the GG Tau A system, models of the far-infrared to radio spectrum are developed to place constraints on the grain size distribution and dust mass in the circumbinary ring. The non-negligible curvature present in the ring spectrum implies a maximum particle size of 1-10 mm, although we are unable to place strong constraints on the distribution shape. The corresponding dust mass is 30-300 M {sub ⊕}, at a temperature of 20-30 K. We discuss how this significant concentration of relatively large particles in a narrow ring at a large radius might be produced in a local region of higher gas pressures (i.e., a particle 'trap') located near the inner edge of the circumbinary disk.

  18. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, Oscar A. (Berkeley, CA)

    1990-01-01

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90.degree. intervals with opposing electrodes maintained at the same potential. Adjacent cylinder electrodes of the quadrupole structure are maintained at different potentials to thereby reshape the cross section of the charged particle beam to an ellipse in cross section at the mid point along each quadrupole electrode unit in the accelerator modules. The beam is maintained in focus by alternating the major axis of the ellipse along the x and y axis respectively at adjacent quadrupoles. In another embodiment, electrostatic ring electrodes may be utilized instead of the quadrupole electrodes.

  19. Investigating Broadband Variability of the TeV Blazar 1ES 1959+650

    SciTech Connect (OSTI)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Barnacka, A.; Beilicke, M.; Benbow, W.; Berger, K.; Bird, R.; Bouvier, A.; Buckley, J. H.; Bugaev, V.; Cerruti, M.; Chen, X.; Ciupik, L.; Collins-Hughes, E.; Connolly, M. P.; Cui, W.; Dumm, J.; Eisch, J. D.; Falcone, A.; Federici, S.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Hanna, D.; Holder, J.; Hughes, G.; Hughes, Z.; Humensky, T. B.; Johnson, C. A.; Kaaret, P.; Kar, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; Madhavan, A. S.; Majumdar, P.; McArthur, S.; McCann, A.; Meagher, K.; Millis, J.; Moriarty, P.; Mukherjee, R.; Nelson, T.; Nieto, D.; O'Faolain de Bhroithe, A.; Ong, R. A.; Otte, A. N.; Park, N.; Perkins, J. S.; Pohl, M.; Popkow, A.; Prokoph, H.; Quinn, J.; Ragan, K.; Rajotte, J.; Reyes, L. C.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Sadun, A.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Sheidaei, F.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Theiling, M.; Tyler, J.; Varlotta, A.; Vassiliev, V. V.; Vincent, S.; Wakeley, S. P.; Weekes, T. C.; Weinstein, A.; Welsing, R.; Wilhelm, A.; Williams, D. A.; Zitzer, B.; Boettcher, M.; Fumagalli, M.

    2014-12-03

    We summarize broadband observations of the TeV-emitting blazar 1ES 1959 650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift Ultraviolet and Optical Telescope, X-ray observations by the Swift X-ray Telescope, high-energy gamma-ray observations with the Fermi Large Area Telescope, and very-high-energy (VHE) gamma-ray observations by VERITAS above 315 GeV, all taken between 2012 April 17 and 2012 June 1 (MJD 56034 and 56079). The contemporaneous variability of the broadband spectral energy distribution is explored in the context of a simple synchrotron self Compton (SSC) model. In the SSC emission scenario, we find that the parameters required to represent the high state are significantly different than those in the low state. Motivated by possible evidence of gas in the vicinity of the blazar, we also investigate a reflected emission model to describe the observed variability pattern. This model assumes that the non-thermal emission from the jet is reflected by a nearby cloud of gas, allowing the reflected emission to re-enter the blob and produce an elevated gamma-ray state with no simultaneous elevated synchrotron flux. The model applied here, although not required to explain the observed variability pattern, represents one possible scenario which can describe the observations. As applied to an elevated VHE state of 66% of the Crab Nebula flux, observed on a single night during the observation period, the reflected emission scenario does not support a purely leptonic non-thermal emission mechanism. The reflected model does, however, predict a reflected photon field with sufficient energy to enable elevated gamma-ray emission via pion production with protons of energies between 10 and 100 TeV.

  20. Investigating broadband variability of the TeV blazar 1ES 1959+650

    SciTech Connect (OSTI)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Barnacka, A.; Beilicke, M.; Benbow, W.; Berger, K.; Bird, R.; Bouvier, A.; Buckley, J. H.; Bugaev, V.; Cerruti, M.; Chen, X.; Ciupik, L.; Collins-Hughes, E.; Connolly, M. P.; Cui, W.; Dumm, J.; Eisch, J. D.; Falcone, A.; Federici, S.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Fortin, P.; Fortson, L.; Furniss, A.; Galante, N.; Gillanders, G. H.; Griffin, S.; Griffiths, S. T.; Grube, J.; Gyuk, G.; Håkansson, N.; Hanna, D.; Holder, J.; Hughes, G.; Hughes, Z.; Humensky, T. B.; Johnson, C. A.; Kaaret, P.; Kar, P.; Kertzman, M.; Khassen, Y.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; Madhavan, A. S.; Majumdar, P.; McArthur, S.; McCann, A.; Meagher, K.; Millis, J.; Moriarty, P.; Mukherjee, R.; Nelson, T.; Nieto, D.; de Bhróithe, A. O'Faoláin; Ong, R. A.; Otte, A. N.; Park, N.; Perkins, J. S.; Pohl, M.; Popkow, A.; Prokoph, H.; Quinn, J.; Ragan, K.; Rajotte, J.; Reyes, L. C.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Sadun, A.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Sheidaei, F.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Theiling, M.; Tyler, J.; Varlotta, A.; Vassiliev, V. V.; Vincent, S.; Wakely, S. P.; Weekes, T. C.; Weinstein, A.; Welsing, R.; Wilhelm, A.; Williams, D. A.; Zitzer, and B.; Böttcher, M.; Fumagalli, M.

    2014-12-03

    We summarize broadband observations of the TeV-emitting blazar 1ES 1959 650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift UVOT, X-ray observations by the Swift X-ray Telescope, high-energy gamma-ray observations with the Fermi Large Area Telescope, and very-high-energy (VHE) gamma-ray observations by VERITAS above 315 GeV, all taken between 2012 April 17 and 2012 June 1 (MJD 56034 and 56079). The contemporaneous variability of the broadband spectral energy distribution is explored in the context of a simple synchrotron self Compton (SSC) model. In the SSC emission scenario, we find that the parameters required to represent the high state are significantly different than those in the low state. Motivated by possible evidence of gas in the vicinity of the blazar, we also investigate a reflected emission model to describe the observed variability pattern. This model assumes that the non-thermal emission from the jet is reflected by a nearby cloud of gas, allowing the reflected emission to re-enter the blob and produce an elevated gamma-ray state with no simultaneous elevated synchrotron flux. The model applied here, although not required to explain the observed variability pattern, represents one possible scenario which can describe the observations. As applied to an elevated VHE state of 66% of the Crab Nebula flux, observed on a single night during the observation period, the reflected emission scenario does not support a purely leptonic non-thermal emission mechanism. The reflected model does, however, predict a reflected photon field with sufficient energy to enable elevated gamma-ray emission via pion production with protons of energies between 10 and 100 TeV.

  1. Investigating broadband variability of the TeV blazar 1ES 1959+650

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Barnacka, A.; Beilicke, M.; Benbow, W.; Berger, K.; Bird, R.; Bouvier, A.; et al

    2014-12-03

    We summarize broadband observations of the TeV-emitting blazar 1ES 1959 650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift UVOT, X-ray observations by the Swift X-ray Telescope, high-energy gamma-ray observations with the Fermi Large Area Telescope, and very-high-energy (VHE) gamma-ray observations by VERITAS above 315 GeV, all taken between 2012 April 17 and 2012 June 1 (MJD 56034 and 56079). The contemporaneous variability of the broadband spectral energy distribution is explored in the context of a simple synchrotron self Compton (SSC) model. In the SSC emission scenario, we find that the parameters requiredmore » to represent the high state are significantly different than those in the low state. Motivated by possible evidence of gas in the vicinity of the blazar, we also investigate a reflected emission model to describe the observed variability pattern. This model assumes that the non-thermal emission from the jet is reflected by a nearby cloud of gas, allowing the reflected emission to re-enter the blob and produce an elevated gamma-ray state with no simultaneous elevated synchrotron flux. The model applied here, although not required to explain the observed variability pattern, represents one possible scenario which can describe the observations. As applied to an elevated VHE state of 66% of the Crab Nebula flux, observed on a single night during the observation period, the reflected emission scenario does not support a purely leptonic non-thermal emission mechanism. The reflected model does, however, predict a reflected photon field with sufficient energy to enable elevated gamma-ray emission via pion production with protons of energies between 10 and 100 TeV.« less

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

    SciTech Connect (OSTI)

    Groh, J. H.; Damineli, A.; Moises, A. P.; Teodoro, M.; Hillier, D. J.; Barba, R.; Fernandez-Lajus, E.; Gamen, R. C.; Solivella, G.

    2009-11-01

    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.

  3. Assessment of Normal Variability in Peripheral Blood Gene Expression

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Campbell, Catherine; Vernon, Suzanne D.; Karem, Kevin L.; Nisenbaum, Rosane; Unger, Elizabeth R.

    2002-01-01

    Peripheral blood is representative of many systemic processes and is an ideal sample for expression profiling of diseases that have no known or accessible lesion. Peripheral blood is a complex mixture of cell types and some differences in peripheral blood gene expression may reflect the timing of sample collection rather than an underlying disease process. For this reason, it is important to assess study design factors that may cause variability in gene expression not related to what is being analyzed. Variation in the gene expression of circulating peripheral blood mononuclear cells (PBMCs) from three healthy volunteers sampled three times onemore » day each week for one month was examined for 1,176 genes printed on filter arrays. Less than 1% of the genes showed any variation in expression that was related to the time of collection, and none of the changes were noted in more than one individual. These results suggest that observed variation was due to experimental variability.« less

  4. MILLISECOND PULSAR AGES: IMPLICATIONS OF BINARY EVOLUTION AND A MAXIMUM SPIN LIMIT

    SciTech Connect (OSTI)

    Kiziltan, Buelent; Thorsett, Stephen E., E-mail: bulent@astro.ucsc.ed [Department of Astronomy and Astrophysics, University of California and UCO/Lick Observatory, Santa Cruz, CA 95064 (United States)

    2010-05-20

    In the absence of constraints from the binary companion or supernova remnant, the standard method for estimating pulsar ages is to infer an age from the rate of spin-down. While the generic spin-down age may give realistic estimates for normal pulsars, it can fail for pulsars with very short periods. Details of the spin-up process during the low-mass X-ray binary (LMXB) phase pose additional constraints on the period (P) and spin-down rates ( P-dot ) that may consequently affect the age estimate. Here, we propose a new recipe to estimate millisecond pulsar (MSP) ages that parametrically incorporates constraints arising from binary evolution and limiting physics. We show that the standard method can be improved by this approach to achieve age estimates closer to the true age while the standard spin-down age may overestimate or underestimate the age of the pulsar by more than a factor of {approx}10 in the millisecond regime. We use this approach to analyze the population on a broader scale. For instance, in order to understand the dominant energy loss mechanism after the onset of radio emission, we test for a range of plausible braking indices. We find that a braking index of n = 3 is consistent with the observed MSP population. We demonstrate the existence and quantify the potential contributions of two main sources of age corruption: the previously known 'age bias' due to secular acceleration and 'age contamination' driven by sub-Eddington progenitor accretion rates. We explicitly show that descendants of LMXBs that have accreted at very low rates ( m-dot << M-dot{sub Edd}) will exhibit ages that appear older than the age of the Galaxy. We further elaborate on this technique, the implications and potential solutions it offers regarding MSP evolution, the underlying age distribution, and the post-accretion energy loss mechanism.

  5. Nova-like cataclysmic variables in the infrared

    SciTech Connect (OSTI)

    Hoard, D. W.; Long, Knox S.; Howell, Steve B.; Wachter, Stefanie; Brinkworth, Carolyn S.; Knigge, Christian; Drew, J. E.; Szkody, Paula; Kafka, S.; Belle, Kunegunda; Ciardi, David R.; Froning, Cynthia S.; Van Belle, Gerard T.; Pretorius, M. L.

    2014-05-01

    Nova-like (NL) cataclysmic variables have persistently high mass transfer rates and prominent steady state accretion disks. We present an analysis of infrared observations of 12 NLs obtained from the Two Micron All Sky Survey, the Spitzer Space Telescope, and the Wide-field Infrared Survey Explorer All Sky Survey. The presence of an infrared excess at ? ? 3-5 ?m over the expectation of a theoretical steady state accretion disk is ubiquitous in our sample. The strength of the infrared excess is not correlated with orbital period, but shows a statistically significant correlation (but shallow trend) with system inclination that might be partially (but not completely) linked to the increasing view of the cooler outer accretion disk and disk rim at higher inclinations. We discuss the possible origin of the infrared excess in terms of emission from bremsstrahlung or circumbinary dust, with either mechanism facilitated by the mass outflows (e.g., disk wind/corona, accretion stream overflow, and so on) present in NLs. Our comparison of the relative advantages and disadvantages of either mechanism for explaining the observations suggests that the situation is rather ambiguous, largely circumstantial, and in need of stricter observational constraints.

  6. VARIABILITY OF DISK EMISSION IN PRE-MAIN SEQUENCE AND RELATED STARS. III. EXPLORING STRUCTURAL CHANGES IN THE PRE-TRANSITIONAL DISK IN HD169142

    SciTech Connect (OSTI)

    Wagner, Kevin R.; Sitko, Michael L.; Swearingen, Jeremy R.; Champney, Elizabeth H.; Johnson, Alexa N.; Werren, Chelsea; Grady, Carol A.; Whitney, Barbara A.; Russell, Ray W.; Schneider, Glenn H.; Momose, Munetake; Muto, Takayuki; Inoue, Akio K.; Lauroesch, James T.; Hornbeck, Jeremy; Brown, Alexander; Fukagawa, Misato; Currie, Thayne M.; Wisniewski, John P.; Woodgate, Bruce E. E-mail: sitkoml@ucmail.uc.edu E-mail: ehchampney@gmail.com E-mail: ccwerren@yahoo.com E-mail: bwhitney@astro.wisc.edu

    2015-01-10

    We present near-IR (NIR) and far-UV observations of the pre-transitional (gapped) disk in HD169142 using NASA's Infrared Telescope Facility and Hubble Space Telescope. The combination of our data along with existing data sets into the broadband spectral energy distribution reveals variability of up to 45% between ?1.5-10 ?m over a maximum timescale of 10yr. All observations known to us separate into two distinct states corresponding to a high near-IR state in the pre-2000 epoch and a low state in the post-2000 epoch, indicating activity within the ?1 AU region of the disk. Through analysis of the Pa ? and Br ? lines in our data we derive a mass accretion rate in 2013 May of M-dot ? (1.5-2.7) 10{sup 9} M {sub ?} yr{sup 1}. We present a theoretical modeling analysis of the disk in HD169142 using Monte-Carlo radiative transfer simulation software to explore the conditions and perhaps signs of planetary formation in our collection of 24yr of observations. We find that shifting the outer edge (r ? 0.3 AU) of the inner disk by 0.05 AU toward the star (in simulation of accretion and/or sculpting by forming planets) successfully reproduces the shift in NIR flux. We establish that the ?40-70 AU dark ring imaged in the NIR by Quanz et al. and Momose et al. and at 7mm by Osorio et al. may be reproduced with a 30% scaled density profile throughout the region, strengthening the link to this structure being dynamically cleared by one or more planetary mass bodies.

  7. Distant Observer - Energy Innovation Portal

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

    Solar Thermal Solar Thermal Energy Analysis Energy Analysis Find More Like This Return to Search Distant Observer Tool Quickly Identifies Costly Flaws in Concentrating Solar Power (CSP) Fields National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. The Distant Observer (DO) tool, developed by

  8. Engine having a variable valve actuation system

    DOE Patents [OSTI]

    Hefler, Gregory W. (Chillicothe, IL)

    2005-10-12

    An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

  9. Engine having a variable valve actuation system

    DOE Patents [OSTI]

    Hefler, Gregory W. (Chillicothe, IL)

    2004-10-12

    An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

  10. Variability in continuous traffic monitoring data

    SciTech Connect (OSTI)

    Wright, T.; Hu, P.S.; Young, J.

    1996-07-01

    Each state in the United States can be viewed as a universe of road segments. For each road segment in each state, it is desired to know various traffic characteristics based on count data, classification count data, and weigh-in-motion data. These data are absolutely essential for highway design, maintenance, safety, and planning. Given no cost constraints, each road segment would be continuously monitored every day of the year. However, in practice, a few road segments are monitored continuously every day of the year to produce annual characteristics of traffic flow. The remaining road segments are monitored for one or two days each year, and this resulting data are `adjusted` (using factors based on data collected from the continuously monitored road segments) to produce estimates of annual characteristics. With this general approach, each state strives to provide estimates of annual characteristics for each road segment within its jurisdiction. In 1985, the Federal Highway Administration (FHWA) published the Traffic Monitoring Guide to assist states in achieving this end. As with almost any data collection effort, the monitoring data suffers from errors from many sources. In this paper, we report some empirical findings in a research project sponsored by the FHWA. This research project studied the variability in the traffic data from the continuously monitored road segments from state(s) and, the extent to which this variability is transferred to and affects the precision of the data produced from the road segments which are monitored only one or two days each year. The ultimate hope is that states will eventually be able to not only publish an estimate of a characteristic such as Average Annual Daily Traffic (AADT) for each road segment, but also that each estimate will be accompanied by a statement expressing how good the estimate is in terms of its estimated variability or precision, which will likely be expressed as a coefficient of variation.

  11. Room at the Mountain: Estimated Maximum Amounts of Commercial Spent Nuclear Fuel Capable of Disposal in a Yucca Mountain Repository

    SciTech Connect (OSTI)

    Kessler, John H. [Electric Power Research Institute - EPRI, 3420 Hillview Avenue, Palo Alto, California 94304 (United States); Kemeny, John [University of Arizona, Tucson AZ 85721 (United States); King, Fraser [Integrity Corrosion Consulting, Ltd., 6732 Silverview Drive NW, Calgary, Alberta (Canada); Ross, Alan M. [Alan M. Ross and Associates, 1061 Gray Fox Circle Pleasanton, CA 94566 (Canada); Ross, Benjamen [Disposal Safety, Inc., Bethesda, MD 20814 (United States)

    2006-07-01

    The purpose of this paper is to present an initial analysis of the maximum amount of commercial spent nuclear fuel (CSNF) that could be emplaced into a geological repository at Yucca Mountain. This analysis identifies and uses programmatic, material, and geological constraints and factors that affect this estimation of maximum amount of CSNF for disposal. The conclusion of this initial analysis is that the current legislative limit on Yucca Mountain disposal capacity, 63,000 MTHM of CSNF, is a small fraction of the available physical capacity of the Yucca Mountain system assuming the current high-temperature operating mode (HTOM) design. EPRI is confident that at least four times the legislative limit for CSNF ({approx}260,000 MTHM) can be emplaced in the Yucca Mountain system. It is possible that with additional site characterization, upwards of nine times the legislative limit ({approx}570,000 MTHM) could be emplaced. (authors)

  12. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-09-08

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  13. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-08-25

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  14. Long-Term Wind Power Variability

    SciTech Connect (OSTI)

    Wan, Y. H.

    2012-01-01

    The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

  15. Crystal diffraction lens with variable focal length

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    1991-01-01

    A method and apparatus for altering the focal length of a focusing element o one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels.

  16. Crystal diffraction lens with variable focal length

    DOE Patents [OSTI]

    Smither, R.K.

    1991-04-02

    A method and apparatus for altering the focal length of a focusing element of one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities is disclosed. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels. 19 figures.

  17. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

    1998-01-01

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  18. Test report on the Abacus 30 kW bimode{reg_sign} inverter and maximum power tracker (MPT)

    SciTech Connect (OSTI)

    Bonn, R.; Ginn, J.; Zirzow, J.

    1995-06-01

    Sandia National Laboratories conducts the photovoltaic balance of systems (BOS) program, which is sponsored by the US Department of Energy`s Office of Energy Management. Under this program, SNL lets commercialization contracts and conducts a laboratory program designed to advance BOS technology, improve BOS component reliability, and reduce the BOS life-cycle-cost. This report details the testing of the first large US manufactured hybrid inverter and its associated maximum power tracker.

  19. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, Thomas F. (Denver, CO)

    1998-01-01

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  20. Variable temperature seat climate control system

    DOE Patents [OSTI]

    Karunasiri, Tissa R.; Gallup, David F.; Noles, David R.; Gregory, Christian T.

    1997-05-06

    A temperature climate control system comprises a variable temperature seat, at least one heat pump, at least one heat pump temperature sensor, and a controller. Each heat pump comprises a number of Peltier thermoelectric modules for temperature conditioning the air in a main heat exchanger and a main exchanger fan for passing the conditioned air from the main exchanger to the variable temperature seat. The Peltier modules and each main fan may be manually adjusted via a control switch or a control signal. Additionally, the temperature climate control system may comprise a number of additional temperature sensors to monitor the temperature of the ambient air surrounding the occupant as well as the temperature of the conditioned air directed to the occupant. The controller is configured to automatically regulate the operation of the Peltier modules and/or each main fan according to a temperature climate control logic designed both to maximize occupant comfort during normal operation, and minimize possible equipment damage, occupant discomfort, or occupant injury in the event of a heat pump malfunction.

  1. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, T.F.

    1998-09-29

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  2. WECC Variable Generation Planning Reference Book: Appendices

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-13

    The document titled “WECC Variable Generation Planning Reference Book”. This book is divided into two volumes; one is the main document (volume 1)and the other is appendices (volume 2). The main document is a collection of the best practices and the information regarding the application and impact of variables generation on power system planning. This volume (appendices) has additional information on the following topics: Probabilistic load flow problems. 2. Additional useful indices. 3. high-impact low-frequency (HILF) events. 4. Examples of wide-area nomograms. 5. Transmission line ratings, types of dynamic rating methods. 6. Relative costs per MW-km of different electric power transmission technologies. 7. Ultra-high voltage (UHV) transmission. 8.High voltage direct current (VSC-HVDC). 9. HVDC. 10. Rewiring of existing transmission lines. 11. High-temperature low sag (HTLS) conductors. 12. The direct method and energy functions for transient stability analysis in power systems. 13.Blackouts caused by voltage instability. 14. Algorithm for parameter continuation predictor-corrector methods. 15. Approximation techniques available for security regions. 16. Impacts of wind power on power system small signals stability. 17. FIDVR. 18. FACTS. 19. European planning standard and practices. 20. International experience in wind and solar energy sources. 21. Western Renewable Energy Zones (WREZ). 22. various energy storage technologies. 23. demand response. 24. BA consolidation and cooperation options. 25. generator power management requirements and 26. European planning guidelines.

  3. THE MICRO-ARCSECOND SCINTILLATION-INDUCED VARIABILITY (MASIV) SURVEY. III. OPTICAL IDENTIFICATIONS AND NEW REDSHIFTS

    SciTech Connect (OSTI)

    Pursimo, Tapio; Ojha, Roopesh; Rickett, Barney J.; Dutka, Michael S.; Koay, Jun Yi; Bignall, Hayley E.; Macquart, Jean-Pierre; Lovell, James E. J.; Kedziora-Chudczer, Lucyna

    2013-04-10

    Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Micro-Arcsecond Scintillation-Induced Variability) survey of 443 flat spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding that 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FSRQs and BL Lacs in the MASIV sample as these are the most compact object classes. We confirm that the level of IDV depends on the 5 GHz flux density for all optical spectral types. We find that BL Lac objects tend to be more variable than broad line quasars. The level of ISS decreases substantially above a redshift of about two. The decrease is found to be generally consistent with ISS expected for beamed emission from a jet that is limited to a fixed maximum brightness temperature in the source rest frame.

  4. SLUDGE BATCH VARIABILITY STUDY WITH FRIT 418

    SciTech Connect (OSTI)

    Johnson, F.; Edwards, T.

    2010-11-29

    The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO{sub 2} resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass regardless of thermal history. All of the normalized boron releases were less than 1 g/L. While all of the targeted glass compositions were predictable with respect to the Product Composition Control System (PCCS) models for durability, a small number of the measured glass compositions were located outside of the lower prediction limit indicating poorer durability than what was actually measured. These unpredictable glasses were in the same lithium metaborate (LM) preparation block during the chemical analyses, which resulted in measured compositions that were not representative of the target compositions. A review of the data did not indicate a clear cause for the problem. Re-digestion and re-measurement of three glasses from this preparation block yielded glass compositions closer to the target values and predicted PCT responses within the PCCS model uncertainty. Therefore, it is believed that the glasses were correctly fabricated and the targeted compositions are closer representations of the true compositions. Per the requirements of the DWPF Glass Product Control Program, the PCCS durability models have been shown to be applicable for the SB6/Frit 418 glass system. PCT results from the glasses fabricated as part of the variability study were shown to be predictable and/or acceptable with respect to the DWPF PCCS models. In addition, the inclusion of ThO{sub 2} was shown to have minimal impact on the acceptability and predictability of the variability study glasses.

  5. Difference image analysis of defocused observations with CSTAR

    SciTech Connect (OSTI)

    Oelkers, Ryan J.; Macri, Lucas M.; Wang, Lifan; Ashley, Michael C. B.; Lawrence, Jon S.; Luong-Van, Daniel; Cui, Xiangqun; Gong, Xuefei; Qiang, Liu; Yang, Huigen; Yuan, Xiangyan; Zhou, Xu; Feng, Long-Long; Zhu, Zhenxi; Pennypacker, Carl R.; York, Donald G.

    2015-02-01

    The Chinese Small Telescope ARray carried out high-cadence time-series observations of 27 square degrees centered on the South Celestial Pole during the Antarctic winter seasons of 20082010. Aperture photometry of the 2008 and 2010 i-band images resulted in the discovery of over 200 variable stars. Yearly servicing left the array defocused for the 2009 winter season, during which the system also suffered from intermittent frosting and power failures. Despite these technical issues, nearly 800,000 useful images were obtained using g, r, and clear filters. We developed a combination of difference imaging and aperture photometry to compensate for the highly crowded, blended, and defocused frames. We present details of this approach, which may be useful for the analysis of time-series data from other small-aperture telescopes regardless of their image quality. Using this approach, we were able to recover 68 previously known variables and detected variability in 37 additional objects. We also have determined the observing statistics for Dome A during the 2009 winter season; we find the extinction due to clouds to be less than 0.1 and 0.4 mag for 40% and 63% of the dark time, respectively.

  6. Role of Smarter Grids in Variable Renewable Resource Integration (Presentation)

    SciTech Connect (OSTI)

    Miller, M.

    2012-07-01

    This presentation discusses the role of smarter grids in variable renewable resource integration and references material from a forthcoming ISGAN issue paper: Smart Grid Contributions to Variable Renewable Resource Integration, co-written by the presenter and currently in review.

  7. Advanced Variable Speed Air-Source Integrated Heat Pump | Department...

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

    Pump Advanced Variable Speed Air-Source Integrated Heat Pump Advanced variable-speed Air Source Integrated Heat Pump prototype system and field test site near Knoxville, TN Credit: ...

  8. NERC Presentation: Accommodating High Levels of Variable Generation...

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

    Variable resources are types of electric power generation that rely on an uncontrolled, "variable" fuel (e.g. wind, sunlight, waves, tidal forces, and some types of rivers) to ...

  9. WECC Variable Generation Planning Reference Book

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-14

    This planning reference book is a document reflecting a Western Electricity Coordination Council (WECC) effort to put together multiple sources of information and provide a clear, systemic, comprehensive outline of the problems, both existing and anticipated; their impacts on the system; currently used and proposed solutions by the industry and research community; planning practices; new technologies, equipment, and standards; and expected future trends. This living (periodically updated) document could help WECC and other practicing engineers, especially the younger generation of engineers joining the workforce, to get familiar with a large variety of information related to the integration of variable resources into the WECC system, bypassing in part the need for time-consuming information gathering and learning processes from more experienced engineers or from the literature.

  10. Variable Speed Pumping: A Guide to Successful Applications - Executive

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

    Summary | Department of Energy Variable Speed Pumping: A Guide to Successful Applications - Executive Summary Variable Speed Pumping: A Guide to Successful Applications - Executive Summary This document describes the cost and energy savings potential of pumping system applications with variable duty requirements. PDF icon Variable Speed Pumping: A Guide to Successful Applications - Executive Summary (May 2004) More Documents & Publications Energy Conservation Program: Test Procedure for

  11. ELVIRA. Evaluation of Longitudinal Variabler in Relativistic Accelerators

    SciTech Connect (OSTI)

    Larson, D.J.

    1993-06-07

    ELVIRA is an encoding of an analytical formula to the calculation of longitudinal dynamics variable evolution during an accelerator ramp.

  12. Variable Speed Pumping: A Guide to Successful Applications; Executive Summary

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

    VARIABLE SPEED DRIVES A WAY TO LOWER LIFE CYCLE COSTS A GUIDE TO SUCCESSFUL APPLICATIONS A GUIDE TO SUCCESSFUL APPLICATIONS VARIABLE SPEED PUMPING VARIABLE SPEED PUMPING EXECUTIVE SUMMARY U.S. Department of Energy Energy Efficiency and Renewable Energy Industrial Technologies Program uropump VARIABLE SPEED DRIVES A WAY TO LOWER LIFE CYCLE COSTS Bringing you a prosperous future where energy is clean, abundant, reliable, and affordable Table of Contents Introduction . . . . . . . . . . . . . . . .

  13. NERC Presentation: Accommodating High Levels of Variable Generation,

    Office of Environmental Management (EM)

    October 29, 2010 | Department of Energy NERC Presentation: Accommodating High Levels of Variable Generation, October 29, 2010 NERC Presentation: Accommodating High Levels of Variable Generation, October 29, 2010 North American Electric Reliability Corporation (NERC) presentation to the Electricity Advisory Committee, October 29, 2010, on accommodating high levels of variable electricity eneration. Variable resources are types of electric power generation that rely on an uncontrolled,

  14. ARM - Publications: Science Team Meeting Documents: Observations...

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

    The potential for quantifying the natural variability in cloud characteristics at Pt. Reyes, California though the first deployment of the ARM Mobile Facility will be discussed....

  15. The RR Lyrae variable population in the Phoenix dwarf galaxy

    SciTech Connect (OSTI)

    Ordoez, Antonio J.; Sarajedini, Ata [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Yang, Soung-Chul, E-mail: a.ordonez@ufl.edu, E-mail: ata@astro.ufl.edu, E-mail: sczoo@kasi.re.kr [Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348 (Korea, Republic of)

    2014-05-10

    We present the first detailed study of the RR Lyrae variable population in the Local Group dSph/dIrr transition galaxy, Phoenix, using previously obtained HST/WFPC2 observations of the galaxy. We utilize template light curve fitting routines to obtain best fit light curves for RR Lyrae variables in Phoenix. Our technique has identified 78 highly probable RR Lyrae stars (54 ab-type; 24 c-type) with about 40 additional candidates. We find mean periods for the two populations of (P {sub ab}) = 0.60 0.03 days and (P{sub c} ) = 0.353 0.002 days. We use the properties of these light curves to extract, among other things, a metallicity distribution function for ab-type RR Lyrae. Our analysis yields a mean metallicity of ([Fe/H]) = 1.68 0.06 dex for the RRab stars. From the mean period and metallicity calculated from the ab-type RR Lyrae, we conclude that Phoenix is more likely of intermediate Oosterhoff type; however the morphology of the Bailey diagram for Phoenix RR Lyraes appears similar to that of an Oosterhoff type I system. Using the RRab stars, we also study the chemical enrichment law for Phoenix. We find that our metallicity distribution is reasonably well fitted by a closed-box model. The parameters of this model are compatible with the findings of Hidalgo et al., further supporting the idea that Phoenix appears to have been chemically enriched as a closed-box-like system during the early stage of its formation and evolution.

  16. Maximum mass of stable magnetized highly super-Chandrasekhar white dwarfs: stable solutions with varying magnetic fields

    SciTech Connect (OSTI)

    Das, Upasana; Mukhopadhyay, Banibrata E-mail: bm@physics.iisc.ernet.in

    2014-06-01

    We address the issue of stability of recently proposed significantly super-Chandrasekhar white dwarfs. We present stable solutions of magnetostatic equilibrium models for super-Chandrasekhar white dwarfs pertaining to various magnetic field profiles. This has been obtained by self-consistently including the effects of the magnetic pressure gradient and total magnetic density in a general relativistic framework. We estimate that the maximum stable mass of magnetized white dwarfs could be more than 3 solar mass. This is very useful to explain peculiar, overluminous type Ia supernovae which do not conform to the traditional Chandrasekhar mass-limit.

  17. Biomass Burning Observation Project Specifically,

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

    Burning Observation Project Specifically, the aircraft will obtain measurements of the microphysical, chemical, hygroscopic, and optical properties of aerosols. Data captured during BBOP will help scientists better understand how aerosols combine and change at a variety of distances and burn times. Locations Pasco, Washington. From July through September, the G-1 will be based out of its home base in Washington. From this location, it can intercept and measure smoke plumes from naturally

  18. Diffuse Shortwave Intensive Observation Period

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

    1 Diffuse Shortwave Intensive Observation Period The Diffuse Shortwave IOP ran from September 23 to October 12, 2001. During this IOP, Joe Michalsky (The State University of New York-Albany) and Tom Stoffel (National Renewable Energy Laboratory) deployed approximately 15 radiometers of various designs and manufacturers on the SGP Radiometer Calibration Facility. The purpose was to compare the accuracy of the radiometers for diffuse shortwave measurements. The Scripps Institution of Oceanography

  19. Intensive Observation Period Projects Scheduled

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

    1 Intensive Observation Period Projects Scheduled Several IOP projects have been scheduled for the SGP CART site this spring. These projects either have already begun or will begin shortly. Radiosondes The RS-90 Transition IOP is currently under way. The RS-90 model radiosonde is gradually replacing the older RS-80 model. Radiosondes are instrument packages attached to and launched by weather balloons. The instruments measure atmospheric pressure, temperature, and relative humidity as the

  20. ARM - Mobile Aerosol Observing System

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

    FacilitiesMobile Aerosol Observing System AMF Information Science Architecture Baseline Instruments AMF1 AMF2 AMF3 MAOS Data Operations AMF Fact Sheet Images Contacts AMF Deployments McMurdo Station, Antarctica, 2015-2016 Pearl Harbor, Hawaii, to San Francisco, California, 2015 Hyytiälä, Finland, 2014 Manacapuru, Brazil, 2014 Oliktok Point, Alaska, 2013 Los Angeles, California, to Honolulu, Hawaii, 2012 Cape Cod, Massachusetts, 2012 Gan Island, Maldives, 2011 Ganges Valley, India, 2011

  1. Observation of Nonlinear Compton Scattering

    SciTech Connect (OSTI)

    Kotseroglou, T.

