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Note: This page contains sample records for the topic "massively parallel microcell-based" from the National Library of EnergyBeta (NLEBeta).
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1

Unsteady Turbomachinery Computations Using Massively Parallel Platforms  

E-Print Network (OSTI)

Unsteady Turbomachinery Computations Using Massively Parallel Platforms Edwin van der Weide with the inherently unsteady nature of turbomachinery flows, due to the motion of the rotors, this means

Alonso, Juan J.

2

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND  

E-Print Network (OSTI)

VALIDATION OF MASSIVELY PARALLEL SIMULATIONS OF DYNAMIC FRACTURE AND FRAGMENTATION OF BRITTLE element simulations of dynamic fracture and fragmentation of brittle solids are presented. Fracture the results of massively parallel numerical simulations of dynamic fracture and fragmentation in brittle

Barr, Al

3

Massively Parallel Indirect Dielectrophoresis Controlled Placement of Carbon Nanotubes.  

E-Print Network (OSTI)

??Placement of single walled carbon nanotubes is demonstrated through massively parallel indirect dielectrophoresis (MPID). MPID is shown to be able to control the placement of… (more)

Conley, Hiram Jacob

2009-01-01T23:59:59.000Z

4

Routing performance analysis and optimization within a massively parallel computer  

DOE Patents (OSTI)

An apparatus, program product and method optimize the operation of a massively parallel computer system by, in part, receiving actual performance data concerning an application executed by the plurality of interconnected nodes, and analyzing the actual performance data to identify an actual performance pattern. A desired performance pattern may be determined for the application, and an algorithm may be selected from among a plurality of algorithms stored within a memory, the algorithm being configured to achieve the desired performance pattern based on the actual performance data.

Archer, Charles Jens; Peters, Amanda; Pinnow, Kurt Walter; Swartz, Brent Allen

2013-04-16T23:59:59.000Z

5

Pseudorandom number generator for massively parallel molecular-dynamics simulations  

Science Journals Connector (OSTI)

A class of uniform pseudorandom number generators is proposed for modeling and simulations on massively parallel computers. The algorithm is simple, nonrecursive, and is easily transported to serial or vector computers. We have tested the procedure for uniformity, independence, and correlations by several methods. Related, less complex sequences passed some of these tests well enough; however, inadequacies were revealed by tests for correlations and in an interesting application, namely, annealing from an initial lattice that is mechanically unstable. In the latter case, initial velocities chosen by a random number generator that is not sufficiently random lead quickly to unphysical regularity in grain structure. The new class of generators passes this dynamical diagnostic for unwanted correlations.

Brad Lee Holian; Ora E. Percus; Tony T. Warnock; Paula A. Whitlock

1994-08-01T23:59:59.000Z

6

The Evolution of the Massively Parallel Processing Database in Support of Visual Analytics  

Science Journals Connector (OSTI)

This article explores the evolution of the Massively Parallel Processing MPP database, focusing on trends of particular relevance to analytics. The dramatic shift of database vendors and leading companies to utilize MPP databases and deploy an Enterprise ... Keywords: Decision Support Workload, Enterprise Analytics, Enterprise Data Warehouse EDW, Massively Parallel Processing MPP Database, Visual Analytics

Ian A. Willson

2011-10-01T23:59:59.000Z

7

Massively parallel processor networks with optical express channels  

DOE Patents (OSTI)

An optical method for separating and routing local and express channel data comprises interconnecting the nodes in a network with fiber optic cables. A single fiber optic cable carries both express channel traffic and local channel traffic, e.g., in a massively parallel processor (MPP) network. Express channel traffic is placed on, or filtered from, the fiber optic cable at a light frequency or a color different from that of the local channel traffic. The express channel traffic is thus placed on a light carrier that skips over the local intermediate nodes one-by-one by reflecting off of selective mirrors placed at each local node. The local-channel-traffic light carriers pass through the selective mirrors and are not reflected. A single fiber optic cable can thus be threaded throughout a three-dimensional matrix of nodes with the x,y,z directions of propagation encoded by the color of the respective light carriers for both local and express channel traffic. Thus frequency division multiple access is used to hierarchically separate the local and express channels to eliminate the bucket brigade latencies that would otherwise result if the express traffic had to hop between every local node to reach its ultimate destination.

Deri, Robert J. (Pleasanton, CA); Brooks, III, Eugene D. (Livermore, CA); Haigh, Ronald E. (Tracy, CA); DeGroot, Anthony J. (Castro Valley, CA)

1999-01-01T23:59:59.000Z

8

Massively parallel computational fluid dynamics calculations for aerodynamics and aerothermodynamics applications  

SciTech Connect

Massively parallel computers have enabled the analyst to solve complicated flow fields (turbulent, chemically reacting) that were previously intractable. Calculations are presented using a massively parallel CFD code called SACCARA (Sandia Advanced Code for Compressible Aerothermodynamics Research and Analysis) currently under development at Sandia National Laboratories as part of the Department of Energy (DOE) Accelerated Strategic Computing Initiative (ASCI). Computations were made on a generic reentry vehicle in a hypersonic flowfield utilizing three different distributed parallel computers to assess the parallel efficiency of the code with increasing numbers of processors. The parallel efficiencies for the SACCARA code will be presented for cases using 1, 150, 100 and 500 processors. Computations were also made on a subsonic/transonic vehicle using both 236 and 521 processors on a grid containing approximately 14.7 million grid points. Ongoing and future plans to implement a parallel overset grid capability and couple SACCARA with other mechanics codes in a massively parallel environment are discussed.

Payne, J.L.; Hassan, B.

1998-09-01T23:59:59.000Z

9

Massively parallel DNA sequencing: the new frontier in biogeography  

E-Print Network (OSTI)

2007) Popula? tion  genomics:  whole?genome  analysis  of evolutionary scales.  BMC  Genomics, 13, 403.   Bickford, 2012)  Population  genomics  of  parallel  adaptation  in 

Rocha, Luiz A.; Bernal, Moisés A.; Gaither, Michelle R.; Alfaro, Michael E.

2013-01-01T23:59:59.000Z

10

Performance evaluations of gyrokinetic Eulerian code GT5D on massively parallel multi-core platforms  

Science Journals Connector (OSTI)

A gyrokinetic toroidal five dimensional Eulerian code GT5D [Y.Idomura et. al., Comput. Phys. Commun 179, 391 (2008)] is ported on five advanced massively parallel platforms and comprehensive benchmark tests are performed. Sustained performances ... Keywords: Eulerian code, GT5D, fusion plasma turbulence, gyrokinetic simulation, hybrid parallel model, sustained performance

Yasuhiro Idomura; Sébastien Jolliet

2011-11-01T23:59:59.000Z

11

Massive Data-Parallel Swarm Simulation and Visualisation using CUDA  

E-Print Network (OSTI)

for the project was to employ CUDA for simulating natural movement and behaviour of a fish swarm. As a fish swarm by calculating the state of a fish at time ti+1 as a function of the state of the whole swarm at time ti. Since this function is equal for all fishes, the state of the whole swarm can easily be calculated in parallel

Hinze, Thomas

12

Massively parallel X-ray holography STEFANO MARCHESINI1,2  

E-Print Network (OSTI)

, and a bacterial cell with a soft-X-ray free-electron laser, where illumination by a single 15-fs pulse was successfully used in producing the holographic image. As X-ray lasers move to shorter wavelengths we expectMassively parallel X-ray holography STEFANO MARCHESINI1,2 *, SE´BASTIEN BOUTET3,4 , ANNE E

Petta, Jason

13

Self-Assembly Techniques for Massively Parallel Packaging of MEMS Devices  

E-Print Network (OSTI)

Self-Assembly Techniques for Massively Parallel Packaging of MEMS Devices Jiandong Fang-1346, or to the author. Signature Date July 31, 2006 #12;#12;University of Washington Abstract Self-Assembly Techniques. B¨ohringer Electrical Engineering This dissertation investigates applications of self-assembly

14

Massively-parallel Spectral Element Algorithm Development for High Speed Flows  

E-Print Network (OSTI)

Fluid Dynamics in the Design Cycle . . . . . . . . . . 3 1.2.1 Nature of the Flow Equations and Turbulence . . . . . . . . . 3 1.2.2 Industrial CFD Use . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2.3 Massive-parallelism and CFD... . . . . . . . . . . . . . . . . . . 7 1.2.4 Towards Improving Design Cycle Analysis . . . . . . . . . . . 7 1.3 Keys for Effective High-Fidelity CFD . . . . . . . . . . . . . . . . . . 9 1.3.1 Need for High Order . . . . . . . . . . . . . . . . . . . . . . . 9 1.3.2 Need for High...

