National Library of Energy BETA

Sample records for maximum variable observations

  1. Tropical climate variability from the last glacial maximum to the present

    E-Print Network [OSTI]

    Dahl, Kristina Ariel

    2005-01-01

    This thesis evaluates the nature and magnitude of tropical climate variability from the Last Glacial Maximum to the present. The temporal variability of two specific tropical climate phenomena is examined. The first is the ...

  2. 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.

  3. Variable Selection for Modeling the Absolute Magnitude at Maximum of Type Ia Supernovae

    E-Print Network [OSTI]

    Uemura, Makoto; Kawabata, S; Ikeda, Shiro; Maeda, Keiichi

    2015-01-01

    We discuss what is an appropriate set of explanatory variables in order to predict the absolute magnitude at the maximum of Type Ia supernovae. In order to have a good prediction, the error for future data, which is called the "generalization error," should be small. We use cross-validation in order to control the generalization error and LASSO-type estimator in order to choose the set of variables. This approach can be used even in the case that the number of samples is smaller than the number of candidate variables. We studied the Berkeley supernova database with our approach. Candidates of the explanatory variables include normalized spectral data, variables about lines, and previously proposed flux-ratios, as well as the color and light-curve widths. As a result, we confirmed the past understanding about Type Ia supernova: i) The absolute magnitude at maximum depends on the color and light-curve width. ii) The light-curve width depends on the strength of Si II. Recent studies have suggested to add more va...

  4. STRAY-LIGHT CORRECTION IN MAGNETOGRAPH OBSERVATIONS USING THE MAXIMUM ENTROPY METHOD

    E-Print Network [OSTI]

    STRAY-LIGHT CORRECTION IN MAGNETOGRAPH OBSERVATIONS USING THE MAXIMUM ENTROPY METHOD JONGCHUL CHAE1 June 1998; accepted 17 July 1998) Abstract. We have developed a method of stray-light correction which is applicable to filter-based magnetograph observations. Stray-light-corrected Stokes images are obtained

  5. Large deviations of the maximum of independent and identically distributed random variables

    E-Print Network [OSTI]

    Pierpaolo Vivo

    2015-07-20

    A pedagogical account of some aspects of Extreme Value Statistics (EVS) is presented from the somewhat non-standard viewpoint of Large Deviation Theory. We address the following problem: given a set of $N$ i.i.d. random variables $\\{X_1,\\ldots,X_N\\}$ drawn from a parent probability density function (pdf) $p(x)$, what is the probability that the maximum value of the set $X_{\\mathrm{max}}=\\max_i X_i$ is "atypically larger" than expected? The cases of exponential and Gaussian distributed variables are worked out in detail, and the right rate function for a general pdf in the Gumbel basin of attraction is derived. The Gaussian case convincingly demonstrates that the full rate function cannot be determined from the knowledge of the limiting distribution (Gumbel) alone, thus implying that it indeed carries additional information. Given the simplicity and richness of the result and its derivation, its absence from textbooks, tutorials and lecture notes on EVS for physicists appears inexplicable.

  6. 8) Stratospheric equatorial variability a) Observations

    E-Print Network [OSTI]

    Lott, Francois

    speed. Phase lines inclined eastward when altitude increases indicating upward propation Signal field) Westward phase propagation but eastward group propagation Phase lines inclined westward Signal;5 Satellites wind observations (UARS, Swinbak et Ortland 1997) The Quasi-Biennial Oscillation (low stratosphere

  7. Influence of the Eurasian snow cover on the Indian summer monsoon variability in observed climatologies and CMIP3

    E-Print Network [OSTI]

    Influence of the Eurasian snow cover on the Indian summer monsoon variability in observed of the winter/spring Eurasian snow cover on the subsequent Indian summer precipitation using sev- eral statistical tools including a maximum covariance analysis. The snow­monsoon relationship is explored using

  8. Influence of the Eurasian snow cover on the Indian summer monsoon variability in observed climatologies and CMIP3

    E-Print Network [OSTI]

    Influence of the Eurasian snow cover on the Indian summer monsoon variability in observed the possible influence of the winter/spring Eurasian snow cover on the subsequent Indian summer precipitation using sev- eral statistical tools including a maximum covariance analysis. The snow­monsoon relationship

  9. 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.

  10. Observed Variability of the Solar Mg II h Spectral Line

    E-Print Network [OSTI]

    Schmit, Donald; De Pontieu, Bart; McIntosh, Scott; Leenaarts, Jorrit; Carlsson, Mats

    2015-01-01

    The Mg II h&k doublet are two of the primary spectral lines observed by the Sun-pointing Interface Region Imaging Spectrograph (IRIS). These lines are tracers of the magnetic and thermal environment that spans from the photosphere to the upper chromosphere. We use a double gaussian model to fit the Mg II h profile for a full-Sun mosaic dataset taken 24-Aug-2014. We use the ensemble of high-quality profile fits to conduct a statistical study on the variability of the line profile as it relates the magnetic structure, dynamics, and center-to-limb viewing angle. The average internetwork profile contains a deeply reversed core and is weakly asymmetric at h2. In the internetwork, we find a strong correlation between h3 wavelength and profile asymmetry as well h1 width and h2 width. The average reversal depth of the h3 core is inversely related to the magnetic field. Plage and sunspots exhibit many profiles which do not contain a reversal. These profiles also occur infrequently in the internetwork. We see indic...

  11. 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.

  12. Observed climate variability and change of relevance to the biosphere

    E-Print Network [OSTI]

    Dai, Aiguo

    . Karl, and Kevin P. Gallo1 NOAA National Climatic Data Center, Asheville, North Carolina David AObserved climate variability and change of relevance to the biosphere David R. Easterling, Thomas R the current instrumental evidence regarding climate variations and change during the 20th century emphasizing

  13. Optimization of the transmission of observable expectation values and observable statistics in Continuous Variable Teleportation

    E-Print Network [OSTI]

    L. Albano Farias; J. Stephany

    2010-09-28

    We analyze the statistics of observables in continuous variable quantum teleportation in the formalism of the characteristic function. We derive expressions for average values of output state observables in particular cumulants which are additive in terms of the input state and the resource of teleportation. Working with Squeezed Bell-like states, which may be optimized in a free parameter for better teleportation performance we discuss the relation between resources optimal for fidelity and for different observable averages. We obtain the values of the free parameter which optimize the central momenta and cumulants up to fourth order. For the cumulants the distortion between in and out states due to teleportation depends only on the resource. We obtain optimal parameters for the second and fourth order cumulants which do not depend on the squeezing of the resource. The second order central momenta which is equal to the second order cumulants and the photon number average are optimized by the same resource. We show that the optimal fidelity resource, found in reference (Phys. Rev. A {\\bf 76}, 022301 (2007)) to depend also on the characteristics of input, tends for high squeezing to the resource which optimizes the second order momenta. A similar behavior is obtained for the resource which optimizes the photon statistics which is treated here using the sum of the squared differences in photon probabilities of input and output states as the distortion measure. This is interpreted to mean that the distortions associated to second order momenta dominates the behavior of the output state for large squeezing of the resource. Optimal fidelity and optimal photon statistics resources are compared and is shown that for mixtures of Fock states they are equivalent.

  14. Kepler observations of variability in B-type stars

    E-Print Network [OSTI]

    Balona, L A; De Cat, P; Handler, G; Gutierrez-Soto, J; Engelbrecht, C A; Frescura, F; Briquet, M; Cuypers, J; Daszynska-Daszkiewicz, J; Degroote, P; Dukes, R J; Garcia, R A; Green, E M; Heber, U; Kawaler, S D; Ostensen, R; Pricopi, D; Roxburgh, I; Salmon, S; Smith, M A; Suarez, J C; Suran, M; Szabo, R; Uytterhoeven, K; Christensen-Dalsgaard,; Kjeldsen, H; Caldwell, D A; Girouard, F R; Sanderfer, D T

    2011-01-01

    The analysis of the light curves of 48 B-type stars observed by Kepler is presented. Among these are 15 pulsating stars, all of which show low frequencies characteristic of SPB stars. Seven of these stars also show a few weak, isolated high frequencies and they could be considered as SPB/beta Cep hybrids. In all cases the frequency spectra are quite different from what is seen from ground-based observations. We suggest that this is because most of the low frequencies are modes of high degree which are predicted to be unstable in models of mid-B stars. We find that there are non-pulsating stars within the beta Cep and SPB instability strips. Apart from the pulsating stars, we can identify stars with frequency groupings similar to what is seen in Be stars but which are not Be stars. The origin of the groupings is not clear, but may be related to rotation. We find periodic variations in other stars which we attribute to proximity effects in binary systems or possibly rotational modulation. We find no evidence fo...

  15. Sources of Variability in Gulf of Maine Circulation, and the Observations Needed to

    E-Print Network [OSTI]

    Pringle, James "Jamie"

    Sources of Variability in Gulf of Maine Circulation, and the Observations Needed to Model it. James in the Gulf of Maine are then quantified, with an emphasis on variability on timescales longer than tidal and the volume of water entering from the Scotian Shelf to the Gulf of Maine produce roughly comparable amounts

  16. THE DUST RING OF LUMINOUS BLUE VARIABLE CANDIDATE HD 168625: INFRARED OBSERVATIONS AND MODEL CALCULATIONS1

    E-Print Network [OSTI]

    Speck, Angela Karen

    THE DUST RING OF LUMINOUS BLUE VARIABLE CANDIDATE HD 168625: INFRARED OBSERVATIONS AND MODEL surrounding the luminous blue variable (LBV) candidate HD 168625, together with new temperature and optical energy distribution of the dust. Therefore, HD 168625 is an excellent example of proposed models of LBV

  17. Biogeochemical variability in the southern Ross Sea as observed by a glider deployment

    E-Print Network [OSTI]

    Fabrizio, Mary C.

    Biogeochemical variability in the southern Ross Sea as observed by a glider deployment Daniel E­2011 austral summer identified variations in phytoplankton biomass along two glider sections near 761400 S. Sea In situ observations and satellite-derived data from the Ross Sea have revealed high phytoplankton biomass

  18. X-ray and optical variability of Seyfert 1 galaxies as observed with XMM-Newton

    E-Print Network [OSTI]

    R. Smith; S. Vaughan

    2007-01-08

    We have examined simultaneous X-ray and optical light curves of a sample of eight nearby Seyfert 1 galaxies observed using the EPIC X-ray cameras and Optical Monitor on board XMM. The observations span ~1 day and revealed optical variability in four of the eight objects studied. In all cases, the X-ray variability amplitude exceeded that of the optical both in fractional and absolute luminosity terms. No clearly significant correlations were detected between wavebands using cross correlation analysis. We conclude that, in three of the four objects in which optical variability was detected, reprocessing mechanisms between wavebands do not dominate either the optical or X-ray variability on the time-scales probed.

  19. Efficient use of simultaneous multi-band observations for variable star analysis

    E-Print Network [OSTI]

    Süveges, Maria; Becker, Andrew; Ivezic, Zeljko; Beck, Mathias; Eyer, Laurent

    2011-01-01

    The luminosity changes of most types of variable stars are correlated in the different wavelengths, and these correlations may be exploited for several purposes: for variability detection, for distinction of microvariability from noise, for period search or for classification. Principal component analysis is a simple and well-developed statistical tool to analyze correlated data. We will discuss its use on variable objects of Stripe 82 of the Sloan Digital Sky Survey, with the aim of identifying new RR Lyrae and SX Phoenicis-type candidates. The application is not straightforward because of different noise levels in the different bands, the presence of outliers that can be confused with real extreme observations, under- or overestimated errors and the dependence of errors on the magnitudes. These particularities require robust methods to be applied together with the principal component analysis. The results show that PCA is a valuable aid in variability analysis with multi-band data.

  20. Observations, Simulations, and Dynamics of Jet Stream Variability and Annular Modes JOSEPH KIDSTON

    E-Print Network [OSTI]

    Kidston, Joseph

    Observations, Simulations, and Dynamics of Jet Stream Variability and Annular Modes JOSEPH KIDSTON jet stream. It is shown that the strength of the thermally indirect circulation that gives rise- lation of the equivalent barotropic eddy-driven jet streams and embedded storm tracks (Kidson 1988; Mo

  1. Surface freshwater storage and variability in the Amazon basin from multi-satellite observations, 19932007

    E-Print Network [OSTI]

    surface water storage variations for 1993­2007 are presented, showing a strong seasonal and interannualSurface freshwater storage and variability in the Amazon basin from multi-satellite observations a hypsographic curve approach to estimate surface freshwater storage variations over the Amazon basin combining

  2. EVALUATING CLIMATE VARIABILITY AND CHANGE FROM MODERN AND HISTORICAL SST OBSERVATIONS

    E-Print Network [OSTI]

    Kaplan, Alexey

    's National Climatic Data Center, 151 Patton Avenue, Asheville, NC 28801-5001, U.S.A., Email: RichardEVALUATING CLIMATE VARIABILITY AND CHANGE FROM MODERN AND HISTORICAL SST OBSERVATIONS Nick A.W.Reynolds@noaa.gov (5) NOAA National Oceanographic Data Center, 1315 East-West Highway, Silver Spring, MD 20910, U

  3. Observed low frequency variability of the Brazil Current front Gustavo Jorge Goni,1

    E-Print Network [OSTI]

    of the Brazil Current front. Trends of eddy kinetic energy, sea height anomaly, sea surface temperature and windObserved low frequency variability of the Brazil Current front Gustavo Jorge Goni,1 Francis Bringas; published 29 October 2011. [1] The Brazil Current is a weak western boundary current, the southwest

  4. 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 [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); M, Macri Lucas; Lifan, Wang [Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX (United States); Ashley, Michael C. B.; S, Lawrence Jon; Daniel, Luong-Van [School of Physics, University of New South Wales, NSW (Australia); Xiangqun, Cui; Long-Long, Feng; Xuefei, Gong; Qiang, Liu; Huigen, Yang; Xiangyan, Yuan; Xu, Zhou; Zhenxi, Zhu [Chinese Center for Antarctic Astronomy, Nanjing (China); R, Pennypacker Carl [Center for Astrophysics, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); G, York Donald, E-mail: jnfu@bnu.edu.cn [Department of Astronomy and Astrophysics and Enrico Fermi Institute, University of Chicago, Chicago, IL (United States)

    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.

  5. Identification of RR Lyrae Variables in SDSS from Single-Epoch Photometric and Spectroscopic Observations

    E-Print Network [OSTI]

    Ronald Wilhelm; W. Lee Powell Jr.; Timothy C. Beers; Branimir Sesar; Carlos Alende Prieto; Kenneth W. Carrell; Young Sun Lee; Brian Yanny; Constance M. Rockosi; Nathan De Lee; Gwen Hansford Armstrong; Stephen J. Torrence

    2007-12-05

    We describe a new RR Lyrae identification technique based on out-of-phase single-epoch photometric and spectroscopic observations contained in SDSS Data Release 6 (DR-6). This technique detects variability by exploiting the large disparity between the g-r color and the strength of the hydrogen Balmer lines when the two observations are made at random phases. Comparison with a large sample of known variables in the SDSS equatorial stripe (Stripe 82) shows that the discovery efficiency for our technique is ~85%. Analysis of stars with multiple spectroscopic observations suggests a similar efficiency throughout the entire DR-6 sample. We also develop a technique to estimate the average g apparent magnitude (over the pulsation cycle) for individual RR Lyrae stars, using the for the entire sample and measured colors for each star. The resulting distances are found to have precisions of ~14%. Finally, we explore the properties of our DR-6 sample of N = 1087 variables, and recover portions of the Sagittarius Northern and Southern Stream. Analysis of the distance and velocity for the Southern Stream are consistent with previously published data for blue horizontal-branch stars. In a sample near the North Galactic Polar Cap, we find evidence for the descending leading Northern arm, and a possible detection of the trailing arm.

  6. SMALL-SCALE VARIABILITY IN SEA SURFACE HEIGHTS AND SURFACE WINDS: IMPLICATIONS FOR ERRORS IN OCEAN MODELS AND OBSERVATIONS

    E-Print Network [OSTI]

    Kaplan, Alexey

    SMALL-SCALE VARIABILITY IN SEA SURFACE HEIGHTS AND SURFACE WINDS: IMPLICATIONS FOR ERRORS IN OCEAN on dispersion relationship of planetary waves 4. Small-scale variability in surface winds and sea surface of model and observational data sets. Imperfect parameterization of the small-scale variability (SSV

  7. Observations of Antarctic Circumpolar Current dynamics in the Drake Passage and small-scale variability near the Antarctic Peninsula

    E-Print Network [OSTI]

    Lenn, Yueng Djern

    2006-01-01

    interesting that the migration depth appears to deepen withThe maximum depth of diel migration increased from about 80migration of zooplankton is a commonly observed behavior in which the zooplankton descend to greater depths

  8. Multiwavelength Observations of GX 339-4 in 1996. II. Rapid X-ray Variability

    E-Print Network [OSTI]

    I. A. Smith; E. P. Liang

    1998-12-08

    As part of our multiwavelength campaign of GX 339-4 observations in 1996 we present the rapid X-ray variability observed July 26 using the RXTE when the source was in a hard state (= soft X-ray low state). We found that the source was extremely variable, with many bright flares. The flares have relatively symmetric time profiles. There are a few time intervals where the flux rises steadily and then drops suddenly, sometimes to a level lower than the average before the increase. Hardness ratios showed that the source was slightly softer when the flux was brighter. The power density spectra (PDS) were also complicated and we found that broken power laws do not provide adequate fits to any of them. Instead a pair of zero-centered Lorentzians gives a good general description of the shape of the PDS. We found several quasi-periodic oscillations (QPO), including some that are harmonically spaced with the most stable frequency at 0.35 Hz. While the overall rms variability of the source was close to being constant throughout the observation (29% integrating between 0.01 and 50 Hz), there is a small but significant change in the PDS shape with time. More importantly, we show that the soft 2-5 keV band is more variable than the harder 5-10 and 10-40 keV bands, which is unusual for this source and for other black hole candidates. Cross correlation functions (CCF) between these bands show that the light curve for the 10-40 keV band lags that of the 2-5 keV band by 5 msec.

  9. Inter- and Intra-Observer Variability in Prostate Definition With Tissue Harmonic and Brightness Mode Imaging

    SciTech Connect (OSTI)

    Sandhu, Gurpreet Kaur, E-mail: Gurpreet.Sandhu2@albertahealthservices.ca [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Dunscombe, Peter [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Department of Oncology, Faculty of Medicine, University of Calgary, Calgary, Alberta (Canada); Meyer, Tyler [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Pavamani, Simon [Department of Oncology, Faculty of Medicine, University of Calgary, Calgary, Alberta (Canada); Department of Radiation Oncology, Christian Medical College, Vellore (India); Khan, Rao [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Department of Oncology, Faculty of Medicine, University of Calgary, Calgary, Alberta (Canada)

    2012-01-01

    Purpose: The objective of this study was to compare the relative utility of tissue harmonic (H) and brightness (B) transrectal ultrasound (TRUS) images of the prostate by studying interobserver and intraobserver variation in prostate delineation. Methods and Materials: Ten patients with early-stage disease were randomly selected. TRUS images of prostates were acquired using B and H modes. The prostates on all images were contoured by an experienced radiation oncologist (RO) and five equally trained observers. The observers were blinded to information regarding patient and imaging mode. The volumes of prostate glands and areas of midgland slices were calculated. Volumes contoured were compared among the observers and between observer group and RO. Contours on one patient were repeated five times by four observers to evaluate the intraobserver variability. Results: A one-sample Student t-test showed the volumes outlined by five observers are in agreement (p > 0.05) with the RO. Paired Student t-test showed prostate volumes (p = 0.008) and midgland areas (p = 0.006) with H mode were significantly smaller than that with B mode. Two-factor analysis of variances showed significant interobserver variability (p < 0.001) in prostate volumes and areas. Inter- and intraobserver consistency was quantified as the standard deviation of mean volumes and areas, and concordance indices. It was found that for small glands ({<=}35 cc) H mode provided greater interobserver consistency; however, for large glands ({>=}35 cc), B mode provided more consistent estimates. Conclusions: H mode provided superior inter- and intraobserver agreement in prostate volume definition for small to medium prostates. In large glands, H mode does not exhibit any additional advantage. Although harmonic imaging has not proven advantageous for all cases, its utilization seems to be judicious for small prostates.

  10. Nature of the Mesoscale Boundary Layer Height and Water Vapor Variability Observed 14 June 2002 during the IHOP_2002 Campaign

    E-Print Network [OSTI]

    Nature of the Mesoscale Boundary Layer Height and Water Vapor Variability Observed 14 June 2002, Boulder, Colorado (Manuscript received 4 September 2007, in final form 23 June 2008) ABSTRACT Mesoscale at the mesoscale, with the spatial pattern and the magnitude of the variability changing from day to day. On 14

  11. Variability in the Initial Costs of Care and One-Year Outcomes of Observation Services

    E-Print Network [OSTI]

    Abbass, Ibrahim

    2015-01-01

    Variability in the initial costs of care across theVariability in the Initial Costs of Care and One-Yearis associated with lower costs and comparable level of care

  12. 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.

  13. Short-term variability of suspended sediment and phytoplankton in Tampa Bay, Florida: Observations from a coastal oceanographic tower

    E-Print Network [OSTI]

    Meyers, Steven D.

    Chl increases were observed after sediment resuspension with a lag time of e1e2 days, probably due to release of bottom nutrients and optimal light conditions associated with sediment resuspension physical, chemical, and biological variability. These driving factors lead to a wide range of temporal

  14. The millimetre variability of M81* -- Multi-epoch dual frequency mm-observations of the nucleus of M81

    E-Print Network [OSTI]

    R. Schoedel; M. Krips; S. Markoff; R. Neri; A. Eckart

    2006-11-28

    There are still many open questions as to the physical mechanisms at work in Low Luminosity AGN that accrete in the extreme sub-Eddington regime. Simultaneous multi-wavelength studies have been very successful in constraining the properties of SgrA*, the extremely sub-Eddington black hole at the centre of our Milky Way. M81*, the nucleus of the nearby spiral galaxy M81, is an ideal source to extend the insights obtained on SgrA* toward higher luminosity AGN. Here we present observations at 3 and 1 mm that were obtained within the framework of a coordinated,multi-wavelength campaign on M81*. The continuum emission from M81* was observed during three epochs with the IRAM Plateau de Bure Interferometer simultaneously at wavelengths of 3 and 1 mm. We present the first flux measurements of M81* at wavelengths around 1 mm. We find that M81* is a continuously variable source with the higher variability observed at the shorter wavelength. Also, the variability at 3 and 1 mm appears to be correlated. Like SgrA*, M81* appears to display the strongest flux density and variability in the mm-to-submm regime. There remains still some ambiguity concerning the exact location of the turnover frequency from optically thick to optically thin emission. The observed variability time scales point to an upper size limit of the emitting region of the order 25 Schwarzschild radii. The data show that M81* is indeed a system with very similar physical properties to SgrA* and an ideal bridge toward high luminosity AGN. The data obtained clearly demonstrate the usefulness and, above all, the necessity of simultaneous multi-wavelength observations of LLAGN.

  15. Efficient use of simultaneous multi-band observations for variable star analysis

    E-Print Network [OSTI]

    Masci, Frank

    of microvariability from noise, for period search or for classification. Principal component analysis is a simple of Stripe 82 of the Sloan Digital Sky Survey, with the aim of identifying new RR Lyrae and SX Phoenicis. Beck and L. Eyer The results show that PCA is a valuable aid in variability analysis with multi

  16. Geographical distribution and interseasonal variability of tropical deep convection: UARS MLS observations and analyses

    E-Print Network [OSTI]

    Wang, Bin

    of water vapor maxima near the bottom of TTL are located directly above the deep convection centersGeographical distribution and interseasonal variability of tropical deep convection: UARS MLS December 2003; published 13 February 2004. [1] Tropical deep convection and its dynamical effect

  17. Quantifying the seasonal and interannual variability of North American isoprene emissions using satellite observations of the

    E-Print Network [OSTI]

    Palmer, Paul

    satellite observations of the formaldehyde column Paul I. Palmer,1,2 Dorian S. Abbot,1 Tzung-May Fu,1 Daniel isoprene emissions using satellite observations of the formaldehyde (HCHO) columns is subject to errors) to quantify the time-dependent HCHO production from isoprene, a- and b-pinenes, and methylbutenol and show

  18. Observed 20th century desert dust variability: impact on climate and biogeochemistry

    E-Print Network [OSTI]

    2010-01-01

    Understanding the 30-year Barbados desert dust record, J.tration data observed at Barbados (Prospero and Lamb, 2003)on the shorter in situ Barbados concentration data (1968 to

  19. Observational Accuracy of Variable Stars, Novae and Supernovae from Naked Eye to General Relativistic Standard: a Balance over Thousand SGQ Observations Sent to AAVSO

    E-Print Network [OSTI]

    Sigismondi, Costantino

    2015-01-01

    The theory of General Relativity deals with very accurate measurements that show significant divergences from Newtonian predictions only with speeds near to the velocity of light. An introduction for educational purposes, based on naked eye photometry, deals with the radiation near collapsing star's shells like novae and supernovae. The theme of accuracy is drafted from entry level observations to the precision of professional data, often of public domain on the web. Thousand observations of variable stars, included the type 1a SN2014J, the Nova Del 2013 and the Nova Cen 2013, sent to the AAVSO by the author, with SGQ code, during the period 1998-2015 are analyzed to increase the photometric accuracy, in the occasion of the International Year of Light 2015.

  20. The influence of selection effects on the observed cataclysmic variable population: modelling and application to the Palomar-Green sample

    E-Print Network [OSTI]

    Magaretha L. Pretorius; Christian Knigge; Ulrich Kolb

    2006-11-06

    Large differences between the properties of the known sample of cataclysmic variable stars (CVs) and the predictions of the theory of binary star evolution have long been recognised. However, because all existing CV samples suffer from strong selection effects, observational biases must be taken into account before it is possible to tell whether there is an inconsistency. In order to address this problem, we have modelled the impact of selection effects on observed CV samples using a Monte Carlo approach. By simulating the selection criteria of the Palomar-Green (PG) Survey, we show that selection effects cannot reconcile the predictions of standard CV evolution theory with the observed sample. More generally, we illustrate the effect of the biases that are introduced by magnitude limits, selection cuts in U-B, and restrictions in galactic latitude.

  1. Observed interannual variability of the Atlantic meridional overturning circulation at 26.5

    E-Print Network [OSTI]

    Carthy,1 E. Frajka-Williams,1 W. E. Johns,2 M. O. Baringer,3 C. S. Meinen,3 H. L. Bryden,1 D. Rayner,1 A. Meinen, H. L. Bryden, D. Rayner, A. Duchez, C. Roberts, and S. A. Cunningham (2012), Observed interannual (hereafter the 26 N array) [Rayner et al., 2011]. These long- term sustained measurements provide fundamental

  2. Local observability of state variables and parameters in nonlinear modeling quantified by delay reconstruction

    E-Print Network [OSTI]

    Parlitz, Ulrich; Luther, Stefan

    2015-01-01

    Features of the Jacobian matrix of the delay coordinates map are exploited for quantifying the robustness and reliability of state and parameter estimations for a given dynamical model using an observed time series. Relevant concepts of this approach are introduced and illustrated for discrete and continuous time systems employing a filtered H\\'enon map and a R\\"ossler system.

  3. Year-round observations of carbon biomass and flux variability in the Southern Ocean

    SciTech Connect (OSTI)

    Bishop, James K.B.; Wood, Todd

    2009-02-01

    Three Carbon Explorer (CE) floats profiling to kilometer depths in the Southern Ocean tracked dawn-dusk variations of mixing/stratification, particulate organic carbon (POC), and light scattering and sedimentation at 100, 250, and 800 m continuously from January 2002 to April 2003. Data were analyzed in conjunction with contemporaneous satellite winds and chlorophyll and derived subsurface light fields. The CE deployed at 66{sup o}S 172{sup o}W operated in the ice edge zone in absence of light. Two CEs deployed at 55{sup o}S 172{sup o}W recorded wintertime mixing to {approx}400 m, yet observed very different bloom dynamics and sedimentation the following spring. Four hypotheses are explored. The strongest is that shallow transient stratification of the deep winter mixed layer to shallower than photosynthetic critical depth occurred more frequently in the non-bloom/higher sedimentation case. The lower particle export to 800 m under the bloom was hypothesized to be due to higher interception of sinking carbon by a relatively starved over wintering zooplankton population. In the Southern Ocean surface phytoplankton biomass may counter indicate particle flux at kilometer depths.

  4. Observation of Strong Variability in the X-Ray Emission from Markarian 421 Correlated with the May 1996 TeV Flare

    E-Print Network [OSTI]

    Michael Schubnell

    1997-07-11

    We observed the BL Lac object Markarian 421 with the X-ray satellite RXTE and the Whipple Air Cerenkov Telescope during a two week correlated X-ray/gamma-ray campaign in May 1996. Two dramatic outbursts with extremely rapid and strong flux variations were observed at TeV energies during this period. The X-ray emission in the 2-10 keV band was highly variable and reached a peak flux of $5.6\\times10^{-10}$ erg cm$^{-2}$ s$^{-1}$, a historic high. Similar behavior was observed for the TeV emission. In contrast to earlier near-simultaneous X-ray/gamma-ray observations of Mrk 421, the variability amplitude is much larger at TeV than at X-ray energies. This behavior is expected in Synchrotron Self-Compton models.

  5. Quantifying the seasonal and interannual variability of North American isoprene emissions using satellite observations of the formaldehyde column

    E-Print Network [OSTI]

    2006-01-01

    Satellite observations of formaldehyde over North Americasatellites: Application to formaldehyde retrievals from theNorth America using formaldehyde column observations from

  6. Observations

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access to scienceSpeedingLightweight MaterialsGasObservation of aof

  7. Time-variable gravity observations of ice sheet mass balance: Precision and limitations of the GRACE satellite data

    E-Print Network [OSTI]

    Velicogna, I.; Wahr, J.

    2013-01-01

    observations, Science, 314, Peltier, W. R. (2004), Globalice history models (ICE5G [Peltier, 2004] and Fleming andfor Greenland; ICE5G [Peltier, 2004] and IJ05 [Ivins and

  8. Maximum-likelihood

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on dark matter By Sarah Schlieder *8MatthewMaximum-likelihood fitting

  9. 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.

  10. Early-type stars observed in the ESO UVES Paranal Observatory Project - V. Time-variable interstellar absorption

    E-Print Network [OSTI]

    McEvoy, Catherine M; Dufton, Philip L; Smith, Keith T; Kennedy, Michael B; Keenan, Francis P; Lambert, David L; Welty, Daniel E; Lauroesch, James T

    2015-01-01

    The structure and properties of the diffuse interstellar medium (ISM) on small scales, sub-au to 1 pc, are poorly understood. We compare interstellar absorption-lines, observed towards a selection of O- and B-type stars at two or more epochs, to search for variations over time caused by the transverse motion of each star combined with changes in the structure in the foreground ISM. Two sets of data were used: 83 VLT- UVES spectra with approximately 6 yr between epochs and 21 McDonald observatory 2.7m telescope echelle spectra with 6 - 20 yr between epochs, over a range of scales from 0 - 360 au. The interstellar absorption-lines observed at the two epochs were subtracted and searched for any residuals due to changes in the foreground ISM. Of the 104 sightlines investigated with typically five or more components in Na I D, possible temporal variation was identified in five UVES spectra (six components), in Ca II, Ca I and/or Na I absorption-lines. The variations detected range from 7\\% to a factor of 3.6 in co...

  11. ROSAT/ASCA Observations of a Serendipitous BL Lac Object PKS 2316-423: The Variable High-Energy Tail of Synchrotron Radiation

    E-Print Network [OSTI]

    Sui-Jian Xue; You-Hong Zhang; Jian-Sheng Chen

    2000-05-22

    We present the analysis of archival data from ROSAT and ASCA of a serendipitous BL Lac object PKS 2316-423. Because of its featureless non-thermal radio/optical continuum, PKS 2316-423 has been called as a BL Lac candidate in the literature. PKS 2316-423 was evidently variable over the multiple X-ray observations, in particular, a variable high-energy tail of the synchrotron radiation is revealed. The X-ray spectral analysis provides further evidence of the synchrotron nature of its broad-band spectrum: a steep and downward curving spectrum between 0.1--10 keV, typical of high-energy peaked BL Lacs (HBL). The spectral energy distribution (SED) through radio-to-X-ray yields the synchrotron radiation peak at frequency Vp=7.3 10^{15} Hz, with integrated luminosity of Lsyn=2.1 10^{44} ergs s^{-1}. The averaged SED properties of PKS 2316-423 are very similar to those ``intermediate'' BL Lac objects (IBL) found recently in several deep surveys, such as Deep X-ray Radio Blazar, Radio-Emitting X-ray, and ROSAT-Green Bank surveys. We suggest that PKS 2316-423 is an IBL though it also shows some general features of a HBL. Actually, this double attribute of PKS 2316-423 provides a good test of the prediction that an IBL object can show either synchrotron or inverse-Compton characteristics in different variability states.

  12. The Study of TeV Variability and Duty Cycle of Mrk 421 from 3 Years of Observations with the Milagro Observatory

    E-Print Network [OSTI]

    Abdo, A A; Allen, B T; Aune, T; Barber, A S; Berley, D; Braun, J; Chen, C; Christopher, G E; Delay, R S; DeYoung, T; Dingus, B L; Ellsworth, R W; Fraija, N; González, M M; Goodman, J A; Hays, E; Hoffman, C M; Hüntemeyer, P H; Imran, A; Kolterman, B E; Linnemann, J T; Marinelli, A; McEnery, J E; Morgan, T; Mincer, A I; Nemethy, P; Patricelli, B; Pretz, J; Ryan, J M; Parkinson, P M Saz; Schneider, M; Shoup, A; Sinnis, G; Smith, A J; Vasileiou, V; Walker, G P; Williams, D A; Yodh, G B

    2014-01-01

    TeV flaring activity with time scales as short as tens of minutes and an orphan TeV flare have been observed from the blazar Markarian 421 (Mrk 421). The TeV emission from Mrk 421 is believed to be produced by leptonic synchrotron self-Compton (SSC) emission. In this scenario, correlations between the X-ray and the TeV fluxes are expected, TeV orphan flares are hardly explained and the activity (measured as duty cycle) of the source at TeV energies is expected to be equal or less than that observed in X-rays if only SSC is considered. To estimate the TeV duty cycle of Mrk 421 and to establish limits on its variability at different time scales, we continuously observed Mrk 421 with the Milagro observatory. Mrk 421 was detected by Milagro with a statistical significance of 7.1 standard deviations between 2005 September 21 and 2008 March 15. The observed spectrum is consistent with previous observations by VERITAS. We estimate the duty cycle of Mrk 421 for energies above 1 TeV for different hypothesis of the bas...

  13. Maximum output at minimum cost

    E-Print Network [OSTI]

    Firestone, Jeremy

    Gamesa G90-2.0 MW #12;Maximum output at minimum cost per kWh for low wind sites ®® Class IIIA mast and the electrical substation. This innovative modular design based on TCP/IP architecture has

  14. The Origin of UV-optical Variability in AGN and Test of Disc Models: XMM-Newton and ground based observations of NGC4395

    E-Print Network [OSTI]

    McHardy, Ian; Peterson, Brad; Bieryla, Allyson; Chand, Hum; Elvis, Martin; Emmanoulopoulos, Dimitrios; Falco, Emilio; Gandhi, Poshak; Kaspi, Shai; Latham, David; Lira, Paulina; McCully, Curtis; Netzer, Hagai; Uemura, Makoto

    2016-01-01

    The origin of short timescale (weeks/months) variability of AGN, whether due to intrinsic disc variations or reprocessing of X-ray emission by a surrounding accretion disc, has been a puzzle for many years. However recently a number of observational programmes, particularly of NGC5548 with Swift, have shown that the UV/optical variations lag behind the X-ray variations in a manner strongly supportive of X-ray reprocessing. Somewhat surprisingly the implied size of the accretion disc is ~3x greater than expected from a standard, smooth, Shakura-Sunyaev thin disc model. Although the difference may be explained by a clumpy accretion disc, it is not clear whether the difference will occur in all AGN or whether it may change as, eg, a function of black hole mass, accretion rate or disc temperature. Measurements of interband lags for most AGN require long timescale monitoring, which is hard to arrange. However for low mass (solar mass) AGN, the combination of XMM-Newton EPIC (X-rays) with the optical ...

  15. Zipf's law, power laws, and maximum entropy

    E-Print Network [OSTI]

    Visser, Matt

    2012-01-01

    Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines - from astronomy to demographics to economics to linguistics to zoology, and even warfare. A recent model of random group formation [RGF] attempts a general explanation of such phenomena based on Jaynes' notion of maximum entropy applied to a particular choice of cost function. In the present article I argue that the cost function used in the RGF model is in fact unnecessarily complicated, and that power laws can be obtained in a much simpler way by applying maximum entropy ideas directly to the Shannon entropy subject only to a single constraint: that the average of the logarithm of the observable quantity is specified.

