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Sample records for iii large-scale field

  1. The Effective Field Theory of Cosmological Large Scale Structures...

    Office of Scientific and Technical Information (OSTI)

    The Effective Field Theory of Cosmological Large Scale Structures Citation Details In-Document Search Title: The Effective Field Theory of Cosmological Large Scale Structures...

  2. Relic vector field and CMB large scale anomalies

    SciTech Connect (OSTI)

    Chen, Xingang; Wang, Yi E-mail: yw366@cam.ac.uk

    2014-10-01

    We study the most general effects of relic vector fields on the inflationary background and density perturbations. Such effects are observable if the number of inflationary e-folds is close to the minimum requirement to solve the horizon problem. We show that this can potentially explain two CMB large scale anomalies: the quadrupole-octopole alignment and the quadrupole power suppression. We discuss its effect on the parity anomaly. We also provide analytical template for more detailed data comparison.

  3. The effective field theory of cosmological large scale structures

    SciTech Connect (OSTI)

    Carrasco, John Joseph M.; Hertzberg, Mark P.; Senatore, Leonardo

    2012-09-20

    Large scale structure surveys will likely become the next leading cosmological probe. In our universe, matter perturbations are large on short distances and small at long scales, i.e. strongly coupled in the UV and weakly coupled in the IR. To make precise analytical predictions on large scales, we develop an effective field theory formulated in terms of an IR effective fluid characterized by several parameters, such as speed of sound and viscosity. These parameters, determined by the UV physics described by the Boltzmann equation, are measured from N-body simulations. We find that the speed of sound of the effective fluid is c2s ? 106c2 and that the viscosity contributions are of the same order. The fluid describes all the relevant physics at long scales k and permits a manifestly convergent perturbative expansion in the size of the matter perturbations ?(k) for all the observables. As an example, we calculate the correction to the power spectrum at order ?(k)4. As a result, the predictions of the effective field theory are found to be in much better agreement with observation than standard cosmological perturbation theory, already reaching percent precision at this order up to a relatively short scale k ? 0.24h Mpc1.

  4. Scalable parallel distance field construction for large-scale applications

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

    Yu, Hongfeng; Xie, Jinrong; Ma, Kwan -Liu; Kolla, Hemanth; Chen, Jacqueline H.

    2015-10-01

    Computing distance fields is fundamental to many scientific and engineering applications. Distance fields can be used to direct analysis and reduce data. In this paper, we present a highly scalable method for computing 3D distance fields on massively parallel distributed-memory machines. Anew distributed spatial data structure, named parallel distance tree, is introduced to manage the level sets of data and facilitate surface tracking overtime, resulting in significantly reduced computation and communication costs for calculating the distance to the surface of interest from any spatial locations. Our method supports several data types and distance metrics from real-world applications. We demonstrate itsmore » efficiency and scalability on state-of-the-art supercomputers using both large-scale volume datasets and surface models. We also demonstrate in-situ distance field computation on dynamic turbulent flame surfaces for a petascale combustion simulation. In conclusion, our work greatly extends the usability of distance fields for demanding applications.« less

  5. The IR-resummed Effective Field Theory of Large Scale Structures...

    Office of Scientific and Technical Information (OSTI)

    IR-resummed Effective Field Theory of Large Scale Structures Citation Details In-Document Search Title: The IR-resummed Effective Field Theory of Large Scale Structures We present a ...

  6. Single-field consistency relations of large scale structure

    SciTech Connect (OSTI)

    Creminelli, Paolo; Norea, Jorge; Simonovi?, Marko; Vernizzi, Filippo E-mail: jorge.norena@icc.ub.edu E-mail: filippo.vernizzi@cea.fr

    2013-12-01

    We derive consistency relations for the late universe (CDM and ?CDM): relations between an n-point function of the density contrast ? and an (n+1)-point function in the limit in which one of the (n+1) momenta becomes much smaller than the others. These are based on the observation that a long mode, in single-field models of inflation, reduces to a diffeomorphism since its freezing during inflation all the way until the late universe, even when the long mode is inside the horizon (but out of the sound horizon). These results are derived in Newtonian gauge, at first and second order in the small momentum q of the long mode and they are valid non-perturbatively in the short-scale ?. In the non-relativistic limit our results match with [1]. These relations are a consequence of diffeomorphism invariance; they are not satisfied in the presence of extra degrees of freedom during inflation or violation of the Equivalence Principle (extra forces) in the late universe.

  7. Microsoft Word - NRAP-TRS-III-002-2012_Modeling the Performance of Large Scale CO2 Storage_20121024.docx

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

    Modeling the Performance of Large- Scale CO 2 Storage Systems: A Comparison of Different Sensitivity Analysis Methods 24 October 2012 Office of Fossil Energy NRAP-TRS-III-002-2012 Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy,

  8. PARTICLE ACCELERATION BY COLLISIONLESS SHOCKS CONTAINING LARGE-SCALE MAGNETIC-FIELD VARIATIONS

    SciTech Connect (OSTI)

    Guo, F.; Jokipii, J. R.; Kota, J. E-mail: jokipii@lpl.arizona.ed

    2010-12-10

    Diffusive shock acceleration at collisionless shocks is thought to be the source of many of the energetic particles observed in space. Large-scale spatial variations of the magnetic field have been shown to be important in understanding observations. The effects are complex, so here we consider a simple, illustrative model. Here we solve numerically the Parker transport equation for a shock in the presence of large-scale sinusoidal magnetic-field variations. We demonstrate that the familiar planar-shock results can be significantly altered as a consequence of large-scale, meandering magnetic lines of force. Because the perpendicular diffusion coefficient {kappa}{sub perpendicular} is generally much smaller than the parallel diffusion coefficient {kappa}{sub ||}, the energetic charged particles are trapped and preferentially accelerated along the shock front in the regions where the connection points of magnetic field lines intersecting the shock surface converge, and thus create the 'hot spots' of the accelerated particles. For the regions where the connection points separate from each other, the acceleration to high energies will be suppressed. Further, the particles diffuse away from the 'hot spot' regions and modify the spectra of downstream particle distribution. These features are qualitatively similar to the recent Voyager observations in the Heliosheath. These results are potentially important for particle acceleration at shocks propagating in turbulent magnetized plasmas as well as those which contain large-scale nonplanar structures. Examples include anomalous cosmic rays accelerated by the solar wind termination shock, energetic particles observed in propagating heliospheric shocks, galactic cosmic rays accelerated by supernova blast waves, etc.

  9. LyMAS: Predicting large-scale Ly? forest statistics from the dark matter density field

    SciTech Connect (OSTI)

    Peirani, Sbastien; Colombi, Stphane; Dubois, Yohan; Pichon, Christophe; Weinberg, David H.; Blaizot, Jrmy

    2014-03-20

    We describe Ly? Mass Association Scheme (LyMAS), a method of predicting clustering statistics in the Ly? forest on large scales from moderate-resolution simulations of the dark matter (DM) distribution, with calibration from high-resolution hydrodynamic simulations of smaller volumes. We use the 'Horizon-MareNostrum' simulation, a 50 h {sup 1} Mpc comoving volume evolved with the adaptive mesh hydrodynamic code RAMSES, to compute the conditional probability distribution P(F{sub s} |? {sub s}) of the transmitted flux F{sub s} , smoothed (one-dimensionally, 1D) over the spectral resolution scale, on the DM density contrast ? {sub s}, smoothed (three-dimensionally, 3D) over a similar scale. In this study we adopt the spectral resolution of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) at z = 2.5, and we find optimal results for a DM smoothing length ? = 0.3 h {sup 1} Mpc (comoving). In its simplest form, LyMAS draws randomly from the hydro-calibrated P(F{sub s} |? {sub s}) to convert DM skewers into Ly? forest pseudo-spectra, which are then used to compute cross-sightline flux statistics. In extended form, LyMAS exactly reproduces both the 1D power spectrum and one-point flux distribution of the hydro simulation spectra. Applied to the MareNostrum DM field, LyMAS accurately predicts the two-point conditional flux distribution and flux correlation function of the full hydro simulation for transverse sightline separations as small as 1 h {sup 1} Mpc, including redshift-space distortion effects. It is substantially more accurate than a deterministic density-flux mapping ({sup F}luctuating Gunn-Peterson Approximation{sup )}, often used for large-volume simulations of the forest. With the MareNostrum calibration, we apply LyMAS to 1024{sup 3} N-body simulations of a 300 h {sup 1} Mpc and 1.0 h {sup 1} Gpc cube to produce large, publicly available catalogs of mock BOSS spectra that probe a large comoving volume. LyMAS will be a powerful tool for

  10. Large-Scale Field Study of Landfill Covers at Sandia National Laboratories

    SciTech Connect (OSTI)

    Dwyer, S.F.

    1998-09-01

    A large-scale field demonstration comparing final landfill cover designs has been constructed and is currently being monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle `D' Soil Cover and a RCRA Subtitle `C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for dry environments. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. This paper presents an overview of the ongoing demonstration.

  11. On the possible origin of the large scale cosmic magnetic field

    SciTech Connect (OSTI)

    Coroniti, F. V.

    2014-01-10

    The possibility that the large scale cosmic magnetic field is directly generated at microgauss, equipartition levels during the reionization epoch by collisionless shocks that are forced to satisfy a downstream shear flow boundary condition is investigated through the development of two modelsthe accretion of an ionized plasma onto a weakly ionized cool galactic disk and onto a cool filament of the cosmic web. The dynamical structure and the physical parameters of the models are synthesized from recent cosmological simulations of the early reionization era after the formation of the first stars. The collisionless shock stands upstream of the disk and filament, and its dissipation is determined by ion inertial length Weibel turbulence. The downstream shear boundary condition is determined by the rotational neutral gas flow in the disk and the inward accretion flow along the filament. The shocked plasma is accelerated to the downstream shear flow velocity by the Weibel turbulence, and the relative shearing motion between the electrons and ions produces a strong, ion inertial scale current sheet that generates an equipartition strength, large scale downstream magnetic field, ?10{sup 6} G for the disk and ?6 10{sup 8} G for the filament. By assumption, hydrodynamic turbulence transports the shear-shock generated magnetic flux throughout the disk and filament volume.

  12. Calculation of large scale relative permeabilities from stochastic properties of the permeability field and fluid properties

    SciTech Connect (OSTI)

    Lenormand, R.; Thiele, M.R.

    1997-08-01

    The paper describes the method and presents preliminary results for the calculation of homogenized relative permeabilities using stochastic properties of the permeability field. In heterogeneous media, the spreading of an injected fluid is mainly sue to the permeability heterogeneity and viscosity fingering. At large scale, when the heterogeneous medium is replaced by a homogeneous one, we need to introduce a homogenized (or pseudo) relative permeability to obtain the same spreading. Generally, is derived by using fine-grid numerical simulations (Kyte and Berry). However, this operation is time consuming and cannot be performed for all the meshes of the reservoir. We propose an alternate method which uses the information given by the stochastic properties of the field without any numerical simulation. The method is based on recent developments on homogenized transport equations (the {open_quotes}MHD{close_quotes} equation, Lenormand SPE 30797). The MHD equation accounts for the three basic mechanisms of spreading of the injected fluid: (1) Dispersive spreading due to small scale randomness, characterized by a macrodispersion coefficient D. (2) Convective spreading due to large scale heterogeneities (layers) characterized by a heterogeneity factor H. (3) Viscous fingering characterized by an apparent viscosity ration M. In the paper, we first derive the parameters D and H as functions of variance and correlation length of the permeability field. The results are shown to be in good agreement with fine-grid simulations. The are then derived a function of D, H and M. The main result is that this approach lead to a time dependent . Finally, the calculated are compared to the values derived by history matching using fine-grid numerical simulations.

  13. Primordial Magnetic Field Effects on the CMB and Large-Scale Structure

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

    Yamazaki, Dai G.; Ichiki, Kiyotomo; Kajino, Toshitaka; Mathews, Grant J.

    2010-01-01

    Mmore » agnetic fields are everywhere in nature, and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the turbulent high-temperature environment of the big bang. Such a primordial magnetic field (PMF) would be expected to manifest itself in the cosmic microwave background (CMB) temperature and polarization anisotropies, and also in the formation of large-scale structure. In this paper, we summarize the theoretical framework which we have developed to calculate the PMF power spectrum to high precision. Using this formulation, we summarize calculations of the effects of a PMF which take accurate quantitative account of the time evolution of the cutoff scale. We review the constructed numerical program, which is without approximation, and an improvement over the approach used in a number of previous works for studying the effect of the PMF on the cosmological perturbations. We demonstrate how the PMF is an important cosmological physical process on small scales. We also summarize the current constraints on the PMF amplitude B λ and the power spectral index n B which have been deduced from the available CMB observational data by using our computational framework.« less

  14. Anisotropic diffusion across an external magnetic field and large-scale fluctuations in magnetized plasmas

    SciTech Connect (OSTI)

    Holod, I.; Weiland, J.; Zagorodny, A.

    2005-04-01

    The problem of random motion of charged particles in an external magnetic field is studied under the assumption that the Langevin sources produce anisotropic diffusion in velocity space and the friction force is dependent on the direction of particle motion. It is shown that in the case under consideration, the kinetic equation describing particle transitions in phase space is reduced to the equation with a Fokker-Planck collision term in the general form (nonisotropic friction coefficient and nonzero off-diagonal elements of the diffusion tensor in the velocity space). The solution of such an equation has been obtained and the explicit form of the transition probability is found. Using the obtained transition probability, the mean-square particle displacements in configuration and velocity space were calculated and compared with the results of numerical simulations, showing good agreement. The obtained results are used to generalize the theory of large-scale fluctuations in plasmas to the case of anisotropic diffusion across an external magnetic field. Such diffusion is expected to be observed in the case of an anisotropic k spectrum of fluctuations generating random particle motion (for example, in the case of drift-wave turbulence)

  15. The Lagrangian-space Effective Field Theory of large scale structures

    SciTech Connect (OSTI)

    Porto, Rafael A.; Zaldarriaga, Matias; Senatore, Leonardo E-mail: senatore@stanford.edu

    2014-05-01

    We introduce a Lagrangian-space Effective Field Theory (LEFT) formalism for the study of cosmological large scale structures. Unlike the previous Eulerian-space construction, it is naturally formulated as an effective field theory of extended objects in Lagrangian space. In LEFT the resulting finite size effects are described using a multipole expansion parameterized by a set of time dependent coefficients and organized in powers of the ratio of the wavenumber of interest k over the non-linear scale k{sub NL}. The multipoles encode the effects of the short distance modes on the long-wavelength universe and absorb UV divergences when present. There are no IR divergences in LEFT. Some of the parameters that control the perturbative approach are not assumed to be small and can be automatically resummed. We present an illustrative one-loop calculation for a power law universe. We describe the dynamics both at the level of the equations of motion and through an action formalism.

  16. SDSS-III Baryon Oscillation Spectroscopic Survey data release 12: Galaxy target selection and large-scale structure catalogues

    SciTech Connect (OSTI)

    Reid, Beth; Ho, Shirley; Padmanabhan, Nikhil; Percival, Will J.; Tinker, Jeremy; Tojeiro, Rito; White, Marin; Daniel J. Einstein; Maraston, Claudia; Ross, Ashley J.; Sanchez, Ariel G.; Schlegel, David; Sheldon, Erin; Strauss, Michael A.; Thomas, Daniel; Wake, David; Beutler, Florian; Bizyaev, Dmitry; Bolton, Adam S.; Brownstein, Joel R.; Chuang, Chia -Hsun; Dawson, Kyle; Harding, Paul; Kitaura, Francisco -Shu; Leauthaud, Alexie; Masters, Karen; McBride, Cameron K.; More, Surhud; Olmstead, Matthew D.; Oravetz, Daniel; Nuza, Sebastian E.; Pan, Kaike; Parejko, John; Pforr, Janine; Prada, Francisco; Rodriguez-Torres, Sergio; Salazar-Albornoz, Salvador; Samushia, Lado; Schneider, Donald P.; Scoccola, Claudia G.; Simmons, Audrey; Vargas-Magana, Mariana

    2015-11-17

    The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets for which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large-scale structure catalogues for the final Data Release (DR12) samples and the associated random catalogues that quantify the survey mask. The algorithms are an evolution of those used by the BOSS team to construct catalogues from earlier data, and have been designed to accurately quantify the galaxy sample. Furthermore, the code used, designated mksample, is released with this paper.

  17. SDSS-III Baryon Oscillation Spectroscopic Survey data release 12: Galaxy target selection and large-scale structure catalogues

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

    Reid, Beth; Ho, Shirley; Padmanabhan, Nikhil; Percival, Will J.; Tinker, Jeremy; Tojeiro, Rito; White, Marin; Daniel J. Einstein; Maraston, Claudia; Ross, Ashley J.; et al

    2015-11-17

    The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets formore » which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large-scale structure catalogues for the final Data Release (DR12) samples and the associated random catalogues that quantify the survey mask. The algorithms are an evolution of those used by the BOSS team to construct catalogues from earlier data, and have been designed to accurately quantify the galaxy sample. Furthermore, the code used, designated mksample, is released with this paper.« less

  18. Simplified field-in-field technique for a large-scale implementation in breast radiation treatment

    SciTech Connect (OSTI)

    Fournier-Bidoz, Nathalie; Kirova, Youlia M.; Campana, Francois; Dendale, Remi; Fourquet, Alain

    2012-07-01

    We wanted to evaluate a simplified 'field-in-field' technique (SFF) that was implemented in our department of Radiation Oncology for breast treatment. This study evaluated 15 consecutive patients treated with a simplified field in field technique after breast-conserving surgery for early-stage breast cancer. Radiotherapy consisted of whole-breast irradiation to the total dose of 50 Gy in 25 fractions, and a boost of 16 Gy in 8 fractions to the tumor bed. We compared dosimetric outcomes of SFF to state-of-the-art electronic surface compensation (ESC) with dynamic leaves. An analysis of early skin toxicity of a population of 15 patients was performed. The median volume receiving at least 95% of the prescribed dose was 763 mL (range, 347-1472) for SFF vs. 779 mL (range, 349-1494) for ESC. The median residual 107% isodose was 0.1 mL (range, 0-63) for SFF and 1.9 mL (range, 0-57) for ESC. Monitor units were on average 25% higher in ESC plans compared with SFF. No patient treated with SFF had acute side effects superior to grade 1-NCI scale. SFF created homogenous 3D dose distributions equivalent to electronic surface compensation with dynamic leaves. It allowed the integration of a forward planned concomitant tumor bed boost as an additional multileaf collimator subfield of the tangential fields. Compared with electronic surface compensation with dynamic leaves, shorter treatment times allowed better radiation protection to the patient. Low-grade acute toxicity evaluated weekly during treatment and 2 months after treatment completion justified the pursuit of this technique for all breast patients in our department.

  19. Large scale magnetic fields and coherent structures in nonuniform unmagnetized plasma

    SciTech Connect (OSTI)

    Jucker, Martin; Andrushchenko, Zhanna N.; Pavlenko, Vladimir P.

    2006-07-15

    The properties of streamers and zonal magnetic structures in magnetic electron drift mode turbulence are investigated. The stability of such large scale structures is investigated in the kinetic and the hydrodynamic regime, for which an instability criterion similar to the Lighthill criterion for modulational instability is found. Furthermore, these large scale flows can undergo further nonlinear evolution after initial linear growth, which can lead to the formation of long-lived coherent structures consisting of self-bound wave packets between the surfaces of two different flow velocities with an expected modification of the anomalous electron transport properties.

  20. A large scale coherent magnetic field: interactions with free streaming particles and limits from the CMB

    SciTech Connect (OSTI)

    Adamek, Julian; Durrer, Ruth; Fenu, Elisa; Vonlanthen, Marc E-mail: ruth.durrer@unige.ch E-mail: marc.vonlanthen@unige.ch

    2011-06-01

    We study a homogeneous and nearly-isotropic Universe permeated by a homogeneous magnetic field. Together with an isotropic fluid, the homogeneous magnetic field, which is the primary source of anisotropy, leads to a plane-symmetric Bianchi I model of the Universe. However, when free-streaming relativistic particles are present, they generate an anisotropic pressure which counteracts the one from the magnetic field such that the Universe becomes isotropized. We show that due to this effect, the CMB temperature anisotropy from a homogeneous magnetic field is significantly suppressed if the neutrino masses are smaller than 0.3 eV.

  1. Running Large Scale Jobs

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

    Running Large Scale Jobs Running Large Scale Jobs Users face various challenges with running and scaling large scale jobs on peta-scale production systems. For example, certain applications may not have enough memory per core, the default environment variables may need to be adjusted, or I/O dominates run time. This page lists some available programming and run time tuning options and tips users can try on their large scale applications on Hopper for better performance. Try different compilers

  2. Running Large Scale Jobs

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

    try on their large scale applications on Hopper for better performance. Try different compilers and compiler options The available compilers on Hopper are PGI, Cray, Intel, GNU,...

  3. NONLINEAR FORCE-FREE FIELD EXTRAPOLATION OF A CORONAL MAGNETIC FLUX ROPE SUPPORTING A LARGE-SCALE SOLAR FILAMENT FROM A PHOTOSPHERIC VECTOR MAGNETOGRAM

    SciTech Connect (OSTI)

    Jiang, Chaowei; Wu, S. T.; Hu, Qiang; Feng, Xueshang E-mail: wus@uah.edu E-mail: fengx@spaceweather.ac.cn

    2014-05-10

    Solar filaments are commonly thought to be supported in magnetic dips, in particular, in those of magnetic flux ropes (FRs). In this Letter, based on the observed photospheric vector magnetogram, we implement a nonlinear force-free field (NLFFF) extrapolation of a coronal magnetic FR that supports a large-scale intermediate filament between an active region and a weak polarity region. This result is a first, in the sense that current NLFFF extrapolations including the presence of FRs are limited to relatively small-scale filaments that are close to sunspots and along main polarity inversion lines (PILs) with strong transverse field and magnetic shear, and the existence of an FR is usually predictable. In contrast, the present filament lies along the weak-field region (photospheric field strength ? 100G), where the PIL is very fragmented due to small parasitic polarities on both sides of the PIL and the transverse field has a low signal-to-noise ratio. Thus, extrapolating a large-scale FR in such a case represents a far more difficult challenge. We demonstrate that our CESE-MHD-NLFFF code is sufficient for the challenge. The numerically reproduced magnetic dips of the extrapolated FR match observations of the filament and its barbs very well, which strongly supports the FR-dip model for filaments. The filament is stably sustained because the FR is weakly twisted and strongly confined by the overlying closed arcades.

  4. Effects of the scatter in sunspot group tilt angles on the large-scale magnetic field at the solar surface

    SciTech Connect (OSTI)

    Jiang, J.; Cameron, R. H.; Schüssler, M.

    2014-08-10

    The tilt angles of sunspot groups represent the poloidal field source in Babcock-Leighton-type models of the solar dynamo and are crucial for the build-up and reversals of the polar fields in surface flux transport (SFT) simulations. The evolution of the polar field is a consequence of Hale's polarity rules, together with the tilt angle distribution which has a systematic component (Joy's law) and a random component (tilt-angle scatter). We determine the scatter using the observed tilt angle data and study the effects of this scatter on the evolution of the solar surface field using SFT simulations with flux input based upon the recorded sunspot groups. The tilt angle scatter is described in our simulations by a random component according to the observed distributions for different ranges of sunspot group size (total umbral area). By performing simulations with a number of different realizations of the scatter we study the effect of the tilt angle scatter on the global magnetic field, especially on the evolution of the axial dipole moment. The average axial dipole moment at the end of cycle 17 (a medium-amplitude cycle) from our simulations was 2.73 G. The tilt angle scatter leads to an uncertainty of 0.78 G (standard deviation). We also considered cycle 14 (a weak cycle) and cycle 19 (a strong cycle) and show that the standard deviation of the axial dipole moment is similar for all three cycles. The uncertainty mainly results from the big sunspot groups which emerge near the equator. In the framework of Babcock-Leighton dynamo models, the tilt angle scatter therefore constitutes a significant random factor in the cycle-to-cycle amplitude variability, which strongly limits the predictability of solar activity.