    2003-12-19

    This experiment tests Quantum Electrodynamics in the strong field regime. Nonlinear Compton scattering has been observed during the interaction of a 46.6 GeV electron beam with a 10{sup 18} W/cm{sup 2} laser beam. The strength of the field achieved was measured by the parameter {eta} = e{var_epsilon}{sub rms}/{omega}mc = 0.6. Data were collected with infrared and green laser photons and circularly polarized laser light. The timing stabilization achieved between the picosecond laser and electron pulses has {sigma}{sub rms} = 2 ps. A strong signal of electrons that absorbed up to 4 infrared photons (or up to 3 green photons) at the same point in space and time, while emitting a single gamma ray, was observed. The energy spectra of the scattered electrons and the nonlinear dependence of the electron yield on the field strength agreed with the simulation over 3 orders of magnitude. The detector could not resolve the nonlinear Compton scattering from the multiple single Compton scattering which produced rates of scattered electrons of the same order of magnitude. Nevertheless, a simulation has studied this difference and concluded that the scattered electron rates observed could not be accounted for only by multiple ordinary Compton scattering; nonlinear Compton scattering processes are dominant for n {ge} 3.

  2. Category:Observation Wells | Open Energy Information

    Open Energy Info (EERE)

    Observation Wells Jump to: navigation, search Geothermalpower.jpg Looking for the Observation Wells page? For detailed information on Observation Wells, click here....

  3. A search for optical variability of type 2 quasars in SDSS stripe 82

    SciTech Connect (OSTI)

    Barth, Aaron J.; Carson, Daniel J.; Voevodkin, Alexey

    2014-01-01

    Hundreds of Type 2 quasars have been identified in Sloan Digital Sky Survey (SDSS) data, and there is substantial evidence that they are generally galaxies with highly obscured central engines, in accord with unified models for active galactic nuclei (AGNs). A straightforward expectation of unified models is that highly obscured Type 2 AGNs should show little or no optical variability on timescales of days to years. As a test of this prediction, we have carried out a search for variability in Type 2 quasars in SDSS Stripe 82 using difference-imaging photometry. Starting with the Type 2 AGN catalogs of Zakamska et al. and Reyes et al., we find evidence of significant g-band variability in 17 out of 173 objects for which light curves could be measured from the Stripe 82 data. To determine the nature of this variability, we obtained new Keck spectropolarimetry observations for seven of these variable AGNs. The Keck data show that these objects have low continuum polarizations (p ? 1% in most cases) and all seven have broad H? and/or Mg II emission lines in their total (unpolarized) spectra, indicating that they should actually be classified as Type 1 AGNs. We conclude that the primary reason variability is found in the SDSS-selected Type 2 AGN samples is that these samples contain a small fraction of Type 1 AGNs as contaminants, and it is not necessary to invoke more exotic possible explanations such as a population of 'naked' or unobscured Type 2 quasars. Aside from misclassified Type 1 objects, the Type 2 quasars do not generally show detectable optical variability over the duration of the Stripe 82 survey.

  4. Control device of an infinitely variable transmission

    SciTech Connect (OSTI)

    Tanaka, H.

    1987-01-27

    An automatic control system is described for a toric type infinitely variable transmission of a running vehicle, the speed of which is changed by varying a gear ratio corresponding to a running mode of the vehicle selected by a driver. The transmission comprises coaxially disposed input and output shafts with input and output disks having toroidal surfaces and respectively secured to the input and output shafts, a traction roller engaged with the toroidal surfaces of the disks, and a trunnion rotatably supporting the traction roller on a rotary shaft. The trunnion is linearly movable in the direction of a pivot axis which is perpendicular to the rotary shaft of the traction roller and is pivotable around the pivot axis so that the gear ratio between the input shaft and the output shaft may be changed. The control system comprises: a hydraulic cylinder receiving an axial end of the trunnion; and a hydraulic circuit connecting the hydraulic cylinder with a hydraulic source, the hydraulic circuit including a solenoid valve. The valve has means for repeatedly opening and closing the valve at predetermined intervals and controlling hydraulic supply to the hydraulic cylinder and thereby controlling the linear movement of the trunnion in the direction of the pivot axis so as to vary the gear ratio.

  5. Observation of the Top Quark

    DOE R&D Accomplishments [OSTI]

    Kim, S. B.

    1995-08-01

    Top quark production is observed in{bar p}p collisions at{radical}s= 1.8 TeV at the Fermilab Tevatron. The Collider Detector at Fermilab (CDF) and D{O} observe signals consistent with t{bar t} to WWb{bar b}, but inconsistent with the background prediction by 4.8{sigma} (CDF), 4.6a (D{O}). Additional evidence for the top quark Is provided by a peak in the reconstructed mass distribution. The kinematic properties of the excess events are consistent with the top quark decay. They measure the top quark mass to be 176{plus_minus}8(stat.){plus_minus}10(sys.) GeV/c{sup 2} (CDF), 199{sub -21}{sup+19}(stat.){plus_minus}22(sys.) GeV/c{sup 2} (D{O}), and the t{bar t} production cross section to be 6.8{sub -2.4}{sup+3.6}pb (CDF), 6.4{plus_minus}2.2 pb (D{O}).

  6. Reduction in Energy Consumption & Variability in Steel Foundry Operations

    SciTech Connect (OSTI)

    Frank Peters

    2005-05-04

    This project worked to improve the efficiency of the steel casting industry by reducing the variability that occurs because of process and product variation. The project focused on the post shakeout operations since roughly half of the production costs are in this area. These improvements will reduce the amount of variability, making it easier to manage the operation and improve the competitiveness. The reduction in variability will also reduce the need for many rework operations, which will result in a direct reduction of energy usage, particularly by the reduction of repeated heat treatment operations. Further energy savings will be realized from the reduction of scrap and reduced handling. Field studies were conducted at ten steel foundries that represented the U.S. steel casting industry, for a total of over 100 weeks of production observation. These studies quantified the amount of variability, and looked toward determining the source. A focus of the data collected was the grinding operations since this is a major effort in the cleaning room, and it represents the overall casting quality. The grinding was divided into two categories, expected and unexpected. Expected grinding is that in which the location of the effort is known prior to making the casting, such as smoothing parting lines, gates, and riser contacts. Unexpected grinding, which was approximately 80% of the effort, was done to improve the surfaces at weld repair locations, to rectify burnt on sand, and other surface anomalies at random locations. Unexpected grinding represents about 80% of the grinding effort. By quantifying this effort, the project raised awareness within the industry and the industry is continuing to make improvements. The field studies showed that the amount of variation of grinding operations (normalized because of the diverse set of parts studied) was very consistent across the industry. The field studies identified several specific sources that individually contributed to large process variation. This indicates the need for ongoing monitoring of the process and system to quantify the effort being expended. A system to measure the grinding effort was investigated but did not prove to be successful. A weld wire counting system was shown to be very successful in tracking casting quality by monitoring the quantity of weld wire being expended on a per casting basis. Further use of such systems is highly recommended. The field studies showed that the visual inspection process for the casting surface was a potentially large source of process variation. Measurement system analysis studies were conducted at three steel casting producers. The tests measured the consistency of the inspectors in identifying the same surface anomalies. The repeatability (variation of the same operator inspecting the same casting) was found to be relatively consistent across the companies at about 60-70%. However, this is still are very large amount of variation. Reproducibility (variation of different operators inspecting the same casting) was worse, ranging between 20 to 80% at the three locations. This large amount of variation shows that there is a great opportunity for improvement. Falsely identifying anomalies for reworking will cause increased expense and energy consumption. This is particularly true if a weld repair and repeated heat treatment is required. However, not identifying an anomaly could also result in future rework processing, a customer return, or scrap. To help alleviate this problem, casting surface comparator plates were developed and distributed to the industry. These plates are very inexpensive which enables them to be provided to all those involved with casting surface quality, such as operators, inspectors, sales, and management.

  7. Aerosol Observing System (AOS) Handbook

    SciTech Connect (OSTI)

    Jefferson, A

    2011-01-17

    The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earths radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

  8. Comet tail formation: Giotto observations

    SciTech Connect (OSTI)

    Wilken, B.; Jockers, K.; Johnstone, A.; Coates, A.; Heath, J.; Formisano, V.; Amata, E.; Winningham, J.D.; Thomsen, M.; Bryant, D.A.

    1986-01-01

    The process of mass loading of the solar wind by cometary ions, which forms comet tails, has been observed throughout the coma of comet Halley. Three distinct regimes were found where the nature of the energy and momentum coupling between solar wind and cometary ions is different. Outside the bow shock, where there is little angular scattering of the freshly ionized particles, the coupling is described by the simple pickup trajectory and the energy is controlled by the angle between the flow and the magnetic field. Just inside the bow shock, there is considerable scattering accompanied by another acceleration process which raises some particle energies well above the straightforward pickup value. Finally, closer to the nucleus, the amount of scattering decreases and the coupling is once more controlled by the magnetic field direction. 4 refs., 3 figs.

  9. Basement Fill Model Evaluation of Maximum Radionuclide Concentrations for Initial Suite of Radionuclides. Zion Station Restoration Project

    SciTech Connect (OSTI)

    Sullivan, Terry

    2014-12-10

    ZionSolutions is in the process of decommissioning the Zion Nuclear Power Plant in order to establish a new water treatment plant. There is some residual radioactive particles from the plant which need to be brought down to levels so an individual who receives water from the new treatment plant does not receive a radioactive dose in excess of 25 mrem/y? as specified in 10 CFR 20 Subpart E. The objectives of this report are: (a) To present a simplified conceptual model for release from the buildings with residual subsurface structures that can be used to provide an upper bound on radionuclide concentrations in the fill material and the water in the interstitial spaces of the fill. (b) Provide maximum water concentrations and the corresponding amount of mass sorbed to the solid fill material that could occur in each building for use by ZSRP in selecting ROCs for detailed dose assessment calculations.

  10. Potential Impact of Adopting Maximum Technologies as Minimum Efficiency Performance Standards in the U.S. Residential Sector

    SciTech Connect (OSTI)

    Letschert, Virginie; Desroches, Louis-Benoit; McNeil, Michael; Saheb, Yamina

    2010-05-03

    The US Department of Energy (US DOE) has placed lighting and appliance standards at a very high priority of the U.S. energy policy. However, the maximum energy savings and CO2 emissions reduction achievable via minimum efficiency performance standards (MEPS) has not yet been fully characterized. The Bottom Up Energy Analysis System (BUENAS), first developed in 2007, is a global, generic, and modular tool designed to provide policy makers with estimates of potential impacts resulting from MEPS for a variety of products, at the international and/or regional level. Using the BUENAS framework, we estimated potential national energy savings and CO2 emissions mitigation in the US residential sector that would result from the most aggressive policy foreseeable: standards effective in 2014 set at the current maximum technology (Max Tech) available on the market. This represents the most likely characterization of what can be maximally achieved through MEPS in the US. The authors rely on the latest Technical Support Documents and Analytical Tools published by the U.S. Department of Energy as a source to determine appliance stock turnover and projected efficiency scenarios of what would occur in the absence of policy. In our analysis, national impacts are determined for the following end uses: lighting, television, refrigerator-freezers, central air conditioning, room air conditioning, residential furnaces, and water heating. The analyzed end uses cover approximately 65percent of site energy consumption in the residential sector (50percent of the electricity consumption and 80percent of the natural gas and LPG consumption). This paper uses this BUENAS methodology to calculate that energy savings from Max Tech for the U.S. residential sector products covered in this paper will reach an 18percent reduction in electricity demand compared to the base case and 11percent in Natural Gas and LPG consumption by 2030 The methodology results in reductions in CO2 emissions of a similar magnitude.

  11. Future warming patterns linked to today’s climate variability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dai, Aiguo

    2016-01-11

    The reliability of model projections of greenhouse gas (GHG)-induced future climate change is often assessed based on models’ ability to simulate the current climate, but there has been little evidence that connects the two. In fact, this practice has been questioned because the GHG-induced future climate change may involve additional physical processes that are not important for the current climate. Here I show that the spatial patterns of the GHG-induced future warming in the 21st century is highly correlated with the patterns of the year-to-year variations of surface air temperature for today’s climate, with areas of larger variations during 1950–1979more » having more GHG-induced warming in the 21st century in all climate models. Such a relationship also exists in other climate fields such as atmospheric water vapor, and it is evident in observed temperatures from 1950–2010. The results suggest that many physical processes may work similarly in producing the year-to-year climate variations in the current climate and the GHG-induced long-term changes in the 21st century in models and in the real world. Furthermore, they support the notion that models that simulate present-day climate variability better are likely to make more reliable predictions of future climate change.« less

  12. SEASAT altimeter determination of ocean current variability

    SciTech Connect (OSTI)

    Bernstein, R.L.; Born, G.H.; Whritner, R.H.

    1982-04-30

    Radar altimeters of great precision (roughly-equal10 cm), such as the one that flew on the SEASAT satellite, are capable of measuring the small oceanic height variations associated with geostrophic ocean currents. An experiment was concluded in the Kuroshio Current east of Japan, verifying this capability. Air-expendable bathythermographs (AXBT's) were dropped to coincide with the SEASAT subtract during flights on September 25 and October 5 and 13, 1978. Changes in surface dynamic height between flights were inferred from the AXBT data. They agreed generally to within +- 10 cm of height changes observed in the altimeter data.

  13. SPECTROSCOPY OF NEW AND POORLY KNOWN CATACLYSMIC VARIABLES IN THE KEPLER FIELD

    SciTech Connect (OSTI)

    Howell, Steve B.; Still, Martin; Everett, Mark E.; Seebode, Sally A.; Szkody, Paula; Wood, Matt; Ramsay, Gavin; Cannizzo, John

    2013-04-15

    The NASA Kepler mission has been in science operation since 2009 May and is providing high precision, high cadence light curves of over 150,000 targets. Prior to launch, nine cataclysmic variables were known to lie within Kepler's field of view. We present spectroscopy for seven systems, four of which were newly discovered since launch. All of the stars presented herein have been observed by, or are currently being observed by, the Kepler space telescope. Three historic systems and one new candidate could not be detected at their sky position and two candidates are called into question as to their true identity.

  14. Present and Future Modes of Low Frequency Climate Variability

    SciTech Connect (OSTI)

    Cane, Mark A.

    2014-02-20

    This project addressed area (1) of the FOA, Interaction of Climate Change and Low Frequency Modes of Natural Climate Variability. Our overarching objective is to detect, describe and understand the changes in low frequency variability between model simulations of the preindustrial climate and simulations of a doubled CO2 climate. The deliverables are a set of papers providing a dynamical characterization of interannual, decadal, and multidecadal variability in coupled models with attention to the changes in this low frequency variability between pre-industrial concentrations of greenhouse gases and a doubling of atmospheric concentrations of CO2. The principle mode of analysis, singular vector decomposition, is designed to advance our physical, mechanistic understanding. This study will include external natural variability due to solar and volcanic aerosol variations as well as variability internal to the climate system. An important byproduct is a set of analysis tools for estimating global singular vector structures from the archived output of model simulations.

  15. Radiograph and passive data analysis using mixed variable optimization

    Office of Scientific and Technical Information (OSTI)

    (Patent) | SciTech Connect Patent: Radiograph and passive data analysis using mixed variable optimization Citation Details In-Document Search Title: Radiograph and passive data analysis using mixed variable optimization Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography analysis. For example, certain embodiments perform radiographic analysis using mixed variable computation techniques. One exemplary system comprises a radiation

  16. Impact of Variable Valve Timing on Low Temperature Combustion | Department

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

    of Energy Variable Valve Timing on Low Temperature Combustion Impact of Variable Valve Timing on Low Temperature Combustion Documents effects of variable valve actuation in implementing low temperature combustion in production engine platform. PDF icon deer10_de_ojeda.pdf More Documents & Publications Low-Temperature Combustion Demonstrator for High-Efficiency Clean Combustion Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion Multicylinder Diesel Engine for Low

  17. Estimation and Control of Diesel Engine Processes Utilizing Variable Intake

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

    Valve Actuation | Department of Energy Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve Actuation Estimation and Control of Diesel Engine Processes Utilizing Variable Intake Valve Actuation Air handling system model for multi-cylinder variable geometry turbocharged diesel engine with cooled EGR and flexible intake valve actuation developed to capture dynamic effects of gas exchange actuators PDF icon deer12_kocher.pdf More Documents & Publications Slide

  18. Evaluation of Variable Compression Ratio on Energy Efficiency | Department

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

    of Energy Variable Compression Ratio on Energy Efficiency Evaluation of Variable Compression Ratio on Energy Efficiency Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. PDF icon p-16_szybist.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2015: High Efficiency VCR Engine with Variable Valve Actuation and New Supercharging Technology The Effects of Fuel Composition and

  19. Enabling High Efficiency Clean Combustion with Micro-Variable

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

    Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI | Department of Energy Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI Enabling High Efficiency Clean Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI Key characteristics of variable orifice fuel injector are described that will extend the operation maps of early PCCI combustion and enable dual-mode combustion over full operating maps. PDF icon deer08_hou.pdf

  20. Role of Environmental Variability in Evaluating Stressor Effects

    SciTech Connect (OSTI)

    Luoma, Samuel N.; Clements, Will; Dewitt, Ted; Gerritsen, Jeroen; Hatch, Audrey; Jepson, Paul; Reynoldson, Trefor; Thom, Ronald M.

    2001-12-03

    In this chapter, we discuss how environmental variability affects the exposure of organisms and ecological systems to stressors, and give guidance on how to understand influences of stressors. We consider the characteristics of environmental variability and issues relating to the measurement of environmental variation. We discuss how to select the optimal indicators of ecological response in a variable natural environment. Finally, we suggest some approaches to incorporate environmental variability into resource management. In all cases we employ examples and case studies throughout to illustrate principles.

  1. Control Strategies for Centrifugal Pumps with Variable Flow Rate...

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

    This tip sheet discusses control strategies for centrifugal pumps with variable flow rate requirements in pumping systems and includes installation considerations. PUMPING SYSTEMS ...

  2. A Variational Pro jection Operator for Mapping of Internal Variables...

    Office of Scientific and Technical Information (OSTI)

    Title: A Variational Pro jection Operator for Mapping of Internal Variables. Authors: Mota, Alejandro ; Sun, WaiChing ; Ostien, Jakob ; Foulk, James W., III ; Long, Kevin...

  3. Advanced Variable Speed Air-Source Integrated Heat Pump 2013...

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

    Pump 2013 Peer Review Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program ...

  4. Host Lipid and Temperature as Important Screening Variables for...

    Office of Scientific and Technical Information (OSTI)

    Host Lipid and Temperature as Important Screening Variables for Crystallizing Integral ... Citation Details In-Document Search Title: Host Lipid and Temperature as Important ...

  5. Control Strategies for Centrifugal Pumps with Variable Flow Rate Requirements

    Broader source: Energy.gov [DOE]

    This tip sheet discusses control strategies for centrifugal pumps with variable flow rate requirements in pumping systems and includes installation considerations.

  6. Promising Technology: Variable-Air-Volume Ventilation System

    Broader source: Energy.gov [DOE]

    Variable-air-volume (VAV) ventilation saves energy compared to a constant-air-volume (CAV) ventilation system, mainly by reducing energy consumption associated with fans.

  7. QUASAR OPTICAL VARIABILITY IN THE PALOMAR-QUEST SURVEY (Journal...

    Office of Scientific and Technical Information (OSTI)

    amplitude and optical luminosity, and measure the logarithmic decrease in variability amplitude to scale as the logarithm of the luminosity times 0.205 +- 0.002. Black ...

  8. Process for applying control variables having fractal structures

    DOE Patents [OSTI]

    Bullock, J.S. IV; Lawson, R.L.

    1996-01-23

    A process and apparatus are disclosed for the application of a control variable having a fractal structure to a body or process. The process of the present invention comprises the steps of generating a control variable having a fractal structure and applying the control variable to a body or process reacting in accordance with the control variable. The process is applicable to electroforming where first, second and successive pulsed-currents are applied to cause the deposition of material onto a substrate, such that the first pulsed-current, the second pulsed-current, and successive pulsed currents form a fractal pulsed-current waveform. 3 figs.

  9. Adaptation to Climate Variability and Change: A Guidance Manual...

    Open Energy Info (EERE)

    Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Adaptation to Climate...

  10. Initial testing of a variable-stroke Stirling engine

    SciTech Connect (OSTI)

    Thieme, L.G.

    1985-02-01

    In support of the US Department of Energy's Stirling Engine Highway Vehicle Systems Program, NASA Lewis Research Center is evaluating variable-stroke control for Stirling engines. The engine being tested is the Advenco Stirling engine; this engine was manufactured by Philips Research Laboratories of the Netherlands and uses a variable-angle swash-plate drive to achieve variable stroke operation. This report describes the engine, presents initial steady-state test data taken at Lewis, and describes a major drive system failure and subsequent modifications. Computer simulation results are presented to show potential part-load efficiency gains with variable-stroke control.

  11. Process for applying control variables having fractal structures

    DOE Patents [OSTI]

    Bullock, IV, Jonathan S. (Oak Ridge, TN); Lawson, Roger L. (Oliver Springs, TN)

    1996-01-01

    A process and apparatus for the application of a control variable having a fractal structure to a body or process. The process of the present invention comprises the steps of generating a control variable having a fractal structure and applying the control variable to a body or process reacting in accordance with the control variable. The process is applicable to electroforming where first, second and successive pulsed-currents are applied to cause the deposition of material onto a substrate, such that the first pulsed-current, the second pulsed-current, and successive pulsed currents form a fractal pulsed-current waveform.

  12. First-Principles Investigation of Nanopore Sequencing Using Variable...

    Office of Scientific and Technical Information (OSTI)

    First-Principles Investigation of Nanopore Sequencing Using Variable Voltage Bias on Graphene-Based Nanoribbons Citation Details In-Document Search Title: First-Principles...

  13. Sub-daily Statistical Downscaling of Meteorological Variables...

    Office of Scientific and Technical Information (OSTI)

    and variance that was accurate within 1% for all variables except atmospheric pressure, wind speed, and precipitation. Correlations between downscaled output and the expected...

  14. New photodisintegration threshold observable in

    SciTech Connect (OSTI)

    E.A. Wulf; R.S. Canon; Sally J. Gaff; J.H. Kelley; R.M. Prior; E.C. Schreiber; M. Spraker; D.R. Tilley; H.R. Weller; M. Viviani; A. Kievsky; S. Rosati; Rocco Schiavilla

    2000-02-01

    Measurements of the cross section, vector, and tensor analyzing powers, and linear gamma-ray polarization in the radiative capture reactions D(p,y){sup 3} He and p(d,y){sup 3}He at c.m. energies in the range 0-53 keV allow the determination of the reduced matrix elements (RMEs) relevant for these transitions. From these RMEs the value of the integral which determines the Gerasimov-Drell-Hearn sum rule for He is obtained in the threshold region, corresponding to two-body breakup, and compared with the results of an ab initio microscopic three-body model calculation.The theoretical predictions for the value of this integral based on a ''nucleons-only'' assumption are an order of magnitude smaller than experiment. The discrepancy is reduced to about a factor of 2 when two-body currents are taken into account. This factor of 2 is due to an almost exact cancellation between the dominant E1 RMEs in the theoretical calculation. The excess E1 strength observed experimentally could provide useful insights into the nuclear interaction at low energies.

  15. Resistance controllability and variability improvement in a TaO{sub x}-based resistive memory for multilevel storage application

    SciTech Connect (OSTI)

    Prakash, A. E-mail: amit.knp02@gmail.com Song, J.; Hwang, H. E-mail: amit.knp02@gmail.com; Deleruyelle, D.; Bocquet, M.

    2015-06-08

    In order to obtain reliable multilevel cell (MLC) characteristics, resistance controllability between the different resistance levels is required especially in resistive random access memory (RRAM), which is prone to resistance variability mainly due to its intrinsic random nature of defect generation and filament formation. In this study, we have thoroughly investigated the multilevel resistance variability in a TaO{sub x}-based nanoscale (<30?nm) RRAM operated in MLC mode. It is found that the resistance variability not only depends on the conductive filament size but also is a strong function of oxygen vacancy concentration in it. Based on the gained insights through experimental observations and simulation, it is suggested that forming thinner but denser conductive filament may greatly improve the temporal resistance variability even at low operation current despite the inherent stochastic nature of resistance switching process.

  16. Beam-beam observations in the Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Luo, Y.; Fischer, W.; White, S.

    2015-06-24

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has been operating since 2000. Over the past decade, thanks to the continuously increased bunch intensity and reduced β*s at the interaction points, the maximum peak luminosity in the polarized proton operation has been increased by more than two orders of magnitude. In this article, we first present the beam-beam observations in the previous RHIC polarized proton runs. Then we analyze the mechanisms for the beam loss and emittance growth in the presence of beam-beam interaction. The operational challenges and limitations imposed by beam-beam interaction and their remedies are also presented. In the end, we briefly introduce head-on beam-beam compensation with electron lenses in RHIC.

  17. Observation Targeting for the Tehachapi Pass and Mid-Columbia Basin: WindSENSE Phase III Project Summary Report

    SciTech Connect (OSTI)

    Hanley, D

    2011-10-22

    The overall goal of this multi-phased research project known as WindSENSE is to develop an observation system deployment strategy that would improve wind power generation forecasts. The objective of the deployment strategy is to produce the maximum benefit for 1- to 6-hour ahead forecasts of wind speed at hub-height ({approx}80 m). In Phase III of the project, the focus was on the Mid-Columbia Basin region which encompasses the Bonneville Power Administration (BPA) wind generation area shown in Figure 1 that includes Klondike, Stateline, and Hopkins Ridge wind plants. The typical hub height of a wind turbine is approximately 80-m above ground level (AGL). So it would seem that building meteorological towers in the region upwind of a wind generation facility would provide data necessary to improve the short-term forecasts for the 80-m AGL wind speed. However, this additional meteorological information typically does not significantly improve the accuracy of the 0- to 6-hour ahead wind power forecasts because processes controlling wind variability change from day-to-day and, at times, from hour-to-hour. It is also important to note that some processes causing significant changes in wind power production function principally in the vertical direction. These processes will not be detected by meteorological towers at off-site locations. For these reasons, it is quite challenging to determine the best type of sensors and deployment locations. To address the measurement deployment problem, Ensemble Sensitivity Analysis (ESA) was applied in the Phase I portion of the WindSENSE project. The ESA approach was initially designed to produce spatial fields that depict the sensitivity of a forecast metric to a set of prior state variables selected by the user. The best combination of variables and locations to improve the forecast was determined using the Multiple Observation Optimization Algorithm (MOOA) developed in Phase I. In Zack et al. (2010a), the ESA-MOOA approach was applied and evaluated for the wind plants in the Tehachapi Pass region for a period during the warm season. That research demonstrated that forecast sensitivity derived from the dataset was characterized by well-defined, localized patterns for a number of state variables such as the 80-m wind and the 25-m to 1-km temperature difference prior to the forecast time. The sensitivity patterns produced as part of the Tehachapi Pass study were coherent and consistent with the basic physical processes that drive wind patterns in the Tehachapi area. In Phase II of the WindSENSE project, the ESA-MOOA approach was extended and applied to the wind plants located in the Mid-Columbia Basin wind generation area of Washington-Oregon during the summer and to the Tehachapi Pass region during the winter. The objective of this study was to identify measurement locations and variables that have the greatest positive impact on the accuracy of wind forecasts in the 0- to 6-hour look-ahead periods for the two regions and to establish a higher level of confidence in ESA-MOOA for mesoscale applications. The detailed methodology and results are provided in separate technical reports listed in the publications section below. Ideally, the data assimilation scheme used in the Phase III experiments would have been based upon an ensemble Kalman filter (EnKF) that was similar to the ESA method used to diagnose the Mid-Columbia Basin sensitivity patterns in the previous studies. However, running an EnKF system at high resolution is impractical because of the very high computational cost. Thus, it was decided to use a three-dimensional variational (3DVAR) analysis scheme that is less computationally intensive. The objective of this task is to develop an observation system deployment strategy for the mid Columbia Basin (i.e. the BPA wind generation region) that is designed to produce the maximum benefit for 1- to 6-hour ahead forecasts of hub-height ({approx}80 m) wind speed with a focus on periods of large changes in wind speed. There are two tasks in the current project effort designed to validate

  18. THE SLUDGE BATCH 7A GLASS VARIABILITY STUDY WITH FRIT 418 AND FRIT 702

    SciTech Connect (OSTI)

    Peeler, D.; Edwards, T.

    2011-03-24

    The Defense Waste Processing Facility (DWPF) is preparing to initiate processing of Sludge Batch 7a (SB7a) in May 2011. To support qualification of SB7a, the Savannah River National Laboratory (SRNL) was requested to execute a variability study (VS) to assess the applicability of the current Product Composition Control System (PCCS) durability models for the Frit 418-SB7a compositional region of interest. The objective of this study was to demonstrate applicability of the current durability models to the SB7a compositional region of interest and acceptability of the SB7a glasses with respect to the Environmental Assessment (EA) glass in terms of durability as defined by the Product Consistency Test (PCT). To support programmatic objectives, twenty-eight SB7a glasses were selected based on the nominal sludge projections used to support the frit recommendation. Twenty-three of the SB7a VS glasses were based on the use of Frit 418, while 5 glasses were based on the use of Frit 702. Frit 702 was also identified as a viable candidate for SB7a, especially if SO{sub 4} concentrations are found to be higher than anticipated. Frit 702 has shown a higher SO{sub 4} retention capability as compared to Frit 418. With respect to acceptability, the PCT results of the SB7a-VS glasses are acceptable relative to the EA glass regardless of thermal history (quenched or canister centerline cooled) or compositional view (target or measured). More specifically, all of the SB7a glasses have normalized boron release values (NL [B]) less than 0.9 g/L as compared to the benchmark NL [B] value for EA of 16.695 g/L. With respect to the applicability of the current durability models to the SB7a VS compositional region of interest, all of the study glasses (based on target compositions) lie within the 95% confidence intervals of the model predictions. When model applicability is based on the measured compositions, all of the SB7a VS glasses are predictable with the exception of SB7aVS-02 and SB7aVS-06. Although the NL [B] values of these two glasses range from 0.66 to 0.73 g/L (considered very acceptable), the PCT responses are not considered predictable by the current durability models. The current durability models are conservative for these glasses since they are more durable than predicted by the models. These two glasses are extreme vertices (EV) based compositions coupled with Frit 418 at 36% WL and target the maximum Na{sub 2}O content (15.01 wt% Na{sub 2}O) of the SB7a VS glasses. Higher alkali glasses for which the model overpredicts the PCT response have been observed previously in the Sludge Batch 3 (SB3) Phase 1 VS and the Sludge Batch 6 (SB6) VS.

  19. GNEP Partners and Observers | Department of Energy

    Office of Environmental Management (EM)

    GNEP Partners and Observers GNEP Partners and Observers A list of GNEP partners and observers. PDF icon GNEP Partners and Observers More Documents & Publications Microsoft PowerPoint - GNEP PARTNERS CANDIDATE PARTNERS AND OBSERVERS.PPT Senior Delegation Officials From All GNEP Participants Meeting Materials: April 21, 2008

  20. Special Emphasis Observances | Department of Energy

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

    Diversity and Inclusion » Special Emphasis Observances Special Emphasis Observances The Energy Department celebrates special emphasis observances regularly, inviting guest speakers to highlight how the agency's mission benefits from diversity and inclusion. The Energy Department celebrates special emphasis observances regularly, inviting guest speakers to highlight how the agency's mission benefits from diversity and inclusion. The Department of Energy observes special days, weeks, and months

  1. Validation of a 4D-PET Maximum Intensity Projection for Delineation of an Internal Target Volume

    SciTech Connect (OSTI)

    Callahan, Jason; Kron, Tomas; Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne ; Schneider-Kolsky, Michal; Dunn, Leon; Thompson, Mick; Siva, Shankar; Aarons, Yolanda; Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne ; Binns, David; Hicks, Rodney J.; Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne

    2013-07-15

    Purpose: The delineation of internal target volumes (ITVs) in radiation therapy of lung tumors is currently performed by use of either free-breathing (FB) {sup 18}F-fluorodeoxyglucose-positron emission tomography-computed tomography (FDG-PET/CT) or 4-dimensional (4D)-CT maximum intensity projection (MIP). In this report we validate the use of 4D-PET-MIP for the delineation of target volumes in both a phantom and in patients. Methods and Materials: A phantom with 3 hollow spheres was prepared surrounded by air then water. The spheres and water background were filled with a mixture of {sup 18}F and radiographic contrast medium. A 4D-PET/CT scan was performed of the phantom while moving in 4 different breathing patterns using a programmable motion device. Nine patients with an FDG-avid lung tumor who underwent FB and 4D-PET/CT and >5 mm of tumor motion were included for analysis. The 3 spheres and patient lesions were contoured by 2 contouring methods (40% of maximum and PET edge) on the FB-PET, FB-CT, 4D-PET, 4D-PET-MIP, and 4D-CT-MIP. The concordance between the different contoured volumes was calculated using a Dice coefficient (DC). The difference in lung tumor volumes between FB-PET and 4D-PET volumes was also measured. Results: The average DC in the phantom using 40% and PET edge, respectively, was lowest for FB-PET/CT (DCAir = 0.72/0.67, DCBackground 0.63/0.62) and highest for 4D-PET/CT-MIP (DCAir = 0.84/0.83, DCBackground = 0.78/0.73). The average DC in the 9 patients using 40% and PET edge, respectively, was also lowest for FB-PET/CT (DC = 0.45/0.44) and highest for 4D-PET/CT-MIP (DC = 0.72/0.73). In the 9 lesions, the target volumes of the FB-PET using 40% and PET edge, respectively, were on average 40% and 45% smaller than the 4D-PET-MIP. Conclusion: A 4D-PET-MIP produces volumes with the highest concordance with 4D-CT-MIP across multiple breathing patterns and lesion sizes in both a phantom and among patients. Freebreathing PET/CT consistently underestimates ITV when compared with 4D PET/CT for a lesion affected by respiration.