  16. SU-E-J-275: Impact of the Intra and Inter Observer Variability in the Delineation of Parotid Glands On the Dose Calculation During Head and Neck Helical Tomotherapy

    SciTech Connect (OSTI)

    Jodda, A; Piotrowski, T [Greater Poland Cancer Centre Poznan (Poland)

    2014-06-01

    Purpose: The intra- and inter-observer variability in delineation of the parotids on the kilo-voltage computed tomography (kVCT) and mega-voltage computed tomography (MVCT) were examined to establish their impact on the dose calculation during adaptive head and neck helical tomotherapy (HT). Methods: Three observers delineated left and right parotids for ten randomly selected patients with oropharynx cancer treated on HT. The pre-treatment kVCT and the MVCT from the first fraction of irradiation were selected to delineation. The delineation procedure was repeated three times by each observer. The parotids were delineated according to the institutional protocol. The analyses included intra-observer reproducibility and inter-structure, -observer and -modality variability of the volume and dose. Results: The differences between the left and right parotid outlines were not statistically significant (p>0.3). The reproducibility of the delineation was confirmed for each observer on the kVCT (p>0.2) and on the MVCT (p>0.1). The inter-observer variability of the outlines was significant (p<0.001) as well as the inter-modality variability (p<0.006). The parotids delineated on the MVCT were 10% smaller than on the kVCT. The inter-observer variability of the parotids delineation did not affect the average dose (p=0.096 on the kVCT and p=0.176 on the MVCT). The dose calculated on the MVCT was higher by 3.3% than dose from the kVCT (p=0.009). Conclusion: Usage of the institutional protocols for the parotids delineation reduces intra-observer variability and increases reproducibility of the outlines. These protocols do not eliminate delineation differences between the observers, but these differences are not clinically significant and do not affect average doses in the parotids. The volumes of the parotids delineated on the MVCT are smaller than on the kVCT, which affects the differences in the calculated doses.

  17. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2009-05-15

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  18. Maximum power tracking control scheme for wind generator systems 

    E-Print Network [OSTI]

    Mena Lopez, Hugo Eduardo

    2008-10-10

    The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

  19. Maximum-Entropy Inference with a Programmable Annealer

    E-Print Network [OSTI]

    Chancellor, Nicholas; Vinci, Walter; Aeppli, Gabriel; Warburton, Paul A

    2015-01-01

    Optimisation problems in science and engineering typically involve finding the ground state (i.e. the minimum energy configuration) of a cost function with respect to many variables. If the variables are corrupted by noise then this approach maximises the likelihood that the solution found is correct. An alternative approach is to make use of prior statistical information about the noise in conjunction with Bayes's theorem. The maximum entropy solution to the problem then takes the form of a Boltzmann distribution over the ground and excited states of the cost function. Here we use a programmable Josephson junction array for the information decoding problem which we simulate as a random Ising model in a field. We show experimentally that maximum entropy decoding at finite temperature can in certain cases give competitive and even slightly better bit-error-rates than the maximum likelihood approach at zero temperature, confirming that useful information can be extracted from the excited states of the annealing...

  20. Maximum entropy analysis of cosmic ray composition

    E-Print Network [OSTI]

    Nosek, Dalibor; Vícha, Jakub; Trávní?ek, Petr; Nosková, Jana

    2016-01-01

    We focus on the primary composition of cosmic rays with the highest energies that cause extensive air showers in the Earth's atmosphere. A way of examining the two lowest order moments of the sample distribution of the depth of shower maximum is presented. The aim is to show that useful information about the composition of the primary beam can be inferred with limited knowledge we have about processes underlying these observations. In order to describe how the moments of the depth of shower maximum depend on the type of primary particles and their energies, we utilize a superposition model. Using the principle of maximum entropy, we are able to determine what trends in the primary composition are consistent with the input data, while relying on a limited amount of information from shower physics. Some capabilities and limitations of the proposed method are discussed. In order to achieve a realistic description of the primary mass composition, we pay special attention to the choice of the parameters of the sup...

  1. Boiler Maximum Achievable Control Technology (MACT) Technical...

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

    Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact Sheet, April 2015 Boiler Maximum Achievable Control Technology (MACT) Technical Assistance - Fact...

  2. Objects of maximum electromagnetic chirality

    E-Print Network [OSTI]

    Fernandez-Corbaton, Ivan

    2015-01-01

    We introduce a definition of the electromagnetic chirality of an object and show that it has an upper bound. The upper bound is attained if and only if the object is transparent for fields of one handedness (helicity). Additionally, electromagnetic duality symmetry, i.e. helicity preservation upon scattering, turns out to be a necessary condition for reciprocal scatterers to attain the upper bound. We use these results to provide requirements for the design of such extremal scatterers. The requirements can be formulated as constraints on the polarizability tensors for dipolar scatterers or as material constitutive relations. We also outline two applications for objects of maximum electromagnetic chirality: A twofold resonantly enhanced and background free circular dichroism measurement setup, and angle independent helicity filtering glasses.

  3. Maximum entanglement in squeezed boson and fermion states

    SciTech Connect (OSTI)

    Khanna, F. C. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Malbouisson, J. M. C. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Salvador, BA (Brazil); Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Santana, A. E. [Instituto de Fisica, Universidade de Brasilia, 70910-900, Brasilia, DF (Brazil); Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Santos, E. S. [Centro Federal de Educacao Tecnologica da Bahia, 40030-010, Salvador, BA (Brazil)

    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.

  4. Max '91: flare research at the next solar maximum

    SciTech Connect (OSTI)

    Dennis, B.; Canfield, R.; Bruner, M.; Emslie, G.; Hildner, E.; Hudson, H.; Hurford, G.; Lin, R.; Novick, R.; Tarbell, T.

    1988-01-01

    To address the central scientific questions surrounding solar flares, coordinated observations of electromagnetic radiation and energetic particles must be made from spacecraft, balloons, rockets, and ground-based observatories. A program to enhance capabilities in these areas in preparation for the next solar maximum in 1991 is recommended. The major scientific issues are described, and required observations and coordination of observations and analyses are detailed. A program plan and conceptual budgets are provided.

  5. The maximum multiflow problems with bounded fractionality

    E-Print Network [OSTI]

    Hirai, Hiroshi

    (Karzanov 98) frac(| ) = frac(K2 + Kn) = 4 (Lomonsov 04) frac( ) =? Hiroshi Hirai The maximum multiflow

  6. The X-ray spectra and spectral variability of intermediate type Seyfert galaxies: ASCA observations of NGC 4388 and ESO 103-G35

    E-Print Network [OSTI]

    Karl Forster; Karen M. Leighly; Laura E. Kay

    1999-03-28

    The X-ray spectra of two intermediate type Seyfert galaxies are investigated using ASCA observations separated by more than a year. Both NGC 4388 and ESO 103-G35 exhibit strong, narrow Fe K alpha line emission and absorption by cold neutral gas with a column density ~ 10^23 cm^-2, characteristic of the X-ray spectra of type 2 Seyfert galaxies. The power law continuum flux has changed by a factor of 2 over a time-scale of ~ 2 years for both objects, declining in the case of NGC 4388 and rising in ESO 103-G35. No variation was observed in the equivalent width of the Fe K alpha line in the spectra of NGC 4388, implying that the line flux declined with the continuum. We find that the strength of the line cannot be accounted for by fluorescence in line-of-sight material with the measured column density unless a `leaky-absorber' model of the type favored for IRAS 04575-7537 is employed. The equivalent width of the Fe K alpha emission line is seen to decrease between the observations of ESO 103-G35 while the continuum flux increased. The 1996 observation of ESO 103-G35 can also be fitted with an absorption edge at 7.4 $\\pm$ 0.2 keV due to partially ionized iron, and when an ionized absorber model is fitted to the data it is found that the equivalent column of neutral hydrogen rises to 3.5 x 10^23 cm^-2. The Fe K alpha line flux can be accounted by fluorescence in this material alone and this model is also a good representation of the 1988 and 1991 Ginga observations. There is then no requirement for a reflection component in the ASCA spectra of ESO 103-G35 or NGC 4388.

  7. Tree-ring reconstruction of maximum and minimum temperatures

    E-Print Network [OSTI]

    -width (RW) and maximum density (MXD) series from treeline sites across Interior British Columbia. Multi- ple at these temperature-limited sites may be more closely related to Tmax than Tmean or Tmin; (3) recently reported in the relationships between ring-width (RW), maxi- mum latewood density (MXD) and May-August Tmean were observed

  8. Maximum-likelihood density modification

    SciTech Connect (OSTI)

    Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov [Structural Biology Group, Mail Stop M888, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2000-08-01

    A likelihood-based density modification approach is developed that can incorporate expected electron-density information from a wide variety of sources. A likelihood-based approach to density modification is developed that can be applied to a wide variety of cases where some information about the electron density at various points in the unit cell is available. The key to the approach consists of developing likelihood functions that represent the probability that a particular value of electron density is consistent with prior expectations for the electron density at that point in the unit cell. These likelihood functions are then combined with likelihood functions based on experimental observations and with others containing any prior knowledge about structure factors to form a combined likelihood function for each structure factor. A simple and general approach to maximizing the combined likelihood function is developed. It is found that this likelihood-based approach yields greater phase improvement in model and real test cases than either conventional solvent flattening and histogram matching or a recent reciprocal-space solvent-flattening procedure [Terwilliger (1999 ?), Acta Cryst. D55, 1863–1871].

  9. NGC2613, 3198, 6503, 7184: Case studies against `maximum' disks

    E-Print Network [OSTI]

    B. Fuchs

    1998-12-02

    Decompositions of the rotation curves of NGC2613, 3198, 6505, and 7184 are analysed. For these galaxies the radial velocity dispersions of the stars have been measured and their morphology is clearly discernible. If the parameters of the decompositions are chosen according to the `maximum' disk hypothesis, the Toomre Q stability parameter is systematically less than one and the multiplicities of the spiral arms as expected from density wave theory are inconsitent with the observed morphologies of the galaxies. The apparent Q<1 instability, in particular, is a strong argument against the `maximum' disk hypothesis.

  10. Maximum-Entropy Inference with a Programmable Annealer

    E-Print Network [OSTI]

    Nicholas Chancellor; Szilard Szoke; Walter Vinci; Gabriel Aeppli; Paul A. Warburton

    2015-06-26

    Optimisation problems in science and engineering typically involve finding the ground state (i.e. the minimum energy configuration) of a cost function with respect to many variables. If the variables are corrupted by noise then this approach maximises the likelihood that the solution found is correct. An alternative approach is to make use of prior statistical information about the noise in conjunction with Bayes's theorem. The maximum entropy solution to the problem then takes the form of a Boltzmann distribution over the ground and excited states of the cost function. Here we use a programmable Josephson junction array for the information decoding problem which we simulate as a random Ising model in a field. We show experimentally that maximum entropy decoding at finite temperature can in certain cases give competitive and even slightly better bit-error-rates than the maximum likelihood approach at zero temperature, confirming that useful information can be extracted from the excited states of the annealing device. Furthermore we introduce a microscopic bit-by-bit analytical method which is agnostic to the specific application and use it to show that the annealing device samples from a highly Boltzmann-like distribution. Machines of this kind are therefore candidates for use in a wide variety of machine learning applications which exploit maximum entropy inference, including natural language processing and image recognition. We further show that the limiting factor for performance in our experiments is likely to be control errors rather than failure to reach equilibrium. Our work also provides a method for determining if a system is in equilibrium which can be easily generalized. We discuss possible applications of this method to spin glasses and probing the performance of the quantum annealing algorithm.

  11. Maximum-Likelihood Stereo Correspondence using Field

    E-Print Network [OSTI]

    MacLean, W. James

    Maximum-Likelihood Stereo Correspondence using Field Programmable Gate Arrays Siraj Sabihuddin & W. James MacLean Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario be performed using a maximum- likelihood formulation. One such formulation has been presented by Cox [1], who

  12. MAXIMUM ENTROPY APPROACH TO OPTIMAL SENSOR PLACEMENT

    E-Print Network [OSTI]

    Kreinovich, Vladik

    MAXIMUM ENTROPY APPROACH TO OPTIMAL SENSOR PLACEMENT FOR AEROSPACE NON-DESTRUCTIVE TESTING R discussed for space struc- tures. Key words: Non-destructive testing, maximum entropy, aerospace structures not have a sufficient number of them, so additional sensors must be placed to test the structural integrity

  13. Maximum entropy method for reconstruction of the CMB images

    E-Print Network [OSTI]

    A. T. Bajkova

    2002-05-21

    We propose a new approach for the accurate reconstruction of cosmic microwave background distributions from observations containing in addition to the primary fluctuations the radiation from unresolved extragalactic point sources and pixel noise. The approach uses some effective realizations of the well-known maximum entropy method and principally takes into account {\\it a priori} information about finiteness and spherical symmetry of the power spectrum of the CMB satisfying the Gaussian statistics.

  14. Cell development obeys maximum Fisher information

    E-Print Network [OSTI]

    B. R. Frieden; R. A. Gatenby

    2014-04-29

    Eukaryotic cell development has been optimized by natural selection to obey maximal intracellular flux of messenger proteins. This, in turn, implies maximum Fisher information on angular position about a target nuclear pore complex (NPR). The cell is simply modeled as spherical, with cell membrane (CM) diameter 10 micron and concentric nuclear membrane (NM) diameter 6 micron. The NM contains about 3000 nuclear pore complexes (NPCs). Development requires messenger ligands to travel from the CM-NPC-DNA target binding sites. Ligands acquire negative charge by phosphorylation, passing through the cytoplasm over Newtonian trajectories toward positively charged NPCs (utilizing positive nuclear localization sequences). The CM-NPC channel obeys maximized mean protein flux F and Fisher information I at the NPC, with first-order delta I = 0 and approximate 2nd-order delta I = 0 stability to environmental perturbations. Many of its predictions are confirmed, including the dominance of protein pathways of from 1-4 proteins, a 4nm size for the EGFR protein and the approximate flux value F =10^16 proteins/m2-s. After entering the nucleus, each protein ultimately delivers its ligand information to a DNA target site with maximum probability, i.e. maximum Kullback-Liebler entropy HKL. In a smoothness limit HKL approaches IDNA/2, so that the total CM-NPC-DNA channel obeys maximum Fisher I. Thus maximum information approaches non-equilibrium, one condition for life.

  15. GEOMAGNETIC EFFECTS OF INTERPLANETARY SHOCK WAVES DURING SOLAR MINIMUM (1995-1996) AND SOLAR MAXIMUM (2000)

    E-Print Network [OSTI]

    2000-01-01

    GEOMAGNETIC EFFECTS OF INTERPLANETARY SHOCK WAVES DURING SOLAR MINIMUM (1995-1996) AND SOLAR during solar minimum (1995-1996) and solar maximum (2000) periods are obtained. It is observed that solar significant correlations during both solar maximum and solar minimum. The dynamic pressure variation, however

  16. Carbon monoxide (CO) maximum over the Zagros mountains in the Middle East: Signature of mountain venting?

    E-Print Network [OSTI]

    Jones, Dylan

    Carbon monoxide (CO) maximum over the Zagros mountains in the Middle East: Signature of mountain- posphere (MOPITT) satellite instrument. Enhanced CO is observed over the Zagros mountains of Iran), Carbon monoxide (CO) maximum over the Zagros mountains in the Middle East: Signature of mountain venting

  17. Cataclysmic Variables

    E-Print Network [OSTI]

    Robert Connon Smith

    2007-01-23

    Cataclysmic variables are binary stars in which a relatively normal star is transferring mass to its compact companion. This interaction gives rise to a rich range of behaviour, of which the most noticeable are the outbursts that give the class its name. Novae belong to the class, as do the less well known dwarf novae and magnetic systems. Novae draw their energy from nuclear reactions, while dwarf novae rely on gravity to power their smaller eruptions. All the different classes of cataclysmic variable can be accommodated within a single framework and this article will describe the framework, review the properties of the main types of system and discuss models of the outbursts and of the long-term evolution.

  18. 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.

  19. Bayesian and Maximum Likelihood Neural Networks

    E-Print Network [OSTI]

    Nielsen, Finn Årup

    Bayesian and Maximum Likelihood Neural Networks Finn A ffi rup Nielsen Section for Digital Signal, linear output, Gaussian distribution ] \\Gamma 1;+1[ ffl Binary (binary classification), tanh on output, bino­ mial distribution. ] \\Gamma 1; +1[ ffl Classification, softmax function on outputs [Bridle, 1990

  20. Partitioned algorithms for maximum likelihood and

    E-Print Network [OSTI]

    Smyth, Gordon K.

    Partitioned algorithms for maximum likelihood and other nonlinear estimation Gordon K. Smyth There are a variety of methods in the literature which seek to make iterative estimation algorithms more manageable by breaking the iterations into a greater number of simpler or faster steps. Those algorithms which deal

  1. On maximum matching width Jisu Jeong (KAIST)

    E-Print Network [OSTI]

    Kim, Yong Jung

    ;Graph width parameters · tree-width (Halin 1976, Robertson and Seymour 1984) · branch-width (Robertson and Seymour 1991) · carving-width (Seymour and Thomas 1994) · clique-width (Courcelle and Olariu 2000) · rank-width (Oum and Seymour 2006) · maximum matching-width (Vatshelle 2012) #12;a b c d e fg hi j A tree

  2. NOAA Technical Memorandum NMFS-SEFSC-570 ESTIMATION OF EFFORT, MAXIMUM SUSTAINABLE YIELD, AND MAXIMUM

    E-Print Network [OSTI]

    , AND MAXIMUM ECONOMIC YIELD IN THE SHRIMP FISHERY OF THE GULF OF MEXICO BY JAMES NANCE, WALTER KEITHLY, JR YIELD, AND MAXIMUM ECONOMIC YIELD IN THE SHRIMP FISHERY OF THE GULF OF MEXICO BY JAMES NANCE, WALTER in the shrimp fishery of the Gulf of Mexico. NOAA Technical Memorandum NMFS-SEFSC-570, 71P. Copies may

  3. Maximum Estrada Index of Bicyclic Graphs

    E-Print Network [OSTI]

    Wang, Long; Wang, Yi

    2012-01-01

    Let $G$ be a simple graph of order $n$, let $\\lambda_1(G),\\lambda_2(G),...,\\lambda_n(G)$ be the eigenvalues of the adjacency matrix of $G$. The Esrada index of $G$ is defined as $EE(G)=\\sum_{i=1}^{n}e^{\\lambda_i(G)}$. In this paper we determine the unique graph with maximum Estrada index among bicyclic graphs with fixed order.

  4. Generalized Maximum Likelihood Method for Ultrahigh Energy Cosmic Rays

    E-Print Network [OSTI]

    Glennys R. Farrar

    2008-10-01

    The Maximum Likelihood Method is generalized to include effects important for UHECR applications. The new approach can incorporate source distance constraints implied by the observed CR energy and can allow for energy uncertainties, possible deflection in magnetic fields, multiple source types, and a spectrum of CR composition. It can be efficiently implemented and does not require the unphysical "isotropic" assumption for unidentified sources. The approach optimizes the utility of UHECR data to discriminate between source classes and can help constrain galactic and extragalactic magnetic fields. Aspects of the method are directly applicable in other contexts, such as TeV gamma ray astrophysics.

  5. Maximum total organic carbon limit for DWPF melter feed

    SciTech Connect (OSTI)

    Choi, A.S.

    1995-03-13

    DWPF recently decided to control the potential flammability of melter off-gas by limiting the total carbon content in the melter feed and maintaining adequate conditions for combustion in the melter plenum. With this new strategy, all the LFL analyzers and associated interlocks and alarms were removed from both the primary and backup melter off-gas systems. Subsequently, D. Iverson of DWPF- T{ampersand}E requested that SRTC determine the maximum allowable total organic carbon (TOC) content in the melter feed which can be implemented as part of the Process Requirements for melter feed preparation (PR-S04). The maximum TOC limit thus determined in this study was about 24,000 ppm on an aqueous slurry basis. At the TOC levels below this, the peak concentration of combustible components in the quenched off-gas will not exceed 60 percent of the LFL during off-gas surges of magnitudes up to three times nominal, provided that the melter plenum temperature and the air purge rate to the BUFC are monitored and controlled above 650 degrees C and 220 lb/hr, respectively. Appropriate interlocks should discontinue the feeding when one or both of these conditions are not met. Both the magnitude and duration of an off-gas surge have a major impact on the maximum TOC limit, since they directly affect the melter plenum temperature and combustion. Although the data obtained during recent DWPF melter startup tests showed that the peak magnitude of a surge can be greater than three times nominal, the observed duration was considerably shorter, on the order of several seconds. The long surge duration assumed in this study has a greater impact on the plenum temperature than the peak magnitude, thus making the maximum TOC estimate conservative. Two models were used to make the necessary calculations to determine the TOC limit.

  6. 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...

  7. Maximum Performance Group MPG | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation, searchScotland JumpPlantation Elec Co JumpIAEAOpenMaximum

  8. Variable Valve Actuation

    SciTech Connect (OSTI)

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the mechanism it was determined that the single cam design did not have enough flexibility to satisfy three critical OEM requirements simultaneously, (maximum valve lift variation, intake valve opening timing and valve closing duration), and a new approach would be necessary. After numerous internal design reviews including several with the OEM a dual cam design was developed that had the flexibility to meet all motion requirements. The second cam added complexity to the mechanism however the cost was offset by the deletion of the electric motor required in the previous design. New patent applications including detailed drawings and potential valve motion profiles were generated and alternate two cam designs were proposed and evaluated for function, cost, reliability and durability. Hardware was designed and built and testing of sample hardware was successfully completed on an engine test stand. The mechanism developed during the course of this investigation can be applied by Original Equipment Manufacturers, (OEM), to their advanced diesel engines with the ultimate goal of reducing emissions and improving fuel economy. The objectives are: (1) Develop an optimal, cost effective, variable valve actuation (VVA) system for advanced low temperature diesel combustion processes. (2) Design and model alternative mechanical approaches and down-select for optimum design. (3) Build and demonstrate a mechanism capable of application on running engines.

  9. Maximum Likelihood Signal Extraction Method Applied to 3.4 years of CoGeNT Data

    E-Print Network [OSTI]

    C. E. Aalseth; P. S. Barbeau; J. Diaz Leon; J. E. Fast; T. W. Hossbach; A. Knecht; M. S. Kos; M. G. Marino; H. S. Miley; M. L. Miller; J. L. Orrell

    2015-02-05

    CoGeNT has taken data for over 3 years, with 1136 live days of data accumulated as of April 23, 2013. We report on the results of a maximum likelihood analysis to extract any possible dark matter signal present in the collected data. The maximum likelihood signal extraction uses 2-dimensional probability density functions (PDFs) to characterize the anticipated variations in dark matter interaction rates for given observable nuclear recoil energies during differing periods of the Earth's annual orbit around the Sun. Cosmogenic and primordial radioactivity backgrounds are characterized by their energy signatures and in some cases decay half-lives. A third parameterizing variable -- pulse rise-time -- is added to the likelihood analysis to characterize slow rising pulses described in prior analyses. The contribution to each event category is analyzed for various dark matter signal hypotheses including a dark matter standard halo model and a case with free oscillation parameters (i.e., amplitude, period, and phase). The best-fit dark matter signal is in close proximity to previously reported results. We find that the significance of the extracted dark matter signal remains well below evidentiary at 1.7 $\\sigma$.

  10. 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.

  11. Statistical optimization for passive scalar transport: maximum entropy production vs maximum Kolmogorov-Sinay entropy

    E-Print Network [OSTI]

    Martin Mihelich; Berengere Dubrulle; Didier Paillard; Davide Faranda

    2015-05-26

    We derive rigorous results on the link between the principle of maximum entropy production and the principle of maximum Kolmogorov-Sinai entropy using a Markov model of the passive scalar diffusion called the Zero Range Process. We show analytically that both the entropy production and the Kolmogorov-Sinai entropy seen as functions of f admit a unique maximum denoted fmaxEP and fmaxKS. The behavior of these two maxima is explored as a function of the system disequilibrium and the system resolution N. The main result of this article is that fmaxEP and fmaxKS have the same Taylor expansion at _rst order in the deviation of equilibrium. We find that fmaxEP hardly depends on N whereas fmaxKS depends strongly on N. In particular, for a fixed difference of potential between the reservoirs, fmaxEP (N) tends towards a non-zero value, while fmaxKS (N) tends to 0 when N goes to infinity. For values of N typical of that adopted by Paltridge and climatologists we show that fmaxEP and fmaxKS coincide even far from equilibrium. Finally, we show that one can find an optimal resolution N_ such that fmaxEP and fmaxKS coincide, at least up to a second order parameter proportional to the non-equilibrium uxes imposed to the boundaries.

  12. What measures climate? A variety of variables including their variability and extreme values determine climate for

    E-Print Network [OSTI]

    Allan, Richard P.

    climate zones? The sun is the ultimate power source for the climate "machine". The uneven distribution conditions. Typical variables to consider are temperature (maximum, miniumum), precipitation (includes rain, sleet, snow, hail, etc), sunlight/cloudiness, wind, humidity, ice cover, sea temperature, etc... Many

  13. Quantum Mechanics Without Observers

    E-Print Network [OSTI]

    W. H. Sulis

    2013-03-03

    The measurement problem and the role of observers have plagued quantum mechanics since its conception. Attempts to resolve these have introduced anthropomorphic or non-realist notions into physics. A shift of perspective based upon process theory and utilizing methods from combinatorial games, interpolation theory and complex systems theory results in a novel realist version of quantum mechanics incorporating quasi-local, nondeterministic hidden variables that are compatible with the no-hidden variable theorems and relativistic invariance, and reproduce the standard results of quantum mechanics to a high degree of accuracy without invoking observers.

  14. On the "viscosity maximum" during the uniaxial extension of a low density polyethylene

    E-Print Network [OSTI]

    Teodor I. Burghelea; Zdenek Stary; Helmut Muenstedt

    2010-01-13

    An experimental investigation of the viscosity overshoot phenomenon observed during uniaxial extension of a low density polyethylene is pre- sented. For this purpose, traditional integral viscosity measurements on a Muenstedt type extensional rheometer are combined with local mea- surements based on the in-situ visualization of the sample under exten- sion. For elongational experiments at constant strain rates within a wide range of Weissenberg numbers (Wi), three distinct deformation regimes are identified. Corresponding to low values of Wi (regime I), the tensile stress displays a broad maximum. This maximum can be explained by simple mathematical arguments as a result of low deformation rates and it should not be confused with the viscosity overshoot phenomenon. Corre- sponding to intermediate values of Wi (regime II), a local maximum of the integral extensional viscosity is systematically observed. However, within this regime, the local viscosity measurements reveal no maximum, but a plateau. Careful inspection of the images of samples within this regime shows that, corresponding to the maximum of the integral viscosity, sec- ondary necks develop along the sample. The emergence of a maximum of the integral elongational viscosity is thus related to the distinct in- homogeneity of deformation states and is not related to the rheological properties of the material. In the fast stretching limit (high Wi, regime III), the overall geometric uniformity of the sample is well preserved, no secondary necks are observed and both the integral and the local transient elongational viscosity show no maximum. A detailed comparison of the experimental findings with results from literature is presented.

  15. Spectral Modeling of SNe Ia Near Maximum Light: Probing the Characteristics of Hydro Models

    E-Print Network [OSTI]

    E. Baron; S. Bongard; David Branch; Peter H. Hauschildt

    2006-03-03

    We have performed detailed NLTE spectral synthesis modeling of 2 types of 1-D hydro models: the very highly parameterized deflagration model W7, and two delayed detonation models. We find that overall both models do about equally well at fitting well observed SNe Ia near to maximum light. However, the Si II 6150 feature of W7 is systematically too fast, whereas for the delayed detonation models it is also somewhat too fast, but significantly better than that of W7. We find that a parameterized mixed model does the best job of reproducing the Si II 6150 line near maximum light and we study the differences in the models that lead to better fits to normal SNe Ia. We discuss what is required of a hydro model to fit the spectra of observed SNe Ia near maximum light.

  16. Maximum gravitational-wave energy emissible in magnetar flares

    E-Print Network [OSTI]

    Alessandra Corsi; Benjamin J. Owen

    2011-02-16

    Recent searches of gravitational-wave (GW) data raise the question of what maximum GW energies could be emitted during gamma-ray flares of highly magnetized neutron stars (magnetars). The highest energies (\\sim 10^{49} erg) predicted so far come from a model [K. Ioka, Mon. Not. Roy. Astron. Soc. 327, 639 (2001)] in which the internal magnetic field of a magnetar experiences a global reconfiguration, changing the hydromagnetic equilibrium structure of the star and tapping the gravitational potential energy without changing the magnetic potential energy. The largest energies in this model assume very special conditions, including a large change in moment of inertia (which was observed in at most one flare), a very high internal magnetic field, and a very soft equation of state. Here we show that energies of 10^{48}-10^{49} erg are possible under more generic conditions by tapping the magnetic energy, and we note that similar energies may also be available through cracking of exotic solid cores. Current observational limits on gravitational waves from magnetar fundamental modes are just reaching these energies and will beat them in the era of advanced interferometers.

  17. Variable Frequency Pump Drives 

    E-Print Network [OSTI]

    Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.

    1986-01-01

    variable flow operation, Fig. 2 variable system head, the objective of the latter being to maintain pump flow within an optimum range while accommodating a wide variation in system head. VARYING OPERATING CAPACITY OPERATING CAPACITY? N, RANGE HEAD...-rotor motors and variable speed devices have slip losses that significantly reduce the savings that accrue by operating pumps at variable speed. Steam turbine drives may not always be the most practical or economic solution. The variable frequency...

  18. The Maximum Mass of a Neutron Star

    E-Print Network [OSTI]

    Vassiliki Kalogera; Gordon Baym

    1996-08-11

    Observational identification of black holes as members of binary systems requires the knowledge of the upper limit on the gravitational mass of a neutron star. We use modern equations of state for neutron star matter, fitted to experimental nucleon-nucleon scattering data and the properties of light nuclei, to calculate, within the framework of Rhoades & Ruffini (1974), the minimum upper limit on a neutron star mass. Regarding the equation of state as valid up to twice nuclear matter saturation density, rho_{nm}, we obtain a secure upper bound on the neutron star mass equal to 2.9 solar masses. We also find that in order to reach the lowest possible upper bound of 2.2 solar masses, we need understand the physical properties of neutron matter up to a density of about 4 times rho_{nm}.

  19. Low-energy particle response to CMEs during the Ulysses solar maximum northern polar passage

    E-Print Network [OSTI]

    Sanahuja, Blai

    Low-energy particle response to CMEs during the Ulysses solar maximum northern polar passage D, New Mexico, USA T. R. Sanderson Research and Scientific Support Department of European Space Agency 2001), Ulysses remained immersed in polar coronal hole solar wind flow and observed five intense solar

  20. Maximum entropy generation in open systems: the Fourth Law?

    E-Print Network [OSTI]

    Umberto Lucia

    2010-11-17

    This paper develops an analytical and rigorous formulation of the maximum entropy generation principle. The result is suggested as the Fourth Law of Thermodynamics.

  1. Maximum-principle-satisfying second order discontinuous Galerkin ...

    E-Print Network [OSTI]

    2014-05-05

    Notice that the CFL conditions in Table 2.1 are sufficient but not necessary to achieve maximum principle. A more efficient implementation would be enforcing

  2. EERE Takes Important Steps to Ensure Maximum Impact of Technology...

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

    in wind, solar and other programs is essential to achieve maximum return for taxpayer investment. | Photos courtesy of the National Renewable Energy Laboratory Tracking...

  3. AUV Observations of the Diurnal Surface Layer in the North Atlantic3 Salinity Maximum4

    E-Print Network [OSTI]

    Fratantoni, David

    stabilizing effect of the thermal stratification then inhibits convection and vertical mixing,39 allowing typically53 #12; 4 display little stratification in the upper meter, even under low-wind, high

  4. The Multi-Mission Maximum Likelihood framework (3ML)

    E-Print Network [OSTI]

    Vianello, Giacomo; Younk, Patrick; Tibaldo, Luigi; Burgess, James M; Ayala, Hugo; Harding, Patrick; Hui, Michelle; Omodei, Nicola; Zhou, Hao

    2015-01-01

    Astrophysical sources are now observed by many different instruments at different wavelengths, from radio to high-energy gamma-rays, with an unprecedented quality. Putting all these data together to form a coherent view, however, is a very difficult task. Each instrument has its own data format, software and analysis procedure, which are difficult to combine. It is for example very challenging to perform a broadband fit of the energy spectrum of the source. The Multi-Mission Maximum Likelihood framework (3ML) aims to solve this issue, providing a common framework which allows for a coherent modeling of sources using all the available data, independent of their origin. At the same time, thanks to its architecture based on plug-ins, 3ML uses the existing official software of each instrument for the corresponding data in a way which is transparent to the user. 3ML is based on the likelihood formalism, in which a model summarizing our knowledge about a particular region of the sky is convolved with the instrument...

  5. Predicting Customer Behavior using Naive Bayes and Maximum Entropy

    E-Print Network [OSTI]

    Keysers, Daniel

    of returned goods, we additionally generated two binary features for zero and missing values. The remaining Naive Bayes, Maximum Entropy, Neural Networks and Logistic Regression for classification of cus- tomer classifiers won the Data-Mining-Cup in 2004. Combining Logistic Regression, Neural Networks, and Maximum

  6. Maximum oxidative phosphorylation capacity of the mammalian heart

    E-Print Network [OSTI]

    Mootha, Vamsi K.

    Maximum oxidative phosphorylation capacity of the mammalian heart VAMSI K. MOOTHA, ANDREW E. ARAI, AND ROBERT S. BALABAN Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National. Maximum oxidative phosphorylation capacity of the mammalian heart. Am. J. Physiol. 272 (Heart Circ

  7. Ashtekar's variables without spin

    E-Print Network [OSTI]

    Thomas Schucker

    2009-06-26

    Ashtekar's variables are shown to arise naturally from a 3+1 split of general relativity in the Einstein-Cartan formulation. Thereby spinors are exorcised.

  8. Maximum Instantaneous Power Estimation by Subgraph Coloring UCSD CSE Dept.

    E-Print Network [OSTI]

    Liu, Bao

    cycle helps in building a maximum envelope currents waveform for each net and providing a MIP upper process technology advancement integrates millions of gates on a single chip and introduces increasing

  9. Multi-Class Classification with Maximum Margin Multiple Kernel

    E-Print Network [OSTI]

    Mohri, Mehryar

    (named OBSCURE and UFO-MKL, respectively) are used to optimize primal versions of equivalent problems), the OBSCURE and UFO-MKL algorithms are compared against MCMKL #12;Multi-Class Classification with Maximum

  10. A magmatic trigger for the Paleocene-Eocene thermal maximum?

    E-Print Network [OSTI]

    Dubin, Andrea Rose

    2015-01-01

    Fifty-six million years ago Earth experienced rapid global warming (~6°C) that was caused by the release of large amounts of carbon into the ocean-atmosphere system. This Paleocene-Eocene Thermal Maximum (PETM) is often ...

  11. Maximum likelihood analysis of low energy CDMS II germanium data

    E-Print Network [OSTI]

    Agnese, R.

    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 ...

  12. Maximum containment : the most controversial labs in the world

    E-Print Network [OSTI]

    Bruzek, Alison K. (Allison Kim)

    2013-01-01

    In 2002, following the September 11th attacks and the anthrax letters, the United States allocated money to build two maximum containment biology labs. Called Biosafety Level 4 (BSL-4) facilities, these labs were built to ...

  13. 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.

  14. Filtering Additive Measurement Noise with Maximum Entropy in the Mean

    E-Print Network [OSTI]

    Henryk Gzyl; Enrique ter Horst

    2007-09-04

    The purpose of this note is to show how the method of maximum entropy in the mean (MEM) may be used to improve parametric estimation when the measurements are corrupted by large level of noise. The method is developed in the context on a concrete example: that of estimation of the parameter in an exponential distribution. We compare the performance of our method with the bayesian and maximum likelihood approaches.

  15. Nonparametric estimation of econometric models with categorical variables 

    E-Print Network [OSTI]

    Ouyang, Desheng

    2006-10-30

    shows that regression model with only discrete vari- ables differs significantly from the mixed discrete and continuous variables case. In the mixed variable case with at least one relevant continuous regressor, the irrele- vant variables can be smoothed... CV-based estimator has a high probability of smoothing out the irrele- vant variable, hence it leads to a more efficient (in finite samples) estimation result than the frequency estimator. It is interesting to observe that our nonparametric CV...

  16. Heat rate and maximum load capability improvements through cycle isolation

    SciTech Connect (OSTI)

    Coons, K. [Coronado Generating Station, Saint Johns, AZ (United States); Dimmick, J.G. [Leak Detection Services, Inc., Annapolis, MD (United States)

    1995-06-01

    Major improvements in maximum load capability and gross turbine heat rate were obtained at Salt River Project`s Coronado Unit 1, resulting from work done during the Spring 1993 overhaul. Corrected maximum load increased by 13.1 MW -- from 403.8 MW prior to the overhaul compared to 416.9 MW after the overhaul. Corrected gross turbine heat rate was reduced 270 BTU/kWH -- from 7,920 BTU/kWH before the overhaul to 7,650 BTU/kWH after the overhaul. Of the work done, the repair of leaking valves had the largest impact on cycle performance. The reduction of cycle leakage accounted for an increase of 9.9 MW in maximum load capability and a reduction to gross turbine heat rate of 190 BTU. Weekly maximum load tests, which started in August 1992 with the installation of an on-line monitoring system, show that maximum load had decreased approximately 4 MW during the six months prior to the overhaul. During this time there were no significant changes in HP or IP efficiencies, or any other directly-measured cycle parameters. Therefore, this degradation was attributed to cycle isolation valve leakage. Acoustic emission leak detection methods were used to identify leaking valves prior to the outage. Of the 138 valves tested for leakage, 31 valves had medium to very large leaks. Of these 31 leaking valves identified, 30 were repaired or replaced.