  5. The effect of the geomagnetic field on cosmic ray energy estimates and large scale anisotropy searches on data from the Pierre Auger Observatory

    SciTech Connect (OSTI)

    Abreu, P.; Aglietta, M.; Ahn, E.J.; Albuquerque, I.F.M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; ,

    2011-11-01

    We present a comprehensive study of the influence of the geomagnetic field on the energy estimation of extensive air showers with a zenith angle smaller than 60{sup o}, detected at the Pierre Auger Observatory. The geomagnetic field induces an azimuthal modulation of the estimated energy of cosmic rays up to the {approx} 2% level at large zenith angles. We present a method to account for this modulation of the reconstructed energy. We analyse the effect of the modulation on large scale anisotropy searches in the arrival direction distributions of cosmic rays. At a given energy, the geomagnetic effect is shown to induce a pseudo-dipolar pattern at the percent level in the declination distribution that needs to be accounted for. In this work, we have identified and quantified a systematic uncertainty affecting the energy determination of cosmic rays detected by the surface detector array of the Pierre Auger Observatory. This systematic uncertainty, induced by the influence of the geomagnetic field on the shower development, has a strength which depends on both the zenith and the azimuthal angles. Consequently, we have shown that it induces distortions of the estimated cosmic ray event rate at a given energy at the percent level in both the azimuthal and the declination distributions, the latter of which mimics an almost dipolar pattern. We have also shown that the induced distortions are already at the level of the statistical uncertainties for a number of events N {approx_equal} 32 000 (we note that the full Auger surface detector array collects about 6500 events per year with energies above 3 EeV). Accounting for these effects is thus essential with regard to the correct interpretation of large scale anisotropy measurements taking explicitly profit from the declination distribution.

  6. Large scale tracking algorithms.

    SciTech Connect (OSTI)

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  7. Method and infrastructure for cycle-reproducible simulation on large scale digital circuits on a coordinated set of field-programmable gate arrays (FPGAs)

    DOE Patents [OSTI]

    Asaad, Sameh W; Bellofatto, Ralph E; Brezzo, Bernard; Haymes, Charles L; Kapur, Mohit; Parker, Benjamin D; Roewer, Thomas; Tierno, Jose A

    2014-01-28

    A plurality of target field programmable gate arrays are interconnected in accordance with a connection topology and map portions of a target system. A control module is coupled to the plurality of target field programmable gate arrays. A balanced clock distribution network is configured to distribute a reference clock signal, and a balanced reset distribution network is coupled to the control module and configured to distribute a reset signal to the plurality of target field programmable gate arrays. The control module and the balanced reset distribution network are cooperatively configured to initiate and control a simulation of the target system with the plurality of target field programmable gate arrays. A plurality of local clock control state machines reside in the target field programmable gate arrays. The local clock state machines are configured to generate a set of synchronized free-running and stoppable clocks to maintain cycle-accurate and cycle-reproducible execution of the simulation of the target system. A method is also provided.

  8. Magnetic Fields in Population III Star Formation

    SciTech Connect (OSTI)

    Turk, Matthew J.; Oishi, Jeffrey S.; Abel, Tom; Bryan, Greg

    2012-02-22

    We study the buildup of magnetic fields during the formation of Population III star-forming regions, by conducting cosmological simulations from realistic initial conditions and varying the Jeans resolution. To investigate this in detail, we start simulations from identical initial conditions, mandating 16, 32 and 64 zones per Jeans length, and studied the variation in their magnetic field amplification. We find that, while compression results in some amplification, turbulent velocity fluctuations driven by the collapse can further amplify an initially weak seed field via dynamo action, provided there is sufficient numerical resolution to capture vortical motions (we find this requirement to be 64 zones per Jeans length, slightly larger than, but consistent with previous work run with more idealized collapse scenarios). We explore saturation of amplification of the magnetic field, which could potentially become dynamically important in subsequent, fully-resolved calculations. We have also identified a relatively surprising phenomena that is purely hydrodynamic: the higher-resolved simulations possess substantially different characteristics, including higher infall-velocity, increased temperatures inside 1000 AU, and decreased molecular hydrogen content in the innermost region. Furthermore, we find that disk formation is suppressed in higher-resolution calculations, at least at the times that we can follow the calculation. We discuss the effect this may have on the buildup of disks over the accretion history of the first clump to form as well as the potential for gravitational instabilities to develop and induce fragmentation.

  9. Large-Scale Information Systems

    SciTech Connect (OSTI)

    D. M. Nicol; H. R. Ammerlahn; M. E. Goldsby; M. M. Johnson; D. E. Rhodes; A. S. Yoshimura

    2000-12-01

    Large enterprises are ever more dependent on their Large-Scale Information Systems (LSLS), computer systems that are distinguished architecturally by distributed components--data sources, networks, computing engines, simulations, human-in-the-loop control and remote access stations. These systems provide such capabilities as workflow, data fusion and distributed database access. The Nuclear Weapons Complex (NWC) contains many examples of LSIS components, a fact that motivates this research. However, most LSIS in use grew up from collections of separate subsystems that were not designed to be components of an integrated system. For this reason, they are often difficult to analyze and control. The problem is made more difficult by the size of a typical system, its diversity of information sources, and the institutional complexities associated with its geographic distribution across the enterprise. Moreover, there is no integrated approach for analyzing or managing such systems. Indeed, integrated development of LSIS is an active area of academic research. This work developed such an approach by simulating the various components of the LSIS and allowing the simulated components to interact with real LSIS subsystems. This research demonstrated two benefits. First, applying it to a particular LSIS provided a thorough understanding of the interfaces between the system's components. Second, it demonstrated how more rapid and detailed answers could be obtained to questions significant to the enterprise by interacting with the relevant LSIS subsystems through simulated components designed with those questions in mind. In a final, added phase of the project, investigations were made on extending this research to wireless communication networks in support of telemetry applications.

  10. Large-Scale Renewable Energy Guide Webinar

    Broader source: Energy.gov [DOE]

    Webinar introduces the “Large Scale Renewable Energy Guide." The webinar will provide an overview of this important FEMP guide, which describes FEMP's approach to large-scale renewable energy projects and provides guidance to Federal agencies and the private sector on how to develop a common process for large-scale renewable projects.

  11. Large-Scale Liquid Hydrogen Handling Equipment

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

    8, 2007 Jerry Gillette Large-Scale Liquid Hydrogen Handling Equipment Hydrogen Delivery Analysis Meeting Argonne National Laboratory Some Delivery Pathways Will Necessitate the Use of Large- Scale Liquid Hydrogen Handling Equipment „ Potential Scenarios include: - Production plant shutdowns - Summer-peak storage „ Equipment Needs include: - Storage tanks - Liquid Pumps - Vaporizers - Ancillaries 2 1 Concern is that Scaling up from Small Units Could Significantly Underestimate Costs of Larger

  12. Large-Scale PCA for Climate

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

    Large-Scale PCA for Climate Large-Scale PCA for Climate The most widely used tool for extracting important patterns from the measurements of atmospheric and oceanic variables is the Empirical Orthogonal Function (EOF) technique. EOFs are popular because of their simplicity and their ability to reduce the dimensionality of large nonlinear, high-dimensional systems into fewer dimensions while preserving the most important patterns of variations in the measurements. Because EOFs are a particular

  13. The Theory of Quantized Fields. III

    DOE R&D Accomplishments [OSTI]

    Schwinger, J.

    1953-05-01

    In this paper we discuss the electromagnetic field, as perturbed by a prescribed current. All quantities of physical interest in various situations, eigenvalues, eigenfunctions, and transformation probabilities, are derived from a general transformation function which is expressed in a non-Hermitian representation. The problems treated are: the determination of the energy-momentum eigenvalues and eigenfunctions for the isolated electromagnetic field, and the energy eigenvalues and eigenfunctions for the field perturbed by a time-independent current that departs from zero only within a finite time interval, and for a time-dependent current that assumes non-vanishing time-independent values initially and finally. The results are applied in a discussion of the intra-red catastrophe and of the adiabatic theorem. It is shown how the latter can be exploited to give a uniform formulation for all problems requiring the evaluation of transition probabilities or eigenvalue displacements.

  14. The Phoenix series large scale LNG pool fire experiments.

    SciTech Connect (OSTI)

    Simpson, Richard B.; Jensen, Richard Pearson; Demosthenous, Byron; Luketa, Anay Josephine; Ricks, Allen Joseph; Hightower, Marion Michael; Blanchat, Thomas K.; Helmick, Paul H.; Tieszen, Sheldon Robert; Deola, Regina Anne; Mercier, Jeffrey Alan; Suo-Anttila, Jill Marie; Miller, Timothy J.

    2010-12-01

    The increasing demand for natural gas could increase the number and frequency of Liquefied Natural Gas (LNG) tanker deliveries to ports across the United States. Because of the increasing number of shipments and the number of possible new facilities, concerns about the potential safety of the public and property from an accidental, and even more importantly intentional spills, have increased. While improvements have been made over the past decade in assessing hazards from LNG spills, the existing experimental data is much smaller in size and scale than many postulated large accidental and intentional spills. Since the physics and hazards from a fire change with fire size, there are concerns about the adequacy of current hazard prediction techniques for large LNG spills and fires. To address these concerns, Congress funded the Department of Energy (DOE) in 2008 to conduct a series of laboratory and large-scale LNG pool fire experiments at Sandia National Laboratories (Sandia) in Albuquerque, New Mexico. This report presents the test data and results of both sets of fire experiments. A series of five reduced-scale (gas burner) tests (yielding 27 sets of data) were conducted in 2007 and 2008 at Sandia's Thermal Test Complex (TTC) to assess flame height to fire diameter ratios as a function of nondimensional heat release rates for extrapolation to large-scale LNG fires. The large-scale LNG pool fire experiments were conducted in a 120 m diameter pond specially designed and constructed in Sandia's Area III large-scale test complex. Two fire tests of LNG spills of 21 and 81 m in diameter were conducted in 2009 to improve the understanding of flame height, smoke production, and burn rate and therefore the physics and hazards of large LNG spills and fires.

  15. Large-Scale Computational Fluid Dynamics

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

    Large-Scale Computational Fluid Dynamics - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management

  16. Large-Scale Renewable Energy Guide | Department of Energy

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

    Large-Scale Renewable Energy Guide Large-Scale Renewable Energy Guide Presentation covers the Large-scale RE Guide: Developing Renewable Energy Projects Larger than 10 MWs at...

  17. Large Scale Computing and Storage Requirements for Advanced Scientific...

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

    Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research: Target 2014 ASCRFrontcover.png Large Scale Computing and Storage Requirements for ...

  18. Determination of Large-Scale Cloud Ice Water Concentration by...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Determination of Large-Scale Cloud Ice Water Concentration by Combining ... Title: Determination of Large-Scale Cloud Ice Water Concentration by Combining Surface ...

  19. Large-Scale Renewable Energy Guide: Developing Renewable Energy...

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

    Large-Scale Renewable Energy Guide: Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities Large-Scale Renewable Energy Guide: Developing Renewable Energy ...

  20. Large Scale Production Computing and Storage Requirements for...

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

    Large Scale Production Computing and Storage Requirements for Fusion Energy Sciences: Target 2017 The NERSC Program Requirements Review "Large Scale Production Computing and ...

  1. Large-Scale Residential Energy Efficiency Programs Based on CFLs...

    Open Energy Info (EERE)

    Large-Scale Residential Energy Efficiency Programs Based on CFLs Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Large-Scale Residential Energy Efficiency Programs Based...

  2. Large-Scale Manufacturing of Nanoparticle-Based Lubrication Additives...

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

    Large-Scale Manufacturing of Nanoparticle-Based Lubrication Additives Large-Scale Manufacturing of Nanoparticle-Based Lubrication Additives PDF icon nanoparticulate-basedlubricati...

  3. Creating Large Scale Database Servers (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Creating Large Scale Database Servers Citation Details In-Document Search Title: Creating Large Scale Database Servers The BaBar experiment at the Stanford Linear Accelerator ...

  4. Rapid Software Prototyping Into Large Scale Control Systems ...

    Office of Scientific and Technical Information (OSTI)

    Rapid Software Prototyping Into Large Scale Control Systems Citation Details In-Document Search Title: Rapid Software Prototyping Into Large Scale Control Systems Authors: Fishler, ...

  5. DLFM library tools for large scale dynamic applications

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

    applications DLFM library tools for large scale dynamic applications Large scale Python and other dynamic applications may spend huge time at startup. The DLFM library,...

  6. ACCOLADES: A Scalable Workflow Framework for Large-Scale Simulation...

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

    ACCOLADES: A Scalable Workflow Framework for Large-Scale Simulation and Analyses of Automotive Engines Title ACCOLADES: A Scalable Workflow Framework for Large-Scale Simulation and...

  7. Electron drift in a large scale solid xenon

    SciTech Connect (OSTI)

    Yoo, J.; Jaskierny, W. F.

    2015-08-21

    A study of charge drift in a large scale optically transparent solid xenon is reported. A pulsed high power xenon light source is used to liberate electrons from a photocathode. The drift speeds of the electrons are measured using a 8.7 cm long electrode in both the liquid and solid phase of xenon. In the liquid phase (163 K), the drift speed is 0.193 ± 0.003 cm/μs while the drift speed in the solid phase (157 K) is 0.397 ± 0.006 cm/μs at 900 V/cm over 8.0 cm of uniform electric fields. Furthermore, it is demonstrated that a factor two faster electron drift speed in solid phase xenon compared to that in liquid in a large scale solid xenon.

  8. Electron drift in a large scale solid xenon

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

    Yoo, J.; Jaskierny, W. F.

    2015-08-21

    A study of charge drift in a large scale optically transparent solid xenon is reported. A pulsed high power xenon light source is used to liberate electrons from a photocathode. The drift speeds of the electrons are measured using a 8.7 cm long electrode in both the liquid and solid phase of xenon. In the liquid phase (163 K), the drift speed is 0.193 ± 0.003 cm/μs while the drift speed in the solid phase (157 K) is 0.397 ± 0.006 cm/μs at 900 V/cm over 8.0 cm of uniform electric fields. Furthermore, it is demonstrated that a factor twomore » faster electron drift speed in solid phase xenon compared to that in liquid in a large scale solid xenon.« less

  9. Large-Scale PV Integration Study

    SciTech Connect (OSTI)

    Lu, Shuai; Etingov, Pavel V.; Diao, Ruisheng; Ma, Jian; Samaan, Nader A.; Makarov, Yuri V.; Guo, Xinxin; Hafen, Ryan P.; Jin, Chunlian; Kirkham, Harold; Shlatz, Eugene; Frantzis, Lisa; McClive, Timothy; Karlson, Gregory; Acharya, Dhruv; Ellis, Abraham; Stein, Joshua; Hansen, Clifford; Chadliev, Vladimir; Smart, Michael; Salgo, Richard; Sorensen, Rahn; Allen, Barbara; Idelchik, Boris

    2011-07-29

    This research effort evaluates the impact of large-scale photovoltaic (PV) and distributed generation (DG) output on NV Energy’s electric grid system in southern Nevada. It analyzes the ability of NV Energy’s generation to accommodate increasing amounts of utility-scale PV and DG, and the resulting cost of integrating variable renewable resources. The study was jointly funded by the United States Department of Energy and NV Energy, and conducted by a project team comprised of industry experts and research scientists from Navigant Consulting Inc., Sandia National Laboratories, Pacific Northwest National Laboratory and NV Energy.

  10. (Sparsity in large scale scientific computation)

    SciTech Connect (OSTI)

    Ng, E.G.

    1990-08-20

    The traveler attended a conference organized by the 1990 IBM Europe Institute at Oberlech, Austria. The theme of the conference was on sparsity in large scale scientific computation. The conference featured many presentations and other activities of direct interest to ORNL research programs on sparse matrix computations and parallel computing, which are funded by the Applied Mathematical Sciences Subprogram of the DOE Office of Energy Research. The traveler presented a talk on his work at ORNL on the development of efficient algorithms for solving sparse nonsymmetric systems of linear equations. The traveler held numerous technical discussions on issues having direct relevance to the research programs on sparse matrix computations and parallel computing at ORNL.

  11. Batteries for Large Scale Energy Storage

    SciTech Connect (OSTI)

    Soloveichik, Grigorii L.

    2011-07-15

    In recent years, with the deployment of renewable energy sources, advances in electrified transportation, and development in smart grids, the markets for large-scale stationary energy storage have grown rapidly. Electrochemical energy storage methods are strong candidate solutions due to their high energy density, flexibility, and scalability. This review provides an overview of mature and emerging technologies for secondary and redox flow batteries. New developments in the chemistry of secondary and flow batteries as well as regenerative fuel cells are also considered. Advantages and disadvantages of current and prospective electrochemical energy storage options are discussed. The most promising technologies in the short term are high-temperature sodium batteries with β”-alumina electrolyte, lithium-ion batteries, and flow batteries. Regenerative fuel cells and lithium metal batteries with high energy density require further research to become practical.

  12. Supporting large-scale computational science

    SciTech Connect (OSTI)

    Musick, R., LLNL

    1998-02-19

    Business needs have driven the development of commercial database systems since their inception. As a result, there has been a strong focus on supporting many users, minimizing the potential corruption or loss of data, and maximizing performance metrics like transactions per second, or TPC-C and TPC-D results. It turns out that these optimizations have little to do with the needs of the scientific community, and in particular have little impact on improving the management and use of large-scale high-dimensional data. At the same time, there is an unanswered need in the scientific community for many of the benefits offered by a robust DBMS. For example, tying an ad-hoc query language such as SQL together with a visualization toolkit would be a powerful enhancement to current capabilities. Unfortunately, there has been little emphasis or discussion in the VLDB community on this mismatch over the last decade. The goal of the paper is to identify the specific issues that need to be resolved before large-scale scientific applications can make use of DBMS products. This topic is addressed in the context of an evaluation of commercial DBMS technology applied to the exploration of data generated by the Department of Energy`s Accelerated Strategic Computing Initiative (ASCI). The paper describes the data being generated for ASCI as well as current capabilities for interacting with and exploring this data. The attraction of applying standard DBMS technology to this domain is discussed, as well as the technical and business issues that currently make this an infeasible solution.

  13. Large-Scale Algal Cultivation, Harvesting and Downstream Processing Workshop

    Office of Energy Efficiency and Renewable Energy (EERE)

    ATP3 (Algae Testbed Public-Private Partnership) is hosting the Large-Scale Algal Cultivation, Harvesting and Downstream Processing Workshop on November 2–6, 2015, at the Arizona Center for Algae Technology and Innovation in Mesa, Arizona. Topics will include practical applications of growing and managing microalgal cultures at production scale (such as methods for handling cultures, screening strains for desirable characteristics, identifying and mitigating contaminants, scaling up cultures for outdoor growth, harvesting and processing technologies, and the analysis of lipids, proteins, and carbohydrates). Related training will include hands-on laboratory and field opportunities.

  14. Stimulated forward Raman scattering in large scale-length laser...

    Office of Scientific and Technical Information (OSTI)

    in large scale-length laser-produced plasmas Citation Details In-Document Search Title: Stimulated forward Raman scattering in large scale-length laser-produced plasmas You ...

  15. Locations of Smart Grid Demonstration and Large-Scale Energy...

    Office of Environmental Management (EM)

    Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects Map of the United States ...

  16. SimFS: A Large Scale Parallel File System Simulator

    Energy Science and Technology Software Center (OSTI)

    2011-08-30

    The software provides both framework and tools to simulate a large-scale parallel file system such as Lustre.

  17. DLFM library tools for large scale dynamic applications

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

    DLFM library tools for large scale dynamic applications DLFM library tools for large scale dynamic applications Large scale Python and other dynamic applications may spend huge time at startup. The DLFM library, developed by Mike Davis at Cray, Inc., is a set of functions that can be incorporated into a dynamically-linked application to provide improved performance during the loading of dynamic libraries when running the application at large scale on Edison. To access this library, do module

  18. Sensitivity technologies for large scale simulation.

    SciTech Connect (OSTI)

    Collis, Samuel Scott; Bartlett, Roscoe Ainsworth; Smith, Thomas Michael; Heinkenschloss, Matthias; Wilcox, Lucas C.; Hill, Judith C.; Ghattas, Omar; Berggren, Martin Olof; Akcelik, Volkan; Ober, Curtis Curry; van Bloemen Waanders, Bart Gustaaf; Keiter, Eric Richard

    2005-01-01

    Sensitivity analysis is critically important to numerous analysis algorithms, including large scale optimization, uncertainty quantification,reduced order modeling, and error estimation. Our research focused on developing tools, algorithms and standard interfaces to facilitate the implementation of sensitivity type analysis into existing code and equally important, the work was focused on ways to increase the visibility of sensitivity analysis. We attempt to accomplish the first objective through the development of hybrid automatic differentiation tools, standard linear algebra interfaces for numerical algorithms, time domain decomposition algorithms and two level Newton methods. We attempt to accomplish the second goal by presenting the results of several case studies in which direct sensitivities and adjoint methods have been effectively applied, in addition to an investigation of h-p adaptivity using adjoint based a posteriori error estimation. A mathematical overview is provided of direct sensitivities and adjoint methods for both steady state and transient simulations. Two case studies are presented to demonstrate the utility of these methods. A direct sensitivity method is implemented to solve a source inversion problem for steady state internal flows subject to convection diffusion. Real time performance is achieved using novel decomposition into offline and online calculations. Adjoint methods are used to reconstruct initial conditions of a contamination event in an external flow. We demonstrate an adjoint based transient solution. In addition, we investigated time domain decomposition algorithms in an attempt to improve the efficiency of transient simulations. Because derivative calculations are at the root of sensitivity calculations, we have developed hybrid automatic differentiation methods and implemented this approach for shape optimization for gas dynamics using the Euler equations. The hybrid automatic differentiation method was applied to a first

  19. 'Sidecars' Pave the Way for Concurrent Analytics of Large-Scale

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

    Simulations 'Sidecars' Pave the Way for Concurrent Analytics of Large-Scale Simulations 'Sidecars' Pave the Way for Concurrent Analytics of Large-Scale Simulations Halo Finder Enhancement Puts Supercomputer Users in the Driver's Seat November 2, 2015 Contact: Kathy Kincade, +1 510 495 2124, kkincade@lbl.gov Nyxfilamentsandreeberhalos In this Reeber halo finder simulation, the blueish haze is a volume rendering of the density field that Nyx calculates every time step. The light blue and

  20. Large-scale anomalies from primordial dissipation

    SciTech Connect (OSTI)

    D'Amico, Guido; Gobbetti, Roberto; Kleban, Matthew; Schillo, Marjorie E-mail: rg1509@nyu.edu E-mail: mls604@nyu.edu

    2013-11-01

    We analyze an inflationary model in which part of the power in density perturbations arises due to particle production. The amount of particle production is modulated by an auxiliary field. Given an initial gradient for the auxiliary field, this model produces a hemispherical power asymmetry and a suppression of power at low multipoles similar to those observed by WMAP and Planck in the CMB temperature. It also predicts an additive contribution to ?T with support only at very small l that is aligned with the direction of the power asymmetry and has a definite sign, as well as small oscillations in the power spectrum at all l.

  1. Energy Department Applauds Nation's First Large-Scale Industrial Carbon

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

    Capture and Storage Facility | Department of Energy Nation's First Large-Scale Industrial Carbon Capture and Storage Facility Energy Department Applauds Nation's First Large-Scale Industrial Carbon Capture and Storage Facility August 24, 2011 - 6:23pm Addthis Washington, D.C. - The U.S. Department of Energy issued the following statement in support of today's groundbreaking for construction of the nation's first large-scale industrial carbon capture and storage (ICCS) facility in Decatur,

  2. Large-Scale Federal Renewable Energy Projects | Department of Energy

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

    Large-Scale Federal Renewable Energy Projects Large-Scale Federal Renewable Energy Projects Renewable energy projects larger than 10 megawatts (MW), also known as utility-scale projects, are complex and typically require private-sector financing. The Federal Energy Management Program (FEMP) developed a guide to help federal agencies, and the developers and financiers that work with them, to successfully install these projects at federal facilities. FEMP's Large-Scale Renewable Energy Guide,

  3. Large-Scale Industrial Carbon Capture, Storage Plant Begins Construction |

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

    Department of Energy Large-Scale Industrial Carbon Capture, Storage Plant Begins Construction Large-Scale Industrial Carbon Capture, Storage Plant Begins Construction August 24, 2011 - 1:00pm Addthis Washington, DC - Construction activities have begun at an Illinois ethanol plant that will demonstrate carbon capture and storage. The project, sponsored by the U.S. Department of Energy's Office of Fossil Energy, is the first large-scale integrated carbon capture and storage (CCS) demonstration

  4. Large Scale Computing and Storage Requirements for Advanced Scientific

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

    Computing Research: Target 2014 Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research: Target 2014 ASCRFrontcover.png Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research An ASCR / NERSC Review January 5-6, 2011 Final Report Large Scale Computing and Storage Requirements for Advanced Scientific Computing Research, Report of the Joint ASCR / NERSC Workshop conducted January 5-6, 2011 Goals This workshop is being

  5. Large Scale Computing and Storage Requirements for Basic Energy Sciences:

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

    Target 2014 Large Scale Computing and Storage Requirements for Basic Energy Sciences: Target 2014 BESFrontcover.png Final Report Large Scale Computing and Storage Requirements for Basic Energy Sciences, Report of the Joint BES/ ASCR / NERSC Workshop conducted February 9-10, 2010 Workshop Agenda The agenda for this workshop is presented here: including presentation times and speaker information. Read More » Workshop Presentations Large Scale Computing and Storage Requirements for Basic

  6. Large Scale Computing and Storage Requirements for High Energy Physics

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

    Large Scale Computing and Storage Requirements for High Energy Physics HEPFrontcover.png Large Scale Computing and Storage Requirements for High Energy Physics An HEP / ASCR / NERSC Workshop November 12-13, 2009 Report Large Scale Computing and Storage Requirements for High Energy Physics, Report of the Joint HEP / ASCR / NERSC Workshop conducted Nov. 12-13, 2009 https://www.nersc.gov/assets/HPC-Requirements-for-Science/HEPFrontcover.png Goals This workshop was organized by the Department of

  7. Development of an integrated in-situ remediation technology. Topical report for task No. 12 and 13 entitled: Large scale field test of the Lasagna{trademark} process, September 26, 1994--May 25, 1996

    SciTech Connect (OSTI)

    Athmer, C.J.; Ho, Sa V.; Hughes, B.M.

