National Library of Energy BETA

Sample records for area probability cluster

  1. Probabilities of octahedral clusters depending on long-range order parameters and composition in nonstoichiometric titanium monoxide TiO{sub y}

    SciTech Connect (OSTI)

    Kostenko, M. G.; Rempel, A. A.

    2012-12-15

    A method for calculating the probabilities of cluster configurations in ordered superstructures of strongly nonstoichiometric compounds depending on the composition and the order parameter is described using the Ti{sub 5}O{sub 5} superstructure of nonstoichiometric titanium monoxide TiO{sub y}. Analytic expressions are derived for the dependences of the probabilities of the main cluster configurations in the Ti{sub 5}O{sub 5} superstructure on the fraction of atomic positions in the titanium and oxygen sublattices and on the long-range order parameter. The probabilities of configurations are calculated for various long-range order parameters taking into account experimental data on the concentration of structural vacancies in the titanium and oxygen sublattices. The dependences of the probabilities of cluster configurations on the short-range order parameter are established from the relations between the superstructure long-range and short-range order parameters.

  2. Attempt to extract the preformation probability of. cap alpha. cluster at the surface of heavy nuclei by means of. cap alpha. -transfer reactions leading to the continuum states

    SciTech Connect (OSTI)

    Xu Shu-wei; Wu Guo-hua; Miao Rong-zhi; Han Fei

    1983-07-01

    The method of parametrization of an EFR-DWBA overlap integral developed by T. Udagawa and T. Tamura et al./sup 1/ is improved. Using the improved method we have fitted the experimental double differential energy spectrum of the /sup 8/Be cluster coming from the reaction /sup 208/Pb(/sup 12/C, /sup 8/Be) /sup 212/Po leading to the continuum states and extracted the preformation probability of the ..cap alpha.. cluster at the surface of the /sup 212/Po nucleus. Within the range of calculation error, the result is in agreement with that extracted from fitting the experimental data of ..cap alpha.. decay.

  3. A Cluster-based Method to Map Urban Area from DMSP/OLS Nightlights

    SciTech Connect (OSTI)

    Zhou, Yuyu; Smith, Steven J.; Elvidge, Christopher; Zhao, Kaiguang; Thomson, Allison M.; Imhoff, Marc L.

    2014-05-05

    Accurate information of urban areas at regional and global scales is important for both the science and policy-making communities. The Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime stable light data (NTL) provide a potential way to map urban area and its dynamics economically and timely. In this study, we developed a cluster-based method to estimate the optimal thresholds and map urban extents from the DMSP/OLS NTL data in five major steps, including data preprocessing, urban cluster segmentation, logistic model development, threshold estimation, and urban extent delineation. Different from previous fixed threshold method with over- and under-estimation issues, in our method the optimal thresholds are estimated based on cluster size and overall nightlight magnitude in the cluster, and they vary with clusters. Two large countries of United States and China with different urbanization patterns were selected to map urban extents using the proposed method. The result indicates that the urbanized area occupies about 2% of total land area in the US ranging from lower than 0.5% to higher than 10% at the state level, and less than 1% in China, ranging from lower than 0.1% to about 5% at the province level with some municipalities as high as 10%. The derived thresholds and urban extents were evaluated using high-resolution land cover data at the cluster and regional levels. It was found that our method can map urban area in both countries efficiently and accurately. Compared to previous threshold techniques, our method reduces the over- and under-estimation issues, when mapping urban extent over a large area. More important, our method shows its potential to map global urban extents and temporal dynamics using the DMSP/OLS NTL data in a timely, cost-effective way.

  4. Constraints on dark matter annihilation in clusters of galaxies with the Fermi large area telescope

    SciTech Connect (OSTI)

    Ackermann, M.; Ajello, M.; Allafort, A.; Bechtol, K.; Blandford, R.D.; Bloom, E.D.; Borgland, A.W.; Bouvier, A.; Buehler, R.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Ballet, J.; Bastieri, D.; Buson, S.; Bonamente, E.; Brandt, T.J.; Bruel, P. E-mail: profumo@scipp.ucsc.edu [Laboratoire Leprince-Ringuet, École polytechnique, CNRS and others

    2010-05-01

    Nearby clusters and groups of galaxies are potentially bright sources of high-energy gamma-ray emission resulting from the pair-annihilation of dark matter particles. However, no significant gamma-ray emission has been detected so far from clusters in the first 11 months of observations with the Fermi Large Area Telescope. We interpret this non-detection in terms of constraints on dark matter particle properties. In particular for leptonic annihilation final states and particle masses greater than ∼ 200 GeV, gamma-ray emission from inverse Compton scattering of CMB photons is expected to dominate the dark matter annihilation signal from clusters, and our gamma-ray limits exclude large regions of the parameter space that would give a good fit to the recent anomalous Pamela and Fermi-LAT electron-positron measurements. We also present constraints on the annihilation of more standard dark matter candidates, such as the lightest neutralino of supersymmetric models. The constraints are particularly strong when including the fact that clusters are known to contain substructure at least on galaxy scales, increasing the expected gamma-ray flux by a factor of ∼ 5 over a smooth-halo assumption. We also explore the effect of uncertainties in cluster dark matter density profiles, finding a systematic uncertainty in the constraints of roughly a factor of two, but similar overall conclusions. In this work, we focus on deriving limits on dark matter models; a more general consideration of the Fermi-LAT data on clusters and clusters as gamma-ray sources is forthcoming.

  5. Mapping the formation areas of giant molybdenum blue clusters: a spectroscopic study

    SciTech Connect (OSTI)

    Botar, Bogdan; Ellern, Arkady; Kogerler, Paul

    2012-05-18

    The self-assembly of soluble molybdenum blue species from simple molybdate solutions has primarily been associated with giant mixed-valent wheel-shaped cluster anions, derived from the {MoV/VI154/176} archetypes, and a {MoV/VI368} lemon-shaped cluster. The combined use of Raman spectroscopy and kinetic precipitation as self-assembly monitoring techniques and single-crystal X-ray diffraction is key to mapping the realm of molybdenum blue species by establishing spherical {MoV/VI102}-type Keplerates as an important giant molybdenum blue-type species. We additionally rationalize the empirical effect of reducing agent concentration on the formation of all three relevant skeletal types: wheel, lemon and spheres. Whereas both wheels and the lemon-shaped {MoV/VI368} cluster are obtained from weakly reduced molybdenum blue solutions, considerably higher reduced solutions lead to {MoV/VI102}-type Keplerates.

  6. THE MASSIVE AND DISTANT CLUSTERS OF WISE SURVEY. II. INITIAL SPECTROSCOPIC CONFIRMATION OF z ? 1 GALAXY CLUSTERS SELECTED FROM 10,000 deg{sup 2}

    SciTech Connect (OSTI)

    Stanford, S. A.; Gonzalez, Anthony H.; Gettings, Daniel P.; Brodwin, Mark; Eisenhardt, Peter R. M.; Stern, Daniel; Wylezalek, Dominika

    2014-08-01

    We present optical and infrared imaging and optical spectroscopy of galaxy clusters which were identified as part of an all-sky search for high-redshift galaxy clusters, the Massive and Distant Clusters of WISE Survey (MaDCoWS). The initial phase of MaDCoWS combined infrared data from the all-sky data release of the Wide-field Infrared Survey Explorer (WISE) with optical data from the Sloan Digital Sky Survey to select probable z ? 1 clusters of galaxies over an area of 10,000 deg{sup 2}. Our spectroscopy confirms 19 new clusters at 0.7 < z < 1.3, half of which are at z > 1, demonstrating the viability of using WISE to identify high-redshift galaxy clusters. The next phase of MaDCoWS will use the greater depth of the AllWISE data release to identify even higher redshift cluster candidates.

  7. Matlab Cluster Ensemble Toolbox

    Energy Science and Technology Software Center (OSTI)

    2009-04-27

    This is a Matlab toolbox for investigating the application of cluster ensembles to data classification, with the objective of improving the accuracy and/or speed of clustering. The toolbox divides the cluster ensemble problem into four areas, providing functionality for each. These include, (1) synthetic data generation, (2) clustering to generate individual data partitions and similarity matrices, (3) consensus function generation and final clustering to generate ensemble data partitioning, and (4) implementation of accuracy metrics. Withmore » regard to data generation, Gaussian data of arbitrary dimension can be generated. The kcenters algorithm can then be used to generate individual data partitions by either, (a) subsampling the data and clustering each subsample, or by (b) randomly initializing the algorithm and generating a clustering for each initialization. In either case an overall similarity matrix can be computed using a consensus function operating on the individual similarity matrices. A final clustering can be performed and performance metrics are provided for evaluation purposes.« less

  8. Field Observation GoAmazon Neutral cluster Air Ion Spectrometer...

    Office of Scientific and Technical Information (OSTI)

    ... In this work, we used novel instrumentation including the neutral cluster and air ion ... Then. we detected what were probably anthropogenic pollution plumes from Manaus. and ...

  9. Northern Colorado Clean Energy Cluster | Open Energy Information

    Open Energy Info (EERE)

    Clean Energy Cluster Jump to: navigation, search Name: Northern Colorado Clean Energy Cluster Place: Denver, Colorado Zip: 80202 Region: Rockies Area Website: www.nccleanenergy.com...

  10. Interference of probabilities in dynamics

    SciTech Connect (OSTI)

    Zak, Michail

    2014-08-15

    A new class of dynamical systems with a preset type of interference of probabilities is introduced. It is obtained from the extension of the Madelung equation by replacing the quantum potential with a specially selected feedback from the Liouville equation. It has been proved that these systems are different from both Newtonian and quantum systems, but they can be useful for modeling spontaneous collective novelty phenomena when emerging outputs are qualitatively different from the weighted sum of individual inputs. Formation of language and fast decision-making process as potential applications of the probability interference is discussed.

  11. Cluster Statistics

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

    Statistics Cluster Statistics Ganglia Ganglia can be used to monitor performance of PDSF nodes... Read More PDSF IO Monitoring This page shows the IO response of the elizas and...

  12. Probability of Liquefaction for H-Area Savannah River Site

    SciTech Connect (OSTI)

    Lee, R.C.

    2000-09-27

    In 1995 WSRC completed the geotechnical assessment for the In-Tank Precipitation Facility and the H-Tank Farm at the Savannah River Site. As part of that assessment, a probabilistic liquefaction evaluation for the Tobacco Road soils was completed.

  13. Cluster generator

    DOE Patents [OSTI]

    Donchev, Todor I.; Petrov, Ivan G.

    2011-05-31

    Described herein is an apparatus and a method for producing atom clusters based on a gas discharge within a hollow cathode. The hollow cathode includes one or more walls. The one or more walls define a sputtering chamber within the hollow cathode and include a material to be sputtered. A hollow anode is positioned at an end of the sputtering chamber, and atom clusters are formed when a gas discharge is generated between the hollow anode and the hollow cathode.

  14. Lectures on probability and statistics

    SciTech Connect (OSTI)

    Yost, G.P.

    1984-09-01

    These notes are based on a set of statistics lectures delivered at Imperial College to the first-year postgraduate students in High Energy Physics. They are designed for the professional experimental scientist. We begin with the fundamentals of probability theory, in which one makes statements about the set of possible outcomes of an experiment, based upon a complete a priori understanding of the experiment. For example, in a roll of a set of (fair) dice, one understands a priori that any given side of each die is equally likely to turn up. From that, we can calculate the probability of any specified outcome. We finish with the inverse problem, statistics. Here, one begins with a set of actual data (e.g., the outcomes of a number of rolls of the dice), and attempts to make inferences about the state of nature which gave those data (e.g., the likelihood of seeing any given side of any given die turn up). This is a much more difficult problem, of course, and one's solutions often turn out to be unsatisfactory in one respect or another.

  15. Bay Area | Open Energy Information

    Open Energy Info (EERE)

    Page Edit History Bay Area Jump to: navigation, search Contents 1 Clean Energy Clusters in the Bay Area 1.1 Products and Services in the Bay Area 1.2 Research and Development...

  16. Rockies Area | Open Energy Information

    Open Energy Info (EERE)

    Rockies Area Jump to: navigation, search Contents 1 Clean Energy Clusters in the Rockies Area 1.1 Products and Services in the Rockies Area 1.2 Research and Development...

  17. Texas Area | Open Energy Information

    Open Energy Info (EERE)

    Area Jump to: navigation, search Contents 1 Clean Energy Clusters in the Texas Area 1.1 Products and Services in the Texas Area 1.2 Research and Development Institutions in the...

  18. Cluster Statistics

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

    Genepool Memory Heatmaps Usage Statistics UGE Scheduler Cycle Time File storage and I/O Data Management Supported Systems FAQ Performance and Optimization Genepool Completed Jobs Genepool Training and Tutorials Websites, databases and cluster services Queues and Scheduling Retired Systems Storage & File Systems Application Performance Data & Analytics Job Logs & Statistics Training & Tutorials Software Policies User Surveys NERSC Users Group Help Staff Blogs Request Repository

  19. THE BLACK HOLE FORMATION PROBABILITY

    SciTech Connect (OSTI)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P {sub BH}(M {sub ZAMS}). Although we find that it is difficult to derive a unique P {sub BH}(M {sub ZAMS}) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P {sub BH}(M {sub ZAMS}) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P {sub BH}(M {sub ZAMS}) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  20. Geographic Resource Map of Frozen Pipe Probabilities

    Broader source: Energy.gov [DOE]

    Presentation slide details a resource map showing the probability of frozen pipes in the geographic United States.

  1. THE EXTENDED VIRGO CLUSTER CATALOG

    SciTech Connect (OSTI)

    Kim, Suk; Rey, Soo-Chang; Lee, Youngdae; Chung, Jiwon; Pak, Mina; Yi, Wonhyeong; Lee, Woong; Jerjen, Helmut; Lisker, Thorsten; Sung, Eon-Chang

    2015-01-01

    We present a new catalog of galaxies in the wider region of the Virgo cluster, based on the Sloan Digital Sky Survey (SDSS) Data Release 7. The Extended Virgo Cluster Catalog (EVCC) covers an area of 725 deg{sup 2} or 60.1 Mpc{sup 2}. It is 5.2 times larger than the footprint of the classical Virgo Cluster Catalog (VCC) and reaches out to 3.5 times the virial radius of the Virgo cluster. We selected 1324 spectroscopically targeted galaxies with radial velocities less than 3000 km s{sup –1}. In addition, 265 galaxies that have been overlooked in the SDSS spectroscopic survey but have available redshifts in the NASA Extragalactic Database are also included. Our selection process secured a total of 1589 galaxies, 676 of which are not included in the VCC. The certain and possible cluster members are defined by means of redshift comparison with a cluster infall model. We employed two independent and complementary galaxy classification schemes: the traditional morphological classification based on the visual inspection of optical images and a characterization of galaxies from their spectroscopic features. SDSS u, g, r, i, and z passband photometry of all EVCC galaxies was performed using Source Extractor. We compare the EVCC galaxies with the VCC in terms of morphology, spatial distribution, and luminosity function. The EVCC defines a comprehensive galaxy sample covering a wider range in galaxy density that is significantly different from the inner region of the Virgo cluster. It will be the foundation for forthcoming galaxy evolution studies in the extended Virgo cluster region, complementing ongoing and planned Virgo cluster surveys at various wavelengths.

  2. Supersonic Bare Metal Cluster Beams. Technical Progress Report, March 16, 1984 - April 1, 1985

    DOE R&D Accomplishments [OSTI]

    Smalley, R. E.

    1985-01-01

    There have been four major areas of concentration for the study of bare metal cluster beams: neutral cluster, chemical reactivity, cold cluster ion source development (both positive and negative), bare cluster ion ICR (ion cyclotron resonance) development, and photofragmentation studies of bare metal cluster ions.

  3. Cluster Compatibility Mode

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

    Cluster Compatibility Mode Cluster Compatibility Mode Edison compute nodes run a stripped-down Linux operating system called Compute Node Linux (CNL). Some standard Linux services,...

  4. Galaxy clustering with photometric surveys using PDF redshift information

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

    Asorey, J.; Carrasco Kind, M.; Sevilla-Noarbe, I.; Brunner, R. J.; Thaler, J.

    2016-03-28

    Here, photometric surveys produce large-area maps of the galaxy distribution, but with less accurate redshift information than is obtained from spectroscopic methods. Modern photometric redshift (photo-z) algorithms use galaxy magnitudes, or colors, that are obtained through multi-band imaging to produce a probability density function (PDF) for each galaxy in the map. We used simulated data to study the effect of using different photo-z estimators to assign galaxies to redshift bins in order to compare their effects on angular clustering and galaxy bias measurements. We found that if we use the entire PDF, rather than a single-point (mean or mode) estimate, the deviations are less biased, especially when using narrow redshift bins. When the redshift bin widths aremore » $$\\Delta z=0.1$$, the use of the entire PDF reduces the typical measurement bias from 5%, when using single point estimates, to 3%.« less

  5. Southern CA Area | Open Energy Information

    Open Energy Info (EERE)

    CA Area Jump to: navigation, search Contents 1 Clean Energy Clusters in the Southern CA Area 1.1 Products and Services in the Southern CA Area 1.2 Research and Development...

  6. Probability-theoretic characteristics of solar batteries

    SciTech Connect (OSTI)

    Lidorenko, N.S.; Asharin, L.N.; Borisova, N.A.; Evdokimov, V.M.; Ryabikov, S.V.

    1980-01-01

    Results are reported for an investigation into the characteristics of solar batteries on the basis of probability theory with the photocells treated as current generators; methods for reducing solar-battery circuit losses are considered.

  7. Probability distribution of the vacuum energy density

    SciTech Connect (OSTI)

    Duplancic, Goran; Stefancic, Hrvoje; Glavan, Drazen

    2010-12-15

    As the vacuum state of a quantum field is not an eigenstate of the Hamiltonian density, the vacuum energy density can be represented as a random variable. We present an analytical calculation of the probability distribution of the vacuum energy density for real and complex massless scalar fields in Minkowski space. The obtained probability distributions are broad and the vacuum expectation value of the Hamiltonian density is not fully representative of the vacuum energy density.

  8. POF-Darts: Geometric adaptive sampling for probability of failure

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

    Ebeida, Mohamed S.; Mitchell, Scott A.; Swiler, Laura P.; Romero, Vicente J.; Rushdi, Ahmad A.

    2016-06-18

    We introduce a novel technique, POF-Darts, to estimate the Probability Of Failure based on random disk-packing in the uncertain parameter space. POF-Darts uses hyperplane sampling to explore the unexplored part of the uncertain space. We use the function evaluation at a sample point to determine whether it belongs to failure or non-failure regions, and surround it with a protection sphere region to avoid clustering. We decompose the domain into Voronoi cells around the function evaluations as seeds and choose the radius of the protection sphere depending on the local Lipschitz continuity. As sampling proceeds, regions uncovered with spheres will shrink,more » improving the estimation accuracy. After exhausting the function evaluation budget, we build a surrogate model using the function evaluations associated with the sample points and estimate the probability of failure by exhaustive sampling of that surrogate. In comparison to other similar methods, our algorithm has the advantages of decoupling the sampling step from the surrogate construction one, the ability to reach target POF values with fewer samples, and the capability of estimating the number and locations of disconnected failure regions, not just the POF value. Furthermore, we present various examples to demonstrate the efficiency of our novel approach.« less

  9. Cluster Bioenergia | Open Energy Information

    Open Energy Info (EERE)

    Cluster Bioenergia Jump to: navigation, search Name: Cluster Bioenergia Place: Mato Grosso, Brazil Product: Mato Grosso-based ethanol project developer company. References: Cluster...

  10. Reassessment of the BWR scram failure probability

    SciTech Connect (OSTI)

    Burns, E.T.

    1989-01-01

    As part of the Severe Accident Policy Statement implementation, the probabilistic quantification of accident sequence frequencies that may lead to core damage is a key element in demonstrating a plant's safety status relative to US Nuclear Regulatory Commission (NRC) staff goals. One of the key quantitative inputs in a boiling water reactor (BWR) probabilistic risk assessment is the probability of a failure to scram. The assessment of this failure probability has been the subject of a long and continuing debate over the adequacy of available data and analytic modeling. This report provides a summary of the status of this debate, including the latest data, and provides a revision to the characterization of the failure probability originally published in NUREG 0460 and the Utility Group on Anticipated Transient Without Scram (ATWS) Petition.

  11. Non-Gaussian Photon Probability Distribution

    SciTech Connect (OSTI)

    Solomon, Benjamin T.

    2010-01-28

    This paper investigates the axiom that the photon's probability distribution is a Gaussian distribution. The Airy disc empirical evidence shows that the best fit, if not exact, distribution is a modified Gamma mGAMMA distribution (whose parameters are alpha = r, betar/sq root(u)) in the plane orthogonal to the motion of the photon. This modified Gamma distribution is then used to reconstruct the probability distributions along the hypotenuse from the pinhole, arc from the pinhole, and a line parallel to photon motion. This reconstruction shows that the photon's probability distribution is not a Gaussian function. However, under certain conditions, the distribution can appear to be Normal, thereby accounting for the success of quantum mechanics. This modified Gamma distribution changes with the shape of objects around it and thus explains how the observer alters the observation. This property therefore places additional constraints to quantum entanglement experiments. This paper shows that photon interaction is a multi-phenomena effect consisting of the probability to interact P{sub i}, the probabilistic function and the ability to interact A{sub i}, the electromagnetic function. Splitting the probability function P{sub i} from the electromagnetic function A{sub i} enables the investigation of the photon behavior from a purely probabilistic P{sub i} perspective. The Probabilistic Interaction Hypothesis is proposed as a consistent method for handling the two different phenomena, the probability function P{sub i} and the ability to interact A{sub i}, thus redefining radiation shielding, stealth or cloaking, and invisibility as different effects of a single phenomenon P{sub i} of the photon probability distribution. Sub wavelength photon behavior is successfully modeled as a multi-phenomena behavior. The Probabilistic Interaction Hypothesis provides a good fit to Otoshi's (1972) microwave shielding, Schurig et al.(2006) microwave cloaking, and Oulton et al.(2008) sub

  12. Electric quadrupole transition probabilities for atomic lithium

    SciTech Connect (OSTI)

    elik, Gltekin; Gke, Yasin; Y?ld?z, Murat

    2014-05-15

    Electric quadrupole transition probabilities for atomic lithium have been calculated using the weakest bound electron potential model theory (WBEPMT). We have employed numerical non-relativistic HartreeFock wavefunctions for expectation values of radii and the necessary energy values have been taken from the compilation at NIST. The results obtained with the present method agree very well with the Coulomb approximation results given by Caves (1975). Moreover, electric quadrupole transition probability values not existing in the literature for some highly excited levels have been obtained using the WBEPMT.

  13. New TRACC Cluster Computer

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

    TRACC Cluster Computer With the addition of a new cluster called Zephyr that was made operational in September of this year (2012), TRACC now offers two clusters to choose from: Zephyr and our original cluster that has now been named Phoenix. Zephyr was acquired from Atipa technologies, and it is a 92-node system with each node having two AMD 16 core, 2.3 GHz, 32 GB processors. See also Computing Resources.

  14. LENSING NOISE IN MILLIMETER-WAVE GALAXY CLUSTER SURVEYS

    SciTech Connect (OSTI)

    Hezaveh, Yashar; Vanderlinde, Keith; Holder, Gilbert; De Haan, Tijmen

    2013-08-01

    We study the effects of gravitational lensing by galaxy clusters of the background of dusty star-forming galaxies (DSFGs) and the cosmic microwave background (CMB), and examine the implications for Sunyaev-Zel'dovich-based (SZ) galaxy cluster surveys. At the locations of galaxy clusters, gravitational lensing modifies the probability distribution of the background flux of the DSFGs as well as the CMB. We find that, in the case of a single-frequency 150 GHz survey, lensing of DSFGs leads both to a slight increase ({approx}10%) in detected cluster number counts (due to a {approx}50% increase in the variance of the DSFG background, and hence an increased Eddington bias) and a rare (occurring in {approx}2% of clusters) 'filling-in' of SZ cluster signals by bright strongly lensed background sources. Lensing of the CMB leads to a {approx}55% reduction in CMB power at the location of massive galaxy clusters in a spatially matched single-frequency filter, leading to a net decrease in detected cluster number counts. We find that the increase in DSFG power and decrease in CMB power due to lensing at cluster locations largely cancel, such that the net effect on cluster number counts for current SZ surveys is subdominant to Poisson errors.

  15. Optimum phase space probabilities from quantum tomography

    SciTech Connect (OSTI)

    Roy, Arunabha S.; Roy, S. M.

    2014-01-15

    We determine a positive normalised phase space probability distribution P with minimum mean square fractional deviation from the Wigner distribution W. The minimum deviation, an invariant under phase space rotations, is a quantitative measure of the quantumness of the state. The positive distribution closest to W will be useful in quantum mechanics and in time frequency analysis. The position-momentum correlations given by the distribution can be tested experimentally in quantum optics.

  16. Microsoft Word - Price Probabilities Supplement.doc

    Gasoline and Diesel Fuel Update (EIA)

    0 1 April 2010 Short-Term Energy Outlook Supplement: Probabilities of Possible Future Prices 1 EIA introduced a monthly analysis of energy price volatility and forecast uncertainty in the October 2009 Short-Term Energy Outlook (STEO). Included in the analysis were charts portraying confidence intervals around the New York Mercantile Exchange (NYMEX) futures prices of West Texas Intermediate (equivalent to light sweet crude oil) and Henry Hub natural gas contracts. The March 2010 STEO added

  17. Computation of neutron fluxes in clusters of fuel pins arranged in hexagonal assemblies (2D and 3D)

    SciTech Connect (OSTI)

    Prabha, H.; Marleau, G.

    2012-07-01

    For computations of fluxes, we have used Carvik's method of collision probabilities. This method requires tracking algorithms. An algorithm to compute tracks (in 2D and 3D) has been developed for seven hexagonal geometries with cluster of fuel pins. This has been implemented in the NXT module of the code DRAGON. The flux distribution in cluster of pins has been computed by using this code. For testing the results, they are compared when possible with the EXCELT module of the code DRAGON. Tracks are plotted in the NXT module by using MATLAB, these plots are also presented here. Results are presented with increasing number of lines to show the convergence of these results. We have numerically computed volumes, surface areas and the percentage errors in these computations. These results show that 2D results converge faster than 3D results. The accuracy on the computation of fluxes up to second decimal is achieved with fewer lines. (authors)

  18. Electron: Cluster interactions

    SciTech Connect (OSTI)

    Scheidemann, A.A.; Kresin, V.V.; Knight, W.D.

    1994-02-01

    Beam depletion spectroscopy has been used to measure absolute total inelastic electron-sodium cluster collision cross sections in the energy range from E {approximately} 0.1 to E {approximately} 6 eV. The investigation focused on the closed shell clusters Na{sub 8}, Na{sub 20}, Na{sub 40}. The measured cross sections show an increase for the lowest collision energies where electron attachment is the primary scattering channel. The electron attachment cross section can be understood in terms of Langevin scattering, connecting this measurement with the polarizability of the cluster. For energies above the dissociation energy the measured electron-cluster cross section is energy independent, thus defining an electron-cluster interaction range. This interaction range increases with the cluster size.

  19. Probability Density Function Method for Langevin Equations with...

    Office of Scientific and Technical Information (OSTI)

    Probability Density Function Method for Langevin Equations with Colored Noise Citation Details In-Document Search Title: Probability Density Function Method for Langevin Equations ...

  20. Clustering versus non-clustering phase synchronizations

    SciTech Connect (OSTI)

    Liu, Shuai; University of Chinese Academy of Sciences, Beijing 100049 ; Zhan, Meng

    2014-03-15

    Clustering phase synchronization (CPS) is a common scenario to the global phase synchronization of coupled dynamical systems. In this work, a novel scenario, the non-clustering phase synchronization (NPS), is reported. It is found that coupled systems do not transit to the global synchronization until a certain sufficiently large coupling is attained, and there is no clustering prior to the global synchronization. To reveal the relationship between CPS and NPS, we further analyze the noise effect on coupled phase oscillators and find that the coupled oscillator system can change from CPS to NPS with the increase of noise intensity or system disorder. These findings are expected to shed light on the mechanism of various intriguing self-organized behaviors in coupled systems.

  1. THE MEMBERSHIP AND DISTANCE OF THE OPEN CLUSTER COLLINDER 419

    SciTech Connect (OSTI)

    Roberts, Lewis C.; Gies, Douglas R.; Parks, J. Robert; Grundstrom, Erika D.; McSwain, M. Virginia; Berger, David H.; Mason, Brian D.; Ten Brummelaar, Theo A.; Turner, Nils H. E-mail: gies@chara.gsu.ed E-mail: erika.grundstrom@vanderbilt.ed E-mail: dberger@sysplan.co E-mail: theo@chara-array.or

    2010-09-15

    The young open cluster Collinder 419 surrounds the massive O star, HD 193322, that is itself a remarkable multiple star system containing at least four components. Here we present a discussion of the cluster distance based upon new spectral classifications of the brighter members, UBV photometry, and an analysis of astrometric and photometric data from the third U. S. Naval Observatory CCD Astrograph Catalog and Two Micron All Sky Survey Catalog. We determine an average cluster reddening of E(B - V) = 0.37 {+-} 0.05 mag and a cluster distance of 741 {+-} 36 pc. The cluster probably contains some very young stars that may include a reddened M3 III star, IRAS 20161+4035.

  2. Muster: Massively Scalable Clustering

    Energy Science and Technology Software Center (OSTI)

    2010-05-20

    Muster is a framework for scalable cluster analysis. It includes implementations of classic K-Medoids partitioning algorithms, as well as infrastructure for making these algorithms run scalably on very large systems. In particular, Muster contains algorithms such as CAPEK (described in reference 1) that are capable of clustering highly distributed data sets in-place on a hundred thousand or more processes.

  3. Cool Cluster Correctly Correlated

    SciTech Connect (OSTI)

    Sergey Aleksandrovich Varganov

    2005-12-17

    Atomic clusters are unique objects, which occupy an intermediate position between atoms and condensed matter systems. For a long time it was thought that physical and chemical properties of atomic dusters monotonically change with increasing size of the cluster from a single atom to a condensed matter system. However, recently it has become clear that many properties of atomic clusters can change drastically with the size of the clusters. Because physical and chemical properties of clusters can be adjusted simply by changing the cluster's size, different applications of atomic clusters were proposed. One example is the catalytic activity of clusters of specific sizes in different chemical reactions. Another example is a potential application of atomic clusters in microelectronics, where their band gaps can be adjusted by simply changing cluster sizes. In recent years significant advances in experimental techniques allow one to synthesize and study atomic clusters of specified sizes. However, the interpretation of the results is often difficult. The theoretical methods are frequently used to help in interpretation of complex experimental data. Most of the theoretical approaches have been based on empirical or semiempirical methods. These methods allow one to study large and small dusters using the same approximations. However, since empirical and semiempirical methods rely on simple models with many parameters, it is often difficult to estimate the quantitative and even qualitative accuracy of the results. On the other hand, because of significant advances in quantum chemical methods and computer capabilities, it is now possible to do high quality ab-initio calculations not only on systems of few atoms but on clusters of practical interest as well. In addition to accurate results for specific clusters, such methods can be used for benchmarking of different empirical and semiempirical approaches. The atomic clusters studied in this work contain from a few atoms to

  4. Document clustering methods, document cluster label disambiguation methods, document clustering apparatuses, and articles of manufacture

    DOE Patents [OSTI]

    Sanfilippo, Antonio; Calapristi, Augustin J.; Crow, Vernon L.; Hetzler, Elizabeth G.; Turner, Alan E.

    2009-12-22

    Document clustering methods, document cluster label disambiguation methods, document clustering apparatuses, and articles of manufacture are described. In one aspect, a document clustering method includes providing a document set comprising a plurality of documents, providing a cluster comprising a subset of the documents of the document set, using a plurality of terms of the documents, providing a cluster label indicative of subject matter content of the documents of the cluster, wherein the cluster label comprises a plurality of word senses, and selecting one of the word senses of the cluster label.

  5. Resource-Efficient Generataion of Linear Cluster States by Linear Optics with postselection

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

    Uskov, Dmitry B; Alsing, Paul; Fanto, Michael; Kaplan, Lev; Kim, R; Szep, Atilla; Smith IV, Amos M

    2015-01-01

    We report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detectionmore » of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2^n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4^m-1.« less

  6. Resource-Efficient Generataion of Linear Cluster States by Linear Optics with postselection

    SciTech Connect (OSTI)

    Uskov, Dmitry B; Alsing, Paul; Fanto, Michael; Kaplan, Lev; Kim, R; Szep, Atilla; Smith IV, Amos M

    2015-01-01

    We report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2^n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4^m-1.

  7. Resource-efficient generation of linear cluster states by linear optics with postselection

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

    Uskov, D. B.; Alsing, P. M.; Fanto, M. L.; Kaplan, L.; Kim, R.; Szep, A.; Smith, A. M.

    2015-01-30

    Here we report on theoretical research in photonic cluster-state computing. Finding optimal schemes of generating non-classical photonic states is of critical importance for this field as physically implementable photon-photon entangling operations are currently limited to measurement-assisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multi-photon cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneousmore » detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dual-rail optical qubits into a linear cluster state is equal to 1/2n-1; an m-tuple of photonic Bell pair states, commonly generated via spontaneous parametric down-conversion, can be fused into a single cluster with the maximal success probability of 1/4m-1.« less

  8. Industry Cluster Development Grant winners

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

    Industry Cluster Development Grant winners Community Connections: Your link to news and ... All Issues submit Industry Cluster Development Grant winners Recipients include Picuris ...

  9. Lectures on probability and statistics. Revision

    SciTech Connect (OSTI)

    Yost, G.P.

    1985-06-01

    These notes are based on a set of statistics lectures delivered at Imperial College to the first-year postgraduate students in High Energy Physics. They are designed for the professional experimental scientist. They begin with the fundamentals of probability theory, in which one makes statements about the set of possible outcomes of an experiment, based upon a complete a priori understanding of the experiment. For example, in a roll of a set of (fair) dice, one understands a priori that any given side of each die is equally likely to turn up. From that, we can calculate the probabilty of any specified outcome. They finish with the inverse problem, statistics. Here, one begins with a set of actual data (e.g., the outcomes of a number of rolls of the dice), and attempts to make inferences about the state of nature which gave those data (e.g., the likelihood of seeing any given side of any given die turn up). This is a much more difficult problem, of course, and one's solutions often turn out to be unsatisfactory in one respect or another. Hopefully, the reader will come away from these notes with a feel for some of the problems and uncertainties involved. Although there are standard approaches, most of the time there is no cut and dried ''best'' solution - ''best'' according to every criterion.

  10. Parametric probability distributions for anomalous change detection

    SciTech Connect (OSTI)

    Theiler, James P; Foy, Bernard R; Wohlberg, Brendt E; Scovel, James C

    2010-01-01

    The problem of anomalous change detection arises when two (or possibly more) images are taken of the same scene, but at different times. The aim is to discount the 'pervasive differences' that occur thoughout the imagery, due to the inevitably different conditions under which the images were taken (caused, for instance, by differences in illumination, atmospheric conditions, sensor calibration, or misregistration), and to focus instead on the 'anomalous changes' that actually take place in the scene. In general, anomalous change detection algorithms attempt to model these normal or pervasive differences, based on data taken directly from the imagery, and then identify as anomalous those pixels for which the model does not hold. For many algorithms, these models are expressed in terms of probability distributions, and there is a class of such algorithms that assume the distributions are Gaussian. By considering a broader class of distributions, however, a new class of anomalous change detection algorithms can be developed. We consider several parametric families of such distributions, derive the associated change detection algorithms, and compare the performance with standard algorithms that are based on Gaussian distributions. We find that it is often possible to significantly outperform these standard algorithms, even using relatively simple non-Gaussian models.

  11. Mantis BT Cluster Support

    Energy Science and Technology Software Center (OSTI)

    2009-06-05

    The software is a modidication to the Mantis BT V1.5 open source application provided by the mantis BT group to support cluster web servers. It also provides various cosmetic modifications used a LLNL.

  12. Dirac GPU Cluster

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

    Dirac Dirac GPU Cluster Current Status: Up NOTICE: Dirac was shut down permanently and retired from service at 17:00 on Friday, December 12, 2014. Dirac was a testbed experimental...

  13. Cluster Compatibility Mode

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

    Some standard Linux services, such as ssh, rsh, nscd, and ldap, are not supported on the ... It provides the standard Linux services needed to run most cluster-based independent ...

  14. WAS THE SUN BORN IN A MASSIVE CLUSTER?

    SciTech Connect (OSTI)

    Dukes, Donald; Krumholz, Mark R.

    2012-07-20

    A number of authors have argued that the Sun must have been born in a cluster of no more than several thousand stars, on the basis that, in a larger cluster, close encounters between the Sun and other stars would have truncated the outer solar system or excited the outer planets into eccentric orbits. However, this dynamical limit is in tension with meteoritic evidence that the solar system was exposed to a nearby supernova during or shortly after its formation; a several-thousand-star cluster is much too small to produce a massive star whose lifetime is short enough to have provided the enrichment. In this paper, we revisit the dynamical limit in the light of improved observations of the properties of young clusters. We use a series of scattering simulations to measure the velocity-dependent cross-section for disruption of the outer solar system by stellar encounters, and use this cross-section to compute the probability of a disruptive encounter as a function of birth cluster properties. We find that, contrary to prior work, the probability of disruption is small regardless of the cluster mass, and that it actually decreases rather than increases with cluster mass. Our results differ from prior work for three main reasons: (1) unlike in most previous work, we compute a velocity-dependent cross-section and properly integrate over the cluster mass-dependent velocity distribution of incoming stars; (2) we recognize that {approx}90% of clusters have lifetimes of a few crossing times, rather than the 10-100 Myr adopted in many earlier models; and (3) following recent observations, we adopt a mass-independent surface density for embedded clusters, rather than a mass-independent radius as assumed many earlier papers. Our results remove the tension between the dynamical limit and the meteoritic evidence, and suggest that the Sun was born in a massive cluster. A corollary to this result is that close encounters in the Sun's birth cluster are highly unlikely to truncate

  15. Evaluation of Proposed Hampton Roads Area Sites for Using Small...

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

    of Potential Locations for Siting Small Modular Reactors near Federal Energy Clusters to Support Federal Clean Energy Goals Identification of Selected Areas to Support ...

  16. Probable new type of reaction mechanism: Double. cap alpha. direct...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; BERYLLIUM 8; CLUSTER MODEL; BISMUTH 209 TARGET; CARBON 12 REACTIONS; MULTI-NUCLEON TRANSFER REACTIONS; ALPHA ...

  17. FUEL ROD CLUSTERS

    DOE Patents [OSTI]

    Schultz, A.B.

    1959-08-01

    A cluster of nuclear fuel rods and a tubular casing therefor through which a coolant flows in heat-exchange contact with the fuel rods is described. The fuel rcds are held in the casing by virtue of the compressive force exerted between longitudinal ribs of the fuel rcds and internal ribs of the casing or the internal surfaces thereof.

  18. Low Probability Tail Event Analysis and Mitigation in BPA Control Area: Task One Report

    SciTech Connect (OSTI)

    Lu, Shuai; Makarov, Yuri V.

    2009-04-01

    This is a report for task one of the tail event analysis project for BPA. Tail event refers to the situation in a power system when unfavorable forecast errors of load and wind are superposed onto fast load and wind ramps, or non-wind generators falling short of scheduled output, the imbalance between generation and load becomes very significant. This type of events occurs infrequently and appears on the tails of the distribution of system power imbalance; therefore, is referred to as tail events. This report analyzes what happened during the Electric Reliability Council of Texas (ERCOT) reliability event on February 26, 2008, which was widely reported because of the involvement of wind generation. The objective is to identify sources of the problem, solutions to it and potential improvements that can be made to the system. Lessons learned from the analysis include the following: (1) Large mismatch between generation and load can be caused by load forecast error, wind forecast error and generation scheduling control error on traditional generators, or a combination of all of the above; (2) The capability of system balancing resources should be evaluated both in capacity (MW) and in ramp rate (MW/min), and be procured accordingly to meet both requirements. The resources need to be able to cover a range corresponding to the variability of load and wind in the system, additional to other uncertainties; (3) Unexpected ramps caused by load and wind can both become the cause leading to serious issues; (4) A look-ahead tool evaluating system balancing requirement during real-time operations and comparing that with available system resources should be very helpful to system operators in predicting the forthcoming of similar events and planning ahead; and (5) Demand response (only load reduction in ERCOT event) can effectively reduce load-generation mismatch and terminate frequency deviation in an emergency situation.

  19. Low Probability Tail Event Analysis and Mitigation in the BPA Control Area

    SciTech Connect (OSTI)

    Lu, Shuai; Brothers, Alan J.; McKinstry, Craig A.; Jin, Shuangshuang; Makarov, Yuri V.

    2010-10-31

    This report investigated the uncertainties with the operations of the power system and their contributions to tail events, especially under high penetration of wind. A Bayesian network model is established to quantify the impact of these uncertainties on system imbalance. The framework is presented for a decision support tool, which can help system operators better estimate the need for balancing reserves and prepare for tail events.

  20. Research Areas

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

    Research Areas Our Vision National User Facilities Research Areas In Focus Global Solutions ⇒ Navigate Section Our Vision National User Facilities Research Areas In Focus Global Solutions Biosciences The Biosciences Area forges multidisciplinary teams to solve national challenges in energy, environment and health issues; and to advance the engineering of biological systems for sustainable manufacturing. Biosciences Area research is coordinated through three divisions and is enabled by Berkeley

  1. Environmental Business Cluster EBC | Open Energy Information

    Open Energy Info (EERE)

    Business Cluster EBC Jump to: navigation, search Name: Environmental Business Cluster (EBC) Place: San Jose, California Zip: CA 95113 Product: The Environmental Business Cluster is...

  2. Environmental Business Cluster | Open Energy Information

    Open Energy Info (EERE)

    Cluster Jump to: navigation, search Logo: Environmental Business Cluster Name: Environmental Business Cluster Address: 2 North First Street, Third Floor Place: San Jose, California...

  3. Method of precisely modifying predetermined surface layers of a workpiece by cluster ion impact therewith

    DOE Patents [OSTI]

    Friedman, L.; Beuhler, R.J.; Matthew, M.W.; Ledbetter, M.

    1984-06-25

    A method of precisely modifying a selected area of a workpiece by producing a beam of charged cluster ions that is narrowly mass selected to a predetermined mean size of cluster ions within a range of 25 to 10/sup 6/ atoms per cluster ion, and accelerated in a beam to a critical velocity. The accelerated beam is used to impact a selected area of an outer surface of the workpiece at a preselected rate of impacts of cluster ions/cm/sup 2//sec in order to effect a precise modification in that selected area of the workpiece.

  4. Method of precisely modifying predetermined surface layers of a workpiece by cluster ion impact therewith

    DOE Patents [OSTI]

    Friedman, Lewis; Buehler, Robert J.; Matthew, Michael W.; Ledbetter, Myron

    1985-01-01

    A method of precisely modifying a selected area of a workpiece by producing a beam of charged cluster ions that is narrowly mass selected to a predetermined mean size of cluster ions within a range of 25 to 10.sup.6 atoms per cluster ion, and accelerated in a beam to a critical velocity. The accelerated beam is used to impact a selected area of an outer surface of the workpiece at a preselected rate of impacts of cluster ions/cm.sup.2 /sec. in order to effect a precise modification in that selected area of the workpiece.

  5. Transition probability from matter-wave soliton to chaos

    SciTech Connect (OSTI)

    Zhu Qianquan; Hai Wenhua; Rong Shiguang

    2009-07-15

    For a Bose-Einstein condensate loaded into a weak traveling optical superlattice, it is demonstrated that under a stochastic initial set and in a given parameter region, the solitonic chaos appears with a certain probability. Effects of the lattice depths and wave vectors on the chaos probability are investigated analytically and numerically and different chaotic regions associated with different chaos probabilities are found. The results suggest a method for weakening or strengthening chaos by modulating the moving superlattice.

  6. Code System to Calculate Pressure Vessel Failure Probabilities.

    Energy Science and Technology Software Center (OSTI)

    2001-03-27

    Version 00 OCTAVIA (Operationally Caused Transients And Vessel Integrity Analysis) calculates the probability of pressure vessel failure from operationally-caused pressure transients which can occur in a pressurized water reactor (PWR). For specified vessel and operating environment characteristics the program computes the failure pressure at which the vessel will fail for different-sized flaws existing in the beltline and the probability of vessel failure per reactor year due to the flaw. The probabilities are summed over themore » various flaw sizes to obtain the total vessel failure probability. Sensitivity studies can be performed to investigate different vessel or operating characteristics in the same computer run.« less

  7. Energy level structure and transition probabilities in the spectra...

    Office of Scientific and Technical Information (OSTI)

    Energy level structure and transition probabilities in the spectra of the trivalent lanthanides in LaFsub 3. Tables, diagrams Citation Details In-Document Search Title: Energy ...

  8. Derivatized gold clusters and antibody-gold cluster conjugates

    DOE Patents [OSTI]

    Hainfeld, J.F.; Furuya, F.R.

    1994-11-01

    Antibody- or antibody fragment-gold cluster conjugates are shown wherein the conjugate size can be as small as 5.0 nm. Methods and reagents are disclosed in which antibodies, Fab' or F(ab')[sub 2] fragments are covalently bound to a stable cluster of gold atoms. The gold clusters may contain 6, 8, 9, 11, 13, 55 or 67 gold atoms in their inner core. The clusters may also contain radioactive gold. The antibody-cluster conjugates are useful in electron microscopy applications as well as in clinical applications that include imaging, diagnosis and therapy. 7 figs.

  9. Derivatized gold clusters and antibody-gold cluster conjugates

    DOE Patents [OSTI]

    Hainfeld, James F.; Furuya, Frederic R.

    1994-11-01

    Antibody- or antibody fragment-gold cluster conjugates are shown wherein the conjugate size can be as small as 5.0 nm. Methods and reagents are disclosed in which antibodies, Fab' or F(ab').sub.2 fragments thereof are covalently bound to a stable cluster of gold atoms. The gold clusters may contain 6, 8, 9, 11, 13, 55 or 67 gold atoms in their inner core. The clusters may also contain radioactive gold. The antibody-cluster conjugates are useful in electron microscopy applications as well as in clinical applications that include imaging, diagnosis and therapy.

  10. Connecting Remote Clusters with ATM

    SciTech Connect (OSTI)

    Hu, T.C.; Wyckoff, P.S.

    1998-10-01

    Sandia's entry into utilizing clusters of networked workstations is called Computational Plant or CPlant for short. The design of CPlant uses Ethernet to boot the individual nodes, Myrinet to communicate within a node cluster, and ATM to connect between remote clusters. This SAND document covers the work done to enable the use of ATM on the CPlant nodes in the Fall of 1997.

  11. Probable new type of reaction mechanism: Double. cap alpha. direct transfer process

    SciTech Connect (OSTI)

    Xu Shu-wei; Wu Guo-hua; Miao Rong-zhi; Han Fei

    1983-10-01

    It is assumed that /sup 8/Be consists of two ..cap alpha.. particles which are close to each other in configuration space. A spectroscopic density of /sup 8/Be cluster in the residue nuclei is then obtained, which is proportional to the square of the preformation probability of ..cap alpha.. particle at nuclear surface. Using the improved method of parametrization of EFR-DWBA overlap integral,/sup 1//sup en-dash//sup 2/ we calculate the double differential energy spectra and angular distributions of ..cap alpha.. particles for the reactions /sup 209/Bi (/sup 12/C, ..cap alpha..) /sup 217/Fr and extract the preformation probability of ..cap alpha.. particle at the surface of /sup 217/Fr nuclei from fitting the experimental data. The agreement within the range of calculation error between the preformation probabilities extracted from transfer reactions and ..cap alpha.. decay suggests that the reaction /sup 209/Bi(/sup 12/C, ..cap alpha..) /sup 217/Fr may be explained as a double ..cap alpha.. direct transfer process.

  12. Matlab Cluster Ensemble Toolbox v. 1.0

    Energy Science and Technology Software Center (OSTI)

    2009-04-27

    This is a Matlab toolbox for investigating the application of cluster ensembles to data classification, with the objective of improving the accuracy and/or speed of clustering. The toolbox divides the cluster ensemble problem into four areas, providing functionality for each. These include, (1) synthetic data generation, (2) clustering to generate individual data partitions and similarity matrices, (3) consensus function generation and final clustering to generate ensemble data partitioning, and (4) implementation of accuracy metrics. Withmore » regard to data generation, Gaussian data of arbitrary dimension can be generated. The kcenters algorithm can then be used to generate individual data partitions by either, (a) subsampling the data and clustering each subsample, or by (b) randomly initializing the algorithm and generating a clustering for each initialization. In either case an overall similarity matrix can be computed using a consensus function operating on the individual similarity matrices. A final clustering can be performed and performance metrics are provided for evaluation purposes.« less

  13. α -cluster asymptotic normalization coefficients for nuclear...

    Office of Scientific and Technical Information (OSTI)

    -cluster asymptotic normalization coefficients for nuclear astrophysics Citation Details In-Document Search Title: -cluster asymptotic normalization coefficients for nuclear ...

  14. A discussion on the origin of quantum probabilities

    SciTech Connect (OSTI)

    Holik, Federico; Departamento de Matemtica - Ciclo Bsico Comn, Universidad de Buenos Aires - Pabelln III, Ciudad Universitaria, Buenos Aires ; Senz, Manuel; Plastino, Angel

    2014-01-15

    We study the origin of quantum probabilities as arising from non-Boolean propositional-operational structures. We apply the method developed by Cox to non distributive lattices and develop an alternative formulation of non-Kolmogorovian probability measures for quantum mechanics. By generalizing the method presented in previous works, we outline a general framework for the deduction of probabilities in general propositional structures represented by lattices (including the non-distributive case). -- Highlights: Several recent works use a derivation similar to that of R.T. Cox to obtain quantum probabilities. We apply Coxs method to the lattice of subspaces of the Hilbert space. We obtain a derivation of quantum probabilities which includes mixed states. The method presented in this work is susceptible to generalization. It includes quantum mechanics and classical mechanics as particular cases.

  15. Attempt to extract the preformation probability of. cap alpha...

    Office of Scientific and Technical Information (OSTI)

    Using the improved method we have fitted the experimental double differential energy spectrum of the sup 8Be cluster coming from the reaction sup 208Pb(sup 12C, sup 8Be) ...

  16. Ultraviolet and infrared laser-induced fragmentation of free (CF{sub 3}I){sub n} clusters in a molecular beam and (CF{sub 3}I){sub n} clusters inside or on the surface of large (Xe){sub m} clusters

    SciTech Connect (OSTI)

    Apatin, V. M.; Lokhman, V. N.; Makarov, G. N. Ogurok, N.-D. D.; Petin, A. N.; Ryabov, E. A.

    2015-02-15

    The fragmentation of free homogeneous (CF{sub 3}I){sub n} clusters in a molecular beam (n ≤ 45 is the average number of molecules in the cluster) and (CF{sub 3}I){sub n} clusters inside or on the surface of large (Xe){sub m} clusters (m ≥ 100 is the average number of atoms in the cluster) by ultraviolet and infrared laser radiations has been studied. These three types of (CF{sub 3}I){sub n} clusters are shown to have different stabilities with respect to fragmentation by both ultraviolet and infrared radiations and completely different dependences of the fragmentation probability on the energy of ultraviolet and infrared radiations. When exposed to ultraviolet radiation, the free (CF{sub 3}I){sub n} clusters fragment at comparatively low fluences (Φ{sub UV} ≤ 0.15 J cm{sup −2}) and the weakest energy dependence of the fragmentation probability is observed for them. A stronger energy dependence of the fragmentation probability is observed for the (CF{sub 3}I){sub n} clusters localized inside (Xe){sub m} clusters, and the strongest dependence is observed for the (CF{sub 3}I){sub n} clusters located on the surface of (Xe){sub m} clusters. When the clusters are exposed to infrared radiation, the homogeneous (CF{sub 3}I){sub n} clusters efficiently fragment at low fluences (Φ{sub IR} ≤ 25 mJ cm{sup −2}), higher fluences (Φ{sub IR} ≈ 75 mJ cm{sup −2}) are needed for the fragmentation of the (CF{sub 3}I){sub n} localized inside (Xe){sub m} clusters, and even higher fluences (Φ{sub IR} ≈ 150 mJ cm{sup −2}) are needed for the fragmentation of the (CF{sub 3}I){sub n} clusters located on the surface of (Xe){sub m} clusters. It has been established that small (CF{sub 3}I){sub n} clusters located on the surface of (Xe){sub m} clusters do not fragment up to fluences Φ{sub IR} ≈ 250 mJ cm{sup −2}. The fragmentation efficiency of (CF{sub 3}I){sub n} clusters is shown to be the same (at the same fluence) when they are excited by both pulsed (τ{sub p}

  17. Research Areas

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

    in diverse research areas such as cell biology, lithography, infrared microscopy, radiology, and x-ray tomography. Time-Resolved These techniques exploit the pulsed nature of...

  18. Bay Area

    National Nuclear Security Administration (NNSA)

    8%2A en NNSA to Conduct Aerial Radiological Surveys Over San Francisco, Pacifica, Berkeley, And Oakland, CA Areas http:nnsa.energy.govmediaroompressreleasesamsca

  19. Review of Literature for Model Assisted Probability of Detection

    SciTech Connect (OSTI)

    Meyer, Ryan M.; Crawford, Susan L.; Lareau, John P.; Anderson, Michael T.

    2014-09-30

    This is a draft technical letter report for NRC client documenting a literature review of model assisted probability of detection (MAPOD) for potential application to nuclear power plant components for improvement of field NDE performance estimations.

  20. Quantification of the effects of dependence on human error probabiliti...

    Office of Scientific and Technical Information (OSTI)

    In estimating the probabilities of human error in the performance of a series of tasks in a nuclear power plant, the situation-specific characteristics of the series must be ...