  17. Photometric and spectroscopic variability of the FUor star V582 Aurigae

    E-Print Network [OSTI]

    Semkov, E H; Munari, U; Dennefeld, M; Mito, H; Dimitrov, D P; Ibryamov, S; Stoyanov, K A

    2013-01-01

    We carried out BVRI CCD photometric observations in the field of V582 Aur from 2009 August to 2013 February. We acquired high-, medium-, and low-resolution spectroscopy of V582 Aur during this period. To study the pre-outburst variability of the target and construct its historical light curve, we searched for archival observations in photographic plate collections. Both CCD and photographic observations were analyzed using a sequence of 14 stars in the field of V582 Aur calibrated in BVRI. The pre-outburst photographic observations of V582 Aur show low-amplitude light variations typical of T Tauri stars. Archival photographic observations indicate that the increase in brightness began in late 1984 or early 1985 and the star reached the maximum level of brightness at 1986 January. The spectral type of V582 Aur can be defined as G0I with strong P Cyg profiles of H alpha and Na I D lines, which are typical of FU Orionis objects. Our BVRI photometric observations show large amplitude variations V~2.8 mag. during ...

  18. Field observations of soil moisture variability across scales

    E-Print Network [OSTI]

    Famiglietti, James S; Ryu, Dongryeol; Berg, Aaron A; Rodell, Matthew; Jackson, Thomas J

    2008-01-01

    extent scales and wet- ness conditions. The more than 36,000deviation, CV, and skew- ness versus mean moisture contentstandard deviation and skew- ness versus mean soil moisture,

  19. 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.

  20. Efficiency of autonomous soft nano-machines at maximum power

    E-Print Network [OSTI]

    Udo Seifert

    2010-11-11

    We consider nano-sized artificial or biological machines working in steady state enforced by imposing non-equilibrium concentrations of solutes or by applying external forces, torques or electric fields. For unicyclic and strongly coupled multicyclic machines, efficiency at maximum power is not bounded by the linear response value 1/2. For strong driving, it can even approach the thermodynamic limit 1. Quite generally, such machines fall in three different classes characterized, respectively, as "strong and efficient", "strong and inefficient", and "balanced". For weakly coupled multicyclic machines, efficiency at maximum power has lost any universality even in the linear response regime.

  1. 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.

  2. 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.

  3. Variable frequency photonic crystals

    E-Print Network [OSTI]

    Wu, Xiang-Yao; Liu, Xiao-Jing; Yang, Jing-Hai; Li, Hong; Chen, Wan-Jin

    2015-01-01

    In this paper, we have firstly proposed a new one-dimensional variable frequency photonic crystals (VFPCs), and calculated the transmissivity and the electronic field distribution of VFPCs with and without defect layer, and considered the effect of defect layer and variable frequency function on the transmissivity and the electronic field distribution. We have obtained some new characteristics for the VFPCs, which should be help to design a new type optical devices.

  4. Partial Observers

    E-Print Network [OSTI]

    Thomas Marlow

    2006-10-20

    We attempt to dissolve the measurement problem using an anthropic principle which allows us to invoke rational observers. We argue that the key feature of such observers is that they are rational (we need not care whether they are `classical' or `macroscopic' for example) and thus, since quantum theory can be expressed as a rational theory of probabilistic inference, the measurement problem is not a problem.

  5. Distributed Computation of Maximum Lifetime Spanning Subgraphs in Sensor Networks

    E-Print Network [OSTI]

    ­ Helsinki University of Technology, P.O. Box 5400, FI-02015 TKK, Finland Harri.Haanpaa@tkk.fi, Andre levels to the battery-operated nodes so that under a uniform traffic load the net- work remains connected for a maximum length of time [2]. We consider the case where the nodes are non-mobile and the power levels, once

  6. Maximization of Recursive Utilities: A Dynamic Maximum Principle Approach

    E-Print Network [OSTI]

    Di Girolami, Cristina

    Maximization of Recursive Utilities: A Dynamic Maximum Principle Approach Wahid FAIDI LAMSIN, ENIT for a class of robust utility function introduced in Bordigoni, Matoussi et Schweizer (2005). Our method-investment strategy which is characterized as the unique solution of a forward-backward system. Key words : Utility

  7. The Evolution of Maximum Body Size of Terrestrial Mammals

    E-Print Network [OSTI]

    Brown, James H.

    The Evolution of Maximum Body Size of Terrestrial Mammals Felisa A. Smith,1 * Alison G. Boyer,2 the primary driver for the evolution of giant mammals was diversification to fill ecological niches extracted from the Paleobiology Database (12), using the range- through option for each interval of time. We

  8. Multiresolution Maximum Intensity Volume Rendering by Morphological Pyramids

    E-Print Network [OSTI]

    Roerdink, Jos B.T.M.

    to wavelet splatting, the main differences being that (i) linear summation of voxel values is replaced by maximum computation, and (ii) linear wavelet filters are replaced by (nonlinear) morphological filters. 1 on wavelets [4, 12, 18]. Recent methods for X-ray rendering include wavelet splatting [7, 8], which extends

  9. Multiresolution Maximum Intensity Volume Rendering by Morphological Adjunction Pyramids

    E-Print Network [OSTI]

    Roerdink, Jos B.T.M.

    to wavelet splatting, the main differences being that (i) linear summation of voxel values is replaced by maximum computation, and (ii) linear wavelet filters are replaced by (nonlinear) morphological filters wavelet splatting [11,12], which extends splatting [27] by using wavelets as reconstruction filters

  10. Maximum likelihood estimation of the equity Efstathios Avdis

    E-Print Network [OSTI]

    Kahana, Michael J.

    premium is usually estimated by taking the sample mean of stock returns and subtracting a measure the expected return on the aggregate stock market less the government bill rate, is of central importance an alternative esti- mator, based on maximum likelihood, that takes into account informa- tion contained

  11. "Maximum recycling of Material and Energy, Minimum of Landfilling"

    E-Print Network [OSTI]

    Columbia University

    lack of Waste-to-Energy capacity. #12;9 Austria As Germany, but Ban in force already in 2002. Landfill1 "Maximum recycling of Material and Energy, Minimum of Landfilling" "A Sustainable Solution" Håkan in "Recycling". "Waste-to-Energy" is now defined as Recycling, when energy efficiency is > 0,65 Prevention Reuse

  12. Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint

    E-Print Network [OSTI]

    Greenberg, Albert

    Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint Zhe Wang Electrical--In this paper, we develop efficient algorithm to obtain the optimal energy schedule for fading channel with energy harvesting. We assume that the side information of both the channel states and energy harvesting

  13. The Entropy of the Universe and the Maximum Entropy Production

    E-Print Network [OSTI]

    Lineweaver, Charles H.

    Chapter 22 The Entropy of the Universe and the Maximum Entropy Production Principle Charles H. Lineweaver Abstract If the universe had been born in a high entropy, equilibrium state, there would be no stars, no planets and no life. Thus, the initial low entropy of the universe is the fundamental reason

  14. What is a Hurricane? Tropical system with maximum sustained

    E-Print Network [OSTI]

    Meyers, Steven D.

    Hurricane 101 #12;What is a Hurricane? · Tropical system with maximum sustained surface wind of 74 mph or greater. A hurricane is the worst and the strongest of all tropical systems. · Also known as a tropical cyclone. #12;Hurricanes in Florida · 1851-2004 Florida's Hurricane Total: 110 Southwest Florida

  15. CX Lyrae 2008 Observing Campaign

    E-Print Network [OSTI]

    de Ponthiere, Pierre; Hambsch, Franz-Josef

    2012-01-01

    The Blazhko effect in CX Lyr has been reported for the first time by Le Borgne et al. (2007). The authors have pointed out that the Blazhko period was not evaluated accurately due to dataset scarcity. The possible period values announced were 128 or 227 days. A newly conducted four-month observing campaign in 2008 (fifty-nine observation nights) has provided fourteen times of maximum. From a period analysis of measured times of maximum, a Blazhko period of 62 +/- 2 days can be suggested. However, the present dataset is still not densely sampled enough to exclude that the measured period is still a modulation of the real Blazhko period. Indeed the shape of the (O-C) curve does not repeat itself exactly during the campaign duration.

  16. Total Solar Irradiance Variability and the Solar Activity Cycle

    E-Print Network [OSTI]

    Probhas Raychaudhuri

    2006-05-06

    It is suggested that the solar variability is due to the perturbed nature of the solar core and this variability is provided by the variability of the solar neutrino flux from the solar neutrino detectors i.e., Homestake, Superkamiokande, SAGE and GALLEX-GNO. The solar neutrino flux in the standard solar model (SSM) was calculated on the assumption of L_nu (neutrino luminosity) = L_gamma (optical luminosity) which implies that if there is a change in optical luminosity then solar neutrino flux data will also be changed. An internal dynamo due to the cyclic variation of nuclear energy generation inside the core of the sun is responsible for the solar activity cycle was suggested and thus the internal magnetic field is also variable. Again the changes in the nuclear energy generation induce structural changes that result in variations of the global solar parameters i.e., luminosity, radius and temperatures etc. From the analysis of total solar irradiance (TSI) data during the year from 1970 to 2003 we have found five phases within the solar activity cycle. The first phase (I) starts before two years from the sunspot minimum. The second phase (II) starts at the time of sunspot minimum and phase (III) starts before 2/3 years from sunspot maximum whereas phase (IV) starts at sunspot maximum and fifth phase (V) starts at after 2-3 years from sunspot maximum.

  17. Long-term spectroscopic monitoring of the Luminous Blue Variable HD160529

    E-Print Network [OSTI]

    Otmar Stahl; Thomas Gaeng; Chris Sterken; Andreas Kaufer; Thomas Rivinius; Thomas Szeifert; Bernhard Wolf

    2002-12-20

    We have spectroscopically monitored the galactic Luminous Blue Variable HD 160529 and obtained an extensive high-resolution data set that covers the years 1991 to 2002. During this period, the star evolved from an extended photometric minimum phase towards a new visual maximum. In several observing seasons, we covered up to four months with almost daily spectra. Our spectra typically cover most of the visual spectral range with a high spectral resolution (about 20,000 or more). This allows us to investigate the variability in many lines and on many time scales from days to years. We find a correlation between the photospheric HeI lines and the brightness of the star, both on a time scale of months and on a time scale of years. The short-term variations are smaller and do not follow the long-term trend, strongly suggesting different physical mechanisms. Metal lines also show both short-term and long-term variations in strength and also a long-term trend in radial velocity. Most of the line-profile variations can be attributed to changing strengths of lines. Propagating features in the line profiles are rarely observed. We find that the mass-loss rate of HD 160529 is almost independent of temperature, i.e. visual brightness.

  18. 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.

  19. Variable Refrigerant Flow HVAC 

    E-Print Network [OSTI]

    Jones, S.

    2013-01-01

    Variable refrigerant flow technology HVAC CATEE 2013 San Antonio, TX ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16-18 What is the acronym VRF? ? Variable Refrigerant Flow Operates like a... heat pump utilizing VFD Inverter Compressors and LEV’s Unlike conventional commercial and residential HVAC systems in the USA The predominate method of cooling and heating in the world ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency...

  20. Maximum Entropy Principle and the Higgs Boson Mass

    E-Print Network [OSTI]

    Alves, Alexandre; da Silva, Roberto

    2014-01-01

    A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.

  1. Maximum Entropy Principle and the Higgs Boson Mass

    E-Print Network [OSTI]

    Alexandre Alves; Alex G. Dias; Roberto da Silva

    2014-11-18

    A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.

  2. The Prediction of the Maximum Modes of Decay of Mesons

    E-Print Network [OSTI]

    Ramanna, R

    1999-01-01

    In an earlier work, several properties of fundamental particles were brought together by a simple equation based on continuity and discreteness. It is shown here, that the maximum modes of decay of all fundamental particles can also be predicted without any arbitrary parameters. The method used is to break up the mean lifetimes of particles to obtain the maximum modes of decay. This is done by using a binary expansion of $\\hbar/MT$ where M is the mass of the particle and T is the mean lifetime. The agreements between that obtained from theory and experiment are remarkable. The ordering of the flavours plays an important part in understanding the reasons for this agreement. It is shown that the Zeno effect in Quantum mechanics is connected with use of the binary series.

  3. The Prediction of the Maximum Modes of Decay of Mesons

    E-Print Network [OSTI]

    Raja Ramanna

    1999-04-27

    In an earlier work, several properties of fundamental particles were brought together by a simple equation based on continuity and discreteness. It is shown here, that the maximum modes of decay of all fundamental particles can also be predicted without any arbitrary parameters. The method used is to break up the mean lifetimes of particles to obtain the maximum modes of decay. This is done by using a binary expansion of $\\hbar/MT$ where M is the mass of the particle and T is the mean lifetime. The agreements between that obtained from theory and experiment are remarkable. The ordering of the flavours plays an important part in understanding the reasons for this agreement. It is shown that the Zeno effect in Quantum mechanics is connected with use of the binary series.

  4. 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.

  5. 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.

  6. PNNL: A Supervised Maximum Entropy Approach to Word Sense Disambiguation

    SciTech Connect (OSTI)

    Tratz, Stephen C.; Sanfilippo, Antonio P.; Gregory, Michelle L.; Chappell, Alan R.; Posse, Christian; Whitney, Paul D.

    2007-06-23

    In this paper, we described the PNNL Word Sense Disambiguation system as applied to the English All-Word task in Se-mEval 2007. We use a supervised learning approach, employing a large number of features and using Information Gain for dimension reduction. Our Maximum Entropy approach combined with a rich set of features produced results that are significantly better than baseline and are the highest F-score for the fined-grained English All-Words subtask.

  7. 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.

  8. Maximum Power Transfer Tracking for a Photovoltaic-Supercapacitor Energy System

    E-Print Network [OSTI]

    Pedram, Massoud

    Maximum Power Transfer Tracking for a Photovoltaic-Supercapacitor Energy System Younghyun KimPconverter Ppv Pcharge Varying Pleak PV array Supercapacitor Figure 1: Photovoltaic-supercapacitor energy system Keywords Maximum power transfer tracking, Photovoltaic, Supercapacitor 1. INTRODUCTION Maximum energy

  9. Phylogeography of the Variable Dwarf-Kingfisher Ceyx lepidus (Aves: Alcedinidae) Inferred from Mitochondrial and Nuclear DNA Sequences

    E-Print Network [OSTI]

    Anderson, Michael J.; Oliveros, Carl Hirang; Filardi, Christopher E.; Moyle, Robert G.

    2013-01-01

    We reconstructed the phylogeographic relationships of the Variable Dwarf-Kingfisher (Ceyx lepidus) using DNA sequence data. Maximum likelihood and Bayesian analysis methods were used to reconstruct trees from a multilocus ...

  10. RXTE Observations of an Outburst of Recurrent X-ray Nova GS 1354-644

    E-Print Network [OSTI]

    Mikhail G. Revnivtsev; Konstantin N. Borozdin; William C. Priedhorsky; Alexey Vikhlinin

    1999-10-13

    We present the results of Rossi X-ray Timing Explorer observations of GS 1354-644 during a modest outburst in 1997-1998. The source is one of a handful of black hole X-ray transients that are confirmed to be recurrent in X-rays. A 1987 outburst of the same source observed by Ginga was much brighter, and showed a high/soft spectral state. In contrast the 1997-1998 outburst showed a low/hard spectral state. Both states are typical for black hole binaries. The RXTE All Sky Monitor observed an outburst duration of 150 to 200 days. PCA and HEXTE observations covered ~70 days near the maximum of the light curve and during the flux decline. Throughout the observations, the spectrum can be approximated by Compton upscattering of soft photons by energetic electrons. The hot electron cloud has a temperature kT ~30 keV and optical depth tau~4--5. To fit the data well an additional iron fluorescent line and reflection component are required, which indicates the presence of optically thick cool material, most probably in the outer part of the accretion disk. Dramatic fast variability was observed, and has been analyzed in the context of a shot noise model. The spectrum appeared to be softest at the peaks of the shot-noise variability. The shape of the power spectrum was typical for black hole systems in a low/hard state. We note a qualitative difference in the shape of the dependence of fractional variability on energy, when we compare systems with black holes and with neutron stars. Since it is difficult to discriminate these systems on spectral grounds, at least in their low/hard states, this new difference might be important.

  11. Continuous Variable Quantum Information Processing

    E-Print Network [OSTI]

    Ulrik L. Andersen; Gerd Leuchs; Christine Silberhorn

    2010-08-20

    Observables of quantum systems can posses either a discrete or a continuous spectrum. For example, upon measurements of the photon number of a light state, discrete outcomes will result whereas measurements of the light's quadrature amplitudes result in continuous outcomes. If one uses the continuous degree of freedom of a quantum system either for encoding, processing or detecting information, one enters the field of continuous variable (CV) quantum information processing. In this paper we review the basic principles of CV quantum information processing with main focus on recent developments in the field. We will be addressing the three main stages of a quantum informational system; the preparation stage where quantum information is encoded into CVs of coherent states and single photon states, the processing stage where CV information is manipulated to carry out a specified protocol and a detection stage where CV information is measured using homodyne detection or photon counting.

  12. Microlensing induced absorption line variability

    E-Print Network [OSTI]

    Geraint F. Lewis; Rodrigo A. Ibata

    2002-12-02

    Gravitational microlensing has proven to be a powerful probe of both the structure at the heart of quasars and the mass function of compact objects in foreground lenses. This paper examines the potential of gravitational microlensing in probing the scale of structure in absorbing material within the lensing galaxy. We find that, in this high optical depth regime, significant variations in the equivalent width of absorption features can be induced, although the details of these are dependent upon the scale of structure of the absorbing material. The paper concludes with an examination of the absorption line variability observed in the gravitationally lensed quasar PKS1830-211, demonstrating how this may indicate the presence of small scale structure in the cold molecular gas present within the lensing galaxy.

  13. 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.

  14. Emerging local warming signals in observational data

    E-Print Network [OSTI]

    Mahlstein, Irina

    The global average temperature of the Earth has increased, but year-to-year variability in local climates impedes the identification of clear changes in observations and human experience. For a signal to become obvious in ...

  15. 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.

  16. 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.

  17. 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.

  18. Maximum likelihood method for cross-correlations with astrophysical sources

    SciTech Connect (OSTI)

    Jansson, Ronnie; Farrar, Glennys R, E-mail: rj486@nyu.edu, E-mail: gf25@nyu.edu [Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY 10003 (United States)

    2008-06-15

    We generalize the maximum likelihood-type method used to study cross-correlations between a catalog of candidate astrophysical sources and ultrahigh energy cosmic rays (UHECRs), to allow for differing source luminosities. The new method is applicable to any sparse dataset such as UHE gamma rays or astrophysical neutrinos. Performance of the original and generalized techniques is evaluated in simulations of various scenarios. Applying the new technique to data, we find an excess correlation of about nine events between HiRes UHECRs and known BLLacs, with a 6 Multiplication-Sign 10{sup -5} probability of such a correlation arising by chance.

  19. Maximum Likelihood Method for Cross Correlations with Astrophysical Sources

    E-Print Network [OSTI]

    Ronnie Jansson; Glennys R. Farrar

    2008-06-18

    We generalize the Maximum Likelihood-type method used to study cross correlations between a catalog of candidate astrophysical sources and Ultrahigh Energy Cosmic Rays (UHECRs), to allow for differing source luminosities. The new method is applicable to any sparse data set such as UHE gamma rays or astrophysical neutrinos. Performance of the original and generalized techniques is evaluated in simulations of various scenarios. Applying the new technique to data, we find an excess correlation of about 9 events between HiRes UHECRs and known BLLacs, with a 6*10^-5 probability of such a correlation arising by chance.

  20. Bacteria Total Maximum Daily Load Task Force Final Report 

    E-Print Network [OSTI]

    Jones, C. Allan; Wagner, Kevin; Di Giovanni, George; Hauck, Larry; Mott, Joanna; Rifai, Hanadi; Srinivasan, Raghavan; Ward, George; Wythe, Kathy

    2009-01-01

    stream_source_info TR-341 Bacteria TMDL Task Force Report Draft Four 6.4.07.pdf.txt stream_content_type text/plain stream_size 344770 Content-Encoding ISO-8859-1 stream_name TR-341 Bacteria TMDL Task Force Report Draft Four 6....4.07.pdf.txt Content-Type text/plain; charset=ISO-8859-1 TR-341 2009 Bacteria Total Maximum Daily Load Task Force Final Report By C. Allan Jones and Kevin Wagner, Texas Water Resources...

  1. Maximum Tension: with and without a cosmological constant

    E-Print Network [OSTI]

    Barrow, John D.; Gibbons, G. W.

    2014-12-04

    and the absence of any speed limit for information transmission. This unusual Newtonian behaviour has no general relativistic counterpart: two particles of mass M whose centres approach closer than d = 4GM=c2 will ?nd themselves inside a black hole horizon... , Ann. d Physik 11, 69 (1900); English translation in M. Planck, 1959, The Theory of Heat Radiation, transl. M. Masius, Dover, New York (1959). 11 Schiller C., 1997-2004, Maximum force a simple principle encompassing general relativity in C. Schiller...

  2. Better Nonlinear Models from Noisy Data: Attractors with Maximum Likelihood

    E-Print Network [OSTI]

    Patrick E. McSharry; Leonard A. Smith

    1999-11-30

    A new approach to nonlinear modelling is presented which, by incorporating the global behaviour of the model, lifts shortcomings of both least squares and total least squares parameter estimates. Although ubiquitous in practice, a least squares approach is fundamentally flawed in that it assumes independent, normally distributed (IND) forecast errors: nonlinear models will not yield IND errors even if the noise is IND. A new cost function is obtained via the maximum likelihood principle; superior results are illustrated both for small data sets and infinitely long data streams.

  3. The Maximum Value Method. (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)FeedbackProperties ofThe Maximum Value Method. Citation Details

  4. On the Impossibility of Covariant Nonlocal "hidden" Variables in Quantum Physics

    E-Print Network [OSTI]

    Nicolas Gisin

    2010-02-06

    Local variables can't describe the quantum correlations observed in tests of Bell inequalities. Likewise, we show that nonlocal variables can't describe quantum correlations in a relativistic time-order invariant way.

  5. Reduction of tropical land region precipitation variability via transpiration

    E-Print Network [OSTI]

    Lee, Jung-Eun

    Tropical rainforests are known to exhibit low intraseasonal precipitation variability compared with oceanic areas with similar mean precipitation in observations and models. In the present study, the potential role of ...

  6. Thermodynamics of Maximum Transition Entropy for Quantum Assemblies

    E-Print Network [OSTI]

    David M. Rogers

    2015-03-27

    This work presents a general unifying theoretical framework for quantum non-equilibrium systems. It is based on a re-statement of the dynamical problem as one of inferring the distribution of collision events that move a system toward thermal equilibrium from an arbitrary starting distribution. Using a form based on maximum entropy for this transition distribution leads to a statistical description of open quantum systems with strong parallels to the conventional, maximum-entropy, equilibrium thermostatics. A precise form of the second law of thermodynamics can be stated for this dynamics at every time-point in a trajectory. Numerical results are presented for low-dimensional systems interacting with cavity fields. The dynamics and stationary state are compared to a reference model of a weakly coupled oscillator plus cavity supersystem thermostatted by periodic partial measurements. Despite the absence of an explicit cavity in the present model of open quantum dynamics, both the relaxation rates and stationary state properties closely match the reference. Additionally, the time-course of energy exchange and entropy increase is given throughout an entire measurement process for a single spin system. The results show the process to be capable of initially absorbing heat when starting from a superposition state, but not from an isotropic distribution. Based on these results, it is argued that logical inference in the presence of environmental noise is sufficient to resolve the paradox of wavefunction collapse.

  7. 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.

  8. A review of instrumental variable estimators for Mendelian randomization

    E-Print Network [OSTI]

    Burgess, Stephen; Small, Dylan S.; Thompson, Simon G.

    2015-07-13

    .pdf.txt Content-Type text/plain; charset=UTF-8 A review of instrumental variable estimators for Mendelian randomization Stephen Burgess 1,? Dylan S. Small 2 Simon G. Thompson 1 1 Department of Public Health and Primary Care University of Cambridge, UK 2... as instrumental variables in observational data has been termed ‘Mendelian randomization’ [6, 7]. Many reviews exist on the use of instrumental variables, in particular on the as- sumptions necessary to be an instrumental variable [8, 9], assessing the validity...

  9. 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.

  10. Improved Maximum Entropy Analysis with an Extended Search Space

    E-Print Network [OSTI]

    Alexander Rothkopf

    2013-01-07

    The standard implementation of the Maximum Entropy Method (MEM) follows Bryan and deploys a Singular Value Decomposition (SVD) to limit the dimensionality of the underlying solution space apriori. Here we present arguments based on the shape of the SVD basis functions and numerical evidence from a mock data analysis, which show that the correct Bayesian solution is not in general recovered with this approach. As a remedy we propose to extend the search basis systematically, which will eventually recover the full solution space and the correct solution. In order to adequately approach problems where an exponentially damped kernel is used, we provide an open-source implementation, using the C/C++ language that utilizes high precision arithmetic adjustable at run-time. The LBFGS algorithm is included in the code in order to attack problems without the need to resort to a particular search space restriction.

  11. Efficiency at maximum power of a chemical engine

    E-Print Network [OSTI]

    Hooyberghs, Hans; Salazar, Alberto; Indekeu, Joseph O; Broeck, Christian Van den

    2013-01-01

    A cyclically operating chemical engine is considered that converts chemical energy into mechanical work. The working fluid is a gas of finite-sized spherical particles interacting through elastic hard collisions. For a generic transport law for particle uptake and release, the efficiency at maximum power $\\eta$ takes the form 1/2+c\\Delta \\mu + O(\\Delta \\mu^2), with 1/2 a universal constant and $\\Delta \\mu$ the chemical potential difference between the particle reservoirs. The linear coefficient c is zero for engines featuring a so-called left/right symmetry or particle fluxes that are antisymmetric in the applied chemical potential difference. Remarkably, the leading constant in $\\eta$ is non-universal with respect to an exceptional modification of the transport law. For a nonlinear transport model we obtain \\eta = 1/(\\theta +1), with \\theta >0 the power of $\\Delta \\mu$ in the transport equation

  12. Fracture Toughness and Maximum Stress in a Disordered Lattice System

    E-Print Network [OSTI]

    Chiyori Urabe; Shinji Takesue

    2008-12-29

    Fracture in a disordered lattice system is studied. In our system, particles are initially arranged on the triangular lattice and each nearest-neighbor pair is connected with a randomly chosen soft or hard Hookean spring. Every spring has the common threshold of stress at which it is cut. We make an initial crack and expand the system perpendicularly to the crack. We find that the maximum stress in the stress-strain curve is larger than those in the systems with soft or hard springs only (uniform systems). Energy required to advance fracture is also larger in some disordered systems, which indicates that the fracture toughness improves. The increase of the energy is caused by the following two factors. One is that the soft spring is able to hold larger energy than the hard one. The other is that the number of cut springs increases as the fracture surface becomes tortuous in disordered systems.

  13. 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.

  14. THE OPTICAL GRAVITATIONAL LENSING EXPERIMENT. THE CATALOG OF PERIODIC VARIABLE STARS IN THE GALACTIC BULGE. I. PERIODIC VARIABLES IN THE CENTER OF THE BAADE'S WINDOW.

    E-Print Network [OSTI]

    A. UDALSKI; M. KUBIAK; M. SZYMANSKI; J. KALUZNY; M. MATEO; W. KRZEMINSKI

    1995-01-09

    This paper is the first part of the Catalog of Periodic Variable Stars in the Galactic bulge. The Catalog is based on observations collected during the OGLE microlensing search. 213 periodic variable stars brighter than I=18 mag: 31 pulsating, 116 eclipsing and 66 miscellaneous type variables from the Baade's Window BWC field are presented. Periodic variable stars from remaining 20 fields will be presented in similar form in the next parts of the Catalog. The Catalog as well as observations of all periodic variable objects are available to astronomical community over the Internet network.

  15. A Fast Parallel Maximum Clique Algorithm for Large Sparse Graphs and Temporal Strong Components

    E-Print Network [OSTI]

    Rossi, Ryan A; Gebremedhin, Assefaw H; Patwary, Md Mostofa Ali

    2013-01-01

    We propose a fast, parallel, maximum clique algorithm for large, sparse graphs that is designed to exploit characteristics of social and information networks. We observe roughly linear runtime scaling over graphs between 1000 vertices and 100M vertices. In a test with a 1.8 billion-edge social network, the algorithm finds the largest clique in about 20 minutes. For social networks, in particular, we found that using the core number of a vertex in combination with a good heuristic clique finder efficiently removes the vast majority of the search space. In addition, we parallelize the exploration of the search tree. In the algorithm, processes immediately communicate changes to upper and lower bounds on the size of maximum clique, which occasionally results in a super-linear speedup because vertices with especially large search spaces can be pruned by other processes. We use this clique finder to investigate the size of the largest temporal strong components in dynamic networks, which requires finding the large...

  16. Spectrum of Controlling and Observing Complex Networks

    E-Print Network [OSTI]

    Yan, Gang; Barzel, Baruch; Slotine, Jean-Jacques; Liu, Yang-Yu; Barabasi, Albert-Laszlo

    2015-01-01

    Observing and controlling complex networks are of paramount interest for understanding complex physical, biological and technological systems. Recent studies have made important advances in identifying sensor or driver nodes, through which we can observe or control a complex system. Yet, the observation uncertainty induced by measurement noise and the energy cost required for control continue to be significant challenges in practical applications. Here we show that the control energy cost and the observation uncertainty vary widely in different directions of the state space. In particular, we find that if all nodes are directly driven, control is energetically feasible, as the maximum energy cost increases sublinearly with the system size. If, however, we aim to control a system by driving only a single node, control in some directions is energetically prohibitive, increasing exponentially with the system size. For the cases in between, the maximum energy decays exponentially if we increase the number of driv...

  17. Variability of QSOs with variable regions in broad absorption troughs from the Sloan Digital Sky Survey

    E-Print Network [OSTI]

    He, Zhi-Cheng; Jiang, Xiao-Lei; Ge, Xue

    2015-01-01

    The variability of broad absorption lines is investigated for a sample of 188 broad-absorption-line (BAL) quasars (QSOs) ($z > 1.7$) with at least two-epoch observations from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), covering a time-scale of about 0.001 -- 3 years in the rest frame. Considering only the longest time-scale between epochs for each QSO, 73 variable regions in the \\civ BAL troughs are detected for 43 BAL QSOs. The proportion of BAL QSOs showing variable regions increases with longer time-interval than about 1 year in the rest frame. The velocity width of variable regions is narrow compared to the BAL-trough outflow velocity. For 43 BAL QSOs with variable regions, it is found that there is a medium strong correlation between the variation of the continuum luminosity at 1500 \\AA\\ and the variation of the spectral index. With respect to the total 188 QSOs, larger proportion of BAL QSOs with variable regions appears bluer during their brighter phases, which implies that the origin of BA...

  18. 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

  19. 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.

  20. Predicting Whole Forest Structure, Primary Productivity, and Biomass Density From Maximum Tree Size and Resource Limitations

    E-Print Network [OSTI]

    Kempes, Christopher P; Dooris, William; West, Geoffrey B

    2015-01-01

    In the face of uncertain biological response to climate change and the many critiques concerning model complexity it is increasingly important to develop predictive mechanistic frameworks that capture the dominant features of ecological communities and their dependencies on environmental factors. This is particularly important for critical global processes such as biomass changes, carbon export, and biogenic climate feedback. Past efforts have successfully understood a broad spectrum of plant and community traits across a range of biological diversity and body size, including tree size distributions and maximum tree height, from mechanical, hydrodynamic, and resource constraints. Recently it was shown that global scaling relationships for net primary productivity are correlated with local meteorology and the overall biomass density within a forest. Along with previous efforts, this highlights the connection between widely observed allometric relationships and predictive ecology. An emerging goal of ecological...

  1. Maximum Entropy Analysis of the Spectral Functions in Lattice QCD

    E-Print Network [OSTI]

    M. Asakawa; T. Hatsuda; Y. Nakahara

    2001-02-26

    First principle calculation of the QCD spectral functions (SPFs) based on the lattice QCD simulations is reviewed. Special emphasis is placed on the Bayesian inference theory and the Maximum Entropy Method (MEM), which is a useful tool to extract SPFs from the imaginary-time correlation functions numerically obtained by the Monte Carlo method. Three important aspects of MEM are (i) it does not require a priori assumptions or parametrizations of SPFs, (ii) for given data, a unique solution is obtained if it exists, and (iii) the statistical significance of the solution can be quantitatively analyzed. The ability of MEM is explicitly demonstrated by using mock data as well as lattice QCD data. When applied to lattice data, MEM correctly reproduces the low-energy resonances and shows the existence of high-energy continuum in hadronic correlation functions. This opens up various possibilities for studying hadronic properties in QCD beyond the conventional way of analyzing the lattice data. Future problems to be studied by MEM in lattice QCD are also summarized.

  2. Improved Maximum Entropy Method with an Extended Search Space

    E-Print Network [OSTI]

    Alexander Rothkopf

    2012-08-25

    We report on an improvement to the implementation of the Maximum Entropy Method (MEM). It amounts to departing from the search space obtained through a singular value decomposition (SVD) of the Kernel. Based on the shape of the SVD basis functions we argue that the MEM spectrum for given $N_\\tau$ data-points $D(\\tau)$ and prior information $m(\\omega)$ does not in general lie in this $N_\\tau$ dimensional singular subspace. Systematically extending the search basis will eventually recover the full search space and the correct extremum. We illustrate this idea through a mock data analysis inspired by actual lattice spectra, to show where our improvement becomes essential for the success of the MEM. To remedy the shortcomings of Bryan's SVD prescription we propose to use the real Fourier basis, which consists of trigonometric functions. Not only does our approach lead to more stable numerical behavior, as the SVD is not required for the determination of the basis functions, but also the resolution of the MEM becomes independent from the position of the reconstructed peaks.

  3. 2011-07 "Maximum Utilization of WIPP by Increasing MDA G TRU...

    Office of Environmental Management (EM)

    7 "Maximum Utilization of WIPP by Increasing MDA G TRU Shipments" 2011-07 "Maximum Utilization of WIPP by Increasing MDA G TRU Shipments" The intent of this recommendation is to...

  4. Quantum-dot Carnot engine at maximum power Massimiliano Esposito

    E-Print Network [OSTI]

    Lindenberg, Katja

    of the CA model based on Carnot cycles performed in finite time, even though finding the optimal driving-state analysis has been clarified by identifying the Onsager coefficient for a finite-time Carnot cycle observed in a Carnot cycle based on a classical Brownian particle in a harmonic trap 8 . In this paper we

  5. Numerical Model Construction with Closed Observables

    E-Print Network [OSTI]

    Felix Dietrich; Gerta Köster; Hans-Joachim Bungartz

    2015-10-18

    Performing analysis, optimization and control using simulations of many-particle systems is computationally demanding when no macroscopic model for the dynamics of the variables of interest is available. In case observations on the macroscopic scale can only be produced via legacy simulator code or live experiments, finding a model for these macroscopic variables is challenging. In this paper, we employ time-lagged embedding theory to construct macroscopic numerical models from output data of a black box, such as a simulator or live experiments. Since the state space variables of the constructed, coarse model are dynamically closed and observable by an observation function, we call these variables closed observables. The approach is an online-offline procedure, as model construction from observation data is performed offline and the new model can then be used in an online phase, independent of the original. We illustrate the theoretical findings with numerical models constructed from time series of a two-dimensional ordinary differential equation system, and from the density evolution of a transport-diffusion system. Applicability is demonstrated in a real-world example, where passengers leave a train and the macroscopic model for the density flow onto the platform is constructed with our approach. If only the macroscopic variables are of interest, simulation runtimes with the numerical model are three orders of magnitude lower compared to simulations with the original fine scale model. We conclude with a brief discussion of possibilities of numerical model construction in systematic upscaling, network optimization and uncertainty quantification.