  2. First observations of tracking clouds using scanning ARM cloud radars

    SciTech Connect (OSTI)

    Borque, Paloma; Giangrande, Scott; Kollias, Pavlos

    2014-12-01

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (first echo). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud field and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.

  3. First observations of tracking clouds using scanning ARM cloud radars

    SciTech Connect (OSTI)

    Borque, Paloma; Giangrande, Scott; Kollias, Pavlos

    2014-12-01

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (‘‘first echo’’). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud field and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.

  4. THE GALEX TIME DOMAIN SURVEY. I. SELECTION AND CLASSIFICATION OF OVER A THOUSAND ULTRAVIOLET VARIABLE SOURCES

    SciTech Connect (OSTI)

    Gezari, S.; Martin, D. C.; Forster, K.; Neill, J. D.; Morrissey, P.; Wyder, T. K.; Huber, M.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Magnier, E. A.; Tonry, J. L.; Heckman, T.; Bianchi, L.; Neff, S. G.; Seibert, M.; Schiminovich, D.; Price, P. A.

    2013-03-20

    We present the selection and classification of over a thousand ultraviolet (UV) variable sources discovered in {approx}40 deg{sup 2} of GALEX Time Domain Survey (TDS) NUV images observed with a cadence of 2 days and a baseline of observations of {approx}3 years. The GALEX TDS fields were designed to be in spatial and temporal coordination with the Pan-STARRS1 Medium Deep Survey, which provides deep optical imaging and simultaneous optical transient detections via image differencing. We characterize the GALEX photometric errors empirically as a function of mean magnitude, and select sources that vary at the 5{sigma} level in at least one epoch. We measure the statistical properties of the UV variability, including the structure function on timescales of days and years. We report classifications for the GALEX TDS sample using a combination of optical host colors and morphology, UV light curve characteristics, and matches to archival X-ray, and spectroscopy catalogs. We classify 62% of the sources as active galaxies (358 quasars and 305 active galactic nuclei), and 10% as variable stars (including 37 RR Lyrae, 53 M dwarf flare stars, and 2 cataclysmic variables). We detect a large-amplitude tail in the UV variability distribution for M-dwarf flare stars and RR Lyrae, reaching up to |{Delta}m| = 4.6 mag and 2.9 mag, respectively. The mean amplitude of the structure function for quasars on year timescales is five times larger than observed at optical wavelengths. The remaining unclassified sources include UV-bright extragalactic transients, two of which have been spectroscopically confirmed to be a young core-collapse supernova and a flare from the tidal disruption of a star by dormant supermassive black hole. We calculate a surface density for variable sources in the UV with NUV < 23 mag and |{Delta}m| > 0.2 mag of {approx}8.0, 7.7, and 1.8 deg{sup -2} for quasars, active galactic nuclei, and RR Lyrae stars, respectively. We also calculate a surface density rate in the UV for transient sources, using the effective survey time at the cadence appropriate to each class, of {approx}15 and 52 deg{sup -2} yr{sup -1} for M dwarfs and extragalactic transients, respectively.

  5. A monitoring campaign for Luhman 16AB. I. Detection of resolved near-infrared spectroscopic variability

    SciTech Connect (OSTI)

    Burgasser, Adam J.; Gillon, Michal; Jehin, E.; Delrez, L.; Opitom, C.; Faherty, Jacqueline K.; Radigan, Jacqueline; Triaud, Amaury H. M. J.; Plavchan, Peter

    2014-04-10

    We report resolved near-infrared spectroscopic monitoring of the nearby L dwarf/T dwarf binary WISE J104915.57531906.1AB (Luhman 16AB), as part of a broader campaign to characterize the spectral energy distribution and temporal variability of this system. A continuous 45 minute sequence of low-resolution IRTF/SpeX data spanning 0.8-2.4 ?m were obtained, concurrent with combined-light optical photometry with ESO/TRAPPIST. Our spectral observations confirm the flux reversal of this binary, and we detect a wavelength-dependent decline in the relative spectral fluxes of the two components coincident with a decline in the combined-light optical brightness of the system over the course of the observation. These data are successfully modeled as a combination of achromatic (brightness) and chromatic (color) variability in the T0.5 Luhman 16B, consistent with variations in overall cloud opacity; and no significant variability was found in L7.5 Luhman 16A, consistent with recent resolved photometric monitoring. We estimate a peak-to-peak amplitude of 13.5% at 1.25 ?m over the full light curve. Using a simple two-spot brightness temperature model for Luhman 16B, we infer an average cold covering fraction of ?30%-55%, varying by 15%-30% over a rotation period assuming a ?200-400 K difference between hot and cold regions. We interpret these variations as changes in the covering fraction of a high cloud deck and corresponding 'holes' which expose deeper, hotter cloud layers, although other physical interpretations are possible. A Rhines scale interpretation for the size of the variable features explains an apparent correlation between period and amplitude for Luhman 16B and the variable T dwarfs SIMP 0136+0933 and 2MASS J2139+0220, and predicts relatively fast winds (1-3 km s{sup 1}) for Luhman 16B consistent with light curve evolution on an advective time scale (1-3 rotation periods). The strong variability observed in this flux reversal brown dwarf pair supports the model of a patchy disruption of the mineral cloud layer as a universal feature of the L dwarf/T dwarf transition.

  6. Promising Technology: Magnetic Bearing Variable-Speed Centrifugal Chillers

    Broader source: Energy.gov [DOE]

    Magnetic bearing variable speed centrifugal chillers save energy compared to conventional chillers by eliminating friction with the magnetic bearings and by improving efficiency at partial loads with the variable speed drive. In addition to saving energy, the magnetic bearings eliminate the maintenance costs associated with lubricating conventional metal bearings.

  7. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene First Observation of Plasmarons in Graphene Print Wednesday, 30 June 2010 00:00 An international team of scientists performing...

  8. Dynamics of Molecular Clouds: Observations, Simulations, and...

    Office of Scientific and Technical Information (OSTI)

    Conference: Dynamics of Molecular Clouds: Observations, Simulations, and NIF Experiments Citation Details In-Document Search Title: Dynamics of Molecular Clouds: Observations,...

  9. Variable frequency iteration MPPT for resonant power converters

    DOE Patents [OSTI]

    Zhang, Qian; Bataresh, Issa; Chen, Lin

    2015-06-30

    A method of maximum power point tracking (MPPT) uses an MPPT algorithm to determine a switching frequency for a resonant power converter, including initializing by setting an initial boundary frequency range that is divided into initial frequency sub-ranges bounded by initial frequencies including an initial center frequency and first and second initial bounding frequencies. A first iteration includes measuring initial powers at the initial frequencies to determine a maximum power initial frequency that is used to set a first reduced frequency search range centered or bounded by the maximum power initial frequency including at least a first additional bounding frequency. A second iteration includes calculating first and second center frequencies by averaging adjacent frequent values in the first reduced frequency search range and measuring second power values at the first and second center frequencies. The switching frequency is determined from measured power values including the second power values.

  10. Market Designs for High Levels of Variable Generation: Preprint

    SciTech Connect (OSTI)

    Milligan, M.; Holttinen, H.; Kiviluoma, J.; Orths, A.; Lynch, M.; Soder, L.

    2014-10-01

    Variable renewable generation is increasing in penetration in modern power systems, leading to higher variability in the supply and price of electricity as well as lower average spot prices. This raises new challenges, particularly in ensuring sufficient capacity and flexibility from conventional technologies. Because the fixed costs and lifetimes of electricity generation investments are significant, designing markets and regulations that ensure the efficient integration of renewable generation is a significant challenge. This papers reviews the state of play of market designs for high levels of variable generation in the United States and Europe and considers new developments in both regions.

  11. Turbo-generator control with variable valve actuation

    DOE Patents [OSTI]

    Vuk, Carl T. (Denver, IA)

    2011-02-22

    An internal combustion engine incorporating a turbo-generator and one or more variably activated exhaust valves. The exhaust valves are adapted to variably release exhaust gases from a combustion cylinder during a combustion cycle to an exhaust system. The turbo-generator is adapted to receive exhaust gases from the exhaust system and rotationally harness energy therefrom to produce electrical power. A controller is adapted to command the exhaust valve to variably open in response to a desired output for the turbo-generator.

  12. Small solar wind transients: Stereo-A observations in 2009

    SciTech Connect (OSTI)

    Yu, W.; Farrugia, C. J.; Galvin, A. B.; Simunac, K. D. C.; Popecki, M. A.; Lugaz, N.; Kilpua, E. K. J.; Moestl, C.; Luhmann, J. G.; Opitz, A.; Sauvaud, J.-A.

    2013-06-13

    Year 2009 was the last year of a long and pronounced solar activity minimum. In this year the solar wind in the inner heliosphere was for 90% of the time slow (< 450 km s{sup -1}) and with a weaker magnetic field strength compared to the previous solar minimum 1995-1996. We choose this year to present the results of a systematic search for small solar wind transients (STs) observed by the STEREO-Ahead (ST-A) probe. The data are from the PLASTIC and IMPACT instrument suites. By 'small' we mean a duration from {approx}1 to 12 hours. The parameters we search for to identify STs are (i) the total field strength, (ii) the rotation of the magnetic field vector, (iii) its smoothness, (iv) proton temperature, (v) proton beta, and (vi) Alfven Mach number. We find 45 examples. The STs have an average duration of {approx}4 hours. Ensemble averages of key quantities are: (i) maximum B = 7.01 nT; (ii) proton {beta}= 0.18; (iii) proton thermal speed = 20.8 km s{sup -1}; and (iv) Alfven Mach number = 6.13. No distinctive feature is found in the pitch angle distributions of suprathermal electrons. Our statistical results are compared with those of STs observed near Earth by Wind during 2009.

  13. Variable speed pumping: A guide to successful applications - Executive summary

    SciTech Connect (OSTI)

    None, None

    2004-05-01

    This document is the result of a collaboration between the Hydraulic Institute, Europump, and the U.S. DOE Industrial Technologies Program, and describes the cost and energy savings potential of pumping applications with variable duty requirements.

  14. USING CLOUD CLASSIFICATION TO MODEL SOLAR VARIABILITY Matthew...

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

    and variability profile for the location. 11. REFERENCES 1 R. J. Broderick, J. E. Quiroz, M. J. Reno, A. Ellis, J. Smith, and R. Dugan, "Time Series Power Flow Analysis for...

  15. Study finds surprising variability in shape of Van Allen Belts

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

    Study finds surprising variability in shape of Van Allen Belts Study finds surprising variability in shape of Van Allen Belts Understanding the shape and size of the belts, which shrink and swell in response to magnetic storms coming from the sun, is crucial for protecting our technology in space. February 23, 2016 1. The traditional idea of the radiation belts includes a larger, more dynamic outer belt and a smaller, more stable inner belt with an empty slot region separating the two. However,

  16. Host Lipid and Temperature as Important Screening Variables for

    Office of Scientific and Technical Information (OSTI)

    Crystallizing Integral Membrane Proteins in Lipidic Mesophases. Trials with Diacylglycerol Kinase (Journal Article) | SciTech Connect Host Lipid and Temperature as Important Screening Variables for Crystallizing Integral Membrane Proteins in Lipidic Mesophases. Trials with Diacylglycerol Kinase Citation Details In-Document Search Title: Host Lipid and Temperature as Important Screening Variables for Crystallizing Integral Membrane Proteins in Lipidic Mesophases. Trials with Diacylglycerol

  17. Envera Variable Compression Ratio Engine (Technical Report) | SciTech

    Office of Scientific and Technical Information (OSTI)

    Connect Envera Variable Compression Ratio Engine Citation Details In-Document Search Title: Envera Variable Compression Ratio Engine × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and technology. A paper copy of this document is also available for sale to the

  18. Variable Speed Fan Retrofits for Computer Room Air Conditioners |

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

    Department of Energy Variable Speed Fan Retrofits for Computer Room Air Conditioners Variable Speed Fan Retrofits for Computer Room Air Conditioners Case study describes various concepts for more cost-effective cooling solutions in data centers, while keeping in mind that the reliability of computing systems and their respective cooling systems is always a key criterion. PDF icon dc_fancasestudy.pdf More Documents & Publications Wireless Sensors Improve Data Center Efficiency NSIDC Data

  19. Comparison of Parameterized Cloud Variability to ARM Data

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

    Comparison of Parameterized Cloud Variability to ARM Data S. A. Klein National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Laboratory Princeton, New Jersey J. R. Norris Scripps Institute of Oceanography University of California La Jolla, California Abstract Cloud parameterizations in large-scale models often try to predict the amount of sub-grid scale variability in cloud properties to address the significant non-linear effects of radiation and precipitation. Statistical

  20. Continuously variable transmissions: theory and practice (Technical Report)

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

    | SciTech Connect Continuously variable transmissions: theory and practice Citation Details In-Document Search Title: Continuously variable transmissions: theory and practice × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information resources in energy science and technology. A paper copy of this

  1. Variable Renewable Energy: a Regulatory Roadmap (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-10-01

    There is not a one-size-fits-all approach to the regulation of variable renewable energy (VRE), but international experience reveals many approaches that are proving successful. Drawing upon research and experiences from various international contexts, the 21st Century Power Partnership in conjunction with the Clean Energy Solutions Center and Clean Energy Regulators Initiative identified key issues and ideas that have emerged as variable deployment has grown. The Power Partnership research, published in 2014, identified four broad categories of regulatory issues.

  2. NREL: Transmission Grid Integration - Variability of Renewable Energy

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

    Sources Variability of Renewable Energy Sources Wind and solar energy are referred to as variable generation sources because their electricity production varies based on the availability of wind and sun. However, they are not the only source of variation in a power system. The demand for electricity, or load, also varies, and the power system was designed to handle that uncertainty. Short-term changes in load (over seconds or minutes) are generally small and caused by random events that

  3. Variable Voltage Substation Electric Fire and Emergency Response |

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

    Department of Energy Variable Voltage Substation Electric Fire and Emergency Response Variable Voltage Substation Electric Fire and Emergency Response Question from Participant: My question is from an emergency response perspective. It was stated that it took ~ ½ for electricians to de-energize the electrical components before firefighters were allowed in to fight the fire. This delay causes more damage to equipment and potential propagation of the fire. Is there not a "master"

  4. Efficient Thermally Variable Cooling System | Department of Energy

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

    Thermally Variable Cooling System Efficient Thermally Variable Cooling System Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. PDF icon p-07_fulton.pdf More Documents & Publications CX-003867: Categorical Exclusion Determination EA-1704: Final Environmental Assessment Light-Duty Reactivity Controlled Compression Ignition Drive Cycle Fuel Economy and Emissions Estimates

  5. Self-Referenced Continuous-Variable Quantum Key Distribution Protocol

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Self-Referenced Continuous-Variable Quantum Key Distribution Protocol Citation Details In-Document Search Title: Self-Referenced Continuous-Variable Quantum Key Distribution Protocol Authors: Soh, Daniel B. S. ; Brif, Constantin ; Coles, Patrick J. ; Lütkenhaus, Norbert ; Camacho, Ryan M. ; Urayama, Junji ; Sarovar, Mohan Publication Date: 2015-10-21 OSTI Identifier: 1224143 Grant/Contract Number: AC04-94AL85000 Type: Published Article Journal Name:

  6. Residential Cold Climate Heat Pump with Variable-Speed Technology |

    Energy Savers [EERE]

    Department of Energy Cold Climate Heat Pump with Variable-Speed Technology Residential Cold Climate Heat Pump with Variable-Speed Technology Purdue prototype system Purdue prototype system Unico concept prototype Unico concept prototype Purdue prototype system Unico concept prototype Lead Performer: Unico Systems - St. Louis, MO Partners: -- Oak Ridge National Laboratory - Oak Ridge, TN -- Purdue University - West Lafayette, IN -- Emerson Electric - St. Louis, MO -- Invention House - St.

  7. Bottling Electricity: Storage as a Strategic Tool for Managing Variability

    Energy Savers [EERE]

    and Capacity Concerns in the Modern Grid - EAC Report (December 2008) | Department of Energy Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid - EAC Report (December 2008) Bottling Electricity: Storage as a Strategic Tool for Managing Variability and Capacity Concerns in the Modern Grid - EAC Report (December 2008) The objectives of this report are to provide the Secretary of Energy with the Electricity Advisory Committee's

  8. Hydrogen-Assisted Fracture: Materials Testing and Variables Governing

    Office of Environmental Management (EM)

    Fracture | Department of Energy Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture SNL has 40+ years experience with effects of high-pressure hydrogen gas on materials PDF icon hpwgw_matresearch_somerday.pdf More Documents & Publications Mechanical Properties of Structural Steels in Hydrogen Materials Compatibility Properties, Behavior and Material Compatibility of Hydrogen, Natural

  9. Variable C : N : P stoichiometry of dissolved organic matter cycling in the Community Earth System Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Letscher, R. T.; Moore, J. K.; Teng, Y. -C.; Primeau, F.

    2014-06-16

    Dissolved organic matter (DOM) plays an important role in the ocean's biological carbon pump by providing an advective/mixing pathway for ~ 20% of export production. DOM is known to have a stoichiometry depleted in nitrogen (N) and phosphorus (P) compared to the particulate organic matter pool, a~fact that is often omitted from biogeochemical-ocean general circulation models. However the variable C : N : P stoichiometry of DOM becomes important when quantifying carbon export from the upper ocean and linking the nutrient cycles of N and P with that of carbon. Here we utilize recent advances in DOM observational data coveragemore » and offline tracer-modeling techniques to objectively constrain the variable production and remineralization rates of the DOM C / N / P pools in a simple biogeochemical-ocean model of DOM cycling. The optimized DOM cycling parameters are then incorporated within the Biogeochemical Elemental Cycling (BEC) component of the Community Earth System Model and validated against the compilation of marine DOM observations. The optimized BEC simulation including variable DOM C : N : P cycling was found to better reproduce the observed DOM spatial gradients than simulations that used the canonical Redfield ratio. Global annual average export of dissolved organic C, N, and P below 100 m was found to be 2.28 Pg C yr-1 (143 Tmol C yr-1), 16.4 Tmol N yr-1, and 1 Tmol P yr-1, respectively with an average export C : N : P stoichiometry of 225 : 19 : 1 for the semilabile (degradable) DOM pool. DOC export contributed ~ 25% of the combined organic C export to depths greater than 100 m.« less

  10. Solar flare impulsive phase emission observed with SDO/EVE

    SciTech Connect (OSTI)

    Kennedy, Michael B.; Milligan, Ryan O.; Mathioudakis, Mihalis; Keenan, Francis P., E-mail: mkennedy29@qub.ac.uk [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, University Road, Belfast BT7 1NN (United Kingdom)

    2013-12-10

    Differential emission measures (DEMs) during the impulsive phase of solar flares were constructed using observations from the EUV Variability Experiment (EVE) and the Markov-Chain Monte Carlo method. Emission lines from ions formed over the temperature range log T{sub e} = 5.8-7.2 allow the evolution of the DEM to be studied over a wide temperature range at 10 s cadence. The technique was applied to several M- and X-class flares, where impulsive phase EUV emission is observable in the disk-integrated EVE spectra from emission lines formed up to 3-4 MK and we use spatially unresolved EVE observations to infer the thermal structure of the emitting region. For the nine events studied, the DEMs exhibited a two-component distribution during the impulsive phase, a low-temperature component with peak temperature of 1-2 MK, and a broad high-temperature component from 7 to 30 MK. A bimodal high-temperature component is also found for several events, with peaks at 8 and 25 MK during the impulsive phase. The origin of the emission was verified using Atmospheric Imaging Assembly images to be the flare ribbons and footpoints, indicating that the constructed DEMs represent the spatially average thermal structure of the chromospheric flare emission during the impulsive phase.

  11. Setting the renormalization scale in pQCD: Comparisons of the principle of maximum conformality with the sequential extended Brodsky-Lepage-Mackenzie approach

    SciTech Connect (OSTI)

    Ma, Hong -Hao; Wu, Xing -Gang; Ma, Yang; Brodsky, Stanley J.; Mojaza, Matin

    2015-05-26

    A key problem in making precise perturbative QCD (pQCD) predictions is how to set the renormalization scale of the running coupling unambiguously at each finite order. The elimination of the uncertainty in setting the renormalization scale in pQCD will greatly increase the precision of collider tests of the Standard Model and the sensitivity to new phenomena. Renormalization group invariance requires that predictions for observables must also be independent on the choice of the renormalization scheme. The well-known Brodsky-Lepage-Mackenzie (BLM) approach cannot be easily extended beyond next-to-next-to-leading order of pQCD. Several suggestions have been proposed to extend the BLM approach to all orders. In this paper we discuss two distinct methods. One is based on the Principle of Maximum Conformality (PMC), which provides a systematic all-orders method to eliminate the scale and scheme ambiguities of pQCD. The PMC extends the BLM procedure to all orders using renormalization group methods; as an outcome, it significantly improves the pQCD convergence by eliminating renormalon divergences. An alternative method is the sequential extended BLM (seBLM) approach, which has been primarily designed to improve the convergence of pQCD series. The seBLM, as originally proposed, introduces auxiliary fields and follows the pattern of the ?0-expansion to fix the renormalization scale. However, the seBLM requires a recomputation of pQCD amplitudes including the auxiliary fields; due to the limited availability of calculations using these auxiliary fields, the seBLM has only been applied to a few processes at low orders. In order to avoid the complications of adding extra fields, we propose a modified version of seBLM which allows us to apply this method to higher orders. As a result, we then perform detailed numerical comparisons of the two alternative scale-setting approaches by investigating their predictions for the annihilation cross section ratio Re+e at four-loop order in pQCD.

  12. First observations of tracking clouds using scanning ARM cloud radars

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Borque, Paloma; Giangrande, Scott; Kollias, Pavlos

    2014-12-01

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (‘‘first echo’’). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud fieldmore » and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.« less

  13. Crystal Structure of Neurotropism-Associated Variable Surface Protein 1 (VSP1) of Borrelia Turicatae

    SciTech Connect (OSTI)

    Lawson,C.; Yung, B.; Barbour, A.; Zuckert, W.

    2006-01-01

    Vsp surface lipoproteins are serotype-defining antigens of relapsing fever spirochetes that undergo multiphasic antigenic variation to allow bacterial persistence in spite of an immune response. Two isogenic serotypes of Borrelia turicatae strain Oz1 differ in their Vsp sequences and in disease manifestations in infected mice: Vsp1 is associated with the selection of a neurological niche, while Vsp2 is associated with blood and skin infection. We report here crystal structures of the Vsp1 dimer at 2.7 and 2.2 Angstroms. The structures confirm that relapsing fever Vsp proteins share a common helical fold with OspCs of Lyme disease-causing Borrelia. The fold features an inner stem formed by highly conserved N and C termini and an outer 'dome' formed by the variable central residues. Both Vsp1 and OspC structures possess small water-filled cavities, or pockets, that are lined largely by variable residues and are thus highly variable in shape. These features appear to signify tolerance of the Vsp-OspC fold for imperfect packing of residues at its antigenic surface. Structural comparison of Vsp1 with a homology model for Vsp2 suggests that observed differences in disease manifestation may arise in part from distinct differences in electrostatic surface properties; additional predicted positively charged surface patches on Vsp2 compared to Vsp1 may be sufficient to explain the relative propensity of Vsp2 to bind to acidic glycosaminoglycans.

  14. Young stellar object variability (YSOVAR): Long timescale variations in the mid-infrared

    SciTech Connect (OSTI)

    Rebull, L. M.; Cody, A. M.; Stauffer, J. R.; Morales-Caldern, M.; Carey, S. J.; Covey, K. R.; Gnther, H. M.; Poppenhaeger, K.; Wolk, S. J.; Hora, J. L.; Hillenbrand, L. A.; Plavchan, P.; Gutermuth, R.; Song, I.; Barrado, D.; Bayo, A.; James, D.; Vrba, F. J.; Alves de Oliveira, C.; Bouvier, J.; and others

    2014-11-01

    The YSOVAR (Young Stellar Object VARiability) Spitzer Space Telescope observing program obtained the first extensive mid-infrared (3.6 and 4.5 ?m) time series photometry of the Orion Nebula Cluster plus smaller footprints in 11 other star-forming cores (AFGL 490, NGC 1333, Mon R2, GGD 12-15, NGC 2264, L1688, Serpens Main, Serpens South, IRAS 20050+2720, IC 1396A, and Ceph C). There are ?29,000 unique objects with light curves in either or both IRAC channels in the YSOVAR data set. We present the data collection and reduction for the Spitzer and ancillary data, and define the 'standard sample' on which we calculate statistics, consisting of fast cadence data, with epochs roughly twice per day for ?40 days. We also define a 'standard sample of members' consisting of all the IR-selected members and X-ray-selected members. We characterize the standard sample in terms of other properties, such as spectral energy distribution shape. We use three mechanisms to identify variables in the fast cadence datathe Stetson index, a ?{sup 2} fit to a flat light curve, and significant periodicity. We also identified variables on the longest timescales possible of six to seven years by comparing measurements taken early in the Spitzer mission with the mean from our YSOVAR campaign. The fraction of members in each cluster that are variable on these longest timescales is a function of the ratio of Class I/total members in each cluster, such that clusters with a higher fraction of Class I objects also have a higher fraction of long-term variables. For objects with a YSOVAR-determined period and a [3.6]-[8] color, we find that a star with a longer period is more likely than those with shorter periods to have an IR excess. We do not find any evidence for variability that causes [3.6]-[4.5] excesses to appear or vanish within our data set; out of members and field objects combined, at most 0.02% may have transient IR excesses.

  15. Superconducting fault current-limiter with variable shunt impedance

    DOE Patents [OSTI]

    Llambes, Juan Carlos H; Xiong, Xuming

    2013-11-19

    A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

  16. Control of entity interactions in a hierarchical variable resolution simulation

    SciTech Connect (OSTI)

    Powell, D.R.

    1997-08-01

    There has long been interest in variable resolution modeling to support military analysis for a broad range of interest areas. Despite the ever-present desire for models of greater fidelity at the expense of analysis and computation resources, models of moderate to low fidelity are still required at many levels of decision-making. Problems can arise due to the issue of consistency among the family of models used for analysis. To address this and other problems, models of variable resolution have been suggested. However, such variable resolution architectures inherently carry their own set of issues which must be resolved in order to be useful. First, what are the structural requirements for a variable resolution model; and second, how are interactions between entities governed, especially when the entities have different resolutions? This paper addresses these issues and discusses key mechanisms needed to develop a variable resolution combat simulation that meets several core requirements for such models: seamless aggregation/disaggregation, appropriate interactions between entities of differing resolution, and control of the aggregation/disaggregation process.

  17. Control of entity interactions in a hierarchical variable resolution simulation

    SciTech Connect (OSTI)

    Powell, D.R.

    1997-10-01

    There has long been interest in variable resolution modeling to support military analysis for a broad range of interest areas. Despite the ever-present desire for models of greater fidelity at the expense of analysis and computation resources, models of moderate to low fidelity are still required at many levels of decision-making. Problems can arise due to the issue of consistency among the family of models used for analysis. To address this and other problems, models of variable resolution have been suggested. However, such variable resolution architectures inherently carry their own set of issues which must be resolved in order to be useful. First, what are the structural requirements for a variable resolution model; and second, how are interactions between entities governed, especially when the entities have different resolutions? This paper addresses these issues and discusses key mechanisms needed to develop a variable resolution combat simulation that meets several core requirements for such models: seamless aggregation/disaggregation, appropriate interactions between entities of differing resolution, and control of the aggregation/disaggregation process.

  18. EIS-0158: Supplemental Environmental Impact Statement to the 1979 Petroleum Production at Maximum Efficient Rate, Naval Petroleum Reserve No. 1(Elk Hills), Kern County, California (1993)

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this EIS to assess the potential environmental impacts of the continued operation of the Naval Petroleum Reserve No. 1 at the Maximum Efficient Rate authorized by Public Law 94-258. This EIS supplements DOE/EIS-0012.

  19. SENSITIVE SEARCH FOR RADIO VARIABLES AND TRANSIENTS IN THE EXTENDED CHANDRA DEEP FIELD SOUTH

    SciTech Connect (OSTI)

    Mooley, K. P.; Kulkarni, S. R.; Horesh, A.; Frail, D. A.; Ofek, E. O.; Miller, N. A.

    2013-05-10

    We report on an analysis of the Extended Chandra Deep Field South (E-CDFS) region using archival data from the Very Large Array, with the goal of studying radio variability and transients at the sub-milliJansky level. The 49 epochs of E-CDFS observations at 1.4 GHz sample timescales from 1 day to 3 months. We find that only a fraction (1%) of unresolved radio sources above 40 {mu}Jy are variable at the 4{sigma} level. There is no evidence that the fractional variability changes along with the known transition of radio-source populations below 1 mJy. Optical identifications of the sources show that the variable radio emission is associated with the central regions of an active galactic nucleus or a star-forming galaxy. After a detailed comparison of the efficacy of various source-finding algorithms, we use the best to carry out a transient search. No transients were found. This implies that the areal density of transients with peak flux density greater than 0.21 mJy is less than 0.37 deg{sup -2} (at a confidence level of 95%). This result is approximately an order of magnitude below the transient rate measured at 5 GHz by Bower et al. but it is consistent with more recent upper limits from Frail et al. Our findings suggest that the radio sky at 1.4 GHz is relatively quiet. For multi-wavelength transient searches, such as the electromagnetic counterparts to gravitational waves, this frequency may be optimal for reducing the high background of false positives.

  20. ACTIVE LEARNING TO OVERCOME SAMPLE SELECTION BIAS: APPLICATION TO PHOTOMETRIC VARIABLE STAR CLASSIFICATION

    SciTech Connect (OSTI)

    Richards, Joseph W.; Starr, Dan L.; Miller, Adam A.; Bloom, Joshua S.; Butler, Nathaniel R.; Berian James, J.; Brink, Henrik; Long, James P.; Rice, John

    2012-01-10

    Despite the great promise of machine-learning algorithms to classify and predict astrophysical parameters for the vast numbers of astrophysical sources and transients observed in large-scale surveys, the peculiarities of the training data often manifest as strongly biased predictions on the data of interest. Typically, training sets are derived from historical surveys of brighter, more nearby objects than those from more extensive, deeper surveys (testing data). This sample selection bias can cause catastrophic errors in predictions on the testing data because (1) standard assumptions for machine-learned model selection procedures break down and (2) dense regions of testing space might be completely devoid of training data. We explore possible remedies to sample selection bias, including importance weighting, co-training, and active learning (AL). We argue that AL-where the data whose inclusion in the training set would most improve predictions on the testing set are queried for manual follow-up-is an effective approach and is appropriate for many astronomical applications. For a variable star classification problem on a well-studied set of stars from Hipparcos and Optical Gravitational Lensing Experiment, AL is the optimal method in terms of error rate on the testing data, beating the off-the-shelf classifier by 3.4% and the other proposed methods by at least 3.0%. To aid with manual labeling of variable stars, we developed a Web interface which allows for easy light curve visualization and querying of external databases. Finally, we apply AL to classify variable stars in the All Sky Automated Survey, finding dramatic improvement in our agreement with the ASAS Catalog of Variable Stars, from 65.5% to 79.5%, and a significant increase in the classifier's average confidence for the testing set, from 14.6% to 42.9%, after a few AL iterations.

  1. Quantum simulation of quantum field theory using continuous variables

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Marshall, Kevin; Pooser, Raphael C.; Siopsis, George; Weedbrook, Christian

    2015-12-14

    Much progress has been made in the field of quantum computing using continuous variables over the last couple of years. This includes the generation of extremely large entangled cluster states (10,000 modes, in fact) as well as a fault tolerant architecture. This has lead to the point that continuous-variable quantum computing can indeed be thought of as a viable alternative for universal quantum computing. With that in mind, we present a new algorithm for continuous-variable quantum computers which gives an exponential speedup over the best known classical methods. Specifically, this relates to efficiently calculating the scattering amplitudes in scalar bosonicmore » quantum field theory, a problem that is known to be hard using a classical computer. Thus, we give an experimental implementation based on cluster states that is feasible with today's technology.« less

  2. Integration of Variable Generation and Cost-Causation (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-09-01

    Variable renewable energy generation sources, such as wind and solar energy, provide benefits such as reduced environmental impact, zero fuel consumption, and low and stable costs. Advances in both technologies can reduce capital costs and provide significant control capabilities. However, their variability and uncertainty - which change with weather conditions, time of day, and season - can cause an increase in power system operating costs compared to a fully controllable power plant. Although a number of studies have assessed integration costs, calculating them correctly is challenging because it is difficult to accurately develop a baseline scenario without variable generation that properly accounts for the energy value. It is also difficult to appropriately allocate costs given the complex, nonlinear interactions between resources and loads.

  3. Complete multiwavelength evolution of galactic black hole transients during outburst decay. II. Compact jets and X-ray variability properties

    SciTech Connect (OSTI)

    Diner, T.; Kalemci, E.; Tomsick, J. A.; Buxton, M. M.; Bailyn, C. D.

    2014-11-01

    We investigated the relation between compact jet emission and X-ray variability properties of all black hole transients with multiwavelength coverage during their outburst decays. We studied the evolution of all power spectral components (including low-frequency quasi-periodic oscillations; QPOs), and related this evolution to changes in jet properties tracked by radio and infrared observations. We grouped sources according to their tracks in the radio/X-ray luminosity relation and show that the standards show stronger broadband X-ray variability than outliers at a given X-ray luminosity when the compact jet turns on. This trend is consistent with the internal shock model and can be important for the understanding of the presence of tracks in the radio/X-ray luminosity relation. We also observed that the total and the QPO rms amplitudes increase together during the earlier part of the outburst decay, but after the compact jet turns, either the QPO disappears or its rms amplitude decreases significantly while the total rms amplitudes remain high. We discuss these results with a scenario including a variable corona and a non-variable disk with a mechanism for the QPO separate from the mechanism that creates broad components. Finally, we evaluated the timing predictions of the magnetically dominated accretion flow model that can explain the presence of tracks in the radio/X-ray luminosity relation.

  4. Measuring quasar variability with Pan-STARRS1 and SDSS

    SciTech Connect (OSTI)

    Morganson, E.; Rix, H.-W.; Schlafly, E. F.; Walter, F.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Magnier, E. A.; Morgan, J. S.; Tonry, J. L.; Green, P. J.; Marshall, P. J.; Price, P. A.