  1. Analysis of Cluster Management Tools

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

    Analysis of Configuration Management Tools Computer System, Cluster, and Networking Summer Institute Team: Evan Leeseberg, James Kang, Katherine Nystrom Mentors: Kevin Tegtmeier,...

  2. Parkes H I observations of southern globular clusters - Implications for stellar mass loss

    SciTech Connect (OSTI)

    Smith, G.H.; Wood, P.R.; Faulkner, D.J.; Wright, A.E. CSIRO, Australia Telescope National Facility, Parkes )

    1990-04-01

    A search for neutral hydrogen 21 cm emission has been made in the direction of the globular clusters 47 Tuc, NGC 1851, Omega Cen, and NGC 6388. Emission from NGC 6388 and 47 Tuc is observed close to the systemic velocity of the clusters, making it difficult to identify any weak features which might be associated with the clusters. A significant 21 cm emission profile is observed in the direction of Omega Cen, blueshifted by about 40 km/s with respect to the cluster. The emission probably arises from a high-velocity cloud with hydrogen column density of about 3 x 10 to the 18th atoms/sq cm. No emission is observed at the radial velocity of NGC 1851, and an upper limit of about nine solar masses can be placed on the amount of neutral hydrogen within this cluster. 61 refs.

  3. Aerosol cluster impact and break-up : II. Atomic and Cluster Scale Models.

    SciTech Connect (OSTI)

    Lechman, Jeremy B.; Takato, Yoichi

    2010-09-01

    Understanding the interaction of aerosol particle clusters/flocs with surfaces is an area of interest for a number of processes in chemical, pharmaceutical, and powder manufacturing as well as in steam-tube rupture in nuclear power plants. Developing predictive capabilities for these applications involves coupled phenomena on multiple length and timescales from the process macroscopic scale ({approx}1m) to the multi-cluster interaction scale (1mm-0.1m) to the single cluster scale ({approx}1000 - 10000 particles) to the particle scale (10nm-10{micro}m) interactions, and on down to the sub-particle, atomic scale interactions. The focus of this report is on the single cluster scale; although work directed toward developing better models of particle-particle interactions by considering sub-particle scale interactions and phenomena is also described. In particular, results of mesoscale (i.e., particle to single cluster scale) discrete element method (DEM) simulations for aerosol cluster impact with rigid walls are presented. The particle-particle interaction model is based on JKR adhesion theory and is implemented as an enhancement to the granular package in the LAMMPS code. The theory behind the model is outlined and preliminary results are shown. Additionally, as mentioned, results from atomistic classical molecular dynamics simulations are also described as a means of developing higher fidelity models of particle-particle interactions. Ultimately, the results from these and other studies at various scales must be collated to provide systems level models with accurate 'sub-grid' information for design, analysis and control of the underlying systems processes.

  4. Performance of the Rayleigh task based on the posterior probability of tomographic reconstructions

    SciTech Connect (OSTI)

    Hanson, K.M.

    1991-01-01

    We seek the best possible performance of the Rayleigh task in which one must decide whether a perceived object is a pair of Gaussian-blurred points or a blurred line. Two Bayesian reconstruction algorithms are used, the first based on a Gaussian prior-probability distribution with a nonnegativity constraint and the second based on an entropic prior. In both cases, the reconstructions are found that maximize the posterior probability. We compare the performance of the Rayleigh task obtained with two decision variables, the logarithm of the posterior probability ratio and the change in the mean-squared deviation from the reconstruction. The method of evaluation is based on the results of a numerical testing procedure in which the stated discrimination task is carried out on reconstructions of a randomly generated sequence of images. The ability to perform the Rayleigh task is summarized in terms of a discrimination index that is derived from the area under the receiver-operating characteristic (ROC) curve. We find that the use of the posterior probability does not result in better performance of the Rayleigh task than the mean-squared deviation from the reconstruction. 10 refs., 6 figs.

  5. Antibody-gold cluster conjugates

    DOE Patents [OSTI]

    Hainfeld, J.F.

    1988-06-28

    Antibody- or antibody fragment-gold cluster conjugates are shown wherein the conjugate size can be about 5.0 nm. Methods and reagents are disclosed in which antibodies or Fab' fragments thereof are covalently bound to a stable cluster of gold atoms. 2 figs.

  6. Single System Image Cluster Management

    Energy Science and Technology Software Center (OSTI)

    2004-02-13

    Cluster computing has quickly proven itself to be a capable workhorse for a wide variety of production computing tasks; however, setting up and maintaining a cluster still requires significantly more effort than administrating just a single machine. As computing hardware descreases in price and cluster sizes grow, it is becoming increasingly important to manage clusters cleverly so that a system administration effort can "scale" as well. To ease the task of mananging many machines, administratorsmore » often deploy an environment that is homogeneous across all nodes of a cluster, and maintain a snapshot of the filesystem as a 'master image'. However due to operational, behavioral, and physical constraints, many nodes often require numerous deviations from the master image in order to operate as desired.« less

  7. CAN COUPLED DARK ENERGY SPEED UP THE BULLET CLUSTER?

    SciTech Connect (OSTI)

    Lee, Jounghun; Baldi, Marco E-mail: marco.baldi@universe-cluster.de

    2012-03-01

    It has been recently shown that the observed morphological properties of the Bullet Cluster can be accurately reproduced in hydrodynamical simulations only when the infall pairwise velocity V{sub c} of the system exceeds 3000 km s{sup -1} (or at least possibly 2500 km s{sup -1}) at the pair separation of 2R{sub vir}, where R{sub vir} is the virial radius of the main cluster, and that the probability of finding such a bullet-like system is extremely low in the standard {Lambda} cold dark matter ({Lambda}CDM) cosmology. We suggest here the fifth force mediated by coupled dark energy (cDE) as a possible velocity-enhancing mechanism and investigate its effect on the infall velocities of bullet-like systems from the Coupled Dark Energy Cosmological Simulations public database. Five different cDE models are considered: three with constant coupling and exponential potential, one with exponential coupling and exponential potential, and one with constant coupling and supergravity potential. For each model, after identifying the bullet-like systems, we determine the probability density distribution of their infall velocities at pair separations of (2-3)R{sub vir}. Approximating each probability density distribution as a Gaussian, we calculate the cumulative probability of finding a bullet-like system with V{sub c} {>=} 3000 km s{sup -1} or V{sub c} {>=} 2500 km s{sup -1}. Our results show that in all of the five cDE models the cumulative probabilities increase compared to the {Lambda}CDM case and that in the model with exponential coupling P(V{sub c} {>=} 2500 km s{sup -1}) exceeds 10{sup -4}. The physical interpretations and cosmological implications of our results are provided.

  8. Probability, consequences, and mitigation for lightning strikes to Hanford site high-level waste tanks

    SciTech Connect (OSTI)

    Zach, J.J.

    1996-08-01

    The purpose of this report is to summarize selected lightning issues concerning the Hanford Waste Tanks. These issues include the probability of lightning discharge striking the area immediately adjacent to a tank including a riser, the consequences of significant energy deposition from a lightning strike in a tank, and mitigating actions that have been or are being taken. The major conclusion of this report is that the probability of a lightning strike depositing sufficient energy in a tank to cause an effect on employees or the public is unlikely;but there are insufficient, quantitative data on the tanks and waste to prove that. Protection, such as grounding of risers and air terminals on existing light poles, is recommended.

  9. Probability, consequences, and mitigation for lightning strikes of Hanford high level waste tanks

    SciTech Connect (OSTI)

    Zach, J.J.

    1996-06-05

    The purpose of this report is to summarize selected lightning issues concerning the Hanford Waste Tanks. These issues include the probability of a lightning discharge striking the area immediately adjacent to a tank including a riser, the consequences of significant energy deposition from a lightning strike in a tank, and mitigating actions that have been or are being taken. The major conclusion of this report is that the probability of a lightning strike deposition sufficient energy in a tank to cause an effect on employees or the public is unlikely;but there are insufficient, quantitative data on the tanks and waste to prove that. Protection, such as grounding of risers and air terminals on existing light poles, is recommended.

  10. Bayesian Estimator of Protein-Protein Association Probabilities

    Energy Science and Technology Software Center (OSTI)

    2008-05-28

    The Bayesian Estimator of Protein-Protein Association Probabilities (BEPro3) is a software tool for estimating probabilities of protein-protein association between bait and prey protein pairs using data from multiple-bait, multiple-replicate, protein LC-MS/MS affinity isolation experiments. BEPro3 is public domain software, has been tested on Windows XP and version 10.4 or newer of the Mac OS 10.4, and is freely available. A user guide, example dataset with analysis and additional documentation are included with the BEPro3 download.

  11. Dust cluster explosion

    SciTech Connect (OSTI)

    Saxena, Vikrant [School of Mathematics and Physics, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Institute for Plasma Research, Bhat, Gandhinagar (India); Avinash, K. [Department of Physics and Astrophysics, University of Delhi, New Delhi (India); Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar (India)

    2012-09-15

    A model for the dust cluster explosion where micron/sub-micron sized particles are accelerated at the expense of plasma thermal energy, in the afterglow phase of a complex plasma discharge is proposed. The model is tested by molecular dynamics simulations of dust particles in a confining potential. The nature of the explosion (caused by switching off the discharge) and the concomitant dust acceleration is found to depend critically on the pressure of the background neutral gas. At low gas pressure, the explosion is due to unshielded Coulomb repulsion between dust particles and yields maximum acceleration, while in the high pressure regime it is due to shielded Yukawa repulsion and yields much feebler acceleration. These results are in agreement with experimental findings. Our simulations also confirm a recently proposed electrostatic (ES) isothermal scaling relation, P{sub E}{proportional_to}V{sub d}{sup -2} (where P{sub E} is the ES pressure of the dust particles and V{sub d} is the confining volume).

  12. Advanced Health Monitoring of Computer Cluster

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

    Sherry Salas Mentors: Susan Coulter, Andree Jacobson, Kevin Tegtmeier LANL ISTIIAS ClusterNetwork Management Summer Institute August 2, 2007 Problem As a cluster grows in...

  13. Calculating the probability of injected carbon dioxide plumes encountering faults

    SciTech Connect (OSTI)

    Jordan, P.D.

    2011-04-01

    One of the main concerns of storage in saline aquifers is leakage via faults. In the early stages of site selection, site-specific fault coverages are often not available for these aquifers. This necessitates a method using available fault data to estimate the probability of injected carbon dioxide encountering and migrating up a fault. The probability of encounter can be calculated from areal fault density statistics from available data, and carbon dioxide plume dimensions from numerical simulation. Given a number of assumptions, the dimension of the plume perpendicular to a fault times the areal density of faults with offsets greater than some threshold of interest provides probability of the plume encountering such a fault. Application of this result to a previously planned large-scale pilot injection in the southern portion of the San Joaquin Basin yielded a 3% and 7% chance of the plume encountering a fully and half seal offsetting fault, respectively. Subsequently available data indicated a half seal-offsetting fault at a distance from the injection well that implied a 20% probability of encounter for a plume sufficiently large to reach it.

  14. Modeling highway travel time distribution with conditional probability models

    SciTech Connect (OSTI)

    Oliveira Neto, Francisco Moraes; Chin, Shih-Miao; Hwang, Ho-Ling; Han, Lee

    2014-01-01

    ABSTRACT Under the sponsorship of the Federal Highway Administration's Office of Freight Management and Operations, the American Transportation Research Institute (ATRI) has developed performance measures through the Freight Performance Measures (FPM) initiative. Under this program, travel speed information is derived from data collected using wireless based global positioning systems. These telemetric data systems are subscribed and used by trucking industry as an operations management tool. More than one telemetric operator submits their data dumps to ATRI on a regular basis. Each data transmission contains truck location, its travel time, and a clock time/date stamp. Data from the FPM program provides a unique opportunity for studying the upstream-downstream speed distributions at different locations, as well as different time of the day and day of the week. This research is focused on the stochastic nature of successive link travel speed data on the continental United States Interstates network. Specifically, a method to estimate route probability distributions of travel time is proposed. This method uses the concepts of convolution of probability distributions and bivariate, link-to-link, conditional probability to estimate the expected distributions for the route travel time. Major contribution of this study is the consideration of speed correlation between upstream and downstream contiguous Interstate segments through conditional probability. The established conditional probability distributions, between successive segments, can be used to provide travel time reliability measures. This study also suggests an adaptive method for calculating and updating route travel time distribution as new data or information is added. This methodology can be useful to estimate performance measures as required by the recent Moving Ahead for Progress in the 21st Century Act (MAP 21).

  15. A Clustering Graph Generator

    SciTech Connect (OSTI)

    Winlaw, Manda; De Sterck, Hans; Sanders, Geoffrey

    2015-10-26

    In very simple terms a network can be de ned as a collection of points joined together by lines. Thus, networks can be used to represent connections between entities in a wide variety of elds including engi- neering, science, medicine, and sociology. Many large real-world networks share a surprising number of properties, leading to a strong interest in model development research and techniques for building synthetic networks have been developed, that capture these similarities and replicate real-world graphs. Modeling these real-world networks serves two purposes. First, building models that mimic the patterns and prop- erties of real networks helps to understand the implications of these patterns and helps determine which patterns are important. If we develop a generative process to synthesize real networks we can also examine which growth processes are plausible and which are not. Secondly, high-quality, large-scale network data is often not available, because of economic, legal, technological, or other obstacles [7]. Thus, there are many instances where the systems of interest cannot be represented by a single exemplar network. As one example, consider the eld of cybersecurity, where systems require testing across diverse threat scenarios and validation across diverse network structures. In these cases, where there is no single exemplar network, the systems must instead be modeled as a collection of networks in which the variation among them may be just as important as their common features. By developing processes to build synthetic models, so-called graph generators, we can build synthetic networks that capture both the essential features of a system and realistic variability. Then we can use such synthetic graphs to perform tasks such as simulations, analysis, and decision making. We can also use synthetic graphs to performance test graph analysis algorithms, including clustering algorithms and anomaly detection algorithms.

  16. Industry Cluster Development Grant winners

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

    Industry Cluster Development Grant winners Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Industry Cluster Development Grant winners Recipients include Picuris Pueblo and Rio Arriba County February 1, 2015 A new community mural on the Hunter Ford facility in Española celebrates the building's planned revitalization and the future location of the Northern New Mexico Food Hub. A new

  17. Simple and compact expressions for neutrino oscillation probabilities in matter

    SciTech Connect (OSTI)

    Minakata, Hisakazu; Parke, Stephen J.

    2015-05-07

    We reformulate perturbation theory for neutrino oscillations in matter with an expansion parameter related to the ratio of the solar to the atmospheric ?m2 scales. Unlike previous works, use a renormalized basis in which certain first-order effects are taken into account in the zeroth-order Hamiltonian. Using this perturbation theory we derive extremely compact expressions for the neutrino oscillations probabilities in matter. We find, for example, that the ?e disappearance probability at this order is of a simple two flavor form with an appropriately identified mixing angle and ?m2. Furthermore, despite exceptional simplicity in their forms they accommodate all order effects ?13 and the matter potential.

  18. Improvements in release probability by using an overpack. [Obsolete munitions

    SciTech Connect (OSTI)

    Rhyne, W.R.; Ashwood, T.L.; Shappert, L.B.

    1986-01-01

    An analysis was performed to determine the probability of an unconfined release of hazardous material as a consequence of being involved in a severe transportation accident. Two packaging scenarios were considered: (1) material was palletized and placed in a standard aluminum sided trailer, and (2) the same material was placed in an overpackage. In addition to truck, both rail and air transport were also considered. Several release categories were defined ranging from minor to very large, and the effectiveness of the overpackage to reduce the probability of unconfined release was evaluated for each type of release category. The results are applicable to the transport of radioactive materials in similar overpackages. The potential accident scenarios for a pallet of obsolete munitions were identified using a fault-free methodology.

  19. Optimized Algorithm for Collision Probability Calculations in Cubic Geometry

    SciTech Connect (OSTI)

    Garcia, R.D.M.

    2004-06-15

    An optimized algorithm for implementing a recently developed method of computing collision probabilities (CPs) in three dimensions is reported in this work for the case of a homogeneous cube. Use is made of the geometrical regularity of the domain to rewrite, in a very compact way, the approximate formulas for calculating CPs in general three-dimensional geometry that were derived in a previous work by the author. The ensuing gain in computation time is found to be substantial: While the computation time associated with the general formulas increases as K{sup 2}, where K is the number of elements used in the calculation, that of the specific formulas increases only linearly with K. Accurate numerical results are given for several test cases, and an extension of the algorithm for computing the self-collision probability for a hexahedron is reported at the end of the work.

  20. Evaluations of Structural Failure Probabilities and Candidate Inservice Inspection Programs

    SciTech Connect (OSTI)

    Khaleel, Mohammad A.; Simonen, Fredric A.

    2009-05-01

    The work described in this report applies probabilistic structural mechanics models to predict the reliability of nuclear pressure boundary components. These same models are then applied to evaluate the effectiveness of alternative programs for inservice inspection to reduce these failure probabilities. Results of the calculations support the development and implementation of risk-informed inservice inspection of piping and vessels. Studies have specifically addressed the potential benefits of ultrasonic inspections to reduce failure probabilities associated with fatigue crack growth and stress-corrosion cracking. Parametric calculations were performed with the computer code pc-PRAISE to generate an extensive set of plots to cover a wide range of pipe wall thicknesses, cyclic operating stresses, and inspection strategies. The studies have also addressed critical inputs to fracture mechanics calculations such as the parameters that characterize the number and sizes of fabrication flaws in piping welds. Other calculations quantify uncertainties associated with the inputs calculations, the uncertainties in the fracture mechanics models, and the uncertainties in the resulting calculated failure probabilities. A final set of calculations address the effects of flaw sizing errors on the effectiveness of inservice inspection programs.

  1. Internal gettering by metal alloy clusters

    DOE Patents [OSTI]

    Buonassisi, Anthony; Heuer, Matthias; Istratov, Andrei A.; Pickett, Matthew D.; Marcus, Mathew A.; Weber, Eicke R.

    2010-07-27

    The present invention relates to the internal gettering of impurities in semiconductors by metal alloy clusters. In particular, intermetallic clusters are formed within silicon, such clusters containing two or more transition metal species. Such clusters have melting temperatures below that of the host material and are shown to be particularly effective in gettering impurities within the silicon and collecting them into isolated, less harmful locations. Novel compositions for some of the metal alloy clusters are also described.

  2. Course Clusters | Photosynthetic Antenna Research Center

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

    Course Clusters Course Clusters Courses are organized into three discipline clusters: (1) Social Sciences & Humanities; (2) Architecture; and, (3) Natural Sciences & Engineering. According to the certificate's requirements, students must select curriculum options from at least two of the three clusters. Course information and/or descriptions that appear below were obtained from courses.wustl.edu. Please also see our printable course listing. Register for courses on WebSTAC. Cluster #1:

  3. Quantum Monte Carlo methods and lithium cluster properties. [Atomic clusters

    SciTech Connect (OSTI)

    Owen, R.K.

    1990-12-01

    Properties of small lithium clusters with sizes ranging from n = 1 to 5 atoms were investigated using quantum Monte Carlo (QMC) methods. Cluster geometries were found from complete active space self consistent field (CASSCF) calculations. A detailed development of the QMC method leading to the variational QMC (V-QMC) and diffusion QMC (D-QMC) methods is shown. The many-body aspect of electron correlation is introduced into the QMC importance sampling electron-electron correlation functions by using density dependent parameters, and are shown to increase the amount of correlation energy obtained in V-QMC calculations. A detailed analysis of D-QMC time-step bias is made and is found to be at least linear with respect to the time-step. The D-QMC calculations determined the lithium cluster ionization potentials to be 0.1982(14) (0.1981), 0.1895(9) (0.1874(4)), 0.1530(34) (0.1599(73)), 0.1664(37) (0.1724(110)), 0.1613(43) (0.1675(110)) Hartrees for lithium clusters n = 1 through 5, respectively; in good agreement with experimental results shown in the brackets. Also, the binding energies per atom was computed to be 0.0177(8) (0.0203(12)), 0.0188(10) (0.0220(21)), 0.0247(8) (0.0310(12)), 0.0253(8) (0.0351(8)) Hartrees for lithium clusters n = 2 through 5, respectively. The lithium cluster one-electron density is shown to have charge concentrations corresponding to nonnuclear attractors. The overall shape of the electronic charge density also bears a remarkable similarity with the anisotropic harmonic oscillator model shape for the given number of valence electrons.

  4. GAMMA RAYS FROM STAR FORMATION IN CLUSTERS OF GALAXIES

    SciTech Connect (OSTI)

    Storm, Emma M.; Jeltema, Tesla E.; Profumo, Stefano

    2012-08-20

    Star formation in galaxies is observed to be associated with gamma-ray emission, presumably from non-thermal processes connected to the acceleration of cosmic-ray nuclei and electrons. The detection of gamma rays from starburst galaxies by the Fermi Large Area Telescope (LAT) has allowed the determination of a functional relationship between star formation rate and gamma-ray luminosity. Since star formation is known to scale with total infrared (8-1000 {mu}m) and radio (1.4 GHz) luminosity, the observed infrared and radio emission from a star-forming galaxy can be used to quantitatively infer the galaxy's gamma-ray luminosity. Similarly, star-forming galaxies within galaxy clusters allow us to derive lower limits on the gamma-ray emission from clusters, which have not yet been conclusively detected in gamma rays. In this study, we apply the functional relationships between gamma-ray luminosity and radio and IR luminosities of galaxies derived by the Fermi Collaboration to a sample of the best candidate galaxy clusters for detection in gamma rays in order to place lower limits on the gamma-ray emission associated with star formation in galaxy clusters. We find that several clusters have predicted gamma-ray emission from star formation that are within an order of magnitude of the upper limits derived in Ackermann et al. based on non-detection by Fermi-LAT. Given the current gamma-ray limits, star formation likely plays a significant role in the gamma-ray emission in some clusters, especially those with cool cores. We predict that both Fermi-LAT over the course of its lifetime and the future Cerenkov Telescope Array will be able to detect gamma-ray emission from star-forming galaxies in clusters.

  5. NEW LIMITS ON GAMMA-RAY EMISSION FROM GALAXY CLUSTERS

    SciTech Connect (OSTI)

    Griffin, Rhiannon D.; Dai, Xinyu; Kochanek, Christopher S. E-mail: xdai@ou.edu

    2014-11-01

    Galaxy clusters are predicted to produce γ-rays through cosmic ray interactions and/or dark matter annihilation, potentially detectable by the Fermi Large Area Telescope (Fermi-LAT). We present a new, independent stacking analysis of Fermi-LAT photon count maps using the 78 richest nearby clusters (z < 0.12) from the Two Micron All Sky Survey cluster catalog. We obtain the lowest limit on the photon flux to date, 2.3 × 10{sup –11} photons cm{sup –2} s{sup –1} (95% confidence) per cluster in the 0.8-100 GeV band, which corresponds to a luminosity limit of 3.5 × 10{sup 44} photons s{sup –1}. We also constrain the emission limits in a range of narrower energy bands. Scaling to recent cosmic ray acceleration and γ-ray emission models, we find that cosmic rays represent a negligible contribution to the intra-cluster energy density and gas pressure.

  6. Simplifying Probability Elicitation and Uncertainty Modeling in Bayesian Networks

    SciTech Connect (OSTI)

    Paulson, Patrick R; Carroll, Thomas E; Sivaraman, Chitra; Neorr, Peter A; Unwin, Stephen D; Hossain, Shamina S

    2011-04-16

    In this paper we contribute two methods that simplify the demands of knowledge elicitation for particular types of Bayesian networks. The first method simplify the task of providing probabilities when the states that a random variable takes can be described by a new, fully ordered state set in which a state implies all the preceding states. The second method leverages Dempster-Shafer theory of evidence to provide a way for the expert to express the degree of ignorance that they feel about the estimates being provided.

  7. Detection probabilities for random inspection in variable flow situations

    SciTech Connect (OSTI)

    Lu, Ming-Shih

    1994-03-01

    Improvements in the efficiency and effectiveness of inventory-change verification are necessary at certain nuclear facilities, of which one example is low-enriched uranium fuel fabrication facilities. The Safeguards Criteria suggested carrying out interim inventory-change verifications with randomized inspections. This paper describes randomized inspection schemes for inventory change verifications and evaluates the achievable detection probabilities for realistic plant receipt and shipment schedules and stratum residence times as a. function of the inspection frequency and effort and compares these with the existing inspection strategies.

  8. THE ACS FORNAX CLUSTER SURVEY. VI. THE NUCLEI OF EARLY-TYPE GALAXIES IN THE FORNAX CLUSTER

    SciTech Connect (OSTI)

    Turner, Monica L.; Cote, Patrick; Ferrarese, Laura; Blakeslee, John P.; Jordan, Andres; Mei, Simona; Peng, Eric W.; West, Michael J.

    2012-11-15

    The Advanced Camera for Surveys (ACS) Fornax Cluster Survey is a Hubble Space Telescope program to image 43 early-type galaxies in the Fornax cluster, using the F475W and F850LP bandpasses of the ACS. We employ both one-dimensional and two-dimensional techniques to characterize the properties of the stellar nuclei in these galaxies, defined as the central 'luminosity excesses', relative to a Sersic model fitted to the underlying host. We find 72% {+-} 13% of our sample (31 galaxies) to be nucleated, with only three of the nuclei offset by more than 0.''5 from their galaxy photocenter, and with the majority of nuclei having colors bluer than their hosts. The nuclei are observed to be larger, and brighter, than typical Fornax globular clusters and to follow different structural scaling relations. A comparison of our results to those from the ACS Virgo Cluster Survey reveals striking similarities in the properties of the nuclei belonging to these different environments. We briefly review a variety of proposed formation models and conclude that, for the low-mass galaxies in our sample, the most important mechanism for nucleus growth is probably infall of star clusters through dynamical friction, while for higher mass galaxies, gas accretion triggered by mergers, accretions, and tidal torques is likely to dominate, with the relative importance of these two processes varying smoothly as a function of galaxy mass. Some intermediate-mass galaxies in our sample show a complexity in their inner structure that may be the signature of the 'hybrid nuclei' that arose through parallel formation channels.

  9. Star formation and substructure in galaxy clusters

    SciTech Connect (OSTI)

    Cohen, Seth A.; Hickox, Ryan C.; Wegner, Gary A.; Einasto, Maret; Vennik, Jaan

    2014-03-10

    We investigate the relationship between star formation (SF) and substructure in a sample of 107 nearby galaxy clusters using data from the Sloan Digital Sky Survey. Several past studies of individual galaxy clusters have suggested that cluster mergers enhance cluster SF, while others find no such relationship. The SF fraction in multi-component clusters (0.228 0.007) is higher than that in single-component clusters (0.175 0.016) for galaxies with M{sub r}{sup 0.1}clusters, the fraction of star-forming galaxies increases with clustercentric distance and decreases with local galaxy number density, and multi-component clusters show a higher SF fraction than single-component clusters at almost all clustercentric distances and local densities. Comparing the SF fraction in individual clusters to several statistical measures of substructure, we find weak, but in most cases significant at greater than 2?, correlations between substructure and SF fraction. These results could indicate that cluster mergers may cause weak but significant SF enhancement in clusters, or unrelaxed clusters exhibit slightly stronger SF due to their less evolved states relative to relaxed clusters.

  10. Evidence for particle re-acceleration in the radio relic in the galaxy cluster PLCKG287.0+32.9

    SciTech Connect (OSTI)

    Bonafede, A.; Brggen, M.; Intema, H. T.; Girardi, M.; Nonino, M.; Kantharia, N.; Van Weeren, R. J.; Rttgering, H. J. A.

    2014-04-10

    Radio relics are diffuse radio sources observed in galaxy clusters, probably produced by shock acceleration during cluster-cluster mergers. Their large size, of the order of 1 Mpc, indicates that the emitting electrons need to be (re)accelerated locally. The usually invoked diffusive shock acceleration models have been challenged by recent observations and theory. We report the discovery of complex radio emission in the Galaxy cluster PLCKG287.0+32.9, which hosts two relics, a radio halo, and several radio filamentary emission. Optical observations suggest that the cluster is elongated, likely along an intergalactic filament, and displays a significant amount of substructure. The peculiar features of this radio relic are that (1) it appears to be connected to the lobes of a radio galaxy and (2) the radio spectrum steepens on either side of the radio relic. We discuss the origins of these features in the context of particle re-acceleration.

  11. Quantum probabilities from quantum entanglement: experimentally unpacking the Born rule

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

    Harris, Jérémie; Bouchard, Frédéric; Santamato, Enrico; Zurek, Wojciech H.; Boyd, Robert W.; Karimi, Ebrahim

    2016-05-11

    The Born rule, a foundational axiom was used to deduce probabilities of events from wavefunctions, is indispensable in the everyday practice of quantum physics. It is also key in the quest to reconcile the ostensibly inconsistent laws of the quantum and classical realms, as it confers physical significance to reduced density matrices, the essential tools of decoherence theory. Following Bohr's Copenhagen interpretation, textbooks postulate the Born rule outright. But, recent attempts to derive it from other quantum principles have been successful, holding promise for simplifying and clarifying the quantum foundational bedrock. Moreover, a major family of derivations is based onmore » envariance, a recently discovered symmetry of entangled quantum states. Here, we identify and experimentally test three premises central to these envariance-based derivations, thus demonstrating, in the microworld, the symmetries from which the Born rule is derived. Furthermore, we demonstrate envariance in a purely local quantum system, showing its independence from relativistic causality.« less

  12. Matter-enhanced transition probabilities in quantum field theory

    SciTech Connect (OSTI)

    Ishikawa, Kenzo Tobita, Yutaka

    2014-05-15

    The relativistic quantum field theory is the unique theory that combines the relativity and quantum theory and is invariant under the Poincar transformation. The ground state, vacuum, is singlet and one particle states are transformed as elements of irreducible representation of the group. The covariant one particles are momentum eigenstates expressed by plane waves and extended in space. Although the S-matrix defined with initial and final states of these states hold the symmetries and are applied to isolated states, out-going states for the amplitude of the event that they are detected at a finite-time interval T in experiments are expressed by microscopic states that they interact with, and are surrounded by matters in detectors and are not plane waves. These matter-induced effects modify the probabilities observed in realistic situations. The transition amplitudes and probabilities of the events are studied with the S-matrix, S[T], that satisfies the boundary condition at T. Using S[T], the finite-size corrections of the form of 1/T are found. The corrections to Fermis golden rule become larger than the original values in some situations for light particles. They break Lorentz invariance even in high energy region of short de Broglie wave lengths. -- Highlights: S-matrix S[T] for the finite-time interval in relativistic field theory. S[T] satisfies the boundary condition and gives correction of 1/T . The large corrections for light particles breaks Lorentz invariance. The corrections have implications to neutrino experiments.

  13. THE BURST CLUSTER: DARK MATTER IN A CLUSTER MERGER ASSOCIATED WITH THE SHORT GAMMA-RAY BURST, GRB 050509B

    SciTech Connect (OSTI)

    Dahle, H.; Sarazin, C. L.; Lopez, L. A.; Kouveliotou, C.; Rol, E.; Van der Horst, A. J.; Wijers, R. A. M. J.; Fynbo, J.; Michalowski, M. J.; Burrows, D. N.; Grupe, D.; Gehrels, N.

    2013-07-20

    . We also present our results from a weak-lensing survey based on archival Very Large Telescope images in the areas of five other short GRBs, which do not provide any firm detections of mass concentrations representative of rich clusters.

  14. A LITHIUM-RICH RED GIANT BELOW THE CLUMP IN THE KEPLER CLUSTER, NGC 6819

    SciTech Connect (OSTI)

    Anthony-Twarog, Barbara J.; Rich, Evan; Twarog, Bruce A.; Deliyannis, Constantine P. E-mail: evan66210@gmail.com E-mail: con@astro.indiana.edu

    2013-04-10

    WIYN/HYDRA spectra in the Li 6708 A region have been obtained for 332 probable members of the old open cluster, NGC 6819. Preliminary analysis shows a pattern of Li depletion from the top of the turnoff to the base of the giant branch. Starting 1 mag below the level of the clump, all brighter giants have A(Li) below 1.0, with most having upper limits below 0.5. Star W007017, located below the first-ascent red giant bump is Li-rich with A(Li) = 2.3. As a highly probable single-star astrometric and radial-velocity cluster member, its discrepant asteroseismic membership could be a by-product of the processes that triggered Li enhancement. Its color-magnitude diagram location is consistent with only one proposed enhanced mixing process among first-ascent red giants.

  15. STAR-FORMING GALAXY EVOLUTION IN NEARBY RICH CLUSTERS

    SciTech Connect (OSTI)

    Tyler, K. D.; Rieke, G. H.; Bai, L.

    2013-08-20

    Dense environments are known to quench star formation in galaxies, but it is still unknown what mechanism(s) are directly responsible. In this paper, we study the star formation of galaxies in A2029 and compare it to that of Coma, combining indicators at 24 {mu}m, H{alpha}, and UV down to rates of 0.03 M{sub Sun} yr{sup -1}. We show that A2029's star-forming galaxies follow the same mass-SFR relation as the field. The Coma cluster, on the other hand, has a population of galaxies with star formation rates (SFRs) significantly lower than the field mass-SFR relation, indicative of galaxies in the process of being quenched. Over half of these galaxies also host active galactic nuclei. Ram-pressure stripping and starvation/strangulation are the most likely mechanisms for suppressing the star formation in these galaxies, but we are unable to disentangle which is dominating. The differences we see between the two clusters' populations of star-forming galaxies may be related to their accretion histories, with A2029 having accreted its star-forming galaxies more recently than Coma. Additionally, many early-type galaxies in A2029 are detected at 24 {mu}m and/or in the far-UV, but this emission is not directly related to star formation. Similar galaxies have probably been classified as star forming in previous studies of dense clusters, possibly obscuring some of the effects of the cluster environment on true star-forming galaxies.

  16. WIYN OPEN CLUSTER STUDY. LV. ASTROMETRY AND MEMBERSHIP IN NGC 6819

    SciTech Connect (OSTI)

    Platais, Imants; Gosnell, Natalie M.; Meibom, Soren; Kozhurina-Platais, Vera; Bellini, Andrea; Veillet, Christian; Burkhead, Martin S.

    2013-08-01

    We present proper motions and astrometric membership analysis for 15,750 stars around the intermediate-age open cluster NGC 6819. The accuracy of relative proper motions for well-measured stars ranges from {approx}0.2 mas yr{sup -1} within 10' of the cluster center to 1.1 mas yr{sup -1} outside this radius. In the proper motion vector-point diagram, the separation between the cluster members and field stars is convincing down to V {approx} 18 and within 10' from the cluster center. The formal sum of membership probabilities indicates a total of {approx}2500 cluster members down to V {approx} 22. We confirm the cluster membership of several variable stars, including some eclipsing binaries. The estimated absolute proper motion of NGC 6819 is {mu}{sub x}{sup abs}=-2.6{+-}0.5 and {mu}{sub y}{sup abs}=-4.2{+-}0.5 mas yr{sup -1}. A cross-identification between the proper motion catalog and a list of X-ray sources in the field of NGC 6819 resulted in a number of new likely optical counterparts, including a candidate CV. For the first time we show that there is significant differential reddening toward NGC 6819.

  17. Pair extended coupled cluster doubles

    SciTech Connect (OSTI)

    Henderson, Thomas M.; Scuseria, Gustavo E.; Bulik, Ireneusz W.

    2015-06-07

    The accurate and efficient description of strongly correlated systems remains an important challenge for computational methods. Doubly occupied configuration interaction (DOCI), in which all electrons are paired and no correlations which break these pairs are permitted, can in many cases provide an accurate account of strong correlations, albeit at combinatorial computational cost. Recently, there has been significant interest in a method we refer to as pair coupled cluster doubles (pCCD), a variant of coupled cluster doubles in which the electrons are paired. This is simply because pCCD provides energies nearly identical to those of DOCI, but at mean-field computational cost (disregarding the cost of the two-electron integral transformation). Here, we introduce the more complete pair extended coupled cluster doubles (pECCD) approach which, like pCCD, has mean-field cost and reproduces DOCI energetically. We show that unlike pCCD, pECCD also reproduces the DOCI wave function with high accuracy. Moreover, pECCD yields sensible albeit inexact results even for attractive interactions where pCCD breaks down.

  18. Financial derivative pricing under probability operator via Esscher transfomation

    SciTech Connect (OSTI)

    Achi, Godswill U.

    2014-10-24

    The problem of pricing contingent claims has been extensively studied for non-Gaussian models, and in particular, Black- Scholes formula has been derived for the NIG asset pricing model. This approach was first developed in insurance pricing{sup 9} where the original distortion function was defined in terms of the normal distribution. This approach was later studied6 where they compared the standard Black-Scholes contingent pricing and distortion based contingent pricing. So, in this paper, we aim at using distortion operators by Cauchy distribution under a simple transformation to price contingent claim. We also show that we can recuperate the Black-Sholes formula using the distribution. Similarly, in a financial market in which the asset price represented by a stochastic differential equation with respect to Brownian Motion, the price mechanism based on characteristic Esscher measure can generate approximate arbitrage free financial derivative prices. The price representation derived involves probability Esscher measure and Esscher Martingale measure and under a new complex valued measure φ (u) evaluated at the characteristic exponents φ{sub x}(u) of X{sub t} we recuperate the Black-Scholes formula for financial derivative prices.

  19. Parameterizing deep convection using the assumed probability density function method

    SciTech Connect (OSTI)

    Storer, R. L.; Griffin, B. M.; Hoft, Jan; Weber, J. K.; Raut, E.; Larson, Vincent E.; Wang, Minghuai; Rasch, Philip J.

    2015-01-06

    Due to their coarse horizontal resolution, present-day climate models must parameterize deep convection. This paper presents single-column simulations of deep convection using a probability density function (PDF) parameterization. The PDF parameterization predicts the PDF of subgrid variability of turbulence, clouds, and hydrometeors. That variability is interfaced to a prognostic microphysics scheme using a Monte Carlo sampling method.The PDF parameterization is used to simulate tropical deep convection, the transition from shallow to deep convection over land, and mid-latitude deep convection.These parameterized single-column simulations are compared with 3-D reference simulations. The agreement is satisfactory except when the convective forcing is weak. The same PDF parameterization is also used to simulate shallow cumulus and stratocumulus layers. The PDF method is sufficiently general to adequately simulate these five deep, shallow, and stratiform cloud cases with a single equation set. This raises hopes that it may be possible in the future, with further refinements at coarse time step and grid spacing, to parameterize all cloud types in a large-scale model in a unified way.

  20. Probability of detection models for eddy current NDE methods

    SciTech Connect (OSTI)

    Rajesh, S.N.

    1993-04-30

    The development of probability of detection (POD) models for a variety of nondestructive evaluation (NDE) methods is motivated by a desire to quantify the variability introduced during the process of testing. Sources of variability involved in eddy current methods of NDE include those caused by variations in liftoff, material properties, probe canting angle, scan format, surface roughness and measurement noise. This thesis presents a comprehensive POD model for eddy current NDE. Eddy current methods of nondestructive testing are used widely in industry to inspect a variety of nonferromagnetic and ferromagnetic materials. The development of a comprehensive POD model is therefore of significant importance. The model incorporates several sources of variability characterized by a multivariate Gaussian distribution and employs finite element analysis to predict the signal distribution. The method of mixtures is then used for estimating optimal threshold values. The research demonstrates the use of a finite element model within a probabilistic framework to the spread in the measured signal for eddy current nondestructive methods. Using the signal distributions for various flaw sizes the POD curves for varying defect parameters have been computed. In contrast to experimental POD models, the cost of generating such curves is very low and complex defect shapes can be handled very easily. The results are also operator independent.

  1. Utilizing the sequential probability ratio test for building joint monitoring

    SciTech Connect (OSTI)

    Allen, D. W.; Sohn, H.; Worden, K.; Farrar, C. R.

    2002-01-01

    In this application of the statistical pattern recognition paradigm, a prediction model of a chosen feature is developed from the time domain response of a baseline structure. After the model is developed, subsequent feature sets are tested against the model to determine if a change in the feature has occurred. In the proposed statistical inference for damage identification there are two basic hypotheses; (1) the model can predict the feature, in which case the structure is undamaged or (2) the model can not accurately predict the feature, suggesting that the structure is damaged. The Sequential Probability Ratio Test (SPRT) develops a statistical method that quickly arrives at a decision between these two hypotheses and is applicable to continuous monitoring. In the original formulation of the SPRT algorithm, the feature is assumed to be Gaussian and thresholds are set accordingly. It is likely, however, that the feature used for damage identification is sensitive to the tails of the distribution and that the tails may not necessarily be governed by Gaussian characteristics. By modeling the tails using the technique of Extreme Value Statistics, the hypothesis decision thresholds for the SPRT algorithm may be set avoiding the normality assumption. The SPRT algorithm is utilized to decide if the test structure is undamaged or damaged and which joint is exhibiting the change.

  2. Parameterizing deep convection using the assumed probability density function method

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

    Storer, R. L.; Griffin, B. M.; Höft, J.; Weber, J. K.; Raut, E.; Larson, V. E.; Wang, M.; Rasch, P. J.

    2015-01-06

    Due to their coarse horizontal resolution, present-day climate models must parameterize deep convection. This paper presents single-column simulations of deep convection using a probability density function (PDF) parameterization. The PDF parameterization predicts the PDF of subgrid variability of turbulence, clouds, and hydrometeors. That variability is interfaced to a prognostic microphysics scheme using a Monte Carlo sampling method. The PDF parameterization is used to simulate tropical deep convection, the transition from shallow to deep convection over land, and midlatitude deep convection. These parameterized single-column simulations are compared with 3-D reference simulations. The agreement is satisfactory except when the convective forcing ismore » weak. The same PDF parameterization is also used to simulate shallow cumulus and stratocumulus layers. The PDF method is sufficiently general to adequately simulate these five deep, shallow, and stratiform cloud cases with a single equation set. This raises hopes that it may be possible in the future, with further refinements at coarse time step and grid spacing, to parameterize all cloud types in a large-scale model in a unified way.« less

  3. Parameterizing deep convection using the assumed probability density function method

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

    Storer, R. L.; Griffin, B. M.; Höft, J.; Weber, J. K.; Raut, E.; Larson, V. E.; Wang, M.; Rasch, P. J.

    2014-06-11

    Due to their coarse horizontal resolution, present-day climate models must parameterize deep convection. This paper presents single-column simulations of deep convection using a probability density function (PDF) parameterization. The PDF parameterization predicts the PDF of subgrid variability of turbulence, clouds, and hydrometeors. That variability is interfaced to a prognostic microphysics scheme using a Monte Carlo sampling method. The PDF parameterization is used to simulate tropical deep convection, the transition from shallow to deep convection over land, and mid-latitude deep convection. These parameterized single-column simulations are compared with 3-D reference simulations. The agreement is satisfactory except when the convective forcing ismore » weak. The same PDF parameterization is also used to simulate shallow cumulus and stratocumulus layers. The PDF method is sufficiently general to adequately simulate these five deep, shallow, and stratiform cloud cases with a single equation set. This raises hopes that it may be possible in the future, with further refinements at coarse time step and grid spacing, to parameterize all cloud types in a large-scale model in a unified way.« less

  4. Parameterizing deep convection using the assumed probability density function method

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

    Storer, R. L.; Griffin, B. M.; Hft, J.; Weber, J. K.; Raut, E.; Larson, V. E.; Wang, M.; Rasch, P. J.

    2015-01-06

    Due to their coarse horizontal resolution, present-day climate models must parameterize deep convection. This paper presents single-column simulations of deep convection using a probability density function (PDF) parameterization. The PDF parameterization predicts the PDF of subgrid variability of turbulence, clouds, and hydrometeors. That variability is interfaced to a prognostic microphysics scheme using a Monte Carlo sampling method.The PDF parameterization is used to simulate tropical deep convection, the transition from shallow to deep convection over land, and midlatitude deep convection. These parameterized single-column simulations are compared with 3-D reference simulations. The agreement is satisfactory except when the convective forcing is weak.moreThe same PDF parameterization is also used to simulate shallow cumulus and stratocumulus layers. The PDF method is sufficiently general to adequately simulate these five deep, shallow, and stratiform cloud cases with a single equation set. This raises hopes that it may be possible in the future, with further refinements at coarse time step and grid spacing, to parameterize all cloud types in a large-scale model in a unified way.less

  5. Completion Report for Well Cluster ER-6-1

    SciTech Connect (OSTI)

    Bechtel Nevada

    2004-10-01

    Well Cluster ER-6-1 was constructed for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Division at the Nevada Test Site, Nye County, Nevada. This work was initiated as part of the Groundwater Characterization Project, now known as the Underground Test Area Project. The well cluster is located in southeastern Yucca Flat. Detailed lithologic descriptions with stratigraphic assignments for Well Cluster ER-6-1 are included in this report. These are based on composite drill cuttings collected every 3 meters and conventional core samples taken below 639 meters, supplemented by geophysical log data. Detailed petrographic, chemical, and mineralogical studies of rock samples were conducted on 11 samples to resolve complex interrelationships between several of the Tertiary tuff units. Additionally, paleontological analyses by the U.S. Geological Survey confirmed the stratigraphic assignments below 539 meters within the Paleozoic sedimentary section. All three wells in the Well ER-6-1 cluster were drilled within the Quaternary and Tertiary alluvium section, the Tertiary volcanic section, and into the Paleozoic sedimentary section.

  6. 2011 Clusters, Nanocrystals & Nanostructures Gordon Research Conference

    SciTech Connect (OSTI)

    Lai-Sheng Wang

    2011-07-29

    Small particles have been at the heart of nanoscience since the birth of the field and now stand ready to make significant contributions to the big challenges of energy, health and sustainability. Atomic clusters show exquisite size-dependent electronic and magnetic properties and offer a new level of control in catalyses, sensors and biochips; functionalised nanocrystals offer remarkable optical properties and diverse applications in electronic devices, solar energy, and therapy. Both areas are complemented by a raft of recent advances in fabrication, characterization, and performance of a diversity of nanomaterials from the single atom level to nanowires, nanodevices, and biologically-inspired nanosystems. The goal of the 2011 Gordon Conference is thus to continue and enhance the interdisciplinary tradition of this series and discuss the most recent advances, fundamental scientific questions, and emerging applications of clusters, nanocrystals, and nanostructures. A single conference covering all aspects of nanoscience from fundamental issues to applications has the potential to create new ideas and stimulate cross fertilization. The meeting will therefore provide a balance among the three sub-components of the conference, true to its title, with a selection of new topics added to reflect rapid advances in the field. The open atmosphere of a Gordon conference, emphasizing the presentation of unpublished results and extensive discussions, is an ideal home for this rapidly developing field and will allow all participants to enjoy a valuable and stimulating experience. Historically, this Gordon conference has been oversubscribed, so we encourage all interested researchers from academia, industry, and government institutions to apply as early as possible. We also encourage all attendees to submit their latest results for presentation at the poster sessions. We anticipate that several posters will be selected for 'hot topic' oral presentations. Given the important

  7. KECK/MOSFIRE SPECTROSCOPIC CONFIRMATION OF A VIRGO-LIKE CLUSTER ANCESTOR AT z = 2.095

    SciTech Connect (OSTI)

    Yuan, Tiantian; Kewley, Lisa J.; Nanayakkara, Themiya; Kacprzak, Glenn G.; Glazebrook, Karl; Tran, Kim-Vy H.; Tomczak, Adam R.; Spitler, Lee R.; Poole, Gregory B.; Labbé, Ivo; Straatman, Caroline M. S.

    2014-11-01

    We present spectroscopic confirmation of a galaxy cluster at z = 2.095 in the COSMOS field. This galaxy cluster was first reported in the ZFOURGE survey as harboring evolved massive galaxies using photometric redshifts derived with deep near-infrared (NIR) medium-band filters. We obtain medium-resolution (R ∼ 3600) NIR spectroscopy with MOSFIRE on the Keck 1 telescope and secure 180 redshifts in a 12' × 12' region. We find a prominent spike of 57 galaxies at z = 2.095 corresponding to the galaxy cluster. The cluster velocity dispersion is measured to be σ{sub v1D}  =  552 ± 52 km s{sup –1}. This is the first study of a galaxy cluster in this redshift range (z ≳ 2.0) with the combination of spectral resolution (∼26 km s{sup –1}) and the number of confirmed members (>50) needed to impose a meaningful constraint on the cluster velocity dispersion and map its members over a large field of view. Our ΛCDM cosmological simulation suggests that this cluster will most likely evolve into a Virgo-like cluster with M {sub vir} = 10{sup 14.4} {sup ±} {sup 0.3} M {sub ☉} (68% confidence) at z ∼ 0. The theoretical probability of finding such a cluster is ∼4%. Our results demonstrate the feasibility of studying galaxy clusters at z > 2 in the same detailed manner using multi-object NIR spectrographs as has been done in the optical in lower-redshift clusters.

  8. A uvbyCaH? analysis of the old open cluster, NGC 6819

    SciTech Connect (OSTI)

    Anthony-Twarog, Barbara J.; Twarog, Bruce A.; Deliyannis, Constantine P. E-mail: btwarog@ku.edu

    2014-09-01

    NGC 6819 is a richly populated, older open cluster situated within the Kepler field. A CCD survey of the cluster on the uvbyCaH? system, coupled with proper-motion membership, has been used to isolate 382 highly probable, single-star unevolved main-sequence members over a 20' field centered on the cluster. From 278 F dwarfs with high precision photometry in all indices, a mean reddening of E(b y) = 0.117 0.005 or E(B V) = 0.160 0.007 is derived, where the standard errors of the mean include both internal errors and the photometric zero-point uncertainty. With the reddening fixed, the metallicity derived from the same 278 stars is [Fe/H] = 0.116 0.101 from m {sub 1} and 0.055 0.033 from hk, for a weighted average of [Fe/H] = 0.06 0.04, where the quoted standard errors of the mean include the internal errors from the photometric scatter plus the uncertainty in the photometric zero points. If metallicity is derived using individual reddening values for each star to account for potential reddening variation across the face of the cluster, the analogous result is unchanged. The cluster members at the turnoff of the color-magnitude diagram are used to test and confirm the recently discovered variation in reddening across the face of the cluster, with a probable range in the variation of ?E(B V) = 0.045 0.015. With the slightly higher reddening and lower [Fe/H] compared to commonly adopted values, isochrone fitting leads to an age of 2.3 0.2 Gyr for an apparent modulus of (m M) = 12.40 0.12.

  9. Probability of pipe fracture in the primary coolant loop of a PWR Plant. Volume 7. System failure probability analysis. Load Combination Program Project I final report

    SciTech Connect (OSTI)

    George, L.; Mensing, R.

    1981-06-01

    This volume describes the computational methodology used to estimate the probability of a simultaneous occurrence of an earthquake and a primary coolant loop pipe fracture caused directly by an earthquake for a pressurized water reactor. Point estimates of this probability, based on a simulation experiment, and the probabilities of related events are included. Simulation is used to estimate weld fracture probabilities conditional on a crack initially existing and an earthquake of specified intensity occurring at a specified time in the life of the plant. These estimates are combined with probabilities associated with the occurrence of an earthquake and the existence of a crack to obtain an estimate of the probability of simultaneous earthquake and pipe fracture for the entire primary coolant loop piping system. A point estimate of probability, as outlined in this volume, does not fully take into consideration all of the uncertainties associated with an analysis of this type. Uncertainty analysis, confidence interval estimates, and sensitivity measures better reflect potential uncertainties. These topics are discussed. Finally, a discussion of the use of a risk-based, rather than a probability-based, decision criterion for deciding whether to decouple is included. 13 refs., 7 figs., 6 tabs.

  10. ATCOM: Automatically Tuned Collective Communication System for SMP Clusters

    SciTech Connect (OSTI)

    Meng-Shiou Wu

    2005-12-17

    Conventional implementations of collective communications are based on point-to-point communications, and their optimizations have been focused on efficiency of those communication algorithms. However, point-to-point communications are not the optimal choice for modern computing clusters of SMPs due to their two-level communication structure. In recent years, a few research efforts have investigated efficient collective communications for SMP clusters. This dissertation is focused on platform-independent algorithms and implementations in this area. There are two main approaches to implementing efficient collective communications for clusters of SMPs: using shared memory operations for intra-node communications, and overlapping inter-node/intra-node communications. The former fully utilizes the hardware based shared memory of an SMP, and the latter takes advantage of the inherent hierarchy of the communications within a cluster of SMPs. Previous studies focused on clusters of SMP from certain vendors. However, the previously proposed methods are not portable to other systems. Because the performance optimization issue is very complicated and the developing process is very time consuming, it is highly desired to have self-tuning, platform-independent implementations. As proven in this dissertation, such an implementation can significantly out-perform the other point-to-point based portable implementations and some platform-specific implementations. The dissertation describes in detail the architecture of the platform-independent implementation. There are four system components: shared memory-based collective communications, overlapping mechanisms for inter-node and intra-node communications, a prediction-based tuning module and a micro-benchmark based tuning module. Each component is carefully designed with the goal of automatic tuning in mind.