  6. Short-term irradiance variability: Preliminary estimation of station pair correlation as a function of distance

    E-Print Network [OSTI]

    Review Short-term irradiance variability: Preliminary estimation of station pair correlation the irradiance variability observed at two neighboring sites as a function of their distance of the considered time scale. Ó 2012 Elsevier Ltd. All rights reserved. Keywords: Irradiance; Variability; High

  7. Laboratory-Based Maximum Slip Rates in Earthquake Rupture Zones and Radiated Energy

    E-Print Network [OSTI]

    New Hampshire, University of

    Laboratory-Based Maximum Slip Rates in Earthquake Rupture Zones and Radiated Energy by A. McGarr, J. B. Fletcher, M. Boettcher, N. Beeler, and J. Boatwright Abstract Laboratory stick-slip friction and the maximum slip rate. From laboratory results, the maximum slip rate for any crustal earthquake, as well

  8. Envera Variable Compression Ratio Engine

    SciTech Connect (OSTI)

    Charles Mendler

    2011-03-15

    Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

  9. Estimation of the Diffusion Constant from Intermittent Trajectories with Variable Position Uncertainties

    E-Print Network [OSTI]

    Peter K. Relich; Mark J. Olah; Patrick J. Cutler; Keith A. Lidke

    2015-08-21

    The movement of a particle described by Brownian motion is quantified by a single parameter, $D$, the diffusion constant. The estimation of $D$ from a discrete sequence of noisy observations is a fundamental problem in biological single particle tracking experiments since it can report on the environment and/or the state of the particle itself via hydrodynamic radius. Here we present a method to estimate $D$ that takes into account several effects that occur in practice, that are important for correct estimation of $D$, and that have hitherto not been combined together for estimation of $D$. These effects are motion blur from finite integration time of the camera, intermittent trajectories, and time-dependent localization uncertainty. Our estimation procedure, a maximum likelihood estimation, follows directly from the likelihood expression for a discretely observed Brownian trajectory that explicitly includes these effects. The manuscript begins with the formulation of the likelihood expression and then presents three methods to find the exact solution. Each method has its own advantages in either computational robustness, theoretical insight, or the estimation of hidden variables. We then compare our estimator to previously published estimators using a squared log loss function to demonstrate the benefit of including these effects.

  10. Exploring Multiwavelength AGN Variability with Swift Archival Data

    E-Print Network [OSTI]

    Gelbord, Jonathan; Grupe, Dirk; Berk, Dan Vanden; Wu, Jian

    2015-01-01

    We are conducting an archival Swift program to measure multiwavelength variability in active galactic nuclei (AGN). This variability information will provide constraints on the geometry, physical conditions and processes of the structures around the central black holes that emit and reprocess the observed flux. Among our goals are: (1) to produce a catalog of type 1 AGN with time-resolved multi-wavelength data; (2) to characterize variability in the optical, UV and X-ay bands as well as changes in spectral slope; (3) to quantify the impact of variability on multi-wavelength properties; and (4) to measure correlated variability between bands. Our initial efforts have revealed a UVOT calibration issue that can cause a few percent of measured UV fluxes to be anomalously low, by up to 30%.

  11. A simple hidden variable experiment

    E-Print Network [OSTI]

    Arnold Neumaier

    2007-06-22

    An experiment is described which proves, using single photons only, that the standard hidden variables assumptions (commonly used to derive Bell inequalities) are inconsistent with quantum mechanics. The analysis is very simple and transparent. In particular, it demonstrates that a classical wave model for quantum mechanics is not ruled out by experiments demonstrating the violation of the traditional hidden variable assumptions.

  12. Control-Oriented Model of a Dual Equal Variable Cam Timing Spark Ignition Engine

    E-Print Network [OSTI]

    Grizzle, Jessy W.

    Control-Oriented Model of a Dual Equal Variable Cam Timing Spark Ignition Engine A. G of min- imizing exhaust emissions, providing increased fuel economy and satisfying driver perfor- mance that provides a tradeo among idle stability, fuel economy, and maximum torque performance. There are also

  13. Design of a variable reluctance asymmetric stepping millimotor

    SciTech Connect (OSTI)

    GARCIA,ERNEST J.; GREENWOOD,WILLIAM H.; OLIVER,ANDREW D.

    2000-06-01

    This paper reports on the design, simulation, and preliminary testing of a three phase variable reluctance stepping motor. This motor is pancake-shaped with an overall outside diameter of 8 mm and a height of 3 mm. The outside diameter of the rotor is 4.7 mm. The rotor and stators occupy 2 mm of the height with the remaining 1 mm reserved for a 6:1 planetary gear reductor. The rotor and stators were constructed of Hyperco 50 using conventional miniature machining. The reductor was assembled using copper and PMMA (polymethylmethacrylate) components that were constructed using the LIGA (Lithographic Galvanoformung Abformung) microfabrication process. The maximum measured stall torque of the motor without the reductor is 0.47mNm at 4W and the maximum speed is 2,400 rpm.

  14. Exact Radiation Model For Perfect Fluid Under Maximum Entropy Principle

    E-Print Network [OSTI]

    Farook Rahaman; Saibal Ray; Abdul Aziz; Sourav Roy Chowdhury; Debabrata Deb

    2015-04-12

    We find an expression for mass of spherically symmetric system solving Euler-Lagrangian equation by Homotopy Perturbation Method. With the help of this expression and the Einstien Field equations we obtain an interior solutions set. Thereafter we explain different aspects of the solution describing the system in connection to mass, density, pressures, energy, stability, mass-radius ratio, compactness factor and surface redshift. This analysis shows that all the physical properties, in connection to brown dwarf stars, are valid with the observed features except that of stability of the model which seems suffers from instability.

  15. Optical and Radio Variability of BL Lacertae

    E-Print Network [OSTI]

    Gaur, Haritma; Bachev, R; Strigachev, A; Semkov, E; Wiita, Paul J; Volvach, A E; Gu, Minfeng; Agarwal, A; Agudo, I; Aller, M F; Aller, H D; Kurtanidze, O M; Kurtanidze, S O; Lahteenmaki, A; Peneva, S; Nikolashvili, M G; Sigua, L A; Tornikoski, M; Volvach, L N

    2015-01-01

    We observed the prototype blazar, BL Lacertae, extensively in optical and radio bands during an active phase in the period 2010--2013 when the source showed several prominent outbursts. We searched for possible correlations and time lags between the optical and radio band flux variations using multifrequency data to learn about the mechanisms producing variability. During an active phase of BL Lacertae, we searched for possible correlations and time lags between multifrequency light curves of several optical and radio bands. We tried to estimate any possible variability timescales and inter-band lags in these bands. We performed optical observations in B, V, R and I bands from seven telescopes in Bulgaria, Georgia, Greece and India and obtained radio data at 36.8, 22.2, 14.5, 8 and 4.8 GHz frequencies from three telescopes in Ukraine, Finland and USA. Significant cross-correlations between optical and radio bands are found in our observations with a delay of cm-fluxes with respect to optical ones of ~250 days...

  16. Variable rate CELP speech coding using widely variable parameter updates 

    E-Print Network [OSTI]

    Moodie, Myron L.

    1995-01-01

    Code-excited, linear prediction (CELP) has become an accepted method for low bit rate, high quality coding of digital speech. The success of fixed rate CELP schemes has led to increased interest in variable rate techniques ...

  17. A computer program for maximum likelihood estimation of variance components 

    E-Print Network [OSTI]

    Hays, John Howard

    1967-01-01

    'OFX(XltP'tZtM ~ RUNK ~ TRSAV&DELTR)& D050Le I t M &&R I TEt 6t 10 &F &L ) b020LeltM IF(ABS(F(L )) ~ GT ~ ZMAM)GO TO I CON'T )NUE GQ TO 21 DO 3 Jeltel BK(J ~ ))eHt&F&J& DO 7 Ke2 ~ (ORDER KM)eK-I Xe'X 1+A (K ) t&H DO 2 Lel tM Z (L ) e Y (L & DO 6 Lel ~ M... and variation among determinations on the leaves. The statistical model used is (1) Xigh ~ + A + Bi) + eiyh i 1 a $ 1 b k+l s ~ o n where x ~& is the observation from the i. plant, leaf snd k determination. The Ai refers to plants effect with mean 0...

  18. Time-resolved photometry of cataclysmic variables

    E-Print Network [OSTI]

    C. Papadaki; H. M. J. Boffin; J. Cuypers; V. Stanishev; Z. Kraicheva; V. Genkov

    2003-12-18

    We present time-resolved photometry of two cataclysmic variables whose CCD photometric observations were obtained with the 1m telescope at the South African Astronomical Observatory in October 2002 and August 2003 and with the 1m telescope at Hoher List in Germany. Concerning MCT 2347-3144 we detect for the first time a period of 6.65h. For V1193 Ori the 3.96 h periodicity has for the first time been confirmed through time-resolved photometry.

  19. Using the Comoving Maximum of the Galaxy Power Spectrum to Measure Cosmological Curvature

    E-Print Network [OSTI]

    Tom Broadhurst; Andrew H. Jaffe

    1999-04-26

    The large-scale maximum at k~0.05 identified in the power-spectrum of galaxy fluctuations provides a co-moving scale for measuring cosmological curvature. In shallow 3D surveys the peak is broad, but appears to be well resolved in 1D, at ~130 Mpc (k=0.048), comprising evenly spaced peaks and troughs. Surprisingly similar behaviour is evident at z=3 in the distribution of Lyman-break galaxies, for which we find a 5 sigma excess of pairs separated by Delta z=0.22pm0.02, equivalent to 85Mpc for Omega=1, increasing to 170 Mpc for Omega=0, with a number density contrast of 30% averaged over 5 independent fields. The combination, 3.2\\Omega_m -\\Omega_{\\Lambda}=0.7, matches the local scale of 130 Mpc, i.e. Omega=0.2\\pm0.1 or Omega_{m}=0.4\\pm0.1 for the matter-dominated and flat models respectively, with an uncertainty given by the width of the excess correlation. The consistency here of the flat model with SNIa based claims is encouraging, but overshadowed by the high degree of coherence observed in 1D compared with conventional Gaussian models of structure formation. The appearance of this scale at high redshift and its local prominence in the distribution of Abell clusters lends support to claims that the high-z `spikes' represent young clusters. Finally we show that a spike in the primordial power spectrum of delta\\rho/\\rho=0.3 at k=0.05 has little effect on the CMB, except to exaggerate the first Doppler peak in flat matter-dominated models, consistent with recent observations. \\\\effect on the CMB, except to exaggerate the first Doppler peak in flat matter-dominated models, consistent with recent observations.

  20. VARIABILITY OF KD VALUES IN CEMENTITIOUS MATERIALS AND SEDIMENTS

    SciTech Connect (OSTI)

    Almond, P.; Kaplan, D.; Shine, E.

    2012-02-02

    Measured distribution coefficients (K{sub d} values) for environmental contaminants provide input data for performance assessments (PA) that evaluate physical and chemical phenomena for release of radionuclides from wasteforms, degradation of engineered components and subsequent transport of radionuclides through environmental media. Research efforts at SRNL to study the effects of formulation and curing variability on the physiochemical properties of the saltstone wasteform produced at the Saltstone Disposal Facility (SDF) are ongoing and provide information for the PA and Saltstone Operations. Furthermore, the range and distribution of plutonium K{sub d} values in soils is not known. Knowledge of these parameters is needed to provide guidance for stochastic modeling in the PA. Under the current SRS liquid waste processing system, supernate from F & H Tank Farm tanks is processed to remove actinides and fission products, resulting in a low-curie Decontaminated Salt Solution (DSS). At the Saltstone Production Facility (SPF), DSS is mixed with premix, comprised of blast furnace slag (BFS), Class F fly ash (FA), and portland cement (OPC) to form a grout mixture. The fresh grout is subsequently placed in SDF vaults where it cures through hydration reactions to produce saltstone, a hardened monolithic waste form. Variation in saltstone composition and cure conditions of grout can affect the saltstone's physiochemical properties. Variations in properties may originate from variables in DSS, premix, and water to premix ratio, grout mixing, placing, and curing conditions including time and temperature (Harbour et al. 2007; Harbour et al. 2009). There are no previous studies reported in the literature regarding the range and distribution of K{sub d} values in cementitious materials. Presently, the Savannah River Site (SRS) estimate ranges and distributions of K{sub d} values based on measurements of K{sub d} values made in sandy SRS sediments (Kaplan 2010). The actual cementitious material K{sub d} values and solubility values differ from the sandy sediments. The K{sub d} value range and distribution currently used in the PA are estimated to range between 0.25*K{sub d} and 1.75*K{sub d}, where the minimum and maximum values of the ranges reflect the 95% confidence level for the mean K{sub d} value (Kaplan 2010). The objective of the research with cementitious materials was to measure the range and distribution of a monovalent (Cs) and I{sup -} (anion), divalent (Sr), and trivalent (Eu) ions for a variety of laboratory-prepared saltstone surrogate samples to establish a K{sub d} range other than that which is presently used in the PA. It has been observed in laboratory samples that cure temperature profiles can affect properties such as heat of hydration, permeability, porosity, compressive strength, and set time (Harbour et al. 2009). The intent was to identify a range and distribution that could be used by stochastic modelers for the PA. Furthermore, the intent was to replace the arbitrarily selected distributions based on geological sandy sediments and to base it on actual cementitious materials. The scope of this study did not include understanding saltstone sorption mechanisms responsible for increasing or decreasing sorption. Similar to the work with cementitious materials, the purpose of the Pu sediment K{sub d} dataset was not to attempt to understand through statistics how to better understand Pu sorption to sediments or to lower Pu K{sub d} variance. The sediment Pu K{sub d} data is included in this study because it is a key risk driver for the PAs on the SRS, and there is presently no direct studies of Pu variability in SRS soils. Instead the distribution of Pu sediment K{sub d} values was assumed to be similar to other cations, as presented by Kaplan (2010).

  1. Analysis of MERCATOR data Part I: variable B stars

    E-Print Network [OSTI]

    P. De Cat; M. Briquet; C. Aerts; K. Goossens; S. Saesen; J. Cuypers; K. Yakut; R. Scuflaire; M. -A. Dupret; many observers

    2005-11-08

    We re-classified 31 variable B stars which were observed more than 50 times in the Geneva photometric system with the P7 photometer attached to the MERCATOR telescope (La Palma) during its first 3 years of scientific observations. HD89688 is a possible beta Cephei/slowly pulsating B star hybrid and the main mode of the COROT target HD180642 shows non-linear effects. The Maia candidates are re-classified as either ellipsoidal variables or spotted stars. Although the mode identification is still ongoing, all the well-identified modes so far have a degree l = 0, 1 or 2.

  2. Anisotropic Cosmological Model with Variable G and Lambda

    E-Print Network [OSTI]

    S. K. Tripathy; D. Behera; T. R. Routray

    2015-01-12

    Anisotropic Bianchi-III cosmological model is investigated with variable gravitational and cosmological constants in the framework of Einstein's general relativity. The shear scalar is considered to be proportional to the expansion scalar. The dynamics of the anisotropic universe with variable G and Lambda are discussed. Without assuming any specific forms for Lambda and the metric potentials, we have tried to extract the time variation of G and Lambda from the anisotropic model. The extracted G and Lambda are in conformity with the present day observation. Basing upon the observational limits, the behaviour and range of the effective equation of state parameter are discussed.

  3. Periodic Photometric Variability in the Becklin-Neugebauer Object

    E-Print Network [OSTI]

    Lynne A. Hillenbrand; John M. Carpenter; M. F. Skrutskie

    2000-10-24

    The Becklin-Neugebauer (BN) object in the Orion Nebula Cluster (ONC) is a well-studied optically invisible, infrared-bright young stellar object, thought to be an intermediate-mass protostar. We report here that BN exhibited nearly-sinusoidal periodic variability at the near-infrared H- and Ks-bands during a one month observing campaign in 2000 March/April. The period was 8.28 days and the peak-to-peak amplitude ~0.2 mag. Plausible mechanisms for producing the observed variability characteristics are explored.

  4. Anyonic statistics with continuous variables

    E-Print Network [OSTI]

    Jing Zhang; Changde Xie; Kunchi Peng; Peter van Loock

    2008-10-30

    We describe a continuous-variable scheme for simulating the Kitaev lattice model and for detecting statistics of abelian anyons. The corresponding quantum optical implementation is solely based upon Gaussian resource states and Gaussian operations, hence allowing for a highly efficient creation, manipulation, and detection of anyons. This approach extends our understanding of the control and application of anyons and it leads to the possibility for experimental proof-of-principle demonstrations of anyonic statistics using continuous-variable systems.

  5. Equations of State and Maximum Mass of Neutron Stars in Light of PSR J1614-2230

    E-Print Network [OSTI]

    Carlos Daniel Xu

    2012-10-31

    We shall examine various types of equations of state for neutron stars, which determine the structure of neutron stars. In particular, the relation between mass and radius of neutron stars is of primary consideration. By combining an equation of state (EOS) with the Tolmann-Oppenheimer-Volkoff structure equations, we can determine the theoretical maximum mass of a neutron star for a given equation of state. One question we seek to answer is whether quark matter can exist in the core of a neutron star. In light of the discovery of pulsar PSR J1614-2230, the mass of which is observed to be 1.97 solar masses, a valid equation of state must achieve a maximum mass that is greater than 2 solar masses. To try to solve this problem, we experiment with different sets of parameters for the quark matter to try to meet the lower limit 2-solar-mass criterion. It is found that certain parameters contribute significantly to the maximum mass of a neutron star.

  6. Effect of Variable Surrounding on Species Creation

    E-Print Network [OSTI]

    Aleksandra Nowicka; Artur Duda; Miroslaw R. Dudek

    2002-07-08

    We construct a model of speciation from evolution in an ecosystem consisting of a limited amount of energy recources. The species posses genetic information, which is inherited according to the rules of the Penna model of genetic evolution. The increase in number of the individuals of each species depends on the quality of their genotypes and the available energy resources. The decrease in number of the individuals results from the genetic death or reaching the maximum age by the individual. The amount of energy resources is represented by a solution of the differential logistic equation, where the growth rate of the amount of the energy resources has been modified to include the number of individuals from all species in the ecosystem under consideration. We observe that small evolutionary changes of the inherited genetic information lead to spontaneous bursts of the evolutionary activity when many new species may appear in a short period.

  7. Classification of Energy Flow Observables in Narrow Jets

    E-Print Network [OSTI]

    Guy Gur-Ari; Michele Papucci; Gilad Perez

    2011-01-14

    We present a classification of energy flow variables for highly collimated jets. Observables are constructed by taking moments of the energy flow and forming scalars of a suitable Lorentz subgroup. The jet shapes are naturally arranged in an expansion in both angular and energy resolution, allowing us to derive the natural observables for describing an N-particle jet. We classify the leading variables that characterize jets with up to 4 particles. We rediscover the familiar jet mass, angularities, and planar flow, which dominate the lowest order substructure variables. We also discover several new observables and we briefly discuss their physical interpretation.

  8. 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.

  9. GEO Secretariat Global Earth Observing System of

    E-Print Network [OSTI]

    and Epidemiology 3. Energy Management 4. Climate Variability & Change 5. Water Management 6. Weather Forecasting 7© GEO Secretariat Global Earth Observing System of Systems (GEOSS): Biodiversity, Ecosystems and GEO BON GEO Forest Monitoring Symposium 4 November 2008 Douglas M. Muchoney, Ph.D. U.S. Geological

  10. A PHOTOMETRICALLY AND MORPHOLOGICALLY VARIABLE INFRARED NEBULA IN L483

    SciTech Connect (OSTI)

    Connelley, Michael S. [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035 (United States); Hodapp, Klaus W. [University of Hawaii Institute for Astronomy, 640 N. Aohoku Pl., Hilo, HI 96720 (United States); Fuller, Gary A. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester, M13 9PL (United Kingdom)

    2009-03-15

    We present narrow and broad K-band observations of the Class 0/I source IRAS 18148-0440 that span 17 years. The infrared nebula associated with this protostar in the L483 dark cloud is both morphologically and photometrically variable on a timescale of only a few months. This nebula appears to be an infrared analog to other well known optically visible variable nebulae associated with young stars, such as Hubble's Variable Nebula. Along with Cepheus A, this is one of the first large variable nebulae to be found that is only visible in the infrared. The variability of this nebula is most likely due to changing illumination of the cloud rather than any motion of the structure in the nebula. Both morphological and photometric changes are observed on a timescale only a few times longer than the light crossing time of the nebula, suggesting very rapid intrinsic changes in the illumination of the nebula. Our narrowband observations also found that H{sub 2} knots are found nearly twice as far to the east of the source as to its west, and that H{sub 2} emission extends farther east of the source than the previously known CO outflow.

  11. Quasar Variability Measurements With SDSS Repeated Imaging and POSS Data

    E-Print Network [OSTI]

    Z Ivezic; R. H. Lupton; M. Juric; S. Anderson; P. B. Hall; G. T. Richards; C. M. Rockosi; D. E. Vanden Berk; E. L. Turner; G. R. Knapp; J. E. Gunn; D. Schlegel; M. A. Strauss; D. P. Schneider

    2004-04-26

    We analyze the properties of quasar variability using repeated SDSS imaging data in five UV-to-far red photometric bands, accurate to 0.02 mag, for 13,000 spectroscopically confirmed quasars. The observed time lags span the range from 3 hours to over 3 years, and constrain the quasar variability for rest-frame time lags of up to two years, and at rest-frame wavelengths from 1000 Ang. to 6000 Ang. We demonstrate that 66,000 SDSS measurements of magnitude differences can be described within the measurement noise by a simple function of only three free parameters. The addition of POSS data constrains the long-term behavior of quasar variability and provides evidence for a turn-over in the structure function. This turn-over indicates that the characteristic time scale for optical variability of quasars is of the order 1 year.

  12. A close hidden stellar companion to the SX Phe-type variable star DW Psc

    SciTech Connect (OSTI)

    Qian, S.-B.; Li, L.-J.; Wang, S.-M.; He, J.-J.; Zhou, X.; Jiang, L.-Q., E-mail: qsb@ynao.ac.cn [Yunnan Observatories, Chinese Academy of Sciences (CAS), P.O. Box 110, 650011 Kunming (China)

    2015-01-01

    DW Psc is a high-amplitude SX Phe-type variable with a period of pulsation of 0.05875 days. Using a few newly determined times of maximum light together with those collected from the literature, the changes in the observed-calculated (O-C) diagram are analyzed. It is discovered that the O-C curve of DW Psc shows a cyclic variation with a period of 6.08 years and a semi-amplitude of 0.0066 days. The periodic variation is analyzed for the light travel time effect, which is due to the presence of a stellar companion (M{sub 2}sini?0.45(±0.03) M{sub ?}). The two-component stars in the binary system are orbiting each other in an eccentric orbit (e ? 0.4) at an orbital separation of about 2.7(±0.3) AU. The detection of a close stellar companion to an SX Phe-type star supports the idea that SX Phe-type pulsating stars are blue stragglers that were formed from the merging of close binaries. The stellar companion has played an important role in the merging of the original binary by removing angular momentum from the central binary during early dynamical interaction or/and late dynamical evolution. After the more massive component in DW Psc evolves into a red giant, the cool close companion should help to remove the giant envelope via possible critical Roche-lobe overflow, and the system may be a progenitor of a cataclysmic variable. The detection of a close stellar companion to DW Psc makes it a very interesting system to study in the future.

  13. Temporal Variability of Fair-Weather Cumulus Statistics at the ACRF SGP Site

    SciTech Connect (OSTI)

    Berg, Larry K.; Kassianov, Evgueni I.

    2008-07-01

    Continental fair-weather cumuli exhibit significant diurnal, day-to-day, and year-to-year variability. This study describes the climatology of cloud macroscale properties, including the cloud-base height, cloud-top height, cloud thickness, and cloud chord length over the U.S. Department of Energy¹s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ARCF) Southern Great Plains (SGP) site. The diurnal cycle of cloud fraction, cloud-base height, and cloud-thickness were well defined. The cloud fraction reached its maximum value near 14:00 CST. The average cloud-base height increased throughout the day, while the average cloud thickness decreased with time. In contrast to the other cloud properties, the average cloud-chord length remained nearly constant throughout the day. The sensitivity of the cloud properties to the year-to-year variability and to changes in low-level moisture were compared. The cloud-base height was found to be sensitive to both the year and the low-level moisture, the cloud thickness was much more sensitive to the year then to the low-level moisture, and the cloud fraction and cloud chord length were more sensitive to the low-level moisture than to the year. Distributions of the cloud-chord length over the ARCF SGP site were computed and were well fit by an exponential distribution. The contribution of clouds of each cloud-chord length to the total cloud fraction was computed, and it was found the clouds with a chord length of about 1 km contributed the most to the observed cloud fraction.

  14. Ultraviolet and Multiwavelength Variability of the Blazar 3C 279 Evidence for Thermal Emission

    E-Print Network [OSTI]

    Pian, E; Maraschi, L; Madejski, G M; McHardy, I M; Koratkar, A P; Treves, A; Chiappetti, L; Grandi, P; Hartman, R C; Kubo, H; Leach, C M; Pesce, J E; Imhoff, C; Thompson, R; Wehrle, A E

    1999-01-01

    The gamma-ray blazar 3C 279 was monitored on a nearly daily basis with IUE, ROSAT and EGRET for three weeks between December 1992 and January 1993. During this period, the blazar was at a historical minimum at all wavelengths. Here we present the UV data obtained during the above multiwavelength campaign. A maximum UV variation of ~50% is detected, while during the same period the X-ray flux varied by no more than 13%. At the lowest UV flux level the average spectrum in the 1230-2700 A interval is unusually flat for this object (~1). The flattening could represent the lowest energy tail of the inverse Compton component responsible for the X-ray emission, or could be due to the presence of a thermal component at ~20000 K possibly associated with an accretion disk. The presence of an accretion disk in this blazar object, likely observable only in very low states and otherwise hidden by the beamed, variable synchrotron component, would be consistent with the scenario in which the seed photons for the inverse Com...

  15. Tsallis distribution as a standard maximum entropy solution with `tail' constraint

    E-Print Network [OSTI]

    Bercher, Jean-François

    Tsallis distribution as a standard maximum entropy solution with `tail' constraint J.-F. Bercher 1 that Tsallis' distributions can be derived from the standard (Shannon) maximum entropy setting, by incorporating a con- straint on the divergence between the distribution and another distribution imagined as its

  16. MAXIMUM POWER ESTIMATION OF LITHIUM-ION BATTERIES ACCOUNTING FOR THERMAL AND ELECTRICAL CONSTRAINTS

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    MAXIMUM POWER ESTIMATION OF LITHIUM-ION BATTERIES ACCOUNTING FOR THERMAL AND ELECTRICAL CONSTRAINTS on the maximum deliverable power is essential to protect lithium-ion batteries from over- charge Terminal voltage Voc Open circuit voltage of a battery 1 INTRODUCTION Lithium-ion batteries have been used

  17. Maximum Power Transfer Tracking in a Solar USB Charger for Smartphones

    E-Print Network [OSTI]

    Pedram, Massoud

    Maximum Power Transfer Tracking in a Solar USB Charger for Smartphones Abstract--Battery life of commercial chargers using solar power have been developed. They focus on correct functionality, but system chargers do not perform the maximum power point tracking [2], [3] of the solar panel. We exclude

  18. Maximum Weight Matching Dispatching Scheme in Buffered Clos-Network Packet Switches

    E-Print Network [OSTI]

    Chao, Jonathan

    Maximum Weight Matching Dispatching Scheme in Buffered Clos-Network Packet Switches Roberto Rojas of Clos-network switches make them an alternative to single-stages switches for implementing large- size packet switches. This paper introduces a cell dispatching scheme, called maximum weight matching

  19. Analysis and Optimization of Maximum Power Point Tracking Algorithms in the Presence of

    E-Print Network [OSTI]

    Odam, Kofi

    characteristic. This perturbation reduces the power obtained from the solar panel because the panel is no longerAnalysis and Optimization of Maximum Power Point Tracking Algorithms in the Presence of Noise maximum power point tracking (MPPT) algorithms for photovoltaic systems. Noise is an essential

  20. LANGMUIR WAVE ACTIVITY: COMPARING THE ULYSSES SOLAR MINIMUM AND SOLAR MAXIMUM ORBITS

    E-Print Network [OSTI]

    California at Berkeley, University of

    ). The top three panels correspond to the southern segment of the solar minimum orbit; repeated passesLANGMUIR WAVE ACTIVITY: COMPARING THE ULYSSES SOLAR MINIMUM AND SOLAR MAXIMUM ORBITS R. J at the electron plasma frequency) during the solar minimum and solar maximum orbits of Ulysses. At high latitudes

  1. Variable focal length deformable mirror

    SciTech Connect (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.

  2. Analyticity, Convergence and Convergence Rate of Recursive Maximum Likelihood Estimation in Hidden Markov Models

    E-Print Network [OSTI]

    Tadi?, Vladislav B

    2009-01-01

    This paper considers the asymptotic properties of the recursive maximum likelihood estimation in hidden Markov models. The paper is focused on the asymptotic behavior of the log-likelihood function and on the point-convergence and convergence rate of the recursive maximum likelihood estimator. Using the principle of analytical continuation, the analyticity of the asymptotic log-likelihood function is shown for analytically parameterized hidden Markov models. Relying on this fact and some results from differential geometry (Lojasiewicz inequality), the almost sure point-convergence of the recursive maximum likelihood algorithm is demonstrated, and relatively tight bounds on the convergence rate are derived. As opposed to the existing result on the asymptotic behavior of maximum likelihood estimation in hidden Markov models, the results of this paper are obtained without assuming that the log-likelihood function has an isolated maximum at which the Hessian is strictly negative definite.

  3. Reduction of tropical land region precipitation variability via transpiration

    E-Print Network [OSTI]

    Gentine, Pierre

    plants through open stomata: this process (transpiration) cools the plant and facilitates transportReduction of tropical land region precipitation variability via transpiration Jung-Eun Lee,1 in observations and models. In the present study, the potential role of transpiration for this difference

  4. 68 CEREAL CHEMISTRY Variability in Starch Acetylation Efficiency

    E-Print Network [OSTI]

    68 CEREAL CHEMISTRY Variability in Starch Acetylation Efficiency from Commercial Waxy Corn Hybrids procedure. To evaluate reaction efficiency, reaction rate, acetyl content, pH, and amount of NaOH used were acetylation protocol, reaction efficiencies were observed at 47­73%. Reaction efficiencies were significantly

  5. The hard X-ray emission of the luminous infrared galaxy NGC 6240 as observed by NuSTAR

    E-Print Network [OSTI]

    Puccetti, S; Bauer, F E; Brandt, W N; Fiore, F; Harrison, F A; Luo, B; Stern, D; Urry, C M; Alexander, D M; Annuar, A; Arévalo, P; Balokovi?, M; Boggs, S E; Brightman, M; Christensen, F E; Craig, W W; Gandhi, P; Hailey, C J; Koss, M J; La Massa, S; Marinucci, A; Ricci, C; Walton, D J; Zappacosta, L; Zhang, W

    2015-01-01

    We present a broad-band (~0.3-70 keV) spectral and temporal analysis of NuSTAR observations of the luminous infrared galaxy NGC 6240, combined with archival Chandra, XMM-Newton and BeppoSAX data. NGC 6240 is a galaxy in a relatively early merger state with two distinct nuclei separated by ~1."5. Previous Chandra observations have resolved the two nuclei, showing that they are both active and obscured by Compton-thick material. Although they cannot be resolved by NuSTAR, thanks to the unprecedented quality of the NuSTAR data at energies >10 keV, we clearly detect, for the first time, both the primary and the reflection continuum components. The NuSTAR hard X-ray spectrum is dominated by the primary continuum piercing through an absorbing column density which is mildly optically thick to Compton scattering (tau ~ 1.2, N_H ~ 1.5 x 10^(24) cm^-2). We detect moderate hard X-ray (> 10 keV) flux variability up to 20% on short (15-20 ksec) timescales. The amplitude of the variability is maximum at ~30 keV and is like...

  6. 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).

  7. A review of Hurricane Variability

    E-Print Network [OSTI]

    Nadiga, Balasubramanya T. "Balu"

    A review of Hurricane Variability Balu Nadiga, COSIM, LANL, Jun 2006 #12;#12;Key Sources · Kerry Emanuel · Webster 2005 · Elsner 1996 · NASA, NOAA, NCAR · Others #12;Hurricanes, Typhoons, Tropical (because rotation important) #12;Hurricanes: A few Comments · Acts as a heat engine, but with crucial fluid

  8. Phenotypic variability: underlying mechanisms and

    E-Print Network [OSTI]

    Mencuccini, Maurizio

    constraints on growth allocation between tree parts, which affects both primary production (through allocation to transpiring foliage) and net ecosystem production (through allocation to short- lived, easily decomposed fine is reflected in the huge variability in tree form and function across scales. It has been suggested

  9. 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.

  10. An examination of internally generated variability in long climate simulations

    SciTech Connect (OSTI)

    Schneider, E.K.; Kinter, J.L. III [Inst. of Global Environment and Society, Calverton, MD (United States)

    1994-09-01

    General circulation model experiments designed to estimate the magnitude and structure of internally generated variability and to help understand the mechanisms underlying this variability are described. The experiments consist of three multi-century integrations of a rhomboidal 15, 9 level, version of the Center for Ocean-Land-Atmosphere Studies atmospheric general circulation model: a run with fixed sea surface temperatures and equinox solar radiation, a run with seasonally varying climatological sea surface temperatures and seasonally varying solar forcing, and a run with seasonally varying solar forcing in which the state of the ocean is predicted by a 3{degree} by 3{degree}, 16 vertical level, nearly global domain version of the Geophysical Fluid Dynamics Laboratory Modular Ocean Model. No flux correction is used in the coupled model integration. Selected surface fields of the three runs are compared to each other as well as to the observed climate. Statistical properties of variability on interannual time scales are compared between the runs. Evidence is presented that climate time scale variability in the simulations is produced by random weather time scale forcing due to the integrating effect of elements of the system with long memories. The importance of ocean variability for land climate variability is demonstrated and attributed to both the memory effect and coupled atmosphere-ocean instability. 40 refs., 23 figs.

  11. The maximum efficiency of nano heat engines depends on more than temperature

    E-Print Network [OSTI]

    Mischa P. Woods; Nelly Ng; Stephanie Wehner

    2015-06-07

    Sadi Carnot's theorem regarding the maximum efficiency of heat engines is considered to be of fundamental importance in the theory of heat engines and thermodynamics. Here, we show that at the nano and quantum scale, this law needs to be revised in the sense that more information about the bath other than its temperature is required to decide whether maximum efficiency can be achieved. In particular, we derive new fundamental limitations of the efficiency of heat engines at the nano and quantum scale that show that the Carnot efficiency can only be achieved under special circumstances, and we derive a new maximum efficiency for others.

  12. Dark matter interacts with variable vacuum energy

    E-Print Network [OSTI]

    Iván E. Sánchez G

    2014-09-21

    We investigate a spatially flat Friedmann-Robertson-Walker (FRW) scenario with two interacting components, dark matter and variable vacuum energy (VVE) densities, plus two decoupled components, one is a baryon term while the other behaves as a radiation component. We consider a linear interaction in the derivative dark component density. We apply the $\\chi^2$ method to the observational Hubble data for constraining the cosmological parameters and analyze the amount of dark energy in the radiation era for the model. It turns out that our model fulfills the severe bound of $\\Omega_{x}(z\\simeq 1100)energy at early times, and fulfills the stringent bound $\\Omega_{x}(z\\simeq 10^{10})today.

  13. Primordial cosmic fluctuations for variable gravity

    E-Print Network [OSTI]

    Wetterich, C

    2015-01-01

    The observation of primordial cosmic fluctuations does not need a geometric horizon $H^{-1}$, which is exceeded temporarily by the wavelength of fluctuations. The primordial information can be protected against later thermal washout even if all relevant wavelengths remain smaller than $H^{-1}$. This is demonstrated by formulating the equations governing the cosmic fluctuations in a form that is manifestly invariant under conformal field transformations of the metric. Beyond the field equations this holds for the defining equation for the correlation function, as expressed by the inverse of the second functional derivative of the quantum effective action. An almost scale invariant spectrum does not need an expanding geometry. For a variable Planck mass it can even arise in flat Minkowski space.

  14. Optimal Control Theory for Continuous Variable Quantum Gates

    E-Print Network [OSTI]

    Rebing Wu; Raj Chakrabarti; Herschel Rabitz

    2007-08-16

    We apply the methodology of optimal control theory to the problem of implementing quantum gates in continuous variable systems with quadratic Hamiltonians. We demonstrate that it is possible to define a fidelity measure for continuous variable (CV) gate optimization that is devoid of traps, such that the search for optimal control fields using local algorithms will not be hindered. The optimal control of several quantum computing gates, as well as that of algorithms composed of these primitives, is investigated using several typical physical models and compared for discrete and continuous quantum systems. Numerical simulations indicate that the optimization of generic CV quantum gates is inherently more expensive than that of generic discrete variable quantum gates, and that the exact-time controllability of CV systems plays an important role in determining the maximum achievable gate fidelity. The resulting optimal control fields typically display more complicated Fourier spectra that suggest a richer variety of possible control mechanisms. Moreover, the ability to control interactions between qunits is important for delimiting the total control fluence. The comparative ability of current experimental protocols to implement such time-dependent controls may help determine which physical incarnations of CV quantum information processing will be the easiest to implement with optimal fidelity.

  15. Optical and X-ray Variability of Blazars

    E-Print Network [OSTI]

    Gupta, A C

    2015-01-01

    Here we report our recent results of variability studies in optical and X-ray bands of three blazars namely 3C 273, PKS 2155 - 304 and BL Lacertae with XMM-Newton. We found large amplitude optical to X-rays variability in 3C 273, and PKS 2155 - 304 on year time scale. In 3C 273, we noticed that synchrotron cooling and particle acceleration are at work at different epoch of observations. In PKS 2155 - 304, spectral energy distribution from optical to X-ray is fitted with LPPL (log parabolic + power law) model. In BL Lacertae, optical flux and degree of polarization were anti-correlated.