    1997-04-01

    Contamination in low permeability soils poses a significant technical challenge to in-situ remediation efforts. Poor accessibility to the contaminants and difficulty in delivery of treatment reagents have rendered existing in-situ treatments such as bioremediation, vapor extraction, pump and treat rather ineffective when applied to low permeability soils present at many contaminated sites. This technology is an integrated in-situ treatment in which established geotechnical methods are used to instant degradation zones directly in the contaminated soil and electroosmosis is utilized to move the contaminants back and forth through those zones until the treatment is completed. This topical report summarizes the results of the field experiment conducted at the Paducah Gaseous Diffusion Plant in Paducah, KY. The test site covered 15 feet wide by 10 feet across and 15 feet deep with steel panels as electrodes and wickdrains containing granular activated carbon as treatment zone& The electrodes and treatment zones were installed utilizing innovative adaptation of existing emplacement technologies. The unit was operated for four months, flushing TCE by electroosmosis from the soil into the treatment zones where it was trapped by the activated carbon. The scale up from laboratory units to this field scale was very successful with respect to electrical parameters as weft as electroosmotic flow. Soil samples taken throughout the site before and after the test showed over 98% TCE removal, with most samples showing greater than 99% removal.

  8. Overcoming the Barrier to Achieving Large-Scale Production -...

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

    Semprius Confidential 1 Overcoming the Barriers to Achieving Large-Scale Production - A ... August 31, 2011 Semprius Confidential 2 Semprius Overview Background Company: * Leading ...

  9. 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...

  10. A Model for Turbulent Combustion Simulation of Large Scale Hydrogen...

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

    A Model for Turbulent Combustion Simulation of Large Scale Hydrogen Explosions Event Sponsor: Argonne Leadership Computing Facility Seminar Start Date: Oct 6 2015 - 10:00am...

  11. Stimulated forward Raman scattering in large scale-length laser...

    Office of Scientific and Technical Information (OSTI)

    Stimulated forward Raman scattering in large scale-length laser-produced plasmas Citation Details In-Document Search Title: Stimulated forward Raman scattering in large ...

  12. Strategies to Finance Large-Scale Deployment of Renewable Energy...

    Open Energy Info (EERE)

    to Finance Large-Scale Deployment of Renewable Energy Projects: An Economic Development and Infrastructure Approach Jump to: navigation, search Tool Summary LAUNCH TOOL Name:...

  13. Understanding large scale HPC systems through scalable monitoring...

    Office of Scientific and Technical Information (OSTI)

    HPC systems through scalable monitoring and analysis. Citation Details In-Document Search Title: Understanding large scale HPC systems through scalable monitoring and analysis. ...

  14. FEMP Helps Federal Facilities Develop Large-Scale Renewable Energy...

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

    jobs, and advancing national goals for energy security. The guide describes the fundamentals of deploying financially attractive, large-scale renewable energy projects and...

  15. 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...

  16. Energy Department Applauds Nation's First Large-Scale Industrial...

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

    ... News Media Contact: 202-586-4940 Addthis Related Articles Large-Scale Industrial Carbon ... designed National Sequestration Education Center, located at Richland Community ...

  17. Large-Scale Hydropower Basics | Department of Energy

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

    Renewable Energy » Hydropower » Large-Scale Hydropower Basics Large-Scale Hydropower Basics August 14, 2013 - 3:11pm Addthis Large-scale hydropower plants are generally developed to produce electricity for government or electric utility projects. These plants are more than 30 megawatts (MW) in size, and there is more than 80,000 MW of installed generation capacity in the United States today. Most large-scale hydropower projects use a dam and a reservoir to retain water from a river. When the

  18. Harvey Wasserman! Large Scale Computing and Storage Requirements...

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

    Large Scale Computing and Storage Requirements for High Energy Physics Research: Target 2017 ...www.nersc.govsciencerequirementsHEP * Mid---morning a

  19. Large Scale Production Computing and Storage Requirements for...

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

    Large Scale Production Computing and Storage Requirements for High Energy Physics: Target 2017 ... Energy's Office of High Energy Physics (HEP), Office of Advanced Scientific ...

  20. Large-scale quasi-geostrophic magnetohydrodynamics

    SciTech Connect (OSTI)

    Balk, Alexander M.

    2014-12-01

    We consider the ideal magnetohydrodynamics (MHD) of a shallow fluid layer on a rapidly rotating planet or star. The presence of a background toroidal magnetic field is assumed, and the 'shallow water' beta-plane approximation is used. We derive a single equation for the slow large length scale dynamics. The range of validity of this equation fits the MHD of the lighter fluid at the top of Earth's outer core. The form of this equation is similar to the quasi-geostrophic (Q-G) equation (for usual ocean or atmosphere), but the parameters are essentially different. Our equation also implies the inverse cascade; but contrary to the usual Q-G situation, the energy cascades to smaller length scales, while the enstrophy cascades to the larger scales. We find the Kolmogorov-type spectrum for the inverse cascade. The spectrum indicates the energy accumulation in larger scales. In addition to the energy and enstrophy, the obtained equation possesses an extra (adiabatic-type) invariant. Its presence implies energy accumulation in the 30° sector around zonal direction. With some special energy input, the extra invariant can lead to the accumulation of energy in zonal magnetic field; this happens if the input of the extra invariant is small, while the energy input is considerable.

  1. Superconducting materials for large scale applications

    SciTech Connect (OSTI)

    Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

    2004-05-06

    Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

  2. Large scale, urban decontamination; developments, historical examples and lessons learned

    SciTech Connect (OSTI)

    Demmer, R.L.

    2007-07-01

    Recent terrorist threats and actions have lead to a renewed interest in the technical field of large scale, urban environment decontamination. One of the driving forces for this interest is the prospect for the cleanup and removal of radioactive dispersal device (RDD or 'dirty bomb') residues. In response, the United States Government has spent many millions of dollars investigating RDD contamination and novel decontamination methodologies. The efficiency of RDD cleanup response will be improved with these new developments and a better understanding of the 'old reliable' methodologies. While an RDD is primarily an economic and psychological weapon, the need to cleanup and return valuable or culturally significant resources to the public is nonetheless valid. Several private companies, universities and National Laboratories are currently developing novel RDD cleanup technologies. Because of its longstanding association with radioactive facilities, the U. S. Department of Energy National Laboratories are at the forefront in developing and testing new RDD decontamination methods. However, such cleanup technologies are likely to be fairly task specific; while many different contamination mechanisms, substrate and environmental conditions will make actual application more complicated. Some major efforts have also been made to model potential contamination, to evaluate both old and new decontamination techniques and to assess their readiness for use. There are a number of significant lessons that can be gained from a look at previous large scale cleanup projects. Too often we are quick to apply a costly 'package and dispose' method when sound technological cleaning approaches are available. Understanding historical perspectives, advanced planning and constant technology improvement are essential to successful decontamination. (authors)

  3. Superconductivity for Large Scale Wind Turbines

    SciTech Connect (OSTI)

    R. Fair; W. Stautner; M. Douglass; R. Rajput-Ghoshal; M. Moscinski; P. Riley; D. Wagner; J. Kim; S. Hou; F. Lopez; K. Haran; J. Bray; T. Laskaris; J. Rochford; R. Duckworth

    2012-10-12

    A conceptual design has been completed for a 10MW superconducting direct drive wind turbine generator employing low temperature superconductors for the field winding. Key technology building blocks from the GE Wind and GE Healthcare businesses have been transferred across to the design of this concept machine. Wherever possible, conventional technology and production techniques have been used in order to support the case for commercialization of such a machine. Appendices A and B provide further details of the layout of the machine and the complete specification table for the concept design. Phase 1 of the program has allowed us to understand the trade-offs between the various sub-systems of such a generator and its integration with a wind turbine. A Failure Modes and Effects Analysis (FMEA) and a Technology Readiness Level (TRL) analysis have been completed resulting in the identification of high risk components within the design. The design has been analyzed from a commercial and economic point of view and Cost of Energy (COE) calculations have been carried out with the potential to reduce COE by up to 18% when compared with a permanent magnet direct drive 5MW baseline machine, resulting in a potential COE of 0.075 $/kWh. Finally, a top-level commercialization plan has been proposed to enable this technology to be transitioned to full volume production. The main body of this report will present the design processes employed and the main findings and conclusions.

  4. ARM - Field Campaign - AIRS Validation Soundings Phase III

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

    govCampaignsAIRS Validation Soundings Phase III ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : AIRS Validation Soundings Phase III 2004.04.19 - 2004.09.05 Lead Scientist : Jimmy Voyles For data sets, see below. Abstract Radiosonde launches from NSA were timed to coincide with overpasses of the Aqua satellite carrying the AIRS sensor for the purpose of providing in situ validation data for development and

  5. ARM - Field Campaign - AIRS Validation Soundings Phase III

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

    govCampaignsAIRS Validation Soundings Phase III ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : AIRS Validation Soundings Phase III 2004.04.02 - 2004.08.10 Lead Scientist : Jimmy Voyles For data sets, see below. Abstract Radiosonde launches from NSA were timed to coincide with overpasses of the Aqua satellite carrying the AIRS sensor for the purpose of providing in situ validation data for development and

  6. ARM - Field Campaign - AIRS Validation Soundings Phase III

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

    III ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : AIRS Validation Soundings Phase III 2004.04.01 - 2004.09.29 Lead Scientist : Jimmy Voyles For data sets, see below. Abstract Radiosonde launches from NSA were timed to coincide with overpasses of the Aqua satellite carrying the AIRS sensor for the purpose of providing in situ validation data for development and testing of AIRS water vapor retrievals

  7. III

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

    III .. III A HIGH RESOLUTION STUDY OF ISOBARIC ANAL.OGUE STATES IN 41K AND 23 Na by George A lbert Keyworth II Department of Physics Duke University A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Physics in the Graduate School of Arts and Sciences of Duke University 1968 I I I I I I I I I I I I I I I I I I I A HIGH RESOLUTION STUDY OF ISOBARIC ANALOGUE STATES IN 41 K - AND 23 Na ,. by George Albert Keyworth II

  8. Large-Scale First-Principles Molecular Dynamics Simulations on...

    Office of Scientific and Technical Information (OSTI)

    for large-scale parallel platforms such as BlueGeneL. Strong scaling tests for a Materials Science application show an 86% scaling efficiency between 1024 and 32,768 CPUs. ...

  9. Self-consistency tests of large-scale dynamics parameterizations...

    Office of Scientific and Technical Information (OSTI)

    In self-consistency tests based on radiative-convective equilibrium (RCE; i.e., no large-scale convergence), we find that simulations either weakly coupled or strongly coupled to ...

  10. ARM - Evaluation Product - Vertical Air Motion during Large-Scale...

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

    ProductsVertical Air Motion during Large-Scale Stratiform Rain ARM Data Discovery Browse ... Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Vertical Air ...

  11. Towards a Large-Scale Recording System: Demonstration of Polymer...

    Office of Scientific and Technical Information (OSTI)

    of Polymer-Based Penetrating Array for Chronic Neural Recording Citation Details In-Document Search Title: Towards a Large-Scale Recording System: Demonstration of Polymer-Based ...

  12. How Three Retail Buyers Source Large-Scale Solar Electricity

    Broader source: Energy.gov [DOE]

    Large-scale, non-utility solar power purchase agreements (PPAs) are still a rarity despite the growing popularity of PPAs across the country. In this webinar, participants will learn more about how...

  13. Cosmological Simulations for Large-Scale Sky Surveys | Argonne...

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

    The focus of cosmology today is on its two mysterious pillars, dark matter and dark energy. Large-scale sky surveys are the current drivers of precision cosmology and have been ...

  14. Cosmological Simulations for Large-Scale Sky Surveys | Argonne...

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

    The focus of cosmology today revolves around two mysterious pillars, dark matter and dark energy. Large-scale sky surveys are the current drivers of precision cosmology and have ...

  15. COLLOQUIUM: Liquid Metal Batteries for Large-scale Energy Storage...

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

    June 22, 2016, 4:15pm to 5:30pm Colloquia MBG Auditorium, PPPL (284 cap.) COLLOQUIUM: Liquid Metal Batteries for Large-scale Energy Storage Dr. Hojong Kim Pennsylvania State ...

  16. The Cielo Petascale Capability Supercomputer: Providing Large-Scale

    Office of Scientific and Technical Information (OSTI)

    Computing for Stockpile Stewardship (Conference) | SciTech Connect Conference: The Cielo Petascale Capability Supercomputer: Providing Large-Scale Computing for Stockpile Stewardship Citation Details In-Document Search Title: The Cielo Petascale Capability Supercomputer: Providing Large-Scale Computing for Stockpile Stewardship Authors: Vigil, Benny Manuel [1] ; Doerfler, Douglas W. [1] + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2013-03-11 OSTI Identifier:

  17. Revised Environmental Assessment Large-Scale, Open-Air Explosive

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

    Environmental Assessment Large-Scale, Open-Air Explosive Detonation, DIVINE STRAKE, at the Nevada Test Site May 2006 Prepared by Department of Energy National Nuclear Security Administration Nevada Site Office Environmental Assessment May 2006 Large-Scale, Open-Air Explosive Detonation, DIVINE STRAKE, at the Nevada Test Site TABLE OF CONTENTS 1.0 PURPOSE AND NEED FOR ACTION.....................................................1-1 1.1 Introduction and

  18. Breakthrough Large-Scale Industrial Project Begins Carbon Capture and

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

    Utilization | Department of Energy Breakthrough Large-Scale Industrial Project Begins Carbon Capture and Utilization Breakthrough Large-Scale Industrial Project Begins Carbon Capture and Utilization January 25, 2013 - 12:00pm Addthis Washington, DC - A breakthrough carbon capture, utilization, and storage (CCUS) project in Texas has begun capturing carbon dioxide (CO2) and piping it to an oilfield for use in enhanced oil recovery (EOR). Read the project factsheet The project at Air Products

  19. Cosmological Simulations for Large-Scale Sky Surveys | Argonne Leadership

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

    Computing Facility Cosmological Simulations for Large-Scale Sky Surveys PI Name: Salman Habib PI Email: habib@anl.gov Institution: Argonne National Laboratory Allocation Program: INCITE Allocation Hours at ALCF: 100 Million Year: 2014 Research Domain: Physics The next generation of large-scale sky surveys aims to establish a new regime of cosmic discovery through fundamental measurements of the universe's geometry and the growth of structure. The aim of this project is to accurately

  20. COLLOQUIUM: Large Scale Superconducting Magnets for Variety of Applications

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

    | Princeton Plasma Physics Lab October 15, 2014, 4:00pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Large Scale Superconducting Magnets for Variety of Applications Professor Joseph Minervini Massachusetts Institute of Technology Presentation: PDF icon Superconducting_Magnet_Technology_for_Fusion_and_Large_Scale_Applications.pdf Over the past several decades the U. S. magnetic confinement fusion program, working in collaboration with international partners, has developed superconductor and

  1. Large Scale Computing and Storage Requirements for Biological and

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

    Environmental Research: Target 2014 Large Scale Computing and Storage Requirements for Biological and Environmental Research: Target 2014 BERFrontcover.png A BER / ASCR / NERSC Workshop May 7-8, 2009 Final Report Large Scale Computing and Storage Requirements for Biological and Environmental Research, Report of the Joint BER / NERSC Workshop Conducted May 7-8, 2009 Rockville, MD Goals This workshop was jointly organized by the Department of Energy's Office of Biological & Environmental

  2. Large Scale Computing and Storage Requirements for Nuclear Physics: Target

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

    2014 Large Scale Computing and Storage Requirements for Nuclear Physics: Target 2014 NPFrontcover.png May 26-27, 2011 Hyatt Regency Bethesda One Bethesda Metro Center (7400 Wisconsin Ave) Bethesda, Maryland, USA 20814 Final Report Large Scale Computing and Storage Requirements for Nuclear Physics Research, Report of the Joint NP / NERSC Workshop Conducted May 26-27, 2011 Bethesda, MD Sponsored by the U.S. Department of Energy Office of Science, Office of Advanced Scientific Computing

  3. Large Scale Production Computing and Storage Requirements for Fusion Energy

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

    Sciences: Target 2017 Large Scale Production Computing and Storage Requirements for Fusion Energy Sciences: Target 2017 The NERSC Program Requirements Review "Large Scale Production Computing and Storage Requirements for Fusion Energy Sciences" is organized by the Department of Energy's Office of Fusion Energy Sciences (FES), Office of Advanced Scientific Computing Research (ASCR), and the National Energy Research Scientific Computing Center (NERSC). The review's goal is to

  4. Large Scale Production Computing and Storage Requirements for High Energy

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

    Physics: Target 2017 Large Scale Production Computing and Storage Requirements for High Energy Physics: Target 2017 HEPlogo.jpg The NERSC Program Requirements Review "Large Scale Computing and Storage Requirements for High Energy Physics" is organized by the Department of Energy's Office of High Energy Physics (HEP), Office of Advanced Scientific Computing Research (ASCR), and the National Energy Research Scientific Computing Center (NERSC). The review's goal is to characterize

  5. Ferroelectric opening switches for large-scale pulsed power drivers.

    SciTech Connect (OSTI)

    Brennecka, Geoffrey L.; Rudys, Joseph Matthew; Reed, Kim Warren; Pena, Gary Edward; Tuttle, Bruce Andrew; Glover, Steven Frank

    2009-11-01

    Fast electrical energy storage or Voltage-Driven Technology (VDT) has dominated fast, high-voltage pulsed power systems for the past six decades. Fast magnetic energy storage or Current-Driven Technology (CDT) is characterized by 10,000 X higher energy density than VDT and has a great number of other substantial advantages, but it has all but been neglected for all of these decades. The uniform explanation for neglect of CDT technology is invariably that the industry has never been able to make an effective opening switch, which is essential for the use of CDT. Most approaches to opening switches have involved plasma of one sort or another. On a large scale, gaseous plasmas have been used as a conductor to bridge the switch electrodes that provides an opening function when the current wave front propagates through to the output end of the plasma and fully magnetizes the plasma - this is called a Plasma Opening Switch (POS). Opening can be triggered in a POS using a magnetic field to push the plasma out of the A-K gap - this is called a Magnetically Controlled Plasma Opening Switch (MCPOS). On a small scale, depletion of electron plasmas in semiconductor devices is used to affect opening switch behavior, but these devices are relatively low voltage and low current compared to the hundreds of kilo-volts and tens of kilo-amperes of interest to pulsed power. This work is an investigation into an entirely new approach to opening switch technology that utilizes new materials in new ways. The new materials are Ferroelectrics and using them as an opening switch is a stark contrast to their traditional applications in optics and transducer applications. Emphasis is on use of high performance ferroelectrics with the objective of developing an opening switch that would be suitable for large scale pulsed power applications. Over the course of exploring this new ground, we have discovered new behaviors and properties of these materials that were here to fore unknown. Some of

  6. Ground movements associated with large-scale underground coal gasification

    SciTech Connect (OSTI)

    Siriwardane, H.J.; Layne, A.W.

    1989-09-01

    The primary objective of this work was to predict the surface and underground movement associated with large-scale multiwell burn sites in the Illinois Basin and Appalachian Basin by using the subsidence/thermomechanical model UCG/HEAT. This code is based on the finite element method. In particular, it can be used to compute (1) the temperature field around an underground cavity when the temperature variation of the cavity boundary is known, and (2) displacements and stresses associated with body forces (gravitational forces) and a temperature field. It is hypothesized that large Underground Coal Gasification (UCG) cavities generated during the line-drive process will be similar to those generated by longwall mining. If that is the case, then as a UCG process continues, the roof of the cavity becomes unstable and collapses. In the UCG/HEAT computer code, roof collapse is modeled using a simplified failure criterion (Lee 1985). It is anticipated that roof collapse would occur behind the burn front; therefore, forward combustion can be continued. As the gasification front propagates, the length of the cavity would become much larger than its width. Because of this large length-to-width ratio in the cavity, ground response behavior could be analyzed by considering a plane-strain idealization. In a plane-strain idealization of the UCG cavity, a cross-section perpendicular to the axis of propagation could be considered, and a thermomechanical analysis performed using a modified version of the two-dimensional finite element code UCG/HEAT. 15 refs., 9 figs., 3 tabs.

  7. EINSTEIN'S SIGNATURE IN COSMOLOGICAL LARGE-SCALE STRUCTURE

    SciTech Connect (OSTI)

    Bruni, Marco; Hidalgo, Juan Carlos; Wands, David

    2014-10-10

    We show how the nonlinearity of general relativity generates a characteristic nonGaussian signal in cosmological large-scale structure that we calculate at all perturbative orders in a large-scale limit. Newtonian gravity and general relativity provide complementary theoretical frameworks for modeling large-scale structure in ?CDM cosmology; a relativistic approach is essential to determine initial conditions, which can then be used in Newtonian simulations studying the nonlinear evolution of the matter density. Most inflationary models in the very early universe predict an almost Gaussian distribution for the primordial metric perturbation, ?. However, we argue that it is the Ricci curvature of comoving-orthogonal spatial hypersurfaces, R, that drives structure formation at large scales. We show how the nonlinear relation between the spatial curvature, R, and the metric perturbation, ?, translates into a specific nonGaussian contribution to the initial comoving matter density that we calculate for the simple case of an initially Gaussian ?. Our analysis shows the nonlinear signature of Einstein's gravity in large-scale structure.

  8. Large-Scale Sequencing: The Future of Genomic Sciences Colloquium

    SciTech Connect (OSTI)

    Margaret Riley; Merry Buckley

    2009-01-01

    Genetic sequencing and the various molecular techniques it has enabled have revolutionized the field of microbiology. Examining and comparing the genetic sequences borne by microbes - including bacteria, archaea, viruses, and microbial eukaryotes - provides researchers insights into the processes microbes carry out, their pathogenic traits, and new ways to use microorganisms in medicine and manufacturing. Until recently, sequencing entire microbial genomes has been laborious and expensive, and the decision to sequence the genome of an organism was made on a case-by-case basis by individual researchers and funding agencies. Now, thanks to new technologies, the cost and effort of sequencing is within reach for even the smallest facilities, and the ability to sequence the genomes of a significant fraction of microbial life may be possible. The availability of numerous microbial genomes will enable unprecedented insights into microbial evolution, function, and physiology. However, the current ad hoc approach to gathering sequence data has resulted in an unbalanced and highly biased sampling of microbial diversity. A well-coordinated, large-scale effort to target the breadth and depth of microbial diversity would result in the greatest impact. The American Academy of Microbiology convened a colloquium to discuss the scientific benefits of engaging in a large-scale, taxonomically-based sequencing project. A group of individuals with expertise in microbiology, genomics, informatics, ecology, and evolution deliberated on the issues inherent in such an effort and generated a set of specific recommendations for how best to proceed. The vast majority of microbes are presently uncultured and, thus, pose significant challenges to such a taxonomically-based approach to sampling genome diversity. However, we have yet to even scratch the surface of the genomic diversity among cultured microbes. A coordinated sequencing effort of cultured organisms is an appropriate place to begin

  9. Large-Scale Industrial CCS Projects Selected for Continued Testing |

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

    Department of Energy CCS Projects Selected for Continued Testing Large-Scale Industrial CCS Projects Selected for Continued Testing June 10, 2010 - 1:00pm Addthis Washington, DC - Three Recovery Act funded projects have been selected by the U.S. Department of Energy (DOE) to continue testing large-scale carbon capture and storage (CCS) from industrial sources. The projects - located in Texas, Illinois, and Louisiana - were initially selected for funding in October 2009 as part of a $1.4

  10. DOE Completes Large-Scale Carbon Sequestration Project Awards | Department

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

    of Energy Large-Scale Carbon Sequestration Project Awards DOE Completes Large-Scale Carbon Sequestration Project Awards November 17, 2008 - 4:58pm Addthis Regional Partner to Demonstrate Safe and Permanent Storage of 2 Million Tons of CO2 at Wyoming Site WASHINGTON, DC - Completing a series of awards through its Regional Carbon Sequestration Partnership Program, the U.S. Department of Energy (DOE) today awarded $66.9 million to the Big Sky Regional Carbon Sequestration Partnership for the

  11. Lessons from Large-Scale Renewable Energy Integration Studies: Preprint

    SciTech Connect (OSTI)

    Bird, L.; Milligan, M.

    2012-06-01

    In general, large-scale integration studies in Europe and the United States find that high penetrations of renewable generation are technically feasible with operational changes and increased access to transmission. This paper describes other key findings such as the need for fast markets, large balancing areas, system flexibility, and the use of advanced forecasting.

  12. EA-1898: Southwest Regional Partnership on Carbon Sequestration Phase III Gordon Creek Project near Price, Utah in Carbon County

    Broader source: Energy.gov [DOE]

    This EA will evaluate the environmental impacts of a proposal for Phase III field deployment to demonstrate commercial-scale carbon storage technologies.This Phase III large-scale carbon dioxide injection project will combine science and engineering from many disciplines to successfully sequester and monitor carbon storage. [NOTE: This EA has been cancelled].

  13. Cosmological implications of the CMB large-scale structure

    SciTech Connect (OSTI)

    Melia, Fulvio

    2015-01-01

    The Wilkinson Microwave Anisotropy Probe (WMAP) and Planck may have uncovered several anomalies in the full cosmic microwave background (CMB) sky that could indicate possible new physics driving the growth of density fluctuations in the early universe. These include an unusually low power at the largest scales and an apparent alignment of the quadrupole and octopole moments. In a ?CDM model where the CMB is described by a Gaussian Random Field, the quadrupole and octopole moments should be statistically independent. The emergence of these low probability features may simply be due to posterior selections from many such possible effects, whose occurrence would therefore not be as unlikely as one might naively infer. If this is not the case, however, and if these features are not due to effects such as foreground contamination, their combined statistical significance would be equal to the product of their individual significances. In the absence of such extraneous factors, and ignoring the biasing due to posterior selection, the missing large-angle correlations would have a probability as low as ?0.1% and the low-l multipole alignment would be unlikely at the ?4.9% level; under the least favorable conditions, their simultaneous observation in the context of the standard model could then be likely at only the ?0.005% level. In this paper, we explore the possibility that these features are indeed anomalous, and show that the corresponding probability of CMB multipole alignment in the R{sub h}=ct universe would then be ?710%, depending on the number of large-scale SachsWolfe induced fluctuations. Since the low power at the largest spatial scales is reproduced in this cosmology without the need to invoke cosmic variance, the overall likelihood of observing both of these features in the CMB is ?7%, much more likely than in ?CDM, if the anomalies are real. The key physical ingredient responsible for this difference is the existence in the former of a maximum fluctuation

  14. GAIA: A WINDOW TO LARGE-SCALE MOTIONS

    SciTech Connect (OSTI)

    Nusser, Adi; Branchini, Enzo; Davis, Marc E-mail: branchin@fis.uniroma3.it

    2012-08-10

    Using redshifts as a proxy for galaxy distances, estimates of the two-dimensional (2D) transverse peculiar velocities of distant galaxies could be obtained from future measurements of proper motions. We provide the mathematical framework for analyzing 2D transverse motions and show that they offer several advantages over traditional probes of large-scale motions. They are completely independent of any intrinsic relations between galaxy properties; hence, they are essentially free of selection biases. They are free from homogeneous and inhomogeneous Malmquist biases that typically plague distance indicator catalogs. They provide additional information to traditional probes that yield line-of-sight peculiar velocities only. Further, because of their 2D nature, fundamental questions regarding vorticity of large-scale flows can be addressed. Gaia, for example, is expected to provide proper motions of at least bright galaxies with high central surface brightness, making proper motions a likely contender for traditional probes based on current and future distance indicator measurements.

  15. LARGE-SCALE MOTIONS IN THE PERSEUS GALAXY CLUSTER

    SciTech Connect (OSTI)

    Simionescu, A.; Werner, N.; Urban, O.; Allen, S. W.; Fabian, A. C.; Sanders, J. S.; Mantz, A.; Nulsen, P. E. J.; Takei, Y.

    2012-10-01

    By combining large-scale mosaics of ROSAT PSPC, XMM-Newton, and Suzaku X-ray observations, we present evidence for large-scale motions in the intracluster medium of the nearby, X-ray bright Perseus Cluster. These motions are suggested by several alternating and interleaved X-ray bright, low-temperature, low-entropy arcs located along the east-west axis, at radii ranging from {approx}10 kpc to over a Mpc. Thermodynamic features qualitatively similar to these have previously been observed in the centers of cool-core clusters, and were successfully modeled as a consequence of the gas sloshing/swirling motions induced by minor mergers. Our observations indicate that such sloshing/swirling can extend out to larger radii than previously thought, on scales approaching the virial radius.

  16. The workshop on iterative methods for large scale nonlinear problems

    SciTech Connect (OSTI)

    Walker, H.F.; Pernice, M.

    1995-12-01

    The aim of the workshop was to bring together researchers working on large scale applications with numerical specialists of various kinds. Applications that were addressed included reactive flows (combustion and other chemically reacting flows, tokamak modeling), porous media flows, cardiac modeling, chemical vapor deposition, image restoration, macromolecular modeling, and population dynamics. Numerical areas included Newton iterative (truncated Newton) methods, Krylov subspace methods, domain decomposition and other preconditioning methods, large scale optimization and optimal control, and parallel implementations and software. This report offers a brief summary of workshop activities and information about the participants. Interested readers are encouraged to look into an online proceedings available at http://www.usi.utah.edu/logan.proceedings. In this, the material offered here is augmented with hypertext abstracts that include links to locations such as speakers` home pages, PostScript copies of talks and papers, cross-references to related talks, and other information about topics addresses at the workshop.

  17. Large-Scale Optimization for Bayesian Inference in Complex Systems

    SciTech Connect (OSTI)

    Willcox, Karen; Marzouk, Youssef

    2013-11-12

    The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimization) Project focused on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimization and inversion methods. The project was a collaborative effort among MIT, the University of Texas at Austin, Georgia Institute of Technology, and Sandia National Laboratories. The research was directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. The MIT--Sandia component of the SAGUARO Project addressed the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas--Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to-observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as ``reduce then sample'' and ``sample then reduce.'' In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to achieve their

  18. UNIVERSITY OF CALIFORNIA The Future of Large Scale Visual Data

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

    CALIFORNIA The Future of Large Scale Visual Data Analysis Joint Facilities User Forum on Data Intensive Computing Oakland, CA E. Wes Bethel Lawrence Berkeley National Laboratory 16 June 2014 16 June 2014 The World that Was: Computational Architectures * Machine architectures - Single CPU, single core - Vector, then single-core MPPs - "Large" SMP platforms - Relatively well balanced: memory, FLOPS,I/O 16 June 2014 The World that Was: Software Architecture * Data Analysis and

  19. Robust, Multifunctional Joint for Large Scale Power Production Stacks -

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

    Energy Innovation Portal Robust, Multifunctional Joint for Large Scale Power Production Stacks Lawrence Berkeley National Laboratory Contact LBL About This Technology DIAGRAM OF BERKELEY LAB'S MULTIFUNCTIONAL JOINT DIAGRAM OF BERKELEY LAB'S MULTIFUNCTIONAL JOINT Technology Marketing SummaryBerkeley Lab scientists have developed a multifunctional joint for metal supported, tubular SOFCs that divides various joint functions so that materials and methods optimizing each function can be chosen

  20. Large-scale ab initio configuration interaction calculations for light

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

    nuclei | Argonne Leadership Computing Facility Large-scale ab initio configuration interaction calculations for light nuclei Authors: Pieter Maris, H Metin Aktulga, Mark A Caprio, Ümit V Çatalyürek, Esmond G Ng, Dossay Oryspayev, Hugh Potter, Erik Saule, Masha Sosonkina, James P Vary, Chao Yang Zheng Zhou In ab-initio Configuration Interaction calculations, the nuclear wavefunction is expanded in Slater determinants of single-nucleon wavefunctions and the many-body Schrodinger equation

  1. Large Scale Computing and Storage Requirements for Fusion Energy Sciences:

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

    Target 2014 High Energy Physics (HEP) Nuclear Physics (NP) Overview Published Reports Case Study FAQs NERSC HPC Achievement Awards Share Your Research User Submitted Research Citations NERSC Citations Home » Science at NERSC » HPC Requirements Reviews » Requirements Reviews: Target 2014 » Fusion Energy Sciences (FES) Large Scale Computing and Storage Requirements for Fusion Energy Sciences: Target 2014 FESFrontcover.png An FES / ASCR / NERSC Workshop August 3-4, 2010 Final Report Large

  2. Large Scale Production Computing and Storage Requirements for Advanced

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

    Scientific Computing Research: Target 2017 Large Scale Production Computing and Storage Requirements for Advanced Scientific Computing Research: Target 2017 ASCRLogo.png This is an invitation-only review organized by the Department of Energy's Office of Advanced Scientific Computing Research (ASCR) and NERSC. The general goal is to determine production high-performance computing, storage, and services that will be needed for ASCR to achieve its science goals through 2017. A specific focus

  3. Large Scale Production Computing and Storage Requirements for Basic Energy

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

    Sciences: Target 2017 Large Scale Production Computing and Storage Requirements for Basic Energy Sciences: Target 2017 BES-Montage.png This is an invitation-only review organized by the Department of Energy's Office of Basic Energy Sciences (BES), Office of Advanced Scientific Computing Research (ASCR), and the National Energy Research Scientific Computing Center (NERSC). The goal is to determine production high-performance computing, storage, and services that will be needed for BES to

  4. Large Scale Production Computing and Storage Requirements for Biological

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

    and Environmental Research: Target 2017 Large Scale Production Computing and Storage Requirements for Biological and Environmental Research: Target 2017 BERmontage.gif September 11-12, 2012 Hilton Rockville Hotel and Executive Meeting Center 1750 Rockville Pike Rockville, MD, 20852-1699 TEL: 1-301-468-1100 Sponsored by: U.S. Department of Energy Office of Science Office of Advanced Scientific Computing Research (ASCR) Office of Biological and Environmental Research (BER) National Energy

  5. Large Scale Production Computing and Storage Requirements for Nuclear

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

    Physics: Target 2017 Large Scale Production Computing and Storage Requirements for Nuclear Physics: Target 2017 NPicon.png This invitation-only review is organized by the Department of Energy's Offices of Nuclear Physics (NP) and Advanced Scientific Computing Research (ASCR) and by NERSC. The goal is to determine production high-performance computing, storage, and services that will be needed for NP to achieve its science goals through 2017. The review brings together DOE Program Managers,

  6. Computational Fluid Dynamics & Large-Scale Uncertainty Quantification for

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

    Wind Energy Fluid Dynamics & Large-Scale Uncertainty Quantification for Wind Energy - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery

  7. Geospatial Optimization of Siting Large-Scale Solar Projects

    SciTech Connect (OSTI)

    Macknick, J.; Quinby, T.; Caulfield, E.; Gerritsen, M.; Diffendorfer, J.; Haines, S.

    2014-03-01

    Recent policy and economic conditions have encouraged a renewed interest in developing large-scale solar projects in the U.S. Southwest. However, siting large-scale solar projects is complex. In addition to the quality of the solar resource, solar developers must take into consideration many environmental, social, and economic factors when evaluating a potential site. This report describes a proof-of-concept, Web-based Geographical Information Systems (GIS) tool that evaluates multiple user-defined criteria in an optimization algorithm to inform discussions and decisions regarding the locations of utility-scale solar projects. Existing siting recommendations for large-scale solar projects from governmental and non-governmental organizations are not consistent with each other, are often not transparent in methods, and do not take into consideration the differing priorities of stakeholders. The siting assistance GIS tool we have developed improves upon the existing siting guidelines by being user-driven, transparent, interactive, capable of incorporating multiple criteria, and flexible. This work provides the foundation for a dynamic siting assistance tool that can greatly facilitate siting decisions among multiple stakeholders.

  8. Measuring and tuning energy efficiency on large scale high performance computing platforms.

    SciTech Connect (OSTI)

    Laros, James H., III

    2011-08-01

    Recognition of the importance of power in the field of High Performance Computing, whether it be as an obstacle, expense or design consideration, has never been greater and more pervasive. While research has been conducted on many related aspects, there is a stark absence of work focused on large scale High Performance Computing. Part of the reason is the lack of measurement capability currently available on small or large platforms. Typically, research is conducted using coarse methods of measurement such as inserting a power meter between the power source and the platform, or fine grained measurements using custom instrumented boards (with obvious limitations in scale). To collect the measurements necessary to analyze real scientific computing applications at large scale, an in-situ measurement capability must exist on a large scale capability class platform. In response to this challenge, we exploit the unique power measurement capabilities of the Cray XT architecture to gain an understanding of power use and the effects of tuning. We apply these capabilities at the operating system level by deterministically halting cores when idle. At the application level, we gain an understanding of the power requirements of a range of important DOE/NNSA production scientific computing applications running at large scale (thousands of nodes), while simultaneously collecting current and voltage measurements on the hosting nodes. We examine the effects of both CPU and network bandwidth tuning and demonstrate energy savings opportunities of up to 39% with little or no impact on run-time performance. Capturing scale effects in our experimental results was key. Our results provide strong evidence that next generation large-scale platforms should not only approach CPU frequency scaling differently, but could also benefit from the capability to tune other platform components, such as the network, to achieve energy efficient performance.

  9. DOE/NNSA Participates in Large-Scale CTBT On-Site Inspection Exercise in

    National Nuclear Security Administration (NNSA)

    Jordan | National Nuclear Security Administration | (NNSA) Participates in Large-Scale CTBT On-Site Inspection Exercise in Jordan Friday, November 28, 2014 - 9:05am Experts from U.S. Department of Energy National Laboratories, including Sandia National Laboratories, Los Alamos National Laboratory, Lawrence Livermore National Laboratory, and Pacific Northwest National Laboratory, are participating in the Comprehensive Nuclear-Test-Ban Treaty (CTBT) Integrated Field Exercise 2014 (IFE14), a

  10. Robust large-scale parallel nonlinear solvers for simulations.

    SciTech Connect (OSTI)

    Bader, Brett William; Pawlowski, Roger Patrick; Kolda, Tamara Gibson

    2005-11-01

    This report documents research to develop robust and efficient solution techniques for solving large-scale systems of nonlinear equations. The most widely used method for solving systems of nonlinear equations is Newton's method. While much research has been devoted to augmenting Newton-based solvers (usually with globalization techniques), little has been devoted to exploring the application of different models. Our research has been directed at evaluating techniques using different models than Newton's method: a lower order model, Broyden's method, and a higher order model, the tensor method. We have developed large-scale versions of each of these models and have demonstrated their use in important applications at Sandia. Broyden's method replaces the Jacobian with an approximation, allowing codes that cannot evaluate a Jacobian or have an inaccurate Jacobian to converge to a solution. Limited-memory methods, which have been successful in optimization, allow us to extend this approach to large-scale problems. We compare the robustness and efficiency of Newton's method, modified Newton's method, Jacobian-free Newton-Krylov method, and our limited-memory Broyden method. Comparisons are carried out for large-scale applications of fluid flow simulations and electronic circuit simulations. Results show that, in cases where the Jacobian was inaccurate or could not be computed, Broyden's method converged in some cases where Newton's method failed to converge. We identify conditions where Broyden's method can be more efficient than Newton's method. We also present modifications to a large-scale tensor method, originally proposed by Bouaricha, for greater efficiency, better robustness, and wider applicability. Tensor methods are an alternative to Newton-based methods and are based on computing a step based on a local quadratic model rather than a linear model. The advantage of Bouaricha's method is that it can use any existing linear solver, which makes it simple to write

  11. Towards physics responsible for large-scale Lyman-α forest bias parameters

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

    Agnieszka M. Cieplak; Slosar, Anze

    2016-03-08

    Using a series of carefully constructed numerical experiments based on hydrodynamic cosmological SPH simulations, we attempt to build an intuition for the relevant physics behind the large scale density (bδ) and velocity gradient (bη) biases of the Lyman-α forest. Starting with the fluctuating Gunn-Peterson approximation applied to the smoothed total density field in real-space, and progressing through redshift-space with no thermal broadening, redshift-space with thermal broadening and hydrodynamically simulated baryon fields, we investigate how approximations found in the literature fare. We find that Seljak's 2012 analytical formulae for these bias parameters work surprisingly well in the limit of no thermalmore » broadening and linear redshift-space distortions. We also show that his bη formula is exact in the limit of no thermal broadening. Since introduction of thermal broadening significantly affects its value, we speculate that a combination of large-scale measurements of bη and the small scale flux PDF might be a sensitive probe of the thermal state of the IGM. Lastly, we find that large-scale biases derived from the smoothed total matter field are within 10–20% to those based on hydrodynamical quantities, in line with other measurements in the literature.« less

  12. Reducing Data Center Loads for a Large-scale, Low Energy Office...

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

    Data Center Loads for a Large- scale, Low-energy Office Building: NREL's Research Support ... National Renewable Energy Laboratory Reducing Data Center Loads for a Large-Scale, ...

  13. HyLights -- Tools to Prepare the Large-Scale European Demonstration...

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

    HYLIGHTS - TOOLS TO PREPARE THE LARGE-SCALE EUROPEAN DEMONSTRATION PROJECTS ON HYDROGEN ... Assist the European Commission and European industry to plan the large-scale demonstration ...

  14. High Fidelity Simulations of Large-Scale Wireless Networks (Plus-Up)

    SciTech Connect (OSTI)

    Onunkwo, Uzoma

    2015-11-01

    Sandia has built a strong reputation in scalable network simulation and emulation for cyber security studies to protect our nation’s critical information infrastructures. Georgia Tech has preeminent reputation in academia for excellence in scalable discrete event simulations, with strong emphasis on simulating cyber networks. Many of the experts in this field, such as Dr. Richard Fujimoto, Dr. George Riley, and Dr. Chris Carothers, have strong affiliations with Georgia Tech. The collaborative relationship that we intend to immediately pursue is in high fidelity simulations of practical large-scale wireless networks using ns-3 simulator via Dr. George Riley. This project will have mutual benefits in bolstering both institutions’ expertise and reputation in the field of scalable simulation for cyber-security studies. This project promises to address high fidelity simulations of large-scale wireless networks. This proposed collaboration is directly in line with Georgia Tech’s goals for developing and expanding the Communications Systems Center, the Georgia Tech Broadband Institute, and Georgia Tech Information Security Center along with its yearly Emerging Cyber Threats Report. At Sandia, this work benefits the defense systems and assessment area with promise for large-scale assessment of cyber security needs and vulnerabilities of our nation’s critical cyber infrastructures exposed to wireless communications.

  15. Large scale obscuration and related climate effects open literature bibliography

    SciTech Connect (OSTI)

    Russell, N.A.; Geitgey, J.; Behl, Y.K.; Zak, B.D.

    1994-05-01

    Large scale obscuration and related climate effects of nuclear detonations first became a matter of concern in connection with the so-called ``Nuclear Winter Controversy`` in the early 1980`s. Since then, the world has changed. Nevertheless, concern remains about the atmospheric effects of nuclear detonations, but the source of concern has shifted. Now it focuses less on global, and more on regional effects and their resulting impacts on the performance of electro-optical and other defense-related systems. This bibliography reflects the modified interest.

  16. Large-scale anisotropy in stably stratified rotating flows

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

    Marino, R.; Mininni, P. D.; Rosenberg, D. L.; Pouquet, A.

    2014-08-28

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

  17. Detecting differential protein expression in large-scale population proteomics

    SciTech Connect (OSTI)

    Ryu, Soyoung; Qian, Weijun; Camp, David G.; Smith, Richard D.; Tompkins, Ronald G.; Davis, Ronald W.; Xiao, Wenzhong

    2014-06-17

    Mass spectrometry-based high-throughput quantitative proteomics shows great potential in clinical biomarker studies, identifying and quantifying thousands of proteins in biological samples. However, methods are needed to appropriately handle issues/challenges unique to mass spectrometry data in order to detect as many biomarker proteins as possible. One issue is that different mass spectrometry experiments generate quite different total numbers of quantified peptides, which can result in more missing peptide abundances in an experiment with a smaller total number of quantified peptides. Another issue is that the quantification of peptides is sometimes absent, especially for less abundant peptides and such missing values contain the information about the peptide abundance. Here, we propose a Significance Analysis for Large-scale Proteomics Studies (SALPS) that handles missing peptide intensity values caused by the two mechanisms mentioned above. Our model has a robust performance in both simulated data and proteomics data from a large clinical study. Because varying patients’ sample qualities and deviating instrument performances are not avoidable for clinical studies performed over the course of several years, we believe that our approach will be useful to analyze large-scale clinical proteomics data.

  18. Presentation on the Large-Scale Renewable Energy Guide | Department of

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

    Energy Presentation on the Large-Scale Renewable Energy Guide Presentation on the Large-Scale Renewable Energy Guide Presentation covers the Large-Scale RE Guide: Developing Renewable Energy Projects Larger than 10 MWs at Federal Facilities for the FUPWG Spring meeting, held on May 22, 2013, in San Francisco, California. Download FEMP's Large-Scale Renewable Energy Guide - Presented by Brad Gustafson (1.75 MB) More Documents & Publications Large-Scale Federal Renewable Energy Projects

  19. Nuclear-pumped lasers for large-scale applications

    SciTech Connect (OSTI)

    Anderson, R.E.; Leonard, E.M.; Shea, R.F.; Berggren, R.R.

    1989-05-01

    Efficient initiation of large-volume chemical lasers may be achieved by neutron induced reactions which produce charged particles in the final state. When a burst mode nuclear reactor is used as the neutron source, both a sufficiently intense neutron flux and a sufficiently short initiation pulse may be possible. Proof-of-principle experiments are planned to demonstrate lasing in a direct nuclear-pumped large-volume system; to study the effects of various neutron absorbing materials on laser performance; to study the effects of long initiation pulse lengths; to demonstrate the performance of large-scale optics and the beam quality that may be obtained; and to assess the performance of alternative designs of burst systems that increase the neutron output and burst repetition rate. 21 refs., 8 figs., 5 tabs.

  20. Nuclear-pumped lasers for large-scale applications

    SciTech Connect (OSTI)

    Anderson, R.E.; Leonard, E.M.; Shea, R.E.; Berggren, R.R.

    1988-01-01

    Efficient initiation of large-volume chemical lasers may be achieved by neutron induced reactions which produce charged particles in the final state. When a burst mode nuclear reactor is used as the neutron source, both a sufficiently intense neutron flux and a sufficient short initiation pulse may be possible. Proof-of-principle experiments are planned to demonstrate lasing in a direct nuclear-pumped large-volume system: to study the effects of various neutron absorbing materials on laser performance; to study the effects of long initiation pulse lengths; to determine the performance of large-scale optics and the beam quality that may bo obtained; and to assess the performance of alternative designs of burst systems that increase the neutron output and burst repetition rate. 21 refs., 7 figs., 5 tabs.

  1. Large-Scale All-Dielectric Metamaterial Perfect Reflectors

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

    Moitra, Parikshit; Slovick, Brian A.; li, Wei; Kravchencko, Ivan I.; Briggs, Dayrl P.; Krishnamurthy, S.; Valentine, Jason

    2015-05-08

    All-dielectric metamaterials offer a potential low-loss alternative to plasmonic metamaterials at optical frequencies. In this paper, we take advantage of the low absorption loss as well as the simple unit cell geometry to demonstrate large-scale (centimeter-sized) all-dielectric metamaterial perfect reflectors made from silicon cylinder resonators. These perfect reflectors, operating in the telecommunications band, were fabricated using self-assembly based nanosphere lithography. In spite of the disorder originating from the self-assembly process, the average reflectance of the metamaterial perfect reflectors is 99.7% at 1530 nm, surpassing the reflectance of metallic mirrors. Moreover, the spectral separation of the electric and magnetic resonances canmore » be chosen to achieve the required reflection bandwidth while maintaining a high tolerance to disorder. Finally, the scalability of this design could lead to new avenues of manipulating light for low-loss and large-area photonic applications.« less

  2. Planning under uncertainty solving large-scale stochastic linear programs

    SciTech Connect (OSTI)

    Infanger, G. . Dept. of Operations Research Technische Univ., Vienna . Inst. fuer Energiewirtschaft)

    1992-12-01

    For many practical problems, solutions obtained from deterministic models are unsatisfactory because they fail to hedge against certain contingencies that may occur in the future. Stochastic models address this shortcoming, but up to recently seemed to be intractable due to their size. Recent advances both in solution algorithms and in computer technology now allow us to solve important and general classes of practical stochastic problems. We show how large-scale stochastic linear programs can be efficiently solved by combining classical decomposition and Monte Carlo (importance) sampling techniques. We discuss the methodology for solving two-stage stochastic linear programs with recourse, present numerical results of large problems with numerous stochastic parameters, show how to efficiently implement the methodology on a parallel multi-computer and derive the theory for solving a general class of multi-stage problems with dependency of the stochastic parameters within a stage and between different stages.

  3. Performance Health Monitoring of Large-Scale Systems

    SciTech Connect (OSTI)

    Rajamony, Ram

    2014-11-20

    This report details the progress made on the ASCR funded project Performance Health Monitoring for Large Scale Systems. A large-­‐scale application may not achieve its full performance potential due to degraded performance of even a single subsystem. Detecting performance faults, isolating them, and taking remedial action is critical for the scale of systems on the horizon. PHM aims to develop techniques and tools that can be used to identify and mitigate such performance problems. We accomplish this through two main aspects. The PHM framework encompasses diagnostics, system monitoring, fault isolation, and performance evaluation capabilities that indicates when a performance fault has been detected, either due to an anomaly present in the system itself or due to contention for shared resources between concurrently executing jobs. Software components called the PHM Control system then build upon the capabilities provided by the PHM framework to mitigate degradation caused by performance problems.

  4. High Fidelity Simulations of Large-Scale Wireless Networks

    SciTech Connect (OSTI)

    Onunkwo, Uzoma; Benz, Zachary

    2015-11-01

    The worldwide proliferation of wireless connected devices continues to accelerate. There are 10s of billions of wireless links across the planet with an additional explosion of new wireless usage anticipated as the Internet of Things develops. Wireless technologies do not only provide convenience for mobile applications, but are also extremely cost-effective to deploy. Thus, this trend towards wireless connectivity will only continue and Sandia must develop the necessary simulation technology to proactively analyze the associated emerging vulnerabilities. Wireless networks are marked by mobility and proximity-based connectivity. The de facto standard for exploratory studies of wireless networks is discrete event simulations (DES). However, the simulation of large-scale wireless networks is extremely difficult due to prohibitively large turnaround time. A path forward is to expedite simulations with parallel discrete event simulation (PDES) techniques. The mobility and distance-based connectivity associated with wireless simulations, however, typically doom PDES and fail to scale (e.g., OPNET and ns-3 simulators). We propose a PDES-based tool aimed at reducing the communication overhead between processors. The proposed solution will use light-weight processes to dynamically distribute computation workload while mitigating communication overhead associated with synchronizations. This work is vital to the analytics and validation capabilities of simulation and emulation at Sandia. We have years of experience in Sandia’s simulation and emulation projects (e.g., MINIMEGA and FIREWHEEL). Sandia’s current highly-regarded capabilities in large-scale emulations have focused on wired networks, where two assumptions prevent scalable wireless studies: (a) the connections between objects are mostly static and (b) the nodes have fixed locations.

  5. Large-Scale Spray Releases: Additional Aerosol Test Results

    SciTech Connect (OSTI)

    Daniel, Richard C.; Gauglitz, Phillip A.; Burns, Carolyn A.; Fountain, Matthew S.; Shimskey, Rick W.; Billing, Justin M.; Bontha, Jagannadha R.; Kurath, Dean E.; Jenks, Jeromy WJ; MacFarlan, Paul J.; Mahoney, Lenna A.

    2013-08-01

    One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2012b), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used

  6. Comparison of prestellar core elongations and large-scale molecular cloud structures in the Lupus I region

    SciTech Connect (OSTI)

    Poidevin, Frdrick; Ade, Peter A. R.; Hargrave, Peter C.; Nutter, David; Angile, Francesco E.; Devlin, Mark J.; Klein, Jeffrey; Benton, Steven J.; Netterfield, Calvin B.; Chapin, Edward L.; Fissel, Laura M.; Gandilo, Natalie N.; Fukui, Yasuo; Gundersen, Joshua O.; Korotkov, Andrei L.; Matthews, Tristan G.; Novak, Giles; Moncelsi, Lorenzo; Mroczkowski, Tony K.; Olmi, Luca; and others

    2014-08-10

    Turbulence and magnetic fields are expected to be important for regulating molecular cloud formation and evolution. However, their effects on sub-parsec to 100 parsec scales, leading to the formation of starless cores, are not well understood. We investigate the prestellar core structure morphologies obtained from analysis of the Herschel-SPIRE 350 ?m maps of the Lupus I cloud. This distribution is first compared on a statistical basis to the large-scale shape of the main filament. We find the distribution of the elongation position angle of the cores to be consistent with a random distribution, which means no specific orientation of the morphology of the cores is observed with respect to the mean orientation of the large-scale filament in Lupus I, nor relative to a large-scale bent filament model. This distribution is also compared to the mean orientation of the large-scale magnetic fields probed at 350 ?m with the Balloon-borne Large Aperture Telescope for Polarimetry during its 2010 campaign. Here again we do not find any correlation between the core morphology distribution and the average orientation of the magnetic fields on parsec scales. Our main conclusion is that the local filament dynamicsincluding secondary filaments that often run orthogonally to the primary filamentand possibly small-scale variations in the local magnetic field direction, could be the dominant factors for explaining the final orientation of each core.

  7. Large Scale Obscuration and Related Climate Effects Workshop: Proceedings

    SciTech Connect (OSTI)

    Zak, B.D.; Russell, N.A.; Church, H.W.; Einfeld, W.; Yoon, D.; Behl, Y.K.

    1994-05-01

    A Workshop on Large Scale Obsurcation and Related Climate Effects was held 29--31 January, 1992, in Albuquerque, New Mexico. The objectives of the workshop were: to determine through the use of expert judgement the current state of understanding of regional and global obscuration and related climate effects associated with nuclear weapons detonations; to estimate how large the uncertainties are in the parameters associated with these phenomena (given specific scenarios); to evaluate the impact of these uncertainties on obscuration predictions; and to develop an approach for the prioritization of further work on newly-available data sets to reduce the uncertainties. The workshop consisted of formal presentations by the 35 participants, and subsequent topical working sessions on: the source term; aerosol optical properties; atmospheric processes; and electro-optical systems performance and climatic impacts. Summaries of the conclusions reached in the working sessions are presented in the body of the report. Copies of the transparencies shown as part of each formal presentation are contained in the appendices (microfiche).

  8. Large-scale BAO signatures of the smallest galaxies

    SciTech Connect (OSTI)

    Dalal, Neal; Pen, Ue-Li; Seljak, Uros E-mail: pen@cita.utoronto.ca

    2010-11-01

    Recent work has shown that at high redshift, the relative velocity between dark matter and baryonic gas is typically supersonic. This relative velocity suppresses the formation of the earliest baryonic structures like minihalos, and the suppression is modulated on large scales. This effect imprints a characteristic shape in the clustering power spectrum of the earliest structures, with significant power on ∼ 100 Mpc scales featuring highly pronounced baryon acoustic oscillations. The amplitude of these oscillations is orders of magnitude larger at z ∼ 20 than previously expected. This characteristic signature can allow us to distinguish the effects of minihalos on intergalactic gas at times preceding and during reionization. We illustrate this effect with the example of 21 cm emission and absorption from redshifts during and before reionization. This effect can potentially allow us to probe physics on kpc scales using observations on 100 Mpc scales. We present sensitivity forecasts for FAST and Arecibo. Depending on parameters, this enhanced structure may be detectable by Arecibo at z ∼ 15−20, and with appropriate instrumentation FAST could measure the BAO power spectrum with high precision. In principle, this effect could also pose a serious challenge for efforts to constrain dark energy using observations of the BAO feature at low redshift.

  9. Large scale electromechanical transistor with application in mass sensing

    SciTech Connect (OSTI)

    Jin, Leisheng; Li, Lijie

    2014-12-07

    Nanomechanical transistor (NMT) has evolved from the single electron transistor, a device that operates by shuttling electrons with a self-excited central conductor. The unfavoured aspects of the NMT are the complexity of the fabrication process and its signal processing unit, which could potentially be overcome by designing much larger devices. This paper reports a new design of large scale electromechanical transistor (LSEMT), still taking advantage of the principle of shuttling electrons. However, because of the large size, nonlinear electrostatic forces induced by the transistor itself are not sufficient to drive the mechanical member into vibrationan external force has to be used. In this paper, a LSEMT device is modelled, and its new application in mass sensing is postulated using two coupled mechanical cantilevers, with one of them being embedded in the transistor. The sensor is capable of detecting added mass using the eigenstate shifts method by reading the change of electrical current from the transistor, which has much higher sensitivity than conventional eigenfrequency shift approach used in classical cantilever based mass sensors. Numerical simulations are conducted to investigate the performance of the mass sensor.

  10. Parallel Index and Query for Large Scale Data Analysis

    SciTech Connect (OSTI)

    Chou, Jerry; Wu, Kesheng; Ruebel, Oliver; Howison, Mark; Qiang, Ji; Prabhat,; Austin, Brian; Bethel, E. Wes; Ryne, Rob D.; Shoshani, Arie

    2011-07-18

    Modern scientific datasets present numerous data management and analysis challenges. State-of-the-art index and query technologies are critical for facilitating interactive exploration of large datasets, but numerous challenges remain in terms of designing a system for process- ing general scientific datasets. The system needs to be able to run on distributed multi-core platforms, efficiently utilize underlying I/O infrastructure, and scale to massive datasets. We present FastQuery, a novel software framework that address these challenges. FastQuery utilizes a state-of-the-art index and query technology (FastBit) and is designed to process mas- sive datasets on modern supercomputing platforms. We apply FastQuery to processing of a massive 50TB dataset generated by a large scale accelerator modeling code. We demonstrate the scalability of the tool to 11,520 cores. Motivated by the scientific need to search for inter- esting particles in this dataset, we use our framework to reduce search time from hours to tens of seconds.

  11. LARGE SCALE METHOD FOR THE PRODUCTION AND PURIFICATION OF CURIUM

    DOE Patents [OSTI]

    Higgins, G.H.; Crane, W.W.T.

    1959-05-19

    A large-scale process for production and purification of Cm/sup 242/ is described. Aluminum slugs containing Am are irradiated and declad in a NaOH-- NaHO/sub 3/ solution at 85 to 100 deg C. The resulting slurry filtered and washed with NaOH, NH/sub 4/OH, and H/sub 2/O. Recovery of Cm from filtrate and washings is effected by an Fe(OH)/sub 3/ precipitation. The precipitates are then combined and dissolved ln HCl and refractory oxides centrifuged out. These oxides are then fused with Na/sub 2/CO/sub 3/ and dissolved in HCl. The solution is evaporated and LiCl solution added. The Cm, rare earths, and anionic impurities are adsorbed on a strong-base anfon exchange resin. Impurities are eluted with LiCl--HCl solution, rare earths and Cm are eluted by HCl. Other ion exchange steps further purify the Cm. The Cm is then precipitated as fluoride and used in this form or further purified and processed. (T.R.H.)

  12. ANALYSIS OF TURBULENT MIXING JETS IN LARGE SCALE TANK

    SciTech Connect (OSTI)

    Lee, S; Richard Dimenna, R; Robert Leishear, R; David Stefanko, D

    2007-03-28

    Flow evolution models were developed to evaluate the performance of the new advanced design mixer pump for sludge mixing and removal operations with high-velocity liquid jets in one of the large-scale Savannah River Site waste tanks, Tank 18. This paper describes the computational model, the flow measurements used to provide validation data in the region far from the jet nozzle, the extension of the computational results to real tank conditions through the use of existing sludge suspension data, and finally, the sludge removal results from actual Tank 18 operations. A computational fluid dynamics approach was used to simulate the sludge removal operations. The models employed a three-dimensional representation of the tank with a two-equation turbulence model. Both the computational approach and the models were validated with onsite test data reported here and literature data. The model was then extended to actual conditions in Tank 18 through a velocity criterion to predict the ability of the new pump design to suspend settled sludge. A qualitative comparison with sludge removal operations in Tank 18 showed a reasonably good comparison with final results subject to significant uncertainties in actual sludge properties.

  13. Parallel I/O Software Infrastructure for Large-Scale Systems

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

    Parallel IO Software Infrastructure for Large-Scale Systems Parallel IO Software Infrastructure for Large-Scale Systems Choudhary.png An illustration of how MPI---IO file domain...

  14. I/O Performance of a Large-Scale, Interpreter-Driven Laser-Plasma...

    Office of Scientific and Technical Information (OSTI)

    Conference: IO Performance of a Large-Scale, Interpreter-Driven Laser-Plasma Interaction Code Citation Details In-Document Search Title: IO Performance of a Large-Scale, ...

  15. Comparison of the effects in the rock mass of large-scale chemical...

    Office of Scientific and Technical Information (OSTI)

    Comparison of the effects in the rock mass of large-scale chemical and nuclear explosions. ... Title: Comparison of the effects in the rock mass of large-scale chemical and nuclear ...

  16. Energy Department Awards $66.7 Million for Large-Scale Carbon...

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

    66.7 Million for Large-Scale Carbon Sequestration Project Energy Department Awards 66.7 Million for Large-Scale Carbon Sequestration Project December 18, 2007 - 4:58pm Addthis ...

  17. Large-Scale Deep Learning on the YFCC100M Dataset (Conference...

    Office of Scientific and Technical Information (OSTI)

    Conference: Large-Scale Deep Learning on the YFCC100M Dataset Citation Details In-Document Search Title: Large-Scale Deep Learning on the YFCC100M Dataset Authors: Ni, K ; Boakye, ...

  18. EERE Success Story-FEMP Helps Federal Facilities Develop Large-Scale

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

    Renewable Energy Projects | Department of Energy FEMP Helps Federal Facilities Develop Large-Scale Renewable Energy Projects EERE Success Story-FEMP Helps Federal Facilities Develop Large-Scale Renewable Energy Projects August 21, 2013 - 12:00am Addthis EERE's Federal Energy Management Program issued a new resource that provides best practices and helpful guidance for federal agencies developing large-scale renewable energy projects. The resource, Large-Scale Renewable Energy Guide:

  19. Large-Scale Spray Releases: Initial Aerosol Test Results

    SciTech Connect (OSTI)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Kurath, Dean E.; Adkins, Harold E.; Billing, Justin M.; Burns, Carolyn A.; Davis, James M.; Enderlin, Carl W.; Fischer, Christopher M.; Jenks, Jeromy WJ; Lukins, Craig D.; MacFarlan, Paul J.; Shutthanandan, Janani I.; Smith, Dennese M.

    2012-12-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  20. Large Scale Computing and Storage Requirements for Nuclear Physics Research

    SciTech Connect (OSTI)

    Gerber, Richard A.; Wasserman, Harvey J.

    2012-03-02

    IThe National Energy Research Scientific Computing Center (NERSC) is the primary computing center for the DOE Office of Science, serving approximately 4,000 users and hosting some 550 projects that involve nearly 700 codes for a wide variety of scientific disciplines. In addition to large-scale computing resources NERSC provides critical staff support and expertise to help scientists make the most efficient use of these resources to advance the scientific mission of the Office of Science. In May 2011, NERSC, DOE’s Office of Advanced Scientific Computing Research (ASCR) and DOE’s Office of Nuclear Physics (NP) held a workshop to characterize HPC requirements for NP research over the next three to five years. The effort is part of NERSC’s continuing involvement in anticipating future user needs and deploying necessary resources to meet these demands. The workshop revealed several key requirements, in addition to achieving its goal of characterizing NP computing. The key requirements include: 1. Larger allocations of computational resources at NERSC; 2. Visualization and analytics support; and 3. Support at NERSC for the unique needs of experimental nuclear physicists. This report expands upon these key points and adds others. The results are based upon representative samples, called “case studies,” of the needs of science teams within NP. The case studies were prepared by NP workshop participants and contain a summary of science goals, methods of solution, current and future computing requirements, and special software and support needs. Participants were also asked to describe their strategy for computing in the highly parallel, “multi-core” environment that is expected to dominate HPC architectures over the next few years. The report also includes a section with NERSC responses to the workshop findings. NERSC has many initiatives already underway that address key workshop findings and all of the action items are aligned with NERSC strategic plans.

  1. Large-Scale Data Challenges in Future Power Grids

    SciTech Connect (OSTI)

    Yin, Jian; Sharma, Poorva; Gorton, Ian; Akyol, Bora A.

    2013-03-25

    This paper describes technical challenges in supporting large-scale real-time data analysis for future power grid systems and discusses various design options to address these challenges. Even though the existing U.S. power grid has served the nation remarkably well over the last 120 years, big changes are in the horizon. The widespread deployment of renewable generation, smart grid controls, energy storage, plug-in hybrids, and new conducting materials will require fundamental changes in the operational concepts and principal components. The whole system becomes highly dynamic and needs constant adjustments based on real time data. Even though millions of sensors such as phase measurement units (PMUs) and smart meters are being widely deployed, a data layer that can support this amount of data in real time is needed. Unlike the data fabric in cloud services, the data layer for smart grids must address some unique challenges. This layer must be scalable to support millions of sensors and a large number of diverse applications and still provide real time guarantees. Moreover, the system needs to be highly reliable and highly secure because the power grid is a critical piece of infrastructure. No existing systems can satisfy all the requirements at the same time. We examine various design options. In particular, we explore the special characteristics of power grid data to meet both scalability and quality of service requirements. Our initial prototype can improve performance by orders of magnitude over existing general-purpose systems. The prototype was demonstrated with several use cases from PNNL’s FPGI and was shown to be able to integrate huge amount of data from a large number of sensors and a diverse set of applications.

  2. Primordial non-Gaussianity in the bispectra of large-scale structure

    SciTech Connect (OSTI)

    Tasinato, Gianmassimo; Tellarini, Matteo; Ross, Ashley J.; Wands, David E-mail: matteo.tellarini@port.ac.uk E-mail: david.wands@port.ac.uk

    2014-03-01

    The statistics of large-scale structure in the Universe can be used to probe non-Gaussianity of the primordial density field, complementary to existing constraints from the cosmic microwave background. In particular, the scale dependence of halo bias, which affects the halo distribution at large scales, represents a promising tool for analyzing primordial non-Gaussianity of local form. Future observations, for example, may be able to constrain the trispectrum parameter g{sub NL} that is difficult to study and constrain using the CMB alone. We investigate how galaxy and matter bispectra can distinguish between the two non-Gaussian parameters f{sub NL} and g{sub NL}, whose effects give nearly degenerate contributions to the power spectra. We use a generalization of the univariate bias approach, making the hypothesis that the number density of halos forming at a given position is a function of the local matter density contrast and of its local higher-order statistics. Using this approach, we calculate the halo-matter bispectra and analyze their properties. We determine a connection between the sign of the halo bispectrum on large scales and the parameter g{sub NL}. We also construct a combination of halo and matter bispectra that is sensitive to f{sub NL}, with little contamination from g{sub NL}. We study both the case of single and multiple sources to the primordial gravitational potential, discussing how to extend the concept of stochastic halo bias to the case of bispectra. We use a specific halo mass-function to calculate numerically the bispectra in appropriate squeezed limits, confirming our theoretical findings.

  3. Large Scale Computing and Storage Requirements for High Energy Physics

    SciTech Connect (OSTI)

    Gerber, Richard A.; Wasserman, Harvey

    2010-11-24

    The National Energy Research Scientific Computing Center (NERSC) is the leading scientific computing facility for the Department of Energy's Office of Science, providing high-performance computing (HPC) resources to more than 3,000 researchers working on about 400 projects. NERSC provides large-scale computing resources and, crucially, the support and expertise needed for scientists to make effective use of them. In November 2009, NERSC, DOE's Office of Advanced Scientific Computing Research (ASCR), and DOE's Office of High Energy Physics (HEP) held a workshop to characterize the HPC resources needed at NERSC to support HEP research through the next three to five years. The effort is part of NERSC's legacy of anticipating users needs and deploying resources to meet those demands. The workshop revealed several key points, in addition to achieving its goal of collecting and characterizing computing requirements. The chief findings: (1) Science teams need access to a significant increase in computational resources to meet their research goals; (2) Research teams need to be able to read, write, transfer, store online, archive, analyze, and share huge volumes of data; (3) Science teams need guidance and support to implement their codes on future architectures; and (4) Projects need predictable, rapid turnaround of their computational jobs to meet mission-critical time constraints. This report expands upon these key points and includes others. It also presents a number of case studies as representative of the research conducted within HEP. Workshop participants were asked to codify their requirements in this case study format, summarizing their science goals, methods of solution, current and three-to-five year computing requirements, and software and support needs. Participants were also asked to describe their strategy for computing in the highly parallel, multi-core environment that is expected to dominate HPC architectures over the next few years. The report includes

  4. Large-scale seismic waveform quality metric calculation using Hadoop

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

    Magana-Zook, Steven; Gaylord, Jessie M.; Knapp, Douglas R.; Dodge, Douglas A.; Ruppert, Stanley D.

    2016-05-27

    Here in this work we investigated the suitability of Hadoop MapReduce and Apache Spark for large-scale computation of seismic waveform quality metrics by comparing their performance with that of a traditional distributed implementation. The Incorporated Research Institutions for Seismology (IRIS) Data Management Center (DMC) provided 43 terabytes of broadband waveform data of which 5.1 TB of data were processed with the traditional architecture, and the full 43 TB were processed using MapReduce and Spark. Maximum performance of ~0.56 terabytes per hour was achieved using all 5 nodes of the traditional implementation. We noted that I/O dominated processing, and that I/Omore » performance was deteriorating with the addition of the 5th node. Data collected from this experiment provided the baseline against which the Hadoop results were compared. Next, we processed the full 43 TB dataset using both MapReduce and Apache Spark on our 18-node Hadoop cluster. We conducted these experiments multiple times with various subsets of the data so that we could build models to predict performance as a function of dataset size. We found that both MapReduce and Spark significantly outperformed the traditional reference implementation. At a dataset size of 5.1 terabytes, both Spark and MapReduce were about 15 times faster than the reference implementation. Furthermore, our performance models predict that for a dataset of 350 terabytes, Spark running on a 100-node cluster would be about 265 times faster than the reference implementation. We do not expect that the reference implementation deployed on a 100-node cluster would perform significantly better than on the 5-node cluster because the I/O performance cannot be made to scale. Finally, we note that although Big Data technologies clearly provide a way to process seismic waveform datasets in a high-performance and scalable manner, the technology is still rapidly changing, requires a high degree of investment in personnel, and will

  5. Ward identities and consistency relations for the large scale...

    Office of Scientific and Technical Information (OSTI)

    distribution of dark matter halos relative to that of the underlying dark matter field. ... Country of input: International Atomic Energy Agency (IAEA) Country of Publication: ...

  6. PROPERTIES IMPORTANT TO MIXING FOR WTP LARGE SCALE INTEGRATED TESTING

    SciTech Connect (OSTI)

    Koopman, D.; Martino, C.; Poirier, M.

    2012-04-26

    Large Scale Integrated Testing (LSIT) is being planned by Bechtel National, Inc. to address uncertainties in the full scale mixing performance of the Hanford Waste Treatment and Immobilization Plant (WTP). Testing will use simulated waste rather than actual Hanford waste. Therefore, the use of suitable simulants is critical to achieving the goals of the test program. External review boards have raised questions regarding the overall representativeness of simulants used in previous mixing tests. Accordingly, WTP requested the Savannah River National Laboratory (SRNL) to assist with development of simulants for use in LSIT. Among the first tasks assigned to SRNL was to develop a list of waste properties that matter to pulse-jet mixer (PJM) mixing of WTP tanks. This report satisfies Commitment 5.2.3.1 of the Department of Energy Implementation Plan for Defense Nuclear Facilities Safety Board Recommendation 2010-2: physical properties important to mixing and scaling. In support of waste simulant development, the following two objectives are the focus of this report: (1) Assess physical and chemical properties important to the testing and development of mixing scaling relationships; (2) Identify the governing properties and associated ranges for LSIT to achieve the Newtonian and non-Newtonian test objectives. This includes the properties to support testing of sampling and heel management systems. The test objectives for LSIT relate to transfer and pump out of solid particles, prototypic integrated operations, sparger operation, PJM controllability, vessel level/density measurement accuracy, sampling, heel management, PJM restart, design and safety margin, Computational Fluid Dynamics (CFD) Verification and Validation (V and V) and comparison, performance testing and scaling, and high temperature operation. The slurry properties that are most important to Performance Testing and Scaling depend on the test objective and rheological classification of the slurry (i

  7. Large-Scale First-Principles Molecular Dynamics Simulations with Electrostatic Embedding: Application to Acetylcholinesterase Catalysis

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

    Fattebert, Jean-Luc; Lau, Edmond Y.; Bennion, Brian J.; Huang, Patrick; Lightstone, Felice C.

    2015-10-22

    Enzymes are complicated solvated systems that typically require many atoms to simulate their function with any degree of accuracy. We have recently developed numerical techniques for large scale First-Principles molecular dynamics simulations and applied them to study the enzymatic reaction catalyzed by acetylcholinesterase. We carried out Density functional theory calculations for a quantum mechanical (QM) sub- system consisting of 612 atoms with an O(N) complexity finite-difference approach. The QM sub-system is embedded inside an external potential field representing the electrostatic effect due to the environment. We obtained finite temperature sampling by First-Principles molecular dynamics for the acylation reaction of acetylcholinemore » catalyzed by acetylcholinesterase. Our calculations shows two energies barriers along the reaction coordinate for the enzyme catalyzed acylation of acetylcholine. In conclusion, the second barrier (8.5 kcal/mole) is rate-limiting for the acylation reaction and in good agreement with experiment.« less

  8. Large-Scale First-Principles Molecular Dynamics Simulations with Electrostatic Embedding: Application to Acetylcholinesterase Catalysis

    SciTech Connect (OSTI)

    Fattebert, Jean-Luc; Lau, Edmond Y.; Bennion, Brian J.; Huang, Patrick; Lightstone, Felice C.

    2015-10-22

    Enzymes are complicated solvated systems that typically require many atoms to simulate their function with any degree of accuracy. We have recently developed numerical techniques for large scale First-Principles molecular dynamics simulations and applied them to study the enzymatic reaction catalyzed by acetylcholinesterase. We carried out Density functional theory calculations for a quantum mechanical (QM) sub- system consisting of 612 atoms with an O(N) complexity finite-difference approach. The QM sub-system is embedded inside an external potential field representing the electrostatic effect due to the environment. We obtained finite temperature sampling by First-Principles molecular dynamics for the acylation reaction of acetylcholine catalyzed by acetylcholinesterase. Our calculations shows two energies barriers along the reaction coordinate for the enzyme catalyzed acylation of acetylcholine. In conclusion, the second barrier (8.5 kcal/mole) is rate-limiting for the acylation reaction and in good agreement with experiment.

  9. GenASiS Basics: Object-oriented utilitarian functionality for large-scale physics simulations

    SciTech Connect (OSTI)

    Cardall, Christian Y.; Budiardja, Reuben D.

    2015-06-11

    Aside from numerical algorithms and problem setup, large-scale physics simulations on distributed-memory supercomputers require more basic utilitarian functionality, such as physical units and constants; display to the screen or standard output device; message passing; I/O to disk; and runtime parameter management and usage statistics. Here we describe and make available Fortran 2003 classes furnishing extensible object-oriented implementations of this sort of rudimentary functionality, along with individual `unit test' programs and larger example problems demonstrating their use. Lastly, these classes compose the Basics division of our developing astrophysics simulation code GenASiS (General Astrophysical Simulation System), but their fundamental nature makes them useful for physics simulations in many fields.

  10. GenASiS Basics: Object-oriented utilitarian functionality for large-scale physics simulations

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

    Cardall, Christian Y.; Budiardja, Reuben D.

    2015-06-11

    Aside from numerical algorithms and problem setup, large-scale physics simulations on distributed-memory supercomputers require more basic utilitarian functionality, such as physical units and constants; display to the screen or standard output device; message passing; I/O to disk; and runtime parameter management and usage statistics. Here we describe and make available Fortran 2003 classes furnishing extensible object-oriented implementations of this sort of rudimentary functionality, along with individual `unit test' programs and larger example problems demonstrating their use. Lastly, these classes compose the Basics division of our developing astrophysics simulation code GenASiS (General Astrophysical Simulation System), but their fundamental nature makes themmore » useful for physics simulations in many fields.« less

  11. PATHWAYS OF LARGE-SCALE MAGNETIC COUPLINGS BETWEEN SOLAR CORONAL EVENTS

    SciTech Connect (OSTI)

    Schrijver, Carolus J.; Title, Alan M.; DeRosa, Marc L.; Yeates, Anthony R.

    2013-08-20

    The high-cadence, comprehensive view of the solar corona by SDO/AIA shows many events that are widely separated in space while occurring close together in time. In some cases, sets of coronal events are evidently causally related, while in many other instances indirect evidence can be found. We present case studies to highlight a variety of coupling processes involved in coronal events. We find that physical linkages between events do occur, but concur with earlier studies that these couplings appear to be crucial to understanding the initiation of major eruptive or explosive phenomena relatively infrequently. We note that the post-eruption reconfiguration timescale of the large-scale corona, estimated from the extreme-ultraviolet afterglow, is on average longer than the mean time between coronal mass ejections (CMEs), so that many CMEs originate from a corona that is still adjusting from a previous event. We argue that the coronal field is intrinsically global: current systems build up over days to months, the relaxation after eruptions continues over many hours, and evolving connections easily span much of a hemisphere. This needs to be reflected in our modeling of the connections from the solar surface into the heliosphere to properly model the solar wind, its perturbations, and the generation and propagation of solar energetic particles. However, the large-scale field cannot be constructed reliably by currently available observational resources. We assess the potential of high-quality observations from beyond Earth's perspective and advanced global modeling to understand the couplings between coronal events in the context of CMEs and solar energetic particle events.

  12. Locations of Smart Grid Demonstration and Large-Scale Energy Storage

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

    Projects | Department of Energy Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects Map of the United States showing the location of all projects created with funding from the Smart Grid Demonstration and Energy Storage Project, funded through the American Recovery and Reinvestment Act. Locations of Smart Grid Demonstration and Large-Scale Energy Storage Projects (90.94 KB) More Documents

  13. Large-scale Offshore Wind Power in the United States. Assessment of Opportunities and Barriers

    SciTech Connect (OSTI)

    Musial, Walter; Ram, Bonnie

    2010-09-01

    This report describes the benefits of and barriers to large-scale deployment of offshore wind energy systems in U.S. waters.

  14. Asynchronous Two-Level Checkpointing Scheme for Large-Scale Adjoints...

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

    researchLANSeventslistn Adjoints are an important computational tool for large-scale sensitivity evaluation, uncertainty quantification, and derivative-based...

  15. DOE's Office of Science Seeks Proposals for Expanded Large-Scale...

    Office of Environmental Management (EM)

    Seeks Proposals for Expanded Large-Scale Scientific Computing DOE's Office of Science ... Successful proposers will be given the use of substantial computer time and data storage ...

  16. Large-scale delamination of multi-layers transition metal carbides...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Large-scale ... Herein we report on a general approach to delaminate ... Type: Accepted Manuscript Journal Name: Dalton Transactions ...

  17. A Large-Scale, High-Resolution Hydrological Model Parameter Data...

    Office of Scientific and Technical Information (OSTI)

    Large-Scale, High-Resolution Hydrological Model Parameter Data Set for Climate Change Impact Assessment for the Conterminous US Citation Details In-Document Search Title: A ...

  18. HyLights -- Tools to Prepare the Large-Scale European Demonstration...

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

    Projects on Hydrogen for Transport HyLights -- Tools to Prepare the Large-Scale European Demonstration Projects on Hydrogen for Transport Presented at Refueling ...

  19. Development of fine-resolution analyses and expanded large-scale...

    Office of Scientific and Technical Information (OSTI)

    II: Scale-awareness and application to single-column model experiments Title: Development of fine-resolution analyses and expanded large-scale forcing properties. Part II: ...

  20. Development of fine-resolution analyses and expanded large-scale...

    Office of Scientific and Technical Information (OSTI)

    I: Methodology and evaluation Citation Details In-Document Search Title: Development of fine-resolution analyses and expanded large-scale forcing properties. Part I: Methodology ...

  1. Oil geochemistry study; Blocks III and IV Bachaquedro Field, Lake Maracaibo, Venezuela

    SciTech Connect (OSTI)

    Patterson, B.A.; Villarroel, H.G. de; Rondon, L.

    1996-08-01

    Blocks III and IV Bachaquero, Field, located on the east side of Lake Maracaibo, comprise an area of 40 square kilometers. In 1956 the discovery well penetrated oil saturated sands in a south dipping homoclinal structure. In 1958 production reached a maximum of 245,000 barrels per day of moderate gravity oil from three Miocene age Lagunillas Formation sands, designated as L, M, and N. The Bachaquero Field has experienced production problems including high gas-oil ratios from M and N sands to the north, high water cuts in all three sands to the south, and low production rates in the southeast. In addition, the vertical and lateral continuity of the oil pools are unknown. High resolution gas chromatography and analysis of biological markers was employed in order to resolve the continuity of the oil pools, determine genetic origin of the oils, and shed light on erratic production. Oil in the L sands are vertically discontinuous from oil in the M+N sands. The two oil pools appear laterally continuous within the study area, indicating absence of fault barriers. Well VLD 311, open to both L and M sands, produces a mix of oils, but with a strong contribution from the M sand. Bachaquero Field reservoirs were charged with oil from two different facies of the Upper Cretaceous La Luna or perhaps from La Luna and Colon source rocks as the stratigraphically younger L sands contain less mature oil with a stronger terrigenous imprint than oil the M and N sands.

  2. Large-scale computations in analysis of structures

    SciTech Connect (OSTI)

    McCallen, D.B.; Goudreau, G.L.

    1993-09-01

    Computer hardware and numerical analysis algorithms have progressed to a point where many engineering organizations and universities can perform nonlinear analyses on a routine basis. Through much remains to be done in terms of advancement of nonlinear analysis techniques and characterization on nonlinear material constitutive behavior, the technology exists today to perform useful nonlinear analysis for many structural systems. In the current paper, a survey on nonlinear analysis technologies developed and employed for many years on programmatic defense work at the Lawrence Livermore National Laboratory is provided, and ongoing nonlinear numerical simulation projects relevant to the civil engineering field are described.

  3. Large scale condensed matter and fluid dynamics simulations | Argonne

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

    Leadership Computing Facility , (a)Snapshots of the vorticity field of a UPO located in weakly turbulent flow with Re=371 and period equal to 26864 LB time steps. The quantity shown is the magnitude of vorticity above a given cut-off level. Red corresponds to large negative vorticity (clockwise rotation), and blue to large positive vorticity (counter-clockwise rotation). (b)Initial stucture of the large LDH-nucleic acid models, (a) System, at the start of the simulation. For clarity, water

  4. Design advanced for large-scale, economic, floating LNG plant

    SciTech Connect (OSTI)

    Naklie, M.M.

    1997-06-30

    A floating LNG plant design has been developed which is technically feasible, economical, safe, and reliable. This technology will allow monetization of small marginal fields and improve the economics of large fields. Mobil`s world-scale plant design has a capacity of 6 million tons/year of LNG and up to 55,000 b/d condensate produced from 1 bcfd of feed gas. The plant would be located on a large, secure, concrete barge with a central moonpool. LNG storage is provided for 250,000 cu m and condensate storage for 650,000 bbl. And both products are off-loaded from the barge. Model tests have verified the stability of the barge structure: barge motions are low enough to permit the plant to continue operation in a 100-year storm in the Pacific Rim. Moreover, the barge is spread-moored, eliminating the need for a turret and swivel. Because the design is generic, the plant can process a wide variety of feed gases and operate in different environments, should the plant be relocated. This capability potentially gives the plant investment a much longer project life because its use is not limited to the life of only one producing area.

  5. Large-scale soil bioremediation using white-rot fungi

    SciTech Connect (OSTI)

    Holroyd, M.L.; Caunt, P.

    1995-12-31

    Some organic pollutant compounds are considered resistant to conventional bioremediation because of their structure or behavior in soil. This phenomenon, together with the increasing need to reach lower target levels in shorter time periods, has shown the need for improved or alternative biological processes. It has been known for some time that the white-rot fungi, particularly the species Phanerochaete chrysosporium, have potentially useful abilities to rapidly degrade pollutant molecules. The use of white-rot fungi at the field scale presents a number of challenges, and this paper outlines the use of a process incorporating Phanerochaete to successfully bioremediate over 6,000 m{sup 3} of chlorophenol-contaminated soil at a site in Finland. Moreover, the method developed is very cost-effective and proved capable of reaching the very low target levels within the contracted time span.

  6. Zero discharge and large-scale DCS are plant highlights

    SciTech Connect (OSTI)

    Solar, R.

    1995-04-01

    This article reports that the Mulberry cogeneration facility has several features that make it notable in the power field. A zero-discharge wastewater system, an inlet-air chilling system, a secondary boiler, and an extensive distributed-control system (DCS) for overall plant operation are examples. Ability to meet the two-stage NO{sub x}-emission limits -- 25 ppm during the first three years and 15 ppm thereafter -- is a unique challenge. The plant design allows the lower limit to be met now, and retrofit with different burners is possible if NO{sub x}-emission limits are tightened later. The facility, near Bartow in Polk County, Fla, is owned by Polk Power Partners LP, whose members include Central and South West Energy Inc (CSW) of Dallas and ARK Energy of Laguna Hills, Calif. The operating company, CSW Operations, is a subsidiary of CSW. Heart of the plant is a single gas-turbine (GT)/HRSG/steam-turbine combined cycle, providing electric power to Tampa Electric Co and Florida Power Corp, with up to 25,000 lb/hr of process steam for an adjacent ethanol plant which was developed by the facility`s partnership. Commercial operation of Mulberry began on Sept 2, 1994.

  7. Large-Scale Continuous Subgraph Queries on Streams

    SciTech Connect (OSTI)

    Choudhury, Sutanay; Holder, Larry; Chin, George; Feo, John T.

    2011-11-30

    Graph pattern matching involves finding exact or approximate matches for a query subgraph in a larger graph. It has been studied extensively and has strong applications in domains such as computer vision, computational biology, social networks, security and finance. The problem of exact graph pattern matching is often described in terms of subgraph isomorphism which is NP-complete. The exponential growth in streaming data from online social networks, news and video streams and the continual need for situational awareness motivates a solution for finding patterns in streaming updates. This is also the prime driver for the real-time analytics market. Development of incremental algorithms for graph pattern matching on streaming inputs to a continually evolving graph is a nascent area of research. Some of the challenges associated with this problem are the same as found in continuous query (CQ) evaluation on streaming databases. This paper reviews some of the representative work from the exhaustively researched field of CQ systems and identifies important semantics, constraints and architectural features that are also appropriate for HPC systems performing real-time graph analytics. For each of these features we present a brief discussion of the challenge encountered in the database realm, the approach to the solution and state their relevance in a high-performance, streaming graph processing framework.

  8. Development of explosive event scale model testing capability at Sandia`s large scale centrifuge facility

    SciTech Connect (OSTI)

    Blanchat, T.K.; Davie, N.T.; Calderone, J.J.

    1998-02-01

    Geotechnical structures such as underground bunkers, tunnels, and building foundations are subjected to stress fields produced by the gravity load on the structure and/or any overlying strata. These stress fields may be reproduced on a scaled model of the structure by proportionally increasing the gravity field through the use of a centrifuge. This technology can then be used to assess the vulnerability of various geotechnical structures to explosive loading. Applications of this technology include assessing the effectiveness of earth penetrating weapons, evaluating the vulnerability of various structures, counter-terrorism, and model validation. This document describes the development of expertise in scale model explosive testing on geotechnical structures using Sandia`s large scale centrifuge facility. This study focused on buried structures such as hardened storage bunkers or tunnels. Data from this study was used to evaluate the predictive capabilities of existing hydrocodes and structural dynamics codes developed at Sandia National Laboratories (such as Pronto/SPH, Pronto/CTH, and ALEGRA). 7 refs., 50 figs., 8 tabs.

  9. Multilevel method for modeling large-scale networks.

    SciTech Connect (OSTI)

    Safro, I. M.

    2012-02-24

    Understanding the behavior of real complex networks is of great theoretical and practical significance. It includes developing accurate artificial models whose topological properties are similar to the real networks, generating the artificial networks at different scales under special conditions, investigating a network dynamics, reconstructing missing data, predicting network response, detecting anomalies and other tasks. Network generation, reconstruction, and prediction of its future topology are central issues of this field. In this project, we address the questions related to the understanding of the network modeling, investigating its structure and properties, and generating artificial networks. Most of the modern network generation methods are based either on various random graph models (reinforced by a set of properties such as power law distribution of node degrees, graph diameter, and number of triangles) or on the principle of replicating an existing model with elements of randomization such as R-MAT generator and Kronecker product modeling. Hierarchical models operate at different levels of network hierarchy but with the same finest elements of the network. However, in many cases the methods that include randomization and replication elements on the finest relationships between network nodes and modeling that addresses the problem of preserving a set of simplified properties do not fit accurately enough the real networks. Among the unsatisfactory features are numerically inadequate results, non-stability of algorithms on real (artificial) data, that have been tested on artificial (real) data, and incorrect behavior at different scales. One reason is that randomization and replication of existing structures can create conflicts between fine and coarse scales of the real network geometry. Moreover, the randomization and satisfying of some attribute at the same time can abolish those topological attributes that have been undefined or hidden from

  10. Systematic theoretical investigation of the zero-field splitting in Gd(III) complexes: Wave function and density functional approaches

    SciTech Connect (OSTI)

    Khan, Shehryar Odelius, Michael; Kubica-Misztal, Aleksandra; Kruk, Danuta; Kowalewski, Jozef

    2015-01-21

    The zero-field splitting (ZFS) of the electronic ground state in paramagnetic ions is a sensitive probe of the variations in the electronic and molecular structure with an impact on fields ranging from fundamental physical chemistry to medical applications. A detailed analysis of the ZFS in a series of symmetric Gd(III) complexes is presented in order to establish the applicability and accuracy of computational methods using multiconfigurational complete-active-space self-consistent field wave functions and of density functional theory calculations. The various computational schemes are then applied to larger complexes Gd(III)DOTA(H{sub 2}O){sup −}, Gd(III)DTPA(H{sub 2}O){sup 2−}, and Gd(III)(H{sub 2}O){sub 8}{sup 3+} in order to analyze how the theoretical results compare to experimentally derived parameters. In contrast to approximations based on density functional theory, the multiconfigurational methods produce results for the ZFS of Gd(III) complexes on the correct order of magnitude.

  11. Plasma turbulence driven by transversely large-scale standing shear Alfven waves

    SciTech Connect (OSTI)

    Singh, Nagendra; Rao, Sathyanarayan

    2012-12-15

    Using two-dimensional particle-in-cell simulations, we study generation of turbulence consisting of transversely small-scale dispersive Alfven and electrostatic waves when plasma is driven by a large-scale standing shear Alfven wave (LS-SAW). The standing wave is set up by reflecting a propagating LS-SAW. The ponderomotive force of the standing wave generates transversely large-scale density modifications consisting of density cavities and enhancements. The drifts of the charged particles driven by the ponderomotive force and those directly caused by the fields of the standing LS-SAW generate non-thermal features in the plasma. Parametric instabilities driven by the inherent plasma nonlinearities associated with the LS-SAW in combination with the non-thermal features generate small-scale electromagnetic and electrostatic waves, yielding a broad frequency spectrum ranging from below the source frequency of the LS-SAW to ion cyclotron and lower hybrid frequencies and beyond. The power spectrum of the turbulence has peaks at distinct perpendicular wave numbers (k{sub Up-Tack }) lying in the range d{sub e}{sup -1}-6d{sub e}{sup -1}, d{sub e} being the electron inertial length, suggesting non-local parametric decay from small to large k{sub Up-Tack }. The turbulence spectrum encompassing both electromagnetic and electrostatic fluctuations is also broadband in parallel wave number (k{sub ||}). In a standing-wave supported density cavity, the ratio of the perpendicular electric to magnetic field amplitude is R(k{sub Up-Tack }) = |E{sub Up-Tack }(k{sub Up-Tack })/|B{sub Up-Tack }(k{sub Up-Tack })| Much-Less-Than V{sub A} for k{sub Up-Tack }d{sub e} < 0.5, where V{sub A} is the Alfven velocity. The characteristic features of the broadband plasma turbulence are compared with those available from satellite observations in space plasmas.

  12. A Semi-Analytical Solution for Large-Scale Injection-Induced...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: A Semi-Analytical Solution for Large-Scale Injection-Induced PressurePerturbation and Leakage in a Laterally Bounded Aquifer-AquitardSystem Citation Details ...

  13. DOE's Office of Science Seeks Proposals for Expanded Large-Scale Scientific Computing

    Broader source: Energy.gov [DOE]

    WASHINGTON, D.C. -- Secretary of Energy Samuel W. Bodman announced today that DOE’s Office of Science is seeking proposals to support innovative, large-scale computational science projects to...

  14. FEMP Helps Federal Facilities Develop Large-Scale Renewable Energy Projects

    Broader source: Energy.gov [DOE]

    FEMP developed a guide to help federal agencies, as well as the developers and financiers that work with them, to successfully install large-scale renewable energy projects at federal facilities.

  15. Development of fine-resolution analyses and expanded large-scale...

    Office of Scientific and Technical Information (OSTI)

    II: Scale-awareness and application to single-column model experiments Citation Details In-Document Search Title: Development of fine-resolution analyses and expanded large-scale ...

  16. ARM - Field Campaign - DigiCORA-III transition and AIRS preparation IOP

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

    govCampaignsDigiCORA-III transition and AIRS preparation IOP ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : DigiCORA-III transition and AIRS preparation IOP 2002.06.17 - 2002.07.31 Lead Scientist : Barry Lesht For data sets, see below. Abstract We will install the digiCORA-III at the SGP. In addition, we will monitor regular production (digiCORAII) soundings to collect a set of sounding data files to

  17. HyLights -- Tools to Prepare the Large-Scale European Demonstration

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

    Projects on Hydrogen for Transport | Department of Energy HyLights -- Tools to Prepare the Large-Scale European Demonstration Projects on Hydrogen for Transport HyLights -- Tools to Prepare the Large-Scale European Demonstration Projects on Hydrogen for Transport Presented at Refueling Infrastructure for Alternative Fuel Vehicles: Lessons Learned for Hydrogen Conference, April 2-3, 2008, Sacramento, California buenger.pdf (1.96 MB) More Documents & Publications Santa Clara Valley

  18. Reducing Data Center Loads for a Large-Scale, Net Zero Office Building |

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

    Department of Energy Reducing Data Center Loads for a Large-Scale, Net Zero Office Building Reducing Data Center Loads for a Large-Scale, Net Zero Office Building Document describes the design, implementation strategies, and continuous performance monitoring of the National Renewable Energy Laboratory's Research Support Facility data center. Download the case study. (3.03 MB) More Documents & Publications Top ECMs for Labs and Data Centers Best Practices Guide for Energy-Efficient Data

  19. Transport Induced by Large Scale Convective Structures in a Dipole-Confined Plasma

    SciTech Connect (OSTI)

    Grierson, B. A.; Mauel, M. E.; Worstell, M. W.; Klassen, M.

    2010-11-12

    Convective structures characterized by ExB motion are observed in a dipole-confined plasma. Particle transport rates are calculated from density dynamics obtained from multipoint measurements and the reconstructed electrostatic potential. The calculated transport rates determined from the large-scale dynamics and local probe measurements agree in magnitude, show intermittency, and indicate that the particle transport is dominated by large-scale convective structures.

  20. A First Step towards Large-Scale Plants to Plastics Engineering |

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

    Department of Energy A First Step towards Large-Scale Plants to Plastics Engineering A First Step towards Large-Scale Plants to Plastics Engineering November 9, 2010 - 1:56pm Addthis Brookhaven National Laboratory researches making plastics from plants. Niketa Kumar Niketa Kumar Public Affairs Specialist, Office of Public Affairs What does this mean for me? By optimizing the accumulation of particular fatty acids, a Brookhaven team of scientists are developing a method suitable for

  1. Large Scale GSHP as Alternative Energy for American Farmers | Department of

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

    Energy Large Scale GSHP as Alternative Energy for American Farmers Large Scale GSHP as Alternative Energy for American Farmers Project objectives: 100% replacement of on-site fossil fuel in the poultry farm; Reduce heating cost by 70% through bar efficiency improvement, GSHP and solar applications; Reduce 4% of mortality through cooling effect of GSHP in summer. gshp_xu_gshp_farmers.pdf (276.4 KB) More Documents & Publications Analysis of Energy, Environmental and Life Cycle Cost

  2. Large-Scale Urban Decontamination; Developments, Historical Examples and Lessons Learned

    SciTech Connect (OSTI)

    Rick Demmer

    2007-02-01

    Recent terrorist threats and actual events have lead to a renewed interest in the technical field of large scale, urban environment decontamination. One of the driving forces for this interest is the real potential for the cleanup and removal of radioactive dispersal device (RDD or dirty bomb) residues. In response the U. S. Government has spent many millions of dollars investigating RDD contamination and novel decontamination methodologies. Interest in chemical and biological (CB) cleanup has also peaked with the threat of terrorist action like the anthrax attack at the Hart Senate Office Building and with catastrophic natural events such as Hurricane Katrina. The efficiency of cleanup response will be improved with these new developments and a better understanding of the old reliable methodologies. Perhaps the most interesting area of investigation for large area decontamination is that of the RDD. While primarily an economic and psychological weapon, the need to cleanup and return valuable or culturally significant resources to the public is nonetheless valid. Several private companies, universities and National Laboratories are currently developing novel RDD cleanup technologies. Because of its longstanding association with radioactive facilities, the U. S. Department of Energy National Laboratories are at the forefront in developing and testing new RDD decontamination methods. However, such cleanup technologies are likely to be fairly task specific; while many different contamination mechanisms, substrate and environmental conditions will make actual application more complicated. Some major efforts have also been made to model potential contamination, to evaluate both old and new decontamination techniques and to assess their readiness for use. Non-radioactive, CB threats each have unique decontamination challenges and recent events have provided some examples. The U. S. Environmental Protection Agency (EPA), as lead agency for these emergency cleanup

  3. Using calibrated engineering models to predict energy savings in large-scale geothermal heat pump projects

    SciTech Connect (OSTI)

    Shonder, J.A.; Hughes, P.J.; Thornton, J.W.

    1998-10-01

    Energy savings performance contracting (ESPC) is now receiving greater attention as a means of implementing large-scale energy conservation projects in housing. Opportunities for such projects exist for military housing, federally subsidized low-income housing, and planned communities (condominiums, townhomes, senior centers), to name a few. Accurate prior (to construction) estimates of the energy savings in these projects reduce risk, decrease financing costs, and help avoid post-construction disputes over performance contract baseline adjustments. This paper demonstrates an improved method of estimating energy savings before construction takes place. Using an engineering model calibrated to pre-construction energy-use data collected in the field, this method is able to predict actual energy savings to a high degree of accuracy. This is verified with post-construction energy-use data from a geothermal heat pump ESPC at Fort Polk, Louisiana. This method also allows determination of the relative impact of the various energy conservation measures installed in a comprehensive energy conservation project. As an example, the breakout of savings at Fort Polk for the geothermal heat pumps, desuperheaters, lighting retrofits, and low-flow hot water outlets is provided.

  4. Using Calibrated Engineering Models To Predict Energy Savings In Large-Scale Geothermal Heat Pump Projects

    SciTech Connect (OSTI)

    Shonder, John A; Hughes, Patrick; Thornton, Jeff W.

    1998-01-01

    Energy savings performance contracting (ESPC) is now receiving greater attention as a means of implementing large-scale energy conservation projects in housing. Opportunities for such projects exist for military housing, federally subsidized low-income housing, and planned communities (condominiums, townhomes, senior centers), to name a few. Accurate prior (to construction) estimates of the energy savings in these projects reduce risk, decrease financing costs, and help avoid post-construction disputes over performance contract baseline adjustments. This paper demonstrates an improved method of estimating energy savings before construction takes place. Using an engineering model calibrated to pre-construction energy-use data collected in the field, this method is able to predict actual energy savings to a high degree of accuracy. This is verified with post-construction energy-use data from a geothermal heat pump ESPC at Fort Polk, Louisiana. This method also allows determination of the relative impact of the various energy conservation measures installed in a comprehensive energy conservation project. As an example, the breakout of savings at Fort Polk for the geothermal heat pumps, desuperheaters, lighting retrofits, and low-flow hot water outlets is provided.

  5. Fluorescence enhancement in large-scale self-assembled gold nanoparticle double arrays

    SciTech Connect (OSTI)

    Chekini, M.; Bierwagen, J.; Cunningham, A.; Bürgi, T.; Filter, R.; Rockstuhl, C.

    2015-12-21

    Localized surface plasmon resonances excited in metallic nanoparticles confine and enhance electromagnetic fields at the nanoscale. This is particularly pronounced in dimers made from two closely spaced nanoparticles. When quantum emitters, such as dyes, are placed in the gap of those dimers, their absorption and emission characteristics can be modified. Both processes have to be considered when aiming to enhance the fluorescence from the quantum emitters. This is particularly challenging for dimers, since the electromagnetic properties and the enhanced fluorescence sensitively depend on the distance between the nanoparticles. Here, we use a layer-by-layer method to precisely control the distances in such systems. We consider a dye layer deposited on top of an array of gold nanoparticles or integrated into a central position of a double array of gold nanoparticles. We study the effect of the spatial arrangement and the average distance on the plasmon-enhanced fluorescence. We found a maximum of a 99-fold increase in the fluorescence intensity of the dye layer sandwiched between two gold nanoparticle arrays. The interaction of the dye layer with the plasmonic system also causes a spectral shift in the emission wavelengths and a shortening of the fluorescence life times. Our work paves the way for large-scale, high throughput, and low-cost self-assembled functionalized plasmonic systems that can be used as efficient light sources.

  6. DGDFT: A massively parallel method for large scale density functional theory calculations

    SciTech Connect (OSTI)

    Hu, Wei Yang, Chao; Lin, Lin

    2015-09-28

    We describe a massively parallel implementation of the recently developed discontinuous Galerkin density functional theory (DGDFT) method, for efficient large-scale Kohn-Sham DFT based electronic structure calculations. The DGDFT method uses adaptive local basis (ALB) functions generated on-the-fly during the self-consistent field iteration to represent the solution to the Kohn-Sham equations. The use of the ALB set provides a systematic way to improve the accuracy of the approximation. By using the pole expansion and selected inversion technique to compute electron density, energy, and atomic forces, we can make the computational complexity of DGDFT scale at most quadratically with respect to the number of electrons for both insulating and metallic systems. We show that for the two-dimensional (2D) phosphorene systems studied here, using 37 basis functions per atom allows us to reach an accuracy level of 1.3 × 10{sup −4} Hartree/atom in terms of the error of energy and 6.2 × 10{sup −4} Hartree/bohr in terms of the error of atomic force, respectively. DGDFT can achieve 80% parallel efficiency on 128,000 high performance computing cores when it is used to study the electronic structure of 2D phosphorene systems with 3500-14 000 atoms. This high parallel efficiency results from a two-level parallelization scheme that we will describe in detail.

  7. LARGE-SCALE EXTREME-ULTRAVIOLET DISTURBANCES ASSOCIATED WITH A LIMB CORONAL MASS EJECTION

    SciTech Connect (OSTI)

    Dai, Y.; Auchere, F.; Vial, J.-C.; Tang, Y. H.; Zong, W. G.

    2010-01-10

    We present composite observations of a coronal mass ejection (CME) and the associated large-scale extreme-ultraviolet (EUV) disturbances on 2007 December 31 by the Extreme-ultraviolet Imager (EUVI) and COR1 coronagraph on board the recent Solar Terrestrial Relations Observatory mission. For this limb event, the EUV disturbances exhibit some typical characteristics of EUV Imaging Telescope waves: (1) in the 195 A bandpass, diffuse brightenings are observed propagating oppositely away from the flare site with a velocity of approx260 km s{sup -1}, leaving dimmings behind; (2) when the brightenings encounter the boundary of a polar coronal hole, they stop there to form a stationary front. Multi-temperature analysis of the propagating EUV disturbances favors a heating process over a density enhancement in the disturbance region. Furthermore, the EUVI-COR1 composite display shows unambiguously that the propagation of the diffuse brightenings coincides with a large lateral expansion of the CME, which consequently results in a double-loop-structured CME leading edge. Based on these observational facts, we suggest that the wave-like EUV disturbances are a result of magnetic reconfiguration related to the CME liftoff rather than true waves in the corona. Reconnections between the expanding CME magnetic field lines and surrounding quiet-Sun magnetic loops account for the propagating diffuse brightenings; dimmings appear behind them as a consequence of volume expansion. X-ray and radio data provide us with complementary evidence.

  8. Induced core formation time in subcritical magnetic clouds by large-scale trans-Alfvnic flows

    SciTech Connect (OSTI)

    Kudoh, Takahiro; Basu, Shantanu E-mail: basu@uwo.ca

    2014-10-20

    We clarify the mechanism of accelerated core formation by large-scale nonlinear flows in subcritical magnetic clouds by finding a semi-analytical formula for the core formation time and describing the physical processes that lead to them. Recent numerical simulations show that nonlinear flows induce rapid ambipolar diffusion that leads to localized supercritical regions that can collapse. Here, we employ non-ideal magnetohydrodynamic simulations including ambipolar diffusion for gravitationally stratified sheets threaded by vertical magnetic fields. One of the horizontal dimensions is eliminated, resulting in a simpler two-dimensional simulation that can clarify the basic process of accelerated core formation. A parameter study of simulations shows that the core formation time is inversely proportional to the square of the flow speed when the flow speed is greater than the Alfvn speed. We find a semi-analytical formula that explains this numerical result. The formula also predicts that the core formation time is about three times shorter than that with no turbulence, when the turbulent speed is comparable to the Alfvn speed.

  9. Kinematic morphology of large-scale structure: evolution from potential to rotational flow

    SciTech Connect (OSTI)

    Wang, Xin; Szalay, Alex; Aragn-Calvo, Miguel A.; Neyrinck, Mark C.; Eyink, Gregory L.

    2014-09-20

    As an alternative way to describe the cosmological velocity field, we discuss the evolution of rotational invariants constructed from the velocity gradient tensor. Compared with the traditional divergence-vorticity decomposition, these invariants, defined as coefficients of the characteristic equation of the velocity gradient tensor, enable a complete classification of all possible flow patterns in the dark-matter comoving frame, including both potential and vortical flows. We show that this tool, first introduced in turbulence two decades ago, is very useful for understanding the evolution of the cosmic web structure, and in classifying its morphology. Before shell crossing, different categories of potential flow are highly associated with the cosmic web structure because of the coherent evolution of density and velocity. This correspondence is even preserved at some level when vorticity is generated after shell crossing. The evolution from the potential to vortical flow can be traced continuously by these invariants. With the help of this tool, we show that the vorticity is generated in a particular way that is highly correlated with the large-scale structure. This includes a distinct spatial distribution and different types of alignment between the cosmic web and vorticity direction for various vortical flows. Incorporating shell crossing into closed dynamical systems is highly non-trivial, but we propose a possible statistical explanation for some of the phenomena relating to the internal structure of the three-dimensional invariant space.

  10. Large-Scale Renewable Energy Guide: Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities

    Broader source: Energy.gov [DOE]

    The Large-Scale Renewable Energy Guide: Developing Renewable Energy Projects Larger Than 10 MWs at Federal Facilities provides best practices and other helpful guidance for federal agencies developing large-scale renewable energy projects.

  11. Development of fine-resolution analyses and expanded large-scale forcing properties. Part I: Methodology and evaluation

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

    Li, Zhijin; Vogelmann, Andrew M.; Feng, Sha; Liu, Yangang; Lin, Wuyin; Zhang, Minghua; Toto, Tami; Endo, Satoshi

    2015-01-20

    We produce fine-resolution, three-dimensional fields of meteorological and other variables for the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Southern Great Plains site. The Community Gridpoint Statistical Interpolation system is implemented in a multiscale data assimilation (MS-DA) framework that is used within the Weather Research and Forecasting model at a cloud-resolving resolution of 2 km. The MS-DA algorithm uses existing reanalysis products and constrains fine-scale atmospheric properties by assimilating high-resolution observations. A set of experiments show that the data assimilation analysis realistically reproduces the intensity, structure, and time evolution of clouds and precipitation associated with a mesoscale convective system.more » Evaluations also show that the large-scale forcing derived from the fine-resolution analysis has an overall accuracy comparable to the existing ARM operational product. For enhanced applications, the fine-resolution fields are used to characterize the contribution of subgrid variability to the large-scale forcing and to derive hydrometeor forcing, which are presented in companion papers.« less

  12. What Will the Neighbors Think? Building Large-Scale Science Projects Around the World

    ScienceCinema (OSTI)

    Jones, Craig; Mrotzek, Christian; Toge, Nobu; Sarno, Doug

    2010-01-08

    Public participation is an essential ingredient for turning the International Linear Collider into a reality. Wherever the proposed particle accelerator is sited in the world, its neighbors -- in any country -- will have something to say about hosting a 35-kilometer-long collider in their backyards. When it comes to building large-scale physics projects, almost every laboratory has a story to tell. Three case studies from Japan, Germany and the US will be presented to examine how community relations are handled in different parts of the world. How do particle physics laboratories interact with their local communities? How do neighbors react to building large-scale projects in each region? How can the lessons learned from past experiences help in building the next big project? These and other questions will be discussed to engage the audience in an active dialogue about how a large-scale project like the ILC can be a good neighbor.

  13. Copy of Using Emulation and Simulation to Understand the Large-Scale Behavior of the Internet.

    SciTech Connect (OSTI)

    Adalsteinsson, Helgi; Armstrong, Robert C.; Chiang, Ken; Gentile, Ann C.; Lloyd, Levi; Minnich, Ronald G.; Vanderveen, Keith; Van Randwyk, Jamie A; Rudish, Don W.

    2008-10-01

    We report on the work done in the late-start LDRDUsing Emulation and Simulation toUnderstand the Large-Scale Behavior of the Internet. We describe the creation of a researchplatform that emulates many thousands of machines to be used for the study of large-scale inter-net behavior. We describe a proof-of-concept simple attack we performed in this environment.We describe the successful capture of a Storm bot and, from the study of the bot and furtherliterature search, establish large-scale aspects we seek to understand via emulation of Storm onour research platform in possible follow-on work. Finally, we discuss possible future work.3

  14. Report of the Workshop on Petascale Systems Integration for LargeScale Facilities

    SciTech Connect (OSTI)

    Kramer, William T.C.; Walter, Howard; New, Gary; Engle, Tom; Pennington, Rob; Comes, Brad; Bland, Buddy; Tomlison, Bob; Kasdorf, Jim; Skinner, David; Regimbal, Kevin

    2007-10-01

    There are significant issues regarding Large Scale System integration that are not being addressed in other forums such as current research portfolios or vendor user groups. Unfortunately, the issues in the area of large-scale system integration often fall into a netherworld; not research, not facilities, not procurement, not operations, not user services. Taken together, these issues along with the impact of sub-optimal integration technology means the time required to deploy, integrate and stabilize large scale system may consume up to 20 percent of the useful life of such systems. Improving the state of the art for large scale systems integration has potential to increase the scientific productivity of these systems. Sites have significant expertise, but there are no easy ways to leverage this expertise among them . Many issues inhibit the sharing of information, including available time and effort, as well as issues with sharing proprietary information. Vendors also benefit in the long run from the solutions to issues detected during site testing and integration. There is a great deal of enthusiasm for making large scale system integration a full-fledged partner along with the other major thrusts supported by funding agencies in the definition, design, and use of a petascale systems. Integration technology and issues should have a full 'seat at the table' as petascale and exascale initiatives and programs are planned. The workshop attendees identified a wide range of issues and suggested paths forward. Pursuing these with funding opportunities and innovation offers the opportunity to dramatically improve the state of large scale system integration.

  15. Energy Department Loan Guarantee Would Support Large-Scale Rooftop Solar

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

    Power for U.S. Military Housing | Department of Energy Loan Guarantee Would Support Large-Scale Rooftop Solar Power for U.S. Military Housing Energy Department Loan Guarantee Would Support Large-Scale Rooftop Solar Power for U.S. Military Housing September 7, 2011 - 2:10pm Addthis Washington D.C. - U.S. Energy Secretary Steven Chu today announced the offer of a conditional commitment for a partial guarantee of a $344 million loan that will support the SolarStrong Project, which is expected

  16. Variability of Load and Net Load in Case of Large Scale Distributed Wind Power

    SciTech Connect (OSTI)

    Holttinen, H.; Kiviluoma, J.; Estanqueiro, A.; Gomez-Lazaro, E.; Rawn, B.; Dobschinski, J.; Meibom, P.; Lannoye, E.; Aigner, T.; Wan, Y. H.; Milligan, M.

    2011-01-01

    Large scale wind power production and its variability is one of the major inputs to wind integration studies. This paper analyses measured data from large scale wind power production. Comparisons of variability are made across several variables: time scale (10-60 minute ramp rates), number of wind farms, and simulated vs. modeled data. Ramp rates for Wind power production, Load (total system load) and Net load (load minus wind power production) demonstrate how wind power increases the net load variability. Wind power will also change the timing of daily ramps.

  17. ARM - PI Product - Large Scale Ice Water Path and 3-D Ice Water Content

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

    ProductsLarge Scale Ice Water Path and 3-D Ice Water Content ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Large Scale Ice Water Path and 3-D Ice Water Content Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM

  18. DOE Awards $126.6 Million for Two More Large-Scale Carbon Sequestration

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

    Projects | Department of Energy 6.6 Million for Two More Large-Scale Carbon Sequestration Projects DOE Awards $126.6 Million for Two More Large-Scale Carbon Sequestration Projects May 6, 2008 - 11:30am Addthis Projects in California and Ohio Join Four Others in Effort to Drastically Reduce Greenhouse Gas Emissions WASHINGTON, DC - The U.S. Department of Energy (DOE) today announced awards of more than $126.6 million to the West Coast Regional Carbon Sequestration Partnership (WESTCARB) and

  19. Large-scale delamination of multi-layers transition metal carbides and carbonitrides “MXenes”

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

    Naguib, Michael; Unocic, Raymond R.; Armstrong, Beth L.; Nanda, Jagjit

    2015-04-17

    Herein we report on a general approach to delaminate multi-layered MXenes using an organic base to induce swelling that in turn weakens the bonds between the MX layers. Simple agitation or mild sonication of the swollen MXene in water resulted in the large-scale delamination of the MXene layers. The delamination method is demonstrated for vanadium carbide, and titanium carbonitrides MXenes.

  20. Large-Scale Delamination of Multi-Layers Transition Metal Carbides and Carbonitrides MXenes

    SciTech Connect (OSTI)

    Abdelmalak, Michael Naguib; Unocic, Raymond R; Armstrong, Beth L; Nanda, Jagjit

    2015-01-01

    Herein we report on a general approach to delaminate multi-layered MXenes using an organic base to induce swelling that in turn weakens the bonds between the MX layers. Simple agitation or mild sonication of the swollen MXene in water resulted in the large-scale delamination of the MXene layers. The delamination method is demonstrated for vanadium carbide, and titanium carbonitrides MXenes.

  1. First U.S. Large-Scale CO2 Storage Project Advances

    Broader source: Energy.gov [DOE]

    Drilling nears completion for the first large-scale carbon dioxide injection well in the United States for CO2 sequestration. This project will be used to demonstrate that CO2 emitted from industrial sources - such as coal-fired power plants - can be stored in deep geologic formations to mitigate large quantities of greenhouse gas emissions.

  2. Self-consistency tests of large-scale dynamics parameterizations for single-column modeling

    SciTech Connect (OSTI)

    Edman, Jacob P.; Romps, David M.

    2015-03-18

    Large-scale dynamics parameterizations are tested numerically in cloud-resolving simulations, including a new version of the weak-pressure-gradient approximation (WPG) introduced by Edman and Romps (2014), the weak-temperature-gradient approximation (WTG), and a prior implementation of WPG. We perform a series of self-consistency tests with each large-scale dynamics parameterization, in which we compare the result of a cloud-resolving simulation coupled to WTG or WPG with an otherwise identical simulation with prescribed large-scale convergence. In self-consistency tests based on radiative-convective equilibrium (RCE; i.e., no large-scale convergence), we find that simulations either weakly coupled or strongly coupled to either WPG or WTG are self-consistent, but WPG-coupled simulations exhibit a nonmonotonic behavior as the strength of the coupling to WPG is varied. We also perform self-consistency tests based on observed forcings from two observational campaigns: the Tropical Warm Pool International Cloud Experiment (TWP-ICE) and the ARM Southern Great Plains (SGP) Summer 1995 IOP. In these tests, we show that the new version of WPG improves upon prior versions of WPG by eliminating a potentially troublesome gravity-wave resonance.

  3. Self-consistency tests of large-scale dynamics parameterizations for single-column modeling

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

    Edman, Jacob P.; Romps, David M.

    2015-03-18

    Large-scale dynamics parameterizations are tested numerically in cloud-resolving simulations, including a new version of the weak-pressure-gradient approximation (WPG) introduced by Edman and Romps (2014), the weak-temperature-gradient approximation (WTG), and a prior implementation of WPG. We perform a series of self-consistency tests with each large-scale dynamics parameterization, in which we compare the result of a cloud-resolving simulation coupled to WTG or WPG with an otherwise identical simulation with prescribed large-scale convergence. In self-consistency tests based on radiative-convective equilibrium (RCE; i.e., no large-scale convergence), we find that simulations either weakly coupled or strongly coupled to either WPG or WTG are self-consistent, butmore » WPG-coupled simulations exhibit a nonmonotonic behavior as the strength of the coupling to WPG is varied. We also perform self-consistency tests based on observed forcings from two observational campaigns: the Tropical Warm Pool International Cloud Experiment (TWP-ICE) and the ARM Southern Great Plains (SGP) Summer 1995 IOP. In these tests, we show that the new version of WPG improves upon prior versions of WPG by eliminating a potentially troublesome gravity-wave resonance.« less

  4. LY? FOREST TOMOGRAPHY FROM BACKGROUND GALAXIES: THE FIRST MEGAPARSEC-RESOLUTION LARGE-SCALE STRUCTURE MAP AT z > 2

    SciTech Connect (OSTI)

    Lee, Khee-Gan; Hennawi, Joseph F.; Eilers, Anna-Christina [Max Planck Institute for Astronomy, Knigstuhl 17, D-69117 Heidelberg (Germany); Stark, Casey; White, Martin [Department of Astronomy, University of California at Berkeley, B-20 Hearst Field Annex 3411, Berkeley, CA 94720 (United States); Prochaska, J. Xavier [Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Schlegel, David J. [University of California Observatories, Lick Observatory, 1156 High Street, Santa Cruz, CA 95064 (United States); Arinyo-i-Prats, Andreu [Institut de Cincies del Cosmos, Universitat de Barcelona (IEEC-UB), Mart Franqus 1, E-08028 Barcelona (Spain); Suzuki, Nao [Kavli Institute for the Physics and Mathematics of the Universe (IPMU), The University of Tokyo, Kashiwano-ha 5-1-5, Kashiwa-shi, Chiba (Japan); Croft, Rupert A. C. [Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Caputi, Karina I. [Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700-AV Groningen (Netherlands); Cassata, Paolo [Instituto de Fisica y Astronomia, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Casilla 5030, Valparaiso (Chile); Ilbert, Olivier; Le Brun, Vincent; Le Fvre, Olivier [Aix Marseille Universit, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, F-13388 Marseille (France); Garilli, Bianca [INAF-IASF, Via Bassini 15, I-20133, Milano (Italy); Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Maccagni, Dario [INAF-Osservatorio Astronomico di Bologna, Via Ranzani,1, I-40127 Bologna (Italy); Nugent, Peter, E-mail: lee@mpia.de [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); and others

    2014-11-01

    We present the first observations of foreground Ly? forest absorption from high-redshift galaxies, targeting 24 star-forming galaxies (SFGs) with z ? 2.3-2.8 within a 5' 14' region of the COSMOS field. The transverse sightline separation is ?2 h {sup 1} Mpc comoving, allowing us to create a tomographic reconstruction of the three-dimensional (3D) Ly? forest absorption field over the redshift range 2.20 ? z ? 2.45. The resulting map covers 6 h {sup 1} Mpc 14 h {sup 1} Mpc in the transverse plane and 230 h {sup 1} Mpc along the line of sight with a spatial resolution of ?3.5 h {sup 1} Mpc, and is the first high-fidelity map of a large-scale structure on ?Mpc scales at z > 2. Our map reveals significant structures with ? 10 h {sup 1} Mpc extent, including several spanning the entire transverse breadth, providing qualitative evidence for the filamentary structures predicted to exist in the high-redshift cosmic web. Simulated reconstructions with the same sightline sampling, spectral resolution, and signal-to-noise ratio recover the salient structures present in the underlying 3D absorption fields. Using data from other surveys, we identified 18 galaxies with known redshifts coeval with our map volume, enabling a direct comparison with our tomographic map. This shows that galaxies preferentially occupy high-density regions, in qualitative agreement with the same comparison applied to simulations. Our results establish the feasibility of the CLAMATO survey, which aims to obtain Ly? forest spectra for ?1000 SFGs over ?1 deg{sup 2} of the COSMOS field, in order to map out the intergalactic medium large-scale structure at (z) ? 2.3 over a large volume (100 h {sup 1} Mpc){sup 3}.

  5. Analysis and experimental study on formation conditions of large-scale barrier-free diffuse atmospheric pressure air plasmas in repetitive pulse mode

    SciTech Connect (OSTI)

    Li, Lee Liu, Lun; Liu, Yun-Long; Bin, Yu; Ge, Ya-Feng; Lin, Fo-Chang

    2014-01-14

    Atmospheric air diffuse plasmas have enormous application potential in various fields of science and technology. Without dielectric barrier, generating large-scale air diffuse plasmas is always a challenging issue. This paper discusses and analyses the formation mechanism of cold homogenous plasma. It is proposed that generating stable diffuse atmospheric plasmas in open air should meet the three conditions: high transient power with low average power, excitation in low average E-field with locally high E-field region, and multiple overlapping electron avalanches. Accordingly, an experimental configuration of generating large-scale barrier-free diffuse air plasmas is designed. Based on runaway electron theory, a low duty-ratio, high voltage repetitive nanosecond pulse generator is chosen as a discharge excitation source. Using the wire-electrodes with small curvature radius, the gaps with highly non-uniform E-field are structured. Experimental results show that the volume-scaleable, barrier-free, homogeneous air non-thermal plasmas have been obtained between the gap spacing with the copper-wire electrodes. The area of air cold plasmas has been up to hundreds of square centimeters. The proposed formation conditions of large-scale barrier-free diffuse air plasmas are proved to be reasonable and feasible.

  6. The absorption chiller in large scale solar pond cooling design with condenser heat rejection in the upper convecting zone

    SciTech Connect (OSTI)

    Tsilingiris, P.T. )

    1992-07-01

    The possibility of using solar ponds as low-cost solar collectors combined with commercial absorption chillers in large scale solar cooling design is investigated. The analysis is based on the combination of a steady-state solar pond mathematical model with the operational characteristics of a commercial absorption chiller, assuming condenser heat rejection in the upper convecting zone (U.C.Z.). The numerical solution of the nonlinear equations involved leads to results which relate the chiller capacity with pond design and environmental parameters, which are also employed for the investigation of the optimum pond size for a minimum capital cost. The derived cost per cooling kW for a 350 kW chiller ranges from about 300 to 500 $/kW cooling. This is almost an order of magnitude lower than using a solar collector field of evacuated tube type.

  7. A PRACTICAL ONTOLOGY FOR THE LARGE-SCALE MODELING OF SCHOLARLY ARTIFACTS AND THEIR USAGE

    SciTech Connect (OSTI)

    RODRIGUEZ, MARKO A.; BOLLEN, JOHAN; VAN DE SOMPEL, HERBERT

    2007-01-30

    The large-scale analysis of scholarly artifact usage is constrained primarily by current practices in usage data archiving, privacy issues concerned with the dissemination of usage data, and the lack of a practical ontology for modeling the usage domain. As a remedy to the third constraint, this article presents a scholarly ontology that was engineered to represent those classes for which large-scale bibliographic and usage data exists, supports usage research, and whose instantiation is scalable to the order of 50 million articles along with their associated artifacts (e.g. authors and journals) and an accompanying 1 billion usage events. The real world instantiation of the presented abstract ontology is a semantic network model of the scholarly community which lends the scholarly process to statistical analysis and computational support. They present the ontology, discuss its instantiation, and provide some example inference rules for calculating various scholarly artifact metrics.

  8. Simultaneous effect of modified gravity and primordial non-Gaussianity in large scale structure observations

    SciTech Connect (OSTI)

    Mirzatuny, Nareg; Khosravi, Shahram; Baghram, Shant; Moshafi, Hossein E-mail: khosravi@mail.ipm.ir E-mail: hosseinmoshafi@iasbs.ac.ir

    2014-01-01

    In this work we study the simultaneous effect of primordial non-Gaussianity and the modification of the gravity in f(R) framework on large scale structure observations. We show that non-Gaussianity and modified gravity introduce a scale dependent bias and growth rate functions. The deviation from ΛCDM in the case of primordial non-Gaussian models is in large scales, while the growth rate deviates from ΛCDM in small scales for modified gravity theories. We show that the redshift space distortion can be used to distinguish positive and negative f{sub NL} in standard background, while in f(R) theories they are not easily distinguishable. The galaxy power spectrum is generally enhanced in presence of non-Gaussianity and modified gravity. We also obtain the scale dependence of this enhancement. Finally we define galaxy growth rate and galaxy growth rate bias as new observational parameters to constrain cosmology.

  9. Optimization of large-scale heterogeneous system-of-systems models.

    SciTech Connect (OSTI)

    Parekh, Ojas; Watson, Jean-Paul; Phillips, Cynthia Ann; Siirola, John; Swiler, Laura Painton; Hough, Patricia Diane; Lee, Herbert K. H.; Hart, William Eugene; Gray, Genetha Anne; Woodruff, David L.

    2012-01-01

    Decision makers increasingly rely on large-scale computational models to simulate and analyze complex man-made systems. For example, computational models of national infrastructures are being used to inform government policy, assess economic and national security risks, evaluate infrastructure interdependencies, and plan for the growth and evolution of infrastructure capabilities. A major challenge for decision makers is the analysis of national-scale models that are composed of interacting systems: effective integration of system models is difficult, there are many parameters to analyze in these systems, and fundamental modeling uncertainties complicate analysis. This project is developing optimization methods to effectively represent and analyze large-scale heterogeneous system of systems (HSoS) models, which have emerged as a promising approach for describing such complex man-made systems. These optimization methods enable decision makers to predict future system behavior, manage system risk, assess tradeoffs between system criteria, and identify critical modeling uncertainties.

  10. Panel 1, Towards Sustainable Energy Systems: The Role of Large-Scale Hydrogen Storage in Germany

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

    Hanno Butsch | Head of International Cooperation NOW GmbH National Organization Hydrogen and Fuel Cell Technology Towards sustainable energy systems - The role of large scale hydrogen storage in Germany May 14th, 2014 | Sacramento Political background for the transition to renewable energies 2 * Climate protection: Global responsibility for the next generation. * Energy security: More independency from fossil fuels. * Securing the economy: Creating new markets and jobs through innovations. Three

  11. Final Report: Large-Scale Optimization for Bayesian Inference in Complex Systems

    SciTech Connect (OSTI)

    Ghattas, Omar

    2013-10-15

    The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimiza- tion) Project focuses on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimiza- tion and inversion methods. Our research is directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. Our efforts are integrated in the context of a challenging testbed problem that considers subsurface reacting flow and transport. The MIT component of the SAGUARO Project addresses the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas-Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to- observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as "reduce then sample" and "sample then reduce." In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to achieve their speedups.

  12. Topology-Aware Mappings for Large-Scale Eigenvalue Problems | Argonne

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

    Leadership Computing Facility Topology-Aware Mappings for Large-Scale Eigenvalue Problems Authors: Aktulga, H.M., Yang, C., Ng.,E.G., Maris, P., Vary, J.P. Obtaining highly accurate predictions for properties of light atomic nuclei using the Configuration Interaction (CI) approach requires computing the lowest eigenvalues and associated eigenvectors of a large many-body nuclear Hamiltonian matrix, H ˆ . Since H ˆ is a large sparse matrix, a parallel iterative eigensolver designed for

  13. Metal Catalyzed sp2 Bonded Carbon - Large-scale Graphene Synthesis and

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

    Beyond | MIT-Harvard Center for Excitonics Metal Catalyzed sp2 Bonded Carbon - Large-scale Graphene Synthesis and Beyond December 1, 2009 at 3pm/36-428 Peter Sutter Center for Functional Nanomaterials sutter abstract: Carbon honeycomb lattices have shown a number of remarkable properties. When wrapped up into fullerenes, for instance, superconductivity with high transition temperatures can be induced by alkali intercalation. Rolling carbon sheets up into 1-dimensional nanotubes generates the

  14. Large-Scale Production of Marine Microalgae for Fuel and Feeds

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

    Bioenergy Technologies Office (BETO) 2015 Project Peer Review Large-Scale Production of Marine Microalgae for Fuel and Feeds March 24, 2015 Algae Platform Review Mark Huntley Cornell Marine Algal Biofuels Consortium This presentation does not contain any proprietary, confidential, or otherwise restricted information Goal Statement  BETO MYPP Goals (3) Demonstrate 1. Performance against clear cost goals and technical targets (Q4 2013) 2. Productivity of 1,500 gal/acre/yr algal oil (Q4 2014)

  15. Large-Scale Simulation of Brain Tissue: Blue Brain Project, EPFL | Argonne

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

    Leadership Computing Facility Digital reconstruction of pyramidal cells Digital reconstruction of pyramidal cells. Blue Brain Project, Ecole Polytechnique Federale de Lausanne Large-Scale Simulation of Brain Tissue: Blue Brain Project, EPFL PI Name: Fabien Delalondre PI Email: fabien.delalondre@epfl.ch Institution: Ecole Federale Polytechnique de Lausanne Allocation Program: ESP Year: 2015 Research Domain: Biological Sciences Tier 1 Science Project Science This ESP project will be used to

  16. A method of orbital analysis for large-scale first-principles simulations

    SciTech Connect (OSTI)

    Ohwaki, Tsukuru; Otani, Minoru; Ozaki, Taisuke

    2014-06-28

    An efficient method of calculating the natural bond orbitals (NBOs) based on a truncation of the entire density matrix of a whole system is presented for large-scale density functional theory calculations. The method recovers an orbital picture for O(N) electronic structure methods which directly evaluate the density matrix without using Kohn-Sham orbitals, thus enabling quantitative analysis of chemical reactions in large-scale systems in the language of localized Lewis-type chemical bonds. With the density matrix calculated by either an exact diagonalization or O(N) method, the computational cost is O(1) for the calculation of NBOs associated with a local region where a chemical reaction takes place. As an illustration of the method, we demonstrate how an electronic structure in a local region of interest can be analyzed by NBOs in a large-scale first-principles molecular dynamics simulation for a liquid electrolyte bulk model (propylene carbonate + LiBF{sub 4})

  17. Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

    SciTech Connect (OSTI)

    Bonne, François; Bonnay, Patrick

    2014-01-29

    In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  18. Materials Science and Materials Chemistry for Large Scale Electrochemical Energy Storage: From Transportation to Electrical Grid

    SciTech Connect (OSTI)

    Liu, Jun; Zhang, Jiguang; Yang, Zhenguo; Lemmon, John P.; Imhoff, Carl H.; Graff, Gordon L.; Li, Liyu; Hu, Jian Z.; Wang, Chong M.; Xiao, Jie; Xia, Guanguang; Viswanathan, Vilayanur V.; Baskaran, Suresh; Sprenkle, Vincent L.; Li, Xiaolin; Shao, Yuyan; Schwenzer, Birgit

    2013-02-15

    Large-scale electrical energy storage has become more important than ever for reducing fossil energy consumption in transportation and for the widespread deployment of intermittent renewable energy in electric grid. However, significant challenges exist for its applications. Here, the status and challenges are reviewed from the perspective of materials science and materials chemistry in electrochemical energy storage technologies, such as Li-ion batteries, sodium (sulfur and metal halide) batteries, Pb-acid battery, redox flow batteries, and supercapacitors. Perspectives and approaches are introduced for emerging battery designs and new chemistry combinations to reduce the cost of energy storage devices.

  19. Networks of silicon nanowires: A large-scale atomistic electronic structure analysis

    SciTech Connect (OSTI)

    Kele?, mit; Bulutay, Ceyhun; Liedke, Bartosz; Heinig, Karl-Heinz

    2013-11-11

    Networks of silicon nanowires possess intriguing electronic properties surpassing the predictions based on quantum confinement of individual nanowires. Employing large-scale atomistic pseudopotential computations, as yet unexplored branched nanostructures are investigated in the subsystem level as well as in full assembly. The end product is a simple but versatile expression for the bandgap and band edge alignments of multiply-crossing Si nanowires for various diameters, number of crossings, and wire orientations. Further progress along this line can potentially topple the bottom-up approach for Si nanowire networks to a top-down design by starting with functionality and leading to an enabling structure.

  20. NREL Offers an Open-Source Solution for Large-Scale Energy Data Collection

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

    and Analysis - News Releases | NREL NREL Offers an Open-Source Solution for Large-Scale Energy Data Collection and Analysis June 18, 2013 The Energy Department's National Renewable Energy Laboratory (NREL) is launching an open-source system for storing, integrating, and aligning energy-related time-series data. NREL's Energy DataBus is used for tracking and analyzing energy use on its own campus. The system is applicable to other facilities-including anything from a single building to a

  1. Testing the big bang: Light elements, neutrinos, dark matter and large-scale structure

    SciTech Connect (OSTI)

    Schramm, D.N. Fermi National Accelerator Lab., Batavia, IL )

    1991-06-01

    In this series of lectures, several experimental and observational tests of the standard cosmological model are examined. In particular, detailed discussion is presented regarding nucleosynthesis, the light element abundances and neutrino counting; the dark matter problems; and the formation of galaxies and large-scale structure. Comments will also be made on the possible implications of the recent solar neutrino experimental results for cosmology. An appendix briefly discusses the 17 keV thing'' and the cosmological and astrophysical constraints on it. 126 refs., 8 figs., 2 tabs.

  2. Technical and economical aspects of large-scale CO{sub 2} storage in deep oceans

    SciTech Connect (OSTI)

    Sarv, H.; John, J.

    2000-07-01

    The authors examined the technical and economical feasibility of two options for large-scale transportation and ocean sequestration of captured CO{sub 2} at depths of 3000 meters or greater. In one case, CO{sub 2} was pumped from a land-based collection center through six parallel-laid subsea pipelines. Another case considered oceanic tanker transport of liquid carbon dioxide to an offshore floating platform or a barge for vertical injection through a large-diameter pipe to the ocean floor. Based on the preliminary technical and economic analyses, tanker transportation and offshore injection through a large-diameter, 3,000-meter vertical pipeline from a floating structure appears to be the best method for delivering liquid CO{sub 2} to deep ocean floor depressions for distances greater than 400 km. Other benefits of offshore injection are high payload capability and ease of relocation. For shorter distances (less than 400 km), CO{sub 2} delivery by subsea pipelines is more cost-effective. Estimated costs for 500-km transport and storage at a depth of 3000 meters by subsea pipelines or tankers were under 2 dollars per ton of stored CO{sub 2}. Their analyses also indicates that large-scale sequestration of captured CO{sub 2} in oceans is technologically feasible and has many commonalities with other strategies for deepsea natural gas and oil exploration installations.

  3. Large-scale structure in brane-induced gravity. I. Perturbation theory

    SciTech Connect (OSTI)

    Scoccimarro, Roman

    2009-11-15

    We study the growth of subhorizon perturbations in brane-induced gravity using perturbation theory. We solve for the linear evolution of perturbations taking advantage of the symmetry under gauge transformations along the extra-dimension to decouple the bulk equations in the quasistatic approximation, which we argue may be a better approximation at large scales than thought before. We then study the nonlinearities in the bulk and brane equations, concentrating on the workings of the Vainshtein mechanism by which the theory becomes general relativity (GR) at small scales. We show that at the level of the power spectrum, to a good approximation, the effect of nonlinearities in the modified gravity sector may be absorbed into a renormalization of the gravitational constant. Since the relation between the lensing potential and density perturbations is entirely unaffected by the extra physics in these theories, the modified gravity can be described in this approximation by a single function, an effective gravitational constant for nonrelativistic motion that depends on space and time. We develop a resummation scheme to calculate it, and provide predictions for the nonlinear power spectrum. At the level of the large-scale bispectrum, the leading order corrections are obtained by standard perturbation theory techniques, and show that the suppression of the brane-bending mode leads to characteristic signatures in the non-Gaussianity generated by gravity, generic to models that become GR at small scales through second-derivative interactions. We compare the predictions in this work to numerical simulations in a companion paper.

  4. Large Scale Ice Water Path and 3-D Ice Water Content

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

    Liu, Guosheng

    2008-01-15

    Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the radar/lidar/radiometer observations at the ARM site are single-point measurement, therefore, do not provide horizontal distribution of condensed water. The intention of this product is to provide large-scale distribution of cloud ice water by merging available surface and satellite measurements. The satellite cloud ice water algorithm uses ARM ground-based measurements as baseline, produces datasets for 3-D cloud ice water distributions in a 10 deg x 10 deg area near ARM site. The approach of the study is to expand a (surface) point measurement to an (satellite) areal measurement. That is, this study takes the advantage of the high quality cloud measurements at the point of ARM site. We use the cloud characteristics derived from the point measurement to guide/constrain satellite retrieval, then use the satellite algorithm to derive the cloud ice water distributions within an area, i.e., 10 deg x 10 deg centered at ARM site.

  5. Environmental performance evaluation of large-scale municipal solid waste incinerators using data envelopment analysis

    SciTech Connect (OSTI)

    Chen, H.-W.; Chang, N.-B.; Chen, J.-C.; Tsai, S.-J.

    2010-07-15

    Limited to insufficient land resources, incinerators are considered in many countries such as Japan and Germany as the major technology for a waste management scheme capable of dealing with the increasing demand for municipal and industrial solid waste treatment in urban regions. The evaluation of these municipal incinerators in terms of secondary pollution potential, cost-effectiveness, and operational efficiency has become a new focus in the highly interdisciplinary area of production economics, systems analysis, and waste management. This paper aims to demonstrate the application of data envelopment analysis (DEA) - a production economics tool - to evaluate performance-based efficiencies of 19 large-scale municipal incinerators in Taiwan with different operational conditions. A 4-year operational data set from 2002 to 2005 was collected in support of DEA modeling using Monte Carlo simulation to outline the possibility distributions of operational efficiency of these incinerators. Uncertainty analysis using the Monte Carlo simulation provides a balance between simplifications of our analysis and the soundness of capturing the essential random features that complicate solid waste management systems. To cope with future challenges, efforts in the DEA modeling, systems analysis, and prediction of the performance of large-scale municipal solid waste incinerators under normal operation and special conditions were directed toward generating a compromised assessment procedure. Our research findings will eventually lead to the identification of the optimal management strategies for promoting the quality of solid waste incineration, not only in Taiwan, but also elsewhere in the world.

  6. Large Scale Ice Water Path and 3-D Ice Water Content

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

    Liu, Guosheng

    Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the radar/lidar/radiometer observations at the ARM site are single-point measurement, therefore, do not provide horizontal distribution of condensed water. The intention of this product is to provide large-scale distribution of cloud ice water by merging available surface and satellite measurements. The satellite cloud ice water algorithm uses ARM ground-based measurements as baseline, produces datasets for 3-D cloud ice water distributions in a 10 deg x 10 deg area near ARM site. The approach of the study is to expand a (surface) point measurement to an (satellite) areal measurement. That is, this study takes the advantage of the high quality cloud measurements at the point of ARM site. We use the cloud characteristics derived from the point measurement to guide/constrain satellite retrieval, then use the satellite algorithm to derive the cloud ice water distributions within an area, i.e., 10 deg x 10 deg centered at ARM site.

  7. A High-Performance Rechargeable Iron Electrode for Large-Scale Battery-Based Energy Storage

    SciTech Connect (OSTI)

    Manohar, AK; Malkhandi, S; Yang, B; Yang, C; Prakash, GKS; Narayanan, SR

    2012-01-01

    Inexpensive, robust and efficient large-scale electrical energy storage systems are vital to the utilization of electricity generated from solar and wind resources. In this regard, the low cost, robustness, and eco-friendliness of aqueous iron-based rechargeable batteries are particularly attractive and compelling. However, wasteful evolution of hydrogen during charging and the inability to discharge at high rates have limited the deployment of iron-based aqueous batteries. We report here new chemical formulations of the rechargeable iron battery electrode to achieve a ten-fold reduction in the hydrogen evolution rate, an unprecedented charging efficiency of 96%, a high specific capacity of 0.3 Ah/g, and a twenty-fold increase in discharge rate capability. We show that modifying high-purity carbonyl iron by in situ electro-deposition of bismuth leads to substantial inhibition of the kinetics of the hydrogen evolution reaction. The in situ formation of conductive iron sulfides mitigates the passivation by iron hydroxide thereby allowing high discharge rates and high specific capacity to be simultaneously achieved. These major performance improvements are crucial to advancing the prospect of a sustainable large-scale energy storage solution based on aqueous iron-based rechargeable batteries. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.034208jes] All rights reserved.

  8. Nonlinear Seismic Correlation Analysis of the JNES/NUPEC Large-Scale Piping System Tests.

    SciTech Connect (OSTI)

    Nie,J.; DeGrassi, G.; Hofmayer, C.; Ali, S.

    2008-06-01

    The Japan Nuclear Energy Safety Organization/Nuclear Power Engineering Corporation (JNES/NUPEC) large-scale piping test program has provided valuable new test data on high level seismic elasto-plastic behavior and failure modes for typical nuclear power plant piping systems. The component and piping system tests demonstrated the strain ratcheting behavior that is expected to occur when a pressurized pipe is subjected to cyclic seismic loading. Under a collaboration agreement between the US and Japan on seismic issues, the US Nuclear Regulatory Commission (NRC)/Brookhaven National Laboratory (BNL) performed a correlation analysis of the large-scale piping system tests using derailed state-of-the-art nonlinear finite element models. Techniques are introduced to develop material models that can closely match the test data. The shaking table motions are examined. The analytical results are assessed in terms of the overall system responses and the strain ratcheting behavior at an elbow. The paper concludes with the insights about the accuracy of the analytical methods for use in performance assessments of highly nonlinear piping systems under large seismic motions.

  9. Large-scale structure evolution in axisymmetric, compressible free-shear layers

    SciTech Connect (OSTI)

    Aeschliman, D.P.; Baty, R.S.

    1997-05-01

    This paper is a description of work-in-progress. It describes Sandia`s program to study the basic fluid mechanics of large-scale mixing in unbounded, compressible, turbulent flows, specifically, the turbulent mixing of an axisymmetric compressible helium jet in a parallel, coflowing compressible air freestream. Both jet and freestream velocities are variable over a broad range, providing a wide range mixing layer Reynolds number. Although the convective Mach number, M{sub c}, range is currently limited by the present nozzle design to values of 0.6 and below, straightforward nozzle design changes would permit a wide range of convective Mach number, to well in excess of 1.0. The use of helium allows simulation of a hot jet due to the large density difference, and also aids in obtaining optical flow visualization via schlieren due to the large density gradient in the mixing layer. The work comprises a blend of analysis, experiment, and direct numerical simulation (DNS). There the authors discuss only the analytical and experimental efforts to observe and describe the evolution of the large-scale structures. The DNS work, used to compute local two-point velocity correlation data, will be discussed elsewhere.

  10. FERMI RULES OUT THE INVERSE COMPTON/CMB MODEL FOR THE LARGE-SCALE JET X-RAY EMISSION OF 3C 273

    SciTech Connect (OSTI)

    Meyer, Eileen T.; Georganopoulos, Markos

    2014-01-10

    The X-ray emission mechanism in large-scale jets of powerful radio quasars has been a source of debate in recent years, with two competing interpretations: either the X-rays are of synchrotron origin, arising from a different electron energy distribution than that producing the radio to optical synchrotron component, or they are due to inverse Compton scattering of cosmic microwave background photons (IC/CMB) by relativistic electrons in a powerful relativistic jet with bulk Lorentz factor ? ? 10-20. These two models imply radically different conditions in the large-scale jet in terms of jet speed, kinetic power, and maximum energy of the particle acceleration mechanism, with important implications for the impact of the jet on the large-scale environment. A large part of the X-ray origin debate has centered on the well-studied source 3C 273. Here we present new observations from Fermi which put an upper limit on the gamma-ray flux from the large-scale jet of 3C 273 that violates at a confidence greater that 99.9% the flux expected from the IC/CMB X-ray model found by extrapolation of the UV to X-ray spectrum of knot A, thus ruling out the IC/CMB interpretation entirely for this source when combined with previous work. Further, this upper limit from Fermi puts a limit on the Doppler beaming factor of at least ? <9, assuming equipartition fields, and possibly as low as ? <5, assuming no major deceleration of the jet from knots A throughD1.