    2014-04-01

    We measure quasar variability using the Panoramic Survey Telescope and Rapid Response System 1 Survey (Pan-STARRS1 or PS1) and the Sloan Digital Sky Survey (SDSS) and establish a method of selecting quasars via their variability in 10{sup 4} deg{sup 2} surveys. We use 10{sup 5} spectroscopically confirmed quasars that have been well measured in both PS1 and SDSS and take advantage of the decadal timescales that separate SDSS measurements and PS1 measurements. A power law model fits the data well over the entire time range tested, 0.01-10 yr. Variability in the current PS1-SDSS data set can efficiently distinguish between quasars and nonvarying objects. It improves the purity of a griz quasar color cut from 4.1% to 48% while maintaining 67% completeness. Variability will be very effective at finding quasars in data sets with no u band and in redshift ranges where exclusively photometric selection is not efficient. We show that quasars' rest-frame ensemble variability, measured as a root mean squared in ? magnitudes, is consistent with V(z, L, t) = A {sub 0}(1 + z){sup 0.37}(L/L {sub 0}){sup 0.16}(t/1 yr){sup 0.246}, where L {sub 0} = 10{sup 46} erg s{sup 1} and A {sub 0} = 0.190, 0.162, 0.147, or 0.141 in the g {sub P1}, r {sub P1}, i {sub P1}, or z {sub P1}filter, respectively. We also fit across all four filters and obtain median variability as a function of z, L, and ? as V(z, L, ?, t) = 0.079(1 + z){sup 0.15}(L/L {sub 0}){sup 0.2}(?/1000 nm){sup 0.44}(t/1 yr){sup 0.246}.

  5. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1...

  6. Enterprise Assessments Operational Awareness Record of Observations...

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

    Site: Waste Isolation Pilot Plant (WIPP) Subject: Observations of the design and modification progress of ... with regards to the design process and not to any state or local ...

  7. Posters Ground-Based Radiometric Observations

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

    data have also complemented other remote sensors such as K-band cloud Doppler radar and Doppler lidar. In addition, radiometric observations compose a database of ground- truth...

  8. Radioactivity in Precipitation: Methods and Observations from...

    Office of Environmental Management (EM)

    Radioactivity in Precipitation: Methods & Observations from Savannah River Site Dennis Jackson P.E. & Timothy Jannik - Savannah River National Laboratory Teresa Eddy - Savannah...

  9. Report: Human Capital Discussion and Observations

    Office of Environmental Management (EM)

    Human Capital Discussion, Observations, and Recommendations August 24, 2006 Submitted by: Mr. A. James Barnes and Mr. Dennis Ferrigno Background: During the March 23-24, 2006 EMAB...

  10. EA-1964: National Ecological Observation Network (NEON)

    Broader source: Energy.gov [DOE]

    The National Science Foundation (NSF) prepared an EA that evaluated potential environmental impacts of the proposed National Ecological Observation Network (NEON), a continental-scale network of...

  11. Aircraft S-HIS Observations during MPACE

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

    Aircraft S-HIS Observations during MPACE DeSlover, Daniel University of Wisconsin Holz, Robert University of Wisconsin, CIMMS Turner, David University of Wisconsin-Madison...

  12. Dynamics of Molecular Clouds: Observations, Simulations, and...

    Office of Scientific and Technical Information (OSTI)

    Simulations, and NIF Experiments Citation Details In-Document Search Title: Dynamics of Molecular Clouds: Observations, Simulations, and NIF Experiments Authors: Kane, J ...

  13. Variable C : N : P stoichiometry of dissolved organic matter cycling in the Community Earth System Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Letscher, R. T.; Moore, J. K.; Teng, Y. -C.; Primeau, F.

    2015-01-12

    Dissolved organic matter (DOM) plays an important role in the ocean's biological carbon pump by providing an advective/mixing pathway for ~ 20% of export production. DOM is known to have a stoichiometry depleted in nitrogen (N) and phosphorus (P) compared to the particulate organic matter pool, a fact that is often omitted from biogeochemical ocean general circulation models. However the variable C : N : P stoichiometry of DOM becomes important when quantifying carbon export from the upper ocean and linking the nutrient cycles of N and P with that of carbon. Here we utilize recent advances in DOM observationalmore » data coverage and offline tracer-modeling techniques to objectively constrain the variable production and remineralization rates of the DOM C : N : P pools in a simple biogeochemical-ocean model of DOM cycling. The optimized DOM cycling parameters are then incorporated within the Biogeochemical Elemental Cycling (BEC) component of the Community Earth System Model (CESM) and validated against the compilation of marine DOM observations. The optimized BEC simulation including variable DOM C : N : P cycling was found to better reproduce the observed DOM spatial gradients than simulations that used the canonical Redfield ratio. Global annual average export of dissolved organic C, N, and P below 100 m was found to be 2.28 Pg C yr-1 (143 Tmol C yr-1, 16.4 Tmol N yr-1, and 1 Tmol P yr-1, respectively, with an average export C : N : P stoichiometry of 225 : 19 : 1 for the semilabile (degradable) DOM pool. Dissolved organic carbon (DOC) export contributed ~ 25% of the combined organic C export to depths greater than 100 m.« less

  14. Properties of M31. IV. Candidate luminous blue variables from PAndromeda

    SciTech Connect (OSTI)

    Lee, C.-H.; Seitz, S.; Kodric, M.; Riffeser, A.; Koppenhoefer, J.; Bender, R.; Snigula, J.; Hopp, U.; Gssl, C.; Bianchi, L.; Price, P. A.; Fraser, M.; Burgett, W.; Chambers, K. C.; Flewelling, H.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Draper, P. W.

    2014-04-10

    We perform a study on the optical and infrared photometric properties of known luminous blue variables (LBVs) in M31 using a sample of LBV candidates from the Local Group Galaxy Survey by Masset et al. We find that M31 LBV candidates show photometric variability ranging from 0.375 to 1.576 mag in r {sub P1} during a 3 yr time span observed by the Pan-STARRS 1 Andromeda survey (PAndromeda). Their near-infrared colors also follow the distribution of Galactic LBVs as shown by Oksala et al. We use these features as selection criteria to search for unknown LBV candidates in M31. We thus devise a method to search for candidate LBVs using both optical color from the Local Group Galaxy Survey and infrared color from the Two Micron All Sky Survey, as well as photometric variations observed by PAndromeda. We find four sources exhibiting common properties of known LBVs. These sources also exhibit UV emission as seen from Galaxy Evolution Explorer, which is one of the previously adopted methods of searching for LBV candidates. The locations of the LBVs are well aligned with M31 spiral arms as seen in UV light, suggesting that they are evolved stars at a young age given their high-mass nature. We compare these candidates with the latest Geneva evolutionary tracks, which show that our new M31 LBV candidates are massive, evolved stars with ages of 10-100 Myr.

  15. The Impact of Soil Sampling Errors on Variable Rate Fertilization

    SciTech Connect (OSTI)

    R. L. Hoskinson; R C. Rope; L G. Blackwood; R D. Lee; R K. Fink

    2004-07-01

    Variable rate fertilization of an agricultural field is done taking into account spatial variability in the soils characteristics. Most often, spatial variability in the soils fertility is the primary characteristic used to determine the differences in fertilizers applied from one point to the next. For several years the Idaho National Engineering and Environmental Laboratory (INEEL) has been developing a Decision Support System for Agriculture (DSS4Ag) to determine the economically optimum recipe of various fertilizers to apply at each site in a field, based on existing soil fertility at the site, predicted yield of the crop that would result (and a predicted harvest-time market price), and the current costs and compositions of the fertilizers to be applied. Typically, soil is sampled at selected points within a field, the soil samples are analyzed in a lab, and the lab-measured soil fertility of the point samples is used for spatial interpolation, in some statistical manner, to determine the soil fertility at all other points in the field. Then a decision tool determines the fertilizers to apply at each point. Our research was conducted to measure the impact on the variable rate fertilization recipe caused by variability in the measurement of the soils fertility at the sampling points. The variability could be laboratory analytical errors or errors from variation in the sample collection method. The results show that for many of the fertility parameters, laboratory measurement error variance exceeds the estimated variability of the fertility measure across grid locations. These errors resulted in DSS4Ag fertilizer recipe recommended application rates that differed by up to 138 pounds of urea per acre, with half the field differing by more than 57 pounds of urea per acre. For potash the difference in application rate was up to 895 pounds per acre and over half the field differed by more than 242 pounds of potash per acre. Urea and potash differences accounted for almost 87% of the cost difference. The sum of these differences could result in a $34 per acre cost difference for the fertilization. Because of these differences, better analysis or better sampling methods may need to be done, or more samples collected, to ensure that the soil measurements are truly representative of the fields spatial variability.

  16. Implementing the DC Mode in Cosmological Simulations with Supercomoving Variables

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gnedin, Nickolay Y; Kravtsov, Andrey V; Rudd, Douglas H

    2011-06-02

    As emphasized by previous studies, proper treatment of the density fluctuation on the fundamental scale of a cosmological simulation volume - the 'DC mode' - is critical for accurate modeling of spatial correlations on scales ~> 10% of simulation box size. We provide further illustration of the effects of the DC mode on the abundance of halos in small boxes and show that it is straightforward to incorporate this mode in cosmological codes that use the 'supercomoving' variables. The equations governing evolution of dark matter and baryons recast with these variables are particularly simple and include the expansion factor, andmorehence the effect of the DC mode, explicitly only in the Poisson equation.less

  17. Thermoelectric power generator for variable thermal power source

    DOE Patents [OSTI]

    Bell, Lon E; Crane, Douglas Todd

    2015-04-14

    Traditional power generation systems using thermoelectric power generators are designed to operate most efficiently for a single operating condition. The present invention provides a power generation system in which the characteristics of the thermoelectrics, the flow of the thermal power, and the operational characteristics of the power generator are monitored and controlled such that higher operation efficiencies and/or higher output powers can be maintained with variably thermal power input. Such a system is particularly beneficial in variable thermal power source systems, such as recovering power from the waste heat generated in the exhaust of combustion engines.

  18. Method and apparatus for conducting variable thickness vapor deposition

    DOE Patents [OSTI]

    Nesslage, G.V.

    1984-08-03

    A method of vapor depositing metal on a substrate in variable thickness comprises conducting the deposition continuously without interruption to avoid formation of grain boundaries. To achieve reduced deposition in specific regions a thin wire or ribbon blocking body is placed between source and substrate to partially block vapors from depositing in the region immediately below.

  19. Variable-energy drift-tube linear accelerator

    DOE Patents [OSTI]

    Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM); Potter, James M. (Los Alamos, NM); Stovall, James E. (Los Alamos, NM)

    1984-01-01

    A linear accelerator system includes a plurality of post-coupled drift-tubes wherein each post coupler is bistably positionable to either of two positions which result in different field distributions. With binary control over a plurality of post couplers, a significant accumlative effect in the resulting field distribution is achieved yielding a variable-energy drift-tube linear accelerator.

  20. On computing ``accurate'' derivatives of Equation-of-State variables

    SciTech Connect (OSTI)

    Shestakov, A. I.

    2015-12-11

    We analyze a log-log interpolant for 2D EOS lookups, where the EOS independent variables are, say, T and ?. If the data f (Ti, ?j) are in the form of a power law, even locally, the interpolant is exact.

  1. Methodology for testing metal detectors using variables test data

    SciTech Connect (OSTI)

    Spencer, D.D.; Murray, D.W.

    1993-08-01

    By extracting and analyzing measurement (variables) data from portal metal detectors whenever possible instead of the more typical ``alarm``/``no-alarm`` (attributes or binomial) data, we can be more informed about metal detector health with fewer tests. This testing methodology discussed in this report is an alternative to the typical binomial testing and in many ways is far superior.

  2. THE CLASSIFICATION OF KEPLER B-STAR VARIABLES

    SciTech Connect (OSTI)

    McNamara, Bernard J.; Jackiewicz, Jason; McKeever, Jean E-mail: jasonj@nmsu.edu

    2012-04-15

    The light curves of 252 B-star candidates in the Kepler database are analyzed in a similar fashion to that done by Balona et al. to further characterize B-star variability, increase the sample of variable B stars for future study, and to identify stars whose power spectra include particularly interesting features such as frequency groupings. Stars are classified as either constant light emitters, {beta} Cep stars, slowly pulsating B stars (SPBs), hybrid pulsators, binaries or stars whose light curves are dominated by rotation (Bin/Rot), hot subdwarfs, or white dwarfs. One-hundred stars in our sample were found to be either light constants or to be variable at a level of less than 0.02 mmag. We increase the number of candidate B-star variables found in the Kepler database by Balona et al. in the following fashion: {beta} Cep stars from 0 to 10, SPBs from eight to 54, hybrid pulsators from seven to 21, and Bin/Rot stars from 23 to 82. For comparison purposes, approximately 51 SPBs and six hybrids had been known prior to 2007. The number of {beta} Cep stars known prior to 2004 was 93. A secondary result of this study is the identification of an additional 11 pulsating white dwarf candidates, four of which possess frequency groupings.

  3. A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned...

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

    A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature ...

  4. Constraints on the atmospheric circulation and variability of the eccentric hot Jupiter XO-3b

    SciTech Connect (OSTI)

    Wong, Ian; Knutson, Heather A.; Cowan, Nicolas B.; Lewis, Nikole K.; Agol, Eric; Burrows, Adam; Deming, Drake; Fortney, Jonathan J.; Laughlin, Gregory; Fulton, Benjamin J.; Langton, Jonathan; Showman, Adam P.

    2014-10-20

    We report secondary eclipse photometry of the hot Jupiter XO-3b in the 4.5 ?m band taken with the Infrared Array Camera on the Spitzer Space Telescope. We measure individual eclipse depths and center of eclipse times for a total of 12 secondary eclipses. We fit these data simultaneously with two transits observed in the same band in order to obtain a global best-fit secondary eclipse depth of 0.1580% 0.0036% and a center of eclipse phase of 0.67004 0.00013. We assess the relative magnitude of variations in the dayside brightness of the planet by measuring the size of the residuals during ingress and egress from fitting the combined eclipse light curve with a uniform disk model and place an upper limit of 0.05%. The new secondary eclipse observations extend the total baseline from one and a half years to nearly three years, allowing us to place an upper limit on the periastron precession rate of 2.9 10{sup 3} deg day{sup 1} the tightest constraint to date on the periastron precession rate of a hot Jupiter. We use the new transit observations to calculate improved estimates for the system properties, including an updated orbital ephemeris. We also use the large number of secondary eclipses to obtain the most stringent limits to date on the orbit-to-orbit variability of an eccentric hot Jupiter and demonstrate the consistency of multiple-epoch Spitzer observations.

  5. A comparison of observables for solid-solid phase transitions

    SciTech Connect (OSTI)

    Smilowitz, Laura B [Los Alamos National Laboratory; Henson, Bryan F [Los Alamos National Laboratory; Romero, Jerry J [Los Alamos National Laboratory

    2009-01-01

    The study of solid-solid phase transformations is hindered by the difficulty of finding a volumetric probe to use as a progress variable. Solids are typically optically opaque and heterogeneous. Over the past several years, second harmonic generation (SHG) has been used as a kinetic probe for a solid-solid phase transition in which the initial and final phases have different symmetries. Bulk generation of SHG is allowed by symmetry only in noncentrosymmetric crystallographic space groups. For the organic energetic nitramine octahydro-1,3 ,5,7 -tetranitro-1,3 ,5,7 -tatrazocine (HMX), the beta phase is centro symmetric (space group P2{sub 1}/c) and the delta phase iS noncentrosymmetric (space group P6{sub 1}22) making SHG an extremely sensitive, essentially zero background probe of the phase change progress. We have used SHG as a tool to follow the progress of the transformation from beta to delta phase during the solid-solid transformation. However, kinetic models of the transformation derived using different observables from several other groups have differed, showing later onset for the phase change and faster progression to completion. In this work, we have intercompared several techniques to understand these differences. The three techniques discussed are second harmonic generation, Raman spectroscopy, and differential scanning calorimetry (DSC). The progress of the beta to delta phase transition in HMX observed with each of these different probes will be discussed and advantages and disadvantages of each technique described. This paper compares several different observables for use in measuring the kinetics of solid-solid phase transitions. Relative advantages and disadvantages for each technique are described and a direct comparison of results is made for the beta to delta polymorphic phase transition of the energetic nitramine, octahydro-1,3,5,7-tetranitro-1,3,5,7-tatrazocine.

  6. Verification of maximum radial power peaking factor due to insertion of FPM-LEU target in the core of RSG-GAS reactor

    SciTech Connect (OSTI)

    Setyawan, Daddy; Rohman, Budi

    2014-09-30

    Verification of Maximum Radial Power Peaking Factor due to insertion of FPM-LEU target in the core of RSG-GAS Reactor. Radial Power Peaking Factor in RSG-GAS Reactor is a very important parameter for the safety of RSG-GAS reactor during operation. Data of radial power peaking factor due to the insertion of Fission Product Molybdenum with Low Enriched Uranium (FPM-LEU) was reported by PRSG to BAPETEN through the Safety Analysis Report RSG-GAS for FPM-LEU target irradiation. In order to support the evaluation of the Safety Analysis Report incorporated in the submission, the assessment unit of BAPETEN is carrying out independent assessment in order to verify safety related parameters in the SAR including neutronic aspect. The work includes verification to the maximum radial power peaking factor change due to the insertion of FPM-LEU target in RSG-GAS Reactor by computational method using MCNP5and ORIGEN2. From the results of calculations, the new maximum value of the radial power peaking factor due to the insertion of FPM-LEU target is 1.27. The results of calculations in this study showed a smaller value than 1.4 the limit allowed in the SAR.

  7. First Direct Observation of Spinons and Holons

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

    check on the interpretation of the data-were not available. The current observations are direct and the results are unambiguous because they were obtained from a simple material...

  8. ARM - Field Campaign - Biomass Burning Observation Project -...

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

    govCampaignsBiomass Burning Observation Project - BBOP Campaign Links BBOP Website ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or...

  9. First Direct Observation of Spinons and Holons

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

    structure has remained elusive. Working at the ALS, a team of researchers from Korea, Japan, and the U.S. has now observed electron spin-charge separation in a one-dimensional...

  10. Observations and simulations improve space weather models

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

    Observations improve space weather models Observations and simulations improve space weather models Researchers used data from the Van Allen Probes to improve a three-dimensional model created by Los Alamos scientists called DREAM3D. June 25, 2014 NASA's Van Allen Probes sample the Earth's magnetosphere. NASA's Van Allen Probes sample the Earth's magnetosphere. The work demonstrated that DREAM3D accurately simulated the behavior of a complex and dynamic event in the radiation belt that was

  11. Observing AAPI Heritage Month | Department of Energy

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

    Observing AAPI Heritage Month Observing AAPI Heritage Month May 1, 2012 - 4:42pm Addthis Bill Valdez Bill Valdez Director of Workforce Management What are the key facts? President Obama has also appointed a historic number of highly qualified Asian Americans and Pacific Islanders to senior positions in his Administration Throughout May,the White House Initiative on Asian Americans and Pacific Islanders will be sharing the many ways in which the Obama Administration has helped the Asian American

  12. Observations and simulations improve space weather models

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

    Observations improve space weather models Observations and simulations improve space weather models Researchers used data from the Van Allen Probes to improve a three-dimensional model created by Los Alamos scientists called DREAM3D. June 25, 2014 NASA's Van Allen Probes sample the Earth's magnetosphere. NASA's Van Allen Probes sample the Earth's magnetosphere. The work demonstrated that DREAM3D accurately simulated the behavior of a complex and dynamic event in the radiation belt that was

  13. First Direct Observation of Spinons and Holons

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

    First Direct Observation of Spinons and Holons First Direct Observation of Spinons and Holons Print Wednesday, 30 August 2006 00:00 Spin and charge are inseparable traits of an electron, but in one-dimensional solids, a 40-year-old theory predicts their separation into "collective" modes-as independent excitation quanta called spinons and holons. Angle-resolved photoemission spectroscopy (ARPES) should provide the most direct evidence of this spin-charge separation, as the single

  14. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene First Observation of Plasmarons in Graphene Print Wednesday, 30 June 2010 00:00 An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were

  15. Continuous-variable quantum teleportation with non-Gaussian resources

    SciTech Connect (OSTI)

    Dell'Anno, F.; De Siena, S.; Albano, L.; Illuminati, F.

    2007-08-15

    We investigate continuous variable quantum teleportation using non-Gaussian states of the radiation field as entangled resources. We compare the performance of different classes of degaussified resources, including two-mode photon-added and two-mode photon-subtracted squeezed states. We then introduce a class of two-mode squeezed Bell-like states with one-parameter dependence for optimization. These states interpolate between and include as subcases different classes of degaussified resources. We show that optimized squeezed Bell-like resources yield a remarkable improvement in the fidelity of teleportation both for coherent and nonclassical input states. The investigation reveals that the optimal non-Gaussian resources for continuous variable teleportation are those that most closely realize the simultaneous maximization of the content of entanglement, the degree of affinity with the two-mode squeezed vacuum, and the, suitably measured, amount of non-Gaussianity.

  16. Analysis of a teetered, variable-speed rotor: final report

    SciTech Connect (OSTI)

    Weber, T.L.; Wilson, R.E.; Walker, S.N. . Dept. of Mechanical Engineering)

    1991-06-01

    A computer model of a horizontal axis wind turbine (HOOT) with four structural degrees of freedom has been derived and verified. The four degrees of freedom include flapwise motion of the blades, teeter motion, and variable rotor speed. Options for the variable rotor speed include synchronous, induction, and constant-tip speed generator models with either start, stop, or normal operations. Verification is made by comparison with analytical solutions and mean and cyclic ESI-80 data. The Veers full-field turbulence model is used as a wind input for a synchronous and induction generator test case during normal operation. As a result of the comparison, it is concluded that the computer model can be used to predict accurately mean and cyclic loads with a turbulent wind input. 47 refs., 19 figs.

  17. Variable-energy collimator for high-energy radiation

    DOE Patents [OSTI]

    Hill, R.A.

    1982-03-03

    An apparatus is disclosed providing a variable aperture energy beam collimator. A plurality of beam opaque blocks are in sliding interface edge contact to form a variable aperture. The blocks may be offset at the apex angle to provide a non-equilateral aperture. A plurality of collimator block assemblies may be employed for providing a channel defining a collimated beam. Adjacent assemblies are inverted front-to-back with respect to one another for preventing noncollimated ;energy from emergine from the apparatus. An adjustment mechanism comprises a cable attached to at least one block and a hand wheel mechanism for operating the cable. The blocks are supported by guide rods engaging slide brackets on the blocks. The guide rods are pivotally connected at each end to intermediate actuators supported on rotatable shafts to change the shape of the aperture. A divergent collimated beam may be obtained by adjusting the apertures of adjacent stages to be unequal.

  18. Diagnostic for two-mode variable valve activation device

    DOE Patents [OSTI]

    Fedewa, Andrew M

    2014-01-07

    A method is provided for diagnosing a multi-mode valve train device which selectively provides high lift and low lift to a combustion valve of an internal combustion engine having a camshaft phaser actuated by an electric motor. The method includes applying a variable electric current to the electric motor to achieve a desired camshaft phaser operational mode and commanding the multi-mode valve train device to a desired valve train device operational mode selected from a high lift mode and a low lift mode. The method also includes monitoring the variable electric current and calculating a first characteristic of the parameter. The method also includes comparing the calculated first characteristic against a predetermined value of the first characteristic measured when the multi-mode valve train device is known to be in the desired valve train device operational mode.

  19. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, C.M.

    1998-12-15

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine is described. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod. 8 figs.

  20. Variability in Measured Space Temperatures in 60 Homes

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

    Variability in Measured Space Temperatures in 60 Homes David Roberts National Renewable Energy Laboratory Kerylyn Lay EnerNOC (formerly of the National Renewable Energy Laboratory) Technical Report NREL/TP-5500-58059 March 2013 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401 303-275-3000 *

  1. Free piston variable-stroke linear-alternator generator

    DOE Patents [OSTI]

    Haaland, Carsten M. (Dadeville, AL)

    1998-01-01

    A free-piston variable stroke linear-alternator AC power generator for a combustion engine. An alternator mechanism and oscillator system generates AC current. The oscillation system includes two oscillation devices each having a combustion cylinder and a flying turnbuckle. The flying turnbuckle moves in accordance with the oscillation device. The alternator system is a linear alternator coupled between the two oscillation devices by a slotted connecting rod.

  2. Variable Speed Fan Retrofits for Computer Room Air Conditioners

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

    Variable-Speed Fan Retrofits for Computer-Room Air Conditioners Prepared for the U.S. Department of Energy Federal Energy Management Program Technology Case Study Bulletin By Lawrence Berkeley National Laboratory Steve Greenberg September 2013 2 Contacts Steve Greenberg Lawrence Berkeley National Laboratory One Cyclotron Road, 90R3111 Berkeley, California 94720 (510) 486-6971 segreenberg@lbl.gov For more information on FEMP, please contact: Will Lintner, P.E., CEM Federal Energy Management

  3. Correlation between human observer performance and model observer performance in differential phase contrast CT

    SciTech Connect (OSTI)

    Li, Ke; Garrett, John; Chen, Guang-Hong

    2013-11-15

    Purpose: With the recently expanding interest and developments in x-ray differential phase contrast CT (DPC-CT), the evaluation of its task-specific detection performance and comparison with the corresponding absorption CT under a given radiation dose constraint become increasingly important. Mathematical model observers are often used to quantify the performance of imaging systems, but their correlations with actual human observers need to be confirmed for each new imaging method. This work is an investigation of the effects of stochastic DPC-CT noise on the correlation of detection performance between model and human observers with signal-known-exactly (SKE) detection tasks.Methods: The detectabilities of different objects (five disks with different diameters and two breast lesion masses) embedded in an experimental DPC-CT noise background were assessed using both model and human observers. The detectability of the disk and lesion signals was then measured using five types of model observers including the prewhitening ideal observer, the nonprewhitening (NPW) observer, the nonprewhitening observer with eye filter and internal noise (NPWEi), the prewhitening observer with eye filter and internal noise (PWEi), and the channelized Hotelling observer (CHO). The same objects were also evaluated by four human observers using the two-alternative forced choice method. The results from the model observer experiment were quantitatively compared to the human observer results to assess the correlation between the two techniques.Results: The contrast-to-detail (CD) curve generated by the human observers for the disk-detection experiments shows that the required contrast to detect a disk is inversely proportional to the square root of the disk size. Based on the CD curves, the ideal and NPW observers tend to systematically overestimate the performance of the human observers. The NPWEi and PWEi observers did not predict human performance well either, as the slopes of their CD curves tended to be steeper. The CHO generated the best quantitative agreement with human observers with its CD curve overlapping with that of human observer. Statistical equivalence between CHO and humans can be claimed within 11% of the human observer results, including both the disk and lesion detection experiments.Conclusions: The model observer method can be used to accurately represent human observer performance with the stochastic DPC-CT noise for SKE tasks with sizes ranging from 8 to 128 pixels. The incorporation of the anatomical noise remains to be studied.

  4. Simulating solar power plant variability : a review of current methods.

    SciTech Connect (OSTI)

    Lave, Matthew; Ellis, Abraham; Stein, Joshua S.

    2013-06-01

    It is important to be able to accurately simulate the variability of solar PV power plants for grid integration studies. We aim to inform integration studies of the ease of implementation and application-specific accuracy of current PV power plant output simulation methods. This report reviews methods for producing simulated high-resolution (sub-hour or even sub-minute) PV power plant output profiles for variability studies and describes their implementation. Two steps are involved in the simulations: estimation of average irradiance over the footprint of a PV plant and conversion of average irradiance to plant power output. Six models are described for simulating plant-average irradiance based on inputs of ground-measured irradiance, satellite-derived irradiance, or proxy plant measurements. The steps for converting plant-average irradiance to plant power output are detailed to understand the contributions to plant variability. A forthcoming report will quantify the accuracy of each method using application-specific validation metrics.

  5. MEASURING X-RAY VARIABILITY IN FAINT/SPARSELY SAMPLED ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Allevato, V.; Paolillo, M.; Papadakis, I.; Pinto, C.

    2013-07-01

    We study the statistical properties of the normalized excess variance of variability process characterized by a ''red-noise'' power spectral density (PSD), as in the case of active galactic nuclei (AGNs). We perform Monte Carlo simulations of light curves, assuming both a continuous and a sparse sampling pattern and various signal-to-noise ratios (S/Ns). We show that the normalized excess variance is a biased estimate of the variance even in the case of continuously sampled light curves. The bias depends on the PSD slope and on the sampling pattern, but not on the S/N. We provide a simple formula to account for the bias, which yields unbiased estimates with an accuracy better than 15%. We show that the normalized excess variance estimates based on single light curves (especially for sparse sampling and S/N < 3) are highly uncertain (even if corrected for bias) and we propose instead the use of an ''ensemble estimate'', based on multiple light curves of the same object, or on the use of light curves of many objects. These estimates have symmetric distributions, known errors, and can also be corrected for biases. We use our results to estimate the ability to measure the intrinsic source variability in current data, and show that they could also be useful in the planning of the observing strategy of future surveys such as those provided by X-ray missions studying distant and/or faint AGN populations and, more in general, in the estimation of the variability amplitude of sources that will result from future surveys such as Pan-STARRS and LSST.

  6. Selecting Observation Platforms for Optimized Anomaly Detectability under Unreliable Partial Observations

    SciTech Connect (OSTI)

    Wen-Chiao Lin; Humberto E. Garcia; Tae-Sic Yoo

    2011-06-01

    Diagnosers for keeping track on the occurrences of special events in the framework of unreliable partially observed discrete-event dynamical systems were developed in previous work. This paper considers observation platforms consisting of sensors that provide partial and unreliable observations and of diagnosers that analyze them. Diagnosers in observation platforms typically perform better as sensors providing the observations become more costly or increase in number. This paper proposes a methodology for finding an observation platform that achieves an optimal balance between cost and performance, while satisfying given observability requirements and constraints. Since this problem is generally computational hard in the framework considered, an observation platform optimization algorithm is utilized that uses two greedy heuristics, one myopic and another based on projected performances. These heuristics are sequentially executed in order to find best observation platforms. The developed algorithm is then applied to an observation platform optimization problem for a multi-unit-operation system. Results show that improved observation platforms can be found that may significantly reduce the observation platform cost but still yield acceptable performance for correctly inferring the occurrences of special events.

  7. Singular behavior of jet substructure observables

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Larkoski, Andrew J.; Moult, Ian

    2016-01-20

    Jet substructure observables play a central role at the Large Hadron Collider for identifying the boosted hadronic decay products of electroweak scale resonances. The complete description of these observables requires understanding both the limit in which hard substructure is resolved, as well as the limit of a jet with a single hard core. In this paper we study in detail the perturbative structure of two prominent jet substructure observables, N-subjettiness and the energy correlation functions, as measured on background QCD jets. In particular, we focus on the distinction between the limits in which two-prong structure is resolved or unresolved. Dependingmore » on the choice of subjet axes, we demonstrate that at fixed order, N-subjettiness can manifest myriad behaviors in the unresolved region: smooth tails, end-point singularities, or singularities in the physical region. The energy correlation functions, by contrast, only have non-singular perturbative tails extending to the end point. We discuss the effect of hadronization on the various observables with Monte Carlo simulation and demonstrate that the modeling of these effects with non-perturbative shape functions is highly dependent on the N-subjettiness axes definitions. Lastly, our study illustrates those regions of phase space that must be controlled for high-precision jet substructure calculations, and emphasizes how such calculations can be facilitated by designing substructure observables with simple singular structures.« less

  8. Review of Test Procedure for Determining HSPFs of Residential Variable-Speed Heat Pumps

    SciTech Connect (OSTI)

    Rice, C. Keith; Munk, Jeffrey D.; Shrestha, Som S.

    2015-08-01

    This report reviews the suitability of the existing Heating Seasonal Performance Factor (HSPF) ratings and testing requirements for the current generation of variable-speed (VS) air-source heat pumps. Recent field test results indicate larger discrepancies between rated HSPF and field-observed HSPF for VS models than for single-speed models in the same houses. These findings suggest that the heating season test and ratings procedure should be revisited for VS heat pumps. The ratings and testing procedures are described in ANSI/AHRI 210/240 (2008) for single-speed, two-capacity, and variable-speed units. Analysis of manufacturer and independent test performance data on VS units reveals why the current VS testing/ratings procedure results in overly optimistic HSPF ratings for some VS units relative to other types of heat pumps. This is due to a combination of extrapolation of low speed test data beyond the originally anticipated ambient temperature operating range and the constraints of unit controls, which prevent low speed operation over the range of ambient temperatures assumed in the procedure for low speed. As a result, the HSPFs of such units are being overpredicted relative to those for single- and two-capacity designs. This overprediction has been found to be significantly reduced by use in the HSPF ratings procedure of an alternative higher-load heating load line, described in a companion report (Rice et al., 2015).

  9. The Mechanisms of Natural Variability and its Interaction with Anthropogenic Climate Change Final Report

    SciTech Connect (OSTI)

    Vallis, Geoffrey K.

    2015-02-01

    The project had two main components. The first concerns estimating the climate sensitivity in the presence of forcing uncertainty and natural variability. Climate sensitivity is the increase in the average surface temperature for a given increase in greenhouse gases, for example a doubling of carbon dioxide. We have provided new, probabilistic estimates of climate sensitivity using a simple climate model an the observed warming in the 20th century, in conjunction with ideas in data assimilation and parameter estimation developed in the engineering community. The estimates combine the uncertainty in the anthropogenic aerosols with the uncertainty arising because of natural variability. The second component concerns how the atmospheric circulation itself might change with anthropogenic global warming. We have shown that GCMs robustly predict an increase in the length scale of eddies, and we have also explored the dynamical mechanisms whereby there might be a shift in the latitude of the jet stream associated with anthropogenic warming. Such shifts in the jet might cause large changes in regional climate, potentially larger than the globally-averaged signal itself. We have also shown that the tropopause robustly increases in height with global warming, and that the Hadley Cell expands, and that the expansion of the Hadley Cell is correlated with the polewards movement of the mid-latitude jet.

  10. Potential Reductions in Variability with Alternative Approaches to Balancing Area Cooperation with High Penetrations of Variable Generation

    SciTech Connect (OSTI)

    Milligan, M.; Kirby, B.; Beuning, S.