  16. Photometric and H$?$ observations of LSI+61303: detection of a $\\sim$26 day V and JHK band modulation

    E-Print Network [OSTI]

    J. M. Paredes; P. Marziani; J. Marti; J. Fabregat; M. J. Coe; C. Everall; F. Figueras; C. Jordi; A. J. Norton; T. Prince; V. Reglero; P. Roche; J. Torra; S. J. Unger; R. Zamanov

    1994-02-07

    We present new optical and infrared photometric observations and high resolution H$\\alpha$ spectra of the periodic radio star \\lsi. The optical photometric data set covers the time interval 1985-1993 and amounts to about a hundred nights. A period of $\\sim$26 days is found in the V band. The infrared data also present evidence for a similar periodicity, but with higher amplitude of variation (0\\rmag 2). The spectroscopic observations include 16 intermediate and high dispersion spectra of \\lsi\\ collected between January 1989 and February 1993. The H$\\alpha$ emission line profile and its variations are analyzed. Several emission line parameters -- among them the H$\\alpha$ EW and the width of the H$\\alpha$ red hump -- change strongly at or close to radio maximum, and may exhibit periodic variability. We also observe a significant change in the peak separation. The H$\\alpha$ profile of \\lsi\\ does not seem peculiar for a Be star. However, several of the observed variations of the H$\\alpha$ profile can probably be associated with the presence of the compact, secondary star.

  17. Nuclear-Powered Millisecond Pulsars and the Maximum Spin Frequency of Neutron Stars

    E-Print Network [OSTI]

    Deepto Chakrabarty; Edward H. Morgan; Michael P. Muno; Duncan K. Galloway; Rudy Wijnands; Michiel van der Klis; Craig B. Markwardt

    2003-07-01

    Millisecond pulsars are neutron stars (NSs) that are thought to have been spun-up by mass accretion from a stellar companion. It is unknown whether there is a natural brake for this process, or if it continues until the centrifugal breakup limit is reached at submillisecond periods. Many NSs that are accreting from a companion exhibit thermonuclear X-ray bursts that last tens of seconds, caused by unstable nuclear burning on their surfaces. Millisecond brightness oscillations during bursts from ten NSs (as distinct from other rapid X-ray variability that is also observed) are thought to measure the stellar spin, but direct proof of a rotational origin has been lacking. Here, we report the detection of burst oscillations at the known spin frequency of an accreting millisecond pulsar, and we show that these oscillations always have the same rotational phase. This firmly establishes burst oscillations as nuclear-powered pulsations tracing the spin of accreting NSs, corroborating earlier evidence. The distribution of spin frequencies of the 11 nuclear-powered pulsars cuts off well below the breakup frequency for most NS models, supporting theoretical predictions that gravitational radiation losses can limit accretion torques in spinning up millisecond pulsars.

  18. Nuclear-Powered Millisecond Pulsars and the Maximum Spin Frequency of Neutron Stars

    E-Print Network [OSTI]

    Chakraborty, D; Muno, M P; Galloway, D K; Wijnands, R; Van der Klis, M; Markwardt, C B; Chakrabarty, Deepto; Morgan, Edward H.; Muno, Michael P.; Galloway, Duncan K.; Wijnands, Rudy; Klis, Michiel van der; Markwardt, Craig B.

    2003-01-01

    Millisecond pulsars are neutron stars (NSs) that are thought to have been spun-up by mass accretion from a stellar companion. It is unknown whether there is a natural brake for this process, or if it continues until the centrifugal breakup limit is reached at submillisecond periods. Many NSs that are accreting from a companion exhibit thermonuclear X-ray bursts that last tens of seconds, caused by unstable nuclear burning on their surfaces. Millisecond brightness oscillations during bursts from ten NSs (as distinct from other rapid X-ray variability that is also observed) are thought to measure the stellar spin, but direct proof of a rotational origin has been lacking. Here, we report the detection of burst oscillations at the known spin frequency of an accreting millisecond pulsar, and we show that these oscillations always have the same rotational phase. This firmly establishes burst oscillations as nuclear-powered pulsations tracing the spin of accreting NSs, corroborating earlier evidence. The distributio...

  19. MA 222 - Exam 3 Statistics (scores are out of 100 points maximum ...

    E-Print Network [OSTI]

    2012-12-04

    Statistics (scores are out of 100 points maximum): Section. 031. 061. # Entered. 30. 29. Average. 64.46 60.55. Max. 94. 91. Min. 39. 21. Standard Deviation 15.3.

  20. MA 222 - Exam 1 Statistics (scores are out of 100 points maximum ...

    E-Print Network [OSTI]

    2012-09-26

    Statistics (scores are out of 100 points maximum): Section. 031. 061. # Entered. 30. 34. Average. 64.47 66.74. Max. 99. 94. Min. 18. 14. Standard Deviation 19.65

  1. Microcontroller Servomotor for Maximum Effective Power Point for Solar Cell System 

    E-Print Network [OSTI]

    Al-Khalidy, M.; Al-Rawi, O.; Noaman, N.

    2010-01-01

    In this paper a Maximum Power point (MPP) tracking algorithm is developed using dual-axis servomotor feedback tracking control system. An efficient and accurate servomotor system is used to increase the system efficiency ...

  2. Computation of the maximum loadability of a power system using nonlinear optimization 

    E-Print Network [OSTI]

    Khabirov, Abdufarrukh

    2001-01-01

    In recent years, power systems have undergone radical changes by becoming deregulated. Many electric companies have met new requirements and found ways to keep up with the changes in power systems. Issues of transfer capability and maximum...

  3. Submodule Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications

    E-Print Network [OSTI]

    Pilawa-Podgurski, Robert C. N.

    This paper explores the benefits of distributed power electronics in solar photovoltaic applications through the use of submodule integrated maximum power point trackers (MPPT). We propose a system architecture that provides ...

  4. Atlantic Ocean circulation at the last glacial maximum : inferences from data and models

    E-Print Network [OSTI]

    Dail, Holly Janine

    2012-01-01

    This thesis focuses on ocean circulation and atmospheric forcing in the Atlantic Ocean at the Last Glacial Maximum (LGM, 18-21 thousand years before present). Relative to the pre-industrial climate, LGM atmospheric CO? ...

  5. Maximum a Posteriori Models for Cortical Modeling: Feature Detectors, Topography and Modularity

    E-Print Network [OSTI]

    Weber, Cornelius

    Maximum a Posteriori Models for Cortical Modeling: Feature Detectors, Topography and Modularity Modeling: Feature Detectors, Topography and Modularity PhD Thesis by Cornelius Weber, Berlin, July 31, 2000

  6. Models for estimating saturation flow and maximum demand at closely spaced intersections 

    E-Print Network [OSTI]

    Nanduri, Sreelata

    1995-01-01

    This thesis describes models for saturation flow and maximum demand at closely spaced intersections. The effects of queue interaction between these two intersections are taken into account in both models. The saturation flow model is based...

  7. Author's personal copy Unified behaviour of maximum soot yields of methane, ethane and propane

    E-Print Network [OSTI]

    Gülder, Ömer L.

    Author's personal copy Unified behaviour of maximum soot yields of methane, ethane and propane the current study and the previous measurements in similar flames with methane, ethane, and propane flames

  8. What if CLIQUE were fast? Maximum Cliques in Information Networks and Strong Components in Temporal Networks

    E-Print Network [OSTI]

    Rossi, Ryan A; Gebremedhin, Assefaw H; Patwary, Md Mostofa Ali

    2012-01-01

    Exact maximum clique finders have progressed to the point where we can investigate cliques in million-node social and information networks, as well as find strongly connected components in temporal networks. We use one such finder to study a large collection of modern networks emanating from biological, social, and technological domains. We show inter-relationships between maximum cliques and several other common network properties, including network density, maximum core, and number of triangles. In temporal networks, we find that the largest temporal strong components have around 20-30% of the vertices of the entire network. These components represent groups of highly communicative individuals. In addition, we discuss and improve the performance and utility of the maximum clique finder itself.

  9. Maximum Likelihood Estimation for the Proportional Odds Model with Random Effects

    E-Print Network [OSTI]

    Zeng, Donglin

    Maximum Likelihood Estimation for the Proportional Odds Model with Random Effects DONGLIN ZENG, D. Y. LIN, and GUOSHENG YIN In this article, we study the semiparametric proportional odds model; Frailty model; Linear transformation model; Proportional hazards; Semiparametric efficiency; Survival data

  10. A Maximum Likelihood Method with Penalty to Estimate Link Travel Time Based on Trip Itinerary Data 

    E-Print Network [OSTI]

    Zhong, Chujun

    2014-12-15

    Travel time is an important network performance measure. It is a challenging subject due to the fluctuations in traffic characteristics, such as traffic flow. This study proposes a maximum likelihood method with penalty ...

  11. Variability Aware Network Utility Maximization

    E-Print Network [OSTI]

    Joseph, Vinay

    2011-01-01

    Network Utility Maximization (NUM) provides the key conceptual framework to study resource allocation amongst a collection of users/entities across disciplines as diverse as economics, law and engineering. In network engineering, this framework has been particularly insightful towards understanding how Internet protocols allocate bandwidth, and motivated diverse research on distributed mechanisms to maximize network utility while incorporating new relevant constraints, on energy/power, storage, stability, etc., for systems ranging from communication networks to the smart-grid. However when the available resources and/or users' utilities vary over time, a user's allocations will tend to vary, which in turn may have a detrimental impact on the users' utility or quality of experience. This paper introduces a generalized NUM framework which explicitly incorporates the detrimental impact of temporal variability in a user's allocated rewards. It explicitly incorporates tradeoffs amongst the mean and variability in ...

  12. 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).

  13. Massive Variability Surveys from Venezuela

    E-Print Network [OSTI]

    Cesar Briceno

    2003-04-03

    At the Venezuela National Astronomical Observatory we are carrying out variability surveys spanning many hundreds of square degrees near the celestial equator, using an 8k x 8k CCD Mosaic Camera optimized for drift-scanning on a 1m Schmidt telescope. Among the initial efforts was a project to obtain the first moderately deep, homogeneous sample of young stars over an area of ~180sqr.deg. encompassing the entire Orion OB1 association, one of the nearest and most active regions of star formation. The results show that variability is a powerful technique to identify pre-main sequence populations, specially in sparse areas devoid of gas and dust. We are currently developing a massive database, equipped with web-based data mining tools, that will make our data and results available to the astronomical community.

  14. Century-scale movement of the Atlantic Intertropical Convergence Zone linked to solar variability

    E-Print Network [OSTI]

    South Florida, University of

    Century-scale movement of the Atlantic Intertropical Convergence Zone linked to solar variability R June 2004. [1] The abundance of the planktic foraminifer Globigerinoides sacculifer in Gulf of Mexico-scale periodicity observed in proxy records of solar variability, which suggests that the average position

  15. X-RAYRICH GAMMA-RAY BURSTS, PHOTOSPHERES, AND VARIABILITY P. Meszaros,1,2

    E-Print Network [OSTI]

    Zhang, Bing

    X-RAY­RICH GAMMA-RAY BURSTS, PHOTOSPHERES, AND VARIABILITY P. Me´sza´ros,1,2 E. Ramirez-Ruiz,3 M. J of the observational gamma-ray variability-luminosity relation. Subject headings: gamma rays: bursts -- radiation mechanisms: nonthermal 1. INTRODUCTION Gamma-ray burst (GRB) light curves at gamma-ray ener- gies are often

  16. 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.

  17. The role of an accretion disk in AGN variability

    E-Print Network [OSTI]

    B. Czerny

    2004-09-10

    Optically thick accretion disks are considered to be important ingredients of luminous AGN. The claim of their existence is well supported by observations and recent years brought some progress in understanding of their dynamics. However, the role of accretion disks in optical/UV/X-ray variability of AGN is not quite clear. Most probably, in short timescales the disk reprocesses the variable X-ray flux but at longer timescales the variations of the disk structure lead directly to optical/UV variations as well as affect, or even create, the X-ray variability pattern. We urgently need a considerable progress in time-dependent disk models to close the gap between the theory and the stream of data coming from the AGN monitoring.

  18. Definition of a Random Variable Distribution Functions Properties of Distribution Functions Random Variables and Distribution Functions

    E-Print Network [OSTI]

    Watkins, Joseph C.

    Definition of a Random Variable Distribution Functions Properties of Distribution Functions Topic 7 Random Variables and Distribution Functions Distribution Functions 1 / 11 #12;Definition of a Random Variable Distribution Functions Properties of Distribution Functions Outline Definition of a Random

  19. 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.

  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. Radial Velocity Variability of Field Brown Dwarfs

    E-Print Network [OSTI]

    Prato, L; Rice, E L; McLean, I S; Kirkpatrick, J D; Burgasser, A J; Kim, S S

    2015-01-01

    We present paper six of the NIRSPEC Brown Dwarf Spectroscopic Survey, an analysis of multi-epoch, high-resolution (R~20,000) spectra of 25 field dwarf systems (3 late-type M dwarfs, 16 L dwarfs, and 6 T dwarfs) taken with the NIRSPEC infrared spectrograph at the W. M. Keck Observatory. With a radial velocity precision of ~2 km/s, we are sensitive to brown dwarf companions in orbits with periods of a few years or less given a mass ratio of 0.5 or greater. We do not detect any spectroscopic binary brown dwarfs in the sample. Given our target properties, and the frequency and cadence of observations, we use a Monte Carlo simulation to determine the detection probability of our sample. Even with a null detection result, our 1 sigma upper limit for very low mass binary frequency is 18%. Our targets included 7 known, wide brown dwarf binary systems. No significant radial velocity variability was measured in our multi-epoch observations of these systems, even for those pairs for which our data spanned a significant ...

  2. H\\alpha\\ Emission Variability in Active M Dwarfs

    E-Print Network [OSTI]

    Bell, Keaton J; Davenport, James R A; Hawley, Suzanne L; West, Andrew A; Rogel, Allen B

    2011-01-01

    We use ~12,000 spectra of ~3,500 magnetically active M0-M9 dwarfs from the Sloan Digital Sky Survey taken at 10-15 minute intervals, together with ~300 spectra of ~60 M0-M8 stars obtained hourly with the Hydra multi-object spectrometer, to probe H\\alpha\\ variability on timescales of minutes to weeks. With multiple observations for every star examined, we are able to characterize fluctuations in H\\alpha emission as a function of activity strength and spectral type. Stars with greater magnetic activity (as quantified by L_H\\alpha/L_bol) are found to be less variable at all spectral types. We attribute this result to the stronger level of persistent emission in the high activity stars, requiring a larger heating event in order to produce measurable variability. We also construct H\\alpha\\ structure functions to constrain the timescale of variability. The more active objects with lower variability exhibit a characteristic timescale longer than an hour, likely due to larger, longer lasting heating events, while the...

  3. The Cloud Computing and Other Variables

    E-Print Network [OSTI]

    Borjon-Kubota, Martha Estela

    2011-01-01

    12. Fragments in Six 13. Cloud Computing 14. Phase 15.Note 48. Devoured vi Cloud Computing and other Variables I.CALIFORNIA RIVERSIDE Cloud Computing and Other Variables A

  4. 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.

  5. Thermoacoustic and Photoacoustic Tomography with a variable ...

    E-Print Network [OSTI]

    Plamen Stefanov

    2010-11-09

    ... a joint work with. Jianliang Qian, Gunther Uhlmann and Hongkai Zhao. Plamen Stefanov (Purdue University ). Thermoacoustic Tomography, Variable Speed.

  6. 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.

  7. 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).

  8. The optical variability of the narrow line Seyfert 1 galaxy IRAS 13224-3809

    E-Print Network [OSTI]

    A. J. Young; C. S. Crawford; A. C. Fabian; W. N. Brandt; P. T. O'Brien

    1999-03-09

    We report on a short optical monitoring programme of the narrow-line Seyfert 1 Galaxy IRAS 13224-3809. Previous X-ray observations of this object have shown persistent giant variability. The degree of variability at other wavelengths may then be used to constrain the conditions and emission processes within the nucleus. Optical variability is expected if the electron population responsible for the soft X-ray emission is changing rapidly and Compton-upscattering infrared photons in the nucleus, or if the mechanism responsible for X-ray emission causes all the emission processes to vary together. We find that there is no significant optical variability with a firm upper limit of 2 per cent and conclude that the primary soft X-ray emission region produces little of the observed optical emission. The X-ray and optical emission regions must be physically distinct and any reprocessing of X-rays into the optical waveband occurs some distance from the nucleus. The lack of optical variability indicates that the energy density of infrared radiation in the nucleus is at most equal to that of the ultraviolet radiation since little is upscattered into the optical waveband. The extremely large X-ray variability of IRAS 13224-3809 may be explained by relativistic boosting of more modest variations. Although such boosting enhances X-ray variability over optical variability, this only partially explains the lack of optical variability.

  9. Cepheid Variables and their Application to the Cosmological Distance Scale 

    E-Print Network [OSTI]

    Hoffmann, Samantha L

    2013-05-02

    . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3. DIFFERENCE IMAGING ANALYSIS OF TYPE IA SUPERNOVA HOST NGC 5584 FOR CEPHEID VARIABLES . . . . . . . . . . . . . . . . . . 63 3.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 3.2 Observations and Data Reduction... and type Ia supernovae (SNe Ia). This cosmological distance scale started with a geometric distance measurement of Cepheids, such as parallaxes by [5]. The Cepheid Period-Luminosity relation was characterized by [79] for use as a primary distance...

  10. 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.

  11. The unusual photometric variability of the PMS star GM Cep

    E-Print Network [OSTI]

    Semkov, E; Peneva, S; Milanov, T; Stoyanov, K; Stateva, I; Kjurkchieva, D; Dimitrov, D; Radeva, V

    2015-01-01

    Results from UBVRI photometric observations of the pre-main sequence star GM Cep obtained in the period April 2011 - August 2014 are reported in the paper. Presented data are a continuation of our photometric monitoring of the star started in 2008. GM Cep is located in the field of the young open cluster Trumpler 37 and over the past years it has been an object of intense photometric and spectral studies. The star shows a strong photometric variability interpreted as a possible outburst from EXor type in previous studies. Our photometric data for a period of over six years show a large amplitude variability (Delta V ~ 2.3 mag.) and several deep minimums in brightness are observed. The analysis of the collected multicolor photometric data shows the typical of UX Ori variables a color reversal during the minimums in brightness. The observed decreases in brightness have a different shape, and evidences of periodicity are not detected. At the same time, high amplitude rapid variations in brightness typical for th...

  12. Photometric Variability in the CSTAR Field: Results From the 2008 Data Set

    E-Print Network [OSTI]

    Wang, Songhu; Zhou, Xu; Zhou, Ji-Lin; Fu, Jian-Ning; Yang, Ming; Liu, Huigen; Xie, Jiwei; Wang, Lifan; Wang, Lingzhi; Wittenmyer, R A; Ashley, M C B; Feng, Long-Long; Gong, Xuefei; Lawrence, J S; Liu, Qiang; Luong-Van, D M; Ma, Jun; Peng, Xiyan; Storey, J W V; Wu, Zhenyu; Yan, Jun; Yang, Huigen; Yang, Ji; Yuan, Xiangyan; Zhang, Tianmeng; Zhang, Xiaojia; Zhu, Zhenxi; Zou, Hu

    2015-01-01

    The Chinese Small Telescope ARray (CSTAR) is the first telescope facility built at Dome A, Antarctica. During the 2008 observing season, the installation provided long-baseline and high-cadence photometric observations in the i-band for 18,145 targets within 20 deg2 CSTAR field around the South Celestial Pole for the purpose of monitoring the astronomical observing quality of Dome A and detecting various types of photometric variability. Using sensitive and robust detection methods, we discover 274 potential variables from this data set, 83 of which are new discoveries. We characterize most of them, providing the periods, amplitudes and classes of variability. The catalog of all these variables is presented along with the discussion of their statistical properties.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Atomic Collapse Observed

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

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  20. A Three-Decade Outburst of the LMC Luminous Blue Variable R127 Draws to a Close

    E-Print Network [OSTI]

    Nolan R. Walborn; Otmar Stahl; Roberto C. Gamen; Thomas Szeifert; Nidia I. Morrell; Nathan Smith; Ian D. Howarth; Roberta M. Humphreys; Howard E. Bond; Daniel J. Lennon

    2008-07-09

    The paradigmatic Luminous Blue Variable R127 in the Large Magellanic Cloud has been found in the intermediate, peculiar early-B state, and substantially fainter in visual light, signaling the final decline from its major outburst that began between 1978 and 1980. This transformation was detected in 2008 January, but archival data show that it began between early 2005 and early 2007. In fact, significant changes from the maximum, peculiar A-type spectrum, which was maintained from 1986 through 1998, had already begun the following year, coinciding with a steep drop in visual light. We show detailed correspondences between the spectrum and light, in which the decline mimics the rise. Moreover, these trends are not monotonic but are characterized by multiple spikes and dips, which may provide constraints on the unknown outburst mechanism. Intensive photometric and spectroscopic monitoring of R127 should now resume, to follow the decline presumably back to the quiescent Ofpe/WN9 state, in order to fully document the remainder of this unique observational opportunity.

  1. Basic Theory in Construction of Boolean Functions with Maximum Possible Annihilator Immunity

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Basic Theory in Construction of Boolean Functions with Maximum Possible Annihilator Immunity #3. In this paper we present a construction keeping in mind the basic theory of annihilator immunity the basic theory. Most importantly, the cryptographic properties of our constructions, such as nonlinearity

  2. Basic Theory in Construction of Boolean Functions with Maximum Possible Annihilator Immunity

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Basic Theory in Construction of Boolean Functions with Maximum Possible Annihilator Immunity Deepak present a construction keeping in mind the basic theory of annihilator immunity. This construction immunity that comes from the basic theory. Most importantly, the cryptographic properties of our

  3. Energy Production, Frictional Dissipation, and Maximum Intensity of a Numerically Simulated Tropical Cyclone

    E-Print Network [OSTI]

    Wang, Yuqing

    0 Energy Production, Frictional Dissipation, and Maximum Intensity of a Numerically Simulated is eventually dissipated due to surface friction. Since the energy production rate is a linear function while intensifies. When the dissipation rate eventually reaches the production rate, the TC has no excess energy

  4. Energy Production, Frictional Dissipation, and Maximum Intensity of a Numerically Simulated Tropical Cyclone*

    E-Print Network [OSTI]

    Wang, Yuqing

    Energy Production, Frictional Dissipation, and Maximum Intensity of a Numerically Simulated is eventually dissipated due to surface friction. Since the energy production rate is a linear function while intensifies. When the dissipation rate eventually reaches the production rate, the TC has no excess energy

  5. Linearized semiclassical initial value time correlation functions with maximum entropy analytic continuation

    E-Print Network [OSTI]

    Miller, William H.

    Linearized semiclassical initial value time correlation functions with maximum entropy analytic procedure to be a very significant enhancement of the LSC-IVR for correlation functions of both linear method is used to extend the range of accuracy of the linearized semiclassical initial value

  6. Regression Model for Daily Maximum Stream Temperature David W. Neumann1

    E-Print Network [OSTI]

    Balaji, Rajagopalan

    Regression Model for Daily Maximum Stream Temperature David W. Neumann1 ; Balaji Rajagopalan2 for the summer period. The model is created using a stepwise linear regression procedure to select significant-9372 2003 129:7 667 CE Database subject headings: Decision support systems; Regression models; California

  7. Sub-Module Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications

    E-Print Network [OSTI]

    Perreault, Dave

    Sub-Module Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications explores the benefits of distributed power electronics in solar photovoltaic applications through the use, interest in renewable energy sources has in- creased. Among these, solar photovoltaic (PV) energy has seen

  8. Sub-Module Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications

    E-Print Network [OSTI]

    Perreault, Dave

    Sub-Module Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications 2012. Abstract--This paper explores the benefits of distributed power electronics in solar photovoltaic, interest in renewable energy sources has in- creased. Among these, solar photovoltaic (PV) energy has seen

  9. Power and Sample Size Determination for a Stepwise Test Procedure for Finding the Maximum Safe Dose

    E-Print Network [OSTI]

    Tamhane, Ajit C.

    Power and Sample Size Determination for a Stepwise Test Procedure for Finding the Maximum Safe Dose This paper addresses the problem of power and sample size calculation for a stepwise multiple test procedure of a compound. A general expression for the power of this procedure is derived. It is used to find the minimum

  10. 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.

  11. Maximum CME speed as an indicator of solar and geomagnetic activities , V.B. Yurchyshyn1

    E-Print Network [OSTI]

    relationships with one another. Although the relationship between the solar and geomagnetic activity indices hasMaximum CME speed as an indicator of solar and geomagnetic activities A. Kilcik1 , V.B. Yurchyshyn1 , V. Abramenko1 , P.R. Goode1 , N. Gopalswamy2 , A. Ozguc3 , J.P. Rozelot4 1 Big Bear Solar

  12. Extraction of Spectral Functions from Dyson-Schwinger Studies via the Maximum Entropy Method

    E-Print Network [OSTI]

    Dominik Nickel

    2006-07-20

    It is shown how to apply the Maximum Entropy Method (MEM) to numerical Dyson-Schwinger studies for the extraction of spectral functions of correlators from their corresponding Euclidean propagators. Differences to the application in lattice QCD are emphasized and, as an example, the spectral functions of massless quarks in cold and dense matter are presented.

  13. Design of wind farm layout for maximum wind energy capture Andrew Kusiak*, Zhe Song

    E-Print Network [OSTI]

    Kusiak, Andrew

    of reducing the cost of producing wind power: for example, the site selection, site layout design, predictiveDesign of wind farm layout for maximum wind energy capture Andrew Kusiak*, Zhe Song Intelligent Accepted 24 August 2009 Available online 22 September 2009 Keywords: Wind farm Wind turbine Layout design

  14. Performance of Photovoltaic Maximum Power Point Tracking Algorithms in the Presence of Noise

    E-Print Network [OSTI]

    Odam, Kofi

    Performance of Photovoltaic Maximum Power Point Tracking Algorithms in the Presence of Noise tracking (MPPT) algorithms for photovoltaic systems, including how noise affects both tracking speed-performance photovoltaic sys- tems. An intelligent controller adjusts the voltage, current, or impedance seen by a solar

  15. Experimental evaluation of algorithmic solutions for the maximum generalised network ow problem

    E-Print Network [OSTI]

    Radzik, Tomasz

    ; Tomasz Radzik y King's College London Shengxiang Yang z University of Leicester Department of Computer Science, King's College London Technical Report TR-01-09 December 2001 Abstract The maximum generalised problem models some optimisation problems arising in manufacturing, transportation and #12;nancial

  16. Recursive maximum likelihood estimation for structural health monitoring: Kalman and particle filter implementations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Recursive maximum likelihood estimation for structural health monitoring: Kalman and particle by a likelihood approach. In a first part the structural health monitoring problem is written in term of recursive al [6] in a more simple framework. Particle approximation for health monitoring was already proposed

  17. Operations Research Letters 21 (1997) 211217 An algorithm for nding a maximum clique in a graph

    E-Print Network [OSTI]

    Wood, David R.

    1997-01-01

    . We denote the set of vertices adjacent to vV by NG(v) and the subgraph of G induced by S V by G a vertex vS with maximum degree in G, and set Q := Q {v} and S := S NG(v). We now turn our attention

  18. An Analysis of the Maximum Drawdown Risk Malik Magdon-Ismail

    E-Print Network [OSTI]

    Magdon-Ismail, Malik

    Engineering Cairo University Giza, Egypt. amir@alumni.caltech.edu Introduction. The maximum cumulative loss to the Calmar ratio is the Sterling ratio, Sterling(T) = Return over [0,T ] MDD over [0,T ]-10% , and our discussion applies equally well to the Sterling ratio. 1 #12;primarily due to a lack of an analytical

  19. An Analysis of the Maximum Drawdown Risk Malik MagdonIsmail

    E-Print Network [OSTI]

    Magdon-Ismail, Malik

    Engineering Cairo University Giza, Egypt. amir@alumni.caltech.edu Introduction. The maximum cumulative loss is not prevalent 1 Similar to the Calmar ratio is the Sterling ratio, Sterling(T ) = Return over [0,T ] MDD over [0,T ]-10% , and our discussion applies equally well to the Sterling ratio. 1 #12; primarily due

  20. Mathematical Geology, Vol. 30, No. 3, 1998 A Bootstrap Test Using Maximum Likelihood Ratio

    E-Print Network [OSTI]

    Chatterjee, Snigdhansu

    Mathematical Geology, Vol. 30, No. 3, 1998 A Bootstrap Test Using Maximum Likelihood Ratio 24 January 1997; revised 10 May 1997. 2Geological Studies Unit, Indian Statistical Institute, 203 B-8121/98/0400-0275$15.00/1 © 1998 International Association for Mathematical Geology KEY WORDS: polar coordinates, joint frequency

  1. Maximum size of drops levitated by an air cushion Jacco H. Snoeijer,1,2

    E-Print Network [OSTI]

    Eggers, Jens

    , kept aloft by a stream of water vapor. We investigate the limit of small flow rates, for which the size for the manipulation of corrosive sub- stances 10 or the frictionless displacement of drops 6 . Of particular interest is the maximum drop size that can be sus- tained, and the limit of very small flow rates. The drop con- tinues

  2. Hydraulic limits on maximum plant transpiration and the emergence of the safetyefficiency trade-off

    E-Print Network [OSTI]

    Jackson, Robert B.

    Hydraulic limits on maximum plant transpiration and the emergence of the safety­efficiency trade.12126 Key words: hydraulic limitation, safety­ efficiency trade-off, soil­plant­atmosphere model, trait hydraulics constrain ecosystem productivity by setting physical limits to water transport and hence carbon

  3. MAximum Multicore POwer (MAMPO) -An Automatic Multithreaded Synthetic Power Virus Generation

    E-Print Network [OSTI]

    John, Lizy Kurian

    and cooling issues along with a world-wide initiative towards green computing, power consump- tion is a firstMAximum Multicore POwer (MAMPO) - An Automatic Multithreaded Synthetic Power Virus Generation worst case power consumption for a com- puter system is a significant design parameter and it is a very

  4. NOAA Technical Memorandum NWS HYDRO 39 PROBABLE MAXIMUM PRECIPITATION FOR THE UPPER

    E-Print Network [OSTI]

    NOAA Technical Memorandum NWS HYDRO 39 PROBABLE MAXIMUM PRECIPITATION FOR THE UPPER DEERFIELD RIVER The Office of Hydrology (HYDRO) of the National Weather Service (NWS) develops procedures for making river agencies, and conducts pertinent research and development. NOAA Technical Memorandums in the NWS HYDRO

  5. Relating maximum airway dilation and subsequent reconstriction to reactivity in human lungs

    E-Print Network [OSTI]

    Lutchen, Kenneth

    Relating maximum airway dilation and subsequent reconstriction to reactivity in human lungs Lauren in human lungs. J Appl Physiol 96: 1808­1814, 2004. First published February 6, 2004; 10.1152/japplphysiol reactivity in healthy lungs by prohibiting DI for an extended period. The present study had two goals. First

  6. Study of Different Implementation Approaches for a Maximum Power Point Florent Boico Brad Lehman

    E-Print Network [OSTI]

    Lehman, Brad

    of solar panels has limited their use. As the efficiency is limited, harvesting the maximum amount no other source is available. However, these solar panels have lower efficiency than average solar cells in suddenly changing illumination conditions. Solar Panels have been used for decades to generate electricity

  7. Aalborg Universitet Individual Module Maximum Power Point Tracking for a Thermoelectric Generator

    E-Print Network [OSTI]

    Schaltz, Erik

    Aalborg Universitet Individual Module Maximum Power Point Tracking for a Thermoelectric Generator Tracking for a Thermoelectric Generator Systems. Poster session presented at The 31st International & 10th Generator Systems Casper Vadstrup (cvdst08@student.aau.dk), Min Chen (mch@et.aau.dk), Erik Schaltz (esc

  8. The probable value of the Lovasz-Schrijver relaxations for maximum independent set

    E-Print Network [OSTI]

    Krauthgamer, Robert

    Introduction Let G(V, E) be a graph on n vertices. An independent set (a.k.a. stable set) in G is a subset an independent set of maximum size in an input graph G. The independence number (a.k.a. stability number) of G

  9. The probable value of the LovaszSchrijver relaxations for maximum independent set #

    E-Print Network [OSTI]

    Krauthgamer, Robert

    Introduction Let G(V, E) be a graph on n vertices. An independent set (a.k.a. stable set) in G is a subset an independent set of maximum size in an input graph G. The independence number (a.k.a. stability number) of G

  10. Sufficient Stochastic Maximum Principle in a Regime-Switching Diffusion Model

    SciTech Connect (OSTI)

    Donnelly, Catherine, E-mail: C.Donnelly@hw.ac.uk [Heriot-Watt University, Department of Actuarial Mathematics and Statistics (United Kingdom)

    2011-10-15

    We prove a sufficient stochastic maximum principle for the optimal control of a regime-switching diffusion model. We show the connection to dynamic programming and we apply the result to a quadratic loss minimization problem, which can be used to solve a mean-variance portfolio selection problem.

  11. On Finding the Maximum Number of Disjoint Cuts in Seymour Graphs ?

    E-Print Network [OSTI]

    Ageev, Alexandr

    On Finding the Maximum Number of Disjoint Cuts in Seymour Graphs ? Alexander A. Ageev Sobolev. In this paper we prove that the problem is polynomially solvable on Seymour graphs which include both all bipar is polynomially solvable when restricted to the family of Seymour graphs. To present a rigorous definition

  12. PHYSICAL REVIEW E 86, 041144 (2012) Efficiency at maximum power for classical particle transport

    E-Print Network [OSTI]

    Lindenberg, Katja

    2012-01-01

    PHYSICAL REVIEW E 86, 041144 (2012) Efficiency at maximum power for classical particle transport transport. DOI: 10.1103/PhysRevE.86.041144 PACS number(s): 05.70.Ln, 05.40.-a, 05.20.-y I. INTRODUCTION Over, operating between a hot and cold bath at temperatures T (1) and T (2) , respectively, possesses universal

  13. Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating

    E-Print Network [OSTI]

    Harrington, Jerry Y.

    Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating CHRISTOPHER M. HARTMAN AND JERRY Y. HARRINGTON Department of Meteorology, The Pennsylvania November 2004) ABSTRACT The effects of solar heating and infrared cooling on the vapor depositional growth

  14. Physical observability of horizons

    E-Print Network [OSTI]

    Matt Visser

    2014-11-25

    Event horizons are (generically) not physically observable. In contrast, apparent horizons (and the closely related trapping horizons) are generically physically observable --- in the sense that they can be detected by observers working in finite-size regions of spacetime. Consequently event horizons are inappropriate tools for defining astrophysical black holes, or indeed for defining any notion of evolving}black hole, (evolving either due to accretion or Hawking radiation). The only situation in which an event horizon becomes physically observable is for the very highly idealized stationary or static black holes, when the event horizon is a Killing horizon which is degenerate with the apparent and trapping horizons; and then it is the physical observability of the apparent/trapping horizons that is fundamental --- the event horizon merely comes along for the ride.

  15. Physical observability of horizons

    E-Print Network [OSTI]

    Visser, Matt

    2014-01-01

    Event horizons are (generically) not physically observable. In contrast, apparent horizons (and the closely related trapping horizons) are generically physically observable --- in the sense that they can be detected by observers working in finite-size regions of spacetime. Consequently event horizons are inappropriate tools for defining astrophysical black holes, or indeed for defining any notion of evolving}black hole, (evolving either due to accretion or Hawking radiation). The only situation in which an event horizon becomes physically observable is for the very highly idealized stationary or static black holes, when the event horizon is a Killing horizon which is degenerate with the apparent and trapping horizons; and then it is the physical observability of the apparent/trapping horizons that is fundamental --- the event horizon merely comes along for the ride.

  16. Using the Maximum X-ray Flux Ratio and X-ray Background to Predict Solar Flare Class

    E-Print Network [OSTI]

    Winter, Lisa M

    2015-01-01

    We present the discovery of a relationship between the maximum ratio of the flare flux (namely, 0.5-4 Ang to the 1-8 Ang flux) and non-flare background (namely, the 1-8 Ang background flux), which clearly separates flares into classes by peak flux level. We established this relationship based on an analysis of the Geostationary Operational Environmental Satellites (GOES) X-ray observations of ~ 50,000 X, M, C, and B flares derived from the NOAA/SWPC flares catalog. Employing a combination of machine learning techniques (K-nearest neighbors and nearest-centroid algorithms) we show a separation of the observed parameters for the different peak flaring energies. This analysis is validated by successfully predicting the flare classes for 100% of the X-class flares, 76% of the M-class flares, 80% of the C-class flares and 81% of the B-class flares for solar cycle 24, based on the training of the parametric extracts for solar flares in cycles 22-23.

  17. Variability in Automated Responses of Commercial Buildings and Industrial Facilities to Dynamic Electricity Prices

    SciTech Connect (OSTI)

    Mathieu, Johanna L.; Callaway, Duncan S.; Kiliccote, Sila

    2011-08-16

    Changes in the electricity consumption of commercial buildings and industrial facilities (C&I facilities) during Demand Response (DR) events are usually estimated using counterfactual baseline models. Model error makes it difficult to precisely quantify these changes in consumption and understand if C&I facilities exhibit event-to-event variability in their response to DR signals. This paper seeks to understand baseline model error and DR variability in C&I facilities facing dynamic electricity prices. Using a regression-based baseline model, we present a method to compute the error associated with estimates of several DR parameters. We also develop a metric to determine how much observed DR variability results from baseline model error rather than real variability in response. We analyze 38 C&I facilities participating in an automated DR program and find that DR parameter errors are large. Though some facilities exhibit real DR variability, most observed variability results from baseline model error. Therefore, facilities with variable DR parameters may actually respond consistently from event to event. Consequently, in DR programs in which repeatability is valued, individual buildings may be performing better than previously thought. In some cases, however, aggregations of C&I facilities exhibit real DR variability, which could create challenges for power system operation.