  11. BULLET CLUSTER: A CHALLENGE TO {Lambda}CDM COSMOLOGY

    SciTech Connect (OSTI)

    Lee, Jounghun; Komatsu, Eiichiro

    2010-07-20

    To quantify how rare the bullet-cluster-like high-velocity merging systems are in the standard {Lambda} cold dark matter (CDM) cosmology, we use a large-volume (27 h {sup -3} Gpc{sup 3}) cosmological N-body MICE simulation to calculate the distribution of infall velocities of subclusters around massive main clusters. The infall velocity distribution is given at (1-3)R{sub 200} of the main cluster (where R{sub 200} is similar to the virial radius), and thus it gives the distribution of realistic initial velocities of subclusters just before collision. These velocities can be compared with the initial velocities used by the non-cosmological hydrodynamical simulations of 1E0657-56 in the literature. The latest parameter search carried out by Mastropietro and Burkert has shown that an initial velocity of 3000 km s{sup -1} at about 2R{sub 200} is required to explain the observed shock velocity, X-ray brightness ratio of the main and subcluster, X-ray morphology of the main cluster, and displacement of the X-ray peaks from the mass peaks. We show that such a high infall velocity at 2R{sub 200} is incompatible with the prediction of a {Lambda}CDM model: the probability of finding 3000 km s{sup -1} in (2-3)R{sub 200} is between 3.3 x 10{sup -11} and 3.6 x 10{sup -9}. A lower velocity, 2000 km s{sup -1} at 2R{sub 200}, is also rare, and moreover, Mastropietro and Burkert have shown that such a low initial velocity does not reproduce the X-ray brightness ratio of the main and subcluster or morphology of the main cluster. Therefore, we conclude that the existence of 1E0657-56 is incompatible with the prediction of a {Lambda}CDM model, unless a lower infall velocity solution for 1E0657-56 with {approx}<1800 km s{sup -1} at 2R{sub 200} is found.

  12. Toward understanding environmental effects in SDSS clusters

    SciTech Connect (OSTI)

    Einasto, Jaan; Tago, E.; Einasto, M.; Saar, E.; Suhhonenko, I.; Heinamaki, P.; Hutsi, G.; Tucker, D.L.; /Fermilab

    2004-11-01

    We find clusters and superclusters of galaxies using the Data Release 1 of the Sloan Digital Sky Survey. We determine the luminosity function of clusters and find that clusters in a high-density environment have a luminosity a factor of {approx}5 higher than in a low-density environment. We also study clusters and superclusters in numerical simulations. Simulated clusters in a high-density environment are also more massive than those in a low-density environment. Comparison of the density distribution at various epochs in simulations shows that in large low-density regions (voids) dynamical evolution is very slow and stops at an early epoch. In contrast, in large regions of higher density (superclusters) dynamical evolution starts early and continues until the present; here particles cluster early, and by merging of smaller groups very rich systems of galaxies form.

  13. JLab Cluster Tops 100 Teraflops | Jefferson Lab

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

    Cluster Tops 100 Teraflops JLab Cluster Tops 100 Teraflops NEWPORT NEWS, VA, Oct. 14 - The fastest computer system in Hampton Roads has booted up with more than 100 Teraflops of processing power. Located at the Department of Energy's Thomas Jefferson National Accelerator Facility, the cluster computer system was recently upgraded with video game components to assist scientists in modeling the smallest bits of matter in the universe. "Our resources crossed 100 Teraflops of sustained

  14. Multiphoton ionization of large water clusters

    SciTech Connect (OSTI)

    Apicella, B.; Li, X.; Passaro, M.; Spinelli, N.; Wang, X.

    2014-05-28

    Water clusters are multimers of water molecules held together by hydrogen bonds. In the present work, multiphoton ionization in the UV range coupled with time of flight mass spectrometry has been applied to water clusters with up to 160 molecules in order to obtain information on the electronic states of clusters of different sizes up to dimensions that can approximate the bulk phase. The dependence of ion intensities of water clusters and their metastable fragments produced by laser ionization at 355 nm on laser power density indicates a (3+1)-photon resonance-enhanced multiphoton ionization process. It also explains the large increase of ionization efficiency at 355 nm compared to that at 266 nm. Indeed, it was found, by applying both nanosecond and picosecond laser ionization with the two different UV wavelengths, that no water cluster sequences after n = 9 could be observed at 266 nm, whereas water clusters up to m/z 2000 Th in reflectron mode and m/z 3000 Th in linear mode were detected at 355 nm. The agreement between our findings on clusters of water, especially true in the range with n > 10, and reported data for liquid water supports the hypothesis that clusters above a critical dimension can approximate the liquid phase. It should thus be possible to study clusters just above 10 water molecules, for getting information on the bulk phase structure.

  15. Cluster Team Saffron Amanda Bonnie Zach Fuerst

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

    a Lustre Cluster Team Saffron Amanda Bonnie Zach Fuerst Thomas Stitt yaaaasss (Improving and Tracing Lustre Metadata) Overview Motivation Configuration Tracing Metadata...

  16. MCS Large Cluster Systems Software Toolkit

    Energy Science and Technology Software Center (OSTI)

    2002-11-01

    This package contains a number of systems utilities for managing a set of computers joined in a "cluster". The utilities assist a team of systems administrators in managing the cluster by automating routine tasks, centralizing information, and monitoring individual computers within the cluster. Included in the toolkit are scripts used to boot a computer from a floppy, a program to turn on and off the power to a system, and a system for using amore » database to organize cluster information.« less

  17. BTime A Clock Synchronization Tool For Linux Clusters

    Energy Science and Technology Software Center (OSTI)

    2004-10-22

    BTime software synchronizes the system clocks on Linux computers that can communicate on a network. Primarily intended for Linux computers that form a cluster, BTime ensures that all computers in the cluster have approximately the same time (usually within microseconds). In operation, a BTime server broadcasts target times every second. All BTime clients filter timing data and apply local time corrections synchronously at multiples of 64 seconds. Bayesian estimation of target time errors feeds amore » Kalman filter which estimates local errors in time, clock drift, and wander rates. Server dock adjustments are detected and compensated, thus reducing filter convergence time. Low probability events (e.g. significant time changes) are handled through heuristics also designed to reduce filter convergence time. Normal BTime corrects dock differences, while another version of BTime that only tracks clock differences can be used for measurements. In authors test lasting four days, BTime delivered estimated dock synchronization within 10 microseconds with 99.75% confidence. Standard deviation of the estimated clock offset is typically 2-3 microseconds, even over busy multi-hop networks. These results are about 100 times better than published results for Network Time Protocol (NTP).« less

  18. BTime A Clock Synchronization Tool For Linux Clusters

    SciTech Connect (OSTI)

    Loncaric, Josip

    2004-10-22

    BTime software synchronizes the system clocks on Linux computers that can communicate on a network. Primarily intended for Linux computers that form a cluster, BTime ensures that all computers in the cluster have approximately the same time (usually within microseconds). In operation, a BTime server broadcasts target times every second. All BTime clients filter timing data and apply local time corrections synchronously at multiples of 64 seconds. Bayesian estimation of target time errors feeds a Kalman filter which estimates local errors in time, clock drift, and wander rates. Server dock adjustments are detected and compensated, thus reducing filter convergence time. Low probability events (e.g. significant time changes) are handled through heuristics also designed to reduce filter convergence time. Normal BTime corrects dock differences, while another version of BTime that only tracks clock differences can be used for measurements. In authors test lasting four days, BTime delivered estimated dock synchronization within 10 microseconds with 99.75% confidence. Standard deviation of the estimated clock offset is typically 2-3 microseconds, even over busy multi-hop networks. These results are about 100 times better than published results for Network Time Protocol (NTP).

  19. Merger signatures in the galaxy cluster A98

    SciTech Connect (OSTI)

    Paterno-Mahler, R.; Blanton, E. L.; Randall, S. W.; Bulbul, E.; Andrade-Santos, F.; Jones, C.; Murray, S.; Johnson, R. E. E-mail: eblanton@bu.edu E-mail: ebulbul@head.cfa.harvard.edu E-mail: cjones@cfa.harvard.edu E-mail: rjohnson@gettysburg.edu

    2014-08-20

    We present results from Chandra and XMM-Newton observations of Abell 98 (A98), a galaxy cluster with three major components: a relatively bright subcluster to the north (A98N), a disturbed subcluster to the south (A98S), and a fainter subcluster to the far south (A98SS). We find evidence for surface brightness and temperature asymmetries in A98N consistent with a shock-heated region to the south, which could be created by an early stage merger between A98N and A98S. Deeper observations are required to confirm this result. We also find that A98S has an asymmetric core temperature structure, likely due to a separate ongoing merger. Evidence for this is also seen in optical data. A98S hosts a wide-angle tail radio source powered by a central active galactic nucleus (AGN). We find evidence for a cavity in the intracluster medium that has been evacuated by one of the radio lobes, suggesting that AGN feedback is operating in this system. Examples of cavities in non-cool core clusters are relatively rare. The three subclusters lie along a line in projection, suggesting the presence of a large-scale filament. We observe emission along the filament between A98N and A98S, and a surface brightness profile shows emission consistent with the overlap of the subcluster extended gas halos. We find the temperature of this region is consistent with the temperature of the gas at similar radii outside this bridge region. Lastly, we examine the cluster dynamics using optical data. We conclude A98N and A98S are likely bound to one another with a 67% probability, while A98S and A98SS are not bound at a high level of significance.

  20. 2009 Clusters, Nanocrystals & Nanostructures GRC

    SciTech Connect (OSTI)

    Lai-Sheng Wang

    2009-07-19

    For over thirty years, this Gordon Conference has been the premiere meeting for the field of cluster science, which studies the phenomena that arise when matter becomes small. During its history, participants have witnessed the discovery and development of many novel materials, including C60, carbon nanotubes, semiconductor and metal nanocrystals, and nanowires. In addition to addressing fundamental scientific questions related to these materials, the meeting has always included a discussion of their potential applications. Consequently, this conference has played a critical role in the birth and growth of nanoscience and engineering. The goal of the 2009 Gordon Conference is to continue the forward-looking tradition of this meeting and discuss the most recent advances in the field of clusters, nanocrystals, and nanostructures. As in past meetings, this will include new topics that broaden the field. In particular, a special emphasis will be placed on nanomaterials related to the efficient use, generation, or conversion of energy. For example, we anticipate presentations related to batteries, catalysts, photovoltaics, and thermoelectrics. In addition, we expect to address the controversy surrounding carrier multiplication with a session in which recent results addressing this phenomenon will be discussed and debated. The atmosphere of the conference, which emphasizes the presentation of unpublished results and lengthy discussion periods, ensures that attendees will enjoy a valuable and stimulating experience. Because only a limited number of participants are allowed to attend this conference, and oversubscription is anticipated, we encourage all interested researchers from academia, industry, and government institutions to apply as early as possible. An invitation is not required. We also encourage all attendees to submit their latest results for presentation at the poster sessions. We anticipate that several posters will be selected for 'hot topic' oral

  1. Lattice QCD production on commodity clusters at Fermilab

    SciTech Connect (OSTI)

    D. Holmgren et al.

    2003-09-30

    We describe the construction and results to date of Fermilab's three Myrinet-networked lattice QCD production clusters (an 80-node dual Pentium III cluster, a 48-node dual Xeon cluster, and a 128-node dual Xeon cluster). We examine a number of aspects of performance of the MILC lattice QCD code running on these clusters.

  2. Investigations of Galaxy Clusters Using Gravitational Lensing

    SciTech Connect (OSTI)

    Wiesner, Matthew P.

    2014-08-01

    In this dissertation, we discuss the properties of galaxy clusters that have been determined using strong and weak gravitational lensing. A galaxy cluster is a collection of galaxies that are bound together by the force of gravity, while gravitational lensing is the bending of light by gravity. Strong lensing is the formation of arcs or rings of light surrounding clusters and weak lensing is a change in the apparent shapes of many galaxies. In this work we examine the properties of several samples of galaxy clusters using gravitational lensing. In Chapter 1 we introduce astrophysical theory of galaxy clusters and gravitational lensing. In Chapter 2 we examine evidence from our data that galaxy clusters are more concentrated than cosmology would predict. In Chapter 3 we investigate whether our assumptions about the number of galaxies in our clusters was valid by examining new data. In Chapter 4 we describe a determination of a relationship between mass and number of galaxies in a cluster at higher redshift than has been found before. In Chapter 5 we describe a model of the mass distribution in one of the ten lensing systems discovered by our group at Fermilab. Finally in Chapter 6 we summarize our conclusions.

  3. Reinvestigating the clusters Koposov 1 and 2

    SciTech Connect (OSTI)

    Paust, Nathaniel; Wilson, Danielle; Van Belle, Gerard

    2014-07-01

    We investigate the fundamental parameters of age, distance, and mass function slope for the poorly studied clusters Koposov 1 and Koposov 2. These clusters were discovered recently and tentatively classified as globular clusters. Using the Large Monolithic Imager on Lowell Observatory's Discovery Channel Telescope, we present photometry extending to V = 25, three to four magnitudes below the main sequence turnoffs for the clusters. We find the clusters have tidal radii of 15 pc and 10.7 pc and distances of 34.9 kpc and 33.3 kpc for Koposov 1 and Koposov 2, respectively. Studying the stellar content of the clusters, we use completeness-corrected star counts to reveal extremely faint total magnitudes of 2.01 and 0.03 in V, and steep Salpeter-like present-day mass functions. Finally, we show that the spatial positions of the clusters agree well with the position of the Sagittarius stream and conclude that these two objects are open clusters removed from the Sagittarius galaxy.

  4. 300 Area - Hanford Site

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

    300 Area 324 Building 325 Building 400 AreaFast Flux Test Facility 618-10 and 618-11 Burial Grounds 700 Area B Plant B Reactor C Reactor Canister Storage Building and Interim ...

  5. 200 Area - Hanford Site

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

    300 Area 324 Building 325 Building 400 AreaFast Flux Test Facility 618-10 and 618-11 Burial Grounds 700 Area B Plant B Reactor C Reactor Canister Storage Building and Interim ...

  6. 700 Area - Hanford Site

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

    300 Area 324 Building 325 Building 400 AreaFast Flux Test Facility 618-10 and 618-11 Burial Grounds 700 Area B Plant B Reactor C Reactor Canister Storage Building and Interim ...

  7. Sweet Surface Area

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

    Sweet Surface Area Sweet Surface Area Create a delicious root beer float and learn sophisticated science concepts at the same time. Sweet Surface Area Science is all around us, so ...

  8. Suppression of alpha formation probability around the N = 126 shell closure

    SciTech Connect (OSTI)

    Qi, Chong; Liotta, R. J.; Wyss, R.; Andreyev, A. N.; Huyse, M.; Van Duppen, P.

    2011-10-28

    {alpha} formation amplitudes extracted from experimental data are presented and an abrupt change around the N = 126 shell closure is noted. It is explained as a sudden hindrance of the clustering of nucleons. The clustering induced by the pairing mode acting upon the four nucleons is inhibited if the configuration space does not allow a proper manifestation of the pairing collectivity.

  9. Bipartite graph partitioning and data clustering

    SciTech Connect (OSTI)

    Zha, Hongyuan; He, Xiaofeng; Ding, Chris; Gu, Ming; Simon, Horst D.

    2001-05-07

    Many data types arising from data mining applications can be modeled as bipartite graphs, examples include terms and documents in a text corpus, customers and purchasing items in market basket analysis and reviewers and movies in a movie recommender system. In this paper, the authors propose a new data clustering method based on partitioning the underlying biopartite graph. The partition is constructed by minimizing a normalized sum of edge weights between unmatched pairs of vertices of the bipartite graph. They show that an approximate solution to the minimization problem can be obtained by computing a partial singular value decomposition (SVD) of the associated edge weight matrix of the bipartite graph. They point out the connection of their clustering algorithm to correspondence analysis used in multivariate analysis. They also briefly discuss the issue of assigning data objects to multiple clusters. In the experimental results, they apply their clustering algorithm to the problem of document clustering to illustrate its effectiveness and efficiency.

  10. Strategic Focus Areas

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

    Strategic Focus Areas Lockheed Martin on behalf of Sandia National Laboratories will consider grant requests that best support the Corporation's strategic focus areas and reflect ...

  11. AREA 5 RWMS CLOSURE

    National Nuclear Security Administration (NNSA)

    153 CLOSURE STRATEGY NEVADA TEST SITE AREA 5 RADIOACTIVE WASTE MANAGEMENT SITE Revision 0 ... Closure Strategy Nevada Test Site Area 5 Radioactive Waste Management ...

  12. Galaxy cluster baryon fractions revisited

    SciTech Connect (OSTI)

    Gonzalez, Anthony H.; Sivanandam, Suresh; Zabludoff, Ann I.; Zaritsky, Dennis

    2013-11-20

    We measure the baryons contained in both the stellar and hot-gas components for 12 galaxy clusters and groups at z ∼ 0.1 with M = 1-5 × 10{sup 14} M {sub ☉}. This paper improves upon our previous work through the addition of XMM-Newton X-ray data, enabling measurements of the total mass and masses of each major baryonic component—intracluster medium, intracluster stars, and stars in galaxies—for each system. We recover a mean relation for the stellar mass versus halo mass, M{sub ⋆}∝M{sub 500}{sup −0.52±0.04}, that is 1σ shallower than in our previous result. We confirm that the partitioning of baryons between the stellar and hot-gas components is a strong function of M {sub 500}; the fractions of total mass in stars and X-ray gas within a sphere of radius r {sub 500} scale as f{sub ⋆}∝M{sub 500}{sup −0.45±0.04} and f{sub gas}∝M{sub 500}{sup 0.26±0.03}, respectively. We also confirm that the combination of the brightest cluster galaxy and intracluster stars is an increasingly important contributor to the stellar baryon budget in lower halo masses. Studies that fail to fully account for intracluster stars typically underestimate the normalization of the stellar baryon fraction versus M {sub 500} relation by ∼25%. Our derived stellar baryon fractions are also higher, and the trend with halo mass weaker, than those derived from recent halo occupation distribution and abundance matching analyses. One difference from our previous work is the weak, but statistically significant, dependence here of the total baryon fraction upon halo mass: f{sub bary}∝M{sub 500}{sup 0.16±0.04}. For M {sub 500} ≳ 2 × 10{sup 14}, the total baryon fractions within r {sub 500} are on average 18% below the universal value from the seven year Wilkinson Microwave Anisotropy Probe (WMAP) analysis, or 7% below for the cosmological parameters from the Planck analysis. In the latter case, the difference between the universal value and cluster baryon fractions is

  13. NREL: Measurements and Characterization - Surface Analysis Cluster Tool

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

    Surface Analysis Cluster Tool Floor plan showing where surface analysis cluster equipment sits. Schematic diagram of the surface analysis cluster tool. Photograph of the Surface Analysis Cluster Tool The surface analysis cluster tool was designed and built by NREL for the in-situ study of surface and chemical changes. Residing in our new Science and Technology Facility (S&TF), is the surface analysis cluster tool that the National Renewable Energy Laboratory recently designed and built for

  14. 100 Area - Hanford Site

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

    00 Area About Us About Hanford Cleanup Hanford History Hanford Site Wide Programs Contact Us 100 Area 118-K-1 Burial Ground 200 Area 222-S Laboratory 242-A Evaporator 300 Area 324 Building 325 Building 400 Area/Fast Flux Test Facility 618-10 and 618-11 Burial Grounds 700 Area B Plant B Reactor C Reactor Canister Storage Building and Interim Storage Area Canyon Facilities Cold Test Facility D and DR Reactors Effluent Treatment Facility Environmental Restoration Disposal Facility F Reactor H

  15. The C4 clustering algorithm: Clusters of galaxies in the Sloan Digital Sky Survey

    SciTech Connect (OSTI)

    Miller, Christopher J.; Nichol, Robert; Reichart, Dan; Wechsler, Risa H.; Evrard, August; Annis, James; McKay, Timothy; Bahcall, Neta; Bernardi, Mariangela; Boehringer, Hans; Connolly, Andrew; Goto, Tomo; Kniazev, Alexie; Lamb, Donald; Postman, Marc; Schneider, Donald; Sheth, Ravi; Voges, Wolfgang; /Cerro-Tololo InterAmerican Obs. /Portsmouth U., ICG /North Carolina U. /Chicago U., Astron. Astrophys. Ctr. /Chicago U., EFI /Michigan U. /Fermilab /Princeton U. Observ. /Garching, Max Planck Inst., MPE /Pittsburgh U. /Tokyo U., ICRR /Baltimore, Space Telescope Sci. /Penn State U. /Chicago U. /Stavropol, Astrophys. Observ. /Heidelberg, Max Planck Inst. Astron. /INI, SAO

    2005-03-01

    We present the ''C4 Cluster Catalog'', a new sample of 748 clusters of galaxies identified in the spectroscopic sample of the Second Data Release (DR2) of the Sloan Digital Sky Survey (SDSS). The C4 cluster-finding algorithm identifies clusters as overdensities in a seven-dimensional position and color space, thus minimizing projection effects that have plagued previous optical cluster selection. The present C4 catalog covers {approx}2600 square degrees of sky and ranges in redshift from z = 0.02 to z = 0.17. The mean cluster membership is 36 galaxies (with redshifts) brighter than r = 17.7, but the catalog includes a range of systems, from groups containing 10 members to massive clusters with over 200 cluster members with redshifts. The catalog provides a large number of measured cluster properties including sky location, mean redshift, galaxy membership, summed r-band optical luminosity (L{sub r}), velocity dispersion, as well as quantitative measures of substructure and the surrounding large-scale environment. We use new, multi-color mock SDSS galaxy catalogs, empirically constructed from the {Lambda}CDM Hubble Volume (HV) Sky Survey output, to investigate the sensitivity of the C4 catalog to the various algorithm parameters (detection threshold, choice of passbands and search aperture), as well as to quantify the purity and completeness of the C4 cluster catalog. These mock catalogs indicate that the C4 catalog is {approx_equal}90% complete and 95% pure above M{sub 200} = 1 x 10{sup 14} h{sup -1}M{sub {circle_dot}} and within 0.03 {le} z {le} 0.12. Using the SDSS DR2 data, we show that the C4 algorithm finds 98% of X-ray identified clusters and 90% of Abell clusters within 0.03 {le} z {le} 0.12. Using the mock galaxy catalogs and the full HV dark matter simulations, we show that the L{sub r} of a cluster is a more robust estimator of the halo mass (M{sub 200}) than the galaxy line-of-sight velocity dispersion or the richness of the cluster. However, if we

  16. Analysis of Molecular Clusters in Simulations of Lithium-Ion...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Analysis of Molecular Clusters in Simulations of Lithium-Ion Battery Electrolytes. Citation Details In-Document Search Title: Analysis of Molecular Clusters in ...

  17. Three-dimensional Modeling of Fracture Clusters in Geothermal...

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

    Reservoirs Three-dimensional Modeling of Fracture Clusters in Geothermal Reservoirs ... More Documents & Publications Three-dimensional Modeling of Fracture Clusters in ...

  18. Three-dimensional Modeling of Fracture Clusters in Geeothermal...

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

    Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs Three-dimensional Modeling of ...

  19. Reactive Molecular Simulations of Protonation of Water Clusters...

    Office of Scientific and Technical Information (OSTI)

    of Water Clusters and Depletion of Acidity in H-ZSM-5 Zeolite Citation Details In-Document Search Title: Reactive Molecular Simulations of Protonation of Water Clusters ...

  20. Toward Understanding the Microscopic Origin of Nuclear Clustering...

    Office of Scientific and Technical Information (OSTI)

    Toward Understanding the Microscopic Origin of Nuclear Clustering Citation Details In-Document Search Title: Toward Understanding the Microscopic Origin of Nuclear Clustering Open...

  1. Formation of Compact Clusters from High Resolution Hybrid Cosmological...

    Office of Scientific and Technical Information (OSTI)

    Formation of Compact Clusters from High Resolution Hybrid Cosmological Simulations Citation Details In-Document Search Title: Formation of Compact Clusters from High Resolution ...

  2. Offsets between the X-ray and the Sunyaev-Zel'Dovich-effect peaks in merging galaxy clusters and their cosmological implications

    SciTech Connect (OSTI)

    Zhang, Congyao; Yu, Qingjuan; Lu, Youjun

    2014-12-01

    Observations reveal that the peaks of the X-ray map and the Sunyaev-Zel'dovich (SZ) effect map of some galaxy clusters are offset from each other. In this paper, we perform a set of hydrodynamical simulations of mergers of two galaxy clusters to investigate the spatial offset between the maxima of the X-ray and the SZ surface brightness of the merging clusters. We find that significantly large SZ-X-ray offsets (>100 kpc) can be produced during the major mergers of galaxy clusters (with mass > 1 10{sup 14} M {sub ?}). The significantly large offsets are mainly caused by a 'jump effect' that occurs between the primary and secondary pericentric passages of the two merging clusters, during which the X-ray peak may jump to the densest gas region located near the center of the small cluster, but the SZ peak remains near the center of the large one. Our simulations show that merging systems with higher masses and larger initial relative velocities may result in larger offset sizes and longer offset time durations; and only nearly head-on mergers are likely to produce significantly large offsets. We further investigate the statistical distribution of the SZ-X-ray offset sizes and find that (1) the number distribution of the offset sizes is bimodal with one peak located at low offsets ?0 and the other at large offsets ?350-450 h {sup 1} kpc, but the objects with intermediate offsets are scarce; and (2) the probabilities of the clusters in the mass range higher than 2 10{sup 14} h {sup 1} M {sub ?} that have offsets larger than 20, 50, 200, 300, and 500 h {sup 1} kpc are 34.0%, 11.1%, 8.0%, 6.5%, and 2.0%, respectively, at z = 0.7. The probability is sensitive to the underlying pairwise velocity distribution and the merger rate of clusters. We suggest that the SZ-X-ray offsets provide a probe to the cosmic velocity fields on the cluster scale and the cluster merger rate, and future observations on the SZ-X-ray offsets for a large number of clusters may put strong

  3. Hα star formation rates of z > 1 galaxy clusters in the IRAC shallow cluster survey

    SciTech Connect (OSTI)

    Zeimann, Gregory R.; Stanford, S. A.; Brodwin, Mark; Gonzalez, Anthony H.; Mancone, Conor; Snyder, Gregory F.; Stern, Daniel; Eisenhardt, Peter; Dey, Arjun; Moustakas, John

    2013-12-20

    We present Hubble Space Telescope near-IR spectroscopy for 18 galaxy clusters at 1.0 Cluster Survey. We use Wide Field Camera 3 grism data to spectroscopically identify Hα emitters in both the cores of galaxy clusters as well as in field galaxies. We find a large cluster-to-cluster scatter in the star formation rates within a projected radius of 500 kpc, and many of our clusters (∼60%) have significant levels of star formation within a projected radius of 200 kpc. A stacking analysis reveals that dust reddening in these star-forming galaxies is positively correlated with stellar mass and may be higher in the field than the cluster at a fixed stellar mass. This may indicate a lower amount of gas in star-forming cluster galaxies than in the field population. Also, Hα equivalent widths of star-forming galaxies in the cluster environment are still suppressed below the level of the field. This suppression is most significant for lower mass galaxies (log M {sub *} < 10.0 M {sub ☉}). We therefore conclude that environmental effects are still important at 1.0 clusters with log M {sub *} ≲ 10.0 M {sub ☉}.

  4. Method for assaying clustered DNA damages

    DOE Patents [OSTI]

    Sutherland, Betsy M.

    2004-09-07

    Disclosed is a method for detecting and quantifying clustered damages in DNA. In this method, a first aliquot of the DNA to be tested for clustered damages with one or more lesion-specific cleaving reagents under conditions appropriate for cleavage of the DNA to produce single-strand nicks in the DNA at sites of damage lesions. The number average molecular length (Ln) of double stranded DNA is then quantitatively determined for the treated DNA. The number average molecular length (Ln) of double stranded DNA is also quantitatively determined for a second, untreated aliquot of the DNA. The frequency of clustered damages (.PHI..sub.c) in the DNA is then calculated.

  5. Microsoft Word - Fe-S_Clusters

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

    April 2010 Figure 1. Top: overall ribbon and surface representation of the x-ray crystal structure of [FeFe]-hydrogenase HydA ΔEFG . Loop regions important for the cluster insertion process are colored green. Bottom: Ball and stick representation of the active site of HydA ΔEFG at which a [4Fe-4S] cluster is present. Coloring scheme: rust, iron; orange, sulfur; gray, carbon; red, oxygen; blue, nitrogen. Assembly and Evolution of Complex Fe-S Clusters as Revealed by X-ray Crystallography

  6. The transition probability and the probability for the left-most particle's position of the q-totally asymmetric zero range process

    SciTech Connect (OSTI)

    Korhonen, Marko; Lee, Eunghyun

    2014-01-15

    We treat the N-particle zero range process whose jumping rates satisfy a certain condition. This condition is required to use the Bethe ansatz and the resulting model is the q-boson model by Sasamoto and Wadati [Exact results for one-dimensional totally asymmetric diffusion models, J. Phys. A 31, 60576071 (1998)] or the q-totally asymmetric zero range process (TAZRP) by Borodin and Corwin [Macdonald processes, Probab. Theory Relat. Fields (to be published)]. We find the explicit formula of the transition probability of the q-TAZRP via the Bethe ansatz. By using the transition probability we find the probability distribution of the left-most particle's position at time t. To find the probability for the left-most particle's position we find a new identity corresponding to identity for the asymmetric simple exclusion process by Tracy and Widom [Integral formulas for the asymmetric simple exclusion process, Commun. Math. Phys. 279, 815844 (2008)]. For the initial state that all particles occupy a single site, the probability distribution of the left-most particle's position at time t is represented by the contour integral of a determinant.

  7. TIME-SERIES PHOTOMETRY OF GLOBULAR CLUSTERS: M62 (NGC 6266), THE MOST RR LYRAE-RICH GLOBULAR CLUSTER IN THE GALAXY?

    SciTech Connect (OSTI)

    Contreras, R.; Catelan, M.; Smith, H. A.; Kuehn, C. A.; Pritzl, B. J.; Borissova, J.

    2010-12-15

    We present new time-series CCD photometry, in the B and V bands, for the moderately metal-rich ([Fe/H] {approx_equal} -1.3) Galactic globular cluster M62 (NGC 6266). The present data set is the largest obtained so far for this cluster and consists of 168 images per filter, obtained with the Warsaw 1.3 m telescope at the Las Campanas Observatory and the 1.3 m telescope of the Cerro Tololo Inter-American Observatory, in two separate runs over the time span of 3 months. The procedure adopted to detect the variable stars was the optimal image subtraction method (ISIS v2.2), as implemented by Alard. The photometry was performed using both ISIS and Stetson's DAOPHOT/ALLFRAME package. We have identified 245 variable stars in the cluster fields that have been analyzed so far, of which 179 are new discoveries. Of these variables, 133 are fundamental mode RR Lyrae stars (RRab), 76 are first overtone (RRc) pulsators, 4 are type II Cepheids, 25 are long-period variables (LPVs), 1 is an eclipsing binary, and 6 are not yet well classified. Such a large number of RR Lyrae stars places M62 among the top two most RR Lyrae-rich (in the sense of total number of RR Lyrae stars present) globular clusters known in the Galaxy, second only to M3 (NGC 5272) with a total of 230 known RR Lyrae stars. Since this study covers most but not all of the cluster area, it is not unlikely that M62 is in fact the most RR Lyrae-rich globular cluster in the Galaxy. In like vein, thanks to the time coverage of our data sets, we were also able to detect the largest sample of LPVs known so far in a Galactic globular cluster. We analyze a variety of Oosterhoff type indicators for the cluster, including mean periods, period distribution, Bailey diagrams, and Fourier decomposition parameters (as well as the physical parameters derived therefrom). All of these indicators clearly show that M62 is an Oosterhoff type I system. This is in good agreement with the moderately high metallicity of the cluster, in spite

  8. Dark Matter Searches with Cherenkov Telescopes: Nearby Dwarf Galaxies or Local Galaxy Clusters?

    SciTech Connect (OSTI)

    Sanchez-Conde, Miguel A.; Cannoni, Mirco; Zandanel, Fabio; Gomez, Mario E.; Prada, Francisco; /IAA, Granada

    2012-06-06

    In this paper, we compare dwarf galaxies and galaxy clusters in order to elucidate which object class is the best target for gamma-ray DM searches with imaging atmospheric Cherenkov telescopes (IACTs). We have built a mixed dwarfs+clusters sample containing some of the most promising nearby dwarf galaxies (Draco, Ursa Minor, Wilman 1 and Segue 1) and local galaxy clusters (Perseus, Coma, Ophiuchus, Virgo, Fornax, NGC 5813 and NGC 5846), and then compute their DM annihilation flux profiles by making use of the latest modeling of their DM density profiles. We also include in our calculations the effect of DM substructure. Willman 1 appears as the best candidate in the sample. However, its mass modeling is still rather uncertain, so probably other candidates with less uncertainties and quite similar fluxes, namely Ursa Minor and Segue 1, might be better options. As for galaxy clusters, Virgo represents the one with the highest flux. However, its large spatial extension can be a serious handicap for IACT observations and posterior data analysis. Yet, other local galaxy cluster candidates with more moderate emission regions, such as Perseus, may represent good alternatives. After comparing dwarfs and clusters, we found that the former exhibit annihilation flux profiles that, at the center, are roughly one order of magnitude higher than those of clusters, although galaxy clusters can yield similar, or even higher, integrated fluxes for the whole object once substructure is taken into account. Even when any of these objects are strictly point-like according to the properties of their annihilation signals, we conclude that dwarf galaxies are best suited for observational strategies based on the search of point-like sources, while galaxy clusters represent best targets for analyses that can deal with rather extended emissions. Finally, we study the detection prospects for present and future IACTs in the framework of the constrained minimal supersymmetric standard model. We

  9. Dimensional scale effects on surface enhanced Raman scattering efficiency of self-assembled silver nanoparticle clusters

    SciTech Connect (OSTI)

    Fasolato, C.; Domenici, F. E-mail: paolo.postorino@roma1.infn.it; De Angelis, L.; Luongo, F.; Postorino, P. E-mail: paolo.postorino@roma1.infn.it; Sennato, S.; Mura, F.; Costantini, F.; Bordi, F.

    2014-08-18

    A study of the Surface Enhanced Raman Scattering (SERS) from micrometric metallic nanoparticle aggregates is presented. The sample is obtained from the self-assembly on glass slides of micro-clusters of silver nanoparticles (60 and 100 nm diameter), functionalized with the organic molecule 4-aminothiophenol in water solution. For nanoparticle clusters at the micron scale, a maximum enhancement factor of 10{sup 9} is estimated from the SERS over the Raman intensity ratio normalized to the single molecule contribution. Atomic force microscopy, correlated to spatially resolved Raman measurements, allows highlighting the connection between morphology and efficiency of the plasmonic system. The correlation between geometric features and SERS response of the metallic structures reveals a linear trend of the cluster maximum scattered intensity as a function of the surface area of the aggregate. On given clusters, the intensity turns out to be also influenced by the number of stacking planes of the aggregate, thus suggesting a plasmonic waveguide effect. The linear dependence results weakened for the largest area clusters, suggesting 30 μm{sup 2} as the upper limit for exploiting the coherence over large scale of the plasmonic response.

  10. GALAXY EVOLUTION IN OVERDENSE ENVIRONMENTS AT HIGH REDSHIFT: PASSIVE EARLY-TYPE GALAXIES IN A CLUSTER AT z {approx} 2

    SciTech Connect (OSTI)

    Strazzullo, V.; Gobat, R.; Daddi, E.; Onodera, M.; Carollo, M.; Dickinson, M.; Renzini, A.; Arimoto, N.; Cimatti, A.; Finoguenov, A.; Chary, R.-R.

    2013-08-01

    We present a study of galaxy populations in the central region of the IRAC-selected, X-ray-detected galaxy cluster Cl J1449+0856 at z = 2. Based on a sample of spectroscopic and photometric cluster members, we investigate stellar populations and the morphological structure of cluster galaxies over an area of {approx}0.7 Mpc{sup 2} around the cluster core. The cluster stands out as a clear overdensity both in redshift space and in the spatial distribution of galaxies close to the center of the extended X-ray emission. The cluster core region (r < 200 kpc) shows a clearly enhanced passive fraction with respect to field levels. However, together with a population of massive, passive galaxies mostly with early-type morphologies, the cluster core also hosts massive, actively star-forming, often highly dust reddened sources. Close to the cluster center, a multi-component system of passive and star-forming galaxies could represent the future brightest cluster galaxy still forming. We observe a clear correlation between passive stellar populations and an early-type morphology, in agreement with field studies at similar redshift. Passive early-type galaxies in this cluster are typically a factor of 2-3 smaller than similarly massive early types at z {approx} 0. On the other hand, these same objects are on average larger by a factor of {approx}2 than field early-types at similar redshift, lending support to recent claims of an accelerated structural evolution in high-redshift dense environments. These results point toward the early formation of a population of massive galaxies, already evolved both in their structure and stellar populations, coexisting with still actively forming massive galaxies in the central regions of young clusters 10 billion years ago.

  11. Modification for complex-particle emission probability in the pre-equilibrium exciton model

    SciTech Connect (OSTI)

    Miao Ron-zhi; Wu Guo-hua; Zheng Wei-han; Liu Jian-ye; Yu Chao-fan; Yu Xie

    1986-04-01

    Starting from a state density formula that distinguishes between neutrons and protons, we have derived corrections for the emission probability W/sub alphabeta/ for complex particles and the purely combinatorial probability R/sub alphabeta/. The calculated results agree well with experimental data and show clear improvement over previous calculations.

  12. Statistics of particle transport in a two-dimensional dusty plasma cluster

    SciTech Connect (OSTI)

    Ratynskaia, S.; Knapek, C.; Rypdal, K.; Khrapak, S.; Morfill, G.

    2005-02-01

    Statistical analysis is performed on long time series of dust particle trajectories in a two-dimensional dusty plasma cluster. Particle transport is found to be superdiffusive on all time scales until the range of particle displacements approaches the size of the cluster. Analysis of probability distribution functions and rescaled range analysis of the position increments show that the signal is non-Gaussian self-similar with Hurst exponent H=0.6, indicating that the superdiffusion is caused by long-range dependencies in the system. Investigation of temporal and spatial characteristics of persistent particle slips demonstrates that they are associated with collective events present on all time scales and responsible for the non-Gaussianity and long-memory effects.

  13. Technical Area 21

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

    Technical Area 21 Technical Area 21 Technical Area 21 was the site of chemical research for refining plutonium and plutonium metal production from 1945 to 1978. August 1, 2013 Technical Area 21 in 2011 Technical Area 21 in 2011 Technical Area 21 (TA-21), also known as DP Site was the site of chemical research for refining plutonium and plutonium metal production from 1945 to 1978. Between 2008 and 2011, MDAs B, U, and V were excavated and removed. 24 buildings were demolished in 2010 and 2011

  14. Visual cluster analysis and pattern recognition methods

    DOE Patents [OSTI]

    Osbourn, Gordon Cecil; Martinez, Rubel Francisco

    2001-01-01

    A method of clustering using a novel template to define a region of influence. Using neighboring approximation methods, computation times can be significantly reduced. The template and method are applicable and improve pattern recognition techniques.

  15. Feature Clustering for Accelerating Parallel Coordinate Descent

    SciTech Connect (OSTI)

    Scherrer, Chad; Tewari, Ambuj; Halappanavar, Mahantesh; Haglin, David J.

    2012-12-06

    We demonstrate an approach for accelerating calculation of the regularization path for L1 sparse logistic regression problems. We show the benefit of feature clustering as a preconditioning step for parallel block-greedy coordinate descent algorithms.

  16. Fermi-LAT constraints on dark matter annihilation cross section from observations of the Fornax cluster

    SciTech Connect (OSTI)

    Ando, Shin'ichiro; Nagai, Daisuke E-mail: daisuke.nagai@yale.edu

    2012-07-01

    We analyze 2.8-yr data of 1–100 GeV photons for clusters of galaxies, collected with the Large Area Telescope onboard the Fermi satellite. By analyzing 49 nearby massive clusters located at high Galactic latitudes, we find no excess gamma-ray emission towards directions of the galaxy clusters. Using flux upper limits, we show that the Fornax cluster provides the most stringent constraints on the dark matter annihilation cross section. Stacking a large sample of nearby clusters does not help improve the limit for most dark matter models. This suggests that a detailed modeling of the Fornax cluster is important for setting robust limits on the dark matter annihilation cross section based on clusters. We therefore perform the detailed mass modeling and predict the expected dark matter annihilation signals from the Fornax cluster, by taking into account effects of dark matter contraction and substructures. By modeling the mass distribution of baryons (stars and gas) around a central bright elliptical galaxy, NGC 1399, and using a modified contraction model motivated by numerical simulations, we show that the dark matter contraction boosts the annihilation signatures by a factor of 4. For dark matter masses around 10 GeV, the upper limit obtained on the annihilation cross section times relative velocity is (σν)∼<(2–3) × 10{sup −25} cm{sup 3} s{sup −1}, which is within a factor of 10 from the value required to explain the dark matter relic density. This effect is more robust than the annihilation boost due to substructure, and it is more important unless the mass of the smallest subhalos is much smaller than that of the Sun.

  17. Accelerating semantic graph databases on commodity clusters

    SciTech Connect (OSTI)

    Morari, Alessandro; Castellana, Vito G.; Haglin, David J.; Feo, John T.; Weaver, Jesse R.; Tumeo, Antonino; Villa, Oreste

    2013-10-06

    We are developing a full software system for accelerating semantic graph databases on commodity cluster that scales to hundreds of nodes while maintaining constant query throughput. Our framework comprises a SPARQL to C++ compiler, a library of parallel graph methods and a custom multithreaded runtime layer, which provides a Partitioned Global Address Space (PGAS) programming model with fork/join parallelism and automatic load balancing over a commodity clusters. We present preliminary results for the compiler and for the runtime.

  18. Electron attenuation in free, neutral ethane clusters

    SciTech Connect (OSTI)

    Winkler, M.; Harnes, J.; Brve, K. J.; Myrseth, V.

    2014-10-28

    The electron effective attenuation length (EAL) in free, neutral ethane clusters has been determined at 40 eV kinetic energy by combining carbon 1s x-ray photoelectron spectroscopy and theoretical lineshape modeling. More specifically, theory is employed to form model spectra on a grid in cluster size (N) and EAL (?), allowing N and ? to be determined by optimizing the goodness-of-fit ?{sup 2}(N, ?) between model and observed spectra. Experimentally, the clusters were produced in an adiabatic-expansion setup using helium as the driving gas, spanning a range of 100600 molecules in mean cluster size. The effective attenuation length was determined to be 8.4??1.9 , in good agreement with an independent estimate of 10 formed on the basis of molecular electron-scattering data and Monte Carlo simulations. The aggregation state of the clusters as well as the cluster temperature and its importance to the derived EAL value are discussed in some depth.

  19. Sputtering of neutral and ionic indium clusters

    SciTech Connect (OSTI)

    Ma, Z.; Coon, S.R.; Calaway, W.F.; Pellin, M.J.; Gruen, D.M.; Von Nagy-Felsobuki, E.I.

    1993-10-01

    Secondary neutral and secondary ion cluster yields were measured during the sputtering of a polycrystalline indium surface by normally incident {approximately}4 keV Ar{sup +} ions. In the secondary neutral mass spectra, indium clusters as large as In{sub 32} were observed. In the secondary ion mass spectra, indium clusters up to In{sub 18}{sup +} were recorded. Cluster yields obtained from both the neutral and ion channel exhibited a power law dependence on the number of constituent atoms, n, in the cluster, with the exponents measured to be {minus}5.6 and {minus}4. 1, respectively. An abundance drop was observed at n=8, 15, and 16 in both the neutral and ion yield distributions suggesting that the stability of the ion (either secondary ion or photoion) plays a significant role in the observed distributions. In addition, our experiments suggest that unimolecular decomposition of the neutral cluster may also plays an important role in the measured yield distributions.

  20. Cosmology and astrophysics with galaxy clusters

    SciTech Connect (OSTI)

    Nagai, Daisuke

    2014-11-20

    Galaxy clusters are the largest gravitationally bound objects in the universe, whose formation is driven by dark energy and dark matter. The majority of the baryonic mass in clusters resides in the hot X-ray emitting plasma, which also leaves imprints in the cosmic microwave background radiation. Recent X-ray and microwave observations have revealed detailed thermodynamic structure of the hot X-ray emitting plasma from their cores to the virial radii, making comparisons of baryonic component in simulations to observations a strong cosmological probe. However, the statistical power of these future surveys can only be exploited for cosmology if and only if we are able to measure the cluster mass with a very high precision. I will discuss recent progress and future challenges for the use of galaxy clusters as precise cosmological probes, with highlights on (1) the importance of understanding thermodynamics and plasma physics in the outskirts of galaxy clusters and (2) prospects for improving the power of cluster-based cosmological measurements using numerical simulations and multi-wavelength observations.

  1. THE STELLAR MASS GROWTH OF BRIGHTEST CLUSTER GALAXIES IN THE IRAC SHALLOW CLUSTER SURVEY

    SciTech Connect (OSTI)

    Lin, Yen-Ting; Brodwin, Mark; Gonzalez, Anthony H.; Bode, Paul; Eisenhardt, Peter R. M.; Stanford, S. A.; Vikhlinin, Alexey

    2013-07-01

    The details of the stellar mass assembly of brightest cluster galaxies (BCGs) remain an unresolved problem in galaxy formation. We have developed a novel approach that allows us to construct a sample of clusters that form an evolutionary sequence, and have applied it to the Spitzer IRAC Shallow Cluster Survey (ISCS) to examine the evolution of BCGs in progenitors of present-day clusters with mass of (2.5-4.5) Multiplication-Sign 10{sup 14} M{sub Sun }. We follow the cluster mass growth history extracted from a high resolution cosmological simulation, and then use an empirical method that infers the cluster mass based on the ranking of cluster luminosity to select high-z clusters of appropriate mass from ISCS to be progenitors of the given set of z = 0 clusters. We find that, between z = 1.5 and 0.5, the BCGs have grown in stellar mass by a factor of 2.3, which is well-matched by the predictions from a state-of-the-art semi-analytic model. Below z = 0.5 we see hints of differences in behavior between the model and observation.

  2. Site Monitoring Area Maps

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

    Maps Individual Permit: Site Monitoring Area Maps Each Site Monitoring Area Map is updated whenever the map information is updated. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email What do these maps show? The Individual Permit for Storm Water site monitoring area maps display the following information: Surface hydrological features Locations of the Site(s) assigned to the Site Monitoring Area (SMA) The Site Monitoring

  3. BRIGHTEST CLUSTER GALAXIES AT THE PRESENT EPOCH

    SciTech Connect (OSTI)

    Lauer, Tod R.; Postman, Marc; Strauss, Michael A.; Graves, Genevieve J.; Chisari, Nora E.

    2014-12-20

    We have obtained photometry and spectroscopy of 433 z ? 0.08 brightest cluster galaxies (BCGs) in a full-sky survey of Abell clusters to construct a BCG sample suitable for probing deviations from the local Hubble flow. The BCG Hubble diagram over 0 < z < 0.08 is consistent to within 2% of the Hubble relation specified by a ? {sub m} = 0.3, ? = 0.7 cosmology. This sample allows us to explore the structural and photometric properties of BCGs at the present epoch, their location in their hosting galaxy clusters, and the effects of the cluster environment on their structure and evolution. We revisit the L{sub m} -? relation for BCGs, which uses ?, the log-slope of the BCG photometric curve of growth, to predict the metric luminosity in an aperture with 14.3kpc radius, L{sub m} , for use as a distance indicator. Residuals in the relation are 0.27mag rms. We measure central stellar velocity dispersions, ?, of the BCGs, finding the Faber-Jackson relation to flatten as the metric aperture grows to include an increasing fraction of the total BCG luminosity. A three-parameter ''metric plane'' relation using ? and ? together gives the best prediction of L{sub m} , with 0.21mag residuals. The distribution of projected spatial offsets, r{sub x} of BCGs from the X-ray-defined cluster center is a steep ? = 2.33 power law over 1 < r{sub x} < 10{sup 3}kpc. The median offset is ?10kpc, but ?15% of the BCGs have r{sub x} > 100kpc. The absolute cluster-dispersion normalized BCG peculiar velocity |?V {sub 1}|/? {sub c} follows an exponential distribution with scale length 0.39 0.03. Both L{sub m} and ? increase with ? {sub c}. The ? parameter is further moderated by both the spatial and velocity offset from the cluster center, with larger ? correlated with the proximity of the BCG to the cluster mean velocity or potential center. At the same time, position in the cluster has little effect on L{sub m} . Likewise, residuals from the metric plane show no correlation with either

  4. Ionized cluster beam technology for material science

    SciTech Connect (OSTI)

    Takagi, Toshinori

    1997-06-20

    The most suitable kinetic energy range of ionized materials in film formation and epitaxial growth is from a few eV to a few hundreds eV, especially, less than about 100eV, when ions are used as a host. The main roles of ions in film formation are the effects due to their kinetic energy and the electronic charge effects which involve the effect to active film formation and the effect acceleration of chemical reactions. Therefore, it is important to develope the technology to transport large volume of a flux of ionized particles with an extremely low incident energy without any troubles due to the space charge effects and charge up problems on the surface. This is the exact motivation for us to have been developing the Ionized Cluster Beam (ICB) technology since 1972. By ICB technology materials (actually wide varieties of materials such as metal, semiconductor, magnetic material, insulator, organic material, etc.) are vaporized and ejected through a small hole nozzle into a high vacuum, where the vaporized material condenses into clusters with loosely coupled atoms with the sizes about from 100 to a few 1000 atoms (mainly 100-2000 atoms) by supercondensation phenomena due to the adiabatic expansion in this evaporation process through a small hole nozzle. In the ICB technology an atom in each cluster is ionized by irradiated by electron shower, and the ionized clusters are accelerated by electric field onto a substrate. The ionized clusters with neutral clusters impinged onto a substrate are spreaded separately into atoms migrating over the substrate, so that the surface migration energy of the impinged atoms, that is, surface diffusion energy are controlled by an incident energy of a cluster. In this report the theoretical and also experimental results of ICB technology are summarized.

  5. Reducing the Probability of Incidents Through Behavior-Based Safety -- An Anomaly or Not?

    SciTech Connect (OSTI)

    Turek, John A

    2002-07-23

    Reducing the probability of incidents through Behavior-Based Safety--an anomaly or not? Can a Behavior-Based Safety (BBS) process reduce the probability of an employee sustaining a work-related injury or illness? This presentation describes the actions taken to implement a sustainable BBS process and evaluates its effectiveness. The BBS process at the Stanford Linear Accelerator Center used a pilot population of national laboratory employees to: Achieve employee and management support; Reduce the probability of employees' sustaining work-related injuries and illnesses; and Provide support for additional funding to expand within the laboratory.

  6. Reducing the Probability of Incidents Through Behavior-Based Safety -- An Anomaly or Not?

    SciTech Connect (OSTI)

    Turek, John A

    2002-07-23

    Reducing the probability of incidents through Behavior-Based Safety-an anomaly or not? Can a Behavior-Based Safety (BBS) process reduce the probability of an employee sustaining a work-related injury or illness? This presentation describes the actions taken to implement a sustainable BBS process and evaluates its effectiveness. The BBS process at the Stanford Linear Accelerator Center used a pilot population of national laboratory employees to: Achieve employee and management support; Reduce the probability of employees' sustaining work-related injuries and illnesses; and Provide support for additional funding to expand within the laboratory.

  7. (Electronic structure and reactivities of transition metal clusters)

    SciTech Connect (OSTI)

    Not Available

    1992-01-01

    The following are reported: theoretical calculations (configuration interaction, relativistic effective core potentials, polyatomics, CASSCF); proposed theoretical studies (clusters of Cu, Ag, Au, Ni, Pt, Pd, Rh, Ir, Os, Ru; transition metal cluster ions; transition metal carbide clusters; bimetallic mixed transition metal clusters); reactivity studies on transition metal clusters (reactivity with H{sub 2}, C{sub 2}H{sub 4}, hydrocarbons; NO and CO chemisorption on surfaces). Computer facilities and codes to be used, are described. 192 refs, 13 figs.

  8. Joint probability safety assessment for NPP defense infrastructure against extreme external natural hazards

    SciTech Connect (OSTI)

    Guilin, L.; Defu, L.; Huajun, L.; Fengqing, W.; Tao, Z.

    2012-07-01

    With the increasing tendency of natural hazards, the typhoon, hurricane and tropical Cyclone induced surge, wave, precipitation, flood and wind as extreme external loads menacing Nuclear Power Plants (NPP) in coastal and inland provinces of China. For all of planned, designed And constructed NPP the National Nuclear Safety Administration of China and IAEA recommended Probable Maximum Hurricane /Typhoon/(PMH/T), Probable Maximum Storm Surge (PMSS), Probable Maximum Flood (PMF), Design Basis Flood (DBF) as safety regulations for NPP defense infrastructures. This paper discusses the joint probability analysis of simultaneous occurrence typhoon induced extreme external hazards and compare with IAEA 2006-2009 recommended safety regulation design criteria for some NPP defense infrastructures along China coast. (authors)

  9. CANDIDATE CLUSTERS OF GALAXIES AT z > 1.3 IDENTIFIED IN THE SPITZER SOUTH POLE TELESCOPE DEEP FIELD SURVEY

    SciTech Connect (OSTI)

    Rettura, A.; Stern, D.; Martinez-Manso, J.; Gettings, D.; Gonzalez, A. H.; Mei, S.; Ashby, M. L. N.; Brodwin, M.; Stanford, S. A.; Bartlett, J. G.

    2014-12-20

    We present 279 galaxy cluster candidates at z > 1.3 selected from the 94 deg{sup 2} Spitzer South Pole Telescope Deep Field (SSDF) survey. We use a simple algorithm to select candidate high-redshift clusters of galaxies based on Spitzer/IRAC mid-infrared data combined with shallow all-sky optical data. We identify distant cluster candidates adopting an overdensity threshold that results in a high purity (80%) cluster sample based on tests in the Spitzer Deep, Wide-Field Survey of the Boötes field. Our simple algorithm detects all three 1.4 < z ≤ 1.75 X-ray detected clusters in the Boötes field. The uniqueness of the SSDF survey resides not just in its area, one of the largest contiguous extragalactic fields observed with Spitzer, but also in its deep, multi-wavelength coverage by the South Pole Telescope (SPT), Herschel/SPIRE, and XMM-Newton. This rich data set will allow direct or stacked measurements of Sunyaev-Zel'dovich effect decrements or X-ray masses for many of the SSDF clusters presented here, and enable a systematic study of the most distant clusters on an unprecedented scale. We measure the angular correlation function of our sample and find that these candidates show strong clustering. Employing the COSMOS/UltraVista photometric catalog in order to infer the redshift distribution of our cluster selection, we find that these clusters have a comoving number density n{sub c}=(0.7{sub −0.6}{sup +6.3})×10{sup −7} h{sup 3} Mpc{sup −3} and a spatial clustering correlation scale length r {sub 0} = (32 ± 7) h {sup –1} Mpc. Assuming our sample is comprised of dark matter halos above a characteristic minimum mass, M {sub min}, we derive that at z = 1.5 these clusters reside in halos larger than M{sub min}=1.5{sub −0.7}{sup +0.9}×10{sup 14} h{sup −1} M{sub ⊙}. We find that the mean mass of our cluster sample is equal to M{sub mean}=1.9{sub −0.8}{sup +1.0}×10{sup 14} h{sup −1} M{sub ⊙}; thus, our sample contains the progenitors of

  10. The 60% Efficient Diesel Engine: Probably, Possible, Or Just a Fantasy? |

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

    Department of Energy The 60% Efficient Diesel Engine: Probably, Possible, Or Just a Fantasy? The 60% Efficient Diesel Engine: Probably, Possible, Or Just a Fantasy? 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005_deer_fairbanks2.pdf (1.21 MB) More Documents & Publications DOE's Launch of High-Efficiency Thermiekectrics Projects Thermoelectric Developments for Vehicular Applications Solid-State Energy Conversion Overview

  11. Inner Area Principles

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

    Inner Area Principles The Inner Area principles proposed by the Tri-Parties are a good beginning toward consideration of what kind of approach will be needed to remedy the problems of the Central Plateau. However, the Board feels that some principles have been overlooked in the preparation of these. [1] While it has been generally agreed that designated waste disposal facilities of the Inner Area (like ERDF and IDF) would not be candidates for remediation. What happened to the remedial approach

  12. Imperial Valley Geothermal Area

    Broader source: Energy.gov [DOE]

    The Imperial Valley Geothermal project consists of 10 generating plants in the Salton Sea Known Geothermal Resource Area in Southern California's Imperial Valley. The combined capacity at Imperial...

  13. Western Area Power Administration

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

    Area Power Administration Follow-up to Nov. 25, 2008 Transition ... Southwestern Power Administration CONSTRUCTION BUDGET ITEM DESCRIPTION FY 2009* MICROWAVE ...

  14. Supersonic Bare Metal Cluster Beams. Final Report

    DOE R&D Accomplishments [OSTI]

    Smalley, R. E.

    1997-10-14

    A major portion of the project involved elucidating the relation between reactivity and the electronic structure of transition-metal (TM) clusters of 2--200 atoms, which required the construction and continuous development of two principal apparati; the Fourier Transform-Ion Cyclotron Resonance (FT-ICR) apparatus, and Ultraviolet Photoelectron Spectroscopy (UPS). Together, these machines have enabled the most detailed probing of the structure and chemical reactivity of TM clusters. Clusters of all the transition metals were included in these studies. Fundamental aspects in chemisorption, reactivity, and heterogeneous catalysis have also become better understood as a result of these experiments for important classes of systems such as H{sub 2}, CO, and CO{sub 2} adsorbed onto clusters of many of the metals listed above. In particular, a correlation was found between reactivity of H{sub 2} with Fe, Co, and Ni clusters and differences between the cluster IP and EA. As recounted in a previous technical report, the DOE`s role in the initial discovery of fullerenes at Rice was central, and from the start investigations were made into metal atoms trapped in the fullerenes cage. More recently, the authors have discovered that 2--4 atoms of La, Y, or Sc can be produced by laser vaporization of composite graphite/metal-oxide disks. This work was largely motivated by the prospects of using such endohedral TM metals for their catalytic activity without the well-known difficulties of effective support media and lack of control over particle size. Thus, while it will certainly be important to discover ways to efficiently scale up production (e.g., the solar generation method explored with DOE support), the efforts have concentrated more on characterization, purification, and manipulation of doped fullerenes. For the past two years, much of the group`s effort has involved the production, purification, and characterization of carbon nanotubes.

  15. Completion report for Well Cluster ER-20-6

    SciTech Connect (OSTI)

    1998-02-01

    The Well Cluster ER-20-6 drilling and completion project was conducted during February, March, and April of 1996 in support of the Nevada Environmental Restoration Project at the Nevada Test Site (NTS), Nye County, Nevada. This project is part of the DOE`s Underground Test Area (UGTA) subproject at the NTS. The primary UGTA tasks include collecting geological, geophysical, and hydrological data from new and existing wells to define groundwater quality as well as pathways and rates of groundwater migration at the NTS. A program of drilling wells near the sites of selected underground nuclear tests (near-field drilling) was implemented as part of the UGTA subproject to obtain site-specific data on the nature and extent of migration of radionuclides produced by an underground nuclear explosion. The ER-20-6 near-field drilling project was originally planned to be very similar to that recently conducted at Well Cluster ER-20-5, which was designed to obtain data on the existing hydrologic regime near the site of an underground nuclear explosion (IT, 1995; IT, 1996a). However, after further consideration of the goals of the near-field drilling program and the characteristics of the BULLION site, the TWG recommended that the ER-20-6 project be redesigned to accommodate a forced-gradient experiment. This proposed experiment is expected to yield more realistic estimates of transport parameters than can be deduced from sampling and testing natural groundwater flow systems.

  16. CLUSTERING OF ?-RAY-SELECTED 2LAC FERMI BLAZARS

    SciTech Connect (OSTI)

    Allevato, V.; Finoguenov, A.; Cappelluti, N.

    2014-12-20

    We present the first measurement of the projected correlation function of 485 ?-ray-selected blazars, divided into 175 BL Lacertae (BL Lacs) and 310 flat-spectrum radio quasars (FSRQs) detected in the 2 year all-sky survey by the Fermi-Large Area Telescope. We find that Fermi BL Lacs and FSRQs reside in massive dark matter halos (DMHs) with log M{sub h} = 13.35{sub ?0.14}{sup +0.20} and log M{sub h} = 13.40{sub ?0.19}{sup +0.15} h {sup 1} M {sub ?}, respectively, at low (z ? 0.4) and high (z ? 1.2) redshift. In terms of clustering properties, these results suggest that BL Lacs and FSRQs are similar objects residing in the same dense environment typical of galaxy groups, despite their different spectral energy distributions, power, and accretion rates. We find no difference in the typical bias and hosting halo mass between Fermi blazars and radio-loud active galactic nuclei (AGNs), supporting the unification scheme simply equating radio-loud objects with misaligned blazar counterparts. This similarity in terms of the typical environment they preferentially live in, suggests that blazars tend to occupy the center of DMHs, as already pointed out for radio-loud AGNs. This implies, in light of several projects looking for the ?-ray emission from DM annihilation in galaxy clusters, a strong contamination from blazars to the expected signal from DM annihilation.

  17. The sluggs survey: HST/ACS mosaic imaging of the NGC 3115 globular cluster system

    SciTech Connect (OSTI)

    Jennings, Zachary G.; Romanowsky, Aaron J.; Brodie, Jean P.; Arnold, Jacob A.; Strader, Jay; Lin, Dacheng; Irwin, Jimmy A.; Wong, Ka-Wah; Sivakoff, Gregory R.

    2014-08-01

    We present Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) g and z photometry and half-light radii R {sub h} measurements of 360 globular cluster (GC) candidates around the nearby S0 galaxy NGC 3115. We also include Subaru/Suprime-Cam g, r, and i photometry of 421 additional candidates. The well-established color bimodality of the GC system is obvious in the HST/ACS photometry. We find evidence for a 'blue tilt' in the blue GC subpopulation, wherein the GCs in the blue subpopulation get redder as luminosity increases, indicative of a mass-metallicity relationship. We find a color gradient in both the red and blue subpopulations, with each group of clusters becoming bluer at larger distances from NGC 3115. The gradient is of similar strength in both subpopulations, but is monotonic and more significant for the blue clusters. On average, the blue clusters have ?10% larger R {sub h} than the red clusters. This average difference is less than is typically observed for early-type galaxies but does match that measured in the literature for the Sombrero Galaxy (M104), suggesting that morphology and inclination may affect the measured size difference between the red and blue clusters. However, the scatter on the R {sub h} measurements is large. We also identify 31 clusters more extended than typical GCs, which we term ultra-compact dwarf (UCD) candidates. Many of these objects are actually considerably fainter than typical UCDs. While it is likely that a significant number will be background contaminants, six of these UCD candidates are spectroscopically confirmed as NGC 3115 members. To explore the prevalence of low-mass X-ray binaries in the GC system, we match our ACS and Suprime-Cam detections to corresponding Chandra X-ray sources. We identify 45 X-ray-GC matches: 16 among the blue subpopulation and 29 among the red subpopulation. These X-ray/GC coincidence fractions are larger than is typical for most GC systems, probably due to the increased depth of

  18. A Cluster-based Method to Map Urban Area from DMSP/OLS Nightlights...

    Office of Scientific and Technical Information (OSTI)

    Two large countries of United States and China with different urbanization patterns were ... at the state level, and less than 1% in China, ranging from lower than 0.1% to about 5% ...

  19. Peeking Network States with Clustered Patterns

    SciTech Connect (OSTI)

    Kim, Jinoh; Sim, Alex

    2015-10-20

    Network traffic monitoring has long been a core element for effec- tive network management and security. However, it is still a chal- lenging task with a high degree of complexity for comprehensive analysis when considering multiple variables and ever-increasing traffic volumes to monitor. For example, one of the widely con- sidered approaches is to scrutinize probabilistic distributions, but it poses a scalability concern and multivariate analysis is not gen- erally supported due to the exponential increase of the complexity. In this work, we propose a novel method for network traffic moni- toring based on clustering, one of the powerful deep-learning tech- niques. We show that the new approach enables us to recognize clustered results as patterns representing the network states, which can then be utilized to evaluate “similarity” of network states over time. In addition, we define a new quantitative measure for the similarity between two compared network states observed in dif- ferent time windows, as a supportive means for intuitive analysis. Finally, we demonstrate the clustering-based network monitoring with public traffic traces, and show that the proposed approach us- ing the clustering method has a great opportunity for feasible, cost- effective network monitoring.

  20. Geothermal br Resource br Area Geothermal br Resource br Area...

    Open Energy Info (EERE)

    Aluto Langano Geothermal Area Aluto Langano Geothermal Area East African Rift System Ethiopian Rift Valley Major Normal Fault Basalt MW K Amatitlan Geothermal Area Amatitlan...

  1. Transition properties from the Hermitian formulation of the coupled cluster polarization propagator

    SciTech Connect (OSTI)

    Tucholska, Aleksandra M. Modrzejewski, Marcin; Moszynski, Robert

    2014-09-28

    Theory of one-electron transition density matrices has been formulated within the time-independent coupled cluster method for the polarization propagator [R. Moszynski, P. S. ?uchowski, and B. Jeziorski, Coll. Czech. Chem. Commun. 70, 1109 (2005)]. Working expressions have been obtained and implemented with the coupled cluster method limited to single, double, and linear triple excitations (CC3). Selected dipole and quadrupole transition probabilities of the alkali earth atoms, computed with the new transition density matrices are compared to the experimental data. Good agreement between theory and experiment is found. The results obtained with the new approach are of the same quality as the results obtained with the linear response coupled cluster theory. The one-electron density matrices for the ground state in the CC3 approximation have also been implemented. The dipole moments for a few representative diatomic molecules have been computed with several variants of the new approach, and the results are discussed to choose the approximation with the best balance between the accuracy and computational efficiency.

  2. INFRARED VIBRATIONAL PREDISSOCIATION SPECTROSCOPY OF WATER CLUSTERS BY THE CROSSED LASER MOLECULAR BEAM TECHNIQUE

    SciTech Connect (OSTI)

    Vernon, M.F.; Krajnovich, D.J.; Kwok, H.S.; Lisy, J.M.; Shen, Y.R.; Lee, Y.T.

    1981-11-01

    Water clusters formed in a molecular beam are predissociated by tunable, pulsed, infrared radiation in the frequency range 2900~3750 cm{sup -1}. The recoiling fragments are detected off axis from the molecular beam using a rotatable mass spectrometer. Arguments are presented which show that the measured frequency dependent signal at a fixed detector angle is proportional to the absorption spectrum of the clusters. It is found that the spectra of clusters containing three or more water molecules are remarkably similar to the liquid phase spectrum. Dynamical information on the predissociation process is obtained from the velocity distribution of the fragments. An upper limit to the excited vibrational state lifetime of ~1 microsecond is observed for the results reported here. The most probable dissociation process concentrates the available excess energy into the internal motions of the fragment molecules. Both the time scale and translational energy distribution are consistent with the qualitative predictions of current theoretical models for cluster predissociation. From adiabatic dissociation trajectories and Monte Carlo simulations it is seen that the strong coupling present in the water polymers probably invalidates the simpler "diatomic" picture formulations of cluster predissociation. Instead, the energy can be extensively shared among the intermolecular motions in the polymer before dissociation. Comparison between current intermolecular potentials describing liquid water and the observed frequencies is made in the normal mode approximation. The inability of any potential to predict the gross spectral features (the number of bands and their observed frequency shift from the gas phase monomer) suggests that substantial improvement in the potential energy functions are possible, but that more accurate methods of solving the vibrational wave equation are necessary before a proper explanation of the spectral fine structure is possible. The observed differences

  3. Testing chameleon gravity with the Coma cluster

    SciTech Connect (OSTI)

    Terukina, Ayumu; Yamamoto, Kazuhiro; Lombriser, Lucas; Bacon, David; Koyama, Kazuya; Nichol, Robert C. E-mail: lucas.lombriser@port.ac.uk E-mail: david.bacon@port.ac.uk E-mail: bob.nichol@port.ac.uk

    2014-04-01

    We propose a novel method to test the gravitational interactions in the outskirts of galaxy clusters. When gravity is modified, this is typically accompanied by the introduction of an additional scalar degree of freedom, which mediates an attractive fifth force. The presence of an extra gravitational coupling, however, is tightly constrained by local measurements. In chameleon modifications of gravity, local tests can be evaded by employing a screening mechanism that suppresses the fifth force in dense environments. While the chameleon field may be screened in the interior of the cluster, its outer region can still be affected by the extra force, introducing a deviation between the hydrostatic and lensing mass of the cluster. Thus, the chameleon modification can be tested by combining the gas and lensing measurements of the cluster. We demonstrate the operability of our method with the Coma cluster, for which both a lensing measurement and gas observations from the X-ray surface brightness, the X-ray temperature, and the Sunyaev-Zel'dovich effect are available. Using the joint observational data set, we perform a Markov chain Monte Carlo analysis of the parameter space describing the different profiles in both the Newtonian and chameleon scenarios. We report competitive constraints on the chameleon field amplitude and its coupling strength to matter. In the case of f(R) gravity, corresponding to a specific choice of the coupling, we find an upper bound on the background field amplitude of |f{sub R0}| < 6 10{sup ?5}, which is currently the tightest constraint on cosmological scales.

  4. THERMODYNAMICS OF THE COMA CLUSTER OUTSKIRTS

    SciTech Connect (OSTI)

    Simionescu, A.; Werner, N.; Urban, O.; Allen, S. W.; Fabian, A. C.; Sanders, J. S.; Walker, S. A.; Mantz, A.; Matsushita, K.; Sasaki, T.; Sato, T.; Nulsen, P. E. J.; Takei, Y.

    2013-09-20

    We present results from a large mosaic of Suzaku observations of the Coma Cluster, the nearest and X-ray brightest hot ({approx}8 keV), dynamically active, non-cool core system, focusing on the thermodynamic properties of the intracluster medium on large scales. For azimuths not aligned with an infalling subcluster toward the southwest, our measured temperature and X-ray brightness profiles exhibit broadly consistent radial trends, with the temperature decreasing from about 8.5 keV at the cluster center to about 2 keV at a radius of 2 Mpc, which is the edge of our detection limit. The southwest merger significantly boosts the surface brightness, allowing us to detect X-ray emission out to {approx}2.2 Mpc along this direction. Apart from the southwestern infalling subcluster, the surface brightness profiles show multiple edges around radii of 30-40 arcmin. The azimuthally averaged temperature profile, as well as the deprojected density and pressure profiles, all show a sharp drop consistent with an outwardly-propagating shock front located at 40 arcmin, corresponding to the outermost edge of the giant radio halo observed at 352 MHz with the Westerbork Synthesis Radio Telescope. The shock front may be powering this radio emission. A clear entropy excess inside of r{sub 500} reflects the violent merging events linked with these morphological features. Beyond r{sub 500}, the entropy profiles of the Coma Cluster along the relatively relaxed directions are consistent with the power-law behavior expected from simple models of gravitational large-scale structure formation. The pressure is also in agreement at these radii with the expected values measured from Sunyaev-Zel'dovich data from the Planck satellite. However, due to the large uncertainties associated with the Coma Cluster measurements, we cannot yet exclude an entropy flattening in this system consistent with that seen in more relaxed cool core clusters.

  5. Decontamination & decommissioning focus area

    SciTech Connect (OSTI)

    1996-08-01

    In January 1994, the US Department of Energy Office of Environmental Management (DOE EM) formally introduced its new approach to managing DOE`s environmental research and technology development activities. The goal of the new approach is to conduct research and development in critical areas of interest to DOE, utilizing the best talent in the Department and in the national science community. To facilitate this solutions-oriented approach, the Office of Science and Technology (EM-50, formerly the Office of Technology Development) formed five Focus AReas to stimulate the required basic research, development, and demonstration efforts to seek new, innovative cleanup methods. In February 1995, EM-50 selected the DOE Morgantown Energy Technology Center (METC) to lead implementation of one of these Focus Areas: the Decontamination and Decommissioning (D & D) Focus Area.

  6. Hanford 300 Area ROD

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

    300 Area ROD Briefing to the Hanford Advisory Board March 6, 2014 Larry Gadbois -- EPA Recap of the 300 Area ROD Primary new concept -- Uranium Sequestration: * Purpose: Accelerate restoration of groundwater uranium contamination. * Protect groundwater from downward leaching from the vadose zone (overlying soil). * Add phosphate to chemically bond with uranium into geologically stable autunite. Does not dissolve. * Dissolve phosphate in water, apply at ground surface, inject into the ground,

  7. Physics Thrust Areas

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

    Thrust Areas Physics Thrust Areas Physics Division serves the nation through its broad portfolio of fundamental and applied research. Quality basic science research: critical component of maintaining our capabilities in national security research To further understand the physical world, generate new or improved technology in experimental physics, and establish a physics foundation for current and future Los Alamos programs, Physics Division leverages its expertise and experimental capabilities

  8. Reconstruction of ionization probabilities from spatially averaged data in N dimensions

    SciTech Connect (OSTI)

    Strohaber, J.; Kolomenskii, A. A.; Schuessler, H. A.

    2010-07-15

    We present an analytical inversion technique, which can be used to recover ionization probabilities from spatially averaged data in an N-dimensional detection scheme. The solution is given as a power series in intensity. For this reason, we call this technique a multiphoton expansion (MPE). The MPE formalism was verified with an exactly solvable inversion problem in two dimensions, and probabilities in the postsaturation region, where the intensity-selective scanning approach breaks down, were recovered. In three dimensions, ionization probabilities of Xe were successfully recovered with MPE from simulated (using the Ammosov-Delone-Krainov tunneling theory) ion yields. Finally, we tested our approach with intensity-resolved benzene-ion yields, which show a resonant multiphoton ionization process. By applying MPE to this data (which were artificially averaged), the resonant structure was recovered, which suggests that the resonance in benzene may have been observed in spatially averaged data taken elsewhere.

  9. Field Observation GoAmazon Neutral cluster Air Ion Spectrometer...

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

    of the Green Ocean Amazon: Neutral Cluster Air Ion Spectrometer (NAIS) Final Campaign ... DOESC-ARM-15-060 Field Observation of the Green Ocean Amazon: Neutral Cluster Air Ion ...

  10. Spatial clustering of pixels of a multispectral image

    DOE Patents [OSTI]

    Conger, James Lynn

    2014-08-19

    A method and system for clustering the pixels of a multispectral image is provided. A clustering system computes a maximum spectral similarity score for each pixel that indicates the similarity between that pixel and the most similar neighboring. To determine the maximum similarity score for a pixel, the clustering system generates a similarity score between that pixel and each of its neighboring pixels and then selects the similarity score that represents the highest similarity as the maximum similarity score. The clustering system may apply a filtering criterion based on the maximum similarity score so that pixels with similarity scores below a minimum threshold are not clustered. The clustering system changes the current pixel values of the pixels in a cluster based on an averaging of the original pixel values of the pixels in the cluster.

  11. OpenCL now Available on Dirac GPU Cluster

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

    OpenCL now Available on Dirac GPU Cluster OpenCL now Available on Dirac GPU Cluster October 30, 2013 by Francesca Verdier As requested by many Dirac users, NERSC is migrating Dirac...

  12. Dirac GPU Cluster to be Retired December 12

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

    Dirac GPU Cluster to be Retired December 12 Dirac GPU Cluster to be Retired December 12 November 12, 2014 by Francesca Verdier As previously announced, the Dirac GPU testbed will...

  13. Electric quadrupole transition probabilities and line strengths of Ti{sup 11+}

    SciTech Connect (OSTI)

    Gke, Yasin; elik, Gltekin; Y?ld?z, Murat

    2014-07-15

    Electric quadrupole transition probabilities and line strengths have been calculated using the weakest bound electron potential model for sodium-like titanium, considering many transition arrays. We employed numerical Coulomb approximation and non-relativistic HartreeFock wavefunctions for the expectation values of radii in determination of parameters of the model. The necessary energy values have been taken from experimental data in the literature. The calculated electric quadrupole line strengths have been compared with available data in the literature and good agreement has been obtained. Moreover, some electric quadrupole transition probability and line strength values not existing in the literature for some highly excited levels have been obtained using this method.

  14. The 2013 Clusters, Nanocrystals & Nanostructures Gordon Research Conference/Gordon Research Seminar

    SciTech Connect (OSTI)

    Krauss, Todd D.

    2014-11-25

    The fundamental properties of small particles and their potential for groundbreaking applications are among the most exciting areas of study in modern physics, chemistry, and materials science. The Clusters, Nanocrystals & Nanostructures Gordon ResearchConference and Gordon Research Seminar synthesize contributions from these inter-related fields that reflect the pivotal role of nano-particles at the interface between these disciplines. Size-dependent optical, electronic, magnetic and catalytic properties offer prospects for applications in many fields, and possible solutions for many of the grand challenges facing energy generation, consumption, delivery, and storage in the 21st century. The goal of the 2013 Clusters, Nanocrystals & Nanostructures Gordon Research Conference and Gordon Research Seminar is to continue the historical interdisciplinary tradition of this series and discuss the most recent advances, basic scientific questions, and emerging applications of clusters, nanocrystals, and nanostructures. The Clusters, Nanocrystals & Nanostructures GRC/GRS traditionally brings together the leading scientific groups that have made significant recent advances in one or more fundamental nanoscience or nanotechnology areas. Broad interests of the DOE BES and Solar Photochemistry Program addressed by this meeting include the areas of solar energy to fuels conversion, new photovoltaic systems, fundamental characterization of nanomaterials, magnetism, catalysis, and quantum physics. The vast majority of speakers and attendees will address either directly the topic of nanotechnology for photoinduced charge transfer, charge transport, and catalysis, or will have made significant contributions to related areas that will impact these fields indirectly. These topics have direct relevance to the mission of the DOE BES since it is this cutting-edge basic science that underpins our energy future.

  15. NREL: Process Development and Integration Laboratory - Silicon Cluster Tool

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

    Capabilities Silicon Cluster Tool Capabilities Photo of a cylindrical metal chamber surrounded by numerous other smaller cylindrical or rectangular chambers. Each tool has several flanges and is typically held within a metal frame or rack. A computer is on a table in front of a cabinet of electronic equipment. Silicon cluster tool in the Process Development and Integration Laboratory. The Silicon cluster tool within the Process Development and Integration Laboratory is a 10-port cluster tool

  16. Topological one-way quantum computation on verified logical cluster...

    Office of Scientific and Technical Information (OSTI)

    NOISE; QUANTUM COMPUTERS; QUBITS; STAR CLUSTERS; THREE-DIMENSIONAL CALCULATIONS; TOPOLOGY; VERIFICATION COMPUTERS; INFORMATION; MATHEMATICS; QUANTUM INFORMATION Word Cloud ...

  17. Computer System, Cluster, and Networking Summer Institute Program Description

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

    System, Cluster, and Networking Summer Institute Program Description The Computer System, Cluster, and Networking Summer Institute (CSCNSI) is a focused technical enrichment program targeting third-year college undergraduate students currently engaged in a computer science, computer engineering, or similar major. The program emphasizes practical skill development in setting up, configuring, administering, testing, monitoring, and scheduling computer systems, supercomputer clusters, and computer

  18. Probing the z > 6 universe with the first Hubble frontier fields cluster A2744

    SciTech Connect (OSTI)

    Atek, Hakim; Kneib, Jean-Paul; Richard, Johan; Clement, Benjamin; Egami, Eiichi; Ebeling, Harald; Jauzac, Mathilde; Jullo, Eric; Limousin, Marceau; Laporte, Nicolas; Natarajan, Priyamvada

    2014-05-01

    The Hubble Frontier Fields program combines the capabilities of the Hubble Space Telescope (HST) with the gravitational lensing of massive galaxy clusters to probe the distant universe to an unprecedented depth. Here, we present the results of the first combined HST and Spitzer observations of the cluster A-2744. We combine the full near-infrared data with ancillary optical images to search for gravitationally lensed high-redshift (z ? 6) galaxies. We report the detection of 15 I {sub 814} dropout candidates at z ? 6-7 and one Y {sub 105} dropout at z ? 8 in a total survey area of 1.43 arcmin{sup 2} in the source plane. The predictions of our lens model also allow us to identify five multiply imaged systems lying at redshifts between z ? 6 and z ? 8. Thanks to constraints from the mass distribution in the cluster, we were able to estimate the effective survey volume corrected for completeness and magnification effects. This was in turn used to estimate the rest-frame ultraviolet luminosity function (LF) at z ? 6-8. Our LF results are generally in agreement with the most recent blank field estimates, confirming the feasibility of surveys through lensing clusters. Although based on a shallower observations than what will be achieved in the final data set including the full Advanced Camera for Survey observations, the LF presented here goes down to M {sub UV} ?18.5, corresponding to 0.2L {sup *} at z ? 7 with one identified object at M {sub UV} ?15 thanks to the highly magnified survey areas. This early study forecasts the power of using massive galaxy clusters as cosmic telescopes and its complementarity to blank fields.

  19. Effects of quadrupole vibration of the fragments on. mu. - final state probabilities

    SciTech Connect (OSTI)

    Zheng Guo-tong; Wang Yan-sen; Yuan Zu-shu; Qiu Zhi-hong

    1988-01-01

    The muon final-state probabilities after muon-induced fission of /sup 238/U are calculated by using the LCAO (Linear Combination of Atomic Orbital) method. The ordinary viscosity of the fissioning nucleus, the deformations and quadrupole vibrations of the two fragments are taken into account. The calculated results are compared with those obtained by neglecting the quadrupole vibration

  20. OLED area illumination source

    DOE Patents [OSTI]

    Foust, Donald Franklin; Duggal, Anil Raj; Shiang, Joseph John; Nealon, William Francis; Bortscheller, Jacob Charles

    2008-03-25

    The present invention relates to an area illumination light source comprising a plurality of individual OLED panels. The individual OLED panels are configured in a physically modular fashion. Each OLED panel comprising a plurality of OLED devices. Each OLED panel comprises a first electrode and a second electrode such that the power being supplied to each individual OLED panel may be varied independently. A power supply unit capable of delivering varying levels of voltage simultaneously to the first and second electrodes of each of the individual OLED panels is also provided. The area illumination light source also comprises a mount within which the OLED panels are arrayed.

  1. Operational Area Monitoring Plan

    Office of Legacy Management (LM)

    ' SECTION 11.7B Operational Area Monitoring Plan for the Long -Term H yd rol og ical M o n i to ri ng - Program Off The Nevada Test Site S . C. Black Reynolds Electrical & Engineering, Co. and W. G. Phillips, G. G. Martin, D. J. Chaloud, C. A. Fontana, and 0. G. Easterly Environmental Monitoring Systems Laboratory U. S. Environmental Protection Agency October 23, 1991 FOREWORD This is one of a series of Operational Area Monitoring Plans that comprise the overall Environmental Monitoring Plan

  2. SIMILARITIES IN POPULATIONS OF STAR CLUSTERS

    SciTech Connect (OSTI)

    Fall, S. Michael; Chandar, Rupali E-mail: rupali.chandar@utoledo.edu

    2012-06-20

    We compare the observed mass functions and age distributions of star clusters in six well-studied galaxies: the Milky Way, Magellanic Clouds, M83, M51, and Antennae. In combination, these distributions span wide ranges of mass and age: 10{sup 2} {approx}< M/M{sub Sun} {approx}< 10{sup 6} and 10{sup 6} {approx}< {tau}/yr {approx}< 10{sup 9}. We confirm that the distributions are well represented by power laws: dN/dM{proportional_to}M{sup {beta}} with {beta} Almost-Equal-To -1.9 and dN/d{tau}{proportional_to}{tau}{sup {gamma}} with {gamma} Almost-Equal-To -0.8. The mass and age distributions are approximately independent of each other, ruling out simple models of mass-dependent disruption. As expected, there are minor differences among the exponents at a level close to the true uncertainties, {epsilon}{sub {beta}} {approx} {epsilon}{sub {gamma}} {approx} 0.1-0.2. However, the overwhelming impression is the similarity of the mass functions and age distributions of clusters in these different galaxies, including giant and dwarf, quiescent and interacting galaxies. This is an important empirical result, justifying terms such as 'universal' or 'quasi-universal'. We provide a partial theoretical explanation for these observations in terms of physical processes operating during the formation and disruption of the clusters, including star formation and feedback, subsequent stellar mass loss, and tidal interactions with passing molecular clouds. A full explanation will require additional information about the molecular clumps and star clusters in galaxies beyond the Milky Way.

  3. Visualization Clusters | Argonne Leadership Computing Facility

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

    Analytics and Visualization Visualization Cluster Cooley The primary purpose of Cooley is to analyze and visualize data produced on Mira. Equipped with state-of-the-art graphics processing units (GPUs), Cooley converts computational data from Mira into high-resolution visual representations. The resulting images, videos, and animations help users to better analyze and understand the data generated by Mira. Cooley can also be used for statistical analysis, helping to pinpoint trends in the

  4. Star-cluster mass and age distributions of two fields in M83 based on HST/WFC3 observations

    SciTech Connect (OSTI)

    Chandar, Rupali; Whitmore, Bradley C.; Calzetti, Daniela; O'Connell, Robert

    2014-05-20

    We study star clusters in two fields in the nearby spiral galaxy M83 using broadband and narrowband optical imaging taken with the Wide Field Camera 3 onboard the Hubble Space Telescope. We present results on the basis of several different catalogs of star clusters in inner and outer fields, and we conclude that different methods of selection do not strongly affect the results, particularly for clusters older than ?10 Myr. The age distributions can be described by a power law, dN/d???{sup ?}, with ? ? 0.84 0.12 in the inner field, and ? ? 0.48 0.12 in the outer field for ? ? 10 Myr. We bracket the difference, ??, between the two fields to be in the 0.18 to 0.36 range, based on estimates of the relative star-formation histories. The mass functions can also be described by a power law, dN/dM?M {sup ?}, with ? ? 1.98 0.14 and ? ? 2.34 0.26 in the inner and outer fields, respectively. We conclude that the shapes of the mass and age distributions of the clusters in the two fields are similar, as predicted by the quasi-universal model. Any differences between the two fields are at the ?2?-3? (?1?-2?) level for the age (mass) distributions. Therefore, any dependence of these distributions on the local environment is probably weak. We compare the shapes of the distributions with those predicted by two popular cluster disruption models. We find that both show evidence that the clusters are disrupted at a rate that is approximately independent of their mass. We compare the shapes of the distributions with those predicted by two popular cluster disruption models, and find that both show evidence that the clusters are disrupted at a rate that is approximately independent of their mass, and that observational results do not support the earlier disruption of lower-mass clusters relative to their higher-mass counterparts.

  5. Some Results on the Analysis of Stochastic Processes with Uncertain Transition Probabilities and Robust Optimal Control

    SciTech Connect (OSTI)

    Keyong Li; Seong-Cheol Kang; I. Ch. Paschalidis

    2007-09-01

    This paper investigates stochastic processes that are modeled by a finite number of states but whose transition probabilities are uncertain and possibly time-varying. The treatment of uncertain transition probabilities is important because there appears to be a disconnection between the practice and theory of stochastic processes due to the difficulty of assigning exact probabilities to real-world events. Also, when the finite-state process comes as a reduced model of one that is more complicated in nature (possibly in a continuous state space), existing results do not facilitate rigorous analysis. Two approaches are introduced here. The first focuses on processes with one terminal state and the properties that affect their convergence rates. When a process is on a complicated graph, the bound of the convergence rate is not trivially related to that of the probabilities of individual transitions. Discovering the connection between the two led us to define two concepts which we call 'progressivity' and 'sortedness', and to a new comparison theorem for stochastic processes. An optimality criterion for robust optimal control also derives from this comparison theorem. In addition, this result is applied to the case of mission-oriented autonomous robot control to produce performance estimate within a control framework that we propose. The second approach is in the MDP frame work. We will introduce our preliminary work on optimistic robust optimization, which aims at finding solutions that guarantee the upper bounds of the accumulative discounted cost with prescribed probabilities. The motivation here is to address the issue that the standard robust optimal solution tends to be overly conservative.

  6. Coscheduling Technique for Symmetric Multiprocessor Clusters

    SciTech Connect (OSTI)

    Yoo, A B; Jette, M A

    2000-09-18

    Coscheduling is essential for obtaining good performance in a time-shared symmetric multiprocessor (SMP) cluster environment. However, the most common technique, gang scheduling, has limitations such as poor scalability and vulnerability to faults mainly due to explicit synchronization between its components. A decentralized approach called dynamic coscheduling (DCS) has been shown to be effective for network of workstations (NOW), but this technique is not suitable for the workloads on a very large SMP-cluster with thousands of processors. Furthermore, its implementation can be prohibitively expensive for such a large-scale machine. IN this paper, they propose a novel coscheduling technique based on the DCS approach which can achieve coscheduling on very large SMP-clusters in a scalable, efficient, and cost-effective way. In the proposed technique, each local scheduler achieves coscheduling based upon message traffic between the components of parallel jobs. Message trapping is carried out at the user-level, eliminating the need for unsupported hardware or device-level programming. A sending process attaches its status to outgoing messages so local schedulers on remote nodes can make more intelligent scheduling decisions. Once scheduled, processes are guaranteed some minimum period of time to execute. This provides an opportunity to synchronize the parallel job's components across all nodes and achieve good program performance. The results from a performance study reveal that the proposed technique is a promising approach that can reduce response time significantly over uncoordinated time-sharing and batch scheduling.

  7. MEASURING THE MASS DISTRIBUTION IN GALAXY CLUSTERS

    SciTech Connect (OSTI)

    Geller, Margaret J.; Diaferio, Antonaldo; Rines, Kenneth J.; Serra, Ana Laura E-mail: diaferio@ph.unito.it E-mail: serra@to.infn.it

    2013-02-10

    Cluster mass profiles are tests of models of structure formation. Only two current observational methods of determining the mass profile, gravitational lensing, and the caustic technique are independent of the assumption of dynamical equilibrium. Both techniques enable the determination of the extended mass profile at radii beyond the virial radius. For 19 clusters, we compare the mass profile based on the caustic technique with weak lensing measurements taken from the literature. This comparison offers a test of systematic issues in both techniques. Around the virial radius, the two methods of mass estimation agree to within {approx}30%, consistent with the expected errors in the individual techniques. At small radii, the caustic technique overestimates the mass as expected from numerical simulations. The ratio between the lensing profile and the caustic mass profile at these radii suggests that the weak lensing profiles are a good representation of the true mass profile. At radii larger than the virial radius, the extrapolated Navarro, Frenk and White fit to the lensing mass profile exceeds the caustic mass profile. Contamination of the lensing profile by unrelated structures within the lensing kernel may be an issue in some cases; we highlight the clusters MS0906+11 and A750, superposed along the line of sight, to illustrate the potential seriousness of contamination of the weak lensing signal by these unrelated structures.

  8. Structural properties of small rhodium clusters

    SciTech Connect (OSTI)

    Soon, Yee Yeen; Yoon, Tiem Leong; Lim, Thong Leng

    2015-04-24

    We report a systematic study of the structural properties of rhodium clusters at the atomistic level. A novel global-minimum search algorithm, known as parallel tempering multicanonical basin hopping plus genetic algorithm (PTMBHGA), is used to obtain the geometrical structures with lowest minima at the semi-empirical level where Gupta potential is used to describe the atomic interaction among the rhodium atoms. These structures are then re-optimized at the density functional theory (DFT) level with exchange-correlation energy approximated by Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA). The structures are optimized for different spin multiplicities. The ones with lowest energies will be taken as ground-state structures. In most cases, we observe only minor changes in the geometry and bond length of the clusters as a result of DFT-level re-optimization. Only in some limited cases, the initial geometries obtained from the PTMBHGA are modified by the re-optimization. The variation of structural properties, such as ground-state geometry, symmetry and binding energy, with respect to the cluster size is studied and agreed well with other results available in the literature.

  9. Thermal entanglement of spins in mean-field clusters

    SciTech Connect (OSTI)

    Asoudeh, M.; Karimipour, V.

    2006-06-15

    We determine thermal entanglement in mean-field clusters of N spin one-half particles interacting via the anisotropic Heisenberg interaction, with and without external magnetic field. For the xxx cluster in the absence of magnetic field we prove that only the N=2 ferromagnetic cluster shows entanglement. An external magnetic field B can only entangle xxx antiferromagnetic clusters in certain regions of the B-T plane. On the other hand, the xxz clusters of size N>2 are entangled only when the interaction is ferromagnetic. Detailed dependence of the entanglement on various parameters is investigated in each case.

  10. Incremental Clustering Algorithm For Earth Science Data Mining

    SciTech Connect (OSTI)

    Vatsavai, Raju

    2009-01-01

    Remote sensing data plays a key role in understanding the complex geographic phenomena. Clustering is a useful tool in discovering interesting patterns and structures within the multivariate geospatial data. One of the key issues in clustering is the specication of appropriate number of clusters, which is not obvious in many practical situations. In this paper we provide an extension of G-means algorithm which automatically learns the number of clusters present in the data and avoids over estimation of the number of clusters. Experimental evaluation on simulated and remotely sensed image data shows the effectiveness of our algorithm.

  11. Site Monitoring Area Maps

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

    The spatial location and boundaries for each Site shown on the Site Monitoring Area maps ... P-SMA-2 DP-SMA-0.4 LA-SMA-2.3 LA-SMA-5.51 LA-SMA-6.38 P-SMA-2.15 DP-SMA-0.6 ...

  12. Plutonium focus area

    SciTech Connect (OSTI)

    1996-08-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this new approach, EM developed a management structure and principles that led to the creation of specific Focus Areas. These organizations were designed to focus the scientific and technical talent throughout DOE and the national scientific community on the major environmental restoration and waste management problems facing DOE. The Focus Area approach provides the framework for intersite cooperation and leveraging of resources on common problems. After the original establishment of five major Focus Areas within the Office of Technology Development (EM-50, now called the Office of Science and Technology), the Nuclear Materials Stabilization Task Group (EM-66) followed the structure already in place in EM-50 and chartered the Plutonium Focus Area (PFA). The following information outlines the scope and mission of the EM, EM-60, and EM-66 organizations as related to the PFA organizational structure.

  13. Subsurface contaminants focus area

    SciTech Connect (OSTI)

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  14. Estimating f{sub NL} and g{sub NL} from massive high-redshift galaxy clusters

    SciTech Connect (OSTI)

    Enqvist, Kari; Hotchkiss, Shaun; Taanila, Olli E-mail: shaun.hotchkiss@helsinki.fi

    2011-04-01

    There are observations of at least 14 high-redshift massive galaxy clusters, which have an extremely small probability with a purely Gaussian initial curvature perturbation. Here we revisit the estimation of the contribution of non-Gaussianities to the cluster mass function and point out serious problems that have resulted from the application of the mass function out of the range of its validity. We remedy the situation and show that the values of f{sub NL} previously claimed to completely reconcile (i.e. at ∼ 100% confidence) the existence of the clusters with ΛCDM are unphysically small. However, for WMAP cosmology and at 95% confidence, we arrive at the limit f{sub NL}∼>411, which is similar to previous estimates. We also explore the possibility of a large g{sub NL} as the reason for the observed excess of the massive galaxy clusters. This scenario, g{sub NL} > 2 × 10{sup 6}, appears to be in more agreement with CMB and LSS limits for the non-Gaussianity parameters and could also provide an explanation for the overabundance of large voids in the early universe.

  15. Rotational and radial velocities of 1.3-2.2 M {sub ☉} red giants in open clusters

    SciTech Connect (OSTI)

    Carlberg, Joleen K.

    2014-06-01

    This study presents the rotational distribution of red giant (RG) stars in 11 old to intermediate age open clusters. The masses of these stars are all above the Kraft break, so they lose negligible amounts of their birth angular momentum (AM) during the main-sequence (MS) evolution. However, they do span a mass range with quite different AM distributions imparted during formation, with the stars less massive than ∼1.6M {sub ☉} arriving on the MS with lower rotation rates than the more massive stars. The majority of RGs in this study are slow rotators across the entire red giant branch regardless of mass, supporting the picture that intermediate-mass stars rapidly spin down when they evolve off the MS and develop convection zones capable of driving a magnetic dynamo. Nevertheless, a small fraction of RGs in open clusters show some level of enhanced rotation, and faster rotators are as common in these clusters as in the field RG population. Most of these enhanced rotators appear to be red clump stars, which is also true of the underlying stellar sample, while others are clearly RGs that are above or below the clump. In addition to rotational velocities, the radial velocities (RVs) and membership probabilities of individual stars are also presented. Cluster heliocentric RVs for NGC 6005 and Pismis 18 are reported for the first time.

  16. Comparison of galaxy clusters selected by weak-lensing, optical spectroscopy, and X-rays in the deep lens survey F2 field

    SciTech Connect (OSTI)

    Starikova, Svetlana; Jones, Christine; Forman, William R.; Vikhlinin, Alexey; Kurtz, Michael J.; Fabricant, Daniel G.; Murray, Stephen S.; Geller, Margaret J.; Dell'Antonio, Ian P.

    2014-05-10

    We compare galaxy clusters selected in Chandra and XMM-Newton X-ray observations of the 4 deg{sup 2} Deep Lens Survey (DLS) F2 field to the cluster samples previously selected in the same field from a sensitive weak-lensing shear map derived from the DLS and from a detailed galaxy redshift surveythe Smithsonian Hectospec Lensing Survey (SHELS). Our Chandra and XMM-Newton observations cover 1.6 deg{sup 2} of the DLS F2 field, including all 12 weak-lensing peaks above a signal-to-noise ratio of 3.5, along with 16 of the 20 SHELS clusters with published velocity dispersions >500 km s{sup 1}. We detect 26 extended X-ray sources in this area and confirm 23 of them as galaxy clusters using the optical imaging. Approximately 75% of clusters detected in either X-ray or spectroscopic surveys are found in both; these follow the previously established scaling relations between velocity dispersion, L {sub X}, and T {sub X}. A lower percentage, 60%, of clusters are in common between X-ray and DLS samples. With the exception of a high false-positive rate in the DLS weak-lensing search (5 out of 12 DLS candidates appear to be false), differences between the three cluster detection methods can be attributed primarily to observational uncertainties and intrinsic scatter between different observables and cluster mass.

  17. GLOBULAR CLUSTER SYSTEMS IN BRIGHTEST CLUSTER GALAXIES: A NEAR-UNIVERSAL LUMINOSITY FUNCTION?

    SciTech Connect (OSTI)

    Harris, William E.; O'Halloran, Heather; Cockcroft, Robert E-mail: ohallohm@mcmaster.ca; and others

    2014-12-20

    We present the first results from our Hubble Space Telescope brightest cluster galaxy (BCG) survey of seven central supergiant cluster galaxies and their globular cluster (GC) systems. We measure a total of 48,000 GCs in all seven galaxies, representing the largest single GC database. We find that a log-normal shape accurately matches the observed the luminosity function (LF) of the GCs down to the globular cluster luminosity function turnover point, which is near our photometric limit. In addition, the LF has a virtually identical shape in all seven galaxies. Our data underscore the similarity in the formation mechanism of massive star clusters in diverse galactic environments. At the highest luminosities (L ? 10{sup 7} L {sub ?}), we find small numbers of ''superluminous'' objects in five of the galaxies; their luminosity and color ranges are at least partly consistent with those of ultra-compact dwarfs. Last, we find preliminary evidence that in the outer halo (R ? 20kpc), the LF turnover point shows a weak dependence on projected distance, scaling as L {sub 0} ? R {sup 0.2}, while the LF dispersion remains nearly constant.

  18. THE STRUCTURE OF THE STAR-FORMING CLUSTER RCW 38

    SciTech Connect (OSTI)

    Winston, E.; Wolk, S. J.; Bourke, T. L.; Spitzbart, B.; Megeath, S. T.; Gutermuth, R.

    2011-12-20

    We present a study of the structure of the high-mass star-forming region RCW 38 and the spatial distribution of its young stellar population. Spitzer Infrared Array Camera (IRAC) photometry (3-8 {mu}m) is combined with Two Micron All Sky Survey near-IR data to identify young stellar objects (YSOs) by IR-excess emission from their circumstellar material. Chandra X-ray data are used to identify class III pre-main-sequence stars lacking circumstellar material. We identify 624 YSOs: 23 class 0/I and 90 flat spectrum protostars, 437 class II stars, and 74 class III stars. We also identify 29 (27 new) O star candidates over the IRAC field. Seventy-two stars exhibit IR-variability, including 7 class 0/I and 12 flat spectrum YSOs. A further 177 tentative candidates are identified by their location in the IRAC [3.6] versus [3.6]-[5.8] color-magnitude diagram. We find strong evidence of subclustering in the region. Three subclusters were identified surrounding the central cluster, with massive and variable stars in each subcluster. The central region shows evidence of distinct spatial distributions of the protostars and pre-main-sequence stars. A previously detected IR cluster, DB2001{sub O}bj36, has been established as a subcluster of RCW 38. This suggests that star formation in RCW 38 occurs over a more extended area than previously thought. The gas-to-dust ratio is examined using the X-ray derived hydrogen column density, N{sub H} and the K-band extinction, and found to be consistent with the diffuse interstellar medium, in contrast with Serpens and NGC 1333. We posit that the high photoionizing flux of massive stars in RCW 38 affects the agglomeration of the dust grains.

  19. Superfluid response of two-dimensional parahydrogen clusters in confinement

    SciTech Connect (OSTI)

    Idowu, Saheed; Boninsegni, Massimo

    2015-04-07

    We study by computer simulations the effect of confinement on the superfluid properties of small two-dimensional (2D) parahydrogen clusters. For clusters of fewer than twenty molecules, the superfluid response in the low temperature limit is found to remain comparable in magnitude to that of free clusters, within a rather wide range of depth and size of the confining well. The resilience of the superfluid response is attributable to the “supersolid” character of these clusters. We investigate the possibility of establishing a bulk 2D superfluid “cluster crystal” phase of p-H{sub 2}, in which a global superfluid response would arise from tunnelling of molecules across adjacent unit cells. The computed energetics suggests that for clusters of about ten molecules, such a phase may be thermodynamically stable against the formation of the equilibrium insulating crystal, for values of the cluster crystal lattice constant possibly allowing tunnelling across adjacent unit cells.

  20. Mineral resources of the North Algodones Dunes Wilderness Study Area (CDCA-360), Imperial County, California

    SciTech Connect (OSTI)

    Smith, R.S.U.; Yeend, W.; Dohrenwend, J.C.; Gese, D.D.

    1984-01-01

    This report presents the results of a mineral survey of the North Algodones Dunes Wilderness Study Area (CDCA-360), California Desert Conservation Area, Imperial County, California. The potential for undiscovered base and precious metals, and sand and gravel within the North Algodones Dunes Wilderness Study Area is low. The study area has a moderate potential for geothermal energy. One small sand-free area between the Coachella Canal and the west edge of the dune field would probably be the only feasible exploration site for geothermal energy. The study area has a moderate to high potential for the occurrence of undiscovered gas/condensate within the underlying rocks. 21 refs.

  1. CATCH ME IF YOU CAN: IS THERE A 'RUNAWAY-MASS' BLACK HOLE IN THE ORION NEBULA CLUSTER?

    SciTech Connect (OSTI)

    Subr, Ladislav; Kroupa, Pavel; Baumgardt, Holger

    2012-09-20

    We investigate the dynamical evolution of the Orion Nebula Cluster (ONC) by means of direct N-body integrations. A large fraction of residual gas was probably expelled when the ONC formed, so we assume that the ONC was much more compact when it formed compared with its current size, in agreement with the embedded cluster radius-mass relation from Marks and Kroupa. Hence, we assume that few-body relaxation played an important role during the initial phase of evolution of the ONC. In particular, three-body interactions among OB stars likely led to their ejection from the cluster and, at the same time, to the formation of a massive object via 'runaway' physical stellar collisions. The resulting depletion of the high-mass end of the stellar mass function in the cluster is one of the important points where our models fit the observational data. We speculate that the runaway-mass star may have collapsed directly into a massive black hole (M{sub .} {approx}> 100 M{sub Sun }). Such a dark object could explain the large velocity dispersion of the four Trapezium stars observed in the ONC core. We further show that the putative massive black hole is likely to be a member of a binary system with Almost-Equal-To 70% probability. In such a case, it could be detected either due to short periods of enhanced accretion of stellar winds from the secondary star during pericentre passages, or through a measurement of the motion of the secondary whose velocity would exceed 10 km s{sup -1} along the whole orbit.

  2. First-principles investigation of the dissociation and coupling of methane on small copper clusters: Interplay of collision dynamics and geometric and electronic effects

    SciTech Connect (OSTI)

    Varghese, Jithin J.; Mushrif, Samir H.

    2015-05-14

    Small metal clusters exhibit unique size and morphology dependent catalytic activity. The search for alternate minimum energy pathways and catalysts to transform methane to more useful chemicals and carbon nanomaterials led us to investigate collision induced dissociation of methane on small Cu clusters. We report here for the first time, the free energy barriers for the collision induced activation, dissociation, and coupling of methane on small Cu clusters (Cu{sub n} where n = 2–12) using ab initio molecular dynamics and metadynamics simulations. The collision induced activation of the stretching and bending vibrations of methane significantly reduces the free energy barrier for its dissociation. Increase in the cluster size reduces the barrier for dissociation of methane due to the corresponding increase in delocalisation of electron density within the cluster, as demonstrated using the electron localisation function topology analysis. This enables higher probability of favourable alignment of the C–H stretching vibration of methane towards regions of high electron density within the cluster and makes higher number of sites available for the chemisorption of CH{sub 3} and H upon dissociation. These characteristics contribute in lowering the barrier for dissociation of methane. Distortion and reorganisation of cluster geometry due to high temperature collision dynamics disturb electron delocalisation within them and increase the barrier for dissociation. Coupling reactions of CH{sub x} (x = 1–3) species and recombination of H with CH{sub x} have free energy barriers significantly lower than complete dehydrogenation of methane to carbon. Thus, competition favours the former reactions at high hydrogen saturation on the clusters.

  3. Locally Renormalized Coupled-Cluster Equations for Singly and Doubly Excited Clusters

    SciTech Connect (OSTI)

    Kowalski, Karol

    2006-07-10

    The Numerator-Denominator Connected (NDC) Expansion for the Coupled-Cluster (CC) method [K. Kowalski, P. Piecuch, J. Chem. Phys. 122 (2005) 074107], is used to construct a new set of stationary conditions for approximate coupled-cluster approaches. Several CC approximations based on models involving singles and doubles (CCSD) as well as singles, doubles, and triples (CCSDT) are developed and discussed in the context of ground-state applications. The resulting locally-renormalized CCSD (LR-CCSD) and CCSDT (LR-CCSDT) equations are shown to regularize the expressions for the cluster amplitudes in the challenging situations that occur when the orbital energy differences approach zero. Affordable schemes for handling the local denominators (all-holes-Jn coupling), that naturally appear in locally renormalized formalisms, are also discussed.

  4. Property:AreaGeology | Open Energy Information

    Open Energy Info (EERE)

    Geothermal Area B Beowawe Hot Springs Geothermal Area Blue Mountain Geothermal Area Brady Hot Springs Geothermal Area C Chena Geothermal Area Coso Geothermal Area D Desert Peak...

  5. Weighing galaxy clusters with gas. II. On the origin of hydrostatic mass bias in ?CDM galaxy clusters

    SciTech Connect (OSTI)

    Nelson, Kaylea; Nagai, Daisuke; Yu, Liang; Lau, Erwin T.; Rudd, Douglas H.

    2014-02-20

    The use of galaxy clusters as cosmological probes hinges on our ability to measure their masses accurately and with high precision. Hydrostatic mass is one of the most common methods for estimating the masses of individual galaxy clusters, which suffer from biases due to departures from hydrostatic equilibrium. Using a large, mass-limited sample of massive galaxy clusters from a high-resolution hydrodynamical cosmological simulation, in this work we show that in addition to turbulent and bulk gas velocities, acceleration of gas introduces biases in the hydrostatic mass estimate of galaxy clusters. In unrelaxed clusters, the acceleration bias is comparable to the bias due to non-thermal pressure associated with merger-induced turbulent and bulk gas motions. In relaxed clusters, the mean mass bias due to acceleration is small (? 3%), but the scatter in the mass bias can be reduced by accounting for gas acceleration. Additionally, this acceleration bias is greater in the outskirts of higher redshift clusters where mergers are more frequent and clusters are accreting more rapidly. Since gas acceleration cannot be observed directly, it introduces an irreducible bias for hydrostatic mass estimates. This acceleration bias places limits on how well we can recover cluster masses from future X-ray and microwave observations. We discuss implications for cluster mass estimates based on X-ray, Sunyaev-Zel'dovich effect, and gravitational lensing observations and their impact on cluster cosmology.

  6. Modeling the formation of globular cluster systems in the Virgo cluster

    SciTech Connect (OSTI)

    Li, Hui; Gnedin, Oleg Y. E-mail: ognedin@umich.edu

    2014-11-20

    The mass distribution and chemical composition of globular cluster (GC) systems preserve fossil record of the early stages of galaxy formation. The observed distribution of GC colors within massive early-type galaxies in the ACS Virgo Cluster Survey (ACSVCS) reveals a multi-modal shape, which likely corresponds to a multi-modal metallicity distribution. We present a simple model for the formation and disruption of GCs that aims to match the ACSVCS data. This model tests the hypothesis that GCs are formed during major mergers of gas-rich galaxies and inherit the metallicity of their hosts. To trace merger events, we use halo merger trees extracted from a large cosmological N-body simulation. We select 20 halos in the mass range of 2 10{sup 12} to 7 10{sup 13} M {sub ?} and match them to 19 Virgo galaxies with K-band luminosity between 3 10{sup 10} and 3 10{sup 11} L {sub ?}. To set the [Fe/H] abundances, we use an empirical galaxy mass-metallicity relation. We find that a minimal merger ratio of 1:3 best matches the observed cluster metallicity distribution. A characteristic bimodal shape appears because metal-rich GCs are produced by late mergers between massive halos, while metal-poor GCs are produced by collective merger activities of less massive hosts at early times. The model outcome is robust to alternative prescriptions for cluster formation rate throughout cosmic time, but a gradual evolution of the mass-metallicity relation with redshift appears to be necessary to match the observed cluster metallicities. We also affirm the age-metallicity relation, predicted by an earlier model, in which metal-rich clusters are systematically several billion younger than their metal-poor counterparts.

  7. Photon assisted processes: Probability amplitudes for the absorption and emission of photons and dc-photocurrents

    SciTech Connect (OSTI)

    Micu, C.; Racolta, D.; Papp, E.

    2014-11-24

    In this paper one deals with the derivation of probability amplitudes characterizing the photon assisted injection of electrons in a two-terminal quantum conductor. For this purpose one accounts for spatially constant but time dependent periodic voltages applied on an Ohmic contact. Resorting to the discrete Fourier transform provides the probability amplitudes for the emission and absorption of photons in terms of squared Bessel functions of the first kind and integer order. Several kinds of ac-pulses like sinusoidal and dc+sinusoidal are assumed. Mean square values concerning photon numbers have been discussed in some more detail. Time averages of squared time dependent classical currents and leading corrections to the rescaled dc-photocurrent have also been accounted for.

  8. Probability-Based Software for Grid Optimization: Improved Power System Operations Using Advanced Stochastic Optimization

    SciTech Connect (OSTI)

    2012-02-24

    GENI Project: Sandia National Laboratories is working with several commercial and university partners to develop software for market management systems (MMSs) that enable greater use of renewable energy sources throughout the grid. MMSs are used to securely and optimally determine which energy resources should be used to service energy demand across the country. Contributions of electricity to the grid from renewable energy sources such as wind and solar are intermittent, introducing complications for MMSs, which have trouble accommodating the multiple sources of price and supply uncertainties associated with bringing these new types of energy into the grid. Sandia’s software will bring a new, probability-based formulation to account for these uncertainties. By factoring in various probability scenarios for electricity production from renewable energy sources in real time, Sandia’s formula can reduce the risk of inefficient electricity transmission, save ratepayers money, conserve power, and support the future use of renewable energy.

  9. Stellar age spreads in clusters as imprints of cluster-parent clump densities

    SciTech Connect (OSTI)

    Parmentier, G.; Grebel, E. K.; Pfalzner, S.

    2014-08-20

    It has recently been suggested that high-density star clusters have stellar age distributions much narrower than that of the Orion Nebula Cluster, indicating a possible trend of narrower age distributions for denser clusters. We show this effect to likely arise from star formation being faster in gas with a higher density. We model the star formation history of molecular clumps in equilibrium by associating a star formation efficiency per free-fall time, ?{sub ff}, to their volume density profile. We focus on the case of isothermal spheres and we obtain the evolution with time of their star formation rate. Our model predicts a steady decline of the star formation rate, which we quantify with its half-life time, namely, the time needed for the star formation rate to drop to half its initial value. Given the uncertainties affecting the star formation efficiency per free-fall time, we consider two distinct values: ?{sub ff} = 0.1 and ?{sub ff} = 0.01. When ?{sub ff} = 0.1, the half-life time is of the order of the clump free-fall time, ?{sub ff}. As a result, the age distributions of stars formed in high-density clumps have smaller full-widths at half-maximum than those of stars formed in low-density clumps. When the star formation efficiency per free-fall time is 0.01, the half-life time is 10 times longer, i.e., 10 clump free-fall times. We explore what happens if the duration of star formation is shorter than 10?{sub ff}, that is, if the half-life time of the star formation rate cannot be defined. There, we build on the invariance of the shape of the young cluster mass function to show that an anti-correlation between the clump density and the duration of star formation is expected. We therefore conclude that, regardless of whether the duration of star formation is longer than the star formation rate half-life time, denser molecular clumps yield narrower star age distributions in clusters. Published densities and stellar age spreads of young clusters and star

  10. SALTSTONE DISPOSAL FACILITY: DETERMINATION OF THE PROBABLE MAXIMUM WATER TABLE ELEVATION

    SciTech Connect (OSTI)

    Hiergesell, R

    2005-04-01

    A coverage depicting the configuration of the probable maximum water table elevation in the vicinity of the Saltstone Disposal Facility (SDF) was developed to support the Saltstone program. This coverage is needed to support the construction of saltstone vaults to assure that they remain above the maximum elevation of the water table during the Performance Assessment (PA) period of compliance. A previous investigation to calculate the historical high water table beneath the SDF (Cook, 1983) was built upon to incorporate new data that has since become available to refine that estimate and develop a coverage that could be extended to the perennial streams adjacent to the SDF. This investigation incorporated the method used in the Cook, 1983 report to develop an estimate of the probable maximum water table for a group of wells that either existed at one time at or near the SDF or which currently exist. Estimates of the probable maximum water table at these wells were used to construct 2D contour lines depicting this surface beneath the SDF and extend them to the nearby hydrologic boundaries at the perennial streams adjacent to the SDF. Although certain measures were implemented to assure that the contour lines depict a surface above which the water table will not rise, the exact elevation of this surface cannot be known with complete certainty. It is therefore recommended that the construction of saltstone vaults incorporate a vertical buffer of at least 5-feet between the base of the vaults and the depicted probable maximum water table elevation. This should provide assurance that the water table under the wet extreme climatic condition will never rise to intercept the base of a vault.

  11. Efficient Probability of Failure Calculations for QMU using Computational Geometry LDRD 13-0144 Final Report

    SciTech Connect (OSTI)

    Mitchell, Scott A.; Ebeida, Mohamed Salah; Romero, Vicente J.; Swiler, Laura Painton; Rushdi, Ahmad A.; Abdelkader, Ahmad

    2015-09-01

    This SAND report summarizes our work on the Sandia National Laboratory LDRD project titled "Efficient Probability of Failure Calculations for QMU using Computational Geometry" which was project #165617 and proposal #13-0144. This report merely summarizes our work. Those interested in the technical details are encouraged to read the full published results, and contact the report authors for the status of the software and follow-on projects.

  12. Coupled escape probability for an asymmetric spherical case: Modeling optically thick comets

    SciTech Connect (OSTI)

    Gersch, Alan M.; A'Hearn, Michael F.

    2014-05-20

    We have adapted Coupled Escape Probability, a new exact method of solving radiative transfer problems, for use in asymmetrical spherical situations. Our model is intended specifically for use in modeling optically thick cometary comae, although not limited to such use. This method enables the accurate modeling of comets' spectra even in the potentially optically thick regions nearest the nucleus, such as those seen in Deep Impact observations of 9P/Tempel 1 and EPOXI observations of 103P/Hartley 2.

  13. Figure 1. Project Area, Focused Study Area, Potential Access...

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

    Page 4 of 8 Figure 1. Project Area, Focused Study Area, Potential Access Agreement Land, and Land Not Suitable for Conveyance

  14. Figure 1. Project Area, Focused Study Area, Potential Access...

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

    Page 4 of 8 Figure 1. Project Area, Focused Study Area, Potential Access Agreement Land, and Land Not Suitable for Conveyance...

  15. ON THE CONNECTION BETWEEN GIANT RADIO HALOS AND CLUSTER MERGERS

    SciTech Connect (OSTI)

    Cassano, R.; Giacintucci, S.; Brunetti, G.; Venturi, T.

    2010-10-01

    The frequently observed association between giant radio halos (RHs) and merging galaxy clusters has driven present theoretical models of non-thermal emission from galaxy clusters, which are based on the idea that the energy dissipated during cluster-cluster mergers could power the formation of RHs. To quantitatively test the merger-halo connection, we present the first statistical study based on deep radio data and X-ray observations of a complete X-ray-selected sample of galaxy clusters with X-ray luminosity {>=}5 x 10{sup 44} erg s{sup -1} and redshift 0.2 {<=} z {<=} 0.32. Using several methods to characterize cluster substructures, namely, the power ratios, centroid shift, and X-ray brightness concentration parameter, we show that clusters with and without RH can be quantitatively differentiated in terms of their dynamical properties. In particular, we confirm that RHs are associated with dynamically disturbed clusters and clusters without RH are more 'relaxed', with only a couple of exceptions where a disturbed cluster does not exhibit a halo.

  16. MOCK OBSERVATIONS OF BLUE STRAGGLERS IN GLOBULAR CLUSTER MODELS

    SciTech Connect (OSTI)

    Sills, Alison; Glebbeek, Evert; Chatterjee, Sourav; Rasio, Frederic A. E-mail: e.glebbeek@astro.ru.nl E-mail: rasio@northwestern.edu

    2013-11-10

    We created artificial color-magnitude diagrams of Monte Carlo dynamical models of globular clusters and then used observational methods to determine the number of blue stragglers in those clusters. We compared these blue stragglers to various cluster properties, mimicking work that has been done for blue stragglers in Milky Way globular clusters to determine the dominant formation mechanism(s) of this unusual stellar population. We find that a mass-based prescription for selecting blue stragglers will select approximately twice as many blue stragglers than a selection criterion that was developed for observations of real clusters. However, the two numbers of blue stragglers are well-correlated, so either selection criterion can be used to characterize the blue straggler population of a cluster. We confirm previous results that the simplified prescription for the evolution of a collision or merger product in the BSE code overestimates their lifetimes. We show that our model blue stragglers follow similar trends with cluster properties (core mass, binary fraction, total mass, collision rate) as the true Milky Way blue stragglers as long as we restrict ourselves to model clusters with an initial binary fraction higher than 5%. We also show that, in contrast to earlier work, the number of blue stragglers in the cluster core does have a weak dependence on the collisional parameter ? in both our models and in Milky Way globular clusters.

  17. ULTRA-COMPACT DWARFS IN THE COMA CLUSTER

    SciTech Connect (OSTI)

    Chiboucas, Kristin; Tully, R. Brent; Marzke, R. O.; Phillipps, S.; Price, J.; Peng, Eric W.; Trentham, Neil; Carter, David; Hammer, Derek E-mail: tully@ifa.hawaii.edu E-mail: S.Phillipps@bristol.ac.uk E-mail: peng@pku.edu.cn E-mail: dxc@astro.livjm.ac.uk

    2011-08-20

    We have undertaken a spectroscopic search for ultra-compact dwarf galaxies (UCDs) in the dense core of the dynamically evolved, massive Coma cluster as part of the Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) Coma Cluster Treasury Survey. UCD candidates were initially chosen based on color, magnitude, degree of resolution within the ACS images, and the known properties of Fornax and Virgo UCDs. Follow-up spectroscopy with Keck/Low-Resolution Imaging Spectrometer confirmed 27 candidates as members of the Coma cluster, a success rate >60% for targeted objects brighter than M{sub R} = -12. Another 14 candidates may also prove to be Coma members, but low signal-to-noise spectra prevent definitive conclusions. An investigation of the properties and distribution of the Coma UCDs finds these objects to be very similar to UCDs discovered in other environments. The Coma UCDs tend to be clustered around giant galaxies in the cluster core and have colors/metallicity that correlate with the host galaxy. With properties and a distribution similar to that of the Coma cluster globular cluster population, we find strong support for a star cluster origin for the majority of the Coma UCDs. However, a few UCDs appear to have stellar population or structural properties which differentiate them from the old star cluster populations found in the Coma cluster, perhaps indicating that UCDs may form through multiple formation channels.

  18. Cluster computing software for GATE simulations

    SciTech Connect (OSTI)

    Beenhouwer, Jan de; Staelens, Steven; Kruecker, Dirk; Ferrer, Ludovic; D'Asseler, Yves; Lemahieu, Ignace; Rannou, Fernando R.

    2007-06-15

    Geometry and tracking (GEANT4) is a Monte Carlo package designed for high energy physics experiments. It is used as the basis layer for Monte Carlo simulations of nuclear medicine acquisition systems in GEANT4 Application for Tomographic Emission (GATE). GATE allows the user to realistically model experiments using accurate physics models and time synchronization for detector movement through a script language contained in a macro file. The downside of this high accuracy is long computation time. This paper describes a platform independent computing approach for running GATE simulations on a cluster of computers in order to reduce the overall simulation time. Our software automatically creates fully resolved, nonparametrized macros accompanied with an on-the-fly generated cluster specific submit file used to launch the simulations. The scalability of GATE simulations on a cluster is investigated for two imaging modalities, positron emission tomography (PET) and single photon emission computed tomography (SPECT). Due to a higher sensitivity, PET simulations are characterized by relatively high data output rates that create rather large output files. SPECT simulations, on the other hand, have lower data output rates but require a long collimator setup time. Both of these characteristics hamper scalability as a function of the number of CPUs. The scalability of PET simulations is improved here by the development of a fast output merger. The scalability of SPECT simulations is improved by greatly reducing the collimator setup time. Accordingly, these two new developments result in higher scalability for both PET and SPECT simulations and reduce the computation time to more practical values.

  19. Technique for fast and efficient hierarchical clustering

    DOE Patents [OSTI]

    Stork, Christopher

    2013-10-08

    A fast and efficient technique for hierarchical clustering of samples in a dataset includes compressing the dataset to reduce a number of variables within each of the samples of the dataset. A nearest neighbor matrix is generated to identify nearest neighbor pairs between the samples based on differences between the variables of the samples. The samples are arranged into a hierarchy that groups the samples based on the nearest neighbor matrix. The hierarchy is rendered to a display to graphically illustrate similarities or differences between the samples.

  20. Visual Matrix Clustering of Social Networks

    SciTech Connect (OSTI)

    Wong, Pak C.; Mackey, Patrick S.; Foote, Harlan P.; May, Richard A.

    2013-07-01

    The prevailing choices to graphically represent a social network in todays literature are a node-link graph layout and an adjacency matrix. Both visualization techniques have unique strengths and weaknesses when applied to different domain applications. In this article, we focus our discussion on adjacency matrix and how to turn the matrix-based visualization technique from merely showing pairwise associations among network actors (or graph nodes) to depicting clusters of a social network. We also use node-link layouts to supplement the discussion.

  1. Synergy between pair coupled cluster doubles and pair density functional theory

    SciTech Connect (OSTI)

    Garza, Alejandro J.; Bulik, Ireneusz W.; Henderson, Thomas M.; Scuseria, Gustavo E.

    2015-01-28

    Pair coupled cluster doubles (pCCD) has been recently studied as a method capable of accounting for static correlation with low polynomial cost. We present three combinations of pCCD with KohnSham functionals of the density and on-top pair density (the probability of finding two electrons on top of each other) to add dynamic correlation to pCCD without double counting. With a negligible increase in computational cost, these pCCD+DFT blends greatly improve upon pCCD in the description of typical problems where static and dynamic correlations are both important. We argue thatas a black-box method with low scaling, size-extensivity, size-consistency, and a simple quasidiagonal two-particle density matrixpCCD is an excellent match for pair density functionals in this type of fusion of multireference wavefunctions with DFT.

  2. Large area bulk superconductors

    DOE Patents [OSTI]

    Miller, Dean J.; Field, Michael B.

    2002-01-01

    A bulk superconductor having a thickness of not less than about 100 microns is carried by a polycrystalline textured substrate having misorientation angles at the surface thereof not greater than about 15.degree.; the bulk superconductor may have a thickness of not less than about 100 microns and a surface area of not less than about 50 cm.sup.2. The textured substrate may have a thickness not less than about 10 microns and misorientation angles at the surface thereof not greater than about 15.degree.. Also disclosed is a process of manufacturing the bulk superconductor and the polycrystalline biaxially textured substrate material.

  3. Comment on “Measurement of two- and three-nucleon short-range correlation probabilities in nuclei”

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

    Higinbotham, Douglas W.; Hen, Or

    2015-04-24

    Comment on 'Measurement of 2- and 3-nucleon short range correlation probabilities in nuclei' shows how the reported three-nucleon plateau was likely due to resolution effects.

  4. Migration of defect clusters and xenon-vacancy clusters in uranium dioxide

    SciTech Connect (OSTI)

    Chen, Dong; Gao, Fei; Deng, Huiqiu; Hu, Wangyu; Sun, Xin

    2014-07-01

    The possible transition states, minimum energy paths and migration mechanisms of defect clusters and xenon-vacancy defect clusters in uranium dioxide have been investigated using the dimer and the nudged elastic-band methods. The nearby O atom can easily hop into the oxygen vacancy position by overcoming a small energy barrier, which is much lower than that for the migration of a uranium vacancy. A simulation for a vacancy cluster consisting of two oxygen vacancies reveals that the energy barrier of the divacancy migration tends to decrease with increasing the separation distance of divacancy. For an oxygen interstitial, the migration barrier for the hopping mechanism is almost three times larger than that for the exchange mechanism. Xe moving between two interstitial sites is unlikely a dominant migration mechanism considering the higher energy barrier. A net migration process of a Xe-vacancy pair containing an oxygen vacancy and a xenon interstitial is identified by the NEB method. We expect the oxygen vacancy-assisted migration mechanism to possibly lead to a long distance migration of the Xe interstitials in UO2. The migration of defect clusters involving Xe substitution indicates that Xe atom migrating away from the uranium vacancy site is difficult.

  5. MEASURING THE ULTIMATE HALO MASS OF GALAXY CLUSTERS: REDSHIFTS AND MASS PROFILES FROM THE HECTOSPEC CLUSTER SURVEY (HeCS)

    SciTech Connect (OSTI)

    Rines, Kenneth; Geller, Margaret J.; Kurtz, Michael J.; Diaferio, Antonaldo E-mail: diaferio@ph.unito.it

    2013-04-10

    The infall regions of galaxy clusters represent the largest gravitationally bound structures in a {Lambda}CDM universe. Measuring cluster mass profiles into the infall regions provides an estimate of the ultimate mass of these halos. We use the caustic technique to measure cluster mass profiles from galaxy redshifts obtained with the Hectospec Cluster Survey (HeCS), an extensive spectroscopic survey of galaxy clusters with MMT/Hectospec. We survey 58 clusters selected by X-ray flux at 0.1 < z < 0.3. The survey includes 22,680 unique MMT/Hectospec redshifts for individual galaxies; 10,145 of these galaxies are cluster members. For each cluster, we acquired high signal-to-noise spectra for {approx}200 cluster members and a comparable number of foreground/background galaxies. The cluster members trace out infall patterns around the clusters. The members define a very narrow red sequence. We demonstrate that the determination of velocity dispersion is insensitive to the inclusion of bluer members (a small fraction of the cluster population). We apply the caustic technique to define membership and estimate the mass profiles to large radii. The ultimate halo mass of clusters (the mass that remains bound in the far future of a {Lambda}CDM universe) is on average (1.99 {+-} 0.11)M{sub 200}, a new observational cosmological test in essential agreement with simulations. Summed profiles binned in M{sub 200} and in L{sub X} demonstrate that the predicted Navarro-Frenk-White form of the density profile is a remarkably good representation of the data in agreement with weak lensing results extending to large radius. The concentration of these summed profiles is also consistent with theoretical predictions.

  6. Investigating the Correspondence Between Transcriptomic and Proteomic Expression Profiles Using Coupled Cluster Models.

    SciTech Connect (OSTI)

    Rogers, Simon; Girolami, Mark; Kolch, Walter; Waters, Katrina M.; Liu, Tao; Thrall, Brian D.; Wiley, H. S.

    2008-12-01

    Modern transcriptomics and proteomics enable us to survey the expression of RNAs and proteins at large scales. While these data are usually generated and analysed separately, there is an increasing interest in comparing and co-analysing transcriptome and proteome expression data. A major open question is whether transcriptome and proteome expression is linked and how it is coordinated. Results: Here we have developed a probabilistic clustering model that permits analysis of the links between transcriptomic and proteomic profiles in a sensible and flexible manner. Our coupled mixture model defines a prior probability distribution over the component to which a protein profile should be assigned conditioned on which component the associated mRNA profile belongs to. By providing probabilistic assignments this approach sits between the two extremes of concatenating the data on the assumption that mRNA and protein clusters would have a one-to-one relationship, and independent clustering where the mRNA profile provides no information on the protein profile and vice-versa. We apply this approach to a large dataset of quantitative transcriptomic and proteomic expression data obtained from a human breast epithelial cell line (HMEC) stimulated by epidermal growth factor (EGF) over a series of timepoints corresponding to one cell cycle. The results reveal a complex relationship between transcriptome and proteome with most mRNA clusters linked to at least two protein clusters, and vice versa. A more detailed analysis incorporating information on gene function from the gene ontology database shows that a high correlation of mRNA and protein expression is limited to the components of some molecular machines, such as the ribosome, cell adhesion complexes and the TCP-1 chaperonin involved in protein folding. Conclusions: The dynamic regulation of the transcriptome and proteome in mammalian cells in response to an acute mitogenic stimulus appears largely independent with very little

  7. Clustering effects in ionic polymers: Molecular dynamics simulations

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

    Agrawal, Anupriya; Perahia, Dvora; Grest, Gary S.

    2015-08-18

    Ionic clusters control the structure, dynamics, and transport in soft matter. Incorporating a small fraction of ionizable groups in polymers substantially reduces the mobility of the macromolecules in melts. Furthermore, these ionic groups often associate into random clusters in melts, where the distribution and morphology of the clusters impact the transport in these materials. Here, using molecular dynamic simulations we demonstrate a clear correlation between cluster size and morphology with the polymer mobility in melts of sulfonated polystyrene. We show that in low dielectric media ladderlike clusters that are lower in energy compared with spherical assemblies are formed. Reducing themore » electrostatic interactions by enhancing the dielectric constant leads to morphological transformation from ladderlike clusters to globular assemblies. Finally, decrease in electrostatic interaction significantly enhances the mobility of the polymer.« less

  8. Experimental nanocalorimetry of protonated and deprotonated water clusters

    SciTech Connect (OSTI)

    Boulon, Julien; Braud, Isabelle; Zamith, Sébastien; Labastie, Pierre; L’Hermite, Jean-Marc

    2014-04-28

    An experimental nanocalorimetric study of mass selected protonated (H{sub 2}O){sub n}H{sup +} and deprotonated (H{sub 2}O){sub n−1}OH{sup −} water clusters is reported in the size range n = 20–118. Water cluster's heat capacities exhibit a change of slope at size dependent temperatures varying from 90 to 140 K, which is ascribed to phase or structural transition. For both anionic and cationic species, these transition temperatures strongly vary at small sizes, with higher amplitude for protonated than for deprotonated clusters, and change more smoothly above roughly n ≈ 35. There is a correlation between bonding energies and transition temperatures, which is split in two components for protonated clusters while only one component is observed for deprotonated clusters. These features are tentatively interpreted in terms of structural properties of water clusters.

  9. Clustering effects in ionic polymers: Molecular dynamics simulations

    SciTech Connect (OSTI)

    Agrawal, Anupriya; Perahia, Dvora; Grest, Gary S.

    2015-08-18

    Ionic clusters control the structure, dynamics, and transport in soft matter. Incorporating a small fraction of ionizable groups in polymers substantially reduces the mobility of the macromolecules in melts. Furthermore, these ionic groups often associate into random clusters in melts, where the distribution and morphology of the clusters impact the transport in these materials. Here, using molecular dynamic simulations we demonstrate a clear correlation between cluster size and morphology with the polymer mobility in melts of sulfonated polystyrene. We show that in low dielectric media ladderlike clusters that are lower in energy compared with spherical assemblies are formed. Reducing the electrostatic interactions by enhancing the dielectric constant leads to morphological transformation from ladderlike clusters to globular assemblies. Finally, decrease in electrostatic interaction significantly enhances the mobility of the polymer.

  10. Ground-state structures of Hafnium clusters

    SciTech Connect (OSTI)

    Ng, Wei Chun; Yoon, Tiem Leong; Lim, Thong Leng

    2015-04-24

    Hafnium (Hf) is a very large tetra-valence d-block element which is able to form relatively long covalent bond. Researchers are interested to search for substitution to silicon in the semi-conductor industry. We attempt to obtain the ground-state structures of small Hf clusters at both empirical and density-functional theory (DFT) levels. For calculations at the empirical level, charge-optimized many-body functional potential (COMB) is used. The lowest-energy structures are obtained via a novel global-minimum search algorithm known as parallel tempering Monte-Carlo Basin-Hopping and Genetic Algorithm (PTMBHGA). The virtue of using COMB potential for Hf cluster calculation lies in the fact that by including the charge optimization at the valence shells, we can encourage the formation of proper bond hybridization, and thus getting the correct bond order. The obtained structures are further optimized using DFT to ensure a close proximity to the ground-state.

  11. Measuring Complementary Electronic Structure Properties of both Deposited and Gas Phase Clusters using STM, UPS, and PES: Size-Selected Clusters on Surfaces

    SciTech Connect (OSTI)

    Bowen, Kit H.

    2014-03-05

    In this project, we studied size-selected cluster interactions with surfaces, with other clusters on surfaces, and with external stimuli. These studies focused on mobility as a function of cluster size, surface morphologies as a function of composition and coverage, ion-induced modification and reactivity of clusters as a function of composition, the structural evolution of cluster cuboids culminating in the characterization of theoretically-predicted baby crystal clusters, and unusual fractal pattern formation due to deposition.

  12. Sandia National Labs: PCNSC: Departments: Small Science Cluster Business

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

    Office Sciences Semiconductor & Optical Sciences Energy Sciences Small Science Cluster Business Office News Partnering Research Georgia Rivera-Gronager Georgia Rivera-Gronager Manager Beverly Eppinga Beverly Eppinga Sr. Mgt. Asst. Departments Small Science Cluster Business Office The Small Science Cluster Business Office provides administrative support to the Physical, Chemical, & Nano Sciences Center's organizational operations; the Materials and Process Sciences Center's

  13. Jefferson Lab Awards Contract for Next Cluster Computer | Jefferson Lab

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

    Awards Contract for Next Cluster Computer Jefferson Lab Awards Contract for Next Cluster Computer February 8, 2007 Newport News, Va. - The U.S. Department of Energy's Thomas Jefferson National Accelerator Facility has awarded the contract for providing the components of its next major cluster computer installation to Koi Computers, a woman-owned, certified Small Disadvantaged Business located in Lombard, Ill. Koi won the $1.1 million contract with its bid to provide 432 dual processor, dual core

  14. NERSC Fields Its First Student Cluster Competition Team

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

    Fields Its First Student Cluster Competition Team NERSC Fields Its First Student Cluster Competition Team June 6, 2016 studentclusterteam Top row, left to right: Davina Ngai, Kristi Arroyo and Grace Rodriguez Gomez. Bottom row, left to right: Yong Li Dich, Ruoyun Zheng and Elizabeth Wang. Five former NERSC interns and one current intern have joined forces to participate in the Student Cluster Competition at ISC16, June 20-22 in Frankfurt, Germany, marking the first time that NERSC has fielded a

  15. Solvation Properties of Microhydrated Sulfate Anion Clusters: Insights from

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

    abInitio Calculations | Argonne Leadership Computing Facility Solvation Properties of Microhydrated Sulfate Anion Clusters: Insights from abInitio Calculations Authors: Wan, Q., Spanu, L., Galli, G. Sulfate-water clusters play an important role in environmental and industrial processes, yet open questions remain on their physical and chemical properties. We investigated the smallest hydrated sulfate anion clusters believed to have a full solvation shell, with 12 or 13 water molecules. We

  16. THE INFRARED SPECTROSCOPY OF NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON CLUSTERS

    SciTech Connect (OSTI)

    Ricca, Alessandra; Bauschlicher, Charles W. Jr.; Allamandola, Louis J. E-mail: Charles.W.Bauschlicher@nasa.gov

    2013-10-10

    The mid-infrared spectra of neutral homogeneous polycyclic aromatic hydrocarbon (PAH) clusters have been computed using density functional theory including an empirical correction for dispersion. The C-H out-of-plane bending modes are redshifted for all the clusters considered in this work. The magnitude of the redshift and the peak broadening are dependent on PAH size, shape, and on the PAH arrangement in the cluster.

  17. Structure of overheated metal clusters: MD simulation study

    SciTech Connect (OSTI)

    Vorontsov, Alexander

    2015-08-17

    The structure of overheated metal clusters appeared in condensation process was studied by computer simulation techniques. It was found that clusters with size larger than several tens of atoms have three layers: core part, intermediate dense packing layer and a gas- like shell with low density. The change of the size and structure of these layers with the variation of internal energy and the size of cluster is discussed.

  18. Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs

    Broader source: Energy.gov [DOE]

    Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs presentation at the April 2013 peer review meeting held in Denver, Colorado.

  19. Cluster Analysis-Based Approaches for Geospatiotemporal Data...

    Office of Scientific and Technical Information (OSTI)

    Cluster Analysis-Based Approaches for Geospatiotemporal Data Mining of Massive Data Sets for Identification of Forest Threats Mills, Richard T ORNL ORNL; Hoffman, Forrest M...

  20. in High Performance Computing Computer System, Cluster, and Networking...

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

    iSSH v. Auditd: Intrusion Detection in High Performance Computing Computer System, Cluster, and Networking Summer Institute David Karns, New Mexico State University Katy Protin,...

  1. Three-dimensional Modeling of Fracture Clusters in Geothermal...

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

    Reservoirs; 2010 Geothermal Technology Program Peer Review Report Three-dimensional Modeling of Fracture Clusters in Geothermal Reservoirs; 2010 Geothermal Technology Program Peer ...

  2. Optimizing Cluster Heads for Energy Efficiency in Large-Scale...

    Office of Scientific and Technical Information (OSTI)

    Optimizing Cluster Heads for Energy Efficiency in Large-Scale Heterogeneous Wireless Sensor Networks Gu, Yi; Wu, Qishi; Rao, Nageswara S. V. Hindawi Publishing Corporation None...

  3. Cluster expansion modeling and Monte Carlo simulation of alnico...

    Office of Scientific and Technical Information (OSTI)

    Accepted Manuscript: Cluster expansion modeling and Monte Carlo simulation of alnico 5-7 permanent magnets This content will become publicly available on March 5, 2016 Prev Next...

  4. Sequential desorption energy of hydrogen from nickel clusters

    SciTech Connect (OSTI)

    Deepika,; Kumar, Rakesh; R, Kamal Raj.; Kumar, T. J. Dhilip

    2015-06-24

    We report reversible Hydrogen adsorption on Nickel clusters, which act as a catalyst for solid state storage of Hydrogen on a substrate. First-principles technique is employed to investigate the maximum number of chemically adsorbed Hydrogen molecules on Nickel cluster. We observe a maximum of four Hydrogen molecules adsorbed per Nickel atom, but the average Hydrogen molecules adsorbed per Nickel atom decrease with cluster size. The dissociative chemisorption energy per Hydrogen molecule and sequential desorption energy per Hydrogen atom on Nickel cluster is found to decrease with number of adsorbed Hydrogen molecules, which on optimization may help in economical storage and regeneration of Hydrogen as a clean energy carrier.

  5. Optimizing Cluster Heads for Energy Efficiency in Large-Scale...

    Office of Scientific and Technical Information (OSTI)

    clustering is generally considered as an efficient and scalable way to facilitate the management and operation of such large-scale networks and minimize the total energy...

  6. Analysis of a Cluster Strategy for Near Term Hydrogen Infrastructure...

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

    Analysis of a Cluster Strategy for Near Term Hydrogen Infrastructure Rollout in Southern California Presentation at the Renewable Hydrogen Workshop, Nov. 16, 2009, in Palm Springs, ...

  7. High Temperature Membrane with HUmidification-Independent Cluster...

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

    High Temperature Membrane with HUmidification-Independent Cluster Structure A presentation ... More Documents & Publications High Temperature Membrane Working Group New Proton ...

  8. Ab initio calculations in three-body cluster systems (Journal...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; CLUSTER MODEL; GROUND STATES; GROUP THEORY; HELIUM 4; HELIUM 6; NEUTRONS; NUCLEAR STRUCTURE; RESONATING-GROUP ...

  9. Gate-tunable exchange coupling between cobalt clusters on graphene...

    Office of Scientific and Technical Information (OSTI)

    DOE PAGES Search Results Publisher's Accepted Manuscript: Gate-tunable exchange coupling between cobalt clusters on graphene Title: Gate-tunable exchange coupling between cobalt ...

  10. Backups Using Storage Clusters! Joshua T. A. Davies ...

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

    Cindy Valdez, Timothy Hemphill (DCS-CSD) LA-UR-14-26017 Overview * The Project * The Cluster * Software * Issues * Conclusions * Future Work http:www.dataprotection.comimages...

  11. A consistent approach to falsifying ?CDM with rare galaxy clusters

    SciTech Connect (OSTI)

    Harrison, Ian; Hotchkiss, Shaun E-mail: shaun.hotchkiss@helsinki.fi

    2013-07-01

    We consider methods with which to answer the question ''is any observed galaxy cluster too unusual for ?CDM?'' After emphasising that many previous attempts to answer this question will overestimate the confidence level at which ?CDM can be ruled out, we outline a consistent approach to these rare clusters, which allows the question to be answered. We define three statistical measures, each of which are sensitive to changes in cluster populations arising from different modifications to the cosmological model. We also use these properties to define the ''equivalent mass at redshift zero'' for a cluster the mass of an equally unusual cluster today. This quantity is independent of the observational survey in which the cluster was found, which makes it an ideal proxy for ranking the relative unusualness of clusters detected by different surveys. These methods are then used on a comprehensive sample of observed galaxy clusters and we confirm that all are less than 2? deviations from the ?CDM expectation. Whereas we have only applied our method to galaxy clusters, it is applicable to any isolated, collapsed, halo. As motivation for future surveys, we also calculate where in the mass redshift plane the rarest halo is most likely to be found, giving information as to which objects might be the most fruitful in the search for new physics.

  12. Supercomputing on a Shoestring: Cluster Computers at JLab | Jefferson...

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

    which describe the distribution of electric charge and current inside the nucleon. Apple To calculate the solution to a science problem, a cluster computer slices space up...

  13. Cluster-based architecture for fault-tolerant quantum computation...

    Office of Scientific and Technical Information (OSTI)

    In this cluster-based architecture, concatenated computation is implemented in a quite different way from the usual circuit-based architecture where physical gates are recursively ...

  14. Using Cluster Road Mapping to Determine Strategic Clean Energy Direction

    Office of Energy Efficiency and Renewable Energy (EERE)

    This document contains the transcript for the Using Cluster Roadmapping to Determine Your Strategic Clean Energy Direction webinar held on May 16, 2013.

  15. T-1 Training Area

    SciTech Connect (OSTI)

    2014-11-07

    Another valuable homeland security asset at the NNSS is the T-1 training area, which covers more than 10 acres and includes more than 20 separate training venues. Local, County, and State first responders who train here encounter a variety of realistic disaster scenarios. A crashed 737 airliner lying in pieces across the desert, a helicopter and other small aircraft, trucks, buses, and derailed train cars are all part of the mock incident scene. After formal classroom education, first responders are trained to take immediate decisive action to prevent or mitigate the use of radiological or nuclear devices by terrorists. The Counterterrorism Operations Support Center for Radiological Nuclear Training conducts the courses and exercises providing first responders from across the nation with the tools they need to protect their communities. All of these elements provide a training experience that cannot be duplicated anywhere else in the country.

  16. T-1 Training Area

    ScienceCinema (OSTI)

    None

    2015-01-09

    Another valuable homeland security asset at the NNSS is the T-1 training area, which covers more than 10 acres and includes more than 20 separate training venues. Local, County, and State first responders who train here encounter a variety of realistic disaster scenarios. A crashed 737 airliner lying in pieces across the desert, a helicopter and other small aircraft, trucks, buses, and derailed train cars are all part of the mock incident scene. After formal classroom education, first responders are trained to take immediate decisive action to prevent or mitigate the use of radiological or nuclear devices by terrorists. The Counterterrorism Operations Support Center for Radiological Nuclear Training conducts the courses and exercises providing first responders from across the nation with the tools they need to protect their communities. All of these elements provide a training experience that cannot be duplicated anywhere else in the country.

  17. Cluster candidates around low-power radio galaxies at z ? 1-2 in cosmos

    SciTech Connect (OSTI)

    Castignani, G.; Celotti, A.; De Zotti, G.; Chiaberge, M.; Norman, C.

    2014-09-10

    We search for high-redshift (z ?1-2) galaxy clusters using low power radio galaxies (FR I) as beacons and our newly developed Poisson probability method based on photometric redshift information and galaxy number counts. We use a sample of 32 FR Is within the Cosmic Evolution Survey (COSMOS) field from the Chiaberge et al. catalog. We derive a reliable subsample of 21 bona fide low luminosity radio galaxies (LLRGs) and a subsample of 11 high luminosity radio galaxies (HLRGs), on the basis of photometric redshift information and NRAO VLA Sky Survey radio fluxes. The LLRGs are selected to have 1.4 GHz rest frame luminosities lower than the fiducial FR I/FR II divide. This also allows us to estimate the comoving space density of sources with L {sub 1.4} ? 10{sup 32.3} erg s{sup 1} Hz{sup 1} at z ? 1.1, which strengthens the case for a strong cosmological evolution of these sources. In the fields of the LLRGs and HLRGs we find evidence that 14 and 8 of them reside in rich groups or galaxy clusters, respectively. Thus, overdensities are found around ?70% of the FR Is, independently of the considered subsample. This rate is in agreement with the fraction found for low redshift FR Is and it is significantly higher than that for FR IIs at all redshifts. Although our method is primarily introduced for the COSMOS survey, it may be applied to both present and future wide field surveys such as Sloan Digital Sky Survey Stripe 82, LSST, and Euclid. Furthermore, cluster candidates found with our method are excellent targets for next generation space telescopes such as James Webb Space Telescope.

  18. Radiation detection method and system using the sequential probability ratio test

    DOE Patents [OSTI]

    Nelson, Karl E.; Valentine, John D.; Beauchamp, Brock R.

    2007-07-17

    A method and system using the Sequential Probability Ratio Test to enhance the detection of an elevated level of radiation, by determining whether a set of observations are consistent with a specified model within a given bounds of statistical significance. In particular, the SPRT is used in the present invention to maximize the range of detection, by providing processing mechanisms for estimating the dynamic background radiation, adjusting the models to reflect the amount of background knowledge at the current point in time, analyzing the current sample using the models to determine statistical significance, and determining when the sample has returned to the expected background conditions.

  19. Use of the AIC with the EM algorithm: A demonstration of a probability model selection technique

    SciTech Connect (OSTI)

    Glosup, J.G.; Axelrod M.C.

    1994-11-15

    The problem of discriminating between two potential probability models, a Gaussian distribution and a mixture of Gaussian distributions, is considered. The focus of our interest is a case where the models are potentially non-nested and the parameters of the mixture model are estimated through the EM algorithm. The AIC, which is frequently used as a criterion for discriminating between non-nested models, is modified to work with the EM algorithm and is shown to provide a model selection tool for this situation. A particular problem involving an infinite mixture distribution known as Middleton`s Class A model is used to demonstrate the effectiveness and limitations of this method.

  20. Dependence in probabilistic modeling, Dempster-Shafer theory, and probability bounds analysis.

    SciTech Connect (OSTI)

    Oberkampf, William Louis; Tucker, W. Troy; Zhang, Jianzhong; Ginzburg, Lev; Berleant, Daniel J.; Ferson, Scott; Hajagos, Janos; Nelsen, Roger B.

    2004-10-01

    This report summarizes methods to incorporate information (or lack of information) about inter-variable dependence into risk assessments that use Dempster-Shafer theory or probability bounds analysis to address epistemic and aleatory uncertainty. The report reviews techniques for simulating correlated variates for a given correlation measure and dependence model, computation of bounds on distribution functions under a specified dependence model, formulation of parametric and empirical dependence models, and bounding approaches that can be used when information about the intervariable dependence is incomplete. The report also reviews several of the most pervasive and dangerous myths among risk analysts about dependence in probabilistic models.

  1. Characterization of the Praesepe star cluster by photometry and proper motions with 2MASS, PPMXL, and Pan-STARRS

    SciTech Connect (OSTI)

    Wang, P. F.; Chen, W. P.; Lin, C. C.; Huang, C. K.; Panwar, N.; Lee, C. H.; Pandey, A. K.; Tsai, M. F.; Tang, C.-H.; Goldman, B.; Burgett, W. S.; Chambers, K. C.; Flewelling, H.; Heasley, J. N.; Hodapp, K. W.; Huber, M. E.; Jedicke, R.; Kaiser, N.; Draper, P. W.; Grav, T.; and others

    2014-03-20

    Membership identification is the first step in determining the properties of a star cluster. Low-mass members in particular could be used to trace the dynamical history, such as mass segregation, stellar evaporation, or tidal stripping, of a star cluster in its Galactic environment. We identified member candidates of the intermediate-age Praesepe cluster (M44) with stellar masses ?0.11-2.4 M {sub ?}, using Panoramic Survey Telescope And Rapid Response System and Two Micron All Sky Survey photometry, and PPMXL proper motions. Within a sky area of 3 radius, 1040 candidates are identified, of which 96 are new inclusions. Using the same set of selection criteria on field stars, an estimated false positive rate of 16% was determined, suggesting that 872 of the candidates are true members. This most complete and reliable membership list allows us to favor the BT-Settl model over other stellar models. The cluster shows a distinct binary track above the main sequence, with a binary frequency of 20%-40%, and a high occurrence rate of similar mass pairs. The mass function is consistent with that of the disk population but shows a deficit of members below 0.3 solar masses. A clear mass segregation is evidenced, with the lowest-mass members in our sample being evaporated from this disintegrating cluster.

  2. The era of star formation in galaxy clusters

    SciTech Connect (OSTI)

    Brodwin, M.; Stanford, S. A.; Gonzalez, Anthony H.; Mancone, C. L.; Gettings, D. P.; Zeimann, G. R.; Snyder, G. F.; Ashby, M. L. N.; Pope, A.; Alberts, S.; Eisenhardt, P. R.; Stern, D.; Moustakas, L. A.; Brown, M. J. I.; Chary, R.-R.; Dey, Arjun; Galametz, A.; Jannuzi, B. T.; Miller, E. D.; Moustakas, J.

    2013-12-20

    We analyze the star formation properties of 16 infrared-selected, spectroscopically confirmed galaxy clusters at 1 < z < 1.5 from the Spitzer/IRAC Shallow Cluster Survey (ISCS). We present new spectroscopic confirmation for six of these high-redshift clusters, five of which are at z > 1.35. Using infrared luminosities measured with deep Spitzer/Multiband Imaging Photometer for Spitzer observations at 24 μm, along with robust optical + IRAC photometric redshifts and spectral-energy-distribution-fitted stellar masses, we present the dust-obscured star-forming fractions, star formation rates, and specific star formation rates in these clusters as functions of redshift and projected clustercentric radius. We find that z ∼ 1.4 represents a transition redshift for the ISCS sample, with clear evidence of an unquenched era of cluster star formation at earlier times. Beyond this redshift, the fraction of star-forming cluster members increases monotonically toward the cluster centers. Indeed, the specific star formation rate in the cores of these distant clusters is consistent with field values at similar redshifts, indicating that at z > 1.4 environment-dependent quenching had not yet been established in ISCS clusters. By combining these observations with complementary studies showing a rapid increase in the active galactic nucleus (AGN) fraction, a stochastic star formation history, and a major merging episode at the same epoch in this cluster sample, we suggest that the starburst activity is likely merger-driven and that the subsequent quenching is due to feedback from merger-fueled AGNs. The totality of the evidence suggests we are witnessing the final quenching period that brings an end to the era of star formation in galaxy clusters and initiates the era of passive evolution.

  3. NCS area of applicability determination for AVLIS

    SciTech Connect (OSTI)

    Gross, C.; Koopman, R.P.

    1999-07-01

    The authors present a method for examining congruence between the processes that make up an AVLIS enrichment plant and the benchmark critical experiments that are used to establish the bias and validate the codes used for nuclear criticality safety (NCS) calculations of those processes. A measure of the validity of the process of selecting critical experiments that are similar in nature to processes found in the plant is presented. The probability of fission depends primarily on neutron energy and the interaction cross sections of the materials in the process. The physics of fission has led one to consider the energy of neutrons causing fission to be the fundamental parameter for examining the area of applicability. Benchmark experiments are chosen to cover the material compositions, geometric arrangements, neutron energy spectra, and other parameters such as material heterogeneity, neutron leakage or reflection, interaction, and absorption in special materials. These parameters influence the process by affecting the number of neutrons available to cause fission at any given energy. The neutron energy distribution is established primarily as a result of the energy-dependent cross sections for the materials that are present. Thus, the energy of neutrons causing fission is the fundamental parameter needed for examining the effects of other parameters within the area of applicability.

  4. Water Clustering on Nanostructured Iron Oxide Films

    SciTech Connect (OSTI)

    Merte, L. R.; Bechstein, Ralf; Peng, Guowen; Rieboldt, Felix; Farberow, Carrie A.; Zeuthen, Helene; Knudsen, Jan; Laegsgaard, E.; Wendt, Stefen; Mavrikakis, Manos; Besenbacher, Fleming

    2014-06-30

    The adhesion of water to solid surfaces is characterized by the tendency to balance competing moleculemolecule and moleculesurface interactions. Hydroxyl groups form strong hydrogen bonds to water molecules and are known to substantially influence the wetting behaviour of oxide surfaces, but it is not well-understood how these hydroxyl groups and their distribution on a surface affect the molecular-scale structure at the interface. Here we report a study of water clustering on a moire-structured iron oxide thin film with a controlled density of hydroxyl groups. While large amorphous monolayer islands form on the are film, the hydroxylated iron oxide film acts as a hydrophilic nanotemplate, causing the formation of a regular array of ice-like hexameric nanoclusters. The formation of this ordered phase is localized at the nanometre scale; with increasing water coverage, ordered and amorphous water are found to coexist at adjacent hydroxylated and hydroxyl-free domains of the moire structure.

  5. Anion photoelectron spectroscopy of radicals and clusters

    SciTech Connect (OSTI)

    Travis, Taylor R.

    1999-12-16

    Anion photoelectron spectroscopy is used to study free radicals and clusters. The low-lying {sup 2}{Sigma} and {sup 2}{Pi} states of C{sub 2n}H (n = 1--4) have been studied. The anion photoelectron spectra yielded electron affinities, term values, and vibrational frequencies for these combustion and astrophysically relevant species. Photoelectron angular distributions allowed the author to correctly assign the electronic symmetry of the ground and first excited states and to assess the degree of vibronic coupling in C{sub 2}H and C{sub 4}H. Other radicals studied include NCN and I{sub 3}. The author was able to observe the low-lying singlet and triplet states of NCN for the first time. Measurement of the electron affinity of I{sub 3} revealed that it has a bound ground state and attachment of an argon atom to this moiety enabled him to resolve the symmetric stretching progression.

  6. Perspective: Water cluster mediated atmospheric chemistry

    SciTech Connect (OSTI)

    Vaida, Veronica

    2011-07-14

    The importance of water in atmospheric and environmental chemistry initiated recent studies with results documenting catalysis, suppression and anti-catalysis of thermal and photochemical reactions due to hydrogen bonding of reagents with water. Water, even one water molecule in binary complexes, has been shown by quantum chemistry to stabilize the transition state and lower its energy. However, new results underscore the need to evaluate the relative competing rates between reaction and dissipation to elucidate the role of water in chemistry. Water clusters have been used successfully as models for reactions in gas-phase, in aqueous condensed phases and at aqueous surfaces. Opportunities for experimental and theoretical chemical physics to make fundamental new discoveries abound. Work in this field is timely given the importance of water in atmospheric and environmental chemistry.

  7. Clustering of cycloidal wave energy converters

    DOE Patents [OSTI]

    Siegel, Stefan G.

    2016-03-29

    A wave energy conversion system uses a pair of wave energy converters (WECs) on respective active mountings on a floating platform, so that the separation of the WECs from each other or from a central WEC can be actively adjusted according to the wavelength of incident waves. The adjustable separation facilitates operation of the system to cancel reactive forces, which may be generated during wave energy conversion. Modules on which such pairs of WECs are mounted can be assembled with one or more central WECs to form large clusters in which reactive forces and torques can be made to cancel. WECs of different sizes can be employed to facilitate cancelation of reactive forces and torques.

  8. The electron screening puzzle and nuclear clustering

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

    Spitaleri, C.; Bertulani, C. A.; Fortunato, L.; Vitturi, A.

    2016-02-12

    Accurate measurements of nuclear reactions of astrophysical interest within, or close to, the Gamow peak show evidence of an unexpected effect attributed to the presence of atomic electrons in the target. The experiments need to include an effective "screening" potential to explain the enhancement of the cross sections at the lowest measurable energies. Despite various theoretical studies conducted over the past 20 years and numerous experimental measurements, a theory has not yet been found that can explain the cause of the exceedingly high values of the screening potential needed to explain the data. Furthermore, in this letter we show thatmore » instead of an atomic physics solution of the "electron screening puzzle", the reason for the large screening potential values is in fact due to clusterization effects in nuclear reactions, in particular for reaction involving light nuclei.« less

  9. Probability density function characterization for aggregated large-scale wind power based on Weibull mixtures

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

    Gomez-Lazaro, Emilio; Bueso, Maria C.; Kessler, Mathieu; Martin-Martinez, Sergio; Zhang, Jie; Hodge, Bri -Mathias; Molina-Garcia, Angel

    2016-02-02

    Here, the Weibull probability distribution has been widely applied to characterize wind speeds for wind energy resources. Wind power generation modeling is different, however, due in particular to power curve limitations, wind turbine control methods, and transmission system operation requirements. These differences are even greater for aggregated wind power generation in power systems with high wind penetration. Consequently, models based on one-Weibull component can provide poor characterizations for aggregated wind power generation. With this aim, the present paper focuses on discussing Weibull mixtures to characterize the probability density function (PDF) for aggregated wind power generation. PDFs of wind power datamore » are firstly classified attending to hourly and seasonal patterns. The selection of the number of components in the mixture is analyzed through two well-known different criteria: the Akaike information criterion (AIC) and the Bayesian information criterion (BIC). Finally, the optimal number of Weibull components for maximum likelihood is explored for the defined patterns, including the estimated weight, scale, and shape parameters. Results show that multi-Weibull models are more suitable to characterize aggregated wind power data due to the impact of distributed generation, variety of wind speed values and wind power curtailment.« less

  10. Modeling Stress Strain Relationships and Predicting Failure Probabilities For Graphite Core Components

    SciTech Connect (OSTI)

    Duffy, Stephen

    2013-09-09

    This project will implement inelastic constitutive models that will yield the requisite stress-strain information necessary for graphite component design. Accurate knowledge of stress states (both elastic and inelastic) is required to assess how close a nuclear core component is to failure. Strain states are needed to assess deformations in order to ascertain serviceability issues relating to failure, e.g., whether too much shrinkage has taken place for the core to function properly. Failure probabilities, as opposed to safety factors, are required in order to capture the bariability in failure strength in tensile regimes. The current stress state is used to predict the probability of failure. Stochastic failure models will be developed that can accommodate possible material anisotropy. This work will also model material damage (i.e., degradation of mechanical properties) due to radiation exposure. The team will design tools for components fabricated from nuclear graphite. These tools must readily interact with finite element software--in particular, COMSOL, the software algorithm currently being utilized by the Idaho National Laboratory. For the eleastic response of graphite, the team will adopt anisotropic stress-strain relationships available in COMSO. Data from the literature will be utilized to characterize the appropriate elastic material constants.

  11. Strong lensing probability in TeVeS (tensor-vector-scalar) theory

    SciTech Connect (OSTI)

    Chen Daming

    2008-01-15

    We recalculate the strong lensing probability as a function of the image separation in TeVeS (tensor-vector-scalar) cosmology, which is a relativistic version of MOND (MOdified Newtonian Dynamics). The lens is modeled by the Hernquist profile. We assume an open cosmology with {Omega}{sub b} = 0.04 and {Omega}{sub {Lambda}} = 0.5 and three different kinds of interpolating functions. Two different galaxy stellar mass functions (GSMF) are adopted: PHJ (Panter, Heavens and Jimenez 2004 Mon. Not. R. Astron. Soc. 355 764) determined from SDSS data release 1 and Fontana (Fontana et al 2006 Astron. Astrophys. 459 745) from GOODS-MUSIC catalog. We compare our results with both the predicted probabilities for lenses from singular isothermal sphere galaxy halos in LCDM (Lambda cold dark matter) with a Schechter-fit velocity function, and the observational results for the well defined combined sample of the Cosmic Lens All-Sky Survey (CLASS) and Jodrell Bank/Very Large Array Astrometric Survey (JVAS). It turns out that the interpolating function {mu}(x) = x/(1+x) combined with Fontana GSMF matches the results from CLASS/JVAS quite well.

  12. Determination of laser damage initiation probability and growth on fused silica scratches

    SciTech Connect (OSTI)

    Norton, M A; Carr, C W; Cross, D A; Negres, R A; Bude, J D; Steele, W A; Monticelli, M V; Suratwala, T I

    2010-10-26

    Current methods for the manufacture of optical components inevitably leaves a variety of sub-surface imperfections including scratches of varying lengths and widths on even the finest finishes. It has recently been determined that these finishing imperfections are responsible for the majority of laser-induced damage for fluences typically used in ICF class lasers. We have developed methods of engineering subscale parts with a distribution of scratches mimicking those found on full scale fused silica parts. This much higher density of scratches provides a platform to measure low damage initiation probabilities sufficient to describe damage on large scale optics. In this work, damage probability per unit scratch length was characterized as a function of initial scratch width and post fabrication processing including acid-based etch mitigation processes. The susceptibility of damage initiation density along scratches was found to be strongly affected by the post etching material removal and initial scratch width. We have developed an automated processing procedure to document the damage initiations per width and per length of theses scratches. We show here how these tools can be employed to provide predictions of the performance of full size optics in laser systems operating at 351 nm. In addition we use these tools to measure the growth rate of a damage site initiated along a scratch and compare this to the growth measured on an isolated damage site.

  13. Understanding the distinctively skewed and heavy tailed character of atmospheric and oceanic probability distributions

    SciTech Connect (OSTI)

    Sardeshmukh, Prashant D.

    2015-03-15

    The probability distributions of large-scale atmospheric and oceanic variables are generally skewed and heavy-tailed. We argue that their distinctive departures from Gaussianity arise fundamentally from the fact that in a quadratically nonlinear system with a quadratic invariant, the coupling coefficients between system components are not constant but depend linearly on the system state in a distinctive way. In particular, the skewness arises from a tendency of the system trajectory to linger near states of weak coupling. We show that the salient features of the observed non-Gaussianity can be captured in the simplest such nonlinear 2-component system. If the system is stochastically forced and linearly damped, with one component damped much more strongly than the other, then the strongly damped fast component becomes effectively decoupled from the weakly damped slow component, and its impact on the slow component can be approximated as a stochastic noise forcing plus an augmented nonlinear damping. In the limit of large time-scale separation, the nonlinear augmentation of the damping becomes small, and the noise forcing can be approximated as an additive noise plus a correlated additive and multiplicative noise (CAM noise) forcing. Much of the diversity of observed large-scale atmospheric and oceanic probability distributions can be interpreted in this minimal framework.

  14. Measuring and Modeling Fault Density for Plume-Fault Encounter Probability Estimation

    SciTech Connect (OSTI)

    Jordan, P.D.; Oldenburg, C.M.; Nicot, J.-P.

    2011-05-15

    Emission of carbon dioxide from fossil-fueled power generation stations contributes to global climate change. Storage of this carbon dioxide within the pores of geologic strata (geologic carbon storage) is one approach to mitigating the climate change that would otherwise occur. The large storage volume needed for this mitigation requires injection into brine-filled pore space in reservoir strata overlain by cap rocks. One of the main concerns of storage in such rocks is leakage via faults. In the early stages of site selection, site-specific fault coverages are often not available. This necessitates a method for using available fault data to develop an estimate of the likelihood of injected carbon dioxide encountering and migrating up a fault, primarily due to buoyancy. Fault population statistics provide one of the main inputs to calculate the encounter probability. Previous fault population statistics work is shown to be applicable to areal fault density statistics. This result is applied to a case study in the southern portion of the San Joaquin Basin with the result that the probability of a carbon dioxide plume from a previously planned injection had a 3% chance of encountering a fully seal offsetting fault.

  15. What is the probability that direct detection experiments have observed dark matter?

    SciTech Connect (OSTI)

    Bozorgnia, Nassim; Schwetz, Thomas E-mail: schwetz@fysik.su.se

    2014-12-01

    In Dark Matter direct detection we are facing the situation of some experiments reporting positive signals which are in conflict with limits from other experiments. Such conclusions are subject to large uncertainties introduced by the poorly known local Dark Matter distribution. We present a method to calculate an upper bound on the joint probability of obtaining the outcome of two potentially conflicting experiments under the assumption that the Dark Matter hypothesis is correct, but completely independent of assumptions about the Dark Matter distribution. In this way we can quantify the compatibility of two experiments in an astrophysics independent way. We illustrate our method by testing the compatibility of the hints reported by DAMA and CDMS-Si with the limits from the LUX and SuperCDMS experiments. The method does not require Monte Carlo simulations but is mostly based on using Poisson statistics. In order to deal with signals of few events we introduce the so-called ''signal length'' to take into account energy information. The signal length method provides a simple way to calculate the probability to obtain a given experimental outcome under a specified Dark Matter and background hypothesis.

  16. Accelerating Subsurface Transport Simulation on Heterogeneous Clusters

    SciTech Connect (OSTI)

    Villa, Oreste; Gawande, Nitin A.; Tumeo, Antonino

    2013-09-23

    Reactive transport numerical models simulate chemical and microbiological reactions that occur along a flowpath. These models have to compute reactions for a large number of locations. They solve the set of ordinary differential equations (ODEs) that describes the reaction for each location through the Newton-Raphson technique. This technique involves computing a Jacobian matrix and a residual vector for each set of equation, and then solving iteratively the linearized system by performing Gaussian Elimination and LU decomposition until convergence. STOMP, a well known subsurface flow simulation tool, employs matrices with sizes in the order of 100x100 elements and, for numerical accuracy, LU factorization with full pivoting instead of the faster partial pivoting. Modern high performance computing systems are heterogeneous machines whose nodes integrate both CPUs and GPUs, exposing unprecedented amounts of parallelism. To exploit all their computational power, applications must use both the types of processing elements. For the case of subsurface flow simulation, this mainly requires implementing efficient batched LU-based solvers and identifying efficient solutions for enabling load balancing among the different processors of the system. In this paper we discuss two approaches that allows scaling STOMP's performance on heterogeneous clusters. We initially identify the challenges in implementing batched LU-based solvers for small matrices on GPUs, and propose an implementation that fulfills STOMP's requirements. We compare this implementation to other existing solutions. Then, we combine the batched GPU solver with an OpenMP-based CPU solver, and present an adaptive load balancer that dynamically distributes the linear systems to solve between the two components inside a node. We show how these approaches, integrated into the full application, provide speed ups from 6 to 7 times on large problems, executed on up to 16 nodes of a cluster with two AMD Opteron 6272

  17. AREA RADIATION MONITOR

    DOE Patents [OSTI]

    Manning, F.W.; Groothuis, S.E.; Lykins, J.H.; Papke, D.M.

    1962-06-12

    S>An improved area radiation dose monitor is designed which is adapted to compensate continuously for background radiation below a threshold dose rate and to give warning when the dose integral of the dose rate of an above-threshold radiation excursion exceeds a selected value. This is accomplished by providing means for continuously charging an ionization chamber. The chamber provides a first current proportional to the incident radiation dose rate. Means are provided for generating a second current including means for nulling out the first current with the second current at all values of the first current corresponding to dose rates below a selected threshold dose rate value. The second current has a maximum value corresponding to that of the first current at the threshold dose rate. The excess of the first current over the second current, which occurs above the threshold, is integrated and an alarm is given at a selected integrated value of the excess corresponding to a selected radiation dose. (AEC)

  18. SSL Demonstration: Area Lighting Yuma Sector Border Patrol Area...

    Energy Savers [EERE]

    DEMONSTRATION: Area Lighting Yuma Sector Border Patrol Area, AZ A unique GATEWAY evaluation on a stretch of border between the U.S. and Mexico looks at how high-flux LED lighting ...

  19. A Distributed Flocking Approach for Information Stream Clustering Analysis

    SciTech Connect (OSTI)

    Cui, Xiaohui; Potok, Thomas E

    2006-01-01

    Intelligence analysts are currently overwhelmed with the amount of information streams generated everyday. There is a lack of comprehensive tool that can real-time analyze the information streams. Document clustering analysis plays an important role in improving the accuracy of information retrieval. However, most clustering technologies can only be applied for analyzing the static document collection because they normally require a large amount of computation resource and long time to get accurate result. It is very difficult to cluster a dynamic changed text information streams on an individual computer. Our early research has resulted in a dynamic reactive flock clustering algorithm which can continually refine the clustering result and quickly react to the change of document contents. This character makes the algorithm suitable for cluster analyzing dynamic changed document information, such as text information stream. Because of the decentralized character of this algorithm, a distributed approach is a very natural way to increase the clustering speed of the algorithm. In this paper, we present a distributed multi-agent flocking approach for the text information stream clustering and discuss the decentralized architectures and communication schemes for load balance and status information synchronization in this approach.

  20. Hierarchical clustering using correlation metric and spatial continuity constraint

    DOE Patents [OSTI]

    Stork, Christopher L.; Brewer, Luke N.

    2012-10-02

    Large data sets are analyzed by hierarchical clustering using correlation as a similarity measure. This provides results that are superior to those obtained using a Euclidean distance similarity measure. A spatial continuity constraint may be applied in hierarchical clustering analysis of images.

  1. Silica-Supported Tantalum Clusters: Catalyst for Alkane Conversion

    SciTech Connect (OSTI)

    Nemana ,S.; Gates, B.

    2006-01-01

    Silica-supported tantalum clusters (on average, approximately tritantalum) were formed by the treatment, in either H{sub 2} or ethane, of adsorbed Ta(CH{sub 2}Ph){sub 5}; the supported catalyst is active for ethane conversion to methane and propane at 523 K, with the used catalyst containing clusters of the same average nuclearity as the precursor.

  2. The evolutionary tracks of young massive star clusters

    SciTech Connect (OSTI)

    Pfalzner, S.; Steinhausen, M.; Vincke, K.; Menten, K.; Parmentier, G.

    2014-10-20

    Stars mostly form in groups consisting of a few dozen to several ten thousand members. For 30 years, theoretical models have provided a basic concept of how such star clusters form and develop: they originate from the gas and dust of collapsing molecular clouds. The conversion from gas to stars being incomplete, the leftover gas is expelled, leading to cluster expansion and stars becoming unbound. Observationally, a direct confirmation of this process has proved elusive, which is attributed to the diversity of the properties of forming clusters. Here we take into account that the true cluster masses and sizes are masked, initially by the surface density of the background and later by the still present unbound stars. Based on the recent observational finding that in a given star-forming region the star formation efficiency depends on the local density of the gas, we use an analytical approach combined with N-body simulations to reveal evolutionary tracks for young massive clusters covering the first 10 Myr. Just like the Hertzsprung-Russell diagram is a measure for the evolution of stars, these tracks provide equivalent information for clusters. Like stars, massive clusters form and develop faster than their lower-mass counterparts, explaining why so few massive cluster progenitors are found.

  3. Low work function, stable compound clusters and generation process

    DOE Patents [OSTI]

    Dinh, Long N.; Balooch, Mehdi; Schildbach, Marcus A.; Hamza, Alex V.; McLean, II, William

    2000-01-01

    Low work function, stable compound clusters are generated by co-evaporation of a solid semiconductor (i.e., Si) and alkali metal (i.e., Cs) elements in an oxygen environment. The compound clusters are easily patterned during deposition on substrate surfaces using a conventional photo-resist technique. The cluster size distribution is narrow, with a peak range of angstroms to nanometers depending on the oxygen pressure and the Si source temperature. Tests have shown that compound clusters when deposited on a carbon substrate contain the desired low work function property and are stable up to 600.degree. C. Using the patterned cluster containing plate as a cathode baseplate and a faceplate covered with phosphor as an anode, one can apply a positive bias to the faceplate to easily extract electrons and obtain illumination.

  4. Structure based alignment and clustering of proteins (STRALCP)

    DOE Patents [OSTI]

    Zemla, Adam T.; Zhou, Carol E.; Smith, Jason R.; Lam, Marisa W.

    2013-06-18

    Disclosed are computational methods of clustering a set of protein structures based on local and pair-wise global similarity values. Pair-wise local and global similarity values are generated based on pair-wise structural alignments for each protein in the set of protein structures. Initially, the protein structures are clustered based on pair-wise local similarity values. The protein structures are then clustered based on pair-wise global similarity values. For each given cluster both a representative structure and spans of conserved residues are identified. The representative protein structure is used to assign newly-solved protein structures to a group. The spans are used to characterize conservation and assign a "structural footprint" to the cluster.

  5. Subnanometer platinum clusters highly active and selective catalysts for the oxidative dehydrogenation of propane.

    SciTech Connect (OSTI)

    Vajda, S; Pellin, M. J.; Greeley, J. P.; Marshall, C. L.; Curtiss, L. A.; Ballentine, G. A.; Elam, J. W.; Catillon-Mucherie, S.; Redfern, P. C.; Mehmood, F.; Zapol, P.; Yale Univ.

    2009-03-01

    Small clusters are known to possess reactivity not observed in their bulk analogues, which can make them attractive for catalysis. Their distinct catalytic properties are often hypothesized to result from the large fraction of under-coordinated surface atoms. Here, we show that size-preselected Pt{sub 8-10} clusters stabilized on high-surface-area supports are 40-100 times more active for the oxidative dehydrogenation of propane than previously studied platinum and vanadia catalysts, while at the same time maintaining high selectivity towards formation of propylene over by-products. Quantum chemical calculations indicate that under-coordination of the Pt atoms in the clusters is responsible for the surprisingly high reactivity compared with extended surfaces. We anticipate that these results will form the basis for development of a new class of catalysts by providing a route to bond-specific chemistry, ranging from energy-efficient and environmentally friendly synthesis strategies to the replacement of petrochemical feedstocks by abundant small alkanes.

  6. Threshold selection for classification of MR brain images by clustering method

    SciTech Connect (OSTI)

    Moldovanu, Simona; Obreja, Cristian; Moraru, Luminita

    2015-12-07

    Given a grey-intensity image, our method detects the optimal threshold for a suitable binarization of MR brain images. In MR brain image processing, the grey levels of pixels belonging to the object are not substantially different from the grey levels belonging to the background. Threshold optimization is an effective tool to separate objects from the background and further, in classification applications. This paper gives a detailed investigation on the selection of thresholds. Our method does not use the well-known method for binarization. Instead, we perform a simple threshold optimization which, in turn, will allow the best classification of the analyzed images into healthy and multiple sclerosis disease. The dissimilarity (or the distance between classes) has been established using the clustering method based on dendrograms. We tested our method using two classes of images: the first consists of 20 T2-weighted and 20 proton density PD-weighted scans from two healthy subjects and from two patients with multiple sclerosis. For each image and for each threshold, the number of the white pixels (or the area of white objects in binary image) has been determined. These pixel numbers represent the objects in clustering operation. The following optimum threshold values are obtained, T = 80 for PD images and T = 30 for T2w images. Each mentioned threshold separate clearly the clusters that belonging of the studied groups, healthy patient and multiple sclerosis disease.

  7. COMPARISONS OF COSMOLOGICAL MAGNETOHYDRODYNAMIC GALAXY CLUSTER SIMULATIONS TO RADIO OBSERVATIONS

    SciTech Connect (OSTI)

    Xu Hao; Li Hui; Collins, David C.; Govoni, Federica; Murgia, Matteo; Norman, Michael L.; Cen Renyue; Feretti, Luigina; Giovannini, Gabriele E-mail: hli@lanl.gov E-mail: mlnorman@ucsd.edu E-mail: matteo@oa-cagliari.inaf.it E-mail: lferetti@ira.inaf.it

    2012-11-01

    Radio observations of galaxy clusters show that there are {mu}G magnetic fields permeating the intracluster medium (ICM), but it is hard to accurately constrain the strength and structure of the magnetic fields without the help of advanced computer simulations. We present qualitative comparisons of synthetic Very Large Array observations of simulated galaxy clusters to radio observations of Faraday rotation measure (RM) and radio halos. The cluster formation is modeled using adaptive mesh refinement magnetohydrodynamic simulations with the assumption that the initial magnetic fields are injected into the ICM by active galactic nuclei (AGNs) at high redshift. In addition to simulated clusters in Xu et al., we present a new simulation with magnetic field injections from multiple AGNs. We find that the cluster with multiple injection sources is magnetized to a similar level as in previous simulations with a single AGN. The RM profiles from simulated clusters, both |RM| and the dispersion of RM ({sigma}{sub RM}), are consistent at a first order with the radial distribution from observations. The correlations between the {sigma}{sub RM} and X-ray surface brightness from simulations are in a broad agreement with the observations, although there is an indication that the simulated clusters could be slightly overdense and less magnetized with respect to those in the observed sample. In addition, the simulated radio halos agree with the observed correlations between the radio power versus the cluster X-ray luminosity and between the radio power versus the radio halo size. These studies show that the cluster-wide magnetic fields that originate from AGNs and are then amplified by the ICM turbulence match observations of magnetic fields in galaxy clusters.

  8. PREDICTING MERGER-INDUCED GAS MOTIONS IN ?CDM GALAXY CLUSTERS

    SciTech Connect (OSTI)

    Nagai, Daisuke; Lau, Erwin T.; Avestruz, Camille; Rudd, Douglas H.; Nelson, Kaylea

    2013-11-10

    In the hierarchical structure formation model, clusters of galaxies form through a sequence of mergers and continuous mass accretion, which generate significant random gas motions especially in their outskirts where material is actively accreting. Non-thermal pressure provided by the internal gas motions affects the thermodynamic structure of the X-ray emitting intracluster plasma and introduces biases in the physical interpretation of X-ray and Sunyaev-Zeldovich effect observations. However, we know very little about the nature of gas motions in galaxy clusters. The ASTRO-H X-ray mission, scheduled to launch in 2015, will have a calorimeter capable of measuring gas motions in galaxy clusters at the level of ?< 100 km s{sup 1}. In this work, we predict the level of merger-induced gas motions expected in the ?CDM model using hydrodynamical simulations of galaxy cluster formation. We show that the gas velocity dispersion is larger in more massive clusters, but exhibits a large scatter. We show that systems with large gas motions are morphologically disturbed, while early forming, relaxed groups show a smaller level of gas motions. By analyzing mock ASTRO-H observations of simulated clusters, we show that such observations can accurately measure the gas velocity dispersion out to the outskirts of nearby relaxed galaxy clusters. ASTRO-H analysis of merging clusters, on the other hand, requires multi-component spectral fitting and enables unique studies of substructures in galaxy clusters by measuring both the peculiar velocities and the velocity dispersion of gas within individual sub-clusters.

  9. The GSAM software: A global search algorithm of minima exploration for the investigation of low lying isomers of clusters

    SciTech Connect (OSTI)

    Marchal, Rémi; Carbonnière, Philippe; Pouchan, Claude

    2015-01-22

    The study of atomic clusters has become an increasingly active area of research in the recent years because of the fundamental interest in studying a completely new area that can bridge the gap between atomic and solid state physics. Due to their specific properties, such compounds are of great interest in the field of nanotechnology [1,2]. Here, we would present our GSAM algorithm based on a DFT exploration of the PES to find the low lying isomers of such compounds. This algorithm includes the generation of an intial set of structure from which the most relevant are selected. Moreover, an optimization process, called raking optimization, able to discard step by step all the non physically reasonnable configurations have been implemented to reduce the computational cost of this algorithm. Structural properties of Ga{sub n}Asm clusters will be presented as an illustration of the method.

  10. Ionization of large homogeneous and heterogeneous clusters generated in acetylene-Ar expansions: Cluster ion polymerization

    SciTech Connect (OSTI)

    Kocisek, J.; Lengyel, J.; Farnik, M.

    2013-03-28

    Pure acetylene and mixed Ar-acetylene clusters are formed in supersonic expansions of acetylene/argon mixtures and analysed using reflectron time-of-flight mass spectrometer with variable electron energy ionization source. Acetylene clusters composed of more than a hundred acetylene molecules are generated at the acetylene concentration of Almost-Equal-To 8%, while mixed species are produced at low concentrations ( Almost-Equal-To 0.7%). The electron energy dependence of the mass spectra revealed the ionization process mechanisms in clusters. The ionization above the threshold for acetylene molecule of 11.5 eV results in the main ionic fragment progression (C{sub 2}H{sub 2}){sub n}{sup +}. At the electron energies Greater-Than-Or-Slanted-Equal-To 21.5 eV above the CH+CH{sup +} dissociative ionization limit of acetylene the fragment ions nominally labelled as (C{sub 2}H{sub 2}){sub n}CH{sup +}, n Greater-Than-Or-Slanted-Equal-To 2, are observed. For n Less-Than-Or-Slanted-Equal-To 7 these fragments correspond to covalently bound ionic structures as suggested by the observed strong dehydrogenation [(C{sub 2}H{sub 2}){sub n}-k Multiplication-Sign H]{sup +} and [(C{sub 2}H{sub 2}){sub n}CH -k Multiplication-Sign H]{sup +}. The dehydrogenation is significantly reduced in the mixed clusters where evaporation of Ar instead of hydrogen can stabilize the nascent molecular ion. The C{sub 3}H{sub 3}{sup +} ion was previously assigned to originate from the benzene molecular ion; however, the low appearance energy of Almost-Equal-To 13.7 eV indicates that a less rigid covalently bound structure of C{sub 6}H{sub 6}{sup +} ion must also be formed upon the acetylene cluster electron ionization. The appearance energy of Ar{sub n}(C{sub 2}H{sub 2}){sup +} fragments above Almost-Equal-To 15.1 eV indicates that the argon ionization is the first step in the fragment ion production, and the appearance energy of Ar{sub n{>=}2}(C{sub 2}H{sub 2}){sub m{>=}2}{sup +} at Almost-Equal-To 13

  11. F Reactor Area Cleanup Complete

    Broader source: Energy.gov [DOE]

    RICHLAND, Wash. – U.S. Department of Energy (DOE) contractors have cleaned up the F Reactor Area, the first reactor area at the Hanford Site in southeastern Washington state to be fully remediated.

  12. Galaxy Clusters in the Swift/BAT era II: 10 more Clusters detected above 15 keV

    SciTech Connect (OSTI)

    Ajello, M.; Rebusco, P.; Cappelluti, N.; Reimer, O.; Boehringer, H.; La Parola, V.; Cusumano, G.; ,

    2010-10-27

    We report on the discovery of 10 additional galaxy clusters detected in the ongoing Swift/BAT all-sky survey. Among the newly BAT-discovered clusters there are: Bullet, Abell 85, Norma, and PKS 0745-19. Norma is the only cluster, among those presented here, which is resolved by BAT. For all the clusters we perform a detailed spectral analysis using XMM-Newton and Swift/BAT data to investigate the presence of a hard (non-thermal) X-ray excess. We find that in most cases the clusters emission in the 0.3-200 keV band can be explained by a multi-temperature thermal model confirming our previous results. For two clusters (Bullet and Abell 3667) we find evidence for the presence of a hard X-ray excess. In the case of the Bullet cluster, our analysis confirms the presence of a non-thermal, power-law like, component with a 20-100 keV flux of 3.4 x 10{sup -12} erg cm{sup -2} s{sup -1} as detected in previous studies. For Abell 3667 the excess emission can be successfully modeled as a hot component (kT = {approx}13 keV). We thus conclude that the hard X-ray emission from galaxy clusters (except the Bullet) has most likely thermal origin.

  13. Computer simulation of the probability that endangered whales will interact with oil spills

    SciTech Connect (OSTI)

    Reed, M.; Jayko, K.; Bowles, A.; Anderson, E.; Leatherwood, S.

    1987-03-01

    A numerical model system was developed to assess quantitatively the probability that endangered bowhead and gray whales will encounter spilled oil in Alaskan waters. Bowhead and gray whale migration and diving-surfacing models, and an oil-spill trajectory model comprise the system. The migration models were developed from conceptual considerations, then calibrated with and tested against observations. The movement of a whale point is governed by a random walk algorithm which stochastically follows a migratory pathway. The oil-spill model, developed under a series of other contracts, accounts for transport and spreading behavior in open water and in the presence of sea ice. Historical wind records and heavy, normal, or light ice cover data sets are selected at random to provide stochastic oil-spill scenarios for whale-oil interaction simulations.

  14. Direct comparison of defect ensembles extracted from damage probability and raster scan measurements

    SciTech Connect (OSTI)

    Batavičiūtė, G. Ščiuka, M.; Melninkaitis, A.

    2015-09-14

    The presented study addresses the characterization of nanometer sized defects acting as damage precursors in nanosecond laser pulse duration regime. Two approaches are used to extract distributions of localized damage precursors, namely, damage probability and damage density measurements. Testing is performed on uncoated and SiO{sub 2} monolayer film deposited fused silica substrate exposed with pulsed UV irradiation (355 nm, 4.8 ns). Then, a direct comparison of damage precursor ensembles obtained from both methods is carried out. Our analysis indicates apparent differences between both methods that are discussed in detail. Contamination by ablation products is identified as one of the key factors that influence damage density measurements.

  15. Theoretical analysis of integral neutron transport equation using collision probability method with quadratic flux approach

    SciTech Connect (OSTI)

    Shafii, Mohammad Ali Meidianti, Rahma Wildian, Fitriyani, Dian; Tongkukut, Seni H. J.; Arkundato, Artoto

    2014-09-30

    Theoretical analysis of integral neutron transport equation using collision probability (CP) method with quadratic flux approach has been carried out. In general, the solution of the neutron transport using the CP method is performed with the flat flux approach. In this research, the CP method is implemented in the cylindrical nuclear fuel cell with the spatial of mesh being conducted into non flat flux approach. It means that the neutron flux at any point in the nuclear fuel cell are considered different each other followed the distribution pattern of quadratic flux. The result is presented here in the form of quadratic flux that is better understanding of the real condition in the cell calculation and as a starting point to be applied in computational calculation.

  16. Focus Areas | Critical Materials Institute

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

    Focus Areas FA 1: Diversifying Supply FA 2: Developing Substitutes FA 3: Improving Reuse and Recycling FA 4: Crosscutting Research

  17. The snapshot Hubble U-band cluster survey (SHUCS). II. The star cluster population of NGC 2997

    SciTech Connect (OSTI)

    Ryon, J. E.; Gallagher, J. S. III; Adamo, A.; Bastian, N.; Smith, L. J.; Konstantopoulos, I. S.; Larsen, S.; Zackrisson, E.

    2014-08-01

    We study the star cluster population of NGC 2997, a giant spiral galaxy located at 9.5 Mpc and targeted by the Snapshot Hubble U-band Cluster Survey (SHUCS). Combining our U-band imaging from SHUCS with archival BVI imaging from the Hubble Space Telescope, we select a high confidence sample of clusters in the circumnuclear ring and disk through a combination of automatic detection procedures and visual inspection. The cluster luminosity functions in all four filters can be approximated by power laws with indices of 1.7 to 2.3. Some deviations from pure power-law shape are observed, hinting at the presence of a high-mass truncation in the cluster mass function. However, upon inspection of the cluster mass function, we find it is consistent with a pure power law of index 2.2 0.2 despite a slight bend at ?2.5 10{sup 4} M {sub ?}. No statistically significant truncation is observed. From the cluster age distributions, we find a low rate of disruption (? ? 0.1) in both the disk and circumnuclear ring. Finally, we estimate the cluster formation efficiency (?) over the last 100 Myr in each region, finding 7% 2% for the disk, 12% 4% for the circumnuclear ring, and 10% 3% for the entire UBVI footprint. This study highlights the need for wide-field UBVI coverage of galaxies to study cluster populations in detail, though a small sample of clusters can provide significant insight into the characteristics of the population.

  18. Galaxy cluster lensing masses in modified lensing potentials

    SciTech Connect (OSTI)

    Barreira, Alexandre; Li, Baojiu; Jennings, Elise; Merten, Julian; King, Lindsay; Baugh, Carlton M.; Pascoli, Silvia

    2015-10-28

    In this study, we determine the concentration–mass relation of 19 X-ray selected galaxy clusters from the Cluster Lensing and Supernova Survey with Hubble survey in theories of gravity that directly modify the lensing potential. We model the clusters as Navarro–Frenk–White haloes and fit their lensing signal, in the Cubic Galileon and Nonlocal gravity models, to the lensing convergence profiles of the clusters. We discuss a number of important issues that need to be taken into account, associated with the use of non-parametric and parametric lensing methods, as well as assumptions about the background cosmology. Our results show that the concentration and mass estimates in the modified gravity models are, within the error bars, the same as in Λ cold dark matter. This result demonstrates that, for the Nonlocal model, the modifications to gravity are too weak at the cluster redshifts, and for the Galileon model, the screening mechanism is very efficient inside the cluster radius. However, at distances ~ [2–20] Mpc/h from the cluster centre, we find that the surrounding force profiles are enhanced by ~ 20–40% in the Cubic Galileon model. This has an impact on dynamical mass estimates, which means that tests of gravity based on comparisons between lensing and dynamical masses can also be applied to the Cubic Galileon model.

  19. Optimizing weak lensing mass estimates for cluster profile uncertainty

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

    Gruen, D.; Bernstein, G. M.; Lam, T. Y.; Seitz, S.

    2011-09-11

    Weak lensing measurements of cluster masses are necessary for calibrating mass-observable relations (MORs) to investigate the growth of structure and the properties of dark energy. However, the measured cluster shear signal varies at fixed mass M200m due to inherent ellipticity of background galaxies, intervening structures along the line of sight, and variations in the cluster structure due to scatter in concentrations, asphericity and substructure. We use N-body simulated halos to derive and evaluate a weak lensing circular aperture mass measurement Map that minimizes the mass estimate variance <(Map - M200m)2> in the presence of all these forms of variability. Dependingmore » on halo mass and observational conditions, the resulting mass estimator improves on Map filters optimized for circular NFW-profile clusters in the presence of uncorrelated large scale structure (LSS) about as much as the latter improve on an estimator that only minimizes the influence of shape noise. Optimizing for uncorrelated LSS while ignoring the variation of internal cluster structure puts too much weight on the profile near the cores of halos, and under some circumstances can even be worse than not accounting for LSS at all. As a result, we discuss the impact of variability in cluster structure and correlated structures on the design and performance of weak lensing surveys intended to calibrate cluster MORs.« less

  20. NEW UBVRI PHOTOMETRY OF 234 M33 STAR CLUSTERS

    SciTech Connect (OSTI)

    Ma Jun

    2013-04-15

    This is the second paper of our series. In this paper, we present UBVRI photometry for 234 star clusters in the field of M33. For most of these star clusters, there is photometry in only two bands in previous studies. The photometry of these star clusters is performed using archival images from the Local Group Galaxies Survey, which covers 0.8 deg{sup 2} along the major axis of M33. Detailed comparisons show that, in general, our photometry is consistent with previous measurements, and in particular that our photometry is in good agreement with that of Zloczewski and Kaluzny. Combined with star cluster photometry in previous studies, we present some results: none of the M33 youngest clusters ({approx}10{sup 7} yr) have masses approaching 10{sup 5} M{sub Sun }, and comparisons with models of simple stellar populations suggest a large range of ages for M33 star clusters and some as old as the Galactic globular clusters.

  1. Optimizing weak lensing mass estimates for cluster profile uncertainty

    SciTech Connect (OSTI)

    Gruen, D.; Bernstein, G. M.; Lam, T. Y.; Seitz, S.

    2011-09-11

    Weak lensing measurements of cluster masses are necessary for calibrating mass-observable relations (MORs) to investigate the growth of structure and the properties of dark energy. However, the measured cluster shear signal varies at fixed mass M200m due to inherent ellipticity of background galaxies, intervening structures along the line of sight, and variations in the cluster structure due to scatter in concentrations, asphericity and substructure. We use N-body simulated halos to derive and evaluate a weak lensing circular aperture mass measurement Map that minimizes the mass estimate variance <(Map - M200m)2> in the presence of all these forms of variability. Depending on halo mass and observational conditions, the resulting mass estimator improves on Map filters optimized for circular NFW-profile clusters in the presence of uncorrelated large scale structure (LSS) about as much as the latter improve on an estimator that only minimizes the influence of shape noise. Optimizing for uncorrelated LSS while ignoring the variation of internal cluster structure puts too much weight on the profile near the cores of halos, and under some circumstances can even be worse than not accounting for LSS at all. As a result, we discuss the impact of variability in cluster structure and correlated structures on the design and performance of weak lensing surveys intended to calibrate cluster MORs.

  2. Galaxy cluster lensing masses in modified lensing potentials

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

    Barreira, Alexandre; Li, Baojiu; Jennings, Elise; Merten, Julian; King, Lindsay; Baugh, Carlton M.; Pascoli, Silvia

    2015-10-28

    In this study, we determine the concentration–mass relation of 19 X-ray selected galaxy clusters from the Cluster Lensing and Supernova Survey with Hubble survey in theories of gravity that directly modify the lensing potential. We model the clusters as Navarro–Frenk–White haloes and fit their lensing signal, in the Cubic Galileon and Nonlocal gravity models, to the lensing convergence profiles of the clusters. We discuss a number of important issues that need to be taken into account, associated with the use of non-parametric and parametric lensing methods, as well as assumptions about the background cosmology. Our results show that the concentrationmore » and mass estimates in the modified gravity models are, within the error bars, the same as in Λ cold dark matter. This result demonstrates that, for the Nonlocal model, the modifications to gravity are too weak at the cluster redshifts, and for the Galileon model, the screening mechanism is very efficient inside the cluster radius. However, at distances ~ [2–20] Mpc/h from the cluster centre, we find that the surrounding force profiles are enhanced by ~ 20–40% in the Cubic Galileon model. This has an impact on dynamical mass estimates, which means that tests of gravity based on comparisons between lensing and dynamical masses can also be applied to the Cubic Galileon model.« less

  3. Measuring consistent masses for 25 Milky Way globular clusters

    SciTech Connect (OSTI)

    Kimmig, Brian; Seth, Anil; Ivans, Inese I.; Anderton, Tim; Gregersen, Dylan; Strader, Jay; Caldwell, Nelson

    2015-02-01

    We present central velocity dispersions, masses, mass-to-light ratios (M/Ls ), and rotation strengths for 25 Galactic globular clusters (GCs). We derive radial velocities of 1951 stars in 12 GCs from single order spectra taken with Hectochelle on the MMT telescope. To this sample we add an analysis of available archival data of individual stars. For the full set of data we fit King models to derive consistent dynamical parameters for the clusters. We find good agreement between single-mass King models and the observed radial dispersion profiles. The large, uniform sample of dynamical masses we derive enables us to examine trends of M/L with cluster mass and metallicity. The overall values of M/L and the trends with mass and metallicity are consistent with existing measurements from a large sample of M31 clusters. This includes a clear trend of increasing M/L with cluster mass and lower than expected M/Ls for the metal-rich clusters. We find no clear trend of increasing rotation with increasing cluster metallicity suggested in previous work.

  4. X-ray spectroscopy of manganese clusters

    SciTech Connect (OSTI)

    Grush, M.M.

    1996-06-01

    Much of this thesis represents the groundwork necessary in order to probe Mn clusters more productively than with conventional Mn K-edge XAS and is presented in Part 1. Part 2 contains the application of x-ray techniques to Mn metalloproteins and includes a prognosis at the end of each chapter. Individual Mn oxidation states are more readily distinguishable in Mn L-edge spectra. An empirical mixed valence simulation routine for determining the average Mn oxidation state has been developed. The first Mn L-edge spectra of a metalloprotein were measured and interpreted. The energy of Mn K{beta} emission is strongly correlated with average Mn oxidation state. K{beta} results support oxidation states of Mn(III){sub 2}(IV){sub 2} for the S{sub 1} state of Photosystem II chemical chemically reduced preparations contain predominantly Mn(II). A strength and limitation of XAS is that it probes all of the species of a particular element in a sample. It would often be advantageous to selectively probe different forms of the same element. The first demonstration that chemical shifts in x-ray fluorescence energies can be used to obtain oxidation state-selective x-ray absorption spectra is presented. Spin-dependent spectra can also be used to obtain a more simplified picture of local structure. The first spin-polarized extended x-ray absorption fine structure using Mn K{beta} fluorescence detection is shown.

  5. Cosmological simulations of isotropic conduction in galaxy clusters

    SciTech Connect (OSTI)

    Smith, Britton; O'Shea, Brian W.; Voit, G. Mark; Ventimiglia, David; Skillman, Samuel W.

    2013-12-01

    Simulations of galaxy clusters have a difficult time reproducing the radial gas-property gradients and red central galaxies observed to exist in the cores of galaxy clusters. Thermal conduction has been suggested as a mechanism that can help bring simulations of cluster cores into better alignment with observations by stabilizing the feedback processes that regulate gas cooling, but this idea has not yet been well tested with cosmological numerical simulations. Here we present cosmological simulations of 10 galaxy clusters performed with five different levels of isotropic Spitzer conduction, which alters both the cores and outskirts of clusters, though not dramatically. In the cores, conduction flattens central temperature gradients, making them nearly isothermal and slightly lowering the central density, but failing to prevent a cooling catastrophe there. Conduction has little effect on temperature gradients outside of cluster cores because outward conductive heat flow tends to inflate the outer parts of the intracluster medium (ICM), instead of raising its temperature. In general, conduction tends reduce temperature inhomogeneity in the ICM, but our simulations indicate that those homogenizing effects would be extremely difficult to observe in ?5 keV clusters. Outside the virial radius, our conduction implementation lowers the gas densities and temperatures because it reduces the Mach numbers of accretion shocks. We conclude that, despite the numerous small ways in which conduction alters the structure of galaxy clusters, none of these effects are significant enough to make the efficiency of conduction easily measurable, unless its effects are more pronounced in clusters hotter than those we have simulated.

  6. Co-evolution of galactic nuclei and globular cluster systems

    SciTech Connect (OSTI)

    Gnedin, Oleg Y.; Ostriker, Jeremiah P.; Tremaine, Scott

    2014-04-10

    We revisit the hypothesis that dense galactic nuclei are formed from inspiraling globular clusters. Recent advances in the understanding of the continuous formation of globular clusters over cosmic time and the concurrent evolution of the galaxy stellar distribution allow us to construct a simple model that matches the observed spatial and mass distributions of clusters in the Galaxy and the giant elliptical galaxy M87. In order to compare with observations, we model the effects of dynamical friction and dynamical evolution, including stellar mass loss, tidal stripping of stars, and tidal disruption of clusters by the growing galactic nucleus. We find that inspiraling globular clusters form a dense central structure, with mass and radius comparable to the typical values in observed nuclear star clusters (NSCs) in late-type and low-mass early-type galaxies. The density contrast associated with the NSC is less pronounced in giant elliptical galaxies. Our results indicate that the NSC mass as a fraction of mass of the galaxy stellar spheroid scales as M{sub NSC}/M{sub ?}?0.0025 M{sub ?,11}{sup ?0.5}. Thus disrupted globular clusters could contribute most of the mass of NSCs in galaxies with stellar mass below 10{sup 11} M {sub ?}. The inner part of the accumulated cluster may seed the growth of a central black hole via stellar dynamical core collapse, thereby relieving the problem of how to form luminous quasars at high redshift. The seed black hole may reach ?10{sup 5} M {sub ?} within ? 1 Gyr of the beginning of globular cluster formation.

  7. Geothermal resource area 9: Nye County. Area development plan

    SciTech Connect (OSTI)

    Pugsley, M.

    1981-01-01

    Geothermal Resource area 9 encompasses all of Nye County, Nevada. Within this area there are many different known geothermal sites ranging in temperature from 70/sup 0/ to over 265/sup 0/ F. Fifteen of the more major sites have been selected for evaluation in this Area Development Plan. Various potential uses of the energy found at each of the resource sites discussed in this Area Development Plan were determined after evaluating the area's physical characteristics, land ownership and land use patterns, existing population and projected growth rates, and transportation facilities, and comparing those with the site specific resource characteristics. The uses considered were divided into five main categories: electrical generation, space heating, recreation, industrial process heat, and agriculture. Within two of these categories certain subdivisions were considered separately. The findings about each of the 15 geothermal sites considered in this Area Development Plan are summarized.

  8. Regional hydrology of the Green River-Moab area, northwestern Paradox Basin, Utah

    SciTech Connect (OSTI)

    Rush, F.E.; Whitfield, M.S.; Hart, I.M.

    1982-12-01

    The Green River-Moab area encompasses about 7800 square kilometers or about 25% of the Paradox basin. The entire Paradox basin is a part of the Colorado Plateaus that is underlain by a thick sequence of evaporite (salt) beds of Pennsylvanian age. The rock units that underlie the area have been grouped into hydrogeologic units based on their water-transmitting ability. Confining beds consist of evaporite beds of mostly salt, and overlying and underlying thick sequences of rocks with minimal permeability; above and below these confining beds are aquifers. The upper Mesozoic sandstone aquifer, probably is the most permeable hydrogeologic unit of the area and is the subject of this investigation. The principal component of groundwater outflow from this aquifer probably is subsurface flow to regional streams (the Green and Colorado Rivers) and is about 100 million cubic meters per year. All other components of outflow are relatively small. The average annual recharge to the aquifer is about 130 million cubic meters, of which about 20 million cubic meters is from local precipitation. For the lower aquifer, all recharge and discharge probably is by subsurface flow and was not estimated. The aquifers are generally isolated from the evaporite beds by the bounding confining beds; as a result, most ground water has little if any contact with the evaporites. Brines are present in the confining beds, but solution of beds of salt probably is very slow in most parts of the area. No brine discharges have been identified.

  9. SSL Demonstration: Area Lighting, Yuma Sector Border Patrol Area, AZ

    SciTech Connect (OSTI)

    2015-05-28

    Along the Yuma Sector Border Patrol Area in Yuma, Arizona, the GATEWAY program conducted a trial demonstration in which the incumbent quartz metal halide area lighting was replaced with LED at three pole locations at the Yuma Sector Border Patrol Area in Yuma, Arizona. The retrofit was documented to better understand LED technology performance in high-temperature environments. This document is a summary brief of the Phase 1.0 and 1.1 reports previously published on this demonstration.

  10. Desert Peak Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Desert Peak Geothermal Area (Redirected from Desert Peak Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Desert Peak Geothermal Area Contents 1 Area Overview 2...

  11. PPPL Area Map | Princeton Plasma Physics Lab

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

    PPPL Area Map View Larger Map

  12. Property:GeothermalArea | Open Energy Information

    Open Energy Info (EERE)

    Area + Babadere Geothermal Project + Tuzla Geothermal Area + Bacman 1 GEPP + Bac-Man Laguna Geothermal Area + Bacman 2 GEPP + Bac-Man Laguna Geothermal Area + Bacman...

  13. Cove Fort Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Cove Fort Geothermal Area (Redirected from Cove Fort Geothermal Area - Vapor) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Cove Fort Geothermal Area Contents 1 Area...

  14. Blue Mountain Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Blue Mountain Geothermal Area (Redirected from Blue Mountain Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Blue Mountain Geothermal Area Contents 1 Area...

  15. Stillwater Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Stillwater Geothermal Area (Redirected from Stillwater Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Stillwater Geothermal Area Contents 1 Area Overview 2...

  16. Chena Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Chena Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Chena Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 2.1 Chena Area...

  17. Salton Sea Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Salton Sea Geothermal Area (Redirected from Salton Sea Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Salton Sea Geothermal Area Contents 1 Area Overview 2...

  18. Heber Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Heber Geothermal Area (Redirected from Heber Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Heber Geothermal Area Contents 1 Area Overview 2 History and...

  19. REVISITING SCALING RELATIONS FOR GIANT RADIO HALOS IN GALAXY CLUSTERS

    SciTech Connect (OSTI)

    Cassano, R.; Brunetti, G.; Venturi, T.; Kale, R.; Pratt, G. W.; Markevitch, M.

    2013-11-10

    Many galaxy clusters host megaparsec-scale radio halos, generated by ultrarelativistic electrons in the magnetized intracluster medium. Correlations between the synchrotron power of radio halos and the thermal properties of the hosting clusters were established in the last decade, including the connection between the presence of a halo and cluster mergers. The X-ray luminosity and redshift-limited Extended GMRT Radio Halo Survey provides a rich and unique dataset for statistical studies of the halos. We uniformly analyze the radio and X-ray data for the GMRT cluster sample, and use the new Planck Sunyaev-Zel'dovich (SZ) catalog to revisit the correlations between the power of radio halos and the thermal properties of galaxy clusters. We find that the radio power at 1.4 GHz scales with the cluster X-ray (0.1-2.4 keV) luminosity computed within R{sub 500} as P{sub 1.4}∼L{sup 2.1±0.2}{sub 500}. Our bigger and more homogenous sample confirms that the X-ray luminous (L{sub 500} > 5 × 10{sup 44} erg s{sup –1}) clusters branch into two populations—radio halos lie on the correlation, while clusters without radio halos have their radio upper limits well below that correlation. This bimodality remains if we excise cool cores from the X-ray luminosities. We also find that P{sub 1.4} scales with the cluster integrated SZ signal within R{sub 500}, measured by Planck, as P{sub 1.4}∼Y{sup 2.05±0.28}{sub 500}, in line with previous findings. However, contrary to previous studies that were limited by incompleteness and small sample size, we find that 'SZ-luminous' Y{sub 500} > 6 × 10{sup –5} Mpc{sup 2} clusters show a bimodal behavior for the presence of radio halos, similar to that in the radio-X-ray diagram. Bimodality of both correlations can be traced to clusters dynamics, with radio halos found exclusively in merging clusters. These results confirm the key role of mergers for the origin of giant radio halos, suggesting that they trigger the relativistic particle

  20. Mapping compound cosmic telescopes containing multiple projected cluster-scale halos

    SciTech Connect (OSTI)

    Ammons, S. Mark; Wong, Kenneth C.; Zabludoff, Ann I.; Keeton, Charles R. E-mail: kwong@as.arizona.edu E-mail: keeton@physics.rutgers.edu

    2014-01-20

    Lines of sight with multiple projected cluster-scale gravitational lenses have high total masses and complex lens plane interactions that can boost the area of magnification, or tendue, making detection of faint background sources more likely than elsewhere. To identify these new 'compound' cosmic telescopes, we have found directions in the sky with the highest integrated mass densities, as traced by the projected concentrations of luminous red galaxies (LRGs). We use new galaxy spectroscopy to derive preliminary magnification maps for two such lines of sight with total mass exceeding ?3 10{sup 15} M {sub ?}. From 1151 MMT Hectospec spectra of galaxies down to i {sub AB} = 21.2, we identify two to three group- and cluster-scale halos in each beam. These are well traced by LRGs. The majority of the mass in beam J085007.6+360428 (0850) is contributed by Zwicky 1953, a massive cluster at z = 0.3774, whereas beam J130657.5+463219 (1306) is composed of three halos with virial masses of 6 10{sup 14}-2 10{sup 15} M {sub ?}, one of which is A1682. The magnification maps derived from our mass models based on spectroscopy and Sloan Digital Sky Survey photometry alone display substantial tendue: the 68% confidence bands on the lens plane area with magnification exceeding 10 for a source plane of z{sub s} = 10 are [1.2, 3.8] arcmin{sup 2} for 0850 and [2.3, 6.7] arcmin{sup 2} for 1306. In deep Subaru Suprime-Cam imaging of beam 0850, we serendipitously discover a candidate multiply imaged V-dropout source at z {sub phot} = 5.03. The location of the candidate multiply imaged arcs is consistent with the critical curves for a source plane of z = 5.03 predicted by our mass model. Incorporating the position of the candidate multiply imaged galaxy as a constraint on the critical curve location in 0850 narrows the 68% confidence band on the lens plane area with ? > 10 and z{sub s} = 10 to [1.8, 4.2] arcmin{sup 2}, an tendue range comparable to that of MACS 0717+3745 and El

  1. Moment-Based Probability Modeling and Extreme Response Estimation, The FITS Routine Version 1.2

    SciTech Connect (OSTI)

    MANUEL,LANCE; KASHEF,TINA; WINTERSTEIN,STEVEN R.

    1999-11-01

    This report documents the use of the FITS routine, which provides automated fits of various analytical, commonly used probability models from input data. It is intended to complement the previously distributed FITTING routine documented in RMS Report 14 (Winterstein et al., 1994), which implements relatively complex four-moment distribution models whose parameters are fit with numerical optimization routines. Although these four-moment fits can be quite useful and faithful to the observed data, their complexity can make them difficult to automate within standard fitting algorithms. In contrast, FITS provides more robust (lower moment) fits of simpler, more conventional distribution forms. For each database of interest, the routine estimates the distribution of annual maximum response based on the data values and the duration, T, over which they were recorded. To focus on the upper tails of interest, the user can also supply an arbitrary lower-bound threshold, {chi}{sub low}, above which a shifted distribution model--exponential or Weibull--is fit.

  2. Development and methodology of level 1 probability safety assessment at PUSPATI TRIGA Reactor

    SciTech Connect (OSTI)

    Maskin, Mazleha; Tom, Phongsakorn Prak; Lanyau, Tonny Anak; Saad, Mohamad Fauzi; Ismail, Ahmad Razali; Abu, Mohamad Puad Haji; Brayon, Fedrick Charlie Matthew; Mohamed, Faizal

    2014-02-12

    As a consequence of the accident at the Fukushima Dai-ichi Nuclear Power Plant in Japan, the safety aspects of the one and only research reactor (31 years old) in Malaysia need be reviewed. Based on this decision, Malaysian Nuclear Agency in collaboration with Atomic Energy Licensing Board and Universiti Kebangsaan Malaysia develop a Level-1 Probability Safety Assessment on this research reactor. This work is aimed to evaluate the potential risks of incidents in RTP and at the same time to identify internal and external hazard that may cause any extreme initiating events. This report documents the methodology in developing a Level 1 PSA performed for the RTP as a complementary approach to deterministic safety analysis both in neutronics and thermal hydraulics. This Level-1 PSA work has been performed according to the procedures suggested in relevant IAEA publications and at the same time numbers of procedures has been developed as part of an Integrated Management System programme implemented in Nuclear Malaysia.

  3. Probability of loss of assured safety in systems with multiple time-dependent failure modes.

    SciTech Connect (OSTI)

    Helton, Jon Craig; Pilch, Martin M.; Sallaberry, Cedric M.

    2012-09-01

    Weak link (WL)/strong link (SL) systems are important parts of the overall operational design of high-consequence systems. In such designs, the SL system is very robust and is intended to permit operation of the entire system under, and only under, intended conditions. In contrast, the WL system is intended to fail in a predictable and irreversible manner under accident conditions and render the entire system inoperable before an accidental operation of the SL system. The likelihood that the WL system will fail to deactivate the entire system before the SL system fails (i.e., degrades into a configuration that could allow an accidental operation of the entire system) is referred to as probability of loss of assured safety (PLOAS). Representations for PLOAS for situations in which both link physical properties and link failure properties are time-dependent are derived and numerically evaluated for a variety of WL/SL configurations, including PLOAS defined by (i) failure of all SLs before failure of any WL, (ii) failure of any SL before failure of any WL, (iii) failure of all SLs before failure of all WLs, and (iv) failure of any SL before failure of all WLs. The effects of aleatory uncertainty and epistemic uncertainty in the definition and numerical evaluation of PLOAS are considered.

  4. {ital E}3 transition probabilities in the platinum, mercury, and lead isotopes

    SciTech Connect (OSTI)

    Egido, J.L.; Martin, V.; Robledo, L.M.; Sun, Y.

    1996-06-01

    Spectroscopical properties of the platinum, mercury, and lead isotopes are studied within the Hartree-Fock plus BCS framework with the finite range density-dependent Gogny force. These properties are also studied beyond mean-field theory by combining the use of generator-coordinate-method-like wave functions with the angular momentum projection technique as to generate many-body correlated wave functions that are at the same time eigenstates of the angular momentum operator. We apply this formalism to the calculation of reduced transition probabilities {ital B}({ital E}3) from the lowest-lying octupole collective state to the ground state of several isotopes of the platinum, mercury, and lead nuclei whose experimental {ital B}({ital E}3) values present a peculiar behavior. The projected calculations show a large improvement over the unprojected ones when compared with the experimental data. The unprojected calculations are unable to predict any structure in the {ital B}({ital E}3). {copyright} {ital 1996 The American Physical Society.}

  5. Long-Term Probability Distribution of Wind Turbine Planetary Bearing Loads (Poster)

    SciTech Connect (OSTI)

    Jiang, Z.; Xing, Y.; Guo, Y.; Dong, W.; Moan, T.; Gao, Z.

    2013-04-01

    Among the various causes of bearing damage and failure, metal fatigue of the rolling contact surface is the dominant failure mechanism. The fatigue life is associated with the load conditions under which wind turbines operate in the field. Therefore, it is important to understand the long-term distribution of the bearing loads under various environmental conditions. The National Renewable Energy Laboratory's 750-kW Gearbox Reliability Collaborative wind turbine is studied in this work. A decoupled analysis using several computer codes is carried out. The global aero-elastic simulations are performed using HAWC2. The time series of the drivetrain loads and motions from the global dynamic analysis are fed to a drivetrain model in SIMPACK. The time-varying internal pressure distribution along the raceway is obtained analytically. A series of probability distribution functions are then used to fit the long-term statistical distribution at different locations along raceways. The long-term distribution of the bearing raceway loads are estimated under different environmental conditions. Finally, the bearing fatigue lives are calculated.

  6. Track 2 sites: Guidance for assessing low probability hazard sites at the INEL. Revision 6

    SciTech Connect (OSTI)

    Not Available

    1994-01-01

    This document presents guidance for assessment of Track 2 low probability hazard sites (LPHS) at the Idaho National Engineering Laboratory (INEL). The Track 2 classification was developed specifically for the INEL to streamline the implementation of Comprehensive Environmental Response, Compensation, and Liability Act. Track 2 LPHSs are described as sites where insufficient data are available to make a decision concerning the risk level or to select or design a remedy. As such, these types of sites are not described in the National Contingency Plan or existing regulatory guidance. The goal of the Track 2 process is to evaluate LPHSs using existing qualitative and quantitative data to minimize the collection of new environmental data. To this end, this document presents a structured format consisting of a series of questions and tables. A qualitative risk assessment is used. The process is iterative, and addresses an LPHS from multiple perspectives (i.e., historical, empirical, process) in an effort to generate a reproducible and defensible method. This rigorous approach follows the data quality objective process and establishes a well organized, logical approach to consolidate and assess existing data, and set decision criteria. If necessary, the process allows for the design of a sampling and analysis strategy to obtain new environmental data of appropriate quality to support decisions for each LPHS. Finally, the guidance expedites consensus between regulatory parties by emphasizing a team approach to Track 2 investigations.

  7. E2 transition probabilities for decays of isomers observed in neutron-rich odd Sn isotopes

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

    Iskra, Ł. W.; Broda, R.; Janssens, R. V.F.; Wrzesiński, J.; Chiara, C. J.; Carpenter, M. P.; Fornal, B.; Hoteling, N.; Kondev, F. G.; Królas, W.; et al

    2015-01-01

    High-spin states were investigated with gamma coincidence techniques in neutron-rich Sn isotopes produced in fission processes following ⁴⁸Ca + ²⁰⁸Pb, ⁴⁸Ca + ²³⁸U, and ⁶⁴Ni + ²³⁸U reactions. By exploiting delayed and cross-coincidence techniques, level schemes have been delineated in odd ¹¹⁹⁻¹²⁵Sn isotopes. Particular attention was paid to the occurrence of 19/2⁺ and 23/2⁺ isomeric states for which the available information has now been significantly extended. Reduced transition probabilities, B(E2), extracted from the measured half-lives and the established details of the isomeric decays exhibit a striking regularity. This behavior was compared with the previously observed regularity of the B(E2) amplitudesmore » for the seniority ν = 2 and 3, 10⁺ and 27/2⁻ isomers in even- and odd-Sn isotopes, respectively.« less

  8. System and method for merging clusters of wireless nodes in a wireless network

    DOE Patents [OSTI]

    Budampati, Ramakrishna S.; Gonia, Patrick S.; Kolavennu, Soumitri N.; Mahasenan, Arun V.

    2012-05-29

    A system includes a first cluster having multiple first wireless nodes. One first node is configured to act as a first cluster master, and other first nodes are configured to receive time synchronization information provided by the first cluster master. The system also includes a second cluster having one or more second wireless nodes. One second node is configured to act as a second cluster master, and any other second nodes configured to receive time synchronization information provided by the second cluster master. The system further includes a manager configured to merge the clusters into a combined cluster. One of the nodes is configured to act as a single cluster master for the combined cluster, and the other nodes are configured to receive time synchronization information provided by the single cluster master.

  9. {alpha}-cluster states in N{ne}Z nuclei

    SciTech Connect (OSTI)

    Goldberg, V. Z.; Rogachev, G. V.

    2012-10-20

    The importance of studies of {alpha}-Cluster structure in N{ne}Z light nuclei is discussed. Spin-parity assignments for the low-lying levels in {sup 10}C are suggested.

  10. Generation of beams of refractory-metal clusters

    SciTech Connect (OSTI)

    Wexler, S.; Riley, R.J.; Parks, E.K.; Mao, C.R.; Pobo, L.G.

    1982-01-01

    Interest in the physical and chemical properties of small metal clusters has recently stimulated the development of sources for the generation of molecular beams of metal clusters, since the collision-free environment of a beam has the advantage of permitting in-flight study of isolated species free of interference from surroundings. For example, spectroscopic studies utilizing tunable lasers may be performed in the molecular beam environment. The objectives of our research program are the elucidation of the physical and chemical properties of clusters of refractory metal atoms, in particular those of the catalytically active transition metals. For these purposes we have built and tested two sources suitable for generation of cluster beams of refractory metals, one for continuous beams and the other for pulsed beams.

  11. Construction of Heterometallic Clusters in a small peptide scaffold...

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

    Construction of Heterometallic Clusters in a small peptide scaffold as NiFe-hydrogenase ... Authors: Dutta, A., Hamilton, G. A., Hartnett, H. E., Jones, A. K. Title: Construction of ...

  12. Visual cluster analysis and pattern recognition template and methods

    DOE Patents [OSTI]

    Osbourn, Gordon Cecil; Martinez, Rubel Francisco

    1999-01-01

    A method of clustering using a novel template to define a region of influence. Using neighboring approximation methods, computation times can be significantly reduced. The template and method are applicable and improve pattern recognition techniques.

  13. Weak Lensing by Galaxy Clusters: from Pixels to Cosmology

    SciTech Connect (OSTI)

    Gruen, Daniel

    2015-03-11

    The story of the origin and evolution of our Universe is told, equivalently, by space-time itself and by the structures that grow inside of it. Clusters of galaxies are the frontier of bottom-up structure formation. They are the most massive objects to have collapsed at the present epoch. By that virtue, their abundance and structural parameters are highly sensitive to the composition and evolution of the Universe. The most common probe of cluster cosmology, abundance, uses samples of clusters selected by some observable. Applying a mass-observable relation (MOR), cosmological parameters can be constrained by comparing the sample to predicted cluster abundances as a function of observable and redshift. Arguably, however, cluster probes have not yet entered the era of per cent level precision cosmology. The primary reason for this is our imperfect understanding of the MORs. The overall normalization, the slope of mass vs. observable, the redshift evolution, and the degree and correlation of intrinsic scatters of observables at fixed mass have to be constrained for interpreting abundances correctly. Mass measurement of clusters by means of the differential deflection of light from background sources in their gravitational field, i.e. weak lensing, is a powerful approach for achieving this. This thesis presents new methods for and scientific results of weak lensing measurements of clusters of galaxies. The former include, on the data reduction side, (i) the correction of CCD images for non-linear effects due to the electric fields of accumulated charges and (ii) a method for masking artifact features in sets of overlapping images of the sky by comparison to the median image. Also, (iii) I develop a method for the selection of background galaxy samples based on their color and apparent magnitude that includes a new correction for contamination with cluster member galaxies. The main scientific results are the following. (i) For the Hubble Frontier Field cluster RXC J

  14. Undecametallic and hexadecametallic ferric oxo–hydroxo/ethoxo pivalate clusters

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

    Baca, Svetlana G.; Speldrich, Manfred; van Leusen, Jan; Ellern, Arkady; Kögerler, Paul

    2015-03-27

    The synthesis strategies for highly condensed {Fe11} and {Fe16} pivalate clusters have been developed based on archetypal geometrically frustrated triangular {Fe3(μ3-O)} motifs that are interlinked via oxo, hydroxo, ethoxo, and carboxylate groups.

  15. Linked supramolecular building blocks for enhanced cluster formation

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

    McLellan, Ross; Palacios, Maria A.; Beavers, Christine M.; Teat, Simon J.; Piligkos, Stergios; Brechin, Euan K.; Dalgarno, Scott J.

    2015-01-09

    Methylene-bridged calix[4]arenes have emerged as extremely versatile ligand supports in the formation of new polymetallic clusters possessing fascinating magnetic properties. Metal ion binding rules established for this building block allow one to partially rationalise the complex assembly process. The ability to covalently link calix[4]arenes at the methylene bridge provides significantly improved control over the introduction of different metal centres to resulting cluster motifs. Clusters assembled from bis-calix[4]arenes and transition metal ions or 3d-4f combinations display characteristic features of the analogous calix[4]arene supported clusters, thereby demonstrating an enhanced and rational approach towards the targeted synthesis of complex and challenging structures.

  16. Linked supramolecular building blocks for enhanced cluster formation

    SciTech Connect (OSTI)

    McLellan, Ross; Palacios, Maria A.; Beavers, Christine M.; Teat, Simon J.; Piligkos, Stergios; Brechin, Euan K.; Dalgarno, Scott J.

    2015-01-09

    Methylene-bridged calix[4]arenes have emerged as extremely versatile ligand supports in the formation of new polymetallic clusters possessing fascinating magnetic properties. Metal ion binding rules established for this building block allow one to partially rationalise the complex assembly process. The ability to covalently link calix[4]arenes at the methylene bridge provides significantly improved control over the introduction of different metal centres to resulting cluster motifs. Clusters assembled from bis-calix[4]arenes and transition metal ions or 3d-4f combinations display characteristic features of the analogous calix[4]arene supported clusters, thereby demonstrating an enhanced and rational approach towards the targeted synthesis of complex and challenging structures.

  17. Visual cluster analysis and pattern recognition template and methods

    DOE Patents [OSTI]

    Osbourn, G.C.; Martinez, R.F.

    1999-05-04

    A method of clustering using a novel template to define a region of influence is disclosed. Using neighboring approximation methods, computation times can be significantly reduced. The template and method are applicable and improve pattern recognition techniques. 30 figs.

  18. Probing the Unique Size-Dependent Properties of Small Au Clusters, Au Alloy Clusters, and CO Chemisorbed Au Clusters in the Gas Phase

    SciTech Connect (OSTI)

    Zhai, Hua-jin; Li, Xi; Wang, Lai S.

    2007-04-01

    When materials are reduced in size to the nanometer scale, their physical and chemical properties undergo major changes and become size-dependent, forming the foundation for nanoscience and nanotechnology. Gold nanoparticles and small gold clusters have been the focus of intensive research activities lately. The modern goldrush is largely motivated by the recent discoveries that (i) nanogold shows unexpected catalytic properties for a wide spectrum of chemical reactions [1], (ii) nanogold enables selective binding to biomolecules such as DNA and thus can serve as biosensors [2], (iii) gold has important potential applications in nanoelectronics [3,4], and (iv) gold clusters and gold-containing compounds possess unique chemical properties [5]. All these golden discoveries have made gold a surprising and rewarding subject of investigation in nanoscience and cluster science. Indeed, some of our oldest notions regarding gold, such as its inertness, are being changed dramatically by the recent findings in nanogold.

  19. NNSA Announces Procurement of Penguin Computing Clusters to Support

    National Nuclear Security Administration (NNSA)

    Stockpile Stewardship at National Labs | National Nuclear Security Administration | (NNSA) Announces Procurement of Penguin Computing Clusters to Support Stockpile Stewardship at National Labs October 20, 2015 The National Nuclear Security Administration's (NNSA's) Lawrence Livermore National Laboratory today announced the awarding of a subcontract to Penguin Computing - a leading developer of high-performance Linux cluster computing systems based in Silicon Valley - to bolster computing for

  20. Method and apparatus for the production of cluster ions

    DOE Patents [OSTI]

    Friedman, L.; Beuhler, R.J.

    A method and apparatus for the production of cluster ions, and preferably isotopic hydrogen cluster ions is disclosed. A gas, preferably comprising a carrier gas and a substrate gas, is cooled to about its boiling point and expanded through a supersonic nozzle into a region maintained at a low pressure. Means are provided for the generation of a plasma in the gas before or just as it enters the nozzle.

  1. Analysis of a Cluster Strategy for Near Term Hydrogen Infrastructure

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

    Rollout in Southern California | Department of Energy a Cluster Strategy for Near Term Hydrogen Infrastructure Rollout in Southern California Analysis of a Cluster Strategy for Near Term Hydrogen Infrastructure Rollout in Southern California Presentation at the Renewable Hydrogen Workshop, Nov. 16, 2009, in Palm Springs, CA renewable_hydrogen_workshop_nov16_nicholas.pdf (1.64 MB) More Documents & Publications Hydrogen Supply: Cost Estimate for Hydrogen Pathways-Scoping Analysis. January

  2. MPI AND OPENMP PARADIGMS ON CLUSTER OF SMP ARCHITECTURES: THE

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

    AND OPENMP PARADIGMS ON CLUSTER OF SMP ARCHITECTURES: THE VACANCY TRACKING ALGORITHM FOR MULTI-DIMENSIONAL ARRAY TRANSPOSITION YUN HE AND CHRIS H. Q. DING Abstract. We evaluate remapping multi-dimensional arrays on cluster of SMP architectures under OpenMP, MPI, and hybrid paradigms. Traditional method of multi-dimensional array transpose needs an auxiliary array of the same size and a copy back stage. We recently developed an in-place method using vacancy tracking cycles. The vacancy tracking

  3. Genomic analyses of bacterial porin-cytochrome gene clusters

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

    Shi, Liang; Fredrickson, James K.; Zachara, John M.

    2014-11-26

    In this study, the porin-cytochrome (Pcc) protein complex is responsible for trans-outer membrane electron transfer during extracellular reduction of Fe(III) by the dissimilatory metal-reducing bacterium Geobacter sulfurreducens PCA. The identified and characterized Pcc complex of G. sulfurreducens PCA consists of a porin-like outer-membrane protein, a periplasmic 8-heme c type cytochrome (c-Cyt) and an outer-membrane 12-heme c-Cyt, and the genes encoding the Pcc proteins are clustered in the same regions of genome (i.e., the pcc gene clusters) of G. sulfurreducens PCA. A survey of additionally microbial genomes has identified the pcc gene clusters in all sequenced Geobacter spp. and other bacteriamore » from six different phyla, including Anaeromyxobacter dehalogenans 2CP-1, A. dehalogenans 2CP-C, Anaeromyxobacter sp. K, Candidatus Kuenenia stuttgartiensis, Denitrovibrio acetiphilus DSM 12809, Desulfurispirillum indicum S5, Desulfurivibrio alkaliphilus AHT2, Desulfurobacterium thermolithotrophum DSM 11699, Desulfuromonas acetoxidans DSM 684, Ignavibacterium album JCM 16511, and Thermovibrio ammonificans HB-1. The numbers of genes in the pcc gene clusters vary, ranging from two to nine. Similar to the metal-reducing (Mtr) gene clusters of other Fe(III)-reducing bacteria, such as Shewanella spp., additional genes that encode putative c-Cyts with predicted cellular localizations at the cytoplasmic membrane, periplasm and outer membrane often associate with the pcc gene clusters. This suggests that the Pcc-associated c-Cyts may be part of the pathways for extracellular electron transfer reactions. The presence of pcc gene clusters in the microorganisms that do not reduce solid-phase Fe(III) and Mn(IV) oxides, such as D. alkaliphilus AHT2 and I. album JCM 16511, also suggests that some of the pcc gene clusters may be involved in extracellular electron transfer reactions with the substrates other than Fe(III) and Mn(IV) oxides.« less

  4. Aqueous sulfate separation by crystallization of sulfate–water clusters

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

    Custelcean, Radu; Williams, Neil J.; Seipp, Charles A.

    2015-08-07

    An effective approach to separating sulfates from aqueous solutions is based on the crystallization of extended [SO4(H2O) 52-]n sulfate–water clusters with a bis(guanidinium) ligand. The ligand was generated in situ by hydrazone condensation in water, thus avoiding elaborate syntheses, tedious purifications, and organic solvents. Crystallization of sulfate–water clusters represents an alternative to the now established sulfate separation strategies that involve encapsulating the “naked” anion.

  5. Method and apparatus for the production of cluster ions

    DOE Patents [OSTI]

    Friedman, Lewis; Beuhler, Robert J.

    1988-01-01

    A method and apparatus for the production of cluster ions, and preferably isotopic hydrogen cluster ions is disclosed. A gas, preferably comprising a carrier gas and a substrate gas, is cooled to about its boiling point and expanded through a supersonic nozzle into a region maintained at a low pressure. Means are provided for the generation of a plasma in the gas before or just as it enters the nozzle.

  6. Clusters of antibiotic resistance genes enriched together stay together in

    Office of Scientific and Technical Information (OSTI)

    swine agriculture (Journal Article) | SciTech Connect Clusters of antibiotic resistance genes enriched together stay together in swine agriculture Citation Details In-Document Search Title: Clusters of antibiotic resistance genes enriched together stay together in swine agriculture Antibiotic resistance is a worldwide health risk, but the influence of animal agriculture on the genetic context and enrichment of individual antibiotic resistance alleles remains unclear. Using quantitative PCR

  7. High Temperature Membrane with HUmidification-Independent Cluster Structure

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

    | Department of Energy with HUmidification-Independent Cluster Structure High Temperature Membrane with HUmidification-Independent Cluster Structure A presentation to the High Temperature Membranes Working Group meeting, May 19, 2006. lipp.pdf (132.46 KB) More Documents & Publications High Temperature Membrane Working Group New Proton Conductive Composit Materials with Co-continuous Phases Using Functionalized and Crosslinkable TFE/VDF Fluoropolymers High temperature membranes for DMFC

  8. The annual probability of an aircraft crash on the US Department of Energy reservation in Oak Ridge, Tennessee

    SciTech Connect (OSTI)

    Seigler, R.S.; Luttrell, L.J.

    1992-11-01

    Aircraft hazards were evaluated to determine the total annual probability of an aircraft crash occurring at any structure located on the US Department of Energy (DOE) reservation in Oak Ridge, Tennessee. This report documents the use of an accepted methodology for calculating the probability of an aircraft crash as applied to the three Oak Ridge plant sites including the adjoining facilities. Based on the data contained herein, the evaluation concluded that the probability of an aircraft crash occurrence at a single facility is generally considered ``not credible`` as defined in DOE/OR-901. Additionally, reevaluation of probabilities would be necessary if significant changes were made to local air traffic. The probability of an aircraft crash could increase as a result of the opening of any new airport or heliport in the vicinity; a greater volume of air traffic from McGhee Tyson airport in Knoxville, should the airport status change from feeder airport to hub airport; the rerouting of commercial and/or military flights at the McGhee Tyson airport; and finally, a change in direction or the addition of a federal airway. At one time, DOE planned to establish a zone of prohibited airspace over the Y-12 plant; if the plans are enacted in the future, the probability of an aircraft crash at the Y-12 plant could decrease. Pilots since have been voluntarily requested not to fly below 3000 feet over the Y-12 plant. Also, the Federal Aviation Administration plans to reroute air traffic in the spring of 1993 on federal airway V16. However, the section of V16 which traverses the three plant sites and five adjoining facilities will not be altered. If this plan is implemented, the air traffic over the Oak Ridge facilities would not be affected significantly, and the probability of an aircraft crash as determined herein would be unchanged.

  9. Luminosity Function of Faint Globular Clusters in M87

    SciTech Connect (OSTI)

    Waters, Christopher Z.; Zepf, Stephen E.; Lauer, Tod R.; Baltz, Edward A.; Silk, Joseph; /Oxford U.

    2006-07-14

    We present the luminosity function to very faint magnitudes for the globular clusters in M87, based on a 30 orbit Hubble Space Telescope (HST) WFPC2 imaging program. The very deep images and corresponding improved false source rejection allow us to probe the mass function further beyond the turnover than has been done before. We compare our luminosity function to those that have been observed in the past, and confirm the similarity of the turnover luminosity between M87 and the Milky Way. We also find with high statistical significance that the M87 luminosity function is broader than that of the Milky Way. We discuss how determining the mass function of the cluster system to low masses can constrain theoretical models of the dynamical evolution of globular cluster systems. Our mass function is consistent with the dependence of mass loss on the initial cluster mass given by classical evaporation, and somewhat inconsistent with newer proposals that have a shallower mass dependence. In addition, the rate of mass loss is consistent with standard evaporation models, and not with the much higher rates proposed by some recent studies of very young cluster systems. We also find that the mass-size relation has very little slope, indicating that there is almost no increase in the size of a cluster with increasing mass.

  10. Structures of 38-atom gold-platinum nanoalloy clusters

    SciTech Connect (OSTI)

    Ong, Yee Pin; Yoon, Tiem Leong; Lim, Thong Leng

    2015-04-24

    Bimetallic nanoclusters, such as gold-platinum nanoclusters, are nanomaterials promising wide range of applications. We perform a numerical study of 38-atom gold-platinum nanoalloy clusters, Au{sub n}Pt{sub 38−n} (0 ≤ n ≤ 38), to elucidate the geometrical structures of these clusters. The lowest-energy structures of these bimetallic nanoclusters at the semi-empirical level are obtained via a global-minimum search algorithm known as parallel tempering multi-canonical basin hopping plus genetic algorithm (PTMBHGA), in which empirical Gupta many-body potential is used to describe the inter-atomic interactions among the constituent atoms. The structures of gold-platinum nanoalloy clusters are predicted to be core-shell segregated nanoclusters. Gold atoms are observed to preferentially occupy the surface of the clusters, while platinum atoms tend to occupy the core due to the slightly smaller atomic radius of platinum as compared to gold’s. The evolution of the geometrical structure of 38-atom Au-Pt clusters displays striking similarity with that of 38-atom Au-Cu nanoalloy clusters as reported in the literature.

  11. SHOCK HEATING OF THE MERGING GALAXY CLUSTER A521

    SciTech Connect (OSTI)

    Bourdin, H.; Mazzotta, P.; Markevitch, M.; Giacintucci, S.; Brunetti, G.

    2013-02-10

    A521 is an interacting galaxy cluster located at z = 0.247, hosting a low-frequency radio halo connected to an eastern radio relic. Previous Chandra observations hinted at the presence of an X-ray brightness edge at the position of the relic, which may be a shock front. We analyze a deep observation of A521 recently performed with XMM-Newton in order to probe the cluster structure up to the outermost regions covered by the radio emission. The cluster atmosphere exhibits various brightness and temperature anisotropies. In particular, two cluster cores appear to be separated by two cold fronts. We find two shock fronts, one that was suggested by Chandra and that is propagating to the east, and another to the southwestern cluster outskirt. The two main interacting clusters appear to be separated by a shock-heated region, which exhibits a spatial correlation with the radio halo. The outer edge of the radio relic coincides spatially with a shock front, suggesting that this shock is responsible for the generation of cosmic-ray electrons in the relic. The propagation direction and Mach number of the shock front derived from the gas density jump, M = 2.4 {+-} 0.2, are consistent with expectations from the radio spectral index, under the assumption of Fermi I acceleration mechanism.

  12. Electronic and magnetic properties of small rhodium clusters

    SciTech Connect (OSTI)

    Soon, Yee Yeen; Yoon, Tiem Leong; Lim, Thong Leng

    2015-04-24

    We report a theoretical study of the electronic and magnetic properties of rhodium-atomic clusters. The lowest energy structures at the semi-empirical level of rhodium clusters are first obtained from a novel global-minimum search algorithm, known as PTMBHGA, where Gupta potential is used to describe the atomic interaction among the rhodium atoms. The structures are then re-optimized at the density functional theory (DFT) level with exchange-correlation energy approximated by Perdew-Burke-Ernzerhof generalized gradient approximation. For the purpose of calculating the magnetic moment of a given cluster, we calculate the optimized structure as a function of the spin multiplicity within the DFT framework. The resultant magnetic moments with the lowest energies so obtained allow us to work out the magnetic moment as a function of cluster size. Rhodium atomic clusters are found to display a unique variation in the magnetic moment as the cluster size varies. However, Rh{sub 4} and Rh{sub 6} are found to be nonmagnetic. Electronic structures of the magnetic ground-state structures are also investigated within the DFT framework. The results are compared against those based on different theoretical approaches available in the literature.

  13. Agent-based method for distributed clustering of textual information

    DOE Patents [OSTI]

    Potok, Thomas E [Oak Ridge, TN; Reed, Joel W [Knoxville, TN; Elmore, Mark T [Oak Ridge, TN; Treadwell, Jim N [Louisville, TN

    2010-09-28

    A computer method and system for storing, retrieving and displaying information has a multiplexing agent (20) that calculates a new document vector (25) for a new document (21) to be added to the system and transmits the new document vector (25) to master cluster agents (22) and cluster agents (23) for evaluation. These agents (22, 23) perform the evaluation and return values upstream to the multiplexing agent (20) based on the similarity of the document to documents stored under their control. The multiplexing agent (20) then sends the document (21) and the document vector (25) to the master cluster agent (22), which then forwards it to a cluster agent (23) or creates a new cluster agent (23) to manage the document (21). The system also searches for stored documents according to a search query having at least one term and identifying the documents found in the search, and displays the documents in a clustering display (80) of similarity so as to indicate similarity of the documents to each other.

  14. STAR CLUSTER DISRUPTION IN THE STARBURST GALAXY MESSIER 82

    SciTech Connect (OSTI)

    Li, Shuo; Li, Chengyuan; De Grijs, Richard; Anders, Peter

    2015-01-01

    Using high-resolution, multiple-passband Hubble Space Telescope images spanning the entire optical/near-infrared wavelength range, we obtained a statistically complete U-band-selected sample of 846 extended star clusters across the disk of the nearby starburst galaxy M82. Based on a careful analysis of the clusters' spectral energy distributions, we determined their galaxy-wide age and mass distributions. The M82 clusters exhibit three clear peaks in their age distribution, thus defining relatively young, log (t yr{sup 1}) ? 7.5, intermediate-age, log (t yr{sup 1}) in [7.5, 8.5], and old samples, log (t yr{sup 1}) ? 8.5. Comparison of the completeness-corrected mass distributions offers a firm handle on the galaxy's star cluster disruption history. The most massive star clusters in the young and old samples are (almost) all concentrated in the most densely populated central region, while the intermediate-age sample's most massive clusters are more spatially dispersed, which may reflect the distribution of the highest-density gas throughout the galaxy's evolutionary history, combined with the solid-body nature of the galaxy's central region.

  15. Tech Area II: A history

    SciTech Connect (OSTI)

    Ullrich, R.

    1998-07-01

    This report documents the history of the major buildings in Sandia National Laboratories` Technical Area II. It was prepared in support of the Department of Energy`s compliance with Section 106 of the National Historic Preservation Act. Technical Area II was designed and constructed in 1948 specifically for the final assembly of the non-nuclear components of nuclear weapons, and was the primary site conducting such assembly until 1952. Both the architecture and location of the oldest buildings in the area reflect their original purpose. Assembly activities continued in Area II from 1952 to 1957, but the major responsibility for this work shifted to other sites in the Atomic Energy Commission`s integrated contractor complex. Gradually, additional buildings were constructed and the original buildings were modified. After 1960, the Area`s primary purpose was the research and testing of high-explosive components for nuclear weapons. In 1994, Sandia constructed new facilities for work on high-explosive components outside of the original Area II diamond-shaped parcel. Most of the buildings in the area are vacant and Sandia has no plans to use them. They are proposed for decontamination and demolition as funding becomes available.

  16. Why SRS Matters - L Area

    SciTech Connect (OSTI)

    Hunt, Paul

    2015-01-28

    A video series presenting an overview of the Savannah River Site's (SRS) mission and operations. Each episode features a specific area/operation and how it contributes to help make the world safer. This episode features L Area's mission and operations.

  17. Why SRS Matters - E Area

    SciTech Connect (OSTI)

    Howell, Steve; Mooneyhan, Verne; Tempel, Kevin; Bullington, Michele

    2015-03-09

    A video series presenting an overview of the Savannah River Site's (SRS) mission and operations. Each episode features a specific area/operation and how it contributes to help make the world safer. This episode features E Area's mission and operations.

  18. Why SRS Matters - F Area

    SciTech Connect (OSTI)

    Howell, Steve; Tadlock, Bill; Beeler, Dewitt; Gardner, Curt

    2015-02-17

    A video series presenting an overview of the Savannah River Site's (SRS) mission and operations. Each episode features a specific area/operation and how it contributes to help make the world safer. This episode features F Area's mission and operations.

  19. THE DISTANCE TO THE MASSIVE GALACTIC CLUSTER WESTERLUND 2 FROM A SPECTROSCOPIC AND HST PHOTOMETRIC STUDY

    SciTech Connect (OSTI)

    Vargas Alvarez, Carlos A.; Kobulnicky, Henry A.; Bradley, David R.; Kannappan, Sheila J.; Norris, Mark A.; Cool, Richard J.; Miller, Brendan P. E-mail: chipk@uwyo.edu E-mail: sheila@physics.unc.edu E-mail: rcool@obs.carnegiescience.edu

    2013-05-15

    We present a spectroscopic and photometric determination of the distance to the young Galactic open cluster Westerlund 2 using WFPC2 imaging from the Hubble Space Telescope (HST) and ground-based optical spectroscopy. HST imaging in the F336W, F439W, F555W, and F814W filters resolved many sources previously undetected in ground-based observations and yielded photometry for 1136 stars. We identified 15 new O-type stars, along with two probable binary systems, including MSP 188 (O3 + O5.5). We fit reddened spectral energy distributions based on the Padova isochrones to the photometric data to determine individual reddening parameters R{sub V} and A{sub V} for O-type stars in Wd2. We find average values (R{sub V} ) = 3.77 {+-} 0.09 and (A{sub V} ) = 6.51 {+-} 0.38 mag, which result in a smaller distance than most other spectroscopic and photometric studies. After a statistical distance correction accounting for close unresolved binaries (factor of 1.08), our spectroscopic and photometric data on 29 O-type stars yield that Westerlund 2 has a distance (d) = 4.16 {+-} 0.07 (random) +0.26 (systematic) kpc. The cluster's age remains poorly constrained, with an upper limit of 3 Myr. Finally, we report evidence of a faint mid-IR polycyclic aromatic hydrocarbon ring surrounding the well-known binary candidate MSP 18, which appears to lie at the center of a secondary stellar grouping within Westerlund 2.

  20. Parameter Analysis of the VPIN (Volume synchronized Probability of Informed Trading) Metric

    SciTech Connect (OSTI)

    Song, Jung Heon; Wu, Kesheng; Simon, Horst D.

    2014-03-01

    VPIN (Volume synchronized Probability of Informed trading) is a leading indicator of liquidity-induced volatility. It is best known for having produced a signal more than hours before the Flash Crash of 2010. On that day, the market saw the biggest one-day point decline in the Dow Jones Industrial Average, which culminated to the market value of $1 trillion disappearing, but only to recover those losses twenty minutes later (Lauricella 2010). The computation of VPIN requires the user to set up a handful of free parameters. The values of these parameters significantly affect the effectiveness of VPIN as measured by the false positive rate (FPR). An earlier publication reported that a brute-force search of simple parameter combinations yielded a number of parameter combinations with FPR of 7%. This work is a systematic attempt to find an optimal parameter set using an optimization package, NOMAD (Nonlinear Optimization by Mesh Adaptive Direct Search) by Audet, le digabel, and tribes (2009) and le digabel (2011). We have implemented a number of techniques to reduce the computation time with NOMAD. Tests show that we can reduce the FPR to only 2%. To better understand the parameter choices, we have conducted a series of sensitivity analysis via uncertainty quantification on the parameter spaces using UQTK (Uncertainty Quantification Toolkit). Results have shown dominance of 2 parameters in the computation of FPR. Using the outputs from NOMAD optimization and sensitivity analysis, We recommend A range of values for each of the free parameters that perform well on a large set of futures trading records.

  1. Realistic Probability Estimates For Destructive Overpressure Events In Heated Center Wing Tanks Of Commercial Jet Aircraft

    SciTech Connect (OSTI)

    Alvares, N; Lambert, H

    2007-02-07

    The Federal Aviation Administration (FAA) identified 17 accidents that may have resulted from fuel tank explosions on commercial aircraft from 1959 to 2001. Seven events involved JP 4 or JP 4/Jet A mixtures that are no longer used for commercial aircraft fuel. The remaining 10 events involved Jet A or Jet A1 fuels that are in current use by the commercial aircraft industry. Four fuel tank explosions occurred in center wing tanks (CWTs) where on-board appliances can potentially transfer heat to the tank. These tanks are designated as ''Heated Center Wing Tanks'' (HCWT). Since 1996, the FAA has significantly increased the rate at which it has mandated airworthiness directives (ADs) directed at elimination of ignition sources. This effort includes the adoption, in 2001, of Special Federal Aviation Regulation 88 of 14 CFR part 21 (SFAR 88 ''Fuel Tank System Fault Tolerance Evaluation Requirements''). This paper addresses SFAR 88 effectiveness in reducing HCWT ignition source probability. Our statistical analysis, relating the occurrence of both on-ground and in-flight HCWT explosions to the cumulative flight hours of commercial passenger aircraft containing HCWT's reveals that the best estimate of HCWT explosion rate is 1 explosion in 1.4 x 10{sup 8} flight hours. Based on an analysis of SFAR 88 by Sandia National Laboratories and our independent analysis, SFAR 88 reduces current risk of historical HCWT explosion by at least a factor of 10, thus meeting an FAA risk criteria of 1 accident in billion flight hours. This paper also surveys and analyzes parameters for Jet A fuel ignition in HCWT's. Because of the paucity of in-flight HCWT explosions, we conclude that the intersection of the parameters necessary and sufficient to result in an HCWT explosion with sufficient overpressure to rupture the HCWT is extremely rare.

  2. Probability of Future Observations Exceeding One-Sided, Normal, Upper Tolerance Limits

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

    Edwards, Timothy S.

    2014-10-29

    Normal tolerance limits are frequently used in dynamic environments specifications of aerospace systems as a method to account for aleatory variability in the environments. Upper tolerance limits, when used in this way, are computed from records of the environment and used to enforce conservatism in the specification by describing upper extreme values the environment may take in the future. Components and systems are designed to withstand these extreme loads to ensure they do not fail under normal use conditions. The degree of conservatism in the upper tolerance limits is controlled by specifying the coverage and confidence level (usually written inmore » “coverage/confidence” form). Moreover, in high-consequence systems it is common to specify tolerance limits at 95% or 99% coverage and confidence at the 50% or 90% level. Despite the ubiquity of upper tolerance limits in the aerospace community, analysts and decision-makers frequently misinterpret their meaning. The misinterpretation extends into the standards that govern much of the acceptance and qualification of commercial and government aerospace systems. As a result, the risk of a future observation of the environment exceeding the upper tolerance limit is sometimes significantly underestimated by decision makers. This note explains the meaning of upper tolerance limits and a related measure, the upper prediction limit. So, the objective of this work is to clarify the probability of exceeding these limits in flight so that decision-makers can better understand the risk associated with exceeding design and test levels during flight and balance the cost of design and development with that of mission failure.« less

  3. Probability density function method for variable-density pressure-gradient-driven turbulence and mixing

    SciTech Connect (OSTI)

    Bakosi, Jozsef; Ristorcelli, Raymond J

    2010-01-01

    Probability density function (PDF) methods are extended to variable-density pressure-gradient-driven turbulence. We apply the new method to compute the joint PDF of density and velocity in a non-premixed binary mixture of different-density molecularly mixing fluids under gravity. The full time-evolution of the joint PDF is captured in the highly non-equilibrium flow: starting from a quiescent state, transitioning to fully developed turbulence and finally dissipated by molecular diffusion. High-Atwood-number effects (as distinguished from the Boussinesq case) are accounted for: both hydrodynamic turbulence and material mixing are treated at arbitrary density ratios, with the specific volume, mass flux and all their correlations in closed form. An extension of the generalized Langevin model, originally developed for the Lagrangian fluid particle velocity in constant-density shear-driven turbulence, is constructed for variable-density pressure-gradient-driven flows. The persistent small-scale anisotropy, a fundamentally 'non-Kolmogorovian' feature of flows under external acceleration forces, is captured by a tensorial diffusion term based on the external body force. The material mixing model for the fluid density, an active scalar, is developed based on the beta distribution. The beta-PDF is shown to be capable of capturing the mixing asymmetry and that it can accurately represent the density through transition, in fully developed turbulence and in the decay process. The joint model for hydrodynamics and active material mixing yields a time-accurate evolution of the turbulent kinetic energy and Reynolds stress anisotropy without resorting to gradient diffusion hypotheses, and represents the mixing state by the density PDF itself, eliminating the need for dubious mixing measures. Direct numerical simulations of the homogeneous Rayleigh-Taylor instability are used for model validation.

  4. Peculiarities of high-overtone transition probabilities in carbon monoxide revealed by high-precision calculation

    SciTech Connect (OSTI)

    Medvedev, Emile S.; Meshkov, Vladimir V.; Stolyarov, Andrey V.

    2015-10-21

    In the recent work devoted to the calculation of the rovibrational line list of the CO molecule [G. Li et al., Astrophys. J., Suppl. Ser. 216, 15 (2015)], rigorous validation of the calculated parameters including intensities was carried out. In particular, the Normal Intensity Distribution Law (NIDL) [E. S. Medvedev, J. Chem. Phys. 137, 174307 (2012)] was employed for the validation purposes, and it was found that, in the original CO line list calculated for large changes of the vibrational quantum number up to Δn = 41, intensities with Δn > 11 were unphysical. Therefore, very high overtone transitions were removed from the published list in Li et al. Here, we show how this type of validation is carried out and prove that the quadruple precision is indispensably required to predict the reliable intensities using the conventional 32-bit computers. Based on these calculations, the NIDL is shown to hold up for the 0 → n transitions till the dissociation limit around n = 83, covering 45 orders of magnitude in the intensity. The low-intensity 0 → n transition predicted in the work of Medvedev [Determination of a new molecular constant for diatomic systems. Normal intensity distribution law for overtone spectra of diatomic and polyatomic molecules and anomalies in overtone absorption spectra of diatomic molecules, Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka, 1984] at n = 5 is confirmed, and two additional “abnormal” intensities are found at n = 14 and 23. Criteria for the appearance of such “anomalies” are formulated. The results could be useful to revise the high-overtone molecular transition probabilities provided in spectroscopic databases.

  5. AREA

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

    or if they need to add this to their audit they have performed yearly by a public accounting firm. 316 audits are essentially A-133 audits for for-profit entities. They DO...

  6. AREA

    Office of Environmental Management (EM)

    DCAA would never agree to perform A-133 or our 316 audits. They don't do A-133 audits for DOD awardees. The purpose of the audits are different, look at different things and in the ...

  7. R-Area Reactor 1993 annual groundwater monitoring report

    SciTech Connect (OSTI)

    Not Available

    1994-09-01

    Groundwater was sampled and analyzed during 1993 from wells monitoring the following locations in R Area: Well cluster P20 east of R Area (one well each in the water table and the McBean formation), the R-Area Acid/Caustic Basin (the four water-table wells of the RAC series), the R-Area Ash Basin/Coal Pile (one well of the RCP series in the Congaree formation and one in the water table), the R-Area Disassembly Basin (the three water-table wells of the RDB series), the R-Area Burning/Rubble Pits (the four water-table wells of the RRP series), and the R-Area Seepage Basins (numerous water-table wells in the RSA, RSB, RSC, RSD, RSE, and RSF series). Lead was the only constituent detected above its 50{mu}g/L standard in any but the seepage basin wells; it exceeded that level in one B well and in 23 of the seepage basin wells. Cadmium exceeded its drinking water standard (DWS) in 30 of the seepage basin wells, as did mercury in 10. Nitrate-nitrite was above DWS once each in two seepage basin wells. Tritium was above DWS in six seepage basin wells, as was gross alpha activity in 22. Nonvolatile beta exceeded its screening standard in 29 wells. Extensive radionuclide analyses were requested during 1993 for the RCP series and most of the seepage basin wells. Strontium-90 in eight wells was the only specific radionuclide other than tritium detected above DWS; it appeared about one-half of the nonvolatile beta activity in those wells.

  8. Technical evaluation: 300 Area steam line valve accident

    SciTech Connect (OSTI)

    Not Available

    1993-08-01

    On June 7, 1993, a journeyman power operator (JPO) was severely burned and later died as a result of the failure of a 6-in. valve that occurred when he attempted to open main steam supply (MSS) valve MSS-25 in the U-3 valve pit. The pit is located northwest of Building 331 in the 300 Area of the Hanford Site. Figure 1-1 shows a layout of the 300 Area steam piping system including the U-3 steam valve pit. Figure 1-2 shows a cutaway view of the approximately 10- by 13- by 16-ft-high valve pit with its various steam valves and connecting piping. Valve MSS-25, an 8-in. valve, is located at the bottom of the pit. The failed 6-in. valve was located at the top of the pit where it branched from the upper portion of the 8-in. line at the 8- by 8- by 6-in. tee and was then ``blanked off`` with a blind flange. The purpose of this technical evaluation was to determine the cause of the accident that led to the failure of the 6-in. valve. The probable cause for the 6-in. valve failure was determined by visual, nondestructive, and destructive examination of the failed valve and by metallurgical analysis of the fractured region of the valve. The cause of the accident was ultimately identified by correlating the observed failure mode to the most probable physical phenomenon. Thermal-hydraulic analyses, component stress analyses, and tests were performed to verify that the probable physical phenomenon could be reasonably expected to produce the failure in the valve that was observed.

  9. Effect of Graphene with Nanopores on Metal Clusters

    SciTech Connect (OSTI)

    Zhou, Hu; Chen, Xianlang; Wang, Lei; Zhong, Xing; Zhuang, Guilin; Li, Xiaonian; Mei, Donghai; Wang, Jianguo

    2015-10-07

    Porous graphene, which is a novel type of defective graphene, shows excellent potential as a support material for metal clusters. In this work, the stability and electronic structures of metal clusters (Pd, Ir, Rh) supported on pristine graphene and graphene with different sizes of nanopore were investigated by first-principle density functional theory (DFT) calculations. Thereafter, CO adsorption and oxidation reaction on the Pd-graphene system were chosen to evaluate its catalytic performance. Graphene with nanopore can strongly stabilize the metal clusters and cause a substantial downshift of the d-band center of the metal clusters, thus decreasing CO adsorption. All binding energies, d-band centers, and adsorption energies show a linear change with the size of the nanopore: a bigger size of nanopore corresponds to a stronger metal clusters bond to the graphene, lower downshift of the d-band center, and weaker CO adsorption. By using a suitable size nanopore, supported Pd clusters on the graphene will have similar CO and O2 adsorption ability, thus leading to superior CO tolerance. The DFT calculated reaction energy barriers show that graphene with nanopore is a superior catalyst for CO oxidation reaction. These properties can play an important role in instructing graphene-supported metal catalyst preparation to prevent the diffusion or agglomeration of metal clusters and enhance catalytic performance. This work was supported by National Basic Research Program of China (973Program) (2013CB733501), the National Natural Science Foundation of China (NSFC-21176221, 21136001, 21101137, 21306169, and 91334013). D. Mei acknowledges the support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. Computing time was granted by the grand challenge of computational

  10. Identification of Patient Benefit From Proton Therapy for Advanced Head and Neck Cancer Patients Based on Individual and Subgroup Normal Tissue Complication Probability Analysis

    SciTech Connect (OSTI)

    Jakobi, Annika; Bandurska-Luque, Anna; Stützer, Kristin; Haase, Robert; Löck, Steffen; Wack, Linda-Jacqueline; Mönnich, David; Thorwarth, Daniela; and others

    2015-08-01

    Purpose: The purpose of this study was to determine, by treatment plan comparison along with normal tissue complication probability (NTCP) modeling, whether a subpopulation of patients with head and neck squamous cell carcinoma (HNSCC) could be identified that would gain substantial benefit from proton therapy in terms of NTCP. Methods and Materials: For 45 HNSCC patients, intensity modulated radiation therapy (IMRT) was compared to intensity modulated proton therapy (IMPT). Physical dose distributions were evaluated as well as the resulting NTCP values, using modern models for acute mucositis, xerostomia, aspiration, dysphagia, laryngeal edema, and trismus. Patient subgroups were defined based on primary tumor location. Results: Generally, IMPT reduced the NTCP values while keeping similar target coverage for all patients. Subgroup analyses revealed a higher individual reduction of swallowing-related side effects by IMPT for patients with tumors in the upper head and neck area, whereas the risk reduction of acute mucositis was more pronounced in patients with tumors in the larynx region. More patients with tumors in the upper head and neck area had a reduction in NTCP of more than 10%. Conclusions: Subgrouping can help to identify patients who may benefit more than others from the use of IMPT and, thus, can be a useful tool for a preselection of patients in the clinic where there are limited PT resources. Because the individual benefit differs within a subgroup, the relative merits should additionally be evaluated by individual treatment plan comparisons.

  11. Vital area analysis using sets

    SciTech Connect (OSTI)

    Stack, D.W.; Francis, K.A.

    1980-05-01

    This report describes the use of the Set Equation Transformation System (SETS) for vital area analysis. Several concepts are introduced which enable the analyst to construct more efficient SETS user programs to perform vital area analysis. The advantages of performing the transformation of variables without first determining the minimal cut sets of the fault tree are discussed. A ''bottom-up'' approach to solving a fault tree is presented. The techniques described for vital area analysis are also suitable and efficient for many kinds of common cause analysis.

  12. SPACE PROPULSION SYSTEM PHASED-MISSION PROBABILITY ANALYSIS USING CONVENTIONAL PRA METHODS

    SciTech Connect (OSTI)

    Curtis Smith; James Knudsen

    2006-05-01

    As part of a series of papers on the topic of advance probabilistic methods, a benchmark phased-mission problem has been suggested. This problem consists of modeling a space mission using an ion propulsion system, where the mission consists of seven mission phases. The mission requires that the propulsion operate for several phases, where the configuration changes as a function of phase. The ion propulsion system itself consists of five thruster assemblies and a single propellant supply, where each thruster assembly has one propulsion power unit and two ion engines. In this paper, we evaluate the probability of mission failure using the conventional methodology of event tree/fault tree analysis. The event tree and fault trees are developed and analyzed using Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE). While the benchmark problem is nominally a "dynamic" problem, in our analysis the mission phases are modeled in a single event tree to show the progression from one phase to the next. The propulsion system is modeled in fault trees to account for the operation; or in this case, the failure of the system. Specifically, the propulsion system is decomposed into each of the five thruster assemblies and fed into the appropriate N-out-of-M gate to evaluate mission failure. A separate fault tree for the propulsion system is developed to account for the different success criteria of each mission phase. Common-cause failure modeling is treated using traditional (i.e., parametrically) methods. As part of this paper, we discuss the overall results in addition to the positive and negative aspects of modeling dynamic situations with non-dynamic modeling techniques. One insight from the use of this conventional method for analyzing the benchmark problem is that it requires significant manual manipulation to the fault trees and how they are linked into the event tree. The conventional method also requires editing the resultant cut sets to

  13. SEARCHING FOR COOLING SIGNATURES IN STRONG LENSING GALAXY CLUSTERS: EVIDENCE AGAINST BARYONS SHAPING THE MATTER DISTRIBUTION IN CLUSTER CORES

    SciTech Connect (OSTI)

    Blanchard, Peter K.; Bayliss, Matthew B.; McDonald, Michael; Dahle, Hakon; Gladders, Michael D.; Sharon, Keren; Mushotzky, Richard

    2013-07-20

    The process by which the mass density profile of certain galaxy clusters becomes centrally concentrated enough to produce high strong lensing (SL) cross-sections is not well understood. It has been suggested that the baryonic condensation of the intracluster medium (ICM) due to cooling may drag dark matter to the cores and thus steepen the profile. In this work, we search for evidence of ongoing ICM cooling in the first large, well-defined sample of SL selected galaxy clusters in the range 0.1 < z < 0.6. Based on known correlations between the ICM cooling rate and both optical emission line luminosity and star formation, we measure, for a sample of 89 SL clusters, the fraction of clusters that have [O II]{lambda}{lambda}3727 emission in their brightest cluster galaxy (BCG). We find that the fraction of line-emitting BCGs is constant as a function of redshift for z > 0.2 and shows no statistically significant deviation from the total cluster population. Specific star formation rates, as traced by the strength of the 4000 A break, D{sub 4000}, are also consistent with the general cluster population. Finally, we use optical imaging of the SL clusters to measure the angular separation, R{sub arc}, between the arc and the center of mass of each lensing cluster in our sample and test for evidence of changing [O II] emission and D{sub 4000} as a function of R{sub arc}, a proxy observable for SL cross-sections. D{sub 4000} is constant with all values of R{sub arc}, and the [O II] emission fractions show no dependence on R{sub arc} for R{sub arc} > 10'' and only very marginal evidence of increased weak [O II] emission for systems with R{sub arc} < 10''. These results argue against the ability of baryonic cooling associated with cool core activity in the cores of galaxy clusters to strongly modify the underlying dark matter potential, leading to an increase in SL cross-sections.

  14. Reference air kerma and kerma-area product as estimators of peak skin dose for fluoroscopically guided interventions

    SciTech Connect (OSTI)

    Kwon, Deukwoo; Little, Mark P.; Miller, Donald L.

    2011-07-15

    Purpose: To determine more accurate regression formulas for estimating peak skin dose (PSD) from reference air kerma (RAK) or kerma-area product (KAP). Methods: After grouping of the data from 21 procedures into 13 clinically similar groups, assessments were made of optimal clustering using the Bayesian information criterion to obtain the optimal linear regressions of (log-transformed) PSD vs RAK, PSD vs KAP, and PSD vs RAK and KAP. Results: Three clusters of clinical groups were optimal in regression of PSD vs RAK, seven clusters of clinical groups were optimal in regression of PSD vs KAP, and six clusters of clinical groups were optimal in regression of PSD vs RAK and KAP. Prediction of PSD using both RAK and KAP is significantly better than prediction of PSD with either RAK or KAP alone. The regression of PSD vs RAK provided better predictions of PSD than the regression of PSD vs KAP. The partial-pooling (clustered) method yields smaller mean squared errors compared with the complete-pooling method.Conclusion: PSD distributions for interventional radiology procedures are log-normal. Estimates of PSD derived from RAK and KAP jointly are most accurate, followed closely by estimates derived from RAK alone. Estimates of PSD derived from KAP alone are the least accurate. Using a stochastic search approach, it is possible to cluster together certain dissimilar types of procedures to minimize the total error sum of squares.

  15. Borehole Completion and Conceptual Hydrogeologic Model for the IFRC Well Field, 300 Area, Hanford Site

    SciTech Connect (OSTI)

    Bjornstad, Bruce N.; Horner, Jacob A.; Vermeul, Vincent R.; Lanigan, David C.; Thorne, Paul D.

    2009-04-20

    A tight cluster of 35 new wells was installed over a former waste site, the South Process Pond (316-1 waste site), in the Hanford Site 300 Area in summer 2008. This report documents the details of the drilling, sampling, and well construction for the new array and presents a summary of the site hydrogeology based on the results of drilling and preliminary geophysical logging.

  16. Manhattan Project: Tech Area Gallery

    Office of Scientific and Technical Information (OSTI)

    All of the photographs below are of the "Tech Area" at Los Alamos during or shortly after the wartime years. If you have a fast internet connection, you may wish to click here for ...

  17. Fire in a contaminated area

    SciTech Connect (OSTI)

    Ryan, G.W., Westinghouse Hanford

    1996-08-28

    This document supports the development and presentation of the following accident scenario in the TWRS Final Safety Analysis Report: Fire in Contaminated Area. The calculations needed to quantify the risk associated with this accident scenario are included within.

  18. Progress Update: M Area Closure

    ScienceCinema (OSTI)

    Cody, Tom

    2012-06-14

    A progress update of the Recovery Act at work at the Savannah River Site. The celebration of the first area cleanup completion with the help of the Recovery Act.

  19. CENTRAL NEVPJJA SUPPLEMENTAL TEST AREA

    Office of Legacy Management (LM)

    CENTRAL NEVPJJA SUPPLEMENTAL TEST AREA ,FACILITY RECORDS 1970 UNITED STATES ATOMIC ENERGY ... Prepared By Holmes & Narver. Inc. On-Continent Test Division P.O. Box 14340 Las Vegas, ...

  20. Security Area Vouching and Piggybacking

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

    2000-06-05

    Establishes requirements for the Department of Energy (DOE) Security Area practice of "vouching" or "piggybacking" access by personnel. DOE N 251.40, dated 5-3-01, extends this directive until 12-31-01.

  1. Manhattan Project: Tech Area Gallery

    Office of Scientific and Technical Information (OSTI)

    All of the photographs below are of the "Tech Area" at Los Alamos during or shortly after the wartime years. If this page is taking a long time to load, click here for a photo ...

  2. Focus Areas | Department of Energy

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

    Focus Areas Focus Areas Safety With this focus on cleanup completion and risk reducing results, safety still remains the utmost priority. EM will continue to maintain and demand the highest safety performance. All workers deserve to go home as healthy as they were when they came to the job in the morning. There is no schedule or milestone worth any injury to the work force. Project Management EM is increasing its concentration on project management to improve its overall performance toward

  3. Variable area fuel cell cooling

    DOE Patents [OSTI]

    Kothmann, Richard E.

    1982-01-01

    A fuel cell arrangement having cooling fluid flow passages which vary in surface area from the inlet to the outlet of the passages. A smaller surface area is provided at the passage inlet, which increases toward the passage outlet, so as to provide more uniform cooling of the entire fuel cell. The cooling passages can also be spaced from one another in an uneven fashion.

  4. Carlsbad Area Office Executive Summary

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

    June 1998 Carlsbad Area Office Executive Summary The mission of the Carlsbad Area Office (CAO) is to protect human health and the environment by opening and operating the Waste Isolation Pilot Plant (WIPP) for safe disposal of transuranic (TRU) waste and by establishing an effective system for management of TRU waste from generation to disposal. It includes personnel assigned to CAO, WIPP site operations, transportation, and other activities associated with the National TRU Program (NTP). The

  5. Monoxides of small terbium clusters: A density functional theory investigation

    SciTech Connect (OSTI)

    Zhang, G. L.; Yuan, H. K. Chen, H.; Kuang, A. L.; Li, Y.; Wang, J. Z.; Chen, J.

    2014-12-28

    To investigate the effect of oxygen atom on the geometrical structures, electronic, and magnetic properties of small terbium clusters, we carried out the first-principles calculations on Tb{sub n}O (n = 1-14) clusters. The capping of an oxygen atom on one trigonal-facet of Tb{sub n} structures is always favored energetically, which can significantly improve the structural stability. The far-infrared vibrational spectroscopies are found to be different from those of corresponding bare clusters, providing a distinct signal to detect the characteristic structures of Tb{sub n}O clusters. The primary effect of oxygen atom on magnetic properties is to change the magnetic orderings among Tb atoms and to reduce small of local magnetic moments of the O-coordinated Tb atoms, both of which serve as the key reasons for the experimental magnetic evolution of an oscillating behavior. These calculations are consistent with, and help to account for, the experimentally observed magnetic properties of monoxide Tb{sub n}O clusters [C. N. Van Dijk et al., J. Appl. Phys. 107, 09B526 (2010)].

  6. DISRUPTION OF STAR CLUSTERS IN THE INTERACTING ANTENNAE GALAXIES

    SciTech Connect (OSTI)

    Karl, Simon J.; Naab, Thorsten; Fall, S. Michael E-mail: naab@mpa-garching.mpg.de

    2011-06-10

    We re-examine the age distribution of star clusters in the Antennae in the context of N-body+hydrodynamical simulations of these interacting galaxies. All of the simulations that account for the observed morphology and other properties of the Antennae have star formation rates that vary relatively slowly with time, by factors of only 1.3-2.5 in the past 10{sup 8} yr. In contrast, the observed age distribution of the clusters declines approximately as a power law, dN/d{tau}{proportional_to}{tau}{sup {gamma}} with {gamma} = -1.0, for ages 10{sup 6} yr {approx}< {tau} {approx}< 10{sup 9} yr. These two facts can only be reconciled if the clusters are disrupted progressively for at least {approx}10{sup 8} yr and possibly {approx}10{sup 9} yr. When we combine the simulated formation rates with a power-law model, f{sub surv}{proportional_to}{tau}{sup {delta}}, for the fraction of clusters that survive to each age {tau}, we match the observed age distribution with exponents in the range -0.9 {approx}< {delta} {approx}< -0.6 (with a slightly different {delta} for each simulation). The similarity between {delta} and {gamma} indicates that dN/d{tau} is shaped mainly by the disruption of clusters rather than variations in their formation rate. Thus, the situation in the interacting Antennae resembles that in relatively quiescent galaxies such as the Milky Way and the Magellanic Clouds.

  7. Towards a Real-Time Cluster Computing Infrastructure

    SciTech Connect (OSTI)

    Hui, Peter SY; Chikkagoudar, Satish; Chavarría-Miranda, Daniel; Johnston, Mark R.

    2011-11-01

    Real-time computing has traditionally been considered largely in the context of single-processor and embedded systems, and indeed, the terms real-time computing, embedded systems, and control systems are often mentioned in closely related contexts. However, real-time computing in the context of multinode systems, specifically high-performance, cluster-computing systems, remains relatively unexplored, largely due to the fact that until now, there has not been a need for such an environment. In this paper, we motivate the need for a cluster computing infrastructure capable of supporting computation over large datasets in real-time. Our motivating example is an analytical framework to support the next generation North American power grid, which is growing both in size and complexity. With streaming sensor data in the future power grid potentially reaching rates on the order of terabytes per day, the task of analyzing this data subject to real-time guarantees becomes a daunting task which will require the power of high-performance cluster computing capable of functioning under real-time constraints. One specific challenge that such an environment presents is the need for real-time networked communication between cluster nodes. In this paper, we discuss the need for real-time high-performance cluster computation, along with our work-in-progress towards an infrastructure which will ultimately enable such an environment.

  8. The Hyperion Project: Partnership for an Advaned Technology Cluster Testbed

    SciTech Connect (OSTI)

    Seager, M; Leininger, M

    2008-04-28

    The Hyperion project offers a unique opportunity to participate in a community-driven testing and development resource at a scale beyond what can be accomplished by one entity alone. Hyperion is a new strategic technology partnership intended to support the member-driven development and testing at scale. This partnership will allow commodity clusters to scale up to meet the growing demands of customers multi-core petascale simulation environments. Hyperion will tightly couple together the outstanding research and development capabilities of Lawrence Livermore National Laboratory with leading technology companies, including Cisco, Data Direct Networks, Dell, Intel, LSI, Mellanox, Qlogic, RedHat, SuperMicro and Sun. The end goal of this project is to revolutionize cluster computing in fundamental ways by providing the critical software and hardware components for a highly scalable simulation environment. This environment will include support for high performance networking, parallel file systems, operating system, and cluster management. This goal will be achieved by building a scalable technology cluster testbed that will be fully dedicated to the partners and provide: (1) A scalable development testing and benchmarking environment for critical enabling Linux cluster technologies; (2) An evaluation testbed for new hardware and software technologies; and (3) A vehicle for forming long term collaborations.

  9. THE STRUCTURAL EVOLUTION OF FORMING AND EARLY STAGE STAR CLUSTERS

    SciTech Connect (OSTI)

    Jaehnig, Karl O.; Da Rio, Nicola; Tan, Jonathan C. E-mail: ndario@ufl.edu

    2015-01-10

    We study the degree of angular substructure in the stellar position distribution of young members of Galactic star-forming regions, looking for correlations with distance from cluster center, surface number density of stars, and local dynamical age. To this end we adopt the catalog of members in 18 young (?1-3Myr) clusters from the Massive Young Star-Forming Complex Study in Infrared and X-ray Survey and the statistical analysis of the angular dispersion parameter, ?{sub ADP,} {sub N}. We find statistically significant correlation between ?{sub ADP,} {sub N} and physical projected distance from the center of the clusters, with the centers appearing smoother than the outskirts, consistent with more rapid dynamical processing on local dynamical, free-fall or orbital timescales. Similarly, smoother distributions are seen in regions of higher surface density, or older dynamical ages. These results indicate that dynamical processing that erases substructure is already well-advanced in young, sometimes still-forming, clusters. Such observations of the dissipation of substructure have the potential to constrain theoretical models of the dynamical evolution of young and forming clusters.

  10. ASSEMBLY OF THE RED SEQUENCE IN INFRARED-SELECTED GALAXY CLUSTERS FROM THE IRAC SHALLOW CLUSTER SURVEY

    SciTech Connect (OSTI)

    Snyder, Gregory F.; Brodwin, Mark; Mancone, Conor M.; Gonzalez, Anthony H.; Zeimann, Gregory R.; Stanford, S. A.; Stern, Daniel; Eisenhardt, Peter R. M.; Brown, Michael J. I.; Dey, Arjun; Jannuzi, Buell; Perlmutter, Saul

    2012-09-10

    We present results for the assembly and star formation histories (SFHs) of massive ({approx}L*) red sequence galaxies (RSGs) in 11 spectroscopically confirmed, infrared-selected galaxy clusters at 1.0 < z < 1.5, the precursors to present-day massive clusters with M {approx} 10{sup 15} M{sub Sun }. Using rest-frame optical photometry, we investigate evolution in the color and scatter of the RSG population, comparing with models of possible SFHs. In contrast to studies of central cluster galaxies at lower redshift (z < 1), these data are clearly inconsistent with the continued evolution of stars formed and assembled primarily at a single, much earlier time. Specifically, we find that the colors of massive cluster galaxies at z Almost-Equal-To 1.5 imply that the bulk of star formation occurred at z {approx} 3, whereas by z Almost-Equal-To 1 their colors imply formation at z {approx} 2; therefore these galaxies exhibit approximately the same luminosity-weighted stellar age at 1 < z < 1.5. This likely reflects star formation that occurs over an extended period, the effects of significant progenitor bias, or both. Our results generally indicate that massive cluster galaxy populations began forming a significant mass of stars at z {approx}> 4, contained some red spheroids by z Almost-Equal-To 1.5, and were actively assembling much of their final mass during 1 < z < 2 in the form of younger stars. Qualitatively, the slopes of the cluster color-magnitude relations are consistent with no significant evolution relative to local clusters.

  11. Research Subject Areas for IGPPS Proposals

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

    Research Subject Areas Research Subject Areas for IGPPS Proposals High quality, cutting-edge science in the areas of astrophysics, space physics, solid planetary geoscience, and...

  12. Java - Dieng Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Java - Dieng Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Java - Dieng Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3...

  13. Java - Kamojang Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Java - Kamojang Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Java - Kamojang Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3...

  14. Java - Darajat Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Java - Darajat Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Java - Darajat Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3...

  15. Great Basin Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Great Basin Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Great Basin Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3...

  16. Sacramento Area Technology Alliance | Open Energy Information

    Open Energy Info (EERE)

    Sacramento Area Technology Alliance Jump to: navigation, search Logo: Sacramento Area Technology Alliance Name: Sacramento Area Technology Alliance Address: 5022 Bailey Loop Place:...

  17. Wild Rose Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Wild Rose Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Wild Rose Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory...

  18. Butte Springs Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Butte Springs Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Butte Springs Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3...

  19. Chocolate Mountains Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Chocolate Mountains Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Chocolate Mountains Geothermal Area Contents 1 Area Overview 2 History and...

  20. Mcgee Mountain Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Mcgee Mountain Geothermal Area (Redirected from Mcgee Mountain Area) Redirect page Jump to: navigation, search REDIRECT McGee Mountain Geothermal Area Retrieved from "http:...

  1. Alum Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Alum Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Alum Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and...

  2. Aurora Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Aurora Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Aurora Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and...

  3. Berln Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Berln Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Berln Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and...

  4. Stillwater Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Stillwater Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Stillwater Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3...

  5. Krafla Geothermal Area | Open Energy Information

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    Krafla Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Krafla Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and...

  6. Salt Wells Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Salt Wells Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Salt Wells Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 2.1 Salt...

  7. Rye Patch Geothermal Area | Open Energy Information

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  8. Amedee Geothermal Area | Open Energy Information

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  9. Miravalles Geothermal Area | Open Energy Information

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  10. Oita Geothermal Area | Open Energy Information

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  11. Cove Fort Geothermal Area | Open Energy Information

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  12. Geysers Geothermal Area | Open Energy Information

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  13. Larderello Geothermal Area | Open Energy Information

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  14. Dixie Valley Geothermal Area | Open Energy Information

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    Field Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Dixie Valley Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 2.1 U.S. Department...

  15. Dixie Valley Geothermal Area | Open Energy Information

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    Dixie Valley Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Dixie Valley Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 2.1...

  16. Geothermal resource area 11, Clark County area development plan

    SciTech Connect (OSTI)

    Pugsley, M.

    1981-01-01

    Geothermal Resource Area 11 includes all of the land in Clark County, Nevada. Within this area are nine geothermal anomalies: Moapa Area, Las Vegas Valley, Black Canyon, Virgin River Narrows, Roger's Springs, Indian Springs, White Rock Springs, Brown's Spring, and Ash Creek Spring. All of the geothermal resources in Clark County have relatively low temperatures. The highest recorded temperature is 145{sup 0}F at Black Canyon. The temperatures of the other resources range from 70 to 90{sup 0}F. Because of the low temperature of the resources and, for the most part, the distance of the resources from any population base, the potential for the development of the resources are considered to be somewhat limited.

  17. Calculation of Fire Severity Factors and Fire Non-Suppression Probabilities For A DOE Facility Fire PRA

    SciTech Connect (OSTI)

    Tom Elicson; Bentley Harwood; Jim Bouchard; Heather Lucek

    2011-03-01

    Over a 12 month period, a fire PRA was developed for a DOE facility using the NUREG/CR-6850 EPRI/NRC fire PRA methodology. The fire PRA modeling included calculation of fire severity factors (SFs) and fire non-suppression probabilities (PNS) for each safe shutdown (SSD) component considered in the fire PRA model. The SFs were developed by performing detailed fire modeling through a combination of CFAST fire zone model calculations and Latin Hypercube Sampling (LHS). Component damage times and automatic fire suppression system actuation times calculated in the CFAST LHS analyses were then input to a time-dependent model of fire non-suppression probability. The fire non-suppression probability model is based on the modeling approach outlined in NUREG/CR-6850 and is supplemented with plant specific data. This paper presents the methodology used in the DOE facility fire PRA for modeling fire-induced SSD component failures and includes discussions of modeling techniques for: • Development of time-dependent fire heat release rate profiles (required as input to CFAST), • Calculation of fire severity factors based on CFAST detailed fire modeling, and • Calculation of fire non-suppression probabilities.

  18. THREE DISCRETE GROUPS WITH HOMOGENEOUS CHEMISTRY ALONG THE RED GIANT BRANCH IN THE GLOBULAR CLUSTER NGC2808

    SciTech Connect (OSTI)

    Carretta, E.

    2014-11-10

    We present the homogeneous reanalysis of Mg and Al abundances from high resolution UVES/FLAMES spectra for 31 red giants in the globular cluster NGC2808. We found a well defined Mg-Al anticorrelation reaching a regime of subsolar Mg abundance ratios, with a spread of about 1.4dex in [Al/Fe]. The main result from the improved statistics of our sample is that the distribution of stars is not continuous along the anticorrelation because they are neatly clustered into three distinct clumps, each with different chemical compositions. One group (P) shows a primordial composition of field stars of similar metallicity, and the other two (I and E) have increasing abundances of Al and decreasing abundances of Mg. The fraction of stars we found in the three components (P: 68%, I: 19%, E: 13%) is in excellent agreement with the ratios computed for the three distinct main sequences in NGC2808: for the first time there is a clear correspondence between discrete photometric sequences of dwarfs and distinct groups of giants with homogeneous chemistry. The composition of the I group cannot be reproduced by mixing of matter with extreme processing in hot H-burning and gas with pristine, unprocessed composition, as also found in the recent analysis of three discrete groups in NGC6752. This finding suggests that different classes of polluters were probably at work in NGC2808 as well.

  19. Script identification from images using cluster-based templates

    DOE Patents [OSTI]

    Hochberg, J.G.; Kelly, P.M.; Thomas, T.R.

    1998-12-01

    A computer-implemented method identifies a script used to create a document. A set of training documents for each script to be identified is scanned into the computer to store a series of exemplary images representing each script. Pixels forming the exemplary images are electronically processed to define a set of textual symbols corresponding to the exemplary images. Each textual symbol is assigned to a cluster of textual symbols that most closely represents the textual symbol. The cluster of textual symbols is processed to form a representative electronic template for each cluster. A document having a script to be identified is scanned into the computer to form one or more document images representing the script to be identified. Pixels forming the document images are electronically processed to define a set of document textual symbols corresponding to the document images. The set of document textual symbols is compared to the electronic templates to identify the script. 17 figs.

  20. Script identification from images using cluster-based templates

    DOE Patents [OSTI]

    Hochberg, Judith G.; Kelly, Patrick M.; Thomas, Timothy R.

    1998-01-01

    A computer-implemented method identifies a script used to create a document. A set of training documents for each script to be identified is scanned into the computer to store a series of exemplary images representing each script. Pixels forming the exemplary images are electronically processed to define a set of textual symbols corresponding to the exemplary images. Each textual symbol is assigned to a cluster of textual symbols that most closely represents the textual symbol. The cluster of textual symbols is processed to form a representative electronic template for each cluster. A document having a script to be identified is scanned into the computer to form one or more document images representing the script to be identified. Pixels forming the document images are electronically processed to define a set of document textual symbols corresponding to the document images. The set of document textual symbols is compared to the electronic templates to identify the script.

  1. Apparatus for simultaneously disreefing a centrally reefed clustered parachute system

    DOE Patents [OSTI]

    Johnson, Donald W.

    1988-01-01

    A single multi-line cutter is connected to each of a cluster of parachutes by a separate short tether line that holds the parachutes, initially reefed by closed loop reefing lines, close to one another. The closed loop reefing lines and tether lines, one from each parachute, are disposed within the cutter to be simultaneously cut by its actuation when a central line attached between the payload and the cutter is stretched upon deployment of the cluster. A pyrotechnic or electronic time delay may be included in the cutter to delay the actual simultaneous cutting of all lines until the clustered parachutes attain a measure of stability prior to being disreefed. A second set of reefing lines and second tether lines may be provided for each parachute, to enable a two-stage, separately timed, step-by-step disreefing.

  2. Intermediate-age globular clusters in four galaxy merger remnants

    SciTech Connect (OSTI)

    Trancho, Gelys; Miller, Bryan W.; Schweizer, François; Burdett, Daniel P.; Palamara, David

    2014-08-01

    We present the results of combining Hubble Space Telescope optical photometry with ground-based K{sub s} -band photometry from the Gemini imagers NIRI and FLAMINGOS-I to study the globular cluster (GC) populations in four early-type galaxies that are candidate remnants of recent mergers (NGC 1700, NGC 2865, NGC 4382, and NGC 7727). These galaxies were chosen based on their blue colors and fine structure, such as shells and ripples that are indicative of past interactions. We fit the combined VIK{sub s} GC data with simple toy models of mixed cluster populations that contain three subpopulations of different age and metallicity. The fits, done via chi-squared mapping of the parameter space, yield clear evidence for the presence of intermediate-age clusters in each galaxy. We find that the ages of ∼1-2 Gyr for these GC subpopulations are consistent with the previously estimated merger ages for the host galaxies.

  3. Apparatus for simultaneously disreefing a centrally reefed clustered parachute system

    DOE Patents [OSTI]

    Johnson, D.W.

    1988-06-21

    A single multi-line cutter is connected to each of a cluster of parachutes by a separate short tether line that holds the parachutes, initially reefed by closed loop reefing lines, close to one another. The closed loop reefing lines and tether lines, one from each parachute, are disposed within the cutter to be simultaneously cut by its actuation when a central line attached between the payload and the cutter is stretched upon deployment of the cluster. A pyrotechnic or electronic time delay may be included in the cutter to delay the actual simultaneous cutting of all lines until the clustered parachutes attain a measure of stability prior to being disreefed. A second set of reefing lines and second tether lines may be provided for each parachute, to enable a two-stage, separately timed, step-by-step disreefing. 13 figs.

  4. Magnetic Moment Enhancement for Mn7 Cluster on Graphene

    SciTech Connect (OSTI)

    Liu, Xiaojie; Wang, Cai-Zhuang; Lin, Hai-Qing; Ho, Kai-Ming

    2014-08-21

    Mn7 cluster on graphene with different structural motifs and magnetic orders are investigated systematically by first-principles calculations. The calculations show that Mn7 on graphene prefers a two-layer motif and exhibits a ferrimagnetic coupling. The magnetic moment of the Mn7 cluster increases from 5.0 ?B at its free-standing state to about 6.0 ?B upon adsorption on graphene. Mn7 cluster also induces about 0.3 ?B of magnetic moment in the graphene layer, leading to an overall enhancement of 1.3 ?B magnetic moment for Mn7 on graphene. Detail electron transfer and bonding analysis have been carried out to investigate the origin of the magnetic enhancement.

  5. Quantitative Analysis of Clustered DNA Damages Induced by Silicon Beams of Different Kinetic Energy

    SciTech Connect (OSTI)

    Keszenman D. J.; Keszenman, D.J.; Bennett, P.V.; Sutherland, B.M.; Wilson, P.F.

    2013-05-14

    Humans may b exposed to highly energetic charged particle radiation as a result of medical treatments, occupational activitie or accidental events. In recent years, our increasing presence and burgeoning interest in space exploration beyond low Earth orbit has led to a large increase in the research of the biological effects ofcharged particle radiation typical of that encountered in the space radiation environment. The study of the effects of these types of radiation qualities in terms ofDNA damage induction and repair is fundamental to understand mechanisms both underlying their greater biological effectiveness as we)) as the short and long term risks of health effects such as carcinogenesis, degen rative diseases and premature aging. Charged particle radiation induces a variety of DNA alterations, notably bistranded clustered damages, defined as two or more closely-opposed strand break , oxidized bases or abasic sites within a few helical turns. The induction of such highly complex DNA damage enhances the probability of incorrect or incomplete repair and thus constitutes greater potential for genomic instability, cell death and transformation.

  6. The extended Zel'dovich mass functions of clusters and isolated clusters in the presence of primordial non-gaussianity

    SciTech Connect (OSTI)

    Lim, Seunghwan; Lee, Jounghun E-mail: jounghun@astro.snu.ac.kr

    2014-09-10

    We present new formulae for the mass functions of the clusters and the isolated clusters with non-Gaussian initial conditions. For this study, we adopt the extended Zel'dovich (EZL) model as a basic framework, focusing on the case of primordial non-Gaussianity of the local type whose degree is quantified by a single parameter, f {sub nl}. By making a quantitative comparison with the N-body results, we first demonstrate that the EZL formula with the constant values of three fitting parameters still works remarkably well for the local f {sub nl} case. We also modify the EZL formula to find an analytic expression for the mass function of isolated clusters, which turns out to have only one fitting parameter other than the overall normalization factor and showed that the modified EZL formula with a constant value of the fitting parameter matches excellently the N-body results with various values of f {sub nl} at various redshifts. Given the simplicity of the generalized EZL formulae and their good agreements with the numerical results, we finally conclude that the EZL mass functions of the massive clusters and isolated clusters should be useful as an analytic guideline to constrain the scale dependence of the primordial non-Gaussianity of the local type.

  7. WIYN open cluster study. LIX. Radial velocity membership of the evolved population of the old open cluster NGC 6791

    SciTech Connect (OSTI)

    Tofflemire, Benjamin M.; Gosnell, Natalie M.; Mathieu, Robert D.; Platais, Imants E-mail: imants@pha.jhu.edu

    2014-10-01

    The open cluster NGC 6791 has been the focus of much recent study due to its intriguing combination of old age and high metallicity (?8 Gyr, [Fe/H] = +0.30), as well as its location within the Kepler field. As part of the WIYN Open Cluster Study, we present precise (? = 0.38 km s{sup 1}) radial velocities for proper motion candidate members of NGC 6791 from Platais et al. Our survey, extending down to g' ? 16.8, is comprised of the evolved cluster population, including blue stragglers, giants, and horizontal branch stars. Of the 280 proper-motion-selected stars above our magnitude limit, 93% have at least one radial velocity measurement and 79% have three measurements over the course of at least 200 days, sufficient for secure radial-velocity-determined membership of non-velocity-variable stars. The Platais et al. proper motion catalog includes 12 anomalous horizontal branch candidates blueward of the red clump, of which we find only 4 to be cluster members. Three fall slightly blueward of the red clump and the fourth is consistent with being a blue straggler. The cleaned color-magnitude diagram shows a richly populated red giant branch and a blue straggler population. Half of the blue stragglers are in binaries. From our radial velocity measurement distribution, we find the cluster's radial velocity dispersion to be ? {sub c} = 0.62 0.10 km s{sup 1}. This corresponds to a dynamical mass of ?4600 M {sub ?}.

  8. A GRAND DESIGN FOR GALAXY CLUSTERS: CONNECTIONS AND PREDICTIONS

    SciTech Connect (OSTI)

    Cavaliere, A.; Lapi, A.; Fusco-Femiano, R.

    2011-11-20

    We analyze with our entropy-based Supermodel a library of 12 galaxy clusters featuring extended X-ray observations of their intracluster plasma (ICP). The few intrinsic parameters of the model-basically, the central level and the outer slope of the entropy profile-enable us to uniformly derive not only robust snapshots of the ICP thermal state, but also the 'concentration' parameter marking the age of the host dark matter (DM) halo. We test these profiles for consistency with numerical simulations and observations. We find the central and the outer entropy correlate, so that these clusters split into two main classes defined on the basis of low (LE) or high entropy (HE) conditions prevailing throughout the ICP. We also find inverse correlations between the central/outer entropy and the halo concentration. We interpret these in terms of mapping the ICP progress on timescales around 5 Gyr toward higher concentrations, under the drive of the DM halo development. The progress proceeds from HE clusters to LE clusters, toward states of deeper entropy erosion by radiative cooling in the inner regions and of decreasing outer entropy production as the accretion peters out. We propose these radial and time features constitute a cluster Grand Design that we use here to derive a number of predictions. For HE clusters we predict sustained outer temperature profiles. For LEs we expect the outer entropy ramp to bend over; hence the temperature declines before steepening at low z; this feature goes together with an increasing turbulent support, a condition that can be directly probed with the Sunyaev-Zel'dovich effect. We finally discuss the looming out of two intermediate subsets: a wiggled HE-tilde at low z that features central temperature profiles retaining imprints of entropy discharged by active galactic nuclei or deep mergers and high-z LEs where the cosmogony/cosmology had little time to enforce a sharp outer entropy bending.

  9. Quantum Monte Carlo methods and lithium cluster properties

    SciTech Connect (OSTI)

    Owen, R.K.

    1990-12-01

    Properties of small lithium clusters with sizes ranging from n = 1 to 5 atoms were investigated using quantum Monte Carlo (QMC) methods. Cluster geometries were found from complete active space self consistent field (CASSCF) calculations. A detailed development of the QMC method leading to the variational QMC (V-QMC) and diffusion QMC (D-QMC) methods is shown. The many-body aspect of electron correlation is introduced into the QMC importance sampling electron-electron correlation functions by using density dependent parameters, and are shown to increase the amount of correlation energy obtained in V-QMC calculations. A detailed analysis of D-QMC time-step bias is made and is found to be at least linear with respect to the time-step. The D-QMC calculations determined the lithium cluster ionization potentials to be 0.1982(14) [0.1981], 0.1895(9) [0.1874(4)], 0.1530(34) [0.1599(73)], 0.1664(37) [0.1724(110)], 0.1613(43) [0.1675(110)] Hartrees for lithium clusters n = 1 through 5, respectively; in good agreement with experimental results shown in the brackets. Also, the binding energies per atom was computed to be 0.0177(8) [0.0203(12)], 0.0188(10) [0.0220(21)], 0.0247(8) [0.0310(12)], 0.0253(8) [0.0351(8)] Hartrees for lithium clusters n = 2 through 5, respectively. The lithium cluster one-electron density is shown to have charge concentrations corresponding to nonnuclear attractors. The overall shape of the electronic charge density also bears a remarkable similarity with the anisotropic harmonic oscillator model shape for the given number of valence electrons.

  10. Genomic analyses of bacterial porin-cytochrome gene clusters

    SciTech Connect (OSTI)

    Shi, Liang; Fredrickson, James K.; Zachara, John M.

    2014-11-26

    In this study, the porin-cytochrome (Pcc) protein complex is responsible for trans-outer membrane electron transfer during extracellular reduction of Fe(III) by the dissimilatory metal-reducing bacterium Geobacter sulfurreducens PCA. The identified and characterized Pcc complex of G. sulfurreducens PCA consists of a porin-like outer-membrane protein, a periplasmic 8-heme c type cytochrome (c-Cyt) and an outer-membrane 12-heme c-Cyt, and the genes encoding the Pcc proteins are clustered in the same regions of genome (i.e., the pcc gene clusters) of G. sulfurreducens PCA. A survey of additionally microbial genomes has identified the pcc gene clusters in all sequenced Geobacter spp. and other bacteria from six different phyla, including Anaeromyxobacter dehalogenans 2CP-1, A. dehalogenans 2CP-C, Anaeromyxobacter sp. K, Candidatus Kuenenia stuttgartiensis, Denitrovibrio acetiphilus DSM 12809, Desulfurispirillum indicum S5, Desulfurivibrio alkaliphilus AHT2, Desulfurobacterium thermolithotrophum DSM 11699, Desulfuromonas acetoxidans DSM 684, Ignavibacterium album JCM 16511, and Thermovibrio ammonificans HB-1. The numbers of genes in the pcc gene clusters vary, ranging from two to nine. Similar to the metal-reducing (Mtr) gene clusters of other Fe(III)-reducing bacteria, such as Shewanella spp., additional genes that encode putative c-Cyts with predicted cellular localizations at the cytoplasmic membrane, periplasm and outer membrane often associate with the pcc gene clusters. This suggests that the Pcc-associated c-Cyts may be part of the pathways for extracellular electron transfer reactions. The presence of pcc gene clusters in the microorganisms that do not reduce solid-phase Fe(III) and Mn(IV) oxides, such as D. alkaliphilus AHT2 and I. album JCM 16511, also suggests that some of the pcc gene clusters may be involved in extracellular

  11. Interatomic scattering in energy dependent photoelectron spectra of Ar clusters

    SciTech Connect (OSTI)

    Patanen, M.; Benkoula, S.; Nicolas, C.; Goel, A.; Antonsson, E.; Neville, J. J.; Miron, C.

    2015-09-28

    Soft X-ray photoelectron spectra of Ar 2p levels of atomic argon and argon clusters are recorded over an extended range of photon energies. The Ar 2p intensity ratios between atomic argon and clusters’ surface and bulk components reveal oscillations similar to photoelectron extended X-ray absorption fine structure signal (PEXAFS). We demonstrate here that this technique allows us to analyze separately the PEXAFS signals from surface and bulk sites of free-standing, neutral clusters, revealing a bond contraction at the surface.

  12. OpenCL now Available on Dirac GPU Cluster

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

    OpenCL now Available on Dirac GPU Cluster OpenCL now Available on Dirac GPU Cluster October 30, 2013 by Francesca Verdier As requested by many Dirac users, NERSC is migrating Dirac to a newer Linux version to enable capabilities such as OpenCL. We aim to convert the whole Dirac system to Scientific Linux 6.3 by Mid-November. We have migrated the beta nodes to Scientific Linux 6.3. Please run some test jobs to make sure your code will work in the new system. In particular, please test your

  13. Dirac GPU Cluster to be Retired December 12

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

    Dirac GPU Cluster to be Retired December 12 Dirac GPU Cluster to be Retired December 12 November 12, 2014 by Francesca Verdier As previously announced, the Dirac GPU testbed will be retired at 17:00 PST on Friday, December 12, 2014. It has served its intended purpose of allowing NESRC staff and users to evaluate GPU technologies. Subscribe via RSS Subscribe Browse by Date August 2016 June 2016 May 2016 April 2016 January 2016 December 2015 November 2015 October 2015 September 2015 August 2015

  14. Aqueous sulfate separation by crystallization of sulfatewater clusters

    SciTech Connect (OSTI)

    Custelcean, Radu; Williams, Neil J.; Seipp, Charles A.

    2015-08-07

    An effective approach to separating sulfates from aqueous solutions is based on the crystallization of extended [SO4(H2O) 52-]n sulfatewater clusters with a bis(guanidinium) ligand. The ligand was generated in situ by hydrazone condensation in water, thus avoiding elaborate syntheses, tedious purifications, and organic solvents. Crystallization of sulfatewater clusters represents an alternative to the now established sulfate separation strategies that involve encapsulating the naked anion.

  15. Method for discovering relationships in data by dynamic quantum clustering

    DOE Patents [OSTI]

    Weinstein, Marvin; Horn, David

    2014-10-28

    Data clustering is provided according to a dynamical framework based on quantum mechanical time evolution of states corresponding to data points. To expedite computations, we can approximate the time-dependent Hamiltonian formalism by a truncated calculation within a set of Gaussian wave-functions (coherent states) centered around the original points. This allows for analytic evaluation of the time evolution of all such states, opening up the possibility of exploration of relationships among data-points through observation of varying dynamical-distances among points and convergence of points into clusters. This formalism may be further supplemented by preprocessing, such as dimensional reduction through singular value decomposition and/or feature filtering.

  16. Los Humeros Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    (0) 10 References Area Overview Geothermal Area Profile Location: Chignautla, Puebla, Mexico Exploration Region: Transmexican Volcanic Belt GEA Development Phase:...

  17. Deep Washington photometry of inconspicuous star cluster candidates in the Large Magellanic Cloud

    SciTech Connect (OSTI)

    Choudhury, Samyaday; Subramaniam, Annapurni; Piatti, Andrés E.

    2015-02-01

    We present deep Washington photometry of 45 poorly populated star cluster candidates in the Large Magellanic Cloud (LMC). We have performed a systematic study to estimate the parameters of the cluster candidates by matching theoretical isochrones to the cleaned and dereddened cluster color–magnitude diagrams. We were able to estimate the basic parameters for 33 clusters, out of which 23 are identified as single clusters and 10 are found to be members of double clusters. The other 12 cluster candidates have been classified as possible clusters/asterisms. About 50% of the true clusters are in the 100–300 Myr age range, whereas some are older or younger. We have discussed the distribution of age, location, and reddening with respect to field, as well as the size of true clusters. The sizes and masses of the studied sample are found to be similar to that of open clusters in the Milky Way. Our study adds to the lower end of cluster mass distribution in the LMC, suggesting that the LMC, apart from hosting rich clusters, also has formed small, less massive open clusters in the 100–300 Myr age range.

  18. H-Area Seepage Basins

    SciTech Connect (OSTI)

    Stejskal, G.

    1990-12-01

    During the third quarter of 1990 the wells which make up the H-Area Seepage Basins (H-HWMF) monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, nonvolatile beta, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, nonvolatile beta, trichloroethylene (TCE), tetrachloroethylene, lead, cadmium, arsenic, and total radium.

  19. AreaMapWeb copy

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

    ORNL ETTP CITY OF OAK RIDGE MAP AREA (below) 170 170 62 162 162 62 62 61 61 62 61 95 95 61 61 58 95 62 129 321 411 411 321 321 129 11W 11E 11 70 11 11 70 11 11 70 70 40 40 140 140 40 75 40 40 40 640 640 75 75 75 75 61 62 ALCOA MARYVILLE LENOIR CITY FARRAGUT LOUDON OLIVER SPRINGS OAK RIDGE KNOXVILLE AIRPORT McGhee Tyson Municipal Airport (Knoxville Airport) Route between Knoxville Airport, Downtown Knoxville, and Oak Ridge area Take left lane for I-40 West to Nashville, Chattanooga No. 376A Oak

  20. THE HST/ACS COMA CLUSTER SURVEY. II. DATA DESCRIPTION AND SOURCE CATALOGS

    SciTech Connect (OSTI)

    Hammer, Derek; Verdoes Kleijn, Gijs; Den Brok, Mark; Peletier, Reynier F.; Hoyos, Carlos; Balcells, Marc; Aguerri, Alfonso L.; Ferguson, Henry C.; Goudfrooij, Paul; Carter, David; Guzman, Rafael; Smith, Russell J.; Lucey, John R.; Graham, Alister W.; Trentham, Neil; Peng, Eric; Puzia, Thomas H.; Jogee, Shardha; Batcheldor, Dan; Bridges, Terry J.

    2010-11-15

    The Coma cluster, Abell 1656, was the target of an HST-ACS Treasury program designed for deep imaging in the F475W and F814W passbands. Although our survey was interrupted by the ACS instrument failure in early 2007, the partially completed survey still covers {approx}50% of the core high-density region in Coma. Observations were performed for 25 fields that extend over a wide range of cluster-centric radii ({approx}1.75 Mpc or 1{sup 0}) with a total coverage area of 274 arcmin{sup 2}. The majority of the fields are located near the core region of Coma (19/25 pointings) with six additional fields in the southwest region of the cluster. In this paper, we present reprocessed images and SEXTRACTOR source catalogs for our survey fields, including a detailed description of the methodology used for object detection and photometry, the subtraction of bright galaxies to measure faint underlying objects, and the use of simulations to assess the photometric accuracy and completeness of our catalogs. We also use simulations to perform aperture corrections for the SEXTRACTOR Kron magnitudes based only on the measured source flux and its half-light radius. We have performed photometry for {approx}73,000 unique objects; approximately one-half of our detections are brighter than the 10{sigma} point-source detection limit at F814W = 25.8 mag (AB). The slight majority of objects (60%) are unresolved or only marginally resolved by ACS. We estimate that Coma members are 5%-10% of all source detections, which consist of a large population of unresolved compact sources (primarily globular clusters but also ultra-compact dwarf galaxies) and a wide variety of extended galaxies from a cD galaxy to dwarf low surface brightness galaxies. The red sequence of Coma member galaxies has a color-magnitude relation with a constant slope and dispersion over 9 mag (-21 < M {sub F814W} < -13). The initial data release for the HST-ACS Coma Treasury program was made available to the public in 2008

  1. Probability and consequences of a rapid boron dilution sequence in a PWR

    SciTech Connect (OSTI)

    Diamond, D.J.; Kohut, P.; Nourbakhsh, H.; Valtonen, K.; Secker, P.

    1995-11-01

    The reactor restart scenario is one of several beyond-design-basis events in a pressurized water reactor (PWR) which can lead to rapid boron dilution in the core. This in turn can lead to a power excursion and the potential for fuel damage. A probabilistic analysis had been done for this event for a European PWR. The estimated core damage frequency was found to be high partially because of a high frequency for a LOOP and assumptions regarding operator actions. As a result, a program of analysis and experiment was initiated and corrective actions were taken. A system was installed so that the suction of the charging pumps would switch to the highly borated refueling water storage tank (RWST) when there was a trip of the RCPs. This was felt to reduce the estimated core damage frequency to an acceptable level. In the US, this original study prompted the Nuclear Regulatory Commission to issue an information notice to follow work being done in this area and to initiate studies such as the work at BNL reported herein. In order to see if the core damage frequency might be as high in US plants, a probabilistic assessment of this scenario was done for three plants. Two important conservative assumptions in this analysis were that (1) the mixing of the injectant was insignificant and (2) fuel damage occurs when the slug passes through the core. In order to study the first assumption, analysis was carried out for two of the plants using a mixing model. The second assumption was studied by calculating the neutronic response of the core to a slug of deborated water for one of the plants. All three types of analyses are summarized below. More information is available in the original report.

  2. 200 area TEDF sample schedule

    SciTech Connect (OSTI)

    Brown, M.J.

    1995-03-22

    This document summarizes the sampling criteria associated with the 200 Area Treatment Effluent Facility (TEDF) that are needed to comply with the requirements of the Washington State Discharge Permit No. WA ST 4502 and good engineering practices at the generator streams that feed into TEDF. In addition, this document Identifies the responsible parties for both sampling and data transference.

  3. A NEW H? EMISSION-LINE SURVEY IN THE ORION NEBULA CLUSTER

    SciTech Connect (OSTI)

    Szegedi-Elek, E.; Kun, M.; Pl, A.; Balzs, L. G.; Reipurth, B.; Willman, M.

    2013-10-01

    We present results from an H? emission line survey in a 1 deg{sup 2} area centered on the Orion Nebula Cluster, obtained with the Wide Field Grism Spectrograph 2 on the 2.2 m telescope of the University of Hawaii. We identified 587 stars with H? emission, 99 of which, located mainly in the outer regions of the observed area, have not appeared in previous H? surveys. We determined the equivalent width (EW) of the line and, based on this, classified 372 stars as classical T Tauri stars (CTTSs) and 187 as weak-line T Tauri stars (WTTSs). Simultaneous r', i' photometry indicates a limiting magnitude of r' ? 20 mag, but the sample is incomplete at r' > 17 mag. The surface distribution of the H? emission stars reveals a clustered population and a dispersed population, the former consisting of younger and more massive young stars than the latter. Comparison of the derived EWs with those found in the literature indicates variability of the H? line. We found that the typical amplitudes of the variability are not greater than a factor of two to three in most cases. We identified a subgroup of low-EW stars with infrared signatures indicative of optically thick accretion disks. We studied the correlations between the EW and other properties of the stars. Based on literature data, we examined several properties of our CTTS and WTTS subsamples and found significant differences in mid-infrared color indices, average rotational periods, and spectral energy distribution characteristics of the subsamples.

  4. CLUSTER STATES IN C-12 AND C-14

    SciTech Connect (OSTI)

    Freer, M.; Ashwood, N. I.; Curtis, N.; Malcolm, J.; Munoz-Britton, T.; Wheldon, C.; Ziman, A.; Carter, J.; Fujita, H.; Usman, I.; Buthelezi, Z.; Fortsch, S. V.; Neveling, R.; Perez, S. M.; Smit, F. D.; Fearick, R. W.; Papka, P.; Swartz, J. A.; Brown, S.; Catford, W.; Wilson, G.; Bardayan, Daniel W; Pain, Steven D; Chipps, K.; Grzywacz-Jones, K.; Soic, N.; Adekola, Aderemi S; Achouri, N. L.

    2010-01-01

    The cluster structure of 12C is explored and recent measurements of proton inelastic scattering, suggesting a 2+ state close to 9.6 MeV are presented. Resonant scattering studies of 10Be + 4He used to populate resonances in 14C are briefly discussed.

  5. CLUSTER STATES IN C-12 AND C-14

    SciTech Connect (OSTI)

    Freer, M.; Ashwood, N. I.; Curtis, N.; Malcolm, J.; Munoz-Britton, T.; Wheldon, C.; Ziman, A.; Carter, J.; Fujita, H.; Usman, I.; Buthelezi, Z.; Fortsch, S. V.; Neveling, R.; Perez, S. M.; Smit, F. D.; Fearick, R. W.; Papka, P.; Swartz, J. A.; Brown, S.; Catford, W.; Wilson, G.; Bardayan, Daniel W; Pain, Steven D; Chipps, K.; Grzywacz-Jones, K.; Soic, N.; Achouri, N. L.

    2010-07-01

    The cluster structure of 12C is explored and recent measurements of proton inelastic scattering, suggesting a 2+ state close to 9.6 MeV are presented. Resonant scattering studies of 10Be + 4He used to populate resonances in 14C are briefly discussed.

  6. Message Passing for Linux Clusters with Gigabit Ethernet Mesh Connections

    SciTech Connect (OSTI)

    Jie Chen; Chip Watson; Robert Edwards; Weizhen Mao

    2005-04-01

    Multiple copper-based commodity Gigabit Ethernet (GigE) interconnects (adapters) on a single host can lead to Linux clusters with mesh/torus connections without using expensive switches and high speed network interconnects (NICs). However traditional message passing systems based on TCP for GigE will not perform well for this type of clusters because of the overhead of TCP for multiple GigE links. In this paper, we present two os-bypass message passing systems that are based on a modified M-VIA (an implementation of VIA specification) for two production GigE mesh clusters: one is constructed as a 4 x 8 x 8 (256 nodes) torus and has been in production use for a year; the other is constructed as a 6 x 8 x 8 (384 nodes) torus and was deployed recently. One of the message passing systems targets to a specific application domain and is called QMP and the other is an implementation of MPI specification 1.1. The GigE mesh clusters using these two message passing systems achieve about 18.5 {micro}s half-way round trip latency and 400MB/s total bandwidth, which compare reasonably well to systems using specialized high speed adapters in a switched architecture at much lower costs.

  7. Undecametallic and hexadecametallic ferric oxo–hydroxo/ethoxo pivalate clusters

    SciTech Connect (OSTI)

    Baca, Svetlana G.; Speldrich, Manfred; van Leusen, Jan; Ellern, Arkady; Kögerler, Paul

    2015-03-27

    The synthesis strategies for highly condensed {Fe11} and {Fe16} pivalate clusters have been developed based on archetypal geometrically frustrated triangular {Fe33-O)} motifs that are interlinked via oxo, hydroxo, ethoxo, and carboxylate groups.

  8. Stability and migration of small copper clusters in amorphous dielectrics

    SciTech Connect (OSTI)

    Guzman, David M.; Onofrio, Nicolas; Strachan, Alejandro

    2015-05-21

    We use density functional theory (DFT) to study the thermodynamic stability and migration of copper ions and small clusters embedded in amorphous silicon dioxide. We perform the calculations over an ensemble of statistically independent structures to quantify the role of the intrinsic atomic-level variability in the amorphous matrix affect the properties. The predicted formation energy of a Cu ion in the silica matrix is 2.7 ± 2.4 eV, significantly lower the value for crystalline SiO{sub 2}. Interestingly, we find that Cu clusters of any size are energetically favorable as compared to isolated ions; showing that the formation of metallic clusters does not require overcoming a nucleation barrier as is often assumed. We also find a broad distribution of activation energies for Cu migration, from 0.4 to 1.1 eV. This study provides insights into the stability of nanoscale metallic clusters in silica of interest in electrochemical metallization cell memories and optoelectronics.

  9. Ionization Thresholds of Small Carbon Clusters: Tunable VUVExperiments and Theory

    SciTech Connect (OSTI)

    Belau, Leonid; Wheeler, Steven E.; Ticknor, Brian W.; Ahmed,Musahid; Leone, Stephen R.; Allen, Wesley D.; Schaefer III, Henry F.; Duncan, Michael A.

    2007-07-31

    Small carbon clusters (Cn, n = 2-15) are produced in amolecular beam by pulsed laser vaporization and studied with vacuumultraviolet (VUV) photoionization mass spectrometry. The required VUVradiation in the 8-12 eV range is provided by the Advanced Light Source(ALS) at the Lawrence Berkeley National Laboratory. Mass spectra atvarious ionization energies reveal the qualitative relative abundances ofthe neutral carbon clusters produced. By far the most abundant species isC3. Using the tunability of the ALS, ionization threshold spectra arerecorded for the clusters up to 15 atoms in size. The ionizationthresholds are compared to those measured previously with charge-transferbracketing methods. To interpret the ionization thresholds for differentcluster sizes, new ab initio calculations are carried out on the clustersfor n = 4-10. Geometric structures are optimized at the CCSD(T) levelwith cc-pVTZ (or cc-pVDZ) basis sets, and focal point extrapolations areapplied to both neutral and cation species to determine adiabatic andvertical ionization potentials. The comparison of computed and measuredionization potentials makes it possible to investigate the isomericstructures of the neutral clusters produced in this experiment. Themeasurements are inconclusive for the n = 4-6 species because ofunquenched excited electronic states. However, the data provide evidencefor the prominence of linear structures for the n = 7, 9, 11, 13 speciesand the presence of cyclic C10.

  10. Probability encoding of hydrologic parameters for basalt: Elicitation of expert opinions from a panel of five consulting hydrologists

    SciTech Connect (OSTI)

    Davis, J.D.

    1984-12-10

    The Columbia River Basalts Underlying the Hanford Site in Washington State are being considered as a possible location for a geologic repository for high-level nuclear waste. To investigate the feasibility of a repository at this site, the hydrologic parameters of the site must be evaluated. Among hydrologic parameters of particular interest are the effective porosity of the Cohassett flow top and flow interior and the vertical-to-horizontal hydraulic conductivity, or anisotropy ratio, of the Cohassett flow interior. Site-specific data for these hydrologic parameters are currently inadequate. To obtain credible, auditable, and independently derived estimates of the specified hydrologic parameters for the purpose of preliminary assessment of candidate repository performance, a panel of five nationally recognized hydrologists was assembled. Their expert judgments were quantified during two rounds of Delphi process by means of a probability encoding method developed to estimate the probability distributions of the selected hydrologic variables. 210 refs., 12 figs., 5 tabs.

  11. Entropy flattening, gas clumping, and turbulence in galaxy clusters

    SciTech Connect (OSTI)

    Fusco-Femiano, R.; Lapi, A.

    2014-03-10

    Several physical processes and formation events are expected in cluster outskirts, a vast region up to now essentially not covered by observations. The recent Suzaku (X-ray) and Planck (Sunyaev-Zel'dovich (SZ) effect) observations out to the virial radius have highlighted in these peripheral regions a rather sharp decline of the intracluster gas temperature, an entropy flattening in contrast with the theoretically expected power law increase, the break of the hydrostatic equilibrium even in some relaxed clusters, a derived gas mass fraction above the cosmic value measured from several cosmic microwave background experiments, and a total X-ray mass lower than the weak lensing mass determinations. Here we present the analysis of four clusters (A1795, A2029, A2204, and A133) with the SuperModel that includes a nonthermal pressure component due to turbulence to sustain the hydrostatic equilibrium also in the cluster outskirts. In this way, we obtain a correct determination of the total X-ray mass and of the gas mass fraction; this in turn allows us to determine the level of the gas clumping that can affect the shape of the entropy profiles reported by the Suzaku observations. Our conclusion is that the role of the gas clumping is very marginal and that the observed entropy flattening is due to the rapid decrement of the temperature in the cluster outskirts caused by non-gravitational effects. Moreover, we show that the X-ray/SZ joint analysis from ROSAT and Planck data, as performed in some recent investigations, is inadequate for discriminating between a power law increase and a flattening of the entropy.

  12. Probability encoding of hydrologic parameters for basalt. Elicitation of expert opinions from a panel of five consulting hydrologists

    SciTech Connect (OSTI)

    Runchal, A.K.; Merkhofer, M.W.; Olmsted, E.; Davis, J.D.

    1984-11-01

    The Columbia River basalts underlying the Hanford Site in Washington State are being considered as a possible location for a geologic repository for high-level nuclear waste. To investigate the feasibility of a repository at this site, the hydrologic parameters of the site must be evaluated. Among hydrologic parameters of particular interest are the effective porosity of the Cohassett basalt flow top and flow interior and the vertical-to-horizontal hydraulic conductivity, or anisotropy ratio, of the Cohassett basalt flow interior. The Cohassett basalt flow is the prime candidate horizon for repository studies. Site-specific data for these hydrologic parameters are currently inadequate for the purpose of preliminary assessment of candidate repository performance. To obtain credible, auditable, and independently derived estimates of the specified hydrologic parameters, a panel of five nationally recognized hydrologists was assembled. Their expert judgments were quantified during two rounds of Delphi process by means of a probability encoding method developed to estimate the probability distributions of the selected hydrologic variables. The results indicate significant differences of expert opinion for cumulative probabilities of less than 10% and greater than 90%, but relatively close agreement in the middle ranges of values. The principal causes of the diversity of opinion are believed to be the lack of site-specific data and the absence of a single, widely accepted, conceptual or theoretical basis for analyzing these variables.

  13. Areas Participating in the Reformulated Gasoline Program

    Gasoline and Diesel Fuel Update (EIA)

    Reformulated Gasoline Program Contents * Introduction * Mandated RFG Program Areas o Table 1. Mandated RFG Program Areas * RFG Program Opt-In Areas o Table 2. RFG Program Opt-In Areas * RFG Program Opt-Out Procedures and Areas o Table 3. History of EPA Rulemaking on Opt-Out Procedures o Table 4. RFG Program Opt-Out Areas * State Programs o Table 5. State Reformulated Gasoline Programs * Endnotes Spreadsheets Referenced in this Article * Reformulated Gasoline Control Area Populations Related EIA

  14. The Use of Positive Matrix Factorization with Conditional Probability Functions in Air Quality Studies: An Application to Hydrocarbon Emissions in Houston, Texas

    SciTech Connect (OSTI)

    Xie, YuLong; Berkowitz, Carl M.

    2006-06-01

    As part of a study to identify groups of compounds (source categories) associated with different processing facilities, a multivariate receptor model called Positive Matrix Factorization (PMF) was applied to hourly average concentrations of volatile organic compounds (VOCs) measured at five Photochemical Assessment Monitoring Stations (PAMS) located near the Ship Channel in Houston, Texas. The observations were made between June and October, 2003, and limited to nighttime measurements (21:00 pm 6:00 am) in order to remove the complexity of photochemical processing and associated changes in the concentrations of primary and secondary VOCs. Six to eight volatile organic compounds source categories were identified for the five Ship Channel sites. The dominant source categories were found to be those associated with petrochemical, chemical industries and fuel evaporation. In contrast, source categories associated with on-road vehicles were found to be relatively insignificant. Although evidence of biogenic emissions was found at almost all the sites, this broad category was significant only at the Wallisville site, which was also the site furthest away from the Ship Channels area and closest to the northeast forest of Texas. Natural gas, accumulation and fuel evaporation sources were found to contribute most to the ambient VOCs, followed by the petrochemical emission of highly reactive ethene and propylene. Solvent / paint industry and fuel evaporation and emission from refineries were next in importance while the on-road vehicle exhaust generally contributed less than 10% of the total ambient VOCs. Specific geographic areas associated with each source category were identified through the use of a Conditional Probability Function (CPF) analysis that related elevated concentrations of key VOCs in each category to a network of grids superimposed on the source inventories of the VOCs.

  15. SIZES, HALF-MASS DENSITIES, AND MASS FUNCTIONS OF STAR CLUSTERS IN THE MERGER REMNANT NGC 1316: CLUES TO THE FATE OF SECOND-GENERATION GLOBULAR CLUSTERS

    SciTech Connect (OSTI)

    Goudfrooij, Paul

    2012-05-10

    We study mass functions of globular clusters derived from Hubble Space Telescope/Advanced Camera for Surveys images of the early-type merger remnant galaxy NGC 1316, which hosts a significant population of metal-rich globular clusters of intermediate age ({approx}3 Gyr). For the old, metal-poor ({sup b}lue{sup )} clusters, the peak mass of the mass function M{sub p} increases with internal half-mass density {rho}{sub h} as M{sub p}{proportional_to}{rho}{sub h}{sup 0.44}, whereas it stays approximately constant with galactocentric distance R{sub gal}. The mass functions of these clusters are consistent with a simple scenario in which they formed with a Schechter initial mass function and evolved subsequently by internal two-body relaxation. For the intermediate-age population of metal-rich ({sup r}ed{sup )} clusters, the faint end of the previously reported power-law luminosity function of the clusters with R{sub gal} > 9 kpc is due to many of those clusters having radii larger than the theoretical maximum value imposed by the tidal field of NGC 1316 at their R{sub gal}. This renders disruption by two-body relaxation ineffective. Only a few such diffuse clusters are found in the inner regions of NGC 1316. Completeness tests indicate that this is a physical effect. Using comparisons with star clusters in other galaxies and cluster disruption calculations using published models, we hypothesize that most red clusters in the low-{rho}{sub h} tail of the initial distribution have already been destroyed in the inner regions of NGC 1316 by tidal shocking, and that several remaining low-{rho}{sub h} clusters will evolve dynamically to become similar to 'faint fuzzies' that exist in several lenticular galaxies. Finally, we discuss the nature of diffuse red clusters in early-type galaxies.

  16. 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.

  17. Variable area light reflecting assembly

    DOE Patents [OSTI]

    Howard, Thomas C.

    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.

  18. Final DOE Areas Feasibility Study

    Office of Legacy Management (LM)

    Management, Washington, DC Weiss Associates Environmental Science, Engineering and Management FINAL DOE AREAS FEASIBILITY STUDY for the: LABORATORY FOR ENERGY-RELATED HEALTH RESEARCH UNIVERSITY OF CALIFORNIA, DAVIS Prepared for: SM Stoller Corporation 2597 B ¾ Road Grand Junction, Colorado 81503 Prepared by: Weiss Associates 5801 Christie Avenue, Suite 600 Emeryville, California 94608-1827 March 07, 2008 Rev. 0 J:\DOE_STOLLER\4110\143\FEASIBILITY_STUDY\20080307_FS_TEXT_REV0.DOC WEISS ASSOCIATES

  19. α -cluster structure of O 18 (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    -cluster structure of O 18 Citation Details In-Document Search Title: -cluster structure of O 18 Authors: Avila, M. L. ; Rogachev, G. V. ; Goldberg, V. Z. ; Johnson, E. D. ; ...

  20. Advances in the ab initio description of nuclear three-cluster...

    Office of Scientific and Technical Information (OSTI)

    description of nuclear three-cluster systems Citation Details In-Document Search Title: Advances in the ab initio description of nuclear three-cluster systems Authors: Redondo, C R ...