    2010-08-01

    The work described in this report was performed by the National Renewable Energy Laboratory (NREL) and funded by the Office of the Energy Efficiency and Renewable Energy, U.S. Department of Energy (EERE DOE). This project is a joint project with the Pacific Northwest National Laboratory. This report evaluates the physical characteristics that improve the ability of the power system to absorb variable generation. It then uses evidence from electricity markets in the Eastern Interconnection of the United States to show how large, fast energy markets can help with integration. The concept of Virtual Balancing Area is introduced, a concept that covers a broad range of cooperative measures that can be undertaken by balancing areas to help manage variability.

  11. Demonstration of a Variable Phase Turbine Power System for Low Temperature

    Office of Environmental Management (EM)

    Geothermal Resources | Department of Energy Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources Project objectives: Demonstrate a 1 megawatt Variable Phase Turbine and Variable Phase Cycle with low temperature brine. PDF icon low_hays_variable_phase_turbine.pdf More Documents & Publications track 1: Low Temp | geothermal 2015 peer review track 3:

  12. Testing the copernican principle via cosmological observations

    SciTech Connect (OSTI)

    Bolejko, Krzysztof; Wyithe, J. Stuart B. E-mail: swyithe@unimelb.edu.au

    2009-02-15

    Observations of distances to Type-Ia supernovae can be explained by cosmological models that include either a gigaparsec-scale void, or a cosmic flow, without the need for Dark Energy. Instead of invoking dark energy, these inhomogeneous models instead violate the Copernican Principle. we show that current cosmological observations (Supernovae, Baryon Acoustic Oscillations and estimates of the Hubble parameters based on the age of the oldest stars) are not able to rule out inhomogeneous anti-Copernican models. The next generation of surveys for baryonic acoustic oscillations will be sufficiently precise to either validate the Copernican Principle or determine the existence of a local Gpc scale inhomogeneity.

  13. ARM - PI Product - Niamey Dust Observations

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

    Dust Observations ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Niamey Dust Observations Niamey aerosol are composed of two main components: dust due to the proximity of the Sahara Desert, and soot from local and regional biomass burning. The purpose of this data product is to identify when the local conditions are dominated by the dust component so that the properties of the dust events can be

  14. APOSTLE: 11 TRANSIT OBSERVATIONS OF TrES-3b

    SciTech Connect (OSTI)

    Kundurthy, P.; Becker, A. C.; Agol, E.; Barnes, R.; Williams, B.

    2013-02-10

    The Apache Point Survey of Transit Lightcurves of Exoplanets (APOSTLE) observed 11 transits of TrES-3b over two years in order to constrain system parameters and look for transit timing and depth variations. We describe an updated analysis protocol for APOSTLE data, including the reduction pipeline, transit model, and Markov Chain Monte Carlo analyzer. Our estimates of the system parameters for TrES-3b are consistent with previous estimates to within the 2{sigma} confidence level. We improved the errors (by 10%-30%) on system parameters such as the orbital inclination (i {sub orb}), impact parameter (b), and stellar density ({rho}{sub *}) compared to previous measurements. The near-grazing nature of the system, and incomplete sampling of some transits, limited our ability to place reliable uncertainties on individual transit depths and hence we do not report strong evidence for variability. Our analysis of the transit timing data shows no evidence for transit timing variations and our timing measurements are able to rule out super-Earth and gas giant companions in low-order mean motion resonance with TrES-3b.

  15. Observational constraints on Tachyon and DBI inflation

    SciTech Connect (OSTI)

    Li, Sheng; Liddle, Andrew R. E-mail: arl@roe.ac.uk

    2014-03-01

    We present a systematic method for evaluation of perturbation observables in non-canonical single-field inflation models within the slow-roll approximation, which allied with field redefinitions enables predictions to be established for a wide range of models. We use this to investigate various non-canonical inflation models, including Tachyon inflation and DBI inflation. The Lambert W function will be used extensively in our method for the evaluation of observables. In the Tachyon case, in the slow-roll approximation the model can be approximated by a canonical field with a redefined potential, which yields predictions in better agreement with observations than the canonical equivalents. For DBI inflation models we consider contributions from both the scalar potential and the warp geometry. In the case of a quartic potential, we find a formula for the observables under both non-relativistic (sound speed c{sub s}{sup 2}?1) and relativistic behaviour (c{sub s}{sup 2}||1) of the scalar DBI inflaton. For a quadratic potential we find two branches in the non-relativistic c{sub s}{sup 2}?1 case, determined by the competition of model parameters, while for the relativistic case c{sub s}{sup 2}?0, we find consistency with results already in the literature. We present a comparison to the latest Planck satellite observations. Most of the non-canonical models we investigate, including the Tachyon, are better fits to data than canonical models with the same potential, but we find that DBI models in the slow-roll regime have difficulty in matching the data.

  16. HIGH LEVEL WASTE SLUDGE BATCH 4 VARIABILITY STUDY

    SciTech Connect (OSTI)

    Fox, K; Tommy Edwards, T; David Peeler, D; David Best, D; Irene Reamer, I; Phyllis Workman, P

    2006-10-02

    The Defense Waste Processing Facility (DWPF) is preparing for vitrification of High Level Waste (HLW) Sludge Batch 4 (SB4) in early FY2007. To support this process, the Savannah River National Laboratory (SRNL) has provided a recommendation to utilize Frit 503 for vitrifying this sludge batch, based on the composition projection provided by the Liquid Waste Organization on June 22, 2006. Frit 418 was also recommended for possible use during the transition from SB3 to SB4. A critical step in the SB4 qualification process is to demonstrate the applicability of the durability models, which are used as part of the DWPF's process control strategy, to the glass system of interest via a variability study. A variability study is an experimentally-driven assessment of the predictability and acceptability of the quality of the vitrified waste product that is anticipated from the processing of a sludge batch. At the DWPF, the durability of the vitrified waste product is not directly measured. Instead, the durability is predicted using a set of models that relate the Product Consistency Test (PCT) response of a glass to the chemical composition of that glass. In addition, a glass sample is taken during the processing of that sludge batch, the sample is transmitted to SRNL, and the durability is measured to confirm acceptance. The objective of a variability study is to demonstrate that these models are applicable to the glass composition region anticipated during the processing of the sludge batch - in this case the Frit 503 - SB4 compositional region. The success of this demonstration allows the DWPF to confidently rely on the predictions of the durability/composition models as they are used in the control of the DWPF process.

  17. Residential Variable-Capacity Heat Pumps Sized to Heating Loads

    SciTech Connect (OSTI)

    Munk, Jeffrey D.; Jackson, Roderick K.; Odukomaiya, Adewale; Gehl, Anthony C.

    2014-01-01

    Variable capacity heat pumps are an emerging technology offering significant energy savings potential and improved efficiency. With conventional single-speed systems, it is important to appropriately size heat pumps for the cooling load as over-sizing would result in cycling and insufficient latent capacity required for humidity control. These appropriately sized systems are often under-sized for the heating load and require inefficient supplemental electric resistance heat to meet the heating demand. Variable capacity heat pumps address these shortcomings by providing an opportunity to intentionally size systems for the dominant heating season load without adverse effects of cycling or insufficient dehumidification in the cooling season. This intentionally-sized system could result in significant energy savings in the heating season, as the need for inefficient supplemental electric resistance heat is drastically reduced. This is a continuation of a study evaluating the energy consumption of variable capacity heat pumps installed in two unoccupied research homes in Farragut, a suburb of Knoxville, Tennessee. In this particular study, space conditioning systems are intentionally sized for the heating season loads to provide an opportunity to understand and evaluate the impact this would have on electric resistance heat use and dehumidification. The results and conclusions drawn through this research are valid and specific for portions of the Southeastern and Midwestern United States falling in the mixed-humid climate zone. While other regions in the U.S. do not experience this type of climate, this work provides a basis for, and can help understand the implications of other climate zones on residential space conditioning energy consumption. The data presented here will provide a framework for fine tuning residential building EnergyPlus models that are being developed.

  18. Extension of latin hypercube samples with correlated variables.

    SciTech Connect (OSTI)

    Hora, Stephen Curtis; Helton, Jon Craig; Sallaberry, Cedric J. PhD.

    2006-11-01

    A procedure for extending the size of a Latin hypercube sample (LHS) with rank correlated variables is described and illustrated. The extension procedure starts with an LHS of size m and associated rank correlation matrix C and constructs a new LHS of size 2m that contains the elements of the original LHS and has a rank correlation matrix that is close to the original rank correlation matrix C. The procedure is intended for use in conjunction with uncertainty and sensitivity analysis of computationally demanding models in which it is important to make efficient use of a necessarily limited number of model evaluations.

  19. Variable temperature electrochemical strain microscopy of Sm-doped ceria

    SciTech Connect (OSTI)

    Jesse, Stephen; Morozovska, A. N.; Kalinin, Sergei V; Eliseev, E. A.; Yang, Nan; Doria, Sandra; Tebano, Antonello

    2013-01-01

    Variable temperature electrochemical strain microscopy has been used to study the electrochemical activity of Sm-doped ceria as a function of temperature and bias. The electrochemical strain microscopy hysteresis loops have been collected across the surface at different temperatures and the relative activity at different temperatures has been compared. The relaxation behavior of the signal at different temperatures has been also evaluated to relate kinetic process during bias induced electrochemical reactions with temperature and two different kinetic regimes have been identified. The strongly non-monotonic dependence of relaxation behavior on temperature is interpreted as evidence for water-mediated mechanisms.

  20. Polymer performance in cooling water: The influence of process variables

    SciTech Connect (OSTI)

    Amjad, Z.; Pugh, J.; Zibrida, J.; Zuhl, B.

    1997-01-01

    The key to the efficacy of phosphate and phosphonates in stabilized phosphate and all-organic cooling water treatment (CWT) programs is the presence and performance of polymeric inhibitors/dispersants. The performance of polymeric additives used in CWT programs can be adversely impacted by the presence of iron, phosphonate, or cationic polymer and influenced by a variety of process variables including system pH and temperature. In this article, the performance of several polymeric additives is evaluated under a variety of stressed conditions.

  1. Quantifying Interannual Variability for Photovoltaic Systems in PVWatts

    SciTech Connect (OSTI)

    Ryberg, David Severin; Freeman, Janine; Blair, Nate

    2015-10-01

    The National Renewable Energy Laboratory's (NREL's) PVWatts is a relatively simple tool used by industry and individuals alike to easily estimate the amount of energy a photovoltaic (PV) system will produce throughout the course of a typical year. PVWatts Version 5 has previously been shown to be able to reasonably represent an operating system's output when provided with concurrent weather data, however this type of data is not available when estimating system output during future time frames. For this purpose PVWatts uses weather data from typical meteorological year (TMY) datasets which are available on the NREL website. The TMY files represent a statistically 'typical' year which by definition excludes anomalous weather patterns and as a result may not provide sufficient quantification of project risk to the financial community. It was therefore desired to quantify the interannual variability associated with TMY files in order to improve the understanding of risk associated with these projects. To begin to understand the interannual variability of a PV project, we simulated two archetypal PV system designs, which are common in the PV industry, in PVWatts using the NSRDB's 1961-1990 historical dataset. This dataset contains measured hourly weather data and spans the thirty years from 1961-1990 for 239 locations in the United States. To note, this historical dataset was used to compose the TMY2 dataset. Using the results of these simulations we computed several statistical metrics which may be of interest to the financial community and normalized the results with respect to the TMY energy prediction at each location, so that these results could be easily translated to similar systems. This report briefly describes the simulation process used and the statistical methodology employed for this project, but otherwise focuses mainly on a sample of our results. A short discussion of these results is also provided. It is our hope that this quantification of the interannual variability of PV systems will provide a starting point for variability considerations in future PV system designs and investigations. however this type of data is not available when estimating system output during future time frames.

  2. Variable flow control for a nuclear reactor control rod

    DOE Patents [OSTI]

    Carleton, Richard D.; Bhattacharyya, Ajay

    1978-01-01

    A variable flow control for a control rod assembly of a nuclear reactor that depends on turbulent friction though an annulus. The annulus is formed by a piston attached to the control rod drive shaft and a housing or sleeve fitted to the enclosure housing the control rod. As the nuclear fuel is burned up and the need exists for increased reactivity, the control rods are withdrawn, which increases the length of the annulus and decreases the rate of coolant flow through the control rod assembly.

  3. IDENTIFICATION OF NEW GAMMA-RAY BLAZAR CANDIDATES WITH MULTIFREQUENCY ARCHIVAL OBSERVATIONS

    SciTech Connect (OSTI)

    Cowperthwaite, Philip S.; Massaro, F.; D'Abrusco, R.; Paggi, A.; Smith, Howard A.; Tosti, G.

    2013-11-01

    Blazars are a highly variable, radio-loud subclass of active galactic nuclei. In order to better understand such objects we must be able to easily identify candidate blazars from the growing population of unidentified sources. Working toward this goal, we attempt to identify new gamma-ray blazar candidates from a sample of 102 previously unidentified sources. These sources are selected from The Astronomer's Telegram and the literature on the basis of non-periodic variability and multi-wavelength behavior. We then attempt to associate these objects to an IR counterpart in the Wide-field Infrared Survey Explorer all-sky survey. We are able to identify 16 candidate sources whose IR colors are consistent with those of the blazar population. Of those, 13 sources have IR colors indicative of being gamma-ray emitting blazar candidates. These sources all possess archival multi-wavelength observations that support their blazar-like nature.

  4. First direct observation of muon antineutrino disappearance

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamson, P.

    2011-07-05

    This letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν̄μ production, accumulating an exposure of 1.71 x 1020 protons on target. In the Far Detector, 97 charged current ν̄μ events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm̄2| = (3.36-0.40 +0.46(stat.) ± 0.06(syst.)) x 10-3 eV2, sin2(2 θ̄) = 0.86-0.12+0.11 (stat.) ± 0.01(syst.). The MINOS νμ and ν̄μ measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

  5. Observational Approach to Chromium Site Remediation - 13266

    SciTech Connect (OSTI)

    Scott Myers, R.

    2013-07-01

    Production reactors at the U.S. Department of Energy's (DOE) Hanford Site in Richland, Washington, required massive quantities of water for reactor cooling and material processing. To reduce corrosion and the build-up of scale in pipelines and cooling systems, sodium dichromate was added to the water feedstock. Spills and other releases at the makeup facilities, as well as leaks from miles of pipelines, have led to numerous areas with chromium-contaminated soil and groundwater, threatening fish populations in the nearby Columbia River. Pump-and-treat systems have been installed to remove chromium from the groundwater, but significant contamination remain in the soil column and poses a continuing threat to groundwater and the Columbia River. Washington Closure Hanford, DOE, and regulators are working on a team approach that implements the observational approach, a strategy for effectively dealing with the uncertainties inherent in subsurface conditions. Remediation of large, complex waste sites at a federal facility is a daunting effort. It is particularly difficult to perform the work in an environment of rapid response to changing field and contamination conditions. The observational approach, developed by geotechnical engineers to accommodate the inherent uncertainties in subsurface conditions, is a powerful and appropriate method for site remediation. It offers a structured means of quickly moving into full remediation and responding to the variations and changing conditions inherent in waste site cleanups. A number of significant factors, however, complicate the application of the observational approach for chromium site remediation. Conceptual models of contamination and site conditions are difficult to establish and get consensus on. Mid-stream revisions to the design of large excavations are time-consuming and costly. And regulatory constraints and contract performance incentives can be impediments to the flexible responses required under the observational approach. The WCH project team is working closely with stakeholders and taking a number of steps to meet these challenges in a continuing effort to remediate chromium contaminated soil in an efficient and cost-effective manner. (authors)

  6. LNG Observer: Second Qatargas train goes onstream

    SciTech Connect (OSTI)

    1997-01-01

    The January-February, 1997 issue of the LNG Observer is presented. The following topics are discussed: second Qatargas train goes onstream; financing for the eighth Indonesian liquefaction train; Koreans take stakes in Oman LNG; US imports and exports of LNG in 1996; A 60% increase in proved reserves on the North West Shelf; proposals for Indian LNG terminal CEDIGAZ forecasts world LNG trade by 2010; growth for North African gas production and exports; and new forecast sees strong growth for Asian gas.

  7. Self-potential observations during hydraulic fracturing

    SciTech Connect (OSTI)

    Moore, Jeffrey R.; Glaser, Steven D.

    2007-09-13

    The self-potential (SP) response during hydraulic fracturing of intact Sierra granite was investigated in the laboratory. Excellent correlation of pressure drop and SP suggests that the SP response is created primarily by electrokinetic coupling. For low pressures, the variation of SP with pressure drop is linear, indicating a constant coupling coefficient (Cc) of -200 mV/MPa. However for pressure drops >2 MPa, the magnitude of the Cc increases by 80% in an exponential trend. This increasing Cc is related to increasing permeability at high pore pressures caused by dilatancy of micro-cracks, and is explained by a decrease in the hydraulic tortuosity. Resistivity measurements reveal a decrease of 2% prior to hydraulic fracturing and a decrease of {approx}35% after fracturing. An asymmetric spatial SP response created by injectate diffusion into dilatant zones is observed prior to hydraulic fracturing, and in most cases this SP variation revealed the impending crack geometry seconds before failure. At rupture, injectate rushes into the new fracture area where the zeta potential is different than in the rock porosity, and an anomalous SP spike is observed. After fracturing, the spatial SP distribution reveals the direction of fracture propagation. Finally, during tensile cracking in a point load device with no water flow, a SP spike is observed that is caused by contact electrification. However, the time constant of this event is much less than that for transients observed during hydraulic fracturing, suggesting that SP created solely from material fracture does not contribute to the SP response during hydraulic fracturing.

  8. First Direct Observation of Spinons and Holons

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

    First Direct Observation of Spinons and Holons Print Spin and charge are inseparable traits of an electron, but in one-dimensional solids, a 40-year-old theory predicts their separation into "collective" modes-as independent excitation quanta called spinons and holons. Angle-resolved photoemission spectroscopy (ARPES) should provide the most direct evidence of this spin-charge separation, as the single quasiparticle peak splits into a spinon-holon two-peak structure. However, despite

  9. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were proposed theoretically in the late 1960s, and indirect evidence of them has

  10. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were proposed theoretically in the late 1960s, and indirect evidence of them has

  11. First Direct Observation of Spinons and Holons

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

    First Direct Observation of Spinons and Holons Print Spin and charge are inseparable traits of an electron, but in one-dimensional solids, a 40-year-old theory predicts their separation into "collective" modes-as independent excitation quanta called spinons and holons. Angle-resolved photoemission spectroscopy (ARPES) should provide the most direct evidence of this spin-charge separation, as the single quasiparticle peak splits into a spinon-holon two-peak structure. However, despite

  12. First Direct Observation of Spinons and Holons

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

    First Direct Observation of Spinons and Holons Print Spin and charge are inseparable traits of an electron, but in one-dimensional solids, a 40-year-old theory predicts their separation into "collective" modes-as independent excitation quanta called spinons and holons. Angle-resolved photoemission spectroscopy (ARPES) should provide the most direct evidence of this spin-charge separation, as the single quasiparticle peak splits into a spinon-holon two-peak structure. However, despite

  13. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were proposed theoretically in the late 1960s, and indirect evidence of them has

  14. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were proposed theoretically in the late 1960s, and indirect evidence of them has

  15. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were proposed theoretically in the late 1960s, and indirect evidence of them has

  16. First Observation of Plasmarons in Graphene

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

    First Observation of Plasmarons in Graphene Print An international team of scientists performing angle-resolved photoemission spectroscopy (ARPES) experiments at ALS Beamline 7.0.1 have found that composite particles called plasmarons play a vital role in determining graphene's properties. A plasmaron consists of a charge carrier (electron or hole) coupled with a plasmon-an electron density wave. Although plasmarons were proposed theoretically in the late 1960s, and indirect evidence of them has

  17. Program Management Review Steering Committee Observations

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

    Program Management Review Jim Dooley Forest Concepts, LLC Steering Committee Observations 2 Members Steering Committee: Member Affiliation Jim Dooley Forest Concepts, LLC Dean Dreamel ExxonMobil/University of California, Berkeley Jim Kellis DuPont Mike Lakeman Boeing and Algae Biomass Organization Valri Lightner DOE Loan Programs Office Jack McDonald Independent Shelie Miller University of Michigan Carol Werner Environmental and Energy Study Institute 3 Outline I. BETO Portfolio II. Coordination

  18. ARM - Arctic Lower Troposphere Observed Structure (ALTOS)

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

    govField CampaignsArctic Lower Troposphere Observed Structure (ALTOS) Related Links ALTOS Home ISDAC Home ARM Field Campaigns Home News Department of Energy Announces $7 Million in Funding for Climate Research Field Studies October 23, 2008 Tethered Balloon Headlines Field Campaign at North Slope of Alaska October 28, 2010 Arctic Campaign Cut Short; Spring Restart A Possibility November 3, 2010 ALTOS Backgrounder (PDF, 1.3MB) Experiment Planning Proposal Abstract Science Plan (PDF, 902KB)

  19. Bright microwave pulses from PSR B0531+21 observed with a prototype transient survey receiver

    SciTech Connect (OSTI)

    O'Dea, J. Andrew; Cheng, Tsan-Huei; Buu, Chau M.; Asmar, Sami W.; Armstrong, J. W.; Jenet, F. A.; Beroiz, Martin

    2014-05-01

    Recent discoveries of transient radio events have renewed interest in time-variable astrophysical phenomena. Many radio transient events are rare, requiring long observing times for reliable statistical study. The National Aeronautics and Space Administration/Jet Propulsion Laboratory's Deep Space Network (DSN) tracks spacecraft nearly continuously with 13 large-aperture, low system temperature radio antennas. During normal spacecraft operations, the DSN processes only a small fraction of the pre-detection bandwidth available from these antennas; any information in the remaining bandwidth, e.g., from an astronomical source in the same antenna beam as the spacecraft, is currently ignored. As a firmware modification to the standard DSN tracking receiver, we built a prototype receiver that could be used for astronomical transient surveys. Here, we demonstrate the receiver's utility through observations of bright pulses from the Crab pulsar and describe attributes of potential transient survey observations piggybacking on operational DSN tracks.

  20. Observing System Simulation Experiments (OSSEs) for the Mid-Columbia Basin

    SciTech Connect (OSTI)

    Zack, J; Natenberg, E J; Knowe, G V; Waight, K; Manobianco, J; Hanley, D; Kamath, C

    2011-09-13

    The overall goal of this multi-phased research project known as WindSENSE is to develop an observation system deployment strategy that would improve wind power generation forecasts. The objective of the deployment strategy is to produce the maximum benefit for 1- to 6-hour ahead forecasts of wind speed at hub-height ({approx}80 m). In this phase of the project the focus is on the Mid-Columbia Basin region, which encompasses the Bonneville Power Administration (BPA) wind generation area (Figure 1) that includes the Klondike, Stateline, and Hopkins Ridge wind plants. There are two tasks in the current project effort designed to validate the Ensemble Sensitivity Analysis (ESA) observational system deployment approach in order to move closer to the overall goal: (1) Perform an Observing System Experiment (OSE) using a data denial approach. The results of this task are presented in a separate report. (2) Conduct a set of Observing System Simulation Experiments (OSSE) for the Mid-Colombia basin region. This report presents the results of the OSSE task. The specific objective is to test strategies for future deployment of observing systems in order to suggest the best and most efficient ways to improve wind forecasting at BPA wind farm locations. OSSEs have been used for many years in meteorology to evaluate the potential impact of proposed observing systems, determine tradeoffs in instrument design, and study the most effective data assimilation methodologies to incorporate the new observations into numerical weather prediction (NWP) models (Atlas 1997; Lord 1997). For this project, a series of OSSEs will allow consideration of the impact of new observing systems of various types and in various locations.

  1. Uncovering the intrinsic variability of gamma-ray bursts

    SciTech Connect (OSTI)

    Golkhou, Vahid Z.; Butler, Nathaniel R., E-mail: vgolkhou@asu.edu, E-mail: natbutler@asu.edu [Cosmology Initiative, Arizona State University, Tempe, AZ 85287, USA. (United States)

    2014-05-20

    We develop a robust technique to determine the minimum variability timescale for gamma-ray burst (GRB) light curves, utilizing Haar wavelets. Our approach averages over the data for a given GRB, providing an aggregate measure of signal variation while also retaining sensitivity to narrow pulses within complicated time series. In contrast to previous studies using wavelets, which simply define the minimum timescale in reference to the measurement noise floor, our approach identifies the signature of temporally smooth features in the wavelet scaleogram and then additionally identifies a break in the scaleogram on longer timescales as a signature of a true, temporally unsmooth light curve feature or features. We apply our technique to the large sample of Swift GRB gamma-ray light curves and for the first timedue to the presence of a large number of GRBs with measured redshiftdetermine the distribution of minimum variability timescales in the source frame. We find a median minimum timescale for long-duration GRBs in the source frame of ?t {sub min} = 0.5 s, with the shortest timescale found being on the order of 10 ms. This short timescale suggests a compact central engine (3 10{sup 3} km). We discuss further implications for the GRB fireball model and present a tantalizing correlation between the minimum timescale and redshift, which may in part be due to cosmological time dilation.

  2. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, E.

    1998-08-25

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility. 14 figs.

  3. Variable Speed Wind Turbine Generator with Zero-sequence Filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-08-25

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  4. Variable speed wind turbine generator with zero-sequence filter

    DOE Patents [OSTI]

    Muljadi, Eduard (Golden, CO)

    1998-01-01

    A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

  5. Survey of Variable Generation Forecasting in the West: August 2011 - June 2012

    SciTech Connect (OSTI)

    Porter, K.; Rogers, J.

    2012-04-01

    This report surveyed Western Interconnection Balancing Authorities regarding their implementation of variable generation forecasting, the lessons learned to date, and recommendations they would offer to other Balancing Authorities who are considering variable generation forecasting. Our survey found that variable generation forecasting is at an early implementation stage in the West. Eight of the eleven Balancing Authorities interviewed began forecasting in 2008 or later. It also appears that less than one-half of the Balancing Authorities in the West are currently utilizing variable generation forecasting, suggesting that more Balancing Authorities in the West will engage in variable generation forecasting should more variable generation capacity be added.

  6. HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR SEARCH USING

    Office of Scientific and Technical Information (OSTI)

    OPTICAL VARIABILITY (Journal Article) | SciTech Connect HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR SEARCH USING OPTICAL VARIABILITY Citation Details In-Document Search Title: HIGHLY VARIABLE OBJECTS IN THE PALOMAR-QUEST SURVEY: A BLAZAR SEARCH USING OPTICAL VARIABILITY We identify 3113 highly variable objects in 7200 deg{sup 2} of the Palomar-QUEST (PQ) Survey, which each varied by more than 0.4 mag simultaneously in two broadband optical filters on timescales from hours

  7. Emergence of granular-sized magnetic bubbles through the solar atmosphere. I. Spectropolarimetric observations and simulations

    SciTech Connect (OSTI)

    Ortiz, Ada; Hansteen, Viggo H.; Van der Voort, Luc Rouppe [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway); Bellot Rubio, Luis R. [Instituto de Astrofsica de Andaluca (CSIC), Apdo. 3040, E-18080 Granada (Spain); De la Cruz Rodrguez, Jaime, E-mail: ada@astro.uio.no [Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala (Sweden)

    2014-02-01

    We study a granular-sized magnetic flux emergence event that occurred in NOAA 11024 in 2009 July. The observations were made with the CRISP spectropolarimeter at the Swedish 1 m Solar Telescope achieving a spatial resolution of 0.''14. Simultaneous full Stokes observations of the two photospheric Fe I lines at 630.2 nm and the chromospheric Ca II 854.2 nm line allow us to describe in detail the emergence process across the solar atmosphere. We report here on three-dimensional (3D) semi-spherical bubble events, where instead of simple magnetic footpoints, we observe complex semi-circular feet straddling a few granules. Several phenomena occur simultaneously, namely, abnormal granulation, separation of opposite-polarity legs, and brightenings at chromospheric heights. However, the most characteristic signature in these events is the observation of a dark bubble in filtergrams taken in the wings of the Ca II 854.2 nm line. There is a clear coincidence between the emergence of horizontal magnetic field patches and the formation of the dark bubble. We can infer how the bubble rises through the solar atmosphere as we see it progressing from the wings to the core of Ca II 854.2 nm. In the photosphere, the magnetic bubble shows mean upward Doppler velocities of 2 km s{sup 1} and expands at a horizontal speed of 4 km s{sup 1}. In about 3.5 minutes it travels some 1100 km to reach the mid chromosphere, implying an average ascent speed of 5.2 km s{sup 1}. The maximum separation attained by the magnetic legs is 6.''6. From an inversion of the observed Stokes spectra with the SIR code, we find maximum photospheric field strengths of 480 G and inclinations of nearly 90 in the magnetic bubble interior, along with temperature deficits of up to 250 K at log ? = 2 and above. To aid the interpretation of the observations, we carry out 3D numerical simulations of the evolution of a horizontal, untwisted magnetic flux sheet injected in the convection zone, using the Bifrost code. The computational domain spans from the upper convection zone to the lower corona. In the modeled chromosphere, the rising flux sheet produces a large, cool, magnetized bubble. We compare this bubble with the observed ones and find excellent agreement, including similar field strengths and velocity signals in the photosphere and chromosphere, temperature deficits, ascent speeds, expansion velocities, and lifetimes.

  8. Relative Contributions of Mean-State Shifts and ENSO-Driven Variability to Precipitation Changes in a Warming Climate

    SciTech Connect (OSTI)

    Bonfils, Celine; Santer, Benjamin D.; Phillips, Thomas J.; Marvel, Kate; Leung, Lai-Yung R.; Doutriaux, Charles; Capotondi, Antonietta

    2015-12-15

    The El Nio-Southern Oscillation (ENSO) is an important driver of regional hydroclimate variability through far-reaching teleconnections. Most climate models project an increase in the frequency of extreme El Nio events under increased greenhouse-gas (GHG) forcing. However, it is unclear how other aspects of ENSO and ENSO-driven teleconnections will evolve in the future. Here, we identify in 20th century sea-surface temperature (SST) observations a time-invariant ENSO-like (ENSOL) pattern that is largely uncontaminated by GHG forcing. We use this pattern to investigate the future precipitation (P) response to ENSO-like SST anomalies. Models that better capture observed ENSOL characteristics produce P teleconnection patterns that are in better accord with observations and more stationary in the 21st century. We decompose the future P response to ENSOL into the sum of three terms: (1) the change in P mean state, (2) the historical P response to ENSOL, and (3) a future enhancement in the P response to ENSOL. In many regions, this last term can aggravate the P extremes associated with ENSO variability. This simple decomposition allows us to identify regions likely to experience ENSOL-induced P changes that are without precedent in the current climate.

  9. Direct Observation of Paramagnons in Palladium

    SciTech Connect (OSTI)

    Doubble, R.; Hayden, S M.; Dai, Pengcheng; Mook Jr, Herbert A; Thompson, James R; Frost, C.

    2010-01-01

    We report an inelastic neutron scattering study of the spin fluctuations in the nearly ferromagnetic element palladium. Dispersive over-damped collective magnetic excitations or 'paramagnons' are observed up to 128 meV. We analyze our results in terms of a Moriya-Lonzarich-type spin-fluctuation model and estimate the contribution of the spin fluctuations to the low-temperature heat capacity. In spite of the paramagnon excitations being relatively strong, their relaxation rates are large. This leads to a small contribution to the low-temperature electronic specific heat.

  10. William Herschel, the First Observational Cosmologist

    ScienceCinema (OSTI)

    Lemonick, Michael [Princeton University and Time Magazine, Princeton, New Jersey, United States

    2010-01-08

    In the late 1700s, a composer, orchestra director and soloist named William Herschel became fascinated with astronomy, and, having built his own reflecting telescope, went out in his garden in Bath, England, one night and discovered Uranus?the first planet in human history ever found by an individual. The feat earned him a lifetime pension from King George III. But Herschel considered the discovery to be relatively unimportant in comparison to his real work: understanding the composition, structure and evolution of the universe. In pursuing that work, he became the first observational cosmologist.

  11. SU-E-T-174: Evaluation of the Optimal Intensity Modulated Radiation Therapy Plans Done On the Maximum and Average Intensity Projection CTs

    SciTech Connect (OSTI)

    Jurkovic, I; Stathakis, S; Li, Y; Patel, A; Vincent, J; Papanikolaou, N; Mavroidis, P

    2014-06-01

    Purpose: To determine the difference in coverage between plans done on average intensity projection and maximum intensity projection CT data sets for lung patients and to establish correlations between different factors influencing the coverage. Methods: For six lung cancer patients, 10 phases of equal duration through the respiratory cycle, the maximum and average intensity projections (MIP and AIP) from their 4DCT datasets were obtained. MIP and AIP datasets had three GTVs delineated (GTVaip delineated on AIP, GTVmip delineated on MIP and GTVfus delineated on each of the 10 phases and summed up). From the each GTV, planning target volumes (PTV) were then created by adding additional margins. For each of the PTVs an IMRT plan was developed on the AIP dataset. The plans were then copied to the MIP data set and were recalculated. Results: The effective depths in AIP cases were significantly smaller than in MIP (p < 0.001). The Pearson correlation coefficient of r = 0.839 indicates strong degree of positive linear relationship between the average percentage difference in effective depths and average PTV coverage on the MIP data set. The V2 0 Gy of involved lung depends on the PTV coverage. The relationship between PTVaip mean CT number difference and PTVaip coverage on MIP data set gives r = 0.830. When the plans are produced on MIP and copied to AIP, r equals ?0.756. Conclusion: The correlation between the AIP and MIP data sets indicates that the selection of the data set for developing the treatment plan affects the final outcome (cases with high average percentage difference in effective depths between AIP and MIP should be calculated on AIP). The percentage of the lung volume receiving higher dose depends on how well PTV is covered, regardless of on which set plan is done.

  12. Reported Significant Observation (RSO) studies. Revision 1

    SciTech Connect (OSTI)

    Eicher, R.W.