Camp, Joshua Lane

2013-10-07T23:59:59.000Z

15

Massively parallel Monte Carlo for many-particle simulations on GPUs  

SciTech Connect

Current trends in parallel processors call for the design of efficient massively parallel algorithms for scientific computing. Parallel algorithms for Monte Carlo simulations of thermodynamic ensembles of particles have received little attention because of the inherent serial nature of the statistical sampling. In this paper, we present a massively parallel method that obeys detailed balance and implement it for a system of hard disks on the GPU. We reproduce results of serial high-precision Monte Carlo runs to verify the method. This is a good test case because the hard disk equation of state over the range where the liquid transforms into the solid is particularly sensitive to small deviations away from the balance conditions. On a Tesla K20, our GPU implementation executes over one billion trial moves per second, which is 148 times faster than on a single Intel Xeon E5540 CPU core, enables 27 times better performance per dollar, and cuts energy usage by a factor of 13. With this improved performance we are able to calculate the equation of state for systems of up to one million hard disks. These large system sizes are required in order to probe the nature of the melting transition, which has been debated for the last forty years. In this paper we present the details of our computational method, and discuss the thermodynamics of hard disks separately in a companion paper.

Anderson, Joshua A.; Jankowski, Eric [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Grubb, Thomas L. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Engel, Michael [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Glotzer, Sharon C., E-mail: sglotzer@umich.edu [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

2013-12-01T23:59:59.000Z

16

Molecular Dynamics Simulations from SNL's Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS)  

DOE Data Explorer (OSTI)

LAMMPS (http://lammps.sandia.gov/index.html) stands for Large-scale Atomic/Molecular Massively Parallel Simulator and is a code that can be used to model atoms or, as the LAMMPS website says, as a parallel particle simulator at the atomic, meso, or continuum scale. This Sandia-based website provides a long list of animations from large simulations. These were created using different visualization packages to read LAMMPS output, and each one provides the name of the PI and a brief description of the work done or visualization package used. See also the static images produced from simulations at http://lammps.sandia.gov/pictures.html The foundation paper for LAMMPS is: S. Plimpton, Fast Parallel Algorithms for Short-Range Molecular Dynamics, J Comp Phys, 117, 1-19 (1995), but the website also lists other papers describing contributions to LAMMPS over the years.

Plimpton, Steve; Thompson, Aidan; Crozier, Paul

17

Massive parallel generation of indistinguishable single photons via polaritonic superfluid to Mott-insulator quantum phase transition  

E-Print Network (OSTI)

We propose the superfluid to Mott-insulator quantum phase transition in an array of exciton-polariton traps can be utilized for massive parallel generation of indistinguishable single photons. By means of analytical and numerical methods, the device operations and system properties are studied using realistic experimental parameters. Such a deterministic, fault-tolerant, massive parallel generation may open up a new perspective in photonic quantum information processing.

Neil Na; Yoshihisa Yamamoto

2008-04-11T23:59:59.000Z

18

dHybrid: a massively parallel code for hybrid simulations of space plasmas  

E-Print Network (OSTI)

A massively parallel simulation code, called \\textit{dHybrid}, has been developed to perform global scale studies of space plasma interactions. This code is based on an explicit hybrid model; the numerical stability and parallel scalability of the code are studied. A stabilization method for the explicit algorithm, for regions of near zero density, is proposed. Three-dimensional hybrid simulations of the interaction of the solar wind with unmagnetized artificial objects are presented, with a focus on the expansion of a plasma cloud into the solar wind, which creates a diamagnetic cavity and drives the Interplanetary Magnetic Field out of the expansion region. The dynamics of this system can provide insights into other similar scenarios, such as the interaction of the solar wind with unmagnetized planets.

Gargat'e, L; Fonseca, R A; Silva, L O

2006-01-01T23:59:59.000Z

19

ls1 mardyn: The massively parallel molecular dynamics code for large systems  

E-Print Network (OSTI)

The molecular dynamics simulation code ls1 mardyn is presented. It is a highly scalable code, optimized for massively parallel execution on supercomputing architectures, and currently holds the world record for the largest molecular simulation with over four trillion particles. It enables the application of pair potentials to length and time scales which were previously out of scope for molecular dynamics simulation. With an efficient dynamic load balancing scheme, it delivers high scalability even for challenging heterogeneous configurations. Presently, multi-center rigid potential models based on Lennard-Jones sites, point charges and higher-order polarities are supported. Due to its modular design, ls1 mardyn can be extended to new physical models, methods, and algorithms, allowing future users to tailor it to suit their respective needs. Possible applications include scenarios with complex geometries, e.g. for fluids at interfaces, as well as non-equilibrium molecular dynamics simulation of heat and mass transfer.

Christoph Niethammer; Stefan Becker; Martin Bernreuther; Martin Buchholz; Wolfgang Eckhardt; Alexander Heinecke; Stephan Werth; Hans-Joachim Bungartz; Colin W. Glass; Hans Hasse; Jadran Vrabec; Martin Horsch

2014-08-20T23:59:59.000Z

20

3-D readout-electronics packaging for high-bandwidth massively paralleled imager  

DOE Patents (OSTI)

Dense, massively parallel signal processing electronics are co-packaged behind associated sensor pixels. Microchips containing a linear or bilinear arrangement of photo-sensors, together with associated complex electronics, are integrated into a simple 3-D structure (a "mirror cube"). An array of photo-sensitive cells are disposed on a stacked CMOS chip's surface at a 45.degree. angle from light reflecting mirror surfaces formed on a neighboring CMOS chip surface. Image processing electronics are held within the stacked CMOS chip layers. Electrical connections couple each of said stacked CMOS chip layers and a distribution grid, the connections for distributing power and signals to components associated with each stacked CSMO chip layer.

Kwiatkowski, Kris (Los Alamos, NM); Lyke, James (Albuquerque, NM)

2007-12-18T23:59:59.000Z

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


21

Software Project Management and Quality Engineering Practices for Complex, Coupled Multiphysics, Massively Parallel Computational Simulations: Lessons Learned From ASCI  

Science Journals Connector (OSTI)

Many institutions are now developing large-scale, complex, coupled multiphysics computational simulations for massively parallel platforms for the simulation of the performance of nuclear weapons and certification of the stockpile, and for research in ... Keywords: Software engineering, computational science, management, software project, validation, verification

D. E. Post; R. P. Kendall

2004-11-01T23:59:59.000Z

22

An approach for hierarchical system level diagnosis of massively parallel computers combined with a simulation-based method for dependability analysis  

Science Journals Connector (OSTI)

The primary focus in the analysis of massively parallel supercomputers has traditionally been ... topologies, large number of processors, and sophisticated system software can make them very unreliable. If ... of...

J. Altmann; F. Balbach; A. Hein

1994-01-01T23:59:59.000Z

23

Method and apparatus for obtaining stack traceback data for multiple computing nodes of a massively parallel computer system  

DOE Patents (OSTI)

A data collector for a massively parallel computer system obtains call-return stack traceback data for multiple nodes by retrieving partial call-return stack traceback data from each node, grouping the nodes in subsets according to the partial traceback data, and obtaining further call-return stack traceback data from a representative node or nodes of each subset. Preferably, the partial data is a respective instruction address from each node, nodes having identical instruction address being grouped together in the same subset. Preferably, a single node of each subset is chosen and full stack traceback data is retrieved from the call-return stack within the chosen node.

Gooding, Thomas Michael (Rochester, MN); McCarthy, Patrick Joseph (Rochester, MN)

2010-03-02T23:59:59.000Z

24

System and method for representing and manipulating three-dimensional objects on massively parallel architectures  

DOE Patents (OSTI)

A parallel computing system is described that comprises a plurality of uniquely labeled, parallel processors, each processor capable of modelling a three-dimensional object that includes a plurality of vertices, faces and edges. The system comprises a front-end processor for issuing a modelling command to the parallel processors, relating to a three-dimensional object. Each parallel processor, in response to the command and through the use of its own unique label, creates a directed-edge (d-edge) data structure that uniquely relates an edge of the three-dimensional object to one face of the object. Each d-edge data structure at least includes vertex descriptions of the edge and a description of the one face. As a result, each processor, in response to the modelling command, operates upon a small component of the model and generates results, in parallel with all other processors, without the need for processor-to-processor intercommunication.