  18. Examining Uncertainty in Demand Response Baseline Models and Variability in Automated Response to Dynamic Pricing

    SciTech Connect (OSTI)

    Mathieu, Johanna L.; Callaway, Duncan S.; Kiliccote, Sila

    2011-08-15

    Controlling electric loads to deliver power system services presents a number of interesting challenges. For example, changes in electricity consumption of Commercial and Industrial (C&I) facilities are usually estimated using counterfactual baseline models, and model uncertainty makes it difficult to precisely quantify control responsiveness. Moreover, C&I facilities exhibit variability in their response. This paper seeks to understand baseline model error and demand-side variability in responses to open-loop control signals (i.e. dynamic prices). Using a regression-based baseline model, we define several Demand Response (DR) parameters, which characterize changes in electricity use on DR days, and then present a method for computing the error associated with DR parameter estimates. In addition to analyzing the magnitude of DR parameter error, we develop a metric to determine how much observed DR parameter variability is attributable to real event-to-event variability versus simply baseline model error. Using data from 38 C&I facilities that participated in an automated DR program in California, we find that DR parameter errors are large. For most facilities, observed DR parameter variability is likely explained by baseline model error, not real DR parameter variability; however, a number of facilities exhibit real DR parameter variability. In some cases, the aggregate population of C&I facilities exhibits real DR parameter variability, resulting in implications for the system operator with respect to both resource planning and system stability.

  19. Observables on Quantum Structures

    E-Print Network [OSTI]

    Anatolij Dvure?enskij; Mária Kuková

    2012-04-29

    An observable on a quantum structure is any $\\sigma$-homomorphism of quantum structures from the Borel $\\sigma$-algebra into the quantum structure. We show that our partial information on an observable known only for all intervals of the form $(-\\infty,t)$ is sufficient to determine uniquely the whole observable defined on quantum structures like $\\sigma$-MV-algebras, $\\sigma$-effect algebras, Boolean $\\sigma$-algebras, monotone $\\sigma$-complete effect algebras with the Riesz Decomposition Property, the effect algebra of effect operators of a Hilbert space, and a system of functions, and an effect-tribe.

  20. Constraining FeLoBAL outflows from absorption line variability

    E-Print Network [OSTI]

    McGraw, S M; Hamann, F W; Capellupo, D M; Gallagher, S C; Brandt, W N

    2015-01-01

    FeLoBALs are a rare class of quasar outflows with low-ionization broad absorption lines (BALs), large column densities, and potentially large kinetic energies that might be important for `feedback' to galaxy evolution. In order to probe the physical properties of these outflows, we conducted a multiple-epoch, absorption line variability study of 12 FeLoBAL quasars spanning a redshift range between 0.7 and 1.9 over rest frame time-scales of approximately 10 d to 7.6 yr. We detect absorption line variability with greater than 8 sigma confidence in 3 out of the 12 sources in our sample over time-scales of 0.6 to 7.6 yr. Variable wavelength intervals are associated with ground and excited state Fe II multiplets, the Mg II 2796, 2803 doublet, Mg I 2852, and excited state Ni II multiplets. The observed variability along with evidence of saturation in the absorption lines favors transverse motions of gas across the line of sight (LOS) as the preferred scenario, and allows us to constrain the outflow distance from th...

  1. How many Hipparcos Variability-Induced Movers are genuine binaries?

    E-Print Network [OSTI]

    Pourbaix, D; Detournay, S; Jorissen, A; Knapp, G; Makarov, V V

    2003-01-01

    Hipparcos observations of some variable stars, and especially of long-period (e.g. Mira) variables, reveal a motion of the photocenter correlated with the brightness variation ({variability-induced mover -- VIM), suggesting the presence of a binary companion. A re-analysis of the Hipparcos photometric and astrometric data does not confirm the VIM solution for 62 among the 288 VIM objects (21%) in the Hipparcos catalogue. Most of these 288 VIMs are long-period (e.g. Mira) variables (LPV). The effect of a revised chromaticity correction, which accounts for the color variations along the light cycle, was then investigated. It is based on `instantaneous' $V-I$ color indices derived from Hipparcos and Tycho-2 epoch photometry. Among the 188 LPVs flagged as VIM in the Hipparcos catalogue, 89 (47%) are not confirmed as VIM after this improved chromaticity correction is applied. This dramatic decrease in the number of VIM solutions is not surprising, since the chromaticity correction applied by the Hipparcos reductio...

  2. 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.

  3. Observations of Radio Giant Pulses with GAVRT

    E-Print Network [OSTI]

    Jones, Glenn

    2015-01-01

    Radio giant pulses provide a unique opportunity to study the pulsar radio emission mechanism in exquisite detail. Previous studies have revealed a wide range of properties and phenomena, including extraordinarily high brightness temperatures, sub-nanosecond emission features, and banded dynamic spectra. New measurements of giant pulse characteristics can help guide and test theoretical emission models. To this end, an extensive observation campaign has begun which will provide more than 500 hours on the Crab with a 34-meter antenna located in California, USA. The observations are being done as part of an educational outreach program called the Goldstone-Apple Valley Radio Telescope (GAVRT). This antenna has a novel wide bandwidth receiver which provides up to 8 GHz of instantaneous bandwidth in the range of 2.5 to 14 GHz. These observations will provide detailed information about the variability, amplitude distribution, and detailed frequency structure of radio giant pulses. In addition, a database of pulses ...

  4. 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.

  5. MARS OBSERVER Mission Failure

    E-Print Network [OSTI]

    Rhoads, James

    of Mars Observer Mission Failure.. ................... D-12 a. Most Probable Cause: Leakage of NT0 Through Check Valves .................................................................. D-14 b. Potential Cause: Pressure Regulator Failure....................... D-28 c. Potential Cause: Failure of a Pyro Valve Charge

  6. 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.

  7. 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?¹. 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.

  8. Algorithms for optimized maximum entropy and diagnostic tools for analytic continuation

    E-Print Network [OSTI]

    Bergeron, Dominic

    2015-01-01

    Analytic continuation of numerical data obtained in imaginary time or frequency has become an essential part of many branches of quantum computational physics. The maximum-entropy approach is the most widely used method whenever the data contains some numerical uncertainties, especially in Monte-Carlo based calculations. Here we present a highly optimized approach to maximum-entropy implemented in a freely available software that is both fast and accurate and offers quality-of-fit diagnostic tools. It can handle fermionic and bosonic input Green functions, self-energies, or correlation functions, both in Matsubara frequency or imaginary time, and with arbitrary covariance. All aspects of the implementation critical for accuracy and speed are optimized using specific numerical methods. A new way of choosing the optimal value of the entropy weight $\\alpha$ is also introduced. It is based on the identification of three different regimes in the value of $\\chi^2$ as a function of $\\alpha$: Large values of $\\alpha$...

  9. 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.

  10. REMARKS ON THE MAXIMUM ENTROPY METHOD APPLIED TO FINITE TEMPERATURE LATTICE QCD.

    SciTech Connect (OSTI)

    UMEDA, T.; MATSUFURU, H.

    2005-07-25

    We make remarks on the Maximum Entropy Method (MEM) for studies of the spectral function of hadronic correlators in finite temperature lattice QCD. We discuss the virtues and subtlety of MEM in the cases that one does not have enough number of data points such as at finite temperature. Taking these points into account, we suggest several tests which one should examine to keep the reliability for the results, and also apply them using mock and lattice QCD data.

  11. 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.

  12. Global convergence of diluted iterations in maximum-likelihood quantum tomography

    E-Print Network [OSTI]

    D. S. Gonçalves; M. A. Gomes-Ruggiero; C. Lavor

    2013-06-13

    In this paper we present an inexact stepsize selection for the Diluted R\\rho R algorithm, used to obtain the maximum likelihood estimate to the density matrix in quantum state tomography. We give a new interpretation for the diluted R\\rho R iterations that allows us to prove the global convergence under weaker assumptions. Thus, we propose a new algorithm which is globally convergent and suitable for practical implementation.

  13. Cataclysmic Variables from SDSS III. The Third Year

    E-Print Network [OSTI]

    Paula Szkody; Arne Henden; Oliver Fraser; Nicole Silvestri; John Bochanski; Michael A. Wolfe; Marcel Agüeros; Brian Warner; Patrick Woudt; Jonica Tramposch; Lee Homer; Gary Schmidt; Gillian R. Knapp; Scott F. Anderson; Kevin Covey; Hugh Harris; Suzanne Hawley; Donald P. Schneider; Wolfgang Voges; J. Brinkmann

    2004-07-08

    This paper continues the series that identifies new cataclysmic variables found in the Sloan Digital Sky Survey. We present 36 cataclysmic variables and one possible symbiotic star from Sloan spectra obtained during 2002, of which 34 are new discoveries, 2 are known dwarf novae (BC UMa, KS UMa) and one is a known CV identified from the 2dF survey. The positions, colors and spectra of all 37 systems are presented, along with follow-up spectroscopic/photometric observations of 10 systems. As in the past 2 years of data, the new SDSS systems show a large variety of characteristics based on their inclination and magnetic fields, including 3 eclipsing systems, 4 with prominent He II emission, and 15 systems showing features of the underlying stars.

  14. Chandra and ASCA Observations of the X-ray-brightest T-Tauri Stars in the Rho Ophiuchi Cloud

    E-Print Network [OSTI]

    Kensuke Imanishi; Masahiro Tsujimoto; Katsuji Koyama

    2002-02-15

    We present the Chandra ACIS and ASCA GIS results for a series of four long-term observations on DoAr 21, ROXs 21 and ROXs 31; the X-ray brightest T-Tauri stars (TTSs) in the Rho Ophiuchi cloud. In the four observations with a net exposure of ~600 ksec, we found six, three and two flares from DoAr 21, ROXs 21 and ROXs 31, respectively; hence the flare rate is fairly high. The spectra of DoAr 21 are well fitted with a single-temperature plasma model, while those of ROXs 21 and ROXs 31 need an additional soft plasma component. Since DoAr 21 is younger (~10^5 yr) than ROXs 21 and ROXs 31 (~10^6 yr), these results may indicate that the soft component gradually increases as T-Tauri stars age. The abundances are generally sub-solar and vary from element to element. Both high-FIP (first ionization potential) and low-FIP elements show enhancement over the mean abundances. An unusual giant flare is detected from ROXs 31. The peak luminosity and temperature are ~10^33 ergs s^-1 and ~10 keV, respectively. The temperature reaches its peak value before the flux maximum, and is nearly constant (4--5 keV) during the decay phase, indicating successive energy release during the flare. The abundances and absorption show dramatic variability from the quiescent to flare phase.

  15. Self-adjoint Lyapunov variables, temporal ordering and irreversible representations of Schroedinger evolution

    E-Print Network [OSTI]

    Y. Strauss

    2009-09-24

    In non relativistic quantum mechanics time enters as a parameter in the Schroedinger equation. However, there are various situations where the need arises to view time as a dynamical variable. In this paper we consider the dynamical role of time through the construction of a Lyapunov variable - i.e., a self-adjoint quantum observable whose expectation value varies monotonically as time increases. It is shown, in a constructive way, that a certain class of models admit a Lyapunov variable and that the existence of a Lyapunov variable implies the existence of a transformation mapping the original quantum mechanical problem to an equivalent irreversible representation. In addition, it is proved that in the irreversible representation there exists a natural time ordering observable splitting the Hilbert space at each t>0 into past and future subspaces.

  16. Self-adjoint Lyapunov variables, temporal ordering, and irreversible representations of Schroedinger evolution

    SciTech Connect (OSTI)

    Strauss, Y. [Einstein Institute of Mathematics, Hebrew University of Jerusalem, Jerusalem, 91904 (Israel)

    2010-02-15

    In nonrelativistic quantum mechanics time enters as a parameter in the Schroedinger equation. However, there are various situations where the need arises to view time as a dynamical variable. In this paper we consider the dynamical role of time through the construction of a Lyapunov variable - i.e., a self-adjoint quantum observable whose expectation value varies monotonically as time increases. It is shown, in a constructive way, that a certain class of models admits a Lyapunov variable and that the existence of a Lyapunov variable implies the existence of a transformation mapping the original quantum mechanical problem to an equivalent irreversible representation. In addition, it is proven that in the irreversible representation there exists a natural time ordering observable splitting the Hilbert space at each t>0 into past and future subspaces.

  17. Mexican drought: an observational modeling and tree ring study of variability and climate change

    E-Print Network [OSTI]

    2009-01-01

    CNA, 2006. Estadísticas del agua en México. Sistema NacionalCantidad, Calidad, Usos y Conservación del Agua, ComisiónNacional del Agua, México, D. F. , 201 pp. Dai A. , K. E.

  18. Observed 20th century desert dust variability: impact on climate and biogeochemistry

    E-Print Network [OSTI]

    2010-01-01

    Bhattacharya 3 , M. A. J. Curran 7,8 , M. G. Flanner 9 , F.Godwin, I. , Morgan, V. , Curran, M. A. J. , van Ommen, T.

  19. Observational study on variability between biobanks in the estimation of DNA concentration

    E-Print Network [OSTI]

    Brown, Jay; Donev, Alexander N.; Aslanidis, Charalampos; Bracegirdle, Pippa; Dixon, Katherine P.; Foedinger, Manuela; Gwilliam, Rhian; Hardy, Matthew; Illig, Thomas; Ke, Xiayi; Krinka, Dagni; Lagerberg, Camilla; Laiho, Paivi; Lewis, David H.; McArdle, Wendy; Jones, Richard W.; Patton, Simon; Ring, Susan M.; Schmitz, Gerd; Stevens, Helen; Tybring, Gunnel; Wichmann, H. Erich; Ollier, William E. R.; Yuille, Martin A.

    2009-10-13

    labelling (i.e. data quality). The single most substantial cause of exclusion appeared to be the failure of a DNA sample to attain a single nucleotide polymorphism call rate of >97%. This failure may arise from impurities in the sample, its lack... of repeat estimations from four repeats (one participant) to three (six partici- pants) and below. Statistical methods Statistical analysis of the data was carried out using the SAS JMP package [11]. A mixed effect model was fitted to the data, specifying...

  20. On the observed variability of the crosspolar cap potential W. A. Bristow,1

    E-Print Network [OSTI]

    Shepherd, Simon

    . Introduction [2] The cross­polar cap potential (PCP) parameterizes the degree to which solar wind energy field and the solar wind electric field maps directly along the field lines [e.g., Toffoletto and Hill Super Dual Auroral Radar Network (SuperDARN) during periods of steady interplanetary magnetic field (IMF

  1. Variability in wildfire emissions of nitrogen oxides as observed from space

    E-Print Network [OSTI]

    Mebust, Anna

    2013-01-01

    using wind at 850 hPa from the NCEP Climate Forecast Systemand wind vectors at 850 hPa from the Climate Forecast Systemwind fields from the National Centers for Environmental Prediction (NCEP) Climate Forecast

  2. Mexican drought: an observational modeling and tree ring study of variability and climate change

    E-Print Network [OSTI]

    2009-01-01

    Press, Boston, 324 pp. Rayner N. , D. Parker, E. Horton, C.from the HadISST data set (Rayner et al. , 2003) from 1870

  3. Mexican drought: an observational modeling and tree ring study of variability and climate change

    E-Print Network [OSTI]

    2009-01-01

    of the subtropical jet stream, eddy momentum fluxes and thewinter storm track and jet stream, and in the summer halfof the mid-latitude jet stream and storm tracks. The

  4. Mexican drought: an observational modeling and tree ring study of variability and climate change

    E-Print Network [OSTI]

    2009-01-01

    Mexico and in agricultural employment and continued out-migrationMéxico and Central America. Because of the northward migration and

  5. VARIABILITY IN RAINFALL DROP-SIZE DISTRIBUTIONS OBSERVED AT THE ARM DARWIN SITE

    E-Print Network [OSTI]

    Department/Atmospheric Sciences Division Brookhaven National Laboratory U.S. Department of Energy Office Associates, LLC under Contract No. DE-AC02- 98CH10886 with the U.S. Department of Energy. The publisher-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript

  6. VARIABILITY IN RAINFALL DROP-SIZE DISTRIBUTIONS OBSERVED AT THE DARWIN ARM SITE

    E-Print Network [OSTI]

    , microwave radiometer, radiosondes, solar and infrared radiometers, etc...provide a means to describe

  7. Observed 20th century desert dust variability: impact on climate and biogeochemistry

    E-Print Network [OSTI]

    2010-01-01

    climate change and desertification in South America, P.precipitation: a possible desertification feedback loop, P.

  8. Mexican drought: an observational modeling and tree ring study of variability and climate change

    E-Print Network [OSTI]

    2009-01-01

    by the state of the tropical Pacific Ocean with the Atlantical. (2005b). 1. POGA (Pacific Ocean-Global Atmosphere): Inoutside of the tropical Pacific Ocean that computes SST

  9. Regional Climate Variability in the Western U.S.: Observed vs. Anticipated

    E-Print Network [OSTI]

    Cycle · ENSO Footprint(s) · Recent Climate Trends · Outlook to Mid-21st Century Range Mgmt. Symposium, Denver, 10 February 10 #12;Average Annual Precipitation for the Western U.S. Based on PRISM OSU/WRCC #12 eruptions, this means more energy input - And higher global temperatures #12;Temperature Widespread warming

  10. Air Observe System

    E-Print Network [OSTI]

    Alexander Bolonkin

    2007-01-10

    This manuscript contains a description and basic principles for observing inaccessible areas using low cost, easily deployed equipment. The basic premise is to suspend a tiny video camera at an altitude of 10 - 200 meters over the area to be surveyed. The TV camera supports at altitude by wind or balloon. The technical challenges regard the means by which the camera is suspended. Such a system may be used by military or police forces or by civil authorities for rescue missions or assessment of natural disasters. The method may be further developed for military applications by integrating the surveillance task with deployment of munitions. Key words: air observer, air suspended system, low altitude video observer.

  11. Search for Variable Stars in the WTS

    E-Print Network [OSTI]

    Pinfield, David J.

    Search for Variable Stars in the WTS Database Hristo Stoev Laboratory of Stellar Astrophysics of January 2010 at LAEX in Madrid, Spain #12;WTS Survey Release 0.1 Search for variable stars in the FOV Narrow down my selection only to one of the detectors ­ 15000 light curves #12;WTS Survey Release 0

  12. 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.

  13. Boosting Search with Variable Elimination. ? Javier Larrosa

    E-Print Network [OSTI]

    Dechter, Rina

    Boosting Search with Variable Elimination. ? Javier Larrosa Dep. Llenguatges i Sistemes Inform#12ElimSearchS;k, a hybrid meta- algorithm that combines search and variable elimination. The param- eter S names from the constraint graph. We also provide experimental evidence that the hybrid algorithm can

  14. Boosting Search with Variable Elimination. ? Javier Larrosa

    E-Print Network [OSTI]

    Dechter, Rina

    Boosting Search with Variable Elimination. ? Javier Larrosa Dep. Llenguatges i Sistemes Inform of variables, reduces the search tree size. In this paper we introduce VarElimSearch(S;k), a hybrid meta the constraint graph. We also provide experimental evidence that the hybrid algorithm can outperform state

  15. Solar Dynamics Observatory/ Extreme Ultraviolet Variability Experiment

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Solar Dynamics Observatory/ EVE Extreme Ultraviolet Variability Experiment Frequently Asked and model solar extreme ultraviolet irradiance variations due to solar flares, solar rotation, and solar and structure of the Sun. What is solar variability? Solar radiation varies on all time scales ranging from

  16. Property Variability Stochastic Multiscale Analysis and Design

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    Property Variability Stochastic Multiscale Analysis and Design of Engine Disks N. Zabaras, B. Wen in nickel-based superalloy turbine disks. Issues: Property variability of turbine disk due to high-dimensional multiscale sources Rolls-Royce RB211- 535 turbofan Nickel-base superalloy turbine disk Superalloy

  17. 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.

  18. Near-Infrared Photometric Variability of Stars Toward the Orion A Molecular Cloud

    E-Print Network [OSTI]

    John M. Carpenter; Lynne A. Hillenbrand; M. F. Skrutskie

    2001-02-26

    We present an analysis of J, H, and K time series photometry obtained with the southern 2MASS telescope over a 0.84 x 6 deg^2 region centered near the Orion Nebula Cluster. These data are used to establish the near-infrared variability properties of pre-main-sequence stars in Orion on time scales of 1-36 days, 2 months, and 2 years. A total of 1235 variable stars are identified, ~93% of which are associated with the Orion A molecular cloud. The variable stars exhibit a diversity of photometric behavior with time, including cyclic fluctuations, aperiodic day-to-day fluctuations, eclipses, slow drifts in brightness over one month, colorless variability, stars that become redder as they fade, and stars that become bluer as they fade. We examine rotational modulation of cool and hot star spots, variable obscuration from an inner circumstellar disk, and changes in the mass accretion rate and other properties in a circumstellar disk as possible origins of the variability. Cool spots can explain the variability characteristics in 56-77% of the stars, while the properties of the photometric fluctuations are more consistent with hot spots or extinction changes in at least 23% of the stars, and with variations in the disk mass accretion rate or inner disk radius in 1% of our sample. However, differences between the details of the observations and the details of variability predicted these models suggest either that another variability mechanism not considered here may be operative, or that the observed variability represents the net results of several of these phenomena. Analysis of the star count data indicates that the ONC is part of a larger area of enhanced stellar surface density which extends over a 0.4 x 2.4 deg^2 (3.4 x 20 pc^2) region containing 2700 stars brighter than K=14. (abridged version)

  19. Global Warming Observations

    E-Print Network [OSTI]

    Schofield, Jeremy

    Global Warming Observations: 1. Global temperature has been gradually rising in recent years #15 in range 8000 12000 nm { CFC's, methane and N 2 O important for global warming even though concentra- tions in concentration of \\greenhouse gases" like CO 2 What determines global temperature? Energy budget of earth: 1

  20. Infrared Colors and Variability of Evolved Stars from COBE DIRBE Data

    E-Print Network [OSTI]

    Beverly J. Smith

    2003-06-20

    For a complete 12 micron flux-limited sample of 207 IRAS sources, we have extracted light curves in seven infrared bands between 1.25 - 60 microns using the database of the DIRBE instrument on the COBE satellite. Using previous infrared surveys, we filtered these light curves to remove datapoints affected by nearby companions. In the time-averaged DIRBE color-color plots, we find clear segregation of semi-regulars, Mira variables, carbon stars, OH/IR stars, and red giants without circumstellar dust and with little or no visual variation. The DIRBE 1.25 - 25 micron colors become progressively redder and the variability in the DIRBE database increases along the oxygen-rich sequence non-dusty slightly varying red giants -> SRb/Lb -> SRa -> Mira -> OH/IR and the carbon-rich SRb/Lb -> Mira sequence. This supports previous assertions that these are evolutionary sequences involving the continued production and ejection of dust. Carbon stars are redder than oxygen-rich stars for the same variability type, except in the F(12)/F(25) ratio. Of the 28 sources in the sample not previous noted to be variable, 18 are clearly variable in the DIRBE data, with amplitudes of variation of ~0.9 magnitudes at 4.9 microns and ~0.6 magnitudes at 12 microns, consistent with them being very dusty Mira-like variables. The light curves of the semi-regular variable L2 Pup are particularly remarkable. The maxima at 1.25, 2.2, and 3.5 microns occur 10 - 20 days before those at 4.9 and 12 microns, and, at 4.9 and 12 microns, another maximum is seen between the two near-infrared maxima.

  1. Multiscale Interactions between Water and Carbon Fluxes and Environmental Variables in A Central U.S. Grassland

    E-Print Network [OSTI]

    Brunsell, Nathaniel A.; Wilson, Cassandra J.

    2013-04-10

    The temporal interactions between water and carbon cycling and the controlling environmental variables are investigated using wavelets and information theory. We used 3.5 years of eddy covariance station observations from an abandoned agricultural...

  2. Quiescent X-ray emission from Cen X-4: a variable thermal component

    E-Print Network [OSTI]

    Cackett, Edward M; Miller, Jon M; Wijnands, Rudy

    2010-01-01

    The nearby neutron star low-mass X-ray binary, Cen X-4, has been in a quiescent state since its last outburst in 1979. Typically, quiescent emission from these objects consists of thermal emission (presumably from the neutron star surface) with an additional hard power-law tail of unknown nature. Variability has been observed during quiescence in Cen X-4 on both timescales as short as hundreds of seconds and as long as years. However, the nature of this variability is still unknown. Early observations seemed to show it was all due to a variable hard X-ray tail. Here, we present new and archival observations that contradict this. The most recent Suzaku observation of Cen X-4 finds it in a historically low state, a factor of 4.4 fainter than the brightest quiescent observation. As the spectrum during the brightest observation was comprised of approximately 60% from the thermal component and 40% from the power-law component, such a large change cannot be explained by just power-law variability. Spectral fits wit...

  3. LATE-TIME SPECTRAL OBSERVATIONS OF THE STRONGLY INTERACTING TYPE Ia SUPERNOVA PTF11kx

    SciTech Connect (OSTI)

    Silverman, Jeffrey M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Nugent, Peter E.; Filippenko, Alexei V.; Cenko, S. Bradley [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gal-Yam, Avishay [Benoziyo Center for Astrophysics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Howell, D. Andrew [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Pan, Yen-Chen; Hook, Isobel M., E-mail: jsilverman@astro.as.utexas.edu [Department of Physics (Astrophysics), University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

    2013-08-01

    PTF11kx was a Type Ia supernova (SN Ia) that showed time-variable absorption features, including saturated Ca II H and K lines that weakened and eventually went into emission. The strength of the emission component of H{alpha} gradually increased, implying that the SN was undergoing significant interaction with its circumstellar medium (CSM). These features, and many others, were blueshifted slightly and showed a P-Cygni profile, likely indicating that the CSM was directly related to, and probably previously ejected by, the progenitor system itself. These and other observations led Dilday et al. to conclude that PTF11kx came from a symbiotic nova progenitor like RS Oph. In this work we extend the spectral coverage of PTF11kx to 124-680 rest-frame days past maximum brightness. The late-time spectra of PTF11kx are dominated by H{alpha} emission (with widths of full width at half-maximum intensity Almost-Equal-To 2000 km s{sup -1}), strong Ca II emission features ({approx}10,000 km s{sup -1} wide), and a blue 'quasi-continuum' due to many overlapping narrow lines of Fe II. Emission from oxygen, He I, and Balmer lines higher than H{alpha} is weak or completely absent at all epochs, leading to large observed H{alpha}/H{beta} intensity ratios. The H{alpha} emission appears to increase in strength with time for {approx}1 yr, but it subsequently decreases significantly along with the Ca II emission. Our latest spectrum also indicates the possibility of newly formed dust in the system as evidenced by a slight decrease in the red wing of H{alpha}. During the same epochs, multiple narrow emission features from the CSM temporally vary in strength. The weakening of the H{alpha} and Ca II emission at late times is possible evidence that the SN ejecta have overtaken the majority of the CSM and agrees with models of other strongly interacting SNe Ia. The varying narrow emission features, on the other hand, may indicate that the CSM is clumpy or consists of multiple thin shells.

  4. Observationally based assessment of polar amplification of global warming

    E-Print Network [OSTI]

    Bhatt, Uma

    Observationally based assessment of polar amplification of global warming Igor V. Polyakov,1) are similar, and do not support the predicted polar amplification of global warming. The possible moderating amplification of global warming. Intrinsic arctic variability obscures long-term changes, limiting our ability

  5. Quantile Regression for Correlated Observations , Lee-Jen Wei2

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    Quantile Regression for Correlated Observations Li Chen1 , Lee-Jen Wei2 , and Michael I. Parzen 1 60637 Abstract In this paper, we consider the problem of regression analysis for data which consist the standard mean regression, we regress various percentiles of each marginal response variable over its

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

    SciTech Connect (OSTI)

    Pražnikar, Jure [Institute Jožef Stefan, Jamova 39, 1000 Ljubljana (Slovenia); University of Primorska, (Slovenia); Turk, Dušan, E-mail: dusan.turk@ijs.si [Institute Jožef 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.

  7. A search for rapid optical variability in radio-quiet quasars

    E-Print Network [OSTI]

    M. Rabbette; B. McBreen; N. Smith; S. Steel

    1998-03-09

    The detection of rapid variability on a time-scale of hours in radio-quiet quasars (RQQSOs) could be a powerful discriminator between starburst, accretion disc and relativistic jet models of these sources. This paper contains an account of a dedicated search for rapid optical variability in RQQSOs. The technique used differential photometry between the RQQSO and stars in the same field of view of the CCD. The 23 RQQSOs that were observed all have high luminosities (-27 1. The total amount of observation time was about 60 hours and these observations are part of an ongoing programme, started in September 1990, to search for rapid variability in RQQSOs. No evidence for short-term variability greater than about 0.1 magnitudes was detected in any of the 23 sources, however long-term variability was recorded for the radio-quiet quasar PG 2112+059. The finding charts are included here because they identify the RQQSO and the reference stars used in the photometry, and hence are available for use by other observers.

  8. Observations of Exoplanet Atmospheres

    E-Print Network [OSTI]

    Crossfield, Ian J M

    2015-01-01

    Detailed characterization of an extrasolar planet's atmosphere provides the best hope for distinguishing the makeup of its outer layers, and the only hope for understanding the interplay between initial composition, chemistry, dynamics & circulation, and disequilibrium processes. In recent years, some areas have seen rapid progress while developments in others have come more slowly and/or have been hotly contested. This article gives an observer's perspective on the current understanding of extrasolar planet atmospheres prior to the considerable advances expected from the next generation of observing facilities. Atmospheric processes of both transiting and directly-imaged planets are discussed, including molecular and atomic abundances, cloud properties, thermal structure, and planetary energy budgets. In the future we can expect a continuing and accelerating stream of new discoveries, which will fuel the ongoing exoplanet revolution for many years to come.

  9. Observable primordial vector modes

    E-Print Network [OSTI]

    Antony Lewis

    2004-06-04

    Primordial vector modes describe vortical fluid perturbations in the early universe. A regular solution exists with constant non-zero radiation vorticities on super-horizon scales. Baryons are tightly coupled to the photons, and the baryon velocity only decays by an order unity factor by recombination, leading to an observable CMB anisotropy signature via the Doppler effect. There is also a large B-mode CMB polarization signal, with significant power on scales larger than l~2000. This B-mode signature is distinct from that expected from tensor modes or gravitational lensing, and makes a primordial vector to scalar mode power ratio ~10^(-6) detectable. Future observations aimed at detecting large scale B-modes from gravitational waves will also be sensitive to regular vector modes at around this level.

  10. The "mean king's problem" with continuous variables

    E-Print Network [OSTI]

    Alonso Botero; Yakir Aharonov

    2007-10-16

    We present the solution to the "mean king's problem" in the continuous variable setting. We show that in this setting, the outcome of a randomly-selected projective measurement of any linear combination of the canonical variables x and p can be ascertained with arbitrary precision. Moreover, we show that the solution is in turn a solution to an associated "conjunctive" version of the problem, unique to continuous variables, where the inference task is to ascertain all the joint outcomes of a simultaneous measurement of any number of linear combinations of x and p.

  11. Numerical study of variable lung ventilation strategies

    E-Print Network [OSTI]

    Yadav, Reena; Hiremath, Kirankumar; Bagler, Ganesh

    2015-01-01

    Mechanical ventilation is used for patients with a variety of lung diseases. Traditionally, ventilators have been designed to monotonously deliver equal sized breaths. While it may seem intuitive that lungs may benefit from unvarying and stable ventilation pressure strategy, recently it has been reported that variable lung ventilation is advantageous. In this study, we analyze the mean tidal volume in response to different `variable ventilation pressure' strategies. We found that uniformly distributed variability in pressure gives the best tidal volume as compared to that of normal, scale- free, log normal and linear distributions.

  12. Analysis of two basic variables of timeout 

    E-Print Network [OSTI]

    Zella, William Francis

    1974-01-01

    ANALYSIS OF TWO BASIC VARIABLES OF TIMEOUT A Thesis WILLIAM FRANCIS ZELLA Submitted to the Graduate College of Texas AaM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August l974 Major Subjects... Psychology ANALYSI QF TWQ BASIC VARIABLES CF TINEQU '. A Thesis V/ILLIAM FRANCIS ZELLA Approved as to s+yle and content bye Chairman of Commi, ee Head of De artment) (Membe Member) Member ABSTRACT Analysis of Two Basic Variables of Timeout. (August...

  13. Observations on European Agriculture. 

    E-Print Network [OSTI]

    Fraps, G. S. (George Stronach)

    1911-01-01

    AS ACKICUL-I-uRAL EXPE RIMENT STATIONS bLLETIN No. 14-1 DECEMBER, 1911 Division of Chemistry Observations on European Agriculture BY G. S. FRAPS, Chemist 0 Postoffice : CULLEGE STATION; TEXAS AUSTIN. TEXAS I AUSTIN PRINTING CO:. PRINTERS... ............................................... and Conclusions 35 [Blank Page in Original Bulletin] rrvations on European Agriculture By C. S. FRAPS ie object of this Bulletin is to present such abservadons on :ulture in Europe as may offer suggestions of value to Texas - :ulturists. The writer...

  14. Dynamics of multi-modes maximum entangled coherent state over amplitude damping channel

    E-Print Network [OSTI]

    A. El Allati; Y. Hassouni; N. Metwally

    2012-02-18

    The dynamics of maximum entangled coherent state travels through an amplitude damping channel is investigated. For small values of the transmissivity rate the travelling state is very fragile to this noise channel, where it suffers from the phase flip error with high probability. The entanglement decays smoothly for larger values of the transmissivity rate and speedily for smaller values of this rate. As the number of modes increases, the travelling state over this noise channel loses its entanglement hastily. The odd and even states vanish at the same value of the field intensity.

  15. Maximum Likelihood method for ultrahigh energy cosmic ray cross correlations with astrophysical sources

    E-Print Network [OSTI]

    Ronnie Jansson; Glennys R. Farrar

    2007-08-20

    We extend the Maximum Likelihood method used by HiRes to study cross correlations between a catalog of candidate astrophysical sources and Ultrahigh Energy Cosmic Rays (UHECRs), to allow for differing source luminosities. Our approach permits individual sources to be ranked according to their likelihood of having emitted the correlated UHECRs. We test both old and new method by simulations for various scenarios. We conclude that there are 9 true correlation between HiRes UHECRs and known BLLacs, with a 6*10^-5 probability of such a correlation arising by chance.

  16. Discrimination of two mixed quantum states with maximum confidence and minimum probability of inconclusive results

    E-Print Network [OSTI]

    Ulrike Herzog

    2009-02-28

    We study an optimized measurement that discriminates two mixed quantum states with maximum confidence for each conclusive result, thereby keeping the overall probability of inconclusive results as small as possible. When the rank of the detection operators associated with the two different conclusive outcomes does not exceed unity we obtain a general solution. As an application, we consider the discrimination of two mixed qubit states. Moreover, for the case of higher-rank detection operators we give a solution for particular states. The relation of the optimized measurement to other discrimination schemes is also discussed.

  17. On the geometrical place formed by the maximum heights of projectile motion with air resistance

    E-Print Network [OSTI]

    Hernández-Saldaña, H

    2010-01-01

    We present an analysis on the geometrical place formed by the set of maxima of the orbits of a projectile launched in a media with linear drag. Such a place is written in term of the Lambert W function in polar coordinates, confirming the special role played by this function in the problem. In order to characterize it, a study of the curvature is presented in two parameterizations, in terms of the launching angle and in the polar one. The angles of maximum curvature are compared with other important angles in the projectile problem.

  18. 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.

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

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan3 November18.5 385.5DryMay-15Decade Year-0Elements) Maximum

  20. Variability of modal parameters measured on the Alamosa Canyon Bridge

    SciTech Connect (OSTI)

    Farrar, C.R.; Doebling, S.W. [Los Alamos National Lab., NM (United States); Cornwell, P.J.; Straser, E.G. [Stanford Univ., CA (United States). J.A. Blume Earthquake Engineering Center

    1996-12-31

    A significant amount of work has been reported in technical literature regarding the use of changes in modal parameters to identify the location and extent of damage in structures. Curiously absent, and critically important to the practical implementation of this work, is an accurate characterization of the natural variability of these modal parameters caused by effects other than damage. To examine this issue, a two-lane, seven-span, composite slab-on-girder bridge near the town of Truth or Consequences in southern New Mexico was tested several times over a period of nine months. Environmental effects common to this location that could potentially produce changes in the measured modal properties include changes in temperature, high winds, and changes to the supporting soil medium. In addition to environmental effects, variabilities in modal testing procedures and data reduction can also cause changes in the identified dynamic properties of the structure. In this paper the natural variability of the frequencies and mode shapes of the Alamosa Canyon bridge that result from changes in time of day when the test was performed, amount of traffic, and environmental conditions will be discussed. Because this bridge has not been in active use throughout the testing period, it is assumed that any change in the observed modal properties are the result of the factors listed above rather than deterioration of the structure itself.