    1992-12-01

    The Reported Significant Observation (RSO) study used in the field of safety is an information-gathering technique where employee-participants describe situations they have personally witnessed involving good and bad practices and safe and unsafe conditions. This information is useful in the risk assessment process because it focuses on hazards and thereby facilitates their elimination. However, RSO cannot be the only component in a risk assessment program. Used by the Air Force in their aviation psychology program and further developed by John C. Flanagan, RSO is more commonly known as the ``Critical Incident Technique.`` However, the words ``Critical`` and ``Incident`` had other connotations in nuclear safety, prompting early users within the Aerojet Nuclear Company to coin the more fitting title of ``Reported Significant Observations.`` The technique spread slowly in the safety field primarily because the majority of users were researchers interested in after-the-fact data, with application to everyday problems and behavioral factors. RSO was formally recognized as a significant hazard reduction tool during the development of the Management Oversight and Risk Tree (MORT) program for the US Atomic Energy Commission. The Department of Energy (DOE) has, in turn, adopted MORT for its system safety program, and this has resulted in RSO being a modern and viable technique for DOE contractor safety programs.

  13. Boundary Layer Cloudiness Parameterizations Using ARM Observations

    SciTech Connect (OSTI)

    Bruce Albrecht

    2004-09-15

    This study used DOE ARM data and facilities to: (1) study macroscopic properties of continental stratus clouds at SGP and the factors controlling these properties, (2) develop a scientific basis for understanding the processes responsible for the formation of boundary layer clouds using ARM observations in conjunction with simple parametric models and LES, and (3) evaluate cumulus cloud characteristics retrieved from the MMCR operating at TWP-Nauru. In addition we have used high resolution 94 GHz observations of boundary layer clouds and precipitation to: (1) develop techniques for using high temporal resolution Doppler velocities to study large-eddy circulations and turbulence in boundary layer clouds and estimate the limitations of using current and past MMCR data for boundary layer cloud studies, (2) evaluate the capability and limitations of the current MMCR data for estimating reflectivity, vertical velocities, and spectral under low- signal-to-noise conditions associated with weak no n-precipitating clouds, (3) develop possible sampling modes for the new MMCR processors to allow for adequate sampling of boundary layer clouds, and (4) retrieve updraft and downdraft structures under precipitating conditions.

  14. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, R.J.; Bible, D.W.; Paulauskas, F.L.

    1998-02-24

    A method for curing polymers incorporating a variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity is disclosed. By varying the frequency of the microwave signal, non-uniformities within the cavity are minimized, thereby achieving a more uniform cure throughout the workpiece. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. The furnace cavity may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing. 15 figs.

  15. Radiograph and passive data analysis using mixed variable optimization

    DOE Patents [OSTI]

    Temple, Brian A.; Armstrong, Jerawan C.; Buescher, Kevin L.; Favorite, Jeffrey A.

    2015-06-02

    Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography analysis. For example, certain embodiments perform radiographic analysis using mixed variable computation techniques. One exemplary system comprises a radiation source, a two-dimensional detector for detecting radiation transmitted through a object between the radiation source and detector, and a computer. In this embodiment, the computer is configured to input the radiographic image data from the two-dimensional detector and to determine one or more materials that form the object by using an iterative analysis technique that selects the one or more materials from hierarchically arranged solution spaces of discrete material possibilities and selects the layer interfaces from the optimization of the continuous interface data.

  16. Turbocharger with variable nozzle having vane sealing surfaces

    DOE Patents [OSTI]

    Arnold, Philippe (Hennecourt, FR); Petitjean, Dominique (Julienrupt, FR); Ruquart, Anthony (Thaon les Vosges, FR); Dupont, Guillaume (Thaon les Vosges, FR); Jeckel, Denis (Thaon les Vosges, FR)

    2011-11-15

    A variable nozzle for a turbocharger includes a plurality of vanes rotatably mounted on a nozzle ring and disposed in a nozzle flow path defined between the nozzle ring and an opposite nozzle wall. Either or both of the faces of the nozzle ring and nozzle wall include(s) at least one step that defines sealing surfaces positioned to be substantially abutted by airfoil surfaces of the vanes in the closed position of the vanes and to be spaced from the airfoil surfaces in positions other than the closed position. This substantial abutment between the airfoil surfaces and the sealing surfaces serves to substantially prevent exhaust gas from leaking past the ends of the airfoil portions. At the same time, clearances between the nozzle ring face and the end faces of the airfoil portions can be sufficiently large to prevent binding of the vanes under all operating conditions.

  17. Method for curing polymers using variable-frequency microwave heating

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); Bible, Don W. (Clinton, TN); Paulauskas, Felix L. (Oak Ridge, TN)

    1998-01-01

    A method for curing polymers (11) incorporating a variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34). By varying the frequency of the microwave signal, non-uniformities within the cavity (34) are minimized, thereby achieving a more uniform cure throughout the workpiece (36). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. The furnace cavity (34) may be adapted to be used to cure materials defining a continuous sheet or which require compressive forces during curing.

  18. The Kelastic variable wall mining machine. Interim final report

    SciTech Connect (OSTI)

    1995-11-12

    This machine cuts coal along a longwall face extending up to 500 feet by a rotating auger with bits. The machine also transports the coal that is cut acting as screw conveyor. By virtue of an integral shroud comprising part of the conveyor the machine is also amenable to a separation of the zones where men work from air being contaminated by dust and methane gas by the cutting action. Beginning as single intake air courses, the air separates at the working section where one split provides fresh air to the Occupied Zone (OZ) for human needs and the other split purges and carries away dust and methane from face fragmentation in the Cutting Zone (CZ). The attractiveness of the Variable Wall Mining Machine is that it addresses the limitations of current longwall mining equipment: it can consistently out-produce continuous mining machines and most longwall shearing machines. It also is amenable to configuring an environment, the dual-duct system, where the air for human breathing is separated from dust-laden ventilating air with methane mixtures. The objective of the research was to perform a mathematical and experimental study of the interrelationships of the components of the system so that a computer model could demonstrate the workings of the system in an animation program. The analysis resulted in the compilation of the parameters for three different configurations of a dual aircourse system of ventilating underground mines. In addressing the goal of an inherently safe mining system the dual-duct adaptation to the Variable Wall Mining Machine appears to offer the path to solution. The respirable dust problem is solvable; the explosive dust problem is nearly solvable; and the explosive methane problem can be greatly reduced. If installed in a highly gassy mine, the dual duct models would also be considerably less costly.

  19. Variable-metric diffraction crystals for x-ray optics

    SciTech Connect (OSTI)

    Smither, R.K.; Fernandez, P.B. )

    1992-02-01

    A variable-metric (VM) crystal is one in which the spacing between the crystalline planes changes with position in the crystal. This variation can be either parallel to the crystalline planes or perpendicular to the crystalline planes of interest and can be produced by either introducing a thermal gradient in the crystal or by growing a crystal made of two or more elements and changing the relative percentages of the two elements as the crystal is grown. A series of experiments were performed in the laboratory to demonstrate the principle of the variable-metric crystal and its potential use in synchrotron beam lines. One of the most useful applications of the VM crystal is to increase the number of photons per unit bandwidth in a diffracted beam without losing any of the overall intensity. In a normal synchrotron beam line that uses a two-crystal monochromator, the bandwidth of the diffracted photon beam is determined by the vertical opening angle of the beam which is typically 0.10--0.30 mrad or 20--60 arcsec. When the VM crystal approach is applied, the bandwidth of the beam can be made as narrow as the rocking curve of the diffracting crystal, which is typically 0.005--0.050 mrad or 1--10 arcsec. Thus a very large increase of photons per unit bandwidth (or per unit energy) can be achieved through the use of VM crystals. When the VM principle is used with bent crystals, new kinds of x-ray optical elements can be generated that can focus and defocus x-ray beams much like simple lenses where the focal length of the lens can be changed to match its application. Thus both large magnifications and large demagnifications can be achieved as well as parallel beams with narrow bandwidths.

  20. THE ENIGMATIC YOUNG, LOW-MASS VARIABLE TWA 30

    SciTech Connect (OSTI)

    Looper, Dagny L.; Rayner, John; Pitts, Mark A.; Mohanty, Subhanjoy; Bochanski, John J.; Burgasser, Adam J.; Mamajek, Eric E.; Herczeg, Gregory J.; West, Andrew A.; Faherty, Jacqueline K.; Kirkpatrick, J. Davy

    2010-05-01

    TWA 30 is a remarkable young (7 {+-} 3 Myr), low-mass (0.12 {+-} 0.04 M{sub sun}), late-type star (M5 {+-} 1) residing 42 {+-} 2 pc away from the Sun in the TW Hydrae Association (TWA). It shows strong outflow spectral signatures such as [S II], [O I], [O II], [O III], and Mg I], while exhibiting weak H{alpha} emission (-6.8 {+-} 1.2 A). Emission lines of [S II] and [O I] are common to T Tauri stars still residing in their natal molecular clouds, while [O III] and Mg I] emission lines are incredibly rare in this same population; in the case of TWA 30, these latter lines may arise from new outflow material colliding into older outflow fronts. The weak H{alpha} emission and small radial velocity shifts of line emission relative to the stellar frame of rest (generally {approx_lt}10 km s{sup -1}) suggest that the disk is viewed close to edge-on and that the stellar axis may be inclined to the disk, similar to the AA Tau system, based on its temporal changes in emission/absorption line strengths/profiles and variable reddening (A{sub V} = 1.5-9.0). The strong Li absorption (0.61 {+-} 0.13 A) and common kinematics with members of the TWA confirm its age and membership to the association. Given the properties of this system such as its proximity, low mass, remarkable outflow signatures, variability, and edge-on configuration, this system is a unique case study at a critical time in disk evolution and planet-building processes.

  1. A High Temperature Hermetic Primer and a Variable Spring Tester

    SciTech Connect (OSTI)

    Begeal, D.R.

    1994-05-01

    Percussion primers are used at Sandia to ignite energetic components such as pyrotechnic actuators and thermal batteries. This report describes a High Temperature Hermetic Primer (HTHP) that was developed to replace a previous G16 Percussion Primer Subassembly (Gl6PPS). The ignition mix in these primers is the same as in the discontinued Remington 44G16 (KC1O{sub 3}, SbS{sub 3}, and Ca{sub 2}Si). The HTHP has nearly the same sensitivity as the 44G16 and a significantly lower sensitivity than the G16PPS. In parallel with the HTHP development, we also designed a Variable Spring Tester (VST) to determine percussion primer ignition sensitivity with firing pins that have the same mass as those used in field applications. The tester is capable of accelerating firing pins over a velocity range of 100 to 600 inches per second for pins weighing up to 6 grams. The desired impulse can be preselected with an accuracy of better than {plus_minus}1%. The actual impulse is measured on every shot. The VST was characterized using the WW42Cl primer, as well as with the G16PPS and the HTHP. Compared to data from conventional ball drop testers, we found that ignition sensitivities were lower and there was less scatter in the sensitivity data. Our experiments indicate that ignition sensitivity is not strictly energy dependent, but also depends on the rate of deposition, or firing pin velocity in this case. Development results for the HTHP and Variable Spring Tester are discussed and design details are shown.

  2. Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review |

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

    Department of Energy Pump 2013 Peer Review Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review PDF icon Advanced Variable Speed Integrated Heat Pump - 2013 Peer Review Presentation More Documents & Publications Advanced variable-speed Air Source Integrated Heat Pump prototype system and field test site near Knoxville, TN Credit: Oak Ridge National Lab Advanced Variable Speed

  3. Detection of the Cosmic ?-Ray Horizon From Multiwavelength Observations of Blazars

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dominguez, A.; Finke, J. D.; Prada, F.; Primack, J. R.; Kitaura, F. S.; Siana, B.; Paneque, D.

    2013-05-24

    The first statistically significant detection of the cosmic ?-ray horizon (CGRH) that is independent of any extragalactic background light (EBL) model is presented. The CGRH is a fundamental quantity in cosmology. It gives an estimate of the opacity of the Universe to very high energy (VHE) ?-ray photons due to photon-photon pair production with the EBL. The only estimations of the CGRH to date are predictions from EBL models and lower limits from ?-ray observations of cosmological blazars and ?-ray bursts. Here, we present homogeneous synchrotron/synchrotron self-Compton (SSC) models of the spectral energy distributions of 15 blazars based on (almost)moresimultaneous observations from radio up to the highest energy ?-rays taken with the Fermi satellite. These synchrotron/SSC models predict the unattenuated VHE fluxes, which are compared with the observations by imaging atmospheric Cherenkov telescopes. This comparison provides an estimate of the optical depth of the EBL, which allows a derivation of the CGRH through a maximum likelihood analysis that is EBL-model independent. We find that the observed CGRH is compatible with the current knowledge of the EBL.less

  4. Understanding and Improving CRM and GCM Simulations of Cloud Systems with ARM Observations

    SciTech Connect (OSTI)

    Wu, Xiaoqing

    2014-02-25

    The works supported by this ASR project lay the solid foundation for improving the parameterization of convection and clouds in the NCAR CCSM and the climate simulations. We have made a significant use of CRM simulations and ARM observations to produce thermodynamically and dynamically consistent multi-year cloud and radiative properties; improve the GCM simulations of convection, clouds and radiative heating rate and fluxes using the ARM observations and CRM simulations; and understand the seasonal and annual variation of cloud systems and their impacts on climate mean state and variability. We conducted multi-year simulations over the ARM SGP site using the CRM with multi-year ARM forcing data. The statistics of cloud and radiative properties from the long-term CRM simulations were compared and validated with the ARM measurements and value added products (VAP). We evaluated the multi-year climate simulations produced by the GCM with the modified convection scheme. We used multi-year ARM observations and CRM simulations to validate and further improve the trigger condition and revised closure assumption in NCAR GCM simulations that demonstrate the improvement of climate mean state and variability. We combined the improved convection scheme with the mosaic treatment of subgrid cloud distributions in the radiation scheme of the GCM. The mosaic treatment of cloud distributions has been implemented in the GCM with the original convection scheme and enables the use of more realistic cloud amounts as well as cloud water contents in producing net radiative fluxes closer to observations. A physics-based latent heat (LH) retrieval algorithm was developed by parameterizing the physical linkages of observed hydrometeor profiles of cloud and precipitation to the major processes related to the phase change of atmospheric water.

  5. Fingerprints of anthropogenic and natural variability in global-mean surface temperature

    SciTech Connect (OSTI)

    Wallace, J.M.; Zhang, Yuan

    1997-11-01

    This paper presents an analysis designed to detect greenhouse warming by distinguishing between temperature rises induced by increasing atmospheric concentrations of greenhouse gases and those induced by background variability that are present without changes in atmospheric composition. The strategy is based on the surface temperature field. At each observation time, the projection of the anomalous temperature field on the presumed anthropogenic fingerprint is removed in order to obtain a temperature deviation field; i.e., the temperature anomalies in the phase space orthogonal to the anthropogenic fingerprint, which are presumed to be entirely natural. The time series of the expansion coefficients of the fingerprint a(t) is then regressed on this temperature deviation field to identify the axis in the orthogonal phase space along which the variations are most strongly correlated, and an index n(t) of the temporal variations along that axis is generated. The index a(t) is then regressed upon n(t) and the resulting least squares fit is regarded as the component of a(t) that can be ascribed to natural causes. The analysis was performed for monthly global surface temperature anomaly fields for the period 1900-95. Results indicate that two well defined patterns of natural variability contribute to variations in global mean temperature: the synthetic cold ocean-warm land (COWL) pattern and the El Nino-Southern Oscillation (ENSO). In domains that include surface air temperature over Eurasia and North America, the COWL pattern tends to be dominant. The ENSO signature emerges as the pattern most strongly linearly correlated with global sea surface temperature and with tropospheric layer-averaged temperatures. 24 refs., 3 figs.

  6. Head Observation Organizer (HObO)

    SciTech Connect (OSTI)

    Steven Predmore

    2008-03-06

    The Head Observation Organizer, HObO, is a computer program that stores and manages measured ground-water levels. HObO was developed to help ground-water modelers compile, manage, and document water-level data needed to calibrate ground-water models. Well-construction and water-level data from the U.S. Geological Survey National Water Database (NWIS) easily can be imported into HObO from the NWIS web site (NWISWeb). The water-level data can be flagged to determine which data will be included in the calibration data set. The utility program HObO_NWISWeb was developed to simplify the down loading of well and water-level data from NWISWeb. An ArcGIS NWISWeb Extension was developed to retrieve site information from NWISWeb. A tutorial is presented showing the basic elements of HObO.

  7. Global Volunteer Observing Ship (VOS) Program Data

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

    CDIAC provides data management support for the Global Volunteer Observing Ship (VOS) Program. The VOS project is coordinated by the UNESCO International Ocean Carbon Coordination Project (IOCCP). The international groups from 14 countries have been outfitting research ships and commercial vessels with automated CO2 sampling equipment to analyze the carbon exchange between the ocean and atmosphere. [copied from http://cdiac.ornl.gov/oceans/genInfo.html] CDIAC provides a map interface with the shipping routes of the 14 countries involved marked in different colors. Clicking on the ship's name on that route brings up information about the vessel, the kinds of measurements collected and the timeframe, links to project pages, and, most important, the links to the data files themselves. The 14 countries are: United States, United Kingdom, Japan, France, Germany, Australia, Canada, Spain, Norway, New Zealand, China (including Taiwan), Iceland, and the Netherlands. Both archived and current, underway data can be accessed from the CDIAC VOS page.

  8. Constraint effects observed in crack initiation stretch

    SciTech Connect (OSTI)

    Lambert, D.M.; Ernst, H.A.

    1995-12-31

    The current paper characterizes constraint in fracture: J-modified resistance (Jr) curves were developed for two tough structural materials, 6061-T651 (aluminum) and IN718-STA1 (nickel-base superalloy). A wide variety of configurations was tested to consider load configurations from bending to tension including three specimen types (compact tension, center-crack tension, and single-edge notched tension), and a range of ligament lengths and thicknesses, as well as side-grooved and smooth-sided ligaments. The Jr curves exhibited an inflection point after some crack extension, and the data were excluded beyond the inflection. Qualified Jr curves for the two materials showed similar behavior, but R-curves were identical for equal ligament length-to-thickness ratio (RL), for the aluminum alloy, with increasing slope for increasing RL, while for the nickel, the resistance curves aligned for equal ligament thickness, B, and the slope increased for decreasing B. Displacements at the original crack tip (CToD) were recorded throughout the test for several specimens. CToD-versus-crack extension curves were developed, and data were excluded beyond the inflection point (as with the Jr curves). The data collapsed into two distinct curves, thought to represent the surface, plane stress effect and the central, plane strain effect. This was observed for both materials. A technique called profiling is presented for the aluminum alloy only, where the crack face displacements are recorded at the final point of the test as a function of the position throughout the crack cavity, along with an effort to extract the observations in a usable form. Displacements were consistent throughout the cross-section at and behind the original crack tip. In the region where the crack grew, this displacement was developed by a combination of stretch and crack growth. The stretch required to initiate crack extension was a function of the depth beneath the surface into the cross-section.

  9. ELLIPSOIDAL VARIABLE V1197 ORIONIS: ABSOLUTE LIGHT-VELOCITY ANALYSIS FOR KNOWN DISTANCE

    SciTech Connect (OSTI)

    Wilson, R. E.; Chochol, D.; KomzIk, R.; Van Hamme, W.; Pribulla, T.; Volkov, I.

    2009-09-01

    V1197 Orionis light curves from a long-term observing program for red giant binaries show ellipsoidal variation of small amplitude in the V and R{sub C} bands, although not clearly in U and B. Eclipses are not detected. All four bands show large irregular intrinsic variations, including fleeting quasi-periodicities identified by power spectra, that degrade analysis and may be caused by dynamical tides generated by orbital eccentricity. To deal with the absence of eclipses and consequent lack of astrophysical and geometrical information, direct use is made of the Hipparcos parallax distance while the V and R{sub C} light curves and (older) radial velocity curves are analyzed simultaneously in terms of absolute flux. The red giant's temperature is estimated from new spectra. This type of analysis, called Inverse Distance Estimation for brevity, is new and can also be applied to other ellipsoidal variables. Advantages gained by utilization of definite distance and temperature are discussed in regard to how radius, fractional lobe filling, and mass ratio information are expressed in the observations. The advantages were tested in solutions of noisy synthetic data. Also discussed and tested by simulations are ideas on the optimal number of light curves to be solved simultaneously under various conditions. The dim companion has not been observed or discussed in the literature but most solutions find its mass to be well below that of the red giant. Solutions show red giant masses that are too low for evolution to the red giant stage within the age of the Galaxy, although that result is probably an artifact of the intrinsic brightness fluctuations.

  10. Black hole variability and the star formation-active galactic nucleus connection: Do all star-forming galaxies host an active galactic nucleus?

    SciTech Connect (OSTI)

    Hickox, Ryan C.; Chen, Chien-Ting J.; Civano, Francesca M.; Hainline, Kevin N.; Mullaney, James R.; Alexander, David M.; Goulding, Andy D.

    2014-02-10

    We investigate the effect of active galactic nucleus (AGN) variability on the observed connection between star formation and black hole accretion in extragalactic surveys. Recent studies have reported relatively weak correlations between observed AGN luminosities and the properties of AGN hosts, which has been interpreted to imply that there is no direct connection between AGN activity and star formation. However, AGNs may be expected to vary significantly on a wide range of timescales (from hours to Myr) that are far shorter than the typical timescale for star formation (?100 Myr). This variability can have important consequences for observed correlations. We present a simple model in which all star-forming galaxies host an AGN when averaged over ?100 Myr timescales, with long-term average AGN accretion rates that are perfectly correlated with the star formation rate (SFR). We show that reasonable prescriptions for AGN variability reproduce the observed weak correlations between SFR and L {sub AGN} in typical AGN host galaxies, as well as the general trends in the observed AGN luminosity functions, merger fractions, and measurements of the average AGN luminosity as a function of SFR. These results imply that there may be a tight connection between AGN activity and SFR over galaxy evolution timescales, and that the apparent similarities in rest-frame colors, merger rates, and clustering of AGNs compared to 'inactive' galaxies may be due primarily to AGN variability. The results provide motivation for future deep, wide extragalactic surveys that can measure the distribution of AGN accretion rates as a function of SFR.

  11. The spectral variability of the GHZ-Peaked spectrum radio source PKS 1718-649 and a comparison of absorption models

    SciTech Connect (OSTI)

    Tingay, S. J.; Macquart, J.-P.; Wayth, R. B.; Trott, C. M.; Emrich, D.; Collier, J. D.; Wong, G. F.; Rees, G.; Stevens, J.; Carretti, E.; Callingham, J. R.; Gaensler, B. M.; McKinley, B.; Briggs, F.; Bernardi, G.; Bowman, J. D.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; Goeke, R.; and others

    2015-02-01

    Using the new wideband capabilities of the ATCA, we obtain spectra for PKS 1718-649, a well-known gigahertz-peaked spectrum radio source. The observations, between approximately 1 and 10 GHz over 3 epochs spanning approximately 21 months, reveal variability both above the spectral peak at ∼3 GHz and below the peak. The combination of the low- and high-frequency variability cannot be easily explained using a single absorption mechanism, such as free–free absorption or synchrotron self-absorption. We find that the PKS 1718-649 spectrum and its variability are best explained by variations in the free–free optical depth on our line of sight to the radio source at low frequencies (below the spectral peak) and the adiabatic expansion of the radio source itself at high frequencies (above the spectral peak). The optical depth variations are found to be plausible when X-ray continuum absorption variability seen in samples of active galactic nuclei is considered. We find that the cause of the peaked spectrum in PKS 1718-649 is most likely due to free–free absorption. In agreement with previous studies, we find that the spectrum at each epoch of observation is best fit by a free–free absorption model characterized by a power-law distribution of free–free absorbing clouds. This agreement is extended to frequencies below the 1 GHz lower limit of the ATCA by considering new observations with Parkes at 725 MHz and 199 MHz observations with the newly operational Murchison Widefield Array. These lower frequency observations argue against families of absorption models (both free–free and synchrotron self-absorption) that are based on simple homogenous structures.

  12. Observations of the scale-dependent turbulence and evaluation of the flux–gradient relationship for sensible heat for a closed Douglas-fir canopy in very weak wind conditions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Vickers, D.; Thomas, C. K.

    2014-09-16

    Observations of the scale-dependent turbulent fluxes, variances, and the bulk transfer parameterization for sensible heat above, within, and beneath a tall closed Douglas-fir canopy in very weak winds are examined. The daytime sub-canopy vertical velocity spectra exhibit a double-peak structure with peaks at timescales of 0.8 s and 51.2 s. A double-peak structure is also observed in the daytime sub-canopy heat flux co-spectra. The daytime momentum flux co-spectra in the upper bole space and in the sub-canopy are characterized by a relatively large cross-wind component, likely due to the extremely light and variable winds, such that the definition of amore »mean wind direction, and subsequent partitioning of the momentum flux into along- and cross-wind components, has little physical meaning. Positive values of both momentum flux components in the sub-canopy contribute to upward transfer of momentum, consistent with the observed sub-canopy secondary wind speed maximum. For the smallest resolved scales in the canopy at nighttime, we find increasing vertical velocity variance with decreasing timescale, consistent with very small eddies possibly generated by wake shedding from the canopy elements that transport momentum, but not heat. Unusually large values of the velocity aspect ratio within the canopy were observed, consistent with enhanced suppression of the horizontal wind components compared to the vertical by the very dense canopy. The flux–gradient approach for sensible heat flux is found to be valid for the sub-canopy and above-canopy layers when considered separately in spite of the very small fluxes on the order of a few W m−2 in the sub-canopy. However, single-source approaches that ignore the canopy fail because they make the heat flux appear to be counter-gradient when in fact it is aligned with the local temperature gradient in both the sub-canopy and above-canopy layers. While sub-canopy Stanton numbers agreed well with values typically reported in the literature, our estimates for the above-canopy Stanton number were much larger, which likely leads to underestimated modeled sensible heat fluxes above dark warm closed canopies.« less

  13. VARIABLE FIRING RATE OIL BURNER USING PULSE FUEL FLOW CONTROL.

    SciTech Connect (OSTI)

    KRISHNA,C.R.; BUTCHER,T.A.; KAMATH,B.R.

    2004-10-01

    The residential oil burner market is currently dominated by the pressure-atomized retention head burner, which has an excellent reputation for reliability and efficiency. In this burner, oil is delivered to a fuel nozzle at pressures from 100 to 150 psi. In addition, to atomizing the fuel, the small, carefully controlled size of the nozzle exit orifice serves to control the burner firing rate. Burners of this type are currently available at firing rates of more than 0.5 gallons-per-hour (70,000 Btu/hr). Nozzles have been made for lower firing rates, but experience has shown that such nozzles suffer rapid fouling of the necessarily small passages, leading to bad spray patterns and poor combustion performance. Also, traditionally burners and the nozzles are oversized to exceed the maximum demand. Typically, this is figured as follows. The heating load of the house on the coldest day for the location is considered to define the maximum heat load. The contractor or installer adds to this to provide a safety margin and for future expansion of the house. If the unit is a boiler that provides domestic hot water through the use of a tankless heating coil, the burner capacity is further increased. On the contrary, for a majority of the time, the heating system is satisfying a much smaller load, as only rarely do all these demands add up. Consequently, the average output of the heating system has to be much less than the design capacity and this is accomplished by start and stop cycling operation of the system so that the time-averaged output equals the demand. However, this has been demonstrated to lead to overall efficiencies lower than the steady-state efficiency. Therefore, the two main reasons for the current practice of using oil burners much larger than necessary for space heating are the unavailability of reliable low firing rate oil burners and the desire to assure adequate input rate for short duration, high draw domestic hot water loads. One approach to solve this problem is to develop a burner, which can operate at two firing rates, with the lower rate being significantly lower than 0.5 gallons per hour. This paper describes the initial results of adopting this approach through a pulsed flow nozzle. It has been shown that the concept of flow modulation with a small solenoid valve is feasible. Especially in the second configuration tested, where the Lee valve was integrated with the nozzle, reasonable modulation in flow of the order of 1.7 could be achieved. For this first prototype, the combustion performance is still not quite satisfactory. Improvements in operation, for example by providing a sharp and positive shut-off so that there is no flow under low pressures with consequent poor atomization could lead to better combustion performance. This could be achieved by using nozzles that have shut off or check valves for example. It is recommended that more work in cooperation with the valve manufacturer could produce a technically viable system. Marketability is of course a far more complex problem to be addressed once a technically viable product is available.

  14. LARGE-SCALE PERIODIC VARIABILITY OF THE WIND OF THE WOLF-RAYET STAR WR 1 (HD 4004)

    SciTech Connect (OSTI)

    Chene, A.-N.

    2010-06-20

    We present the results of an intensive photometric and spectroscopic monitoring campaign of the WN4 Wolf-Rayet (WR) star WR 1 = HD 4004. Our broadband V photometry covering a timespan of 91 days shows variability with a period of P = 16.9{sup +0.6}{sub -0.3} days. The same period is also found in our spectral data. The light curve is non-sinusoidal with hints of a gradual change in its shape as a function of time. The photometric variations nevertheless remain coherent over several cycles and we estimate that the coherence timescale of the light curve is of the order of 60 days. The spectroscopy shows large-scale line-profile variability which can be interpreted as excess emission peaks moving from one side of the profile to the other on a timescale of several days. Although we cannot unequivocally exclude the unlikely possibility that WR 1 is a binary, we propose that the nature of the variability we have found strongly suggests that it is due to the presence in the wind of the WR star of large-scale structures, most likely corotating interaction regions (CIRs), which are predicted to arise in inherently unstable radiatively driven winds when they are perturbed at their base. We also suggest that variability observed in WR 6, WR 134, and WR 137 is of the same nature. Finally, assuming that the period of CIRs is related to the rotational period, we estimate the rotation rate of the four stars for which sufficient monitoring has been carried out, i.e., v{sub rot} = 6.5, 40, 70, and 275 km s{sup -1} for WR 1, WR 6, WR 134, and WR 137, respectively.

  15. System and method of modulating electrical signals using photoconductive wide bandgap semiconductors as variable resistors

    DOE Patents [OSTI]

    Harris, John Richardson; Caporaso, George J; Sampayan, Stephen E

    2013-10-22

    A system and method for producing modulated electrical signals. The system uses a variable resistor having a photoconductive wide bandgap semiconductor material construction whose conduction response to changes in amplitude of incident radiation is substantially linear throughout a non-saturation region to enable operation in non-avalanche mode. The system also includes a modulated radiation source, such as a modulated laser, for producing amplitude-modulated radiation with which to direct upon the variable resistor and modulate its conduction response. A voltage source and an output port, are both operably connected to the variable resistor so that an electrical signal may be produced at the output port by way of the variable resistor, either generated by activation of the variable resistor or propagating through the variable resistor. In this manner, the electrical signal is modulated by the variable resistor so as to have a waveform substantially similar to the amplitude-modulated radiation.

  16. Observational tests for ?(t)CDM cosmology

    SciTech Connect (OSTI)

    Pigozzo, C.; Carneiro, S.; Dantas, M.A.; Alcaniz, J.S. E-mail: aldinez@on.br E-mail: alcaniz@on.br

    2011-08-01

    We investigate the observational viability of a class of cosmological models in which the vacuum energy density decays linearly with the Hubble parameter, resulting in a production of cold dark matter particles at late times. Similarly to the flat ?CDM case, there is only one free parameter to be adjusted by the data in this class of ?(t)CDM scenarios, namely, the matter density parameter. To perform our analysis we use three of the most recent SNe Ia compilation sets (Union2, SDSS and Constitution) along with the current measurements of distance to the BAO peaks at z = 0.2 and z = 0.35 and the position of the first acoustic peak of the CMB power spectrum. We show that in terms of ?{sup 2} statistics both models provide good fits to the data and similar results. A quantitative analysis discussing the differences in parameter estimation due to SNe light-curve fitting methods (SALT2 and MLCS2k2) is studied using the current SDSS and Constitution SNe Ia compilations. A matter power spectrum analysis using the 2dFGRS is also performed, providing a very good concordance with the constraints from the SDSS and Constitution MLCS2k2 data.

  17. Optical monitor for observing turbulent flow

    DOE Patents [OSTI]

    Albrecht, Georg F. (Livermore, CA); Moore, Thomas R. (Rochester, NY)

    1992-01-01

    The present invention provides an apparatus and method for non-invasively monitoring turbulent fluid flows including anisotropic flows. The present invention uses an optical technique to filter out the rays travelling in a straight line, while transmitting rays with turbulence induced fluctuations in time. The output is two dimensional, and can provide data regarding the spectral intensity distribution, or a view of the turbulence in real time. The optical monitor of the present invention comprises a laser that produces a coherent output beam that is directed through a fluid flow, which phase-modulates the beam. The beam is applied to a temporal filter that filters out the rays in the beam that are straight, while substantially transmitting the fluctuating, turbulence-induced rays. The temporal filter includes a lens and a photorefractive crystal such as BaTiO.sub.3 that is positioned in the converging section of the beam near the focal plane. An imaging system is used to observe the filtered beam. The imaging system may take a photograph, or it may include a real time camera that is connected to a computer. The present invention may be used for many purposes including research and design in aeronautics, hydrodynamics, and combustion.

  18. Mechanisms and observations of coronal dimming for the 201 August 7 event

    SciTech Connect (OSTI)

    Mason, James Paul; Woods, T. N.; Caspi, A.; Thompson, B. J.; Hock, R. A.

    2014-07-01

    Coronal dimming of extreme ultraviolet (EUV) emission has the potential to be a useful forecaster of coronal mass ejections (CMEs). As emitting material leaves the corona, a temporary void is left behind which can be observed in spectral images and irradiance measurements. The velocity and mass of the CMEs should impact the character of those observations. However, other physical processes can confuse the observations. We describe these processes and the expected observational signature, with special emphasis placed on the differences. We then apply this understanding to a coronal dimming event with an associated CME that occurred on 2010 August 7. Data from the Solar Dynamics Observatory's Atmospheric Imaging Assembly and EUV Variability Experiment (EVE) are used for observations of the dimming, while the Solar and Heliospheric Observatory's Large Angle and Spectrometric Coronagraph and the Solar Terrestrial Relations Observatory's COR1 and COR2 are used to obtain velocity and mass estimates for the associated CME. We develop a technique for mitigating temperature effects in coronal dimming from full-disk irradiance measurements taken by EVE. We find that for this event, nearly 100% of the dimming is due to mass loss in the corona.

  19. Feasibility of wavelet expansion methods to treat the energy variable

    SciTech Connect (OSTI)

    Van Rooijen, W. F. G.