Karasick, Michael S. (Ridgefield, CT); Strip, David R. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

25

A Novel Algorithm for Solving the Multidimensional Neutron Transport Equation on Massively Parallel Architectures  

SciTech Connect

We employ the Integral Transport Matrix Method (ITMM) as the kernel of new parallel solution methods for the discrete ordinates approximation of the within-group neutron transport equation. The ITMM abandons the repetitive mesh sweeps of the traditional source iterations (SI) scheme in favor of constructing stored operators that account for the direct coupling factors among all the cells' fluxes and between the cells' and boundary surfaces' fluxes. The main goals of this work are to develop the algorithms that construct these operators and employ them in the solution process, determine the most suitable way to parallelize the entire procedure, and evaluate the behavior and parallel performance of the developed methods with increasing number of processes, P. The fastest observed parallel solution method, Parallel Gauss-Seidel (PGS), was used in a weak scaling comparison with the PARTISN transport code, which uses the source iteration (SI) scheme parallelized with the Koch-baker-Alcouffe (KBA) method. Compared to the state-of-the-art SI-KBA with diffusion synthetic acceleration (DSA), this new method- even without acceleration/preconditioning-is completitive for optically thick problems as P is increased to the tens of thousands range. For the most optically thick cells tested, PGS reduced execution time by an approximate factor of three for problems with more than 130 million computational cells on P = 32,768. Moreover, the SI-DSA execution times's trend rises generally more steeply with increasing P than the PGS trend. Furthermore, the PGS method outperforms SI for the periodic heterogeneous layers (PHL) configuration problems. The PGS method outperforms SI and SI-DSA on as few as P = 16 for PHL problems and reduces execution time by a factor of ten or more for all problems considered with more than 2 million computational cells on P = 4.096.

Azmy, Yousry

2014-06-10T23:59:59.000Z

26

Massively parallel linear stability analysis with P ARPACK for 3D uid ow modeled with  

E-Print Network (OSTI)

of the overlaps of the nite element basis functions, N is an up-winded mass matrix, L is the sum parallel simulation code MPSalsa. MPSalsa allows simulation of complex 3D uid ow, heat transfer, and mass is the uid velocity and possible temperature, p is the pressure, M is the symmetric positive de nite matrix

27

Analysis and selection of optimal function implementations in massively parallel computer  

DOE Patents (OSTI)

An apparatus, program product and method optimize the operation of a parallel computer system by, in part, collecting performance data for a set of implementations of a function capable of being executed on the parallel computer system based upon the execution of the set of implementations under varying input parameters in a plurality of input dimensions. The collected performance data may be used to generate selection program code that is configured to call selected implementations of the function in response to a call to the function under varying input parameters. The collected performance data may be used to perform more detailed analysis to ascertain the comparative performance of the set of implementations of the function under the varying input parameters.

Archer, Charles Jens (Rochester, MN); Peters, Amanda (Rochester, MN); Ratterman, Joseph D. (Rochester, MN)

2011-05-31T23:59:59.000Z

28

Method and apparatus for routing data in an inter-nodal communications lattice of a massively parallel computer system by dynamic global mapping of contended links  

SciTech Connect

A massively parallel nodal computer system periodically collects and broadcasts usage data for an internal communications network. A node sending data over the network makes a global routing determination using the network usage data. Preferably, network usage data comprises an N-bit usage value for each output buffer associated with a network link. An optimum routing is determined by summing the N-bit values associated with each link through which a data packet must pass, and comparing the sums associated with different possible routes.

Archer, Charles Jens (Rochester, MN); Musselman, Roy Glenn (Rochester, MN); Peters, Amanda (Rochester, MN); Pinnow, Kurt Walter (Rochester, MN); Swartz, Brent Allen (Chippewa Falls, WI); Wallenfelt, Brian Paul (Eden Prairie, MN)

2011-10-04T23:59:59.000Z

29

Method and apparatus for analyzing error conditions in a massively parallel computer system by identifying anomalous nodes within a communicator set  

DOE Patents (OSTI)

An analytical mechanism for a massively parallel computer system automatically analyzes data retrieved from the system, and identifies nodes which exhibit anomalous behavior in comparison to their immediate neighbors. Preferably, anomalous behavior is determined by comparing call-return stack tracebacks for each node, grouping like nodes together, and identifying neighboring nodes which do not themselves belong to the group. A node, not itself in the group, having a large number of neighbors in the group, is a likely locality of error. The analyzer preferably presents this information to the user by sorting the neighbors according to number of adjoining members of the group.

Gooding, Thomas Michael (Rochester, MN)

2011-04-19T23:59:59.000Z

30

Massively Parallel Part I. Preliminaries  

E-Print Network (OSTI)

program in that chapter mined (computed the golden nonce for) just one Bitcoin. But suppose I want to mine many Bitcoins, K of them. All I have to do is execute K processes, each process running one thread on one core of the cluster, each process run ning the sequential Bitcoin mining program on a different

Kaminsky, Alan

31

Parallel Index  

NLE Websites -- All DOE Office Websites (Extended Search)

Parallel Parallel Index and Query for Large Scale Data Analysis Jerry Chou Kesheng Wu Oliver Rübel Mark Howison Ji Qiang Prabhat Brian Austin E. Wes Bethel Rob D. Ryne Arie Shoshani ABSTRACT Modern scientific datasets present numerous data manage- ment and analysis challenges. State-of-the-art index and query technologies are critical for facilitating interactive ex- ploration of large datasets, but numerous challenges remain in terms of designing a system for processing general scien- tific datasets. The system needs to be able to run on dis- tributed 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 massive datasets on modern supercomputing

32

Massively parallel sequencing of the mouse exome to accurately identify rare, induced mutations: an immediate source for thousands of new mouse models  

Science Journals Connector (OSTI)

...T A/A A/A yes 3 Olfr1253 MK 0.988 3 19910826 het C/C...T A/A A/T yes 3 Osgin2 MK 0.045 4 140271822 het A/A...Solution hybrid selection with ultra-long oligonucleotides for massively...10)77015-4 ) 12 Boles, MK , 2009 Discovery of candidate...

2012-01-01T23:59:59.000Z

33

Characterization of hydrogen dissociation over aluminium-doped zinc oxide using an efficient massively parallel framework for QM/MM calculations  

Science Journals Connector (OSTI)

...evaluations, the new methods result in a two-level...dissociation of a hydrogen molecule over a...physisorbed atomic hydrogen. parallelization...catalysis|zinc oxide|hydrogen dissociation| 1...electronics, energy production, conversion and...user. The QM/MM method (Warshel Levitt...

2011-01-01T23:59:59.000Z

34

Parallel Picoliter RT-PCR Assays Using Microfluidics  

Science Journals Connector (OSTI)

Parallel Picoliter RT-PCR Assays Using Microfluidics ... Massively Parallel Single-Molecule and Single-Cell Emulsion Reverse Transcription Polymerase Chain Reaction Using Agarose Droplet Microfluidics ... Massively Parallel Single-Molecule and Single-Cell Emulsion Reverse Transcription Polymerase Chain Reaction Using Agarose Droplet Microfluidics ...

Joshua S. Marcus; W. French Anderson; Stephen R. Quake

2006-01-04T23:59:59.000Z

35

Massively Parallel Computation of Discrete Logarithms \\Lambda  

E-Print Network (OSTI)

an order of magnitude using such an analysis. Among the reasons for this are: ffl if a high­level language, keeping in mind that log g a is only determined modulo the multiplicative order of g. For general be extremely useful to chart the increase in difficulty of computing discrete logarithms as the field size

McCurley, Kevin

36

Massively Parallel Computation of Discrete Logarithms  

E-Print Network (OSTI)

an order of magnitude using such an analysis. Among the reasons for this are: · if a high-level language, keeping in mind that logg a is only determined modulo the multiplicative order of g. For general be extremely useful to chart the increase in difficulty of computing discrete logarithms as the field size

Gordon, Dan

37

Parallel Volume Computation of Massive Polyhedron Union  

E-Print Network (OSTI)

on chip · smaller greater electrical resistance ! · ==. · Serial processors have hit a wall. Franklin HW? · More processing faster clock speed · faster more electrical power · faster smaller features. · Iterate. Time depends on intermediate swell, and elementary intersection time. · Let P = size of union

Franklin, W. Randolph

38

Algorithms for VLSI Circuit Optimization and GPU-Based Parallelization  

E-Print Network (OSTI)

processing unit (GPGPU) technology provides massive parallel computing power. This research turns the complex computation task of circuit optimization into many subtasks processed by parallel threads. The proposed task partitioning and scheduling methods take...