  1. Long term variability of the blazar PKS 2155-304

    E-Print Network [OSTI]

    Chevalier, Jill; Rieger, Frank; Maurin, Gilles; Lenain, Jean-Philippe; Lamanna, Giovanni

    2015-01-01

    Time variability of the photon flux is a known feature of active galactic nuclei (AGN) and in particular of blazars. The high frequency peaked BL Lac (HBL) object PKS 2155-304 is one of the brightest sources in the TeV band and has been monitored regularly with different instruments and in particular with the H.E.S.S. experiment above 200 GeV for more than 11 years. These data together with the observations of other instruments and monitoring programs like SMARTS (optical), Swift-XRT/RXTE/XMM-Newton (X-ray) and Fermi-LAT (100 MeV energy range. Variability studies are made by looking at the lognormality of the light curves and at the fractional root mean square (rms) variability Fvar in several energy bands. Lognormality is found in every energy range and the evolution of Fvar with the energy shows a similar increase both in X-rays and in TeV bands.

  2. Variability in Measured Space Temperatures in 60 Homes

    SciTech Connect (OSTI)

    Roberts, D.; Lay, K.

    2013-03-01

    This report discusses the observed variability in indoor space temperature in a set of 60 homes located in Florida, New York, Oregon, and Washington. Temperature data were collected at 15-minute intervals for an entire year, including living room, master bedroom, and outdoor air temperature (Arena, et. al). The data were examined to establish the average living room temperature for the set of homes for the heating and cooling seasons, the variability of living room temperature depending on climate, and the variability of indoor space temperature within the homes. The accuracy of software-based energy analysis depends on the accuracy of input values. Thermostat set point is one of the most influential inputs for building energy simulation. Several industry standards exist that recommend differing default thermostat settings for heating and cooling seasons. These standards were compared to the values calculated for this analysis. The data examined for this report show that there is a definite difference between the climates and that the data do not agree well with any particular standard.

  3. Analysis of Biomass Feedstock Availability and Variability for the Peace River Region of Alberta, Canada

    SciTech Connect (OSTI)

    Stephen, Jamie [University of British Columbia, Vancouver; Sokhansanj, Shahabaddine [ORNL; Bi, X.T. [University of British Columbia, Vancouver; Sowlati, T. [University of British Columbia, Vancouver; Kloeck, T. [Alberta Agriculture; Townley-Smith, Lawrence [AAFC; Stumborg, Mark [AAFC

    2009-11-01

    Biorefineries or other biomass-dependent facilities require a predictable, dependable feedstock supplied over many years to justify capital investments. Determining inter-year variability in biomass availability is essential to quantifying the feedstock supply risk. Using a geographic information system (GIS) and historic crop yield data, average production was estimated for 10 sites in the Peace River region of Alberta, Canada. Four high-yielding potential sites were investigated for variability over a 20 year time-frame (1980 2000). The range of availability was large, from double the average in maximum years to nothing in minimum years. Biomass availability is a function of grain yield, the biomass to grain ratio, the cropping frequency, and residue retention rate to ensure future crop productivity. Storage strategies must be implemented and alternate feedstock sources identified to supply biomass processing facilities in low-yield years.

  4. Variable reality : interacting with the virtual book

    E-Print Network [OSTI]

    Yang, Hye Soo

    2015-01-01

    This thesis presents Variable Reality, a wearable augmented reality-based system focused on creating a unique on-the-go reading experience that combines the readily accessible nature of digital books with the favorable ...

  5. Variable Speed Pumping for Level Control 

    E-Print Network [OSTI]

    Vasel, M.

    1982-01-01

    analysis, and a brief discussion of variable frequency drive design considerations. Energy savings figures are based upon actual electricity costs at the plant involved. Process duty cycle and energy requirement levels were verified by a wattmeter...

  6. Variable-Rate State Gasoline Taxes

    E-Print Network [OSTI]

    Ang-Olson, Jeffrey; Wachs, Martin; Taylor, Brian D.

    2000-01-01

    J Bradshaw, "SLate ’F~es’ Gasoline Tax So ~t Wdl Rise," TheVarlable-Rate State Gasoline Taxers Jeffrey Ang-Olson MartinVariable-Rate State Gasoline Taxes Jeffrey Ang-Olson

  7. Inserting Group Variables into Fluid Mechanics

    E-Print Network [OSTI]

    R. Jackiw

    2004-10-28

    A fluid, like a quark-gluon plasma, may possess degrees of freedom indexed by a group variable, which retains its identity even in the fluid/continuum description. Conventional Eulerian fluid mechanics is extended to encompass this possibility.

  8. Continuously-Variable Series-Elastic Actuator

    E-Print Network [OSTI]

    Mooney, Luke M.

    Actuator efficiency is an important factor in the design of powered leg prostheses, orthoses, exoskeletons, and legged robots. A continuously-variable series-elastic actuator (CV-SEA) is presented as an efficient actuator ...

  9. 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.

  10. Investigation of Variables Associated with Vaccine Acceptance

    E-Print Network [OSTI]

    Black, Lora L.

    2011-12-31

    Abstract The current study investigated the relationship between the Health Belief Model (HBM) framework, social variables, personality factors, and H1N1 flu vaccine acceptance. Four hundred thirty two undergraduate students completed online...

  11. Exploiting Variable Stiffness in Explosive Movement Tasks

    E-Print Network [OSTI]

    Vijayakumar, Sethu

    with variable physical compliance, our methodology is able to exploit the energy storage capabilities of existing actuators (e.g., by exploiting the energy storage capabilities of such devices) [5]. Due

  12. Variable volume architecture : expanding the boundary

    E-Print Network [OSTI]

    Saheba, Asheshh (Asheshh Mohit), 1972-

    2001-01-01

    Research into the creation of a Variable Volume Architecture is explored through a series of proposals and projects. An argument is established to develop the means and methods of achieving an architecture of transformation. ...

  13. Bounds and phase diagram of efficiency at maximum power for tight-coupling molecular motors

    E-Print Network [OSTI]

    Z. C. Tu

    2013-02-08

    The efficiency at maximum power (EMP) for tight-coupling molecular motors is investigated within the framework of irreversible thermodynamics. It is found that the EMP depends merely on the constitutive relation between the thermodynamic current and force. The motors are classified into four generic types (linear, superlinear, sublinear, and mixed types) according to the characteristics of the constitutive relation, and then the corresponding ranges of the EMP for these four types of molecular motors are obtained. The exact bounds of the EMP are derived and expressed as the explicit functions of the free energy released by the fuel in each motor step. A phase diagram is constructed which clearly shows how the region where the parameters (the load distribution factor and the free energy released by the fuel in each motor step) are located can determine whether the value of the EMP is larger or smaller than 1/2. This phase diagram reveals that motors using ATP as fuel under physiological conditions can work at maximum power with higher efficiency ($>1/2$) for a small load distribution factor ($<0.1$).

  14. Bit Commitment with Quantum Continuous Variables

    E-Print Network [OSTI]

    Vallette, Bruno

    protocol -Basic Unit 9 A B 1,0 1,0 B Unveil Phase 1,0 A 1,0 B 1,0 A 0 0 22' 1,0 22' 1,0 CommitBit Commitment with Quantum Continuous Variables Aikaterini Mandilara* 1 Paris 11 Paris 7 #12;Bit Commitment with Quantum Continuous Variables (a) with entanglement (b) or without 2 (a) A. Mandilara and N

  15. Fluctuations of fragment observables

    E-Print Network [OSTI]

    F. Gulminelli; M. D'Agostino

    2006-11-09

    This contribution presents a review of our present theoretical as well as experimental knowledge of different fluctuation observables relevant to nuclear multifragmentation. The possible connection between the presence of a fluctuation peak and the occurrence of a phase transition or a critical phenomenon is critically analyzed. Many different phenomena can lead both to the creation and to the suppression of a fluctuation peak. In particular, the role of constraints due to conservation laws and to data sorting is shown to be essential. From the experimental point of view, a comparison of the available fragmentation data reveals that there is a good agreement between different data sets of basic fluctuation observables, if the fragmenting source is of comparable size. This compatibility suggests that the fragmentation process is largely independent of the reaction mechanism (central versus peripheral collisions, symmetric versus asymmetric systems, light ions versus heavy ion induced reactions). Configurational energy fluctuations, that may give important information on the heat capacity of the fragmenting system at the freeze out stage, are not fully compatible among different data sets and require further analysis to properly account for Coulomb effects and secondary decays. Some basic theoretical questions, concerning the interplay between the dynamics of the collision and the fragmentation process, and the cluster definition in dense and hot media, are still open and are addressed at the end of the paper. A comparison with realistic models and/or a quantitative analysis of the fluctuation properties will be needed to clarify in the next future the nature of the transition observed from compound nucleus evaporation to multi-fragment production.

  16. ARM Observations Projected

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsicloudden Documentation Data Management Facility PlotsProductsObservations Projected

  17. Interannual Variation of the Surface Temperature of Tropical Forests from Satellite Observations 

    E-Print Network [OSTI]

    Gao, Huilin; Zhang, Shuai; Fu, Rong; Li, Wenhong; Dickinson, Robert E.

    2015-01-01

    and afternoon observations from passive microwave remote sensing facilitate the investigation of the interannual changes of LST anomalies on a diurnal basis. As a result of the variability of cloud cover and the corresponding reduction of solar radiation...

  18. Cataclysmic variables in the SUPERBLINK proper motion survey

    SciTech Connect (OSTI)

    Skinner, Julie N.; Thorstensen, John R.; Lépine, Sébastien

    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.

  19. 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.

  20. Joint H-alpha and X-Ray Observations of Massive X-Ray Binaries. III. The Be X-ray Binaries HDE 245770 = A 0535+26 and X Persei

    E-Print Network [OSTI]

    E. D. Grundstrom; T. S. Boyajian; C. Finch; D. R. Gies; W. Huang; M. V. McSwain; D. P. O'Brien; R. L. Riddle; M. L. Trippe; S. J. Williams; D. W. Wingert; R. A. Zaballa

    2007-02-12

    We present results from an H-alpha monitoring campaign of the Be X-ray binary systems HDE 245770 = A 0535+26 and X Per. We use the H-alpha equivalent widths together with adopted values of the Be star effective temperature, disk inclination, and disk outer boundary to determine the half-maximum emission radius of the disk as a function of time. The observations of HDE 245770 document the rapid spectral variability that apparently accompanied the regeneration of a new circumstellar disk. This disk grew rapidly during the years 1998 - 2000, but then slowed in growth in subsequent years. The outer disk radius is probably truncated by resonances between the disk gas and neutron star orbital periods. Two recent X-ray outbursts appear to coincide with the largest disk half-maximum emission radius attained over the last decade. Our observations of X Per indicate that its circumstellar disk has recently grown to near record proportions, and concurrently the system has dramatically increased in X-ray flux, presumably the result of enhanced mass accretion from the disk. We find that the H-alpha half-maximum emission radius of the disk surrounding X Per reached a size about six times larger than the stellar radius, a value, however, that is well below the minimum separation between the Be star and neutron star. We suggest that spiral arms excited by tidal interaction at periastron may help lift disk gas out to radii where accretion by the neutron star companion becomes more effective.

  1. Photometry of Variable Stars from THU-NAOC Transient Survey I: The First 2 Years

    E-Print Network [OSTI]

    Yao, Xinyu; Wang, Xiaofeng; Zhang, Tianmeng; Chen, Juncheng; Yuan, Wenlong; Mo, Jun; Li, Wenxiong; Jin, Zhiping; Wu, Xuefeng; Nie, JunDan; Zhou, Xu

    2015-01-01

    In this paper, we report the detections of stellar variabilities from the first 2-year observations of sky area of about 1300 square degrees from the Tsinghua University-NAOC Transient Survey (TNTS). A total of 1237 variable stars (including 299 new ones) were detected with brightness = 0.1 mag on a timescale from a few hours to few hundred days. Among such detections, we tentatively identified 661 RR Lyrae stars, 431 binaries, 72 Semiregular pulsators, 29 Mira stars, 11 slow irregular variables, 11 RS Canum Venaticorum stars, 7 Gamma Doradus stars, 5 long period variables, 3 W Virginis stars, 3 Delta Scuti stars, 2 Anomalous Cepheids, 1 Cepheid, and 1 nove-like star based on their time-series variability index Js and their phased diagrams. Moreover, we found that 14 RR Lyrae stars show the Blazhko effect and 67 contact eclipsing binaries exhibit the O'Connell effect. Since the period and amplitude of light variations of RR Lyrae variables depend on their chemical compositions, their photometric observations ...

  2. 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.

  3. OH Maser Observations of Planetary Nebulae Precursors

    E-Print Network [OSTI]

    R. M. Deacon; J. M. Chapman; A. J. Green

    2004-06-08

    We present OH maser observations at 1612, 1665, 1667, and 1720 MHz for 86 post-asymptotic giant branch (post-AGB) stars selected from a survey of 1612 MHz maser sources in the Galactic Plane. The observations were taken with the Parkes Telescope and the Australia Telescope Compact Array between 2002 September and 2003 August. Post-AGB stars are the precursors to planetary nebulae, the diverse morphological range of which is unexplained. The maser observations were taken to investigate the onset and incidence of wind asymmetries during the post-AGB phase. We re-detected all 86 sources at 1612 MHz while 27 sources were detected at 1665 and 45 at 1667 MHz. One source was re-detected at 1720 MHz. We present a classification scheme for the maser profiles and show that 25% of sources in our sample are likely to have asymmetric or bipolar outflows. From a comparison of the maser and far-infrared properties we find that there is a likely trend in the shape of the maser profiles with some sources evolving from double-peaked to irregular to fully bipolar profiles. A subset of higher-mass sources stand out as having almost no mainline emission and mostly double-peaked profiles. At least 25% of sources in the sample are variable at one or more of the frequencies observed. We also confirm a previously-noted 1667 MHz overshoot phenomenon.

  4. Observations of Accreting Pulsars

    E-Print Network [OSTI]

    Lars Bildsten; Deepto Chakrabarty; John Chiu; Mark H. Finger; Danny T. Koh; Robert W. Nelson; Thomas A. Prince; Bradley C. Rubin; D. Matthew Scott; Mark Stollberg; Brian A. Vaughan; Colleen A. Wilson; Robert B. Wilson

    1997-07-22

    We summarize five years of continuous monitoring of accretion-powered pulsars with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. Our 20-70 keV observations have determined or refined the orbital parameters of 13 binaries, discovered 5 new transient accreting pulsars, measured the pulsed flux history during outbursts of 12 transients (GRO J1744-28, 4U 0115+634, GRO J1750-27, GS 0834-430, 2S 1417-624, GRO J1948+32, EXO 2030+375, GRO J1008-57, A 0535+26, GRO J2058+42, 4U 1145-619 and A 1118-616), and also measured the accretion torque history of during outbursts of 6 of those transients whose orbital parameters were also known. We have also continuously measured the pulsed flux and spin frequency for eight persistently accreting pulsars (Her X-1, Cen X-3, Vela X-1, OAO 1657-415, GX 301-2, 4U 1626-67, 4U 1538-52, and GX 1+4). Because of their continuity and uniformity over a long baseline, BATSE observations have provided new insights into the long-term behavior of accreting magnetic stars. We have found that all accreting pulsars show stochastic variations in their spin frequencies and luminosities, including those displaying secular spin-up or spin-down on long time scales, blurring the conventional distinction between disk-fed and wind-fed binaries. Pulsed flux and accretion torque are strongly correlated in outbursts of transient accreting pulsars, but uncorrelated, or even anticorrelated, in persistent sources.

  5. Review of Structures in the Energy Dependence of Hadronic Observables

    E-Print Network [OSTI]

    C. Blume

    2006-11-02

    The energy dependence of various hadronic observables is reviewed. The study of their evolution from AGS over SPS to the highest RHIC energy reveals interesting features, which might locate a possible onset of deconfinement. These observables include transverse spectra of different particle types and their total multiplicities, as well as elliptic flow. In this context especially the observation of a maximum of the strangeness to pion ratio is of particular interest, since on one hand it has been predicted as a signal for the onset of deconfinement but on the other hand also statistical model calculations exhibit qualitatively similar structures. The sharpness of these features is however not reproduced by hadronic scenarios. The significance of these structures will be discussed in this contribution. Other observables, such as radius parameters from Bose-Einstein correlations, on the other hand do not exhibit any structure in their energy dependence.

  6. World-line observables and clocks in General Relativity

    E-Print Network [OSTI]

    Hossein Farajollahi

    2005-11-20

    A proposal for the issue of time and observables in any parameterized theory such as general relativity is addressed. Introduction of a gauge potential 3-form A in the theory of relativity enables us to define a gauge-invariant quantity which can be used by observers as a clock to measure the passage of time. This dynamical variable increases monotonically and continuously along a world line. Then we define world line observables to be any covariantly defined quantity obtained from the field configurations on any such causal past with dynamical time T.

  7. Statistical properties of multi-epoch spectral variability of SDSS stripe 82 quasars

    SciTech Connect (OSTI)

    Kokubo, Mitsuru; Morokuma, Tomoki; Minezaki, Takeo; Doi, Mamoru [Institute of Astronomy, School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Kawaguchi, Toshihiro [Department of Physics and Information Science, Yamaguchi University, Yamaguchi, Yamaguchi 753-8512 (Japan); Sameshima, Hiroaki [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 252-5210 (Japan); Koshida, Shintaro, E-mail: mkokubo@ioa.s.u-tokyo.ac.jp [Center of Astro Engineering and Department of Electrical Engineering, Pontificia Universidad Catolica de Chile, Av. Vicuña Mackenna 4860, Santiago (Chile)

    2014-03-01

    We investigate the UV-optical (longward of Ly? 1216 Å) spectral variability of nearly 9000 quasars (0 < z < 4) using multi-epoch photometric data within the SDSS Stripe 82 region. The regression slope in the flux-flux space of a quasar light curve directly measures the color of the flux difference spectrum, then the spectral shape of the flux difference spectra can be derived by taking a careful look at the redshift dependence of the regression slopes. First, we confirm that the observed quasar spectrum becomes bluer when the quasar becomes brighter. We infer the spectral index of the composite difference spectrum as ?{sub ?}{sup dif}?+1/3 (in the form of f{sub ?}??{sup ?{sub ?}}), which is significantly bluer than that of the composite spectrum ?{sub ?}{sup com}??0.5. We also show that the continuum variability cannot be explained by accretion disk models with varying mass accretion rates. Second, we examine the effects of broad emission line variability on the color-redshift space. The variability of the 'Small Blue Bump' is extensively discussed. We show that the low-ionization lines of Mg II and Fe II are less variable compared to Balmer emission lines and high-ionization lines, and the Balmer continuum is the dominant variable source around ?3000 Å. These results are compared with previous studies, and the physical mechanisms of the variability of the continuum and emission lines are discussed.

  8. UV variability and accretion dynamics in the young open cluster NGC 2264

    E-Print Network [OSTI]

    Venuti, Laura; Irwin, Jonathan; Stauffer, John; Hillenbrand, Lynne; Rebull, Luisa; Cody, Ann Marie; Alencar, Silvia; Micela, Giuseppina; Flaccomio, Ettore; Peres, Giovanni

    2015-01-01

    We explore UV and optical variability signatures for several hundred members of NGC 2264 (3 Myr). We performed simultaneous u- and r-band monitoring over two full weeks with CFHT/MegaCam. About 750 young stars are probed; 40% of them are accreting. Statistically distinct variability properties are observed for accreting and non-accreting cluster members. The accretors exhibit a significantly higher level of variability than the non-accretors, especially in the UV. The amount of u-band variability correlates statistically with UV excess in disk-bearing objects, which suggests that accretion and star-disk interaction are the main sources of variability. Cool magnetic spots, several hundred degrees colder than the photosphere and covering from 5 to 30% of the stellar surface, appear to be the leading factor of variability for the non-accreting stars. In contrast, accretion spots, a few thousand degrees hotter than the photosphere and covering a few percent of the stellar surface, best reproduce the variability o...

  9. Cloud speed impact on solar variability scaling â?? Application to the wavelet variability model

    E-Print Network [OSTI]

    Lave, Matthew; Kleissl, Jan

    2013-01-01

    index: Analysis and statistics. Solar Energy. 81, 195-206.Proc. of International Solar Energy World Congress, Kassel,irradiance variability. Solar Energy. 85, 1343-1353. Perez,

  10. Cloud speed impact on solar variability scaling â?? Application to the wavelet variability model

    E-Print Network [OSTI]

    Lave, Matthew; Kleissl, Jan

    2013-01-01

    Kleissl, J. , 2013. Deriving cloud velocity from an array ofCloud Speed Impact on Solar Variability Scaling -this work, we determine from cloud speeds. Cloud simulator

  11. Bayesian and maximum entropy methods for fusion diagnostic measurements with compact neutron spectrometers

    SciTech Connect (OSTI)

    Reginatto, Marcel; Zimbal, Andreas [Physikalisch-Technische Bundesanstalt, 38116 Braunschweig (Germany)

    2008-02-15

    In applications of neutron spectrometry to fusion diagnostics, it is advantageous to use methods of data analysis which can extract information from the spectrum that is directly related to the parameters of interest that describe the plasma. We present here methods of data analysis which were developed with this goal in mind, and which were applied to spectrometric measurements made with an organic liquid scintillation detector (type NE213). In our approach, we combine Bayesian parameter estimation methods and unfolding methods based on the maximum entropy principle. This two-step method allows us to optimize the analysis of the data depending on the type of information that we want to extract from the measurements. To illustrate these methods, we analyze neutron measurements made at the PTB accelerator under controlled conditions, using accelerator-produced neutron beams. Although the methods have been chosen with a specific application in mind, they are general enough to be useful for many other types of measurements.

  12. Combustion Process in a Spark Ignition Engine: Analysis of Cyclic Maximum Pressure and Peak Pressure Angle

    E-Print Network [OSTI]

    G. Litak; T. Kaminski; J. Czarnigowski; A. K. Sen; M. Wendeker

    2006-11-29

    In this paper we analyze the cycle-to-cycle variations of maximum pressure $p_{max}$ and peak pressure angle $\\alpha_{pmax}$ in a four-cylinder spark ignition engine. We examine the experimental time series of $p_{max}$ and $\\alpha_{pmax}$ for three different spark advance angles. Using standard statistical techniques such as return maps and histograms we show that depending on the spark advance angle, there are significant differences in the fluctuations of $p_{max}$ and $\\alpha_{pmax}$. We also calculate the multiscale entropy of the various time series to estimate the effect of randomness in these fluctuations. Finally, we explain how the information on both $p_{max}$ and $\\alpha_{pmax}$ can be used to develop optimal strategies for controlling the combustion process and improving engine performance.

  13. 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.

  14. Lyapunov exponent and natural invariant density determination of chaotic maps: An iterative maximum entropy ansatz

    E-Print Network [OSTI]

    Parthapratim Biswas; H. Shimoyama; L. R. Mead

    2009-10-23

    We apply the maximum entropy principle to construct the natural invariant density and Lyapunov exponent of one-dimensional chaotic maps. Using a novel function reconstruction technique that is based on the solution of Hausdorff moment problem via maximizing Shannon entropy, we estimate the invariant density and the Lyapunov exponent of nonlinear maps in one-dimension from a knowledge of finite number of moments. The accuracy and the stability of the algorithm are illustrated by comparing our results to a number of nonlinear maps for which the exact analytical results are available. Furthermore, we also consider a very complex example for which no exact analytical result for invariant density is available. A comparison of our results to those available in the literature is also discussed.

  15. Detailed analysis of an endoreversible fuel cell : Maximum power and optimal operating temperature determination

    E-Print Network [OSTI]

    A. Vaudrey; P. Baucour; F. Lanzetta; R. Glises

    2010-08-30

    Producing useful electrical work in consuming chemical energy, the fuel cell have to reject heat to its surrounding. However, as it occurs for any other type of engine, this thermal energy cannot be exchanged in an isothermal way in finite time through finite areas. As it was already done for various types of systems, we study the fuel cell within the finite time thermodynamics framework and define an endoreversible fuel cell. Considering different types of heat transfer laws, we obtain an optimal value of the operating temperature, corresponding to a maximum produced power. This analysis is a first step of a thermodynamical approach of design of thermal management devices, taking into account performances of the whole system.

  16. Detailed analysis of an endoreversible fuel cell : Maximum power and optimal operating temperature determination

    E-Print Network [OSTI]

    Vaudrey, A; Lanzetta, F; Glises, R

    2009-01-01

    Producing useful electrical work in consuming chemical energy, the fuel cell have to reject heat to its surrounding. However, as it occurs for any other type of engine, this thermal energy cannot be exchanged in an isothermal way in finite time through finite areas. As it was already done for various types of systems, we study the fuel cell within the finite time thermodynamics framework and define an endoreversible fuel cell. Considering different types of heat transfer laws, we obtain an optimal value of the operating temperature, corresponding to a maximum produced power. This analysis is a first step of a thermodynamical approach of design of thermal management devices, taking into account performances of the whole system.

  17. VARIABILITY OF DISK EMISSION IN PRE-MAIN SEQUENCE AND RELATED STARS. III. EXPLORING STRUCTURAL CHANGES IN THE PRE-TRANSITIONAL DISK IN HD 169142

    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 HD 169142 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 10 yr. 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 HD 169142 using Monte-Carlo radiative transfer simulation software to explore the conditions and perhaps signs of planetary formation in our collection of 24 yr 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 7 mm 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.

  18. Software Enabled Virtually Variable Displacement Pumps -Theoretical and Experimental Studies

    E-Print Network [OSTI]

    Li, Perry Y.

    Software Enabled Virtually Variable Displacement Pumps - Theoretical and Experimental Studies the functional equivalent of a variable displacement pump. This approach combines a fixed displacement pump valve control, without many of the shortcomings of commercially available variable displacement pumps

  19. Arc Reversals in Hybrid Bayesian Networks with Deterministic Variables

    E-Print Network [OSTI]

    Cinicioglu, Esma N.; Shenoy, Prakash P.

    2009-05-01

    This article discusses arc reversals in hybrid Bayesian networks with deterministic variables. Hybrid Bayesian networks contain a mix of discrete and continuous chance variables. In a Bayesian network representation, a continuous chance variable...

  20. The use of 'race' as a variable in biomedical research

    E-Print Network [OSTI]

    Efstathiou, Sophia

    2009-01-01

    be used as a variable in biomedical research but mainly toRace’ as a Variable in Biomedical Research A dissertationRace’ as a Variable in Biomedical Research…………. Manifest,

  1. 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...

  2. 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.

  3. Kepler and the long-period variables

    SciTech Connect (OSTI)

    Hartig, Erich; Lebzelter, Thomas [University of Vienna, Department of Astrophysics, Türkenschanzstrasse 17, A-1180 Vienna (Austria); Cash, Jennifer [Department of Biological and Physical Sciences, South Carolina State University, P.O. Box 7024, Orangeburg, SC 29117 (United States); Hinkle, Kenneth H.; Mighell, Kenneth J. [National Optical Astronomy Observatories, P.O. Box 26732, Tucson, AZ 85726 (United States); Walter, Donald K., E-mail: erich.hartig@univie.ac.at, E-mail: thomas.lebzelter@univie.ac.at, E-mail: jcash@physics.scsu.edu, E-mail: hinkle@noao.edu, E-mail: mighell@noao.edu, E-mail: dkw@physics.scsu.edu [Department of Biological and Physical Sciences, South Carolina State University, P.O. Box 7296, Orangeburg, SC 29117 (United States)

    2014-12-01

    High-precision Kepler photometry is used to explore the details of asymptotic giant branch (AGB) light curves. Since AGB variability has a typical timescale on the order of a year, we discuss at length the removal of long-term trends and quarterly changes in Kepler data. Photometry for a small sample of nine semi-regular (SR) AGB stars is examined using a 30 minute cadence over a period of 45 months. While undergoing long-period variations of many magnitudes, the light curves are shown to be smooth at the millimagnitude level over much shorter time intervals. No flares or other rapid events were detected on a sub-day timescale. The shortest AGB period detected is on the order of 100 days. All the SR variables in our sample are shown to have multiple modes. This is always the first overtone, typically combined with the fundamental. A second common characteristic of SR variables is shown to be the simultaneous excitation of multiple closely separated periods for the same overtone mode. Approximately half the sample had a much longer variation in the light curve, likely a long secondary period (LSP). The light curves were all well represented by a combination of sinusoids. However, the properties of the sinusoids are time variable, with irregular variations present at low levels. No non-radial pulsations were detected. It is argued that the LSP variation seen in many SR variables is intrinsic to the star and linked to multiple mode pulsation.

  4. Physically constrained maximum likelihood (PCML) mode filtering and its application as a pre-processing method for underwater acoustic communication

    E-Print Network [OSTI]

    Papp, Joseph C

    2009-01-01

    Mode filtering is most commonly implemented using the sampled mode shape or pseudoinverse algorithms. Buck et al [1] placed these techniques in the context of a broader maximum a posteriori (MAP) framework. However, the ...

  5. ESTIMATE OF SOLAR MAXIMUM USING THE 1-8 Å 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 Å 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.

  6. Integrated CMOS Energy Harvesting Converter with Digital Maximum Power Point Tracking for a Portable Thermophotovoltaic Power Generator

    E-Print Network [OSTI]

    Pilawa-Podgurski, Robert

    This paper presents an integrated maximum power point tracking system for use with a thermophotovoltaic (TPV) portable power generator. The design, implemented in 0.35 ?m CMOS technology, consists of a low-power control ...

  7. Estimate of Solar Maximum using the 1-8 \\AA$\\,$Geostationary Operational Environmental Satellites X-ray Measurements

    E-Print Network [OSTI]

    Winter, L M

    2014-01-01

    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 \\AA$\\,$band from 1986 - 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 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.

  8. 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.

  9. 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.

  10. 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

  11. Performance Analysis of Air-Source Variable Speed Heat Pumps...

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

    Performance Analysis of Air-Source Variable Speed Heat Pumps and Various Electric Water Heating Options Performance Analysis of Air-Source Variable Speed Heat Pumps and Various...

  12. 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...

  13. Radiograph and passive data analysis using mixed variable optimization...

    Office of Scientific and Technical Information (OSTI)

    Patent: Radiograph and passive data analysis using mixed variable optimization Citation Details In-Document Search Title: Radiograph and passive data analysis using mixed variable...

  14. 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...

  15. Ocean color and atmospheric dimethyl sulfide: On their mesoscale variability

    E-Print Network [OSTI]

    Matrai, Patricia A; Balch, William M; Cooper, David J; Saltzman, Eric S

    1993-01-01

    periods of' time, covering mesoscale Campbell, J. W. and W.Dimethyl Sulfide' On Their Mesoscale Variability PATRICIA A.Miami, Miami, Florida The mesoscale variability of dimethyl

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

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

    Compact, electro-hydraulic, variable valve actuation system providing variable lift, timing and duration to enable high efficiency engine combustion control Compact,...

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

    Office of Environmental Management (EM)

    Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture Hydrogen-Assisted Fracture: Materials Testing and Variables Governing Fracture SNL has 40+ years...

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

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

    Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Advanced Variable Speed Air-Source Integrated Heat Pump 2013 Peer Review Emerging Technologies Project for...

  19. Residential Cold Climate Heat Pump with Variable-Speed Technology...

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

    Residential Cold Climate Heat Pump with Variable-Speed Technology Residential Cold Climate Heat Pump with Variable-Speed Technology Purdue prototype system Purdue prototype system...

  20. Simulation of the intraseasonal variability over the Eastern...

    Office of Scientific and Technical Information (OSTI)

    Simulation of the intraseasonal variability over the Eastern Pacific ITCZ in climate models Citation Details In-Document Search Title: Simulation of the intraseasonal variability...

  1. AUTOMATIC VARIABLE VENTILATION CONTROL SYSTEMS BASED ON AIR QUALITY DETECTION

    E-Print Network [OSTI]

    Turiel, Isaac

    2011-01-01

    U"'"'''"'" - e "'~saon Automatic Variable Ventilation1979) LBL~8893 EEB Vent 79-3 Automatic variable ventilationmeasurement capabilities o Automatic operation o Low

  2. Assessing net ecosystem carbon exchange of U S terrestrial ecosystems by integrating eddy covariance flux measurements and satellite observations

    SciTech Connect (OSTI)

    Zhuang, Qianlai [Purdue University; Law, Beverly E. [Oregon State University; Baldocchi, Dennis [University of California, Berkeley; Ma, Siyan [University of California, Berkeley; Chen, Jiquan [University of Toledo, Toledo, OH; Richardson, Andrew [Harvard University; Melillo, Jerry [Marine Biological Laboratory; Davis, Ken J. [Pennsylvania State University; Hollinger, D. [USDA Forest Service; Wharton, Sonia [University of California, Davis; Falk, Matthias [University of California, Davis; Paw, U. Kyaw Tha [University of California, Davis; Oren, Ram [Duke University; Katulk, Gabriel G. [Duke University; Noormets, Asko [North Carolina State University; Fischer, Marc [Lawrence Berkeley National Laboratory (LBNL); Verma, Shashi [University of Nebraska; Suyker, A. E. [University of Nebraska, Lincoln; Cook, David R. [Argonne National Laboratory (ANL); Sun, G. [USDA Forest Service; McNulty, Steven G. [USDA Forest Service; Wofsy, Steve [Harvard University; Bolstad, Paul V [University of Minnesota; Burns, Sean [University of Colorado, Boulder; Monson, Russell K. [University of Colorado, Boulder; Curtis, Peter [Ohio State University, The, Columbus; Drake, Bert G. [Smithsonian Environmental Research Center, Edgewater, MD; Foster, David R. [Harvard University; Gu, Lianhong [ORNL; Hadley, Julian L. [Harvard University; Litvak, Marcy [University of New Mexico, Albuquerque; Martin, Timothy A. [University of Florida, Gainesville; Matamala, Roser [Argonne National Laboratory (ANL); Meyers, Tilden [NOAA, Oak Ridge, TN; Oechel, Walter C. [San Diego State University; Schmid, H. P. [Indiana University; Scott, Russell L. [USDA ARS; Torn, Margaret S. [Lawrence Berkeley National Laboratory (LBNL)

    2011-01-01

    More accurate projections of future carbon dioxide concentrations in the atmosphere and associated climate change depend on improved scientific understanding of the terrestrial carbon cycle. Despite the consensus that U.S. terrestrial ecosystems provide a carbon sink, the size, distribution, and interannual variability of this sink remain uncertain. Here we report a terrestrial carbon sink in the conterminous U.S. at 0.63 pg C yr 1 with the majority of the sink in regions dominated by evergreen and deciduous forests and savannas. This estimate is based on our continuous estimates of net ecosystem carbon exchange (NEE) with high spatial (1 km) and temporal (8-day) resolutions derived from NEE measurements from eddy covariance flux towers and wall-to-wall satellite observations from Moderate Resolution Imaging Spectroradiometer (MODIS). We find that the U.S. terrestrial ecosystems could offset a maximum of 40% of the fossil-fuel carbon emissions. Our results show that the U.S. terrestrial carbon sink varied between 0.51 and 0.70 pg C yr 1 over the period 2001 2006. The dominant sources of interannual variation of the carbon sink included extreme climate events and disturbances. Droughts in 2002 and 2006 reduced the U.S. carbon sink by 20% relative to a normal year. Disturbances including wildfires and hurricanes reduced carbon uptake or resulted in carbon release at regional scales. Our results provide an alternative, independent, and novel constraint to the U.S. terrestrial carbon sink.

  3. 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.

  4. Pearle's Hidden-Variable Model Revisited

    E-Print Network [OSTI]

    Richard D. Gill

    2015-05-19

    Pearle (1970) gave an example of a local hidden variables model which exactly reproduced the singlet correlations of quantum theory, through the device of data-rejection: particles can fail to be detected in a way which depends on the hidden variables carried by the particles and on the measurement settings. If the experimenter computes correlations between measurement outcomes of particle pairs for which both particles are detected, he is actually looking at a subsample of particle pairs, determined by interaction involving both measurement settings and the hidden variables carried in the particles. We correct a mistake in Pearle's formulas (a normalization error) and more importantly show that the model is more simple than first appears. We illustrate with visualisations of the model and with a small simulation experiment, with code in the statistical programming language R included in the paper. Open problems are discussed.

  5. 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.

  6. Using Feedforward Neural Networks and Forward Selection of Input Variables for an Ergonomics Data

    E-Print Network [OSTI]

    Kaber, David B.

    Using Feedforward Neural Networks and Forward Selection of Input Variables for an Ergonomics Data-gradient algorithm to develop an FNN. This article presents an incremental step in the use of FNNs for ergonomics enhancing the effectiveness of the use of neural networks when observations are missing from ergonomics

  7. Statistical maps of small-scale electric field variability in the high-latitude ionosphere

    E-Print Network [OSTI]

    Shepherd, Simon

    and the solar wind. The ionospheric electric fields, which are associated with plasma drifts, inject energy characterizing the dependence of high-latitude electric fields on solar wind or geomagnetic conditions, many factors that impact the observed small-scale electric field variability. In general, Southern Hemisphere

  8. Ancillary Statistics In a parametric model f (y; ) for a random variable

    E-Print Network [OSTI]

    Reid, Nancy

    Ancillary Statistics In a parametric model f (y; ) for a random variable or vector Y, a statistic A = a(Y) is ancillary for if the distribution of A does not depend on . As a very simple example, if Y is determined randomly, rather than being fixed in advance, then A = number of observations in Y is an ancillary

  9. Variable pressure power cycle and control system

    DOE Patents [OSTI]

    Goldsberry, Fred L. (Spring, TX)

    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.

  10. 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.

  11. 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.

  12. X-ray Observations of Mrk 231

    E-Print Network [OSTI]

    T. J. Turner

    1998-08-10

    This paper presents new X-ray observations of Mrk 231, an active galaxy of particular interest due to its large infrared luminosity and the presence of several blueshifted broad absorption line (BAL) systems, a phenomenon observed in a small fraction of QSOs. A ROSAT HRI image of Mrk 231 is presented, this shows an extended region of soft X-ray emission, covering several tens of kpc, consistent with the extent of the host galaxy. An ASCA observation of Mrk 231 is also presented. Hard X-rays are detected but the data show no significant variability in X-ray flux. The hard X-ray continuum is heavily attenuated and X-ray column estimates range from ~ 2 x 10^{22} - 10^{23} cm^{-2} depending on whether the material is assumed to be neutral or ionized, and on the model assumed for the extended X-ray component. These ASCA data provide only the second hard X-ray spectrum of a BAL AGN presented to date. The broad-band spectral-energy-distribution of the source is discussed. While Mrk 231 is X-ray weak compared to Seyfert 1 galaxies, it has an optical-to-X-ray spectrum typical of a QSO.

  13. Swift observations of GRB050904: the most distant cosmic explosion ever observed

    E-Print Network [OSTI]

    G. Cusumano; V. Mangano; G. Chincarini; A. Panaitescu; D. N. Burrows; V. La Parola; T. Sakamoto; S. Campana; T. Mineo; G. Tagliaferri; L. Angelini; S. D. Barthelemy; A. P. Beardmore; P. T. Boyd; L. Cominsky; C. Gronwall; E. E. Fenimore; N. Gehrels; P. Giommi; M. Goad; K. Hurley; S. Immler; J. A. Kennea; K. O. Mason; F. Marshall; P. Meszaros; J. A. Nousek; J. P. Osborne; D. M. Palmer; P. W. A. Roming; A. Wells; N. E. White; B. Zhang

    2006-11-08

    Swift discovered the high redshift (z=6.29) GRB050904 with the Burst Alert Telescope (BAT) and began observing with its narrow field instruments 161 s after the burst onset. This gamma-ray burst is the most distant cosmic explosion ever observed. Because of its high redshift, the X-ray Telescope (XRT) and BAT simultaneous observations provide 4 orders of magnitude of spectral coverage (0.2-150 keV; 1.4-1090 keV in the source rest frame) at a very early source-frame time (22 s). GRB050904 was a long, multi-peaked, bright GRB with strong variability during its entire evolution. The light curve observed by the XRT is characterized by the presence of a long flaring activity lasting up to 1-2 hours after the burst onset in the burst rest frame, with no evidence of a smooth power-law decay following the prompt emission as seen in other GRBs. However, the BAT tail extrapolated to the XRT band joins the XRT early light curve and the overall behavior resembles that of a very long GRB prompt. The spectral energy distribution softens with time, with the photon index decreasing from -1.2 during the BAT observation to -1.9 at the end of the XRT observation. The dips of the late X-ray flares may be consistent with an underlying X-ray emission arising from the forward shock and with the properties of the optical afterglow reported by Tagliaferri et al. (2005b). We interpret the BAT and XRT data as a single continuous observation of the prompt emission from a very long GRB. The peculiarities observed in GRB050904 could be due to its origin within one of the first star-forming regions in the Universe; very low metallicities of the progenitor at these epochs may provide an explanation.

  14. A VARIABILITY AND LOCALIZATION STUDY OF THE GALACTIC CENTER GAMMA-RAY SOURCE 3EG J17462851

    E-Print Network [OSTI]

    Pohl, Martin Karl Wilhelm

    A VARIABILITY AND LOCALIZATION STUDY OF THE GALACTIC CENTER GAMMA-RAY SOURCE 3EG J1746�2851 M. Pohl and localization of 3EG J1746�2851 based on EGRET data of the observing periods 1­4. Using corrections for known is observed. Source 3EG J1746�2851 is displaced from the exact Galactic center toward positive Galactic

  15. Group Work: Global warming & natural variability

    E-Print Network [OSTI]

    Allan, Richard P.

    Group Work: Global warming & natural variability Left: Global annual temperature departure from://skepticalscience.com/foster-and-rahmstorf-measure-global-warming-signal.html 2013 2012 2011 #12;: 1963-1964, 1982-83, 1991-93 1. How do these events affect the global annual temperature and can you

  16. Variable Light-Cone Theory of Gravity

    E-Print Network [OSTI]

    I. T. Drummond

    1999-08-20

    We show how to reformulate Variable Speed of Light Theories (VSLT) in a covariant fashion as Variable Light-Cone Theories (VLCT) by introducing two vierbein bundles each associated with a distinct metric. The basic gravitational action relates to one bundle while matter propagates relative to the other in a conventional way. The variability of the speed of light is represented by the variability of the matter light-cone relative to the gravitational light-cone. The two bundles are related locally by an element M, of SL(4,R). The dynamics of the field M is that of a SL(4,R)-sigma model gauged with respect to local (orthochronous) Lorentz transformations on each of the bundles. Only the ``massless'' version of the model with a single new coupling, F, that has the same dimensions as Newton's constant $G_N$, is considered in this paper. When F vanishes the theory reduces to standard General Relativity. We verify that the modified Bianchi identities of the model are consistent with the standard conservation law for the matter energy-momentum tensor in its own background metric. The implications of the model for some simple applications are examined, the Newtonian limit, the flat FRW universe and the spherically symmetric static solution.

  17. 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.

  18. TimeVariable Photo-Evaporation of

    E-Print Network [OSTI]

    Throop, Henry

    TimeVariable Photo-Evaporation of Protoplanetary Disks Henry Throop (SwRI) John Bally (U. Colorado) #12;Takeaway: Photo-evaporation alters the disk structure in essentially unpredictable ways, because for disks formed at the same time in the same cluster. #12;30 Doradus: 100+ O/B stars Photo

  19. TimeVariable Photo-Evaporation of

    E-Print Network [OSTI]

    Throop, Henry

    TimeVariable Photo-Evaporation of Protoplanetary Disks Henry Throop (PSI) DDA Meeting Mt. Hood clusters. #12;Work we have done involves ... ­ UV photo-evaporation from massive stars ­ Interaction; Moeckel & Throop 2009; Throop & Bally 2010; Pichardo et al 2010; Throop 2011. #12;Photo

  20. 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 criteria—a 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 sky—Galactic 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.

  1. EXPERIMENTAL CONTROL OF VARIABLE CAM TIMING ACTUATORS

    E-Print Network [OSTI]

    . This dilution of the mixture in the cylinder re- duces HC and NOx feedgas emissions. Neverthe- less, retarding al., 1998). Table 1 illus- trates the sought after NOx emission reduction when the Variable Cam conditions (1500rpm, 30Nm). NOx pollutant emissions are lowered by retarding the cam timing. ically

  2. Model solution State variable model: differential equation

    E-Print Network [OSTI]

    Limburg, Karin E.

    2/26/2014 1 Model solution State variable model: differential equation Models a rate of change equation General solution: the antiderivative Particular solution: require initial and boundary conditions up the general solution to a differential equation in a book Solve for initial and boundary

  3. CLIMATE VARIABILITY, CLIMATE CHANGE, AND WESTERN

    E-Print Network [OSTI]

    Keeton, William S.

    CHAPTER 13 CLIMATE VARIABILITY, CLIMATE CHANGE, AND WESTERN WILDFIRE WITH IMPLICATIONS FOR THE URBAN­WILDLAND INTERFACE William S. Keeton, Philip W. Mote and Jerry F. Franklin ABSTRACT Climate change hazards by the warmer, drier summers projected for much of the western U.S. by climate models would

  4. 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.

  5. Optical Variability of Infrared Power Law-Selected Galaxies & X-ray Sources in the GOODS-South Field

    E-Print Network [OSTI]

    Alison Klesman; Vicki Sarajedini

    2007-05-07

    We investigate the use of optical variability to identify and study Active Galactic Nuclei (AGN) in the GOODS-South field. A sample of 22 mid-infrared power law sources and 102 X-ray sources with optical counterparts in the HST ACS images were selected. Each object is classified with a variability significance value related to the standard deviation of its magnitude in five epochs separated by 45-day intervals. The variability significance is compared to the optical, mid-IR, and X-ray properties of the sources. We find that 26% of all AGN candidates (either X-ray- or mid-IR-selected) are optical variables. The fraction of optical variables increases to 51% when considering sources with soft X-ray band ratios. For the mid-IR AGN candidates which have multiwavelength SEDs, we find optical variability for 64% of those classified with SEDs like Broad Line AGNs. While mostly unobscured AGN appear to have the most significant optical variability, some of the more obscured AGNs are also observed as variables. In particular, we find two mid-IR power law-selected AGN candidates without X-ray emission that display optical variability, confirming their AGN nature.

  6. Water/Icy Super-Earths: Giant Impacts and Maximum Water Content

    E-Print Network [OSTI]

    Marcus, Robert A; Stewart, Sarah T; Hernquist, Lars

    2010-01-01

    Water-rich super-Earth exoplanets are expected to be common. We explore the effect of late giant impacts on the final bulk abundance of water in such planets. We present the results from smoothed particle hydrodynamics simulations of impacts between differentiated water(ice)-rock planets with masses between 0.5 and 5 M_Earth and projectile to target mass ratios from 1:1 to 1:4. We find that giant impacts between bodies of similar composition never decrease the bulk density of the target planet. If the commonly assumed maximum water fraction of 75wt% for bodies forming beyond the snow line is correct, giant impacts between similar composition bodies cannot serve as a mechanism for increasing the water fraction. Target planets either accrete materials in the same proportion, leaving the water fraction unchanged, or lose material from the water mantle, decreasing the water fraction. The criteria for catastrophic disruption of water-rock planets are similar to those found in previous work on super-Earths of terre...

  7. 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

  8. Parametric study on maximum transportable distance and cost for thermal energy transportation using various coolants

    SciTech Connect (OSTI)

    Su-Jong Yoon; Piyush Sabharwall

    2014-07-01

    The operation temperature of advanced nuclear reactors is generally higher than commercial light water reactors and thermal energy from advanced nuclear reactor can be used for various purposes such as district heating, desalination, hydrogen production and other process heat applications, etc. The process heat industry/facilities will be located outside the nuclear island due to safety measures. This thermal energy from the reactor has to be transported a fair distance. In this study, analytical analysis was conducted to identify the maximum distance that thermal energy could be transported using various coolants such as molten-salts, helium and water by varying the pipe diameter and mass flow rate. The cost required to transport each coolant was also analyzed. The coolants analyzed are molten salts (such as: KClMgCl2, LiF-NaF-KF (FLiNaK) and KF-ZrF4), helium and water. Fluoride salts are superior because of better heat transport characteristics but chloride salts are most economical for higher temperature transportation purposes. For lower temperature water is a possible alternative when compared with He, because low pressure He requires higher pumping power which makes the process very inefficient and economically not viable for both low and high temperature application.

  9. Nonlinear oscillations of compact stars in the vicinity of the maximum mass configuration

    E-Print Network [OSTI]

    Alessandro Brillante; Igor Mishustin

    2015-07-17

    We solve the dynamical GR equations for the spherically symmetric evolution of compact stars in the vicinity of the maximum mass, for which instability sets in according to linear perturbation theory. The calculations are done with the analytical Zeldovich-like EOS P=a(rho-rho_0) and with the TM1 parametrisation of the RMF model. The initial configurations for the dynamical calculations are represented by spherical stars with equilibrium density profile, which are perturbed by either (i) an artificially added inward velocity field proportional to the radial coordinate, or (ii) a rarefaction corresponding to a static and expanded star. These configurations are evolved using a one-dimensional GR hydro code for ideal and barotropic fluids. Depending on the initial conditions we obtain either stable oscillations or the collapse to a black hole. The minimal amplitude of the perturbation, needed to trigger gravitational collapse is evaluated. The approximate independence of this energy on the type of perturbation is pointed out. At the threshold we find type I critical behaviour for all stellar models considered and discuss the dependence of the time scaling exponent on the baryon mass and EOS.

  10. Photometric Stellar Variability in the Galactic Center

    E-Print Network [OSTI]

    M. Rafelski; A. M. Ghez; S. D. Hornstein; J. R. Lu; M. Morris

    2007-01-04

    We report the results of a diffraction-limited, photometric variability study of the central 5"x5" of the Galaxy conducted over the past 10 years using speckle imaging techniques on the W. M. Keck I 10 m telescope. Within our limiting magnitude of mK < 16 mag for images made from a single night of data, we find a minimum of 15 K[2.2 micron]-band variable stars out of 131 monitored stars. The only periodic source in our sample is the previously identified variable IRS 16SW, for which we measure an orbital period of 19.448 +- 0.002 days. In contrast to recent results, our data on IRS 16SW show an asymmetric phased light curve with a much steeper fall-time than rise-time, which may be due to tidal deformations caused by the proximity of the stars in their orbits. We also identify a possible wind colliding binary (IRS 29N) based on its photometric variation over a few year time-scale which is likely due to episodic dust production. None of the 4 LBV candidates in our sample show the characteristic large increase or decrease in luminosity, however, our time baseline is too short to rule them out as LBVs. Among the remaining variable stars, the majority are early-type stars and three are possibly variable due to line of sight extinction variations. For the 7 OB stars at the center of our field of view that have well-determined 3-dimensional orbits, we see no evidence of flares or dimming of their light, which limits the possibility of a cold, geometrically-thin inactive accretion disk around the supermassive black hole, Sgr A*.

  11. GEOCHEMICAL MODELING OF F AREA SEEPAGE BASIN COMPOSITION AND VARIABILITY

    SciTech Connect (OSTI)

    Millings, M.; Denham, M.; Looney, B.

    2012-05-08

    From the 1950s through 1989, the F Area Seepage Basins at the Savannah River Site (SRS) received low level radioactive wastes resulting from processing nuclear materials. Discharges of process wastes to the F Area Seepage Basins followed by subsequent mixing processes within the basins and eventual infiltration into the subsurface resulted in contamination of the underlying vadose zone and downgradient groundwater. For simulating contaminant behavior and subsurface transport, a quantitative understanding of the interrelated discharge-mixing-infiltration system along with the resulting chemistry of fluids entering the subsurface is needed. An example of this need emerged as the F Area Seepage Basins was selected as a key case study demonstration site for the Advanced Simulation Capability for Environmental Management (ASCEM) Program. This modeling evaluation explored the importance of the wide variability in bulk wastewater chemistry as it propagated through the basins. The results are intended to generally improve and refine the conceptualization of infiltration of chemical wastes from seepage basins receiving variable waste streams and to specifically support the ASCEM case study model for the F Area Seepage Basins. Specific goals of this work included: (1) develop a technically-based 'charge-balanced' nominal source term chemistry for water infiltrating into the subsurface during basin operations, (2) estimate the nature of short term and long term variability in infiltrating water to support scenario development for uncertainty quantification (i.e., UQ analysis), (3) identify key geochemical factors that control overall basin water chemistry and the projected variability/stability, and (4) link wastewater chemistry to the subsurface based on monitoring well data. Results from this study provide data and understanding that can be used in further modeling efforts of the F Area groundwater plume. As identified in this study, key geochemical factors affecting basin chemistry and variability included: (1) the nature or chemistry of the waste streams, (2) the open system of the basins, and (3) duration of discharge of the waste stream types. Mixing models of the archetype waste streams indicated that the overall basin system would likely remain acidic much of the time. Only an extended periods of predominantly alkaline waste discharge (e.g., >70% alkaline waste) would dramatically alter the average pH of wastewater entering the basins. Short term and long term variability were evaluated by performing multiple stepwise modeling runs to calculate the oscillation of bulk chemistry in the basins in response to short term variations in waste stream chemistry. Short term (1/2 month and 1 month) oscillations in the waste stream types only affected the chemistry in Basin 1; little variation was observed in Basin 2 and 3. As the largest basin, Basin 3 is considered the primary source to the groundwater. Modeling showed that the fluctuation in chemistry of the waste streams is not directly representative of the source term to the groundwater (i.e. Basin 3). The sequence of receiving basins and the large volume of water in Basin 3 'smooth' or nullify the short term variability in waste stream composition. As part of this study, a technically-based 'charge-balanced' nominal source term chemistry was developed for Basin 3 for a narrow range of pH (2.7 to 3.4). An example is also provided of how these data could be used to quantify uncertainty over the long term variations in waste stream chemistry and hence, Basin 3 chemistry.

  12. Impact of Variable Valve Timing on Low Temperature Combustion

    Broader source: Energy.gov [DOE]

    Documents effects of variable valve actuation in implementing low temperature combustion in production engine platform.

  13. Anomalous transport and observable average in the standard map

    E-Print Network [OSTI]

    Lydia Bouchara; Ouerdia Ourrad; Sandro Vaienti; Xavier Leoncini

    2015-09-02

    The distribution of finite time observable averages and transport in low dimensional Hamiltonian systems is studied. Finite time observable average distributions are computed, from which an exponent $\\alpha$ characteristic of how the maximum of the distributions scales with time is extracted. To link this exponent to transport properties, the characteristic exponent $\\mu(q)$ of the time evolution of the different moments of order $q$ related to transport are computed. As a testbed for our study the standard map is used. The stochasticity parameter $K$ is chosen so that either phase space is mixed with a chaotic sea and islands of stability or with only a chaotic sea. Our observations lead to a proposition of a law relating the slope in $q=0$ of the function $\\mu(q)$ with the exponent $\\alpha$.

  14. Multi-band optical variability studies of BL Lacertae

    E-Print Network [OSTI]

    Agarwal, Aditi

    2015-01-01

    We monitored BL Lacertae for 13 nights in optical B, V, R, and I bands during October and November 2014 including quasi-simultaneous observations in V and R bands using two optical telescopes in India. We have studied multi-band optical flux variations, colour variation and spectral changes in this blazar. Source was found to be active during the whole monitoring period and showed significant intraday variability on 3 nights in V and R filters while displayed hints of variability on 6 other dates in R passband and on 2 nights in V filter. From the colour-magnitude analysis of the source we found that the spectra of the target gets flatter as it becomes brighter on intra-night timescale. Using discrete correlation technique, we found that intraday light curves in both V and R filters are almost consistent and well correlated with each other. We also generated spectral energy distribution (SED) of the target using the B, V, R, and I data sets for all 13 nights which could help us investigate the physical proces...

  15. The RR Lyrae Variable Population in the Phoenix Dwarf Galaxy

    E-Print Network [OSTI]

    Ordoñez, Antonio J; Sarajedini, Ata

    2014-01-01

    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 $\\langle P_{ab}\\rangle = 0.60 \\pm 0.03$ days and $\\langle P_{c}\\rangle = 0.353 \\pm 0.002$ 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 $\\langle [Fe/H]\\rangle = -1.68 \\pm 0.06$ 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 R...

  16. Time variability of AGN and heating of cooling flows

    E-Print Network [OSTI]

    Carlo Nipoti; James Binney

    2005-05-03

    There is increasing evidence that AGN mechanical feedback is important in the energetics of cooling flows in galaxies and galaxy clusters. We investigate the implications of the variability of AGN mechanical luminosity L_m on observations of cooling flows and radio galaxies in general. It is natural to assume that l=ln(L_m/L_x) is a Gaussian process. Then L_m will be log-normally distributed at fixed cooling luminosity L_x, and the variance in a measure of L_m will increase with the time-resolution of the measure. We test the consistency of these predictions with existing data. These tests hinge on the power spectrum of l(t). Monitoring of Seyfert galaxies combined with estimates of the duty cycle of quasars imply flicker noise spectra, similar to those of microquasars. We combine a sample of sources in cooling flows that have cavities with the assumption that the average mechanical luminosity of the AGN equals L_x. Given that the mechanical luminosities are characterized by flicker noise, we find that their spectral amplitudes lie between the estimated amplitudes of quasars and the measured values for the radio luminosities of microquasars. The model together with the observation that powerful radio galaxies lie within a narrow range in optical luminosity, predicts the luminosity function of radio galaxies, in agreement with observations. Forthcoming radio surveys will test the prediction that the luminosity function turns over at about the smallest luminosities so far probed. [Abridged

  17. Variable Faint Optical Sources Discovered by Comparing POSS and SDSS Catalogs

    E-Print Network [OSTI]

    B. Sesar; D. Svilkovic; Z. Ivezic; R. H. Lupton; J. A. Munn; D. Finkbeiner; W. Steinhardt; R. Siverd; D. E. Johnston; G. R. Knapp; J. E. Gunn; C. Rockosi; D. Schlegel; D. E. Vanden Berk; P. Hall; D. P. Schneider; R. J. Brunner

    2004-03-12

    We present a study of variable faint optical sources discovered by comparing the Sloan Digital Sky Survey (SDSS) and the Palomar Observatory Sky Survey (POSS) catalogs. We use SDSS measurements to photometrically recalibrate several publicly available POSS catalogs; a piecewise recalibration in 100 arcmin2 patches generally results in an improvement of photometric accuracy (rms) by nearly a factor of two, compared to the original data. The POSS I magnitudes can be improved to ~0.15 mag accuracy, and POSS II magnitudes to \\~0.10 mag accuracy. We use the recalibrated catalogs for the ~2,000 deg2 of sky in the SDSS Data Release 1 to construct a catalog of ~60,000 sources variable on time scales 10-50 years. A series of statistical tests based on the morphology of SDSS color-color diagrams, as well as visual comparison of images and comparison with repeated SDSS observations, demonstrate the robustness of the selection methods. We quantify the distribution of variable sources in the SDSS color-color diagrams, and the variability characteristics of quasars. We detect a turn-over in quasar structure function which suggests that the characteristic time scale for quasar variability is of the order one year. The long-term (>1 year) quasar variability decreases with luminosity and rest-frame wavelength similarly to the short-term (<1 year) behavior. We also demonstrate that candidate RR Lyrae stars trace the same halo structures, such as the Sgr dwarf tidal stream, that were discovered using repeated SDSS observations. We utilize the POSS-SDSS selected candidates to constrain the halo structure in the parts of sky for which repeated SDSS observations do not exist. (abridged)

  18. Physics 343 Observational Radio Astronomy

    E-Print Network [OSTI]

    Baker, Andrew J.

    is spending this week in Cape Town, South Africa, where he is helping lead the first facetoface meeting is fair game. Previous years: "Current and Future Radio Astronomy Projects" "The Search: measuring a telecope's beam #2: calibrating a telescope's response; measuring solar variability #3

  19. The Search for Cosmological Black Holes: A Surface Brightness Variability Test

    E-Print Network [OSTI]

    Geraint F. Lewis; Rodrigo A. Ibata

    2000-04-04

    Recently it has been suggested that the majority of dark matter in the universe resides in the form of Jupiter mass black holes distributed cosmologically. This population makes itself apparent by microlensing high redshift quasars and introducing pronounced variability into their observed light curves. While several arguments dismissing this hypothesis have been presented, a conclusive observational test is, alas, sadly lacking. In this paper we investigate the effect of a cosmologically distributed population of microlensing masses on galaxies at low to intermediate redshift. The magnification of bright stars in these galaxies leads to small, but observable, fluctuations in their surface brightness. The variability time scale for Jupiter-mass lensing objects is of the order of a few months and this population may be detected through a future space-based monitoring campaign of a field containing $z \\sim 0.5$ galaxies. The monitoring of galactic surface brightness will provide an effective test of the nature of dark matter on cosmological scales.

  20. Physically Observable Cryptography Silvio Micali

    E-Print Network [OSTI]

    Reyzin, Leonid

    Physically Observable Cryptography Silvio Micali Leonid Reyzin November 29, 2003 Abstract.) inherent in the physical execution of any cryptographic algorithm. Such "physical observation attacks mathematically impregnable systems. The great practicality and the inherent availability of physical attacks

  1. 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.

  2. A baseline model for utility bill analysis using both weather and non-weather-related variables

    SciTech Connect (OSTI)

    Sonderegger, R.C. [SRC Systems, Inc., Berkeley, CA (United States)

    1998-12-31

    Many utility bill analyses in the literature rely only on weather-based correlations. While often the dominant cause of seasonal variations in utility consumption, weather variables are far from the only determinant factors. Vacation shutdowns, plug creep, changes in building operation and square footage, and plain poor correlation are all too familiar to the practicing performance contractor. This paper presents a generalized baseline equation, consistent with prior results by others but extended to include other, non-weather-related independent variables. Its compatibility with extensive prior research by others is shown, as well as its application to several types of facilities. The baseline equation, as presented, can accommodate up to five simultaneous independent variables for a maximum of eight free parameters. The use of two additional, empirical degree-day threshold parameters is also discussed. The baseline equation presented here is at the base of a commercial utility accounting software program. All case studies presented to illustrate the development of the baseline equation for each facility are drawn from real-life studies performed by users of this program.

  3. Emerging local warming signals in observational data Irina Mahlstein,1,2

    E-Print Network [OSTI]

    Emerging local warming signals in observational data Irina Mahlstein,1,2 Gabriele Hegerl,3 and Susan Solomon4 Received 19 September 2012; revised 12 October 2012; accepted 15 October 2012; published-to-year variability in local climates impedes the iden- tification of clear changes in observations and human experi

  4. A Stochastic Maximum Principle for a Stochastic Differential Game of a Mean-Field Type

    SciTech Connect (OSTI)

    Hosking, John Joseph Absalom, E-mail: j.j.a.hosking@cma.uio.no [University of Oslo, Centre of Mathematics for Applications (CMA) (Norway)

    2012-12-15

    We construct a stochastic maximum principle (SMP) which provides necessary conditions for the existence of Nash equilibria in a certain form of N-agent stochastic differential game (SDG) of a mean-field type. The information structure considered for the SDG is of a possible asymmetric and partial type. To prove our SMP we take an approach based on spike-variations and adjoint representation techniques, analogous to that of S. Peng (SIAM J. Control Optim. 28(4):966-979, 1990) in the optimal stochastic control context. In our proof we apply adjoint representation procedures at three points. The first-order adjoint processes are defined as solutions to certain mean-field backward stochastic differential equations, and second-order adjoint processes of a first type are defined as solutions to certain backward stochastic differential equations. Second-order adjoint processes of a second type are defined as solutions of certain backward stochastic equations of a type that we introduce in this paper, and which we term conditional mean-field backward stochastic differential equations. From the resulting representations, we show that the terms relating to these second-order adjoint processes of the second type are of an order such that they do not appear in our final SMP equations. A comparable situation exists in an article by R. Buckdahn, B. Djehiche, and J. Li (Appl. Math. Optim. 64(2):197-216, 2011) that constructs a SMP for a mean-field type optimal stochastic control problem; however, the approach we take of using these second-order adjoint processes of a second type to deal with the type of terms that we refer to as the second form of quadratic-type terms represents an alternative to a development, to our setting, of the approach used in their article for their analogous type of term.

  5. A CO(3-2) Survey of Nearby Mira Variables

    E-Print Network [OSTI]

    K. Young

    1995-01-09

    A survey of CO(3-2) emission from optically visible oxygen-rich Mira variable stars within 500 pc of the sun was conducted. A molecular envelope was detected surrounding 36 of the 66 stars examined. Some of these stars have lower outflow velocities than any Miras previously detected in CO. The average terminal velocity of the ejected material was 7.0 km/sec, about half the value found in Miras selected by infrared criteria. None of the stars with spectral types earlier than M 5.5 were detected. The terminal velocity increases as the temperature of the stellar photosphere decreases, as would be expected for a radiation driven wind. Mass loss rates for the detected objects were calculated, and it was found that there is no correlation between the infrared color of a Mira variable, and its mass loss rate. The mass loss rate is correlated with the far infrared luminosity, although a few stars appear to have extensive dust envelopes without any detectable molecular wind. A power-law relationship is found to hold between the mass loss rate and the terminal velocity of the ejected material. This relationship indicates that the dust envelope should be optically thick in the near infrared and visible regions of the spectrum when the outflow velocity is > 17 km/sec. At the low end of the range of outflow velocities seen, the dust drift velocity may be high enough to lead to the destruction of the grains via sputtering. Half of the stars which were detected were re-observed in the CO(4-3) transition. A comparison of the outflow velocities obtained from these observations with those obtained by other investigators at lower frequencies shows no evidence for gradual acceleration of the outer molecular envelope.

  6. The Digital discrimination of neutron and {\\gamma} ray using organic scintillation detector based on wavelet transform modulus maximum

    E-Print Network [OSTI]

    yun, Yang; jun, Yang; xiaoliang, Luo

    2013-01-01

    A novel algorithm for the discrimination of neutron and {\\gamma}-ray with wavelet transform modulus maximum (WTMM) in an organic scintillation has been investigated. Voltage pulses arising from a BC501A organic liquid scintillation detector in a mixed radiation field have been recorded with a fast digital sampling oscilloscope. The performances of most pulse shape discrimination methods in scintillation detection systems using time-domain features of the pulses are affected intensively by noise. However, the WTMM method using frequency-domain features exhibits a strong insensitivity to noise and can be used to discriminate neutron and {\\gamma}-ray events based on their different asymptotic decay trend between the positive modulus maximum curve and the negative modulus maximum curve in the scale-space plane. This technique has been verified by the corresponding mixed-field data assessed by the time-of-flight (TOF) method and the frequency gradient analysis (FGA) method. It is shown that the characterization of...

  7. 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. [Department of Systems and Naval Mechatronics Engineering, National Cheng Kung University, Tainan, Taiwan 701 (China); Pai, F.S. [Department of Electronic Engineering, National University of Tainan (China); Chang, C.C. [Department of Environment and Energy, National University of Tainan (China)

    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)

  8. Swift observations of GRB050904: the most distant cosmic explosion ever observed

    E-Print Network [OSTI]

    Cusumano, G; Chincarini, G; Panaitescu, A; Burrows, D N; La Parola, V; Sakamoto, T; Campana, S; Mineo, T; Tagliaferri, G; Angelini, L; Barthelemy, S D; Beardmore, A P; Boyd, P T; Cominsky, L; Gronwall, C; Fenimore, E E; Gehrels, N; Giommi, P; Goad, M; Hurley, K; Immler, S; Kennea, J A; Mason, K O; Marshall, F; Mészáros, P; Nousek, J A; Osborne, J P; Palmer, D M; Roming, P W A; Wells, A; White, N E; Zhang, B

    2006-01-01

    Swift discovered the high redshift (z=6.29) GRB050904 with the Burst Alert Telescope (BAT) and began observing with its narrow field instruments 161 s after the burst onset. This gamma-ray burst is the most distant cosmic explosion ever observed. Because of its high redshift, the X-ray Telescope (XRT) and BAT simultaneous observations provide 4 orders of magnitude of spectral coverage (0.2-150 keV; 1.4-1090 keV in the source rest frame) at a very early source-frame time (22 s). GRB050904 was a long, multi-peaked, bright GRB with strong variability during its entire evolution. The light curve observed by the XRT is characterized by the presence of a long flaring activity lasting up to 1-2 hours after the burst onset in the burst rest frame, with no evidence of a smooth power-law decay following the prompt emission as seen in other GRBs. However, the BAT tail extrapolated to the XRT band joins the XRT early light curve and the overall behavior resembles that of a very long GRB prompt. The spectral energy distri...

  9. Continuous variable entanglement on a chip

    E-Print Network [OSTI]

    Genta Masada; Kazunori Miyata; Alberto Politi; Toshikazu Hashimoto; Jeremy L. O'Brien; Akira Furusawa

    2015-05-29

    Encoding quantum information in continuous variables (CV)---as the quadrature of electromagnetic fields---is a powerful approach to quantum information science and technology. CV entanglement---light beams in Einstein-Podolsky-Rosen (EPR) states---is a key resource for quantum information protocols; and enables hybridisation between CV and single photon discrete variable (DV) qubit systems. However, CV systems are currently limited by their implementation in free-space optical networks: increased complexity, low loss, high-precision alignment and stability, as well as hybridisation, demand an alternative approach. Here we show an integrated photonic implementation of the key capabilities for CV quantum technologies---generation and characterisation of EPR beams in a photonic chip. Combined with integrated squeezing and non-Gaussian operation, these results open the way to universal quantum information processing with light.

  10. 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.

  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. Thermodynamics in variable speed of light theories

    E-Print Network [OSTI]

    Juan Racker; Pablo Sisterna; Hector Vucetich

    2009-11-30

    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.

  13. First observation of excited states in {sup 182}Pb.

    SciTech Connect (OSTI)

    Jenkins, D. G.; Muikku, M.; Greenlees, P. T.; Hauschild, K.; Helarjutta, K.; Jones, P. M.; Julin, R.; Juutinen, S.; Kankaanpaa, H.; Kelsall, N. S.; Kettunen, H.; Kuusiniemi, P.; Leino, M.; Moore, C. J.; Nieminen, P.; O'Leary, C. D.; Page, R. D.; Rakhila, P.; Reviol, W.; Taylor, M. J.; Uusitalo, J.; Wadsworth, R.; Physics; Univ. of York; Univ. of Jyvaskyla; CEA Saclay; Univ. of Liverpool; Univ. of Tennessee

    2000-01-01

    Excited states in the light lead nucleus, {sup 182}Pb, have been observed for the first time, by means of the recoil-decay tagging technique. A rotational band has been observed which has features in common with bands attributed to a prolate configuration in the heavier neutron deficient lead nuclei, {sup 184-188}Pb. A variable moment of inertia fit to the states in this band suggests that the prolate minimum has risen significantly in energy compared to the next even lead nucleus, {sup 184}Pb. This constitutes firm evidence for the minimization of this configuration with respect to the spherical ground state around N=103.

  14. Observation of inertial energy cascade in interplanetary space plasma

    E-Print Network [OSTI]

    Luca Sorriso-Valvo; Raffaele Marino; Vincenzo Carbone; Fabio Lepreti; Pierluigi Veltri; Alain Noullez; Roberto Bruno; Bruno Bavassano; Ermanno Pietropaolo

    2007-02-09

    We show in this article direct evidence for the presence of an inertial energy cascade, the most characteristic signature of hydromagnetic turbulence (MHD), in the solar wind as observed by the Ulysses spacecraft. After a brief rederivation of the equivalent of Yaglom's law for MHD turbulence, we show that a linear relation is indeed observed for the scaling of mixed third order structure functions involving Els\\"asser variables. This experimental result, confirming the prescription stemming from a theorem for MHD turbulence, firmly establishes the turbulent character of low-frequency velocity and magnetic field fluctuations in the solar wind plasma.

  15. Teleportation using continuous variable quantum cloning machine

    E-Print Network [OSTI]

    Satyabrata Adhikari

    2008-02-15

    We show that an unknown quantum state in phase space can be teleported via three-mode entanglement generated by continuous variable quantum cloning machine (transformation). Further, proceeding with our teleportation protocol we are able to improve the fidelity of teleportation obtained by Loock et.al. [Phys.Rev.Lett. 84, 3482(2000)]. Also we study here the entanglement between the two output copies from cloning machine.

  16. Thermoacoustic tomography with variable sound speed

    E-Print Network [OSTI]

    Plamen Stefanov; Gunther Uhlmann

    2009-05-30

    We study the mathematical model of thermoacoustic tomography in media with a variable speed for a fixed time interval, greater than the diameter of the domain. In case of measurements on the whole boundary, we give an explicit solution in terms of a Neumann series expansion. We give necessary and sufficient conditions for uniqueness and stability when the measurements are taken on a part of the boundary.

  17. Thermoacoustic tomography with variable sound speed

    E-Print Network [OSTI]

    Stefanov, Plamen

    2009-01-01

    We study the mathematical model of thermoacoustic tomography in media with a variable speed for a fixed time interval, greater than the diameter of the domain. In case of measurements on the whole boundary, we give an explicit solution in terms of a Neumann series expansion. We give necessary and sufficient conditions for uniqueness and stability when the measurements are taken on a part of the boundary.

  18. 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.

  19. Variable Compression Ratio Engine | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematics And Statistics » USAJobs Search USAJobs SearchWater-SavingofCode |DepartmentVampire PowerVariable

  20. Variable Reddening and Broad Absorption Lines in the Narrow-line Seyfert 1 Galaxy WPVS 007: an Origin in the Torus

    E-Print Network [OSTI]

    Leighly, Karen M; Grupe, Dirk; Terndrup, Donald M; Komossa, S

    2015-01-01

    We report the discovery of an occultation event in the low-luminosity narrow-line Seyfert 1 galaxy WPVS 007 in 2015 February and March. In concert with longer timescale variability, these observations place strong constraints on the nature and location of the absorbing material. Swift monitoring has revealed a secular decrease since ~2010 accompanied by flattening of the optical and UV photometry that suggests variable reddening. Analysis of four Hubble Space Telescope COS observations since 2010, including a Director's Discretionary time observation during the occultation, shows that the broad-absorption-line velocity offset and the CIV emission-line width both decrease as the reddening increases. The occultation dynamical timescale, the BAL variability dynamical timescale, and the density of the BAL gas show that both the reddening material and the broad-absorption-line gas are consistent with an origin in the torus. These observations can be explained by a scenario in which the torus is clumpy with variabl...