    2012-07-01

    This paper discusses the use of the Discrete Wavelet Transform (DWT) to implement a functional expansion of the energy variable in neutron transport. The motivation of the work is to investigate the possibility of adapting the expansion level of the neutron flux in a material region to the complexity of the cross section in that region. If such an adaptive treatment is possible, 'simple' material regions (e.g., moderator regions) require little effort, while a detailed treatment is used for 'complex' regions (e.g., fuel regions). Our investigations show that in fact adaptivity cannot be achieved. The most fundamental reason is that in a multi-region system, the energy dependence of the cross section in a material region does not imply that the neutron flux in that region has a similar energy dependence. If it is chosen to sacrifice adaptivity, then the DWT method can be very accurate, but the complexity of such a method is higher than that of an equivalent hyper-fine group calculation. The conclusion is thus that, unfortunately, the DWT approach is not very practical. (authors)

  20. Electromagnetic variable degrees of freedom actuator systems and methods

    DOE Patents [OSTI]

    Montesanti, Richard C. (Pleasanton, CA); Trumper, David L. (Plaistow, NH); Kirtley, Jr., James L. (Brookline, MA)

    2009-02-17

    The present invention provides a variable reluctance actuator system and method that can be adapted for simultaneous rotation and translation of a moving element by applying a normal-direction magnetic flux on the moving element. In a beneficial example arrangement, the moving element includes a swing arm that carries a cutting tool at a set radius from an axis of rotation so as to produce a rotary fast tool servo that provides a tool motion in a direction substantially parallel to the surface-normal of a workpiece at the point of contact between the cutting tool and workpiece. An actuator rotates a swing arm such that a cutting tool moves toward and away from a mounted rotating workpiece in a controlled manner in order to machine the workpiece. Position sensors provide rotation and displacement information for a swing arm to a control system. A control system commands and coordinates motion of the fast tool servo with the motion of a spindle, rotating table, cross-feed slide, and in feed slide of a precision lathe.

  1. Variable current speed controller for eddy current motors

    DOE Patents [OSTI]

    Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

    1982-03-12

    A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

  2. Method and apparatus for controlling continuously variable transmission for vehicle

    SciTech Connect (OSTI)

    Osanai, A.; Niwa, T.; Gono, T.

    1987-04-14

    A method is described of controlling a speed ratio of a continuously variable transmission for a vehicle for transmitting a rotary motion of an engine of the vehicle to drive wheels of the vehicle with a stepless speed change. The speed ratio of the transmission is regulated such that an actual speed of the engine coincides with a target engine speed. The method comprises: determining a first target speed of the engine based on a predetermined currently required output of the engine and according to a predetermined relation between the first target speed of the engine and the required output of the engine. The first target speed of the engine is normally used as the target engine speed to regulate the speed ratio of the transmission; detecting a running speed of the vehicle; and determining a second target speed of the engine based on a predetermined transmission efficiency of the transmission and on the first target speed of the engine. The second target speed of the engine is lower than the first target speed.

  3. The identification of extreme asymptotic giant branch stars and red supergiants in M33 with 24??m variability

    SciTech Connect (OSTI)

    Montiel, Edward J.; Clayton, Geoffrey C.; Johnson, Christopher B.; Srinivasan, Sundar; Engelbracht, Charles W.

    2015-02-01

    We present the first detection of 24 ?m variability in 24 sources in the Local Group galaxy M33. These results are based on 4 epochs of Multiband Imaging Photometer for Spitzer observations, which are irregularly spaced over ?750 days. We find that these sources are constrained exclusively to the Holmberg radius of the galaxy, which increases their chances of being members of M33. We have constructed spectral energy distributions (SEDs) ranging from the optical to the submillimeter to investigate the nature of these objects. We find that 23 of our objects are most likely heavily self-obscured, evolved stars, while the remaining source is the Giant H ii region, NGC 604. We believe that the observed variability is the intrinsic variability of the central star reprocessed through their circumstellar dust shells. Radiative transfer modeling was carried out to determine their likely chemical composition, luminosity, and dust production rate (DPR). As a sample, our modeling has determined an average luminosity of (3.80.9)10{sup 4} L{sub ?} and a total DPR of (2.30.1)10{sup ?5} M{sub ?} yr{sup ?1}. Most of the sources, given the high DPRs and short wavelength obscuration, are likely extreme asymptotic giant branch (XAGB) stars. Five of the sources are found to have luminosities above the classical AGB limit (M{sub bol} 54,000 L{sub ?}), which classifies them as probable red supergiants (RSGs). Almost all of the sources are classified as oxygen-rich. As also seen in the LMC, a significant fraction of the dust in M33 is produced by a handful of XAGB and RSG stars.

  4. Effects from influent boundary conditions on tracer migration and spatial variability features in intermediate-scale experiments

    SciTech Connect (OSTI)

    Fuentes, H.R.; Polzer, W.L.; Springer, E.P.

    1987-04-01

    In previous unsaturated transport studies at Los Alamos dispersion coefficients were estimated to be higher close to the tracer source than at greater distances from the source. Injection of tracers through discrete influent outlets could have accounted for those higher dispersions. Also, a lack of conservation of mass of the tracers was observed and suspected to be due to spatial variability in transport. In the present study experiments were performed under uniform influent (ponded) conditions in which breakthrough of tracers was monitored at four locations at each of four depths. All other conditions were similar to those of the unsaturated transport experiments. A comparison of results from these two sets of experiments indicates differences in the parameter estimates. Estimates were made for the dispersion coefficient and the retardation factor by the one-dimensional steady flow computer code, CFITIM. Estimates were also made for mass and for velocity and the dispersion coefficient by the method of moments. The dispersion coefficient decreased with depth under discrete influent application and increased with depth under ponded influent application. Retardation was predicted better under the discrete influent application than under ponded influent application. Differences in breakthroughs and in estimated parameters among locations at the same depth were observed under ponded influent application. Those differences indicate that there is a lack of conservation of mass as well as significant spatial variability across the experimental domain. 14 refs., 9 figs., 8 tabs.

  5. RECONCILING THE OBSERVED STAR-FORMING SEQUENCE WITH THE OBSERVED STELLAR MASS FUNCTION

    SciTech Connect (OSTI)

    Leja, Joel; Van Dokkum, Pieter G.; Franx, Marijn; Whitaker, Katherine E.

    2015-01-10

    We examine the connection between the observed star-forming sequence (SFR ? M {sup ?}) and the observed evolution of the stellar mass function in the range 0.2 < z < 2.5. We find that the star-forming sequence cannot have a slope ? ? 0.9 at all masses and redshifts because this would result in a much higher number density at 10 < log (M/M {sub ?}) < 11 by z = 1 than is observed. We show that a transition in the slope of the star-forming sequence, such that ? = 1 at log (M/M {sub ?}) < 10.5 and ? = 0.7-0.13z (Whitaker et al.) at log (M/M {sub ?}) > 10.5, greatly improves agreement with the evolution of the stellar mass function. We then derive a star-forming sequence that reproduces the evolution of the mass function by design. This star-forming sequence is also well described by a broken power law, with a shallow slope at high masses and a steep slope at low masses. At z = 2, it is offset by ?0.3 dex from the observed star-forming sequence, consistent with the mild disagreement between the cosmic star formation rate (SFR) and recent observations of the growth of the stellar mass density. It is unclear whether this problem stems from errors in stellar mass estimates, errors in SFRs, or other effects. We show that a mass-dependent slope is also seen in other self-consistent models of galaxy evolution, including semianalytical, hydrodynamical, and abundance-matching models. As part of the analysis, we demonstrate that neither mergers nor hidden low-mass quiescent galaxies are likely to reconcile the evolution of the mass function and the star-forming sequence. These results are supported by observations from Whitaker et al.

  6. Petroleum production at Maximum Efficient Rate Naval Petroleum Reserve No. 1 (Elk Hills), Kern County, California. Final Supplemental Environmental Impact Statement

    SciTech Connect (OSTI)

    Not Available

    1993-07-01

    This document provides an analysis of the potential impacts associated with the proposed action, which is continued operation of Naval Petroleum Reserve No. I (NPR-1) at the Maximum Efficient Rate (MER) as authorized by Public law 94-258, the Naval Petroleum Reserves Production Act of 1976 (Act). The document also provides a similar analysis of alternatives to the proposed action, which also involve continued operations, but under lower development scenarios and lower rates of production. NPR-1 is a large oil and gas field jointly owned and operated by the federal government and Chevron U.SA Inc. (CUSA) pursuant to a Unit Plan Contract that became effective in 1944; the government`s interest is approximately 78% and CUSA`s interest is approximately 22%. The government`s interest is under the jurisdiction of the United States Department of Energy (DOE). The facility is approximately 17,409 acres (74 square miles), and it is located in Kern County, California, about 25 miles southwest of Bakersfield and 100 miles north of Los Angeles in the south central portion of the state. The environmental analysis presented herein is a supplement to the NPR-1 Final Environmental Impact Statement of that was issued by DOE in 1979 (1979 EIS). As such, this document is a Supplemental Environmental Impact Statement (SEIS).

  7. Relaxation and critical strain for maximum In incorporation in AlInGaN on GaN grown by metal organic vapour phase epitaxy

    SciTech Connect (OSTI)

    Reuters, Benjamin; Finken, M.; Wille, A.; Kalisch, H.; Vescan, A.; Hollaender, B.; Heuken, M.

    2012-11-01

    Quaternary AlInGaN layers were grown on conventional GaN buffer layers on sapphire by metal organic vapour phase epitaxy at different surface temperatures and different reactor pressures with constant precursor flow conditions. A wide range in compositions within 30-62% Al, 5-29% In, and 23-53% Ga was covered, which leads to different strain states from high tensile to high compressive. From high-resolution x-ray diffraction and Rutherford backscattering spectrometry, we determined the compositions, strain states, and crystal quality of the AlInGaN layers. Atomic force microscopy measurements were performed to characterize the surface morphology. A critical strain value for maximum In incorporation near the AlInGaN/GaN interface is presented. For compressively strained layers, In incorporation is limited at the interface as residual strain cannot exceed an empirical critical value of about 1.1%. Relaxation occurs at about 15 nm thickness accompanied by strong In pulling. Tensile strained layers can be grown pseudomorphically up to 70 nm at a strain state of 0.96%. A model for relaxation in compressively strained AlInGaN with virtual discrete sub-layers, which illustrates the gradually changing lattice constant during stress reduction is presented.

  8. EARLY OBSERVATIONS AND ANALYSIS OF THE TYPE Ia SN 2014J IN M82

    SciTech Connect (OSTI)

    Marion, G. H.; Vink, J. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Sand, D. J. [Physics Department, Texas Tech University, Lubbock, TX 79409 (United States); Hsiao, E. Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Banerjee, D. P. K.; Joshi, V.; Venkataraman, V.; Ashok, N. M. [Astronomy and Astrophysics Division, Physical Research Laboratory, Navrangapura, Ahmedabad - 380009, Gujarat (India); Valenti, S.; Howell, D. A. [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States); Stritzinger, M. D. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Amanullah, R.; Johansson, J. [The Oskar Klein Centre, Physics Department, Stockholm University, Albanova University Center, SE 106 91 Stockholm (Sweden); Binzel, R. P. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Bochanski, J. J. [Haverford College, 370 Lancaster Avenue, Haverford, PA 19041 (United States); Bryngelson, G. L. [Department of Physics and Astronomy, Francis Marion University, 4822 East Palmetto Street, Florence, SC 29506 (United States); Burns, C. R. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Drozdov, D. [Department of Physics and Astronomy, Clemson University, 8304 University Station, Clemson, SC 29634 (United States); Fieber-Beyer, S. K. [Department of Space Studies, University of North Dakota, University Stop 9008, ND 58202 (United States); Graham, M. L., E-mail: hman@astro.as.utexas.edu [Astronomy Department, University of California at Berkeley, Berkeley, CA 94720 (United States); and others

    2015-01-01

    We present optical and near infrared (NIR) observations of the nearby Type Ia SN 2014J. Seventeen optical and 23 NIR spectra were obtained from 10days before (10d) to 10days after (+10d) the time of maximum B-band brightness. The relative strengths of absorption features and their patterns of development can be compared at one day intervals throughout most of this period. Carbon is not detected in the optical spectra, but we identify C I?1.0693 in the NIR spectra. Mg II lines with high oscillator strengths have higher initial velocities than other Mg II lines. We show that the velocity differences can be explained by differences in optical depths due to oscillator strengths. The spectra of SN 2014J show that it is a normal SN Ia, but many parameters are near the boundaries between normal and high-velocity subclasses. The velocities for O I, Mg II, Si II, S II, Ca II, and Fe II suggest that SN 2014J has a layered structure with little or no mixing. That result is consistent with the delayed detonation explosion models. We also report photometric observations, obtained from 10d to +29d, in the UBVRIJH and K{sub s} bands. The template fitting package SNooPy is used to interpret the light curves and to derive photometric parameters. Using R{sub V} = 1.46, which is consistent with previous studies, SNooPy finds that A{sub V} = 1.80 for E(B V){sub host} = 1.23 0.06 mag. The maximum B-band brightness of 19.19 0.10 mag was reached on February 1.74 UT 0.13days and the supernova has a decline parameter, ?m {sub 15}, of 1.12 0.02 mag.

  9. The effect of variable atmospheric forcing on oceanic subduction of a passive tracer in a numerical model: Implications for global warming

    SciTech Connect (OSTI)

    Horsfall, F.; Bleck, R.; Hanson, H.P.

    1997-11-01

    This study addresses the issue of the ocean`s response to the changing climate. The objectives is to determine the effect of variable atmospheric forcing on the ocean on decadal time scales, specifically on the subduction of a passive tracer. In the context of the model used in this study, this tracer is {open_quotes}tagged{close_quotes} water that is subducted into the thermocline and into the deep ocean. The model used in this study is the Miami Isopycnic Coordinate Ocean Model which has a realistic Atlantic domain from 20{degrees}S to 60{degrees}N. There are twelve model layers, the first (top) layer being the thermodynamically active mixed layer and the lower eleven layers all having constant potential density ({sigma}{sub {theta}}). The atmospheric forcing changes vary latitudinally, allowing for a maximum increase in wind at midlatitudes and a maximum increase in temperature at the poles. In these experiments, it was found that wind speed and temperature effects dominate in bringing about changes in mixed-layer depth and in tracer penetration at high latitudes, with wind speed effects having the greater weight. It is apparent from the results that the weakening of the North Atlantic thermohaline circulation is dependent on the atmospheric changes in air temperature and in the wind field. 11 refs., 2 figs.

  10. Variability of Battery Wear in Light Duty Plug-In Electric Vehicles Subject to Ambient Temperature, Battery Size, and Consumer Usage: Preprint

    SciTech Connect (OSTI)

    Wood, E.; Neubauer, J.; Brooker, A. D.; Gonder, J.; Smith, K. A.

    2012-08-01

    Battery wear in plug-in electric vehicles (PEVs) is a complex function of ambient temperature, battery size, and disparate usage. Simulations capturing varying ambient temperature profiles, battery sizes, and driving patterns are of great value to battery and vehicle manufacturers. A predictive battery wear model developed by the National Renewable Energy Laboratory captures the effects of multiple cycling and storage conditions in a representative lithium chemistry. The sensitivity of battery wear rates to ambient conditions, maximum allowable depth-of-discharge, and vehicle miles travelled is explored for two midsize vehicles: a battery electric vehicle (BEV) with a nominal range of 75 mi (121 km) and a plug-in hybrid electric vehicle (PHEV) with a nominal charge-depleting range of 40 mi (64 km). Driving distance distributions represent the variability of vehicle use, both vehicle-to-vehicle and day-to-day. Battery wear over an 8-year period was dominated by ambient conditions for the BEV with capacity fade ranging from 19% to 32% while the PHEV was most sensitive to maximum allowable depth-of-discharge with capacity fade ranging from 16% to 24%. The BEV and PHEV were comparable in terms of petroleum displacement potential after 8 years of service, due to the BEV?s limited utility for accomplishing long trips.

  11. Site-specific variability in BTEX biodegradation under denitrifying conditions

    SciTech Connect (OSTI)

    Kao, C.M.; Borden, R.C.

    1997-03-01

    Laboratory microcosm experiments were conducted to evaluate the feasibility of benzene, toluene, ethylbenzene, m-xylene, and o-xylene (BTEX) biodegradation under denitrifying conditions. Nine different sources of inocula, including contaminated and uncontaminated soil cores from four different sites and activated sludge, were used to establish microcosms. BTEX was not degraded under denitrifying conditions in microcosms inoculated with aquifer material from Rocky Point and Traverse City. However, rapid depletion of glucose under denitrifying conditions was observed in microcosms containing Rocky Point aquifer material. TEX degradation was observed in microcosms containing Rocky Point aquifer material. TEX degradation was observed in microcosms containing aquifer material from Fort Bragg and Sleeping Bear Dunes and sewage sludge. Benzene was recalcitrant in all microcosms tested. The degradation of o-xylene ceased after toluene, ethylbenzene, and m-xylene were depleted in the Fort Bragg and sludge microcosms, but o-xylene continued to degrade in microcosms with contaminated Sleeping Bear Dunes soil. The most probable number (MPN) of denitrifiers in these nine different inocula were measured using a microtiter technique. There was no correlation between the MPN of denitrifiers and the TEX degradation rate under denitrifying conditions. Experimental results indicate that the degradation sequence and TEX degradation rate under denitrifying conditions may differ among sites. Results also indicate that denitrification alone may not be a suitable bioremediation technology for gasoline-contaminated aquifers because of the inability of denitrifiers to degrade benzene.

  12. SWIFT X-RAY OBSERVATIONS OF CLASSICAL NOVAE. II. THE SUPER SOFT SOURCE SAMPLE

    SciTech Connect (OSTI)

    Schwarz, Greg J.; Ness, Jan-Uwe; Osborne, J. P.; Page, K. L.; Evans, P. A.; Beardmore, A. P.; Walter, Frederick M.; Andrew Helton, L.; Woodward, Charles E.; Bode, Mike; Starrfield, Sumner; Drake, Jeremy J.

    2011-12-01

    The Swift gamma-ray burst satellite is an excellent facility for studying novae. Its rapid response time and sensitive X-ray detector provides an unparalleled opportunity to investigate the previously poorly sampled evolution of novae in the X-ray regime. This paper presents Swift observations of 52 Galactic/Magellanic Cloud novae. We included the X-Ray Telescope (0.3-10 keV) instrument count rates and the UltraViolet and Optical Telescope (1700-8000 A) filter photometry. Also included in the analysis are the publicly available pointed observations of 10 additional novae the X-ray archives. This is the largest X-ray sample of Galactic/Magellanic Cloud novae yet assembled and consists of 26 novae with Super Soft X-ray emission, 19 from Swift observations. The data set shows that the faster novae have an early hard X-ray phase that is usually missing in slower novae. The Super Soft X-ray phase occurs earlier and does not last as long in fast novae compared to slower novae. All the Swift novae with sufficient observations show that novae are highly variable with rapid variability and different periodicities. In the majority of cases, nuclear burning ceases less than three years after the outburst begins. Previous relationships, such as the nuclear burning duration versus t{sub 2} or the expansion velocity of the eject and nuclear burning duration versus the orbital period, are shown to be poorly correlated with the full sample indicating that additional factors beyond the white dwarf mass and binary separation play important roles in the evolution of a nova outburst. Finally, we confirm two optical phenomena that are correlated with strong, soft X-ray emission which can be used to further increase the efficiency of X-ray campaigns.

  13. Hubble space telescope and ground-based observations of the type Iax supernovae SN 2005hk and SN 2008A

    SciTech Connect (OSTI)

    McCully, Curtis; Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Foley, Ryan J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Chornock, Ryan [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Holtzman, Jon A. [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Balam, David D. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Branch, David [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Filippenko, Alexei V.; Ganeshalingam, Mohan; Li, Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Frieman, Joshua [Kavli Institute for Cosmological Physics and Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Fynbo, Johan; Leloudas, Giorgos [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Galbany, Lluis [Institut de Fsica d'Altes Energies, Universitat Autnoma de Barcelona, E-08193 Bellaterra (Barcelona) (Spain); Garnavich, Peter M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Leonard, Douglas C., E-mail: cmccully@physics.rutgers.edu [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); and others

    2014-05-10

    We present Hubble Space Telescope (HST) and ground-based optical and near-infrared observations of SN 2005hk and SN 2008A, typical members of the Type Iax class of supernovae (SNe). Here we focus on late-time observations, where these objects deviate most dramatically from all other SN types. Instead of the dominant nebular emission lines that are observed in other SNe at late phases, spectra of SNe 2005hk and 2008A show lines of Fe II, Ca II, and Fe I more than a year past maximum light, along with narrow [Fe II] and [Ca II] emission. We use spectral features to constrain the temperature and density of the ejecta, and find high densities at late times, with n{sub e} ? 10{sup 9} cm{sup 3}. Such high densities should yield enhanced cooling of the ejecta, making these objects good candidates to observe the expected 'infrared catastrophe', a generic feature of SN Ia models. However, our HST photometry of SN 2008A does not match the predictions of an infrared catastrophe. Moreover, our HST observations rule out a 'complete deflagration' that fully disrupts the white dwarf for these peculiar SNe, showing no evidence for unburned material at late times. Deflagration explosion models that leave behind a bound remnant can match some of the observed properties of SNe Iax, but no published model is consistent with all of our observations of SNe 2005hk and 2008A.

  14. Long term observations of B2 1215+30 with veritas

    SciTech Connect (OSTI)

    Aliu, E.; Errando, M.; Archambault, S.; Arlen, T.; Aune, T.; Beilicke, M.; Buckley, J. H.; Bugaev, V.; Benbow, W.; Bird, R.; Bouvier, A.; Cesarini, A.; Connolly, M. P.; Ciupik, L.; Cui, W.; Feng, Q.; Finley, J. P.; Dumm, J.; Falcone, A.; Federici, S.; Collaboration: VERITAS collaboration; and others

    2013-12-20

    We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHEs; E > 100 GeV) by VERITAS with a significance of 8.9? and showed clear variability on timescales larger than months. In 2011, the source was found to be in a relatively bright state and a power-law fit to the differential photon spectrum yields a spectral index of 3.6 0.4{sub stat} 0.3{sub syst} with an integral flux above 200 GeV of (8.0 0.9{sub stat} 3.2{sub syst}) 10{sup 12} cm{sup 2} s{sup 1}. No short term variability could be detected during the bright state in 2011. Multi-wavelength data were obtained contemporaneously with the VERITAS observations in 2011 and cover optical (Super-LOTIS, MDM, Swift/UVOT), X-ray (Swift/XRT), and gamma-ray (Fermi-LAT) frequencies. These were used to construct the spectral energy distribution (SED) of B2 1215+30. A one-zone leptonic model is used to model the blazar emission and the results are compared to those of MAGIC from early 2011 and other VERITAS-detected blazars. The SED can be reproduced well with model parameters typical for VHE-detected BL Lac objects.

  15. Optical and ultraviolet observations of the narrow-lined type Ia SN 2012fr in NGC 1365

    SciTech Connect (OSTI)

    Zhang, Ju-Jia; Bai, Jin-Ming; Wang, Bo; Liu, Zheng-Wei [Yunnan Observatories (YNAO), Chinese Academy of Sciences, Kunming 650011 (China); Wang, Xiao-Feng; Zhao, Xu-Lin; Chen, Jun-Cheng [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Zhang, Tian-Meng, E-mail: jujia@ynao.ac.cn, E-mail: baijinming@ynao.ac.cn, E-mail: wang_xf@mail.tsinghua.edu.cn [National Astronomical Observatories of China (NAOC), Chinese Academy of Sciences, Beijing 100012 (China)

    2014-07-01

    Extensive optical and ultraviolet (UV) observations of the type Ia supernova (SN Ia) 2012fr are presented in this paper. It has a relatively high luminosity, with an absolute B-band peak magnitude of about 19.5 mag and a smaller post-maximum decline rate than normal SNe Ia (e.g., ?m {sub 15}(B) =0.85 0.05 mag). Based on the UV and optical light curves, we derived that a {sup 56}Ni mass of about 0.88 M {sub ?} was synthesized in the explosion. The earlier spectra are characterized by noticeable high-velocity features of Si II ?6355 and Ca II with velocities in the range of ?22, 000-25, 000 km s{sup 1}. At around the maximum light, these spectral features are dominated by the photospheric components which are noticeably narrower than normal SNe Ia. The post-maximum velocity of the photosphere remains almost constant at ?12,000 km s{sup 1} for about one month, reminiscent of the behavior of some luminous SNe Ia like SN 1991T. We propose that SN 2012fr may represent a subset of the SN 1991T-like SNe Ia viewed in a direction with a clumpy or shell-like structure of ejecta, in terms of a significant level of polarization reported in Maund et al. in 2013.

  16. FINAL REPORT: Reduction in Energy Consumption and Variability in Steel Foundry Operations

    SciTech Connect (OSTI)

    F. Peters

    2005-05-24

    This project worked to improve the efficiency of the steel casting industry by reducing the variability that occurs because of process and product variation. The project focused on the post shakeout operations since roughly half of the production costs are in this area. These improvements will reduce the amount of variability, making it easier to manage the operation and improve the competitiveness. The reduction in variability will also reduce the need for many rework operations, which will result in a direct reduction of energy usage, particularly by the reduction of repeated heat treatment operations. Further energy savings will be realized from the reduction of scrap and reduced handling. Field studies were conducted at ten steel foundries that represented the U.S. steel casting industry, for a total of over 100 weeks of production observation. These studies quantified the amount of variability, and looked toward determining the source. A focus of the data collected was the grinding operations since this is a major effort in the cleaning room, and it represents the overall casting quality. The grinding was divided into two categories, expected and unexpected. Expected grinding is that in which the location of the effort is known prior to making the casting, such as smoothing parting lines, gates, and riser contacts. Unexpected grinding, which was approximately 80% of the effort, was done to improve the surfaces at weld repair locations, to rectify burnt on sand, and other surface anomalies at random locations. Unexpected grinding represents about 80% of the grinding effort. By quantifying this effort, the project raised awareness within the industry and the industry is continuing to make improvements. The field studies showed that the amount of variation of grinding operations (normalized because of the diverse set of parts studied) was very consistent across the industry. The field studies identified several specific sources that individually contributed to large process variation. This indicates the need for ongoing monitoring of the process and system to quantify the effort being expended. A system to measure the grinding effort was investigated but did not prove to be successful. A weld wire counting system was shown to be very successful in tracking casting quality by monitoring the quantity of weld wire being expended on a per casting basis. Further use of such systems is highly recommended. The field studies showed that the visual inspection process for the casting surface was a potentially large source of process variation. Measurement system analysis studies were conducted at three steel casting producers. The tests measured the consistency of the inspectors in identifying the same surface anomalies. The repeatability (variation of the same operator inspecting the same casting) was found to be relatively consistent across the companies at about 60-70%. However, this is still are very large amount of variation. Reproducibility (variation of different operators inspecting the same casting) was worse, ranging between 20 to 80% at the three locations. This large amount of variation shows that there is a great opportunity for improvement. Falsely identifying anomalies for reworking will cause increased expense and energy consumption. This is particularly true if a weld repair and repeated heat treatment is required. However, not identifying an anomaly could also result in future rework processing, a customer return, or scrap. To help alleviate this problem, casting surface comparator plates were developed and distributed to the industry. These plates are very inexpensive which enables them to be provided to all those involved with casting surface quality, such as operators, inspectors, sales, and management.

  17. Collaborative project. Ocean-atmosphere interaction from meso- to planetary-scale. Mechanics, parameterization, and variability

    SciTech Connect (OSTI)

    Saravanan, Ramalingam; Small, Justin

    2015-12-01

    Most climate models are currently run with grid spacings of around 100km, which, with today’s computing power, allows for long (up to 1000 year) simulations, or ensembles of simulations to explore climate change and variability. However this grid spacing does not resolve important components of the weather/climate system such as atmospheric fronts and mesoscale systems, and ocean boundary currents and eddies. The overall aim of this project has been to look at the effect of these small-scale features on the weather/climate system using a suite of high and low resolution climate models, idealized models and observations. High-resolution global coupled integrations using CAM/CESM were carried out at NCAR by the lead PI. At TAMU, we have complemented the work at NCAR by analyzing datasets from the high-resolution (28km) CESM integrations (Small et al., 2014) as well as very high resolution (9km, 3km) runs using a coupled regional climate (CRCM) carried out locally. The main tasks carried out were: 1. Analysis of surface wind in observations and high-resolution CAM/CCSM simulations 2. Development of a feature-tracking algorithm for studying midlatitude air-sea interaction by following oceanic mesoscale eddies and creating composites of the atmospheric response overlying the eddies. 3. Applying the Lagrangian analysis technique in the Gulf Stream region to compare data from observational reanalyses, global CESM coupled simulations, 9km regional coupled simulations and 3km convection-resolving regional coupled simulations. Our main findings are that oceanic mesoscale eddies influence not just the atmospheric boundary layer above them, but also the lower portions of the free troposphere above the boundary layer. Such a vertical response could have implications for a remote influence of Gulf Stream oceanic eddies on North Atlantic weather patterns through modulation of the storm track, similar to what has been noted in the North Pacific. The coarse resolution observational reanalyses perhaps underestimate the atmospheric response, but the 28km global model resolution appears to be adequate to capture some, but not all, aspects of the boundary response. The higher resolution regional models show a stronger response in certain fields such as the latent heat flux.

  18. High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    SciTech Connect (OSTI)

    Tarau, Calin; Walker, Kara L.; Anderson, William G.

    2009-03-16

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling converter provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling engine. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 deg. C while the heat losses caused by the addition of the VCHP are 1.8 W.

  19. Luminous blue variables and superluminous supernovae from binary mergers

    SciTech Connect (OSTI)

    Justham, Stephen; Podsiadlowski, Philipp; Vink, Jorick S. E-mail: podsi@astro.ox.ac.uk

    2014-12-01

    Evidence suggests that the direct progenitor stars of some core-collapse supernovae (CCSNe) are luminous blue variables (LBVs), perhaps including some Type II 'superluminous supernovae' (SLSNe). We examine models in which massive stars gain mass soon after the end of core hydrogen burning. These are mainly intended to represent mergers following a brief contact phase during early Case B mass transfer, but may also represent stars which gain mass in the Hertzsprung Gap or extremely late during the main-sequence phase for other reasons. The post-accretion stars spend their core helium-burning phase as blue supergiants (BSGs), and many examples are consistent with being LBVs at the time of core collapse. Other examples are yellow supergiants at explosion. We also investigate whether such post-accretion stars may explode successfully after core collapse. The final core properties of post-accretion models are broadly similar to those of single stars with the same initial mass as the pre-merger primary star. More surprisingly, when early Case B accretion does affect the final core properties, the effect appears likely to favor a successful SN explosion, i.e., to make the core properties more like those of a lower-mass single star. However, the detailed structures of these cores sometimes display qualitative differences to any single-star model we have calculated. The rate of appropriate binary mergers may match the rate of SNe with immediate LBV progenitors; for moderately optimistic assumptions we estimate that the progenitor birthrate is ?1% of the CCSN rate.

  20. Observational Constraints on the Nature of the Dark Energy: First...

    Office of Scientific and Technical Information (OSTI)

    Observational Constraints on the Nature of the Dark Energy: First Cosmological Results From the ESSENCE Supernova Survey Citation Details In-Document Search Title: Observational...

  1. ARM - Field Campaign - The ARM Pilot Radiation Observation Experiment...

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

    from Observations in the ARM Pilot Radiation Observation Experiment Campaign Data Sets IOP Participant Data Source Description Final Data Tooman WSI Order Data Westwater ftirraob...

  2. Observation of Large Photoacoustic Signal Phase Changes During...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Observation of Large Photoacoustic Signal Phase Changes During a Diffusion Process Citation Details In-Document Search Title: Observation of Large Photoacoustic...

  3. Aided by Simulations, Scientists Observe Atomic Collapse State

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

    Collapse State Observed Aided by Simulations, Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013...

  4. Observation of a Macroscopically Quantum-Entangled Insulator

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

    Observation of a Macroscopically Quantum-Entangled Insulator Observation of a Macroscopically Quantum-Entangled Insulator Print Wednesday, 27 May 2009 00:00 It has recently been...

  5. Net Zero Waste - Tools and Technical Support ...and other observations...

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

    Net Zero Waste - Tools and Technical Support ...and other observations Net Zero Waste - Tools and Technical Support ...and other observations Presentation at Waste-to-Energy using...

  6. USGS-Earth Resources Observation and Science (EROS) Center |...

    Open Energy Info (EERE)

    USGS-Earth Resources Observation and Science (EROS) Center Jump to: navigation, search Tool Summary LAUNCH TOOL Name: USGS-Earth Resources Observation and Science (EROS) Center...

  7. Common Cyber Security Vulnerabilities Observed in Control System...

    Energy Savers [EERE]

    Common Cyber Security Vulnerabilities Observed in Control System Assessments by the INL NSTB Program Common Cyber Security Vulnerabilities Observed in Control System Assessments by...

  8. Observation of Ordered Structures in Counterion Layers near Wet...

    Office of Scientific and Technical Information (OSTI)

    Observation of Ordered Structures in Counterion Layers near Wet Charged Surfaces: A Potential Mechanism for Charge Inversion Citation Details In-Document Search Title: Observation ...

  9. ARM - Field Campaign - Arctic Lower Troposphere Observed Structure...

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

    govCampaignsArctic Lower Troposphere Observed Structure (ALTOS) Campaign Links Science Plan ALTOS Website Related Campaigns Supplement to Arctic Lower Troposphere Observed...