Liu, Yifang

2010-07-14T23:59:59.000Z

39

Parallel MATLAB: Parallel For Loops  

E-Print Network (OSTI)

Parallel MATLAB: Parallel For Loops John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 69 #12;MATLAB Parallel Example ODE SWEEP Example FMINCON Example Conclusion 2 / 69 #12;INTRO: Parallel MATLAB Parallel MATLAB

Crawford, T. Daniel

40

Massive Hopfions  

E-Print Network (OSTI)

The Skyrme-Faddeev model is a (3+1)-dimensional model which has knotted, string-like, soliton solutions. In this paper we investigate a Skyrme-Faddeev model with an SO(3) symmetry breaking potential. We then rescale this model and take the mass to infinity. This infinite mass model is found to have compact knotted solutions. In all of the investigated massive models we find similar charged solutions as in the usual, m=0, model. We also find that their energies follow a similar power growth as the m=0 model.

David Foster

2010-12-12T23:59:59.000Z

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


41

Cluster Parallel Loops Part I. Preliminaries  

E-Print Network (OSTI)

;14­2 BIG CPU, BIG DATA he massively parallel Bitcoin mining program in Chapter 13 still doesn't take full advantage of the cluster's parallel processing capabilities. Each Bitcoin mining task uses all the cores on just one node. So on the 10-node tardis cluster, I have to mine 10 or more Bitcoins to fully utilize

Kaminsky, Alan

42

Hybrid Parallel Part I. Preliminaries  

E-Print Network (OSTI)

;13­2 BIG CPU, BIG DATA he massively parallel Bitcoin mining program in Chapter 11 doesn't nec essarily take each Bitcoin sequentially on a single core, I have to mine 40 or more Bitcoins to take full advantage of the cluster. If I mine fewer than 40 Bitcoins, some of the cores will be idle. That's not good. I want to put

Kaminsky, Alan

43

Scheduling of real-time communication network for parallel processing  

E-Print Network (OSTI)

As real-time applications become more and more complicated their demands of processing capacity can hardly be satisfied. Massively parallel computers, such as Intel Paragon, with their scalable architecture and tremendous processing power make them...

Li, Hung

2012-06-07T23:59:59.000Z

44

Parallel MATLAB at VT: Parallel For Loops  

E-Print Network (OSTI)

Parallel MATLAB at VT: Parallel For Loops John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 72 #12;MATLAB Parallel Example ODE SWEEP Example FMINCON Example Conclusion 2 / 72 #12;INTRO: Parallel MATLAB Parallel MATLAB

Crawford, T. Daniel

45

Parallel MATLAB at VT: Parallel For Loops  

E-Print Network (OSTI)

Parallel MATLAB at VT: Parallel For Loops John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 71 #12;MATLAB Parallel Example ODE SWEEP Example FMINCON Example Conclusion 2 / 71 #12;INTRO: Parallel MATLAB Parallel MATLAB

Crawford, T. Daniel

46

APPLAUSE: Applications Using the ElipSys Parallel CLP System  

E-Print Network (OSTI)

of Parallel Programming Us- ing Logic) Project is building major applications using the ElipSys par- allel, possibly massive, search spaces can be explored in parallel. 5 Environmental Monitoring and Control: Sys concerned with the monitoring and control of pollution in the Venice Lagoon as a demonstrator for the Venice

Panagiotis, Stamatopoulos

47

Parallel MATLAB at VT: Parallel For Loops  

E-Print Network (OSTI)

Parallel MATLAB at VT: Parallel For Loops John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 56 #12;Matlab Parallel ODE SWEEP Example MD Example Conclusion 2 / 56 #12;INTRO: Parallel Matlab In a previous lecture we

Crawford, T. Daniel

48

Stability of Solutions of Hydrodynamic Equations Describing the Scaling Limit of a Massive Piston in an  

E-Print Network (OSTI)

Stability of Solutions of Hydrodynamic Equations Describing the Scaling Limit of a Massive Piston of a system con- sisting of a massive piston immersed in an ideal gas of point particles in a box. We find of a system consisting of a piston of mass M moving parallel to the x-axis in a cube containing non

Chernov, Nikolai

49

Turbulent Transport Reduction by Zonal Flows: Massively Parallel Simulations  

Science Journals Connector (OSTI)

...University, Post Office Box 451,-Princeton, NJ 08543,-USA. * To whom correspondence should be addressed. Email: zlin@pppl.gov Turbulence shear suppression by E -B flows (plasma flows induced by an electric field perpendicular to a magnetic field...

Z. Lin; T. S. Hahm; W. W. Lee; W. M. Tang; R. B. White

1998-09-18T23:59:59.000Z

50

Artificial Neural Network on a Massively Parallel Associative Architecture  

Science Journals Connector (OSTI)

An implementation of a fully connected artificial neural network using the multi-layered perceptron model is described. The neural network is implemented on the ASP (Associative String ... Microsystems Ltd., base...

A. Krikelis

1990-01-01T23:59:59.000Z

51

Three-dimensional massively parallel electromagnetic inversion—I. Theory  

Science Journals Connector (OSTI)

......waste-site evaluations, mineral, oil, and gas exploration, and more recently reservoir...parameter Because of the computational cost of using an exact forward solution...will also serve as an accuracy benchmark on approxi- mate inverse methods......

G. A. Newman; D. L. Alumbaugh

1997-02-01T23:59:59.000Z

52

The utility coprocessor: massively parallel computation from the coffee shop  

Science Journals Connector (OSTI)

UCop, the "utility coprocessor," is middleware that makes it cheap and easy to achieve dramatic speedups of parallelizable, CPU-bound desktop applications using utility computing clusters in the cloud. To make UCop performant, we introduced techniques ...

John R. Douceur; Jeremy Elson; Jon Howell; Jacob R. Lorch

2010-06-01T23:59:59.000Z

53

Approximate inference for spatial functional data on massively parallel processors  

Science Journals Connector (OSTI)

With continually increasing data sizes, the relevance of the big n problem of classical likelihood approaches is greater than ever. The functional mixed-effects model is a well established class of models for analyzing functional data. Spatial functional ... Keywords: Functional data analysis, Functional mixed-effects model, GPU, Gaussian processes, Likelihood analysis, Operator approximations

Lars Lau Rakêt; Bo Markussen

2014-04-01T23:59:59.000Z

54

Massively parallel structured direct solver for equations describing ...  

E-Print Network (OSTI)

on a large domain, for a large number of different sources. ..... the symmetry axis is given by the third column of R?,?. ..... the green dashed line in figure ? ... of anisotropy in RTM and FWI has been widely recognized as important in real-

2011-10-17T23:59:59.000Z

55

Mapping the Hallmarks of Lung Adenocarcinoma with Massively Parallel Sequencing  

E-Print Network (OSTI)

Lung adenocarcinoma, the most common subtype of non-small cell lung cancer, is responsible for more than 500,000 deaths per year worldwide. Here, we report exome and genome sequences of 183 lung adenocarcinoma tumor/normal ...

Lander, Eric S.

56

Resummation of Massive Gravity  

SciTech Connect

We construct four-dimensional covariant nonlinear theories of massive gravity which are ghost-free in the decoupling limit to all orders. These theories resume explicitly all the nonlinear terms of an effective field theory of massive gravity. We show that away from the decoupling limit the Hamiltonian constraint is maintained at least up to and including quartic order in nonlinearities, hence excluding the possibility of the Boulware-Deser ghost up to this order. We also show that the same remains true to all orders in a similar toy model.

Rham, Claudia de [Department de Physique Theorique, Universite de Geneve, 24 Quai E. Ansermet, CH-1211 Geneve (Switzerland); Gabadadze, Gregory [Center for Cosmology and Particle Physics, Department of Physics, New York University, New York 10003 (United States); Tolley, Andrew J. [Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106 (United States)

2011-06-10T23:59:59.000Z

57

A novel polymeric microelectrode array for highly parallel, long-term neuronal culture and stimulation  

E-Print Network (OSTI)

Cell-based high-throughput screening is emerging as a disruptive technology in drug discovery; however, massively parallel electrical assaying of neurons and cardiomyocites has until now been prohibitively expensive. To ...

Talei Franzesi, Giovanni

2008-01-01T23:59:59.000Z

58

Massive Star Outflows  

E-Print Network (OSTI)

Molecular outflows in the form of wide-angle winds and/or well-collimated jets are associated with young stellar objects of all luminosities. Independent studies have established that the mass outflow rate is proportional to L_bol^0.6 for L_bol = 0.3 to 10^5 L_sun, suggesting that there is a strong link between accretion and outflow for a wide range of source luminosity and there is reasonable evidence that accretion-related processes are responsible for generating massive molecular flows from protostars up to spectral type B0. Beyond L_bol ~ 10^4 L_sun, O stars generate powerful wide-angle, ionized winds that can dramatically affect outflow morphology and even call into question the relationship between outflow and accretion. Recently Beuther & Shepherd (2005) proposed an evolutionary scenario in which massive protostellar flows (up to early B spectral type) begin collimated. Once the star reaches the Main Sequence, ionizing radiation may affect the balance between magnetic and plasma pressure, inducing changes in the flow morphology and energetics. Here I review the properties of outflows from young OB stars, discuss implications and observational tests of this proposed evolutionary scenario, and examine differences between low-mass and massive star formation.

D. S. Shepherd

2005-06-01T23:59:59.000Z

59

Parallel Batch Scripts  

NLE Websites -- All DOE Office Websites (Extended Search)

Parallel Batch Scripts Parallel Batch Scripts Parallel Batch Scripts Parallel Environments on Genepool You can run parallel jobs that use MPI or OpenMP on Genepool as long as you make the appropriate changes to your submission script! To investigate the parallel environments that are available on Genepool, you can use Command Description qconf -sp Show the configuration for the specified parallel environment. qconf -spl Show a list of all currently configured parallel environments. Basic Parallel Example If your job requires the default 5GB of memory per slot, you can do the following: #!/bin/bash # # == Set SGE options: # # -- ensure BASH is used # -- run the job in the current working directory (where qsub is called) #$ -cwd # -- run with the environment variables from the User's environment

60

Massive June Bug Emergence  

NLE Websites -- All DOE Office Websites (Extended Search)

Massive June Bug Emergence Massive June Bug Emergence Name: Cordell Location: N/A Country: N/A Date: N/A Question: We are infested with june bugs next to the street light near the end of my driveway. They have burrowed into the ground and underneath my driveway. Yesterday we shoveled 2/3 of a 33-gallon trash bag of just bugs. What can we spray or do to kill these june bugs? Replies: Not knowing which part of the country you are from and I could be wrong because of this fact buy this does not sound like June Bugs. This has to be a Circadia outbreak which are relatives to the June Bug. They run in 13, 17 or other year cycles and this depends upon the part of the country you are from. Ask a local garden center or naturalist and you'll probably see that this won't happen again for a number of years to come.

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


61

Parallelization of the Value-Iteration algorithm for  

E-Print Network (OSTI)

and stochastic environment. To determine the solution of a POMDP, algorithms with a running time in the PSPACE using the massive parallel processing power of modern Graphic Processing Units (GPU). Our experiments synchronization features are needed to exploit the full potential. #12;ii #12;Summary (Danish) Delvist

62

Massive neutrinos and cosmology  

E-Print Network (OSTI)

The present experimental results on neutrino flavour oscillations provide evidence for non-zero neutrino masses, but give no hint on their absolute mass scale, which is the target of beta decay and neutrinoless double-beta decay experiments. Crucial complementary information on neutrino masses can be obtained from the analysis of data on cosmological observables, such as the anisotropies of the cosmic microwave background or the distribution of large-scale structure. In this review we describe in detail how free-streaming massive neutrinos affect the evolution of cosmological perturbations. We summarize the current bounds on the sum of neutrino masses that can be derived from various combinations of cosmological data, including the most recent analysis by the WMAP team. We also discuss how future cosmological experiments are expected to be sensitive to neutrino masses well into the sub-eV range.

Julien Lesgourgues; Sergio Pastor

2006-05-29T23:59:59.000Z

63

Categorical Exclusion Determinations: North Carolina | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

April 9, 2010 April 9, 2010 CX-001794: Categorical Exclusion Determination Commercial Renewable Energy Systems - Charlotte Mecklenburg School Solar Thermal CX(s) Applied: B5.1 Date: 04/09/2010 Location(s): Cornelius, North Carolina Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory April 8, 2010 CX-001635: Categorical Exclusion Determination Solar American Institute Incubator - Semprius - Massively Parallel Microcell-Based Module Array CX(s) Applied: B3.6 Date: 04/08/2010 Location(s): Durham, North Carolina Office(s): Energy Efficiency and Renewable Energy, Golden Field Office April 7, 2010 CX-001432: Categorical Exclusion Determination Commercial Renewable Energy Systems - Gaston County Solid Waste Biogas Project CX(s) Applied: B1.15, A9, A11, B5.1

64

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

81 - 28590 of 28,904 results. 81 - 28590 of 28,904 results. Download CX-001635: Categorical Exclusion Determination Solar American Institute Incubator - Semprius - Massively Parallel Microcell-Based Module Array CX(s) Applied: B3.6 Date: 04/08/2010 Location(s): Durham, North Carolina Office(s): Energy Efficiency and Renewable Energy, Golden Field Office http://energy.gov/nepa/downloads/cx-001635-categorical-exclusion-determination Download CX-001560: Categorical Exclusion Determination Hydroelectric turbine at Water Treatment Plant American Recovery and Reinvestment Act Energy Efficiency and Conservation Block Grant Strategy Only CX(s) Applied: B5.1 Date: 03/31/2010 Location(s): Greensboro, North Carolina Office(s): Energy Efficiency and Renewable Energy, Golden Field Office http://energy.gov/nepa/downloads/cx-001560-categorical-exclusion-determination

65

RECIPIENT:Semprius  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Semprius Semprius u.s. DEPARTr-IEN T OF ENERGY EERE PROJECT MAN AGEMEN T CENT ER NEPA DETERMINATION Page 1 of2 STATE: NC PROJECT TITLE: SAl Incubator - Semprius - Massively Parallel Microcell-based Module Array; NREl Tracking No. 09- 036a Funding Opportunity Announcement Number Procur~mtnt Instrument Number NEPA Control Number elD Number NREL-09-036a G010337 Based on my review of the information concuning the proposed action, as Nf:PA Compliance Officer (authorized undcr DOE Order 45 I. IA), I have made the following determination: ex, EA, EIS APPENDIX ANI) NUMBER: Description: 83.6 Siting, construction (or modification), operation, and decommissioning of facilities for indoor bench-scale research projects and conventional laboratory operations (for example, preparation of chemical standards and sample analysis);

66

CX-001635: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

635: Categorical Exclusion Determination 635: Categorical Exclusion Determination CX-001635: Categorical Exclusion Determination Solar American Institute Incubator - Semprius - Massively Parallel Microcell-Based Module Array CX(s) Applied: B3.6 Date: 04/08/2010 Location(s): Durham, North Carolina Office(s): Energy Efficiency and Renewable Energy, Golden Field Office DOE funding would be used by National Renewable Energy Laboratory (NREL) to support the Solar American Initiative (SAl) Photovoltaic (PV) Technology Incubator. The program is structured to allow innovative approaches targeted at research and development of PV cells and module prototypes. The primary objective of this SAl PV Technology Incubator project is to shorten the timeline for companies to transition prototype and pre-commercial PV

67

The STAPL Parallel Container Framework  

E-Print Network (OSTI)

The Standard Template Adaptive Parallel Library (STAPL) is a parallel programming infrastructure that extends C with support for parallelism. STAPL provides a run-time system, a collection of distributed data structures (pContainers) and parallel...

Tanase, Ilie Gabriel

2012-02-14T23:59:59.000Z

68

Parallel integrated thermal management  

DOE Patents (OSTI)

Embodiments discussed herein are directed to managing the heat content of two vehicle subsystems through a single coolant loop having parallel branches for each subsystem.

Bennion, Kevin; Thornton, Matthew

2014-08-19T23:59:59.000Z

69

Massive sulphides and plate tectonics  

Science Journals Connector (OSTI)

... presence of a suitable depositional site, which is commonly on the sea floor7'12.This geothermal model seems to account for the salient features of massive sulphides.

M. SOLOMON

1974-06-28T23:59:59.000Z

70

An efficient parallel algorithm for matrix-vector multiplication  

SciTech Connect

The multiplication of a vector by a matrix is the kernel computation of many algorithms in scientific computation. A fast parallel algorithm for this calculation is therefore necessary if one is to make full use of the new generation of parallel supercomputers. This paper presents a high performance, parallel matrix-vector multiplication algorithm that is particularly well suited to hypercube multiprocessors. For an n x n matrix on p processors, the communication cost of this algorithm is O(n/[radical]p + log(p)), independent of the matrix sparsity pattern. The performance of the algorithm is demonstrated by employing it as the kernel in the well-known NAS conjugate gradient benchmark, where a run time of 6.09 seconds was observed. This is the best published performance on this benchmark achieved to date using a massively parallel supercomputer.

Hendrickson, B.; Leland, R.; Plimpton, S.

1993-03-01T23:59:59.000Z

71

Parallel programming with PCN  

SciTech Connect

PCN is a system for developing and executing parallel programs. It comprises a high-level programming language, tools for developing and debugging programs in this language, and interfaces to Fortran and C that allow the reuse of existing code in multilingual parallel programs. Programs developed using PCN are portable across many different workstations, networks, and parallel computers. This document provides all the information required to develop parallel programs with the PCN programming system. In includes both tutorial and reference material. It also presents the basic concepts that underly PCN, particularly where these are likely to be unfamiliar to the reader, and provides pointers to other documentation on the PCN language, programming techniques, and tools. PCN is in the public domain. The latest version of both the software and this manual can be obtained by anonymous FTP from Argonne National Laboratory in the directory pub/pcn at info.mcs.anl.gov (c.f. Appendix A).

Foster, I.; Tuecke, S.

1991-12-01T23:59:59.000Z

72

Massive photons and Lorentz violation  

E-Print Network (OSTI)

All quadratic translation- and gauge-invariant photon operators for Lorentz breakdown are included into the Stueckelberg Lagrangian for massive photons in a generalized \\xi-gauge. The corresponding dispersion relation and tree-level propagator are determined exactly, and some leading-order results are derived. The question of how to include such Lorentz-violating effects into a perturbative quantum-field expansion is addressed. Applications of these results within Lorentz-breaking quantum field theories include the regularization of infrared divergences as well as the free propagation of massive vector bosons.

Mauro Cambiaso; Ralf Lehnert; Robertus Potting

2012-01-14T23:59:59.000Z

73

Parallel Composition Communication and Allow Hiding Parallel Processes  

E-Print Network (OSTI)

Parallel Composition Challenge (Dish1+Dish2) || Coke ? = (Dish1 || Coke)+(Dish2 || Coke) Mousavi: Parallel Composition Challenge (Dish1+Dish2) || Coke ? = (Dish1 || Coke)+(Dish2 || Coke) Faron Moller's Result Parallel Parallel Composition and |: Raisons d'^etre (Dish1 + Dish2) Coke (Dish1 Coke) + (Dish2 Coke) (Dish1 + Dish

Mousavi, Mohammad

74

Parallel Matlab MIT Lincoln Laboratory  

E-Print Network (OSTI)

Slide-1 Parallel Matlab MIT Lincoln Laboratory Parallel Matlab: The Next Generation Dr. Jeremy Lincoln LaboratorySlide-2 Parallel Matlab · Motivation · Challenges Outline · Introduction · Approach · Performance Results · Future Work and Summary #12;MIT Lincoln LaboratorySlide-3 Parallel Matlab Motivation: Do

Kepner, Jeremy

75

Elegant Parallelization Progress Report  

NLE Websites -- All DOE Office Websites (Extended Search)

Elegant Parallelization Progress Report Elegant Parallelization Progress Report 10/24/07 Yusong Wang Michael Borland Hairong Shang Robert Soliday Elegant Parallelization Progress Report Y. Wang, 10/24/07 Simulations with a Large Number of Particles  Recent development  Each slave is allocated memory only for the portion of particles it owns, instead of the memory required for all the particles  On a cluster of quad-cores, configured master to be run on a single node without sharing memory with other slave nodes to allow maximal number of particles to be simulated ( master holds all the particles information for reading and writing)  Current capability and limitations  Simulated with 60 million particles on apex cluster  Can't simulate with 100 million or more particles because of the

76

Parallel optical sampler  

SciTech Connect

An optical sampler includes a first and second 1.times.n optical beam splitters splitting an input optical sampling signal and an optical analog input signal into n parallel channels, respectively, a plurality of optical delay elements providing n parallel delayed input optical sampling signals, n photodiodes converting the n parallel optical analog input signals into n respective electrical output signals, and n optical modulators modulating the input optical sampling signal or the optical analog input signal by the respective electrical output signals, and providing n successive optical samples of the optical analog input signal. A plurality of output photodiodes and eADCs convert the n successive optical samples to n successive digital samples. The optical modulator may be a photodiode interconnected Mach-Zehnder Modulator. A method of sampling the optical analog input signal is disclosed.

Tauke-Pedretti, Anna; Skogen, Erik J; Vawter, Gregory A

2014-05-20T23:59:59.000Z

77

Massivizing Online Games: Distributed Computing Challenges and  

E-Print Network (OSTI)

Massivizing Online Social Games Scheduling in IaaS Clouds Gamification in Higher Education May 9 May 27 June 5

Iosup, Alexandru

78

Final Report -- Center for Programmng Models for Scalable Parallel Computing (UIUC subgroup)  

SciTech Connect

The mission of the Center for Scalable Programming Models (Pmodels) was to create new ways of programming parallel computers that are much easier for humans to conceptualize, that allow programs to be written, updated and debugged quickly, and that run extremely efficiently---even on computers with thousands or even millions of processors. At UIUC, our work for Pmodels focused on support for I/O in a massively parallel environment, and included both research and technology transfer activities.

Marianne Winslett; Michael Folk

2007-03-31T23:59:59.000Z

79

X-ray Emission from Massive Stars  

E-Print Network (OSTI)

X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore be related to the production of X-rays on massive stars. If so, massive stars' X-rays are much different than those found our own Sun and other cooler stars like the Sun that produce X-rays via magnetic activity

Cohen, David

80

Massive Stars and their Supernovae  

E-Print Network (OSTI)

Massive stars and their supernovae are prominent sources of radioactive isotopes, the observations of which thus can help to improve our astrophysical models of those. Our understanding of stellar evolution and the final explosive endpoints such as supernovae or hypernovae or gamma-ray bursts relies on the combination of magneto-hydrodynamics, energy generation due to nuclear reactions accompanying composition changes, radiation transport, and thermodynamic properties (such as the equation of state of stellar matter). Nuclear energy production includes all nuclear reactions triggered during stellar evolution and explosive end stages, also among unstable isotopes produced on the way. Radiation transport covers atomic physics (e.g. opacities) for photon transport, but also nuclear physics and neutrino nucleon/nucleus interactions in late phases and core collapse. Here we want to focus on the astrophysical aspects, i.e. a description of the evolution of massive stars and their endpoints, with a special emphasis ...

Thielemann, Friedrich-Karl; Liebendörfer, Matthias; Diehl, Roland; 10.1007/978-3-642-12698-7_4

2010-01-01T23:59:59.000Z

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


81

Parallel computing in atmospheric chemistry models  

SciTech Connect

Studies of atmospheric chemistry are of high scientific interest, involve computations that are complex and intense, and require enormous amounts of I/O. Current supercomputer computational capabilities are limiting the studies of stratospheric and tropospheric chemistry and will certainly not be able to handle the upcoming coupled chemistry/climate models. To enable such calculations, the authors have developed a computing framework that allows computations on a wide range of computational platforms, including massively parallel machines. Because of the fast paced changes in this field, the modeling framework and scientific modules have been developed to be highly portable and efficient. Here, the authors present the important features of the framework and focus on the atmospheric chemistry module, named IMPACT, and its capabilities. Applications of IMPACT to aircraft studies will be presented.

Rotman, D. [Lawrence Livermore National Lab., CA (United States). Atmospheric Sciences Div.

1996-02-01T23:59:59.000Z

82

Allinea DDT as a Parallel Debugging Alternative to Totalview  

SciTech Connect

Totalview, from the Etnus Corporation, is a sophisticated and feature rich software debugger for parallel applications. As Totalview has gained in popularity and market share its pricing model has increased to the point where it is often prohibitively expensive for massively parallel supercomputers. Additionally, many of Totalview's advanced features are not used by members of the scientific computing community. For these reasons, supercomputing centers have begun to search for a basic parallel debugging tool which can be used as an alternative to Totalview. As the cost and complexity of Totalview has increased over the years, scientific computing centers have started searching for a viable parallel debugging alternative. DDT (Distributed Debugging Tool) from Allinea Software is a relatively new parallel debugging tool which aims to provide much of the same functionality as Totalview. This review outlines the basic features and limitations of DDT to determine if it can be a reasonable substitute for Totalview. DDT was tested on the NERSC platforms Bassi, Seaborg, Jacquard and Davinci with Fortran90, C, and C++ codes using MPI and OpenMP for parallelism.

Antypas, K.B.

2007-03-05T23:59:59.000Z

83

Parallel programming with PCN  

SciTech Connect

PCN is a system for developing and executing parallel programs. It comprises a high-level programming language, tools for developing and debugging programs in this language, and interfaces to Fortran and Cthat allow the reuse of existing code in multilingual parallel programs. Programs developed using PCN are portable across many different workstations, networks, and parallel computers. This document provides all the information required to develop parallel programs with the PCN programming system. It includes both tutorial and reference material. It also presents the basic concepts that underlie PCN, particularly where these are likely to be unfamiliar to the reader, and provides pointers to other documentation on the PCN language, programming techniques, and tools. PCN is in the public domain. The latest version of both the software and this manual can be obtained by anonymous ftp from Argonne National Laboratory in the directory pub/pcn at info.mcs. ani.gov (cf. Appendix A). This version of this document describes PCN version 2.0, a major revision of the PCN programming system. It supersedes earlier versions of this report.

Foster, I.; Tuecke, S.

1993-01-01T23:59:59.000Z

84

Parallelism Extraction Algorithm from Stream-Based Processing Flow Applying Spanning Tree  

Science Journals Connector (OSTI)

Manycore architecture promotes a massively parallel computing on the accelerators. Especially GPU is one of the main series of the high performance computing, which is also employed by top supercomputers in the world. The programming method on such accelerators ... Keywords: High Performance Computing, Stream Computing, GPUs, Caravela, Spanning Tree Algorithm

Guyue Wang, Shinichi Yamagiwa, Koichi Wada

2014-05-01T23:59:59.000Z

85

Synchronization of parallel programs  

SciTech Connect

Modular and parallel programming languages and the development of distributed architectures make it possible for hardware to produce much higher operating speeds than could previously be achieved through sequential processing. Executing these cooperating, concurrent processes demands that new specification and implementation techniques be developed. This book proposes a method for expressing typical cooperation and competition problems, as well as different synchronization and communication methods for implementing them. Using a general abstract expression to state synchronization constraints between parallel processes, the authors then choose either a centralized or a distributed implementation for the targeted system. Each of these implementations is illustrated with examples drawn from classic problems, and one informal case study (management of access to a swimming pool) is used to compare the various approaches.

Andre, F.; Herman, D.; Verjus, J.P.

1985-01-01T23:59:59.000Z

86

On parallel machine scheduling 1  

E-Print Network (OSTI)

On parallel machine scheduling 1 machines with setup times. The setup has to be performed by a single server. The objective is to minimize even for the case of two identical parallel machines. This paper presents a pseudopolynomial

Magdeburg, Universität

87

Parallel Worldline Numerics: Implementation and Error Analysis  

E-Print Network (OSTI)

We give an overview of the worldline numerics technique, and discuss the parallel CUDA implementation of a worldline numerics algorithm. In the worldline numerics technique, we wish to generate an ensemble of representative closed-loop particle trajectories, and use these to compute an approximate average value for Wilson loops. We show how this can be done with a specific emphasis on cylindrically symmetric magnetic fields. The fine-grained, massive parallelism provided by the GPU architecture results in considerable speedup in computing Wilson loop averages. Furthermore, we give a brief overview of uncertainty analysis in the worldline numerics method. There are uncertainties from discretizing each loop, and from using a statistical ensemble of representative loops. The former can be minimized so that the latter dominates. However, determining the statistical uncertainties is complicated by two subtleties. Firstly, the distributions generated by the worldline ensembles are highly non-Gaussian, and so the standard error in the mean is not a good measure of the statistical uncertainty. Secondly, because the same ensemble of worldlines is used to compute the Wilson loops at different values of $T$ and $x_\\mathrm{ cm}$, the uncertainties associated with each computed value of the integrand are strongly correlated. We recommend a form of jackknife analysis which deals with both of these problems.

Dan Mazur; Jeremy S. Heyl

2014-07-28T23:59:59.000Z

88

A Massive Stellar Burst Before the Supernova  

NLE Websites -- All DOE Office Websites (Extended Search)

massive stars shed huge amounts of material in a "penultimate outburst" before final detonation as supernovae. A focused search for Type IIn SN precursor bursts, conducted by Eran...

89

Massive Variability Surveys from Venezuela  

E-Print Network (OSTI)

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

Cesar Briceno

2003-04-03T23:59:59.000Z

90

Stable massive particles at colliders  

SciTech Connect

We review the theoretical motivations and experimental status of searches for stable massive particles (SMPs) which could be sufficiently long-lived as to be directly detected at collider experiments. The discovery of such particles would address a number of important questions in modern physics including the origin and composition of dark matter in the universe and the unification of the fundamental forces. This review describes the techniques used in SMP-searches at collider experiments and the limits so far obtained on the production of SMPs which possess various colour, electric and magnetic charge quantum numbers. We also describe theoretical scenarios which predict SMPs, the phenomenology needed to model their production at colliders and interactions with matter. In addition, the interplay between collider searches and open questions in cosmology such as dark matter composition are addressed.

Fairbairn, M.; /Stockholm U.; Kraan, A.C.; /Pennsylvania U.; Milstead, D.A.; /Stockholm U.; Sjostrand, T.; /Lund U.; Skands, P.; /Fermilab; Sloan, T.; /Lancaster U.; ,

2006-11-01T23:59:59.000Z

91

Alexandru Iosup Parallel and Distributed Systems Group  

E-Print Network (OSTI)

Engineering Center (TCE), Haifa, IL IaaS Cloud Benchmarking Massivizing Online Social Games Gamification

Iosup, Alexandru

92

X-ray Emission from Massive Stars  

E-Print Network (OSTI)

X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore #12;What is the mechanism by which massive stars produce x-rays? New results from the Chandra X-ray Observatory ­ high-resolution x-ray spectroscopy: measuring Doppler broadening in emission lines Testing

Cohen, David

93

A pattern-supported parallelization approach  

Science Journals Connector (OSTI)

In the embedded systems domain a trend towards multi-and many-core processors is evident. For the exploitation of these additional processing elements parallel software is inevitable. The pattern-supported parallelization approach, which is introduced ... Keywords: algorithmic skeletons, design patterns, embedded systems, extended UML2 model, model-based parallelization, parallel design patterns, parallel programming, parallelization

Ralf Jahr; Mike Gerdes; Theo Ungerer

2013-02-01T23:59:59.000Z

94

Parallel Monte Carlo reactor neutronics  

SciTech Connect

The issues affecting implementation of parallel algorithms for large-scale engineering Monte Carlo neutron transport simulations are discussed. For nuclear reactor calculations, these include load balancing, recoding effort, reproducibility, domain decomposition techniques, I/O minimization, and strategies for different parallel architectures. Two codes were parallelized and tested for performance. The architectures employed include SIMD, MIMD-distributed memory, and workstation network with uneven interactive load. Speedups linear with the number of nodes were achieved.

Blomquist, R.N.; Brown, F.B.

1994-03-01T23:59:59.000Z

95

Seismic Studies of a Massive Hydraulic Fracturing Experiment...  

Open Energy Info (EERE)

a Massive Hydraulic Fracturing Experiment Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Seismic Studies of a Massive Hydraulic Fracturing...

96

Massive Hanford Test Reactor Removed - Plutonium Recycle Test...  

Office of Environmental Management (EM)

Massive Hanford Test Reactor Removed - Plutonium Recycle Test Reactor removed from Hanford's 300 Area Massive Hanford Test Reactor Removed - Plutonium Recycle Test Reactor removed...

97

Binary Capture Rates for Massive Protostars  

E-Print Network (OSTI)

The high multiplicity of massive stars in dense, young clusters is established early in their evolution. The mechanism behind this remains unresolved. Recent results suggest that massive protostars may capture companions through disk interactions with much higher efficiency than their solar mass counterparts. However, this conclusion is based on analytic determinations of capture rates and estimates of the robustness of the resulting binaries. We present the results of coupled n-body and SPH simulations of star-disk encounters to further test the idea that disk-captured binaries contribute to the observed multiplicity of massive stars.

Nickolas Moeckel; John Bally

2007-04-09T23:59:59.000Z

98

Checkpointing strategies for parallel jobs  

Science Journals Connector (OSTI)

This work provides an analysis of checkpointing strategies for minimizing expected job execution times in an environment that is subject to processor failures. In the case of both sequential and parallel jobs, we give the optimal solution for exponentially ... Keywords: checkpointing, fault-tolerance, parallel job, sequential job

Marin Bougeret; Henri Casanova; Mikael Rabie; Yves Robert; Frédéric Vivien

2011-11-01T23:59:59.000Z

99

Architecture, implementation and parallelization of the software to search for periodic gravitational wave signals  

E-Print Network (OSTI)

The parallelization, design and scalability of the \\sky code to search for periodic gravitational waves from rotating neutron stars is discussed. The code is based on an efficient implementation of the F-statistic using the Fast Fourier Transform algorithm. To perform an analysis of data from the advanced LIGO and Virgo gravitational wave detectors' network, which will start operating in 2015, hundreds of millions of CPU hours will be required - the code utilizing the potential of massively parallel supercomputers is therefore mandatory. We have parallelized the code using the Message Passing Interface standard, implemented a mechanism for combining the searches at different sky-positions and frequency bands into one extremely scalable program. The parallel I/O interface is used to escape bottlenecks, when writing the generated data into file system. This allowed to develop a highly scalable computation code, which would enable the data analysis at large scales on acceptable time scales. Benchmarking of the c...

Poghosyan, Gevorg; Streit, Achim; Bejger, Micha?; Królak, Andrzej

2014-01-01T23:59:59.000Z

100

Massively-Parallel Spectral Element Large Eddy Simulation of a Ring-Type Gas Turbine Combustor  

E-Print Network (OSTI)

-Stokes . . . . . . . . . . . . . 28 D. NEK5000 . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 E. Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 F. Mesh Generation . . . . . . . . . . . . . . . . . . . . . . . 36 III RESULTS AND DISCUSSION... in consumer vehicles and creating faster commercial jets. While discovering new energy resources in itself is an important concept, the rate of energy consumption, or power, is perhaps equally important. Power generation is what drives the modern world...

Camp, Joshua Lane

2012-07-16T23:59:59.000Z

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


101

Advancing predictive models for particulate formation in turbulent flames via massively parallel direct numerical simulations  

Science Journals Connector (OSTI)

...147. The pressure is atmospheric. The gas-phase hydrodynamics...formulation is the high-order inter...aeroderivative combustors, while the...fraction is highest (figure-4...scavenging gas-phase precursors...flame of natural gas and air...based on the high Da number...

2014-01-01T23:59:59.000Z

102

Massively parallel computing simulation of fluid flow in the unsaturated zone of Yucca Mountain, Nevada  

E-Print Network (OSTI)

Central Block Area, Yucca Mountain, Nye County, Nevada. Mapunsaturated zone, Yucca Mountain, Nevada. Water-Resourcesisotope distributions at Yucca Mountain. Sandia National

Zhang, Keni; Wu, Yu-Shu; Bodvarsson, G.S.

2001-01-01T23:59:59.000Z

103

Massively Parallel Spectral Element Large Eddy Simulation of a Turbulent Channel Using Wall Models  

E-Print Network (OSTI)

the strength and ability to push forward and succeed. I owe you guys everything and nobody could ask for a better family. I love you all. iv NOMENCLATURE CFD Computational Fluid Dynamics DNS Direct Numerical Simulation RANS Reynolds Averaged Navier...-Stokes LES Large Eddy Simulation FEM Finite Element Method SEM Spectral Element Method SGS Sub-Grid Scale TLM Two Layer Method Re Reynolds Number Re Friction Reynolds Number U1 Characteristic Velocity GLL Gauss-Lobatto-Legendre Cs Smagorinski Coe...

Rabau, Joshua I

2013-05-01T23:59:59.000Z

104

Advancing predictive models for particulate formation in turbulent flames via massively parallel direct numerical simulations  

Science Journals Connector (OSTI)

...gaseous flames in gas turbine combustion chambers...using a flamelet/progress variable approach...flame of natural gas. Combust. Flame...and R Suntz. 2002 Progress in characterization...calculations. Technical report, University of Technology...

2014-01-01T23:59:59.000Z

105

Domain-specific translator and optimizer for massive on- chip parallelism  

E-Print Network (OSTI)

Trends in Computer Architecture . . . . . . . . . . 2.1.1E. Moore. Readings in computer architecture. cramming moreLectures on Computer Architecture. Morgan & Claypool

Unat, Didem

2012-01-01T23:59:59.000Z

106

Simulation and emulation of massively parallel processor for solving constraint satisfaction problems based on oracles.  

E-Print Network (OSTI)

?? Most part of my thesis is devoted to efficient automated logic synthesis of oracle processors. These Oracle Processors are of interest to several modern… (more)

Chaudhari, Gunavant Dinkar

2011-01-01T23:59:59.000Z

107

Massively-Parallel Simulation of Biochemical Systems Jens Ackermann Paul Baecher Thorsten Franzel  

E-Print Network (OSTI)

derivatives, and computing standard measures of complex dynamics like the Lyapunov exponent. 1 Introduction paradigms. Our system can automatically compile standard SBML files into CUDA code, using analytic]. Such parameter spaces are generally high-dimensional and pose therefore a difficult optimization problem [Ham05

Goesele, Michael

108

Smith-Waterman Sequence Alignment For Massively Parallel High-Performance Computing Architectures.  

E-Print Network (OSTI)

?? This research addresses one of the most often used tools in bioinformatics, sequence alignment. The increasing growth and complexity of high-performance computing as well… (more)

Steinfadt, Shannon Irene

2010-01-01T23:59:59.000Z

109

Non-invasive prenatal diagnosis by massively parallel sequencing of maternal plasma DNA  

Science Journals Connector (OSTI)

...capture system is able to focus the sequencing power...foetal DNA in maternal plasma are incorporated into...foetal DNA in maternal plasma would play an increasingly...His research interests focus on the biology and diagnostic...cell-free nucleic acids in plasma. In particular, he...

2012-01-01T23:59:59.000Z

110

Identification of radiation-induced microRNA transcriptome by next-generation massively parallel sequencing  

Science Journals Connector (OSTI)

......induction of DNA damage and repair, cell cycle perturbation...performed using Illumina processing pipeline software (version 1.5...homologous recombination-mediated repair, and renders cells hypersensitive...Chaudhry MA . Base excision repair of ionizing radiation-induced......

M. Ahmad Chaudhry; Romaica A. Omaruddin; Christopher D. Brumbaugh; Muhammad A. Tariq; Nader Pourmand

2013-09-01T23:59:59.000Z

111

A dynamic grouping strategy for implementation of the particle filter on a massively parallel computer  

E-Print Network (OSTI)

computer Shin'ya Nakano The Institute of Statistical Mathematics Tachikawa, Tokyo, Japan. shiny@ism.ac.jp Tomoyuki Higuchi The Institute of Statistical Mathematics Tachikawa, Tokyo, Japan. higuchi

Nakano, Shin'ya

112

Massive Stellar Clusters in Interacting Galaxies  

E-Print Network (OSTI)

Massive clusters are now seen to form easily in interacting and merging galaxies, making these excellent environments for studying the properties of young clusters. New observations of the Antennae (NGC 4038/39) show that the most luminous young clusters do not have a measurable tidal radius. Most observations suggest that the luminosity function (LF) and mass functions of young clusters are single power laws. However, there are many uncertainties at the faint end of the LF. For example, contamination from massive stars may be important. The shape and evolution of the LF, and more fundamentally, the mass function, of massive clusters had implications for our understanding of both the formation and the destruction of massive stellar clusters.

B. W. Miller

1999-12-21T23:59:59.000Z

113

Casimir Pistons for Massive Scalar Fields  

E-Print Network (OSTI)

The Casimir force on two-dimensional pistons for massive scalar fields with both Dirichlet and hybrid boundary conditions is computed. The physical result is obtained by making use of generalized $\\zeta$-function regularization technique. The influence of the mass and the position of the piston in the force is studied graphically. The Casimir force for massive scalar field is compared to that for massless scalar field.

Xiang-hua Zhai; Yan-yan Zhang; Xin-zhou Li

2008-08-01T23:59:59.000Z

114

Parallel processing for control applications  

SciTech Connect

Parallel processing has been a topic of discussion in computer science circles for decades. Using more than one single computer to control a process has many advantages that compensate for the additional cost. Initially multiple computers were used to attain higher speeds. A single cpu could not perform all of the operations necessary for real time operation. As technology progressed and cpu's became faster, the speed issue became less significant. The additional processing capabilities however continue to make high speeds an attractive element of