  10. High-resolution observations of the shock wave behavior for sunspot oscillations with the interface region imaging spectrograph

    SciTech Connect (OSTI)

    Tian, H.; DeLuca, E.; Reeves, K. K.; McKillop, S.; Golub, L.; Saar, S.; Testa, P.; Weber, M.; De Pontieu, B.; Martínez-Sykora, J.; Kleint, L.; Cheung, M.; Lemen, J.; Title, A.; Boerner, P.; Hurlburt, N.; Tarbell, T. D.; Wuelser, J. P.; Carlsson, M.; Hansteen, V.; and others

    2014-05-10

    We present the first results of sunspot oscillations from observations by the Interface Region Imaging Spectrograph. The strongly nonlinear oscillation is identified in both the slit-jaw images and the spectra of several emission lines formed in the transition region and chromosphere. We first apply a single Gaussian fit to the profiles of the Mg II 2796.35 Å, C II 1335.71 Å, and Si IV 1393.76 Å lines in the sunspot. The intensity change is ∼30%. The Doppler shift oscillation reveals a sawtooth pattern with an amplitude of ∼10 km s{sup –1} in Si IV. The Si IV oscillation lags those of C II and Mg II by ∼6 and ∼25 s, respectively. The line width suddenly increases as the Doppler shift changes from redshift to blueshift. However, we demonstrate that this increase is caused by the superposition of two emission components. We then perform detailed analysis of the line profiles at a few selected locations on the slit. The temporal evolution of the line core is dominated by the following behavior: a rapid excursion to the blue side, accompanied by an intensity increase, followed by a linear decrease of the velocity to the red side. The maximum intensity slightly lags the maximum blueshift in Si IV, whereas the intensity enhancement slightly precedes the maximum blueshift in Mg II. We find a positive correlation between the maximum velocity and deceleration, a result that is consistent with numerical simulations of upward propagating magnetoacoustic shock waves.

  11. Quantitative Imaging and In Situ Concentration Measurements of Quantum Dot Nanomaterials in Variably Saturated Porous Media

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Uyuşur, Burcu; Snee, Preston T.; Li, Chunyan; Darnault, Christophe J. G.

    2016-01-01

    Knowledge of the fate and transport of nanoparticles in the subsurface environment is limited, as techniques to monitor and visualize the transport and distribution of nanoparticles in porous media and measure their in situ concentrations are lacking. To address these issues, we have developed a light transmission and fluorescence method to visualize and measure in situ concentrations of quantum dot (QD) nanoparticles in variably saturated environments. Calibration cells filled with sand as porous medium and various known water saturation levels and QD concentrations were prepared. By measuring the intensity of the light transmitted through porous media exposed to fluorescent lightmore » and by measuring the hue of the light emitted by the QDs under UV light exposure, we obtained simultaneously in situ measurements of water saturation and QD nanoparticle concentrations with high spatial and temporal resolutions. Water saturation was directly proportional to the light intensity. A linear relationship was observed between hue-intensity ratio values and QD concentrations for constant water saturation levels. The advantages and limitations of the light transmission and fluorescence method as well as its implications for visualizing and measuring in situ concentrations of QDs nanoparticles in the subsurface environment are discussed.« less

  12. Accounting for sub-pixel variability of clouds and/or unresolved spectral variability, as needed, with generalized radiative transfer theory

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Davis, Anthony B.; Xu, Feng; Collins, William D.

    2015-03-01

    Atmospheric hyperspectral VNIR sensing struggles with sub-pixel variability of clouds and limited spectral resolution mixing molecular lines. Our generalized radiative transfer model addresses both issues with new propagation kernels characterized by power-law decay in space.

  13. A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low

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

    Temperature Combustion | Department of Energy A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored by the U.S. DOE's EERE FreedomCar and Fuel Partnership and 21st Century Truck Programs. PDF icon 2006_deer_hou.pdf More Documents & Publications Adaptive PCCI with Variable Orifice

  14. Monte-Carlo particle dynamics in a variable specific impulse magnetoplasma

    Office of Scientific and Technical Information (OSTI)

    rocket (Journal Article) | SciTech Connect Monte-Carlo particle dynamics in a variable specific impulse magnetoplasma rocket Citation Details In-Document Search Title: Monte-Carlo particle dynamics in a variable specific impulse magnetoplasma rocket The self-consistent mathematical model in a Variable Specific Impulse Magnetoplasma Rocket (VASIMR) is examined. Of particular importance is the effect of a magnetic nozzle in enhancing the axial momentum of the exhaust. Also, different

  15. A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus

    SciTech Connect (OSTI)

    Raustad, Richard A.

    2013-01-01

    This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.

  16. Production-Intent Lost-Motion Variable Valve Actuation Systems | Department

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

    of Energy Production-Intent Lost-Motion Variable Valve Actuation Systems Production-Intent Lost-Motion Variable Valve Actuation Systems Variable valve actuation with on/off IEGR pre-bump is an enabling technology for HCCI, PCCI, LTC and other advanced combustion techniques, and designs for production-intent equipment have been developed PDF icon deer09_ernest.pdf More Documents & Publications Expanding Robust HCCI Operation (Delphi CRADA) Rapid Compression Machine … A Key Experimental

  17. Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in

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

    Gasoline Powertrains | Department of Energy Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Presents two-stage variable compression ratio mechanism realized by varying the connecting rod length, description of the system layout, working principle and expected fuel savings benefits when used in current and future gasoline engine concepts PDF icon

  18. Six- and three-hourly meteorological observations from 223 USSR stations

    SciTech Connect (OSTI)

    Razuvaev, V.N.; Apasova, E.B.; Martuganov, R.A.; Kaiser, D.P.

    1995-04-01

    This document describes a database containing 6- and 3-hourly meteorological observations from a 223-station network of the former Soviet Union. These data have been made available through cooperation between the two principal climate data centers of the United States and Russia: the National Climatic Data Center (NCDC), in Asheville, North Carolina, and the All-Russian Research Institute of Hydrometeorological Information -- World Data Centre (RIHMI-WDC) in Obninsk. Station records consist of 6- and 3-hourly observations of some 24 meteorological variables including temperature, weather type, precipitation amount, cloud amount and type, sea level pressure, relative humidity, and wind direction and speed. The 6-hourly observations extend from 1936 to 1965; the 3-hourly observations extend from 1966 through the mid-1980s (1983, 1984, 1985, or 1986; depending on the station). These data have undergone extensive quality assurance checks by RIHMI-WDC, NCDC, and the Carbon Dioxide Information Analysis Center (CDIAC). The database represents a wealth of meteorological information for a large and climatologically important portion of the earth`s land area, and should prove extremely useful for a wide variety of regional climate change studies. These data are available free of charge as a numeric data package (NDP) from CDIAC. The NDP consists of this document and 40 data files that are available via the Internet or on 8mm tape. The total size of the database is {approximately}2.6 gigabytes.

  19. TAKING ADVANTAGE OF THE COS TIME-TAG CAPABILITY: OBSERVATIONS OF PULSATING HOT DQ WHITE DWARFS AND DISCOVERY OF A NEW ONE

    SciTech Connect (OSTI)

    Dufour, P.; Fontaine, G.; Bergeron, P. [Departement de Physique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, QC H3C 3J7 (Canada); Beland, S. [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309 (United States); Chayer, P., E-mail: dufourpa@astro.umontreal.ca, E-mail: fontaine@astro.umontreal.ca, E-mail: bergeron@astro.umontreal.ca, E-mail: sbeland@colorado.edu, E-mail: chayer@stsci.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2011-06-01

    We present an analysis of the ultraviolet light curves of five Hot DQ white dwarfs recently observed with the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope (HST). These light curves were constructed by extracting the time-tag information from the FUV and NUV spectroscopic data. Single-color light curves were thus produced in 60 s time bins. The Fourier analysis of these data successfully recovers the main pulsation modes of the three stars previously known to be variable from ground-based observations. We also report the discovery of pulsations in another object, SDSS J1153+0056, making it only the fifth member of the new class of variable Hot DQ stars and the first pulsating white dwarf to be discovered from space-based observations. The relatively high amplitudes of the modes observed in the FUV (2-4 times that observed in the optical) as well as the high fraction of stars variable in our sample suggest that most, if not all, Hot DQ white dwarfs might be pulsating at some level when observed at high enough sensitivity. Our results also underline the vast potential of the time-tag capability of the HST/COS combination.

  20. Variability of Load and Net Load in Case of Large Scale Distributed Wind Power

    SciTech Connect (OSTI)

    Holttinen, H.; Kiviluoma, J.; Estanqueiro, A.; Gomez-Lazaro, E.; Rawn, B.; Dobschinski, J.; Meibom, P.; Lannoye, E.; Aigner, T.; Wan, Y. H.; Milligan, M.

    2011-01-01

    Large scale wind power production and its variability is one of the major inputs to wind integration studies. This paper analyses measured data from large scale wind power production. Comparisons of variability are made across several variables: time scale (10-60 minute ramp rates), number of wind farms, and simulated vs. modeled data. Ramp rates for Wind power production, Load (total system load) and Net load (load minus wind power production) demonstrate how wind power increases the net load variability. Wind power will also change the timing of daily ramps.

  1. May 2013 PSERC Webinar: Managing Wind Variability with Self-Reserves...

    Energy Savers [EERE]

    The DOE-funded Power Systems Engineering Research Center (PSERC) is offering a free public webinar on managing wind variability in energy production. The webinar will be held ...

  2. Session 3: Impact on U.S. Ancillary Services Markets from Variable Renewable Energy (Presentation)

    SciTech Connect (OSTI)

    Cochran, J.

    2013-05-01

    The presentation provides an overview of how increasing penetrations of variable renewable energy on the electricity grid are impacting ancillary services markets in the United States.

  3. Market Characteristics for Efficient Integration of Variable Generation in the Western Interconnection

    SciTech Connect (OSTI)

    Milligan, M.; Kirby, B.

    2010-08-01

    The overriding purpose of this report is to establish the physical requirements of a power system that can accommodate high levels of variable generation.

  4. Future projection of mean and variability of the Asian Summer Monsoon and Indian Ocean Climate systems

    SciTech Connect (OSTI)

    Annamalai, H

    2014-09-15

    The overall goal of this project is to assess the ability of the CMIP3/5 models to simulate the Indian-Ocean monsoon systems. The PI along with post-docs investigated research issues ranging from synoptic systems to long-term trends over the Asian monsoon region. The PI applied diagnostic tools such as moist static energy (MSE) to isolate: the moist and radiative processes responsible for extended monsoon breaks over South Asia, precursors in the ENSO-monsoon association, reasons for the drying tendency over South Asia and the possible effect on tropical Indian Ocean climate anomalies influencing certain aspects of ENSO characteristics. By diagnosing various observations and coupled model simulations, we developed working hypothesis and tested them by carrying out sensitivity experiments with both linear and nonlinear models. Possible physical and dynamical reasons for model sensitivities were deduced. On the teleconnection front, the ability of CMIP5 models in representing the monsoon-desert mechanism was examined recently. Further more, we have applied a suite of diagnostics and have performed an in depth analysis on CMIP5 integrations to isolate the possible reasons for the ENSO-monsoon linkage or lack thereof. The PI has collaborated with Dr. K.R. Sperber of PCMDI and other CLIVAR Asian-Australian monsoon panel members in understanding the ability of CMIP3/5 models in capturing monsoon and its spectrum of variability. The objective and process-based diagnostics aided in selecting models that best represent the present-day monsoon and its variability that are then employed for future projections. Two major highlights were an invitation to write a review on present understanding monsoons in a changing climate in Nature Climate Change, and identification of an east-west shift in observed monsoon rainfall (more rainfall over tropical western Pacific and drying tendency over South Asia) in the last six decades and attributing that shift to SST rise over the tropical western Pacific. On the training of post-doctoral scientists: the PI spent considerable amount of time and efforts in introducing the post-docs into climate modeling and designing the numerical experiments. With training provided and knowledge gained, post-docs worked in the project obtained long term positions elsewhere. The PI also enjoyed the experience in managing the works and educating work ethics to the younger generation. Based on the research achievements and publications, the PI gave invited talks in major international monsoon conferences/workshops, and gave lectures in various research organizations in the last six years. Finally, during the project period, the PI attended all the DOE organized PIs meeting and presented the major results. Some of the major implications of the project include: (i) Sustained observational efforts are necessary to monitor the three-dimensional moisture distribution over the Asian monsoon region that would aid in better understanding, modeling and predicting severe monsoons well in advance and (ii) process-based diagnostics lead pathways for model improvements.

  5. ATMOSPHERIC CIRCULATION OF BROWN DWARFS: JETS, VORTICES, AND TIME VARIABILITY

    SciTech Connect (OSTI)

    Zhang, Xi; Showman, Adam P.

    2014-06-10

    A variety of observational evidence demonstrates that brown dwarfs exhibit active atmospheric circulations. In this study we use a shallow-water model to investigate the global atmospheric dynamics in the stratified layer overlying the convective zone on these rapidly rotating objects. We show that the existence and properties of the atmospheric circulation crucially depend on key parameters including the energy injection rate and radiative timescale. Under conditions of strong internal heat flux and weak radiative dissipation, a banded flow pattern comprised of east-west jet streams spontaneously emerges from the interaction of atmospheric turbulence with the planetary rotation. In contrast, when the internal heat flux is weak and/or radiative dissipation is strong, turbulence injected into the atmosphere damps before it can self-organize into jets, leading to a flow dominated by transient eddies and isotropic turbulence instead. The simulation results are not very sensitive to the form of the forcing. Based on the location of the transition between jet-dominated and eddy-dominated regimes, we suggest that many brown dwarfs may exhibit atmospheric circulations dominated by eddies and turbulence (rather than jets) due to the strong radiative damping on these worlds, but a jet structure is also possible under some realistic conditions. Our simulated light curves capture important features from observed infrared light curves of brown dwarfs, including amplitude variations of a few percent and shapes that fluctuate between single-peak and multi-peak structures. More broadly, our work shows that the shallow-water system provides a useful tool to illuminate fundamental aspects of the dynamics on these worlds.

  6. Development and Performance of Detectors for the Cryogenic Dark Matter Search Experiment with an Increased Sensitivity Based on a Maximum Likelihood Analysis of Beta Contamination

    SciTech Connect (OSTI)

    Driscoll, Donald D.; /Case Western Reserve U.

    2004-01-01

    The Cryogenic Dark Matter Search (CDMS) uses cryogenically-cooled detectors made of germanium and silicon in an attempt to detect dark matter in the form of Weakly-Interacting Massive Particles (WIMPs). The expected interaction rate of these particles is on the order of 1/kg/day, far below the 200/kg/day expected rate of background interactions after passive shielding and an active cosmic ray muon veto. Our detectors are instrumented to make a simultaneous measurement of both the ionization energy and thermal energy deposited by the interaction of a particle with the crystal substrate. A comparison of these two quantities allows for the rejection of a background of electromagnetically-interacting particles at a level of better than 99.9%. The dominant remaining background at a depth of {approx} 11 m below the surface comes from fast neutrons produced by cosmic ray muons interacting in the rock surrounding the experiment. Contamination of our detectors by a beta emitter can add an unknown source of unrejected background. In the energy range of interest for a WIMP study, electrons will have a short penetration depth and preferentially interact near the surface. Some of the ionization signal can be lost to the charge contacts there and a decreased ionization signal relative to the thermal signal will cause a background event which interacts at the surface to be misidentified as a signal event. We can use information about the shape of the thermal signal pulse to discriminate against these surface events. Using a subset of our calibration set which contains a large fraction of electron events, we can characterize the expected behavior of surface events and construct a cut to remove them from our candidate signal events. This thesis describes the development of the 6 detectors (4 x 250 g Ge and 2 x 100 g Si) used in the 2001-2002 CDMS data run at the Stanford Underground Facility with a total of 119 livedays of data. The preliminary results presented are based on the first use of a beta-eliminating cut based on a maximum-likelihood characterization described above.

  7. DIAGNOSTICS OF AGN-DRIVEN MOLECULAR OUTFLOWS IN ULIRGs FROM HERSCHEL-PACS OBSERVATIONS OF OH AT 119 ?m

    SciTech Connect (OSTI)

    Spoon, H. W. W.; Lebouteiller, V.; Farrah, D.; Gonzlez-Alfonso, E.; Bernard-Salas, J.; Urrutia, T.; Rigopoulou, D.; Verma, A.; Westmoquette, M. S.; Smith, H. A.; Afonso, J.; Pearson, C.; Cormier, D.; Efstathiou, A.; Borys, C.; Etxaluze, M.; Clements, D. L.

    2013-10-01

    We report on our observations of the 79 and 119 ?m doublet transitions of OH for 24 local (z < 0.262) ULIRGs observed with Herschel-PACS as part of the Herschel ULIRG Survey (HERUS). Some OH 119 ?m profiles display a clear P-Cygni shape and therefore imply outflowing OH gas, while other profiles are predominantly in absorption or are completely in emission. We find that the relative strength of the OH emission component decreases as the silicate absorption increases. This result locates the OH outflows inside the obscured nuclei. The maximum outflow velocities for our sources range from less than 100 to ?2000 km s{sup 1}, with 15/24 (10/24) sources showing OH absorption at velocities exceeding 700 km s{sup 1} (1000 km s{sup 1}). Three sources show maximum OH outflow velocities exceeding that of Mrk231. Since outflow velocities above 500-700 km s{sup 1} are thought to require an active galactic nucleus (AGN) to drive them, about two-thirds of our ULIRG sample may host AGN-driven molecular outflows. This finding is supported by the correlation we find between the maximum OH outflow velocity and the IR-derived bolometric AGN luminosity. No such correlation is found with the IR-derived star formation rate. The highest outflow velocities are found among sources that are still deeply embedded. We speculate that the molecular outflows in these sources may be in an early phase of disrupting the nuclear dust veil before these sources evolve into less-obscured AGNs. Four of our sources show high-velocity wings in their [C II] fine-structure line profiles, implying neutral gas outflow masses of at least (2-4.5) 10{sup 8} M{sub ?}.

  8. Implications of Wide-Area Geographic Diversity for Short- Term Variability of Solar Power

    SciTech Connect (OSTI)

    Mills, Andrew; Wiser, Ryan

    2010-08-23

    Worldwide interest in the deployment of photovoltaic generation (PV) is rapidly increasing. Operating experience with large PV plants, however, demonstrates that large, rapid changes in the output of PV plants are possible. Early studies of PV grid impacts suggested that short-term variability could be a potential limiting factor in deploying PV. Many of these early studies, however, lacked high-quality data from multiple sites to assess the costs and impacts of increasing PV penetration. As is well known for wind, accounting for the potential for geographic diversity can significantly reduce the magnitude of extreme changes in aggregated PV output, the resources required to accommodate that variability, and the potential costs of managing variability. We use measured 1-min solar insolation for 23 time-synchronized sites in the Southern Great Plains network of the Atmospheric Radiation Measurement program and wind speed data from 10 sites in the same network to characterize the variability of PV with different degrees of geographic diversity and to compare the variability of PV to the variability of similarly sited wind. The relative aggregate variability of PV plants sited in a dense 10 x 10 array with 20 km spacing is six times less than the variability of a single site for variability on time scales less than 15-min. We find in our analysis of wind and PV plants similarly sited in a 5 x 5 grid with 50 km spacing that the variability of PV is only slightly more than the variability of wind on time scales of 5-15 min. Over shorter and longer time scales the level of variability is nearly identical. Finally, we use a simple approximation method to estimate the cost of carrying additional reserves to manage sub-hourly variability. We conclude that the costs of managing the short-term variability of PV are dramatically reduced by geographic diversity and are not substantially different from the costs for managing the short-term variability of similarly sited wind in this region.

  9. Spatially resolved and observer-free experimental quantification of spatial resolution in tomographic images

    SciTech Connect (OSTI)

    Tsekenis, S. A.; McCann, H.; Tait, N.

    2015-03-15

    We present a novel framework and experimental method for the quantification of spatial resolution of a tomography system. The framework adopts the black box view of an imaging system, considering only its input and output. The tomography system is locally stimulated with a step input, viz., a sharp edge. The output, viz., the reconstructed images, is analysed by Fourier decomposition of their spatial frequency components, and the local limiting spatial resolution is determined using a cut-off threshold. At no point is an observer involved in the process. The framework also includes a means of translating the quantification region in the imaging space, thus creating a spatially resolved map of objectively quantified spatial resolution. As a case-study, the framework is experimentally applied using a gaseous propane phantom measured by a well-established chemical species tomography system. A spatial resolution map consisting of 28 regions is produced. In isolated regions, the indicated performance is 4-times better than that suggested in the literature and varies by 57% across the imaging space. A mechanism based on adjacent but non-interacting beams is hypothesised to explain the observed behaviour. The mechanism suggests that, as also independently concluded by other methods, a geometrically regular beam array maintains maximum objectivity in reconstructions. We believe that the proposed framework, methodology, and findings will be of value in the design and performance evaluation of tomographic imaging arrays and systems.

  10. SDO/AIA OBSERVATIONS OF LARGE-AMPLITUDE LONGITUDINAL OSCILLATIONS IN A SOLAR FILAMENT

    SciTech Connect (OSTI)

    Li Ting; Zhang Jun E-mail: zjun@nao.cas.cn

    2012-11-20

    We present the first Solar Dynamics Observatory/Atmospheric Imaging Assembly observations of the large-amplitude longitudinal (LAL) oscillations in the south and north parts (SP and NP) of a solar filament on 2012 April 7. Both oscillations are triggered by flare activities close to the filament. The period varies with filamentary threads, ranging from 44 to 67 minutes. The oscillations of different threads are out of phase, and their velocity amplitudes vary from 30 to 60 km s{sup -1}, with a maximum displacement of about 25 Mm. The oscillations of the SP repeat for about four cycles without any significant damping and then a nearby C2.4 flare causes the transition from the LAL oscillations of the filament to its later eruption. The filament eruption is also associated with a coronal mass ejection and a B6.8 flare. However, the oscillations of the NP damp with time and die out at last. Our observations show that the activated part of the SP repeatedly shows a helical motion. This indicates that the magnetic structure of the filament is possibly modified during this process. We suggest that the restoring force is the coupling of the magnetic tension and gravity.

  11. The solar wind neon abundance observed with ACE/SWICS and ULYSSES/SWICS

    SciTech Connect (OSTI)

    Shearer, Paul; Raines, Jim M.; Lepri, Susan T.; Thomas, Jonathan W.; Gilbert, Jason A.; Landi, Enrico; Zurbuchen, Thomas H.; Von Steiger, Rudolf

    2014-07-01

    Using in situ ion spectrometry data from ACE/SWICS, we determine the solar wind Ne/O elemental abundance ratio and examine its dependence on wind speed and evolution with the solar cycle. We find that Ne/O is inversely correlated with wind speed, is nearly constant in the fast wind, and correlates strongly with solar activity in the slow wind. In fast wind streams with speeds above 600 km s{sup 1}, we find Ne/O = 0.10 0.02, in good agreement with the extensive polar observations by Ulysses/SWICS. In slow wind streams with speeds below 400 km s{sup 1}, Ne/O ranges from a low of 0.12 0.02 at solar maximum to a high of 0.17 0.03 at solar minimum. These measurements place new and significant empirical constraints on the fractionation mechanisms governing solar wind composition and have implications for the coronal and photospheric abundances of neon and oxygen. The results are made possible by a new data analysis method that robustly identifies rare elements in the measured ion spectra. The method is also applied to Ulysses/SWICS data, which confirms the ACE observations and extends our view of solar wind neon into the three-dimensional heliosphere.

  12. Optical observations of the type Ic supernova 2007gr in NGC 1058

    SciTech Connect (OSTI)

    Chen, Juncheng; Wang, Xiaofeng; Li, Junzheng [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Ganeshalingam, Mohan; Silverman, Jeffrey M.; Filippenko, Alexei V.; Li, Weidong; Chornock, Ryan; Steele, Thea, E-mail: cjc09@mails.tsinghua.edu.cn, E-mail: wang_xf@mail.tsinghua.edu.cn [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

    2014-08-01

    We present extensive optical observations of the normal Type Ic supernova (SN) 2007gr, spanning from about one week before maximum light to more than one year thereafter. The optical light and color curves of SN 2007gr are very similar to those of the broad-lined Type Ic SN 2002ap, but the spectra show remarkable differences. The optical spectra of SN 2007gr are characterized by unusually narrow lines, prominent carbon lines, and slow evolution of the line velocity after maximum light. The earliest spectrum (taken at t = 8 days) shows a possible signature of helium (He I ?5876 at a velocity of ?19,000 km s{sup 1}). Moreover, the larger intensity ratio of the [O I] ?6300 and ?6364 lines inferred from the early nebular spectra implies a lower opacity of the ejecta shortly after the explosion. These results indicate that SN 2007gr perhaps underwent a less energetic explosion of a smaller-mass Wolf-Rayet star (?8-9 M{sub ?}) in a binary system, as favored by an analysis of the progenitor environment through pre-explosion and post-explosion Hubble Space Telescope images. In the nebular spectra, asymmetric double-peaked profiles can be seen in the [O I] ?6300 and Mg I] ?4571 lines. We suggest that the two peaks are contributed by the blueshifted and rest-frame components. The similarity in velocity structure and the different evolution of the strength of the two components favor an aspherical explosion with the ejecta distributed in a torus or disk-like geometry, but inside the ejecta the O and Mg have different distributions.

  13. Far infrared supplement: Catalog of infrared observations, second edition

    SciTech Connect (OSTI)

    Gezari, D.Y.; Schmitz, M.; Mead, J.M.

    1988-08-01

    The Far Infrared Supplement: Catalog of Infrared Observations summarizes all infrared astronomical observations at far infrared wavelengths (5 to 1000 microns) published in the scientific literature from 1965 through 1986. The Supplement list contain 25 percent of the observations in the full Catalog of Infrared Observations (CIO), and essentially eliminates most visible stars from the listings. The Supplement is thus more compact than the main catalog, and is intended for easy reference during astronomical observations. The Far Infrared Supplement (2nd Edition) includes the Index of Infrared Source Positions and the Bibliography of Infrared Astronomy for the subset of far infrared observations listed.

  14. Statistical characteristics of cloud variability. Part 2: Implication for parameterizations of microphysical and radiative transfer processes in climate models

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Huang, Dong; Liu, Yangang

    2014-09-27

    The effects of subgrid cloud variability on grid-average microphysical rates and radiative fluxes are examined by use of long-term retrieval products at the Tropical West Pacific, Southern Great Plains, and North Slope of Alaska sites of the Department of Energy's Atmospheric Radiation Measurement program. Four commonly used distribution functions, the truncated Gaussian, Gamma, lognormal, and Weibull distributions, are constrained to have the same mean and standard deviation as observed cloud liquid water content. The probability density functions are then used to upscale relevant physical processes to obtain grid-average process rates. It is found that the truncated Gaussian representation results inmoreup to 30% mean bias in autoconversion rate, whereas the mean bias for the lognormal representation is about 10%. The Gamma and Weibull distribution function performs the best for the grid-average autoconversion rate with the mean relative bias less than 5%. For radiative fluxes, the lognormal and truncated Gaussian representations perform better than the Gamma and Weibull representations. The results show that the optimal choice of subgrid cloud distribution function depends on the nonlinearity of the process of interest, and thus, there is no single distribution function that works best for all parameterizations. Examination of the scale (window size) dependence of the mean bias indicates that the bias in grid-average process rates monotonically increases with increasing window sizes, suggesting the increasing importance of subgrid variability with increasing grid sizes.less

  15. Searches for supersymmetry using the MT2 variable in hadronic events produced in pp collisions at 8 TeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Khachatryan, V.

    2015-05-15

    Searches for supersymmetry (SUSY) are performed using a sample of hadronic events produced in 8 TeV pp collisions at the CERN LHC. The searches are based on the MT2 variable, which is a measure of the transverse momentum imbalance in an event. The data were collected with the CMS detector and correspond to an integrated luminosity of 19.5 fb?. Two related searches are performed. The first is an inclusive search based on signal regions defined by the value of the MT2 variable, the hadronic energy in the event, the jet multiplicity, and the number of jets identified as originating frommorebottom quarks. The second is a search for a mass peak corresponding to a Higgs boson decaying to a bottom quark-antiquark pair, where the Higgs boson is produced as a decay product of a SUSY particle. For both searches, the principal backgrounds are evaluated with data control samples. No significant excess over the expected number of background events is observed, and exclusion limits on various SUSY models are derived.less

  16. Collaborative project. Ocean-atmosphere interaction from meso-to planetary-scale. Mechanisms, parameterization, and variability

    SciTech Connect (OSTI)

    Small, Richard; Bryan, Frank; Tribbia, Joseph; Park, Sungsu; Dennis, John; Saravanan, R.; Schneider, Niklas; Kwon, Young-Oh

    2015-06-11

    This project aims to improve long term global climate simulations by resolving ocean mesoscale activity and the corresponding response in the atmosphere. The main computational objectives are; i) to perform and assess Community Earth System Model (CESM) simulations with the new Community Atmospheric Model (CAM) spectral element dynamical core; ii) use static mesh refinement to focus on oceanic fronts; iii) develop a new Earth System Modeling tool to investigate the atmospheric response to fronts by selectively filtering surface flux fields in the CESM coupler. The climate research objectives are 1) to improve the coupling of ocean fronts and the atmospheric boundary layer via investigations of dependency on model resolution and stability functions: 2) to understand and simulate the ensuing tropospheric response that has recently been documented in observations: and 3) to investigate the relationship of ocean frontal variability to low frequency climate variability and the accompanying storm tracks and extremes in high resolution simulations. This is a collaborative multi-institution project consisting of computational scientists, climate scientists and climate model developers. It specifically aims at DOE objectives of advancing simulation and predictive capability of climate models through improvements in resolution and physical process representation.

  17. Statistical characteristics of cloud variability. Part 2: Implication for parameterizations of microphysical and radiative transfer processes in climate models

    SciTech Connect (OSTI)

    Huang, Dong; Liu, Yangang

    2014-09-27

    The effects of subgrid cloud variability on grid-average microphysical rates and radiative fluxes are examined by use of long-term retrieval products at the Tropical West Pacific, Southern Great Plains, and North Slope of Alaska sites of the Department of Energy's Atmospheric Radiation Measurement program. Four commonly used distribution functions, the truncated Gaussian, Gamma, lognormal, and Weibull distributions, are constrained to have the same mean and standard deviation as observed cloud liquid water content. The probability density functions are then used to upscale relevant physical processes to obtain grid-average process rates. It is found that the truncated Gaussian representation results in up to 30% mean bias in autoconversion rate, whereas the mean bias for the lognormal representation is about 10%. The Gamma and Weibull distribution function performs the best for the grid-average autoconversion rate with the mean relative bias less than 5%. For radiative fluxes, the lognormal and truncated Gaussian representations perform better than the Gamma and Weibull representations. The results show that the optimal choice of subgrid cloud distribution function depends on the nonlinearity of the process of interest, and thus, there is no single distribution function that works best for all parameterizations. Examination of the scale (window size) dependence of the mean bias indicates that the bias in grid-average process rates monotonically increases with increasing window sizes, suggesting the increasing importance of subgrid variability with increasing grid sizes.

  18. Twisted MoSe2 bilayers with variable local stacking and interlayer coupling revealed by low-frequency Raman spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Puretzky, Alexander A.; Liang, Liangbo; Li, Xufan; Xiao, Kai; Sumpter, Bobby G.; Meunier, Vincent; Geohegan, David B.

    2016-01-14

    Unique twisted bilayers of MoSe2 with multiple stacking orientations and interlayer couplings in the narrow range of twist angles, 60 ± 3°, are revealed by low-frequency Raman spectroscopy and theoretical analysis. The slight deviation from 60 allows the concomitant presence of patches featuring all three high-symmetry stacking configurations (2H or AA', AB', A'B) in one unique bilayer system. In this case, the periodic arrangement of the patches and their size strongly depend on the twist angle. Ab initio modeling predicts significant changes in frequencies and intensities of low-frequency modes versus stacking and twist angle. Experimentally, the variable stacking and couplingmore » across the interface is revealed by the appearance of two breathing modes corresponding to the mixture of the high-symmetry stacking configurations and unaligned regions of monolayers. Only one breathing mode is observed outside the narrow range of twist angles. This indicates a stacking transition to unaligned monolayers with mismatched atom registry without the in-plane restoring force required to generate a shear mode. As a result, the variable interlayer coupling and spacing in transition metal dichalcogenide bilayers revealed in this study may provide a new platform for optoelectronic applications of these materials.« less

  19. Method and system to estimate variables in an integrated gasification combined cycle (IGCC) plant

    DOE Patents [OSTI]

    Kumar, Aditya; Shi, Ruijie; Dokucu, Mustafa

    2013-09-17

    System and method to estimate variables in an integrated gasification combined cycle (IGCC) plant are provided. The system includes a sensor suite to measure respective plant input and output variables. An extended Kalman filter (EKF) receives sensed plant input variables and includes a dynamic model to generate a plurality of plant state estimates and a covariance matrix for the state estimates. A preemptive-constraining processor is configured to preemptively constrain the state estimates and covariance matrix to be free of constraint violations. A measurement-correction processor may be configured to correct constrained state estimates and a constrained covariance matrix based on processing of sensed plant output variables. The measurement-correction processor is coupled to update the dynamic model with corrected state estimates and a corrected covariance matrix. The updated dynamic model may be configured to estimate values for at least one plant variable not originally sensed by the sensor suite.

  20. WEATHER ON THE NEAREST BROWN DWARFS: RESOLVED SIMULTANEOUS MULTI-WAVELENGTH VARIABILITY MONITORING OF WISE J104915.57531906.1AB

    SciTech Connect (OSTI)

    Biller, Beth A.; Crossfield, Ian J. M.; Mancini, Luigi; Ciceri, Simona; Kopytova, Taisiya G.; Bonnefoy, Mickal; Deacon, Niall R.; Schlieder, Joshua E.; Buenzli, Esther; Brandner, Wolfgang; Bailer-Jones, Coryn A. L.; Henning, Thomas; Goldman, Bertrand; Southworth, John; Allard, France; Homeier, Derek; Freytag, Bernd; Greiner, Jochen

    2013-11-20

    We present two epochs of MPG/ESO 2.2m GROND simultaneous six-band (r'i'z' JHK) photometric monitoring of the closest known L/T transition brown dwarf binary WISE J104915.57531906.1AB. We report here the first resolved variability monitoring of both the T0.5 and L7.5 components. We obtained 4 hr of focused observations on the night of 2013 April 22 (UT), as well as 4 hr of defocused (unresolved) observations on the night of 2013 April 16 (UT). We note a number of robust trends in our light curves. The r' and i' light curves appear to be anti-correlated with z' and H for the T0.5 component and in the unresolved light curve. In the defocused dataset, J appears correlated with z' and H and anti-correlated with r' and i', while in the focused dataset we measure no variability for J at the level of our photometric precision, likely due to evolving weather phenomena. In our focused T0.5 component light curve, the K band light curve displays a significant phase offset relative to both H and z'. We argue that the measured phase offsets are correlated with atmospheric pressure probed at each band, as estimated from one-dimensional atmospheric models. We also report low-amplitude variability in i' and z' intrinsic to the L7.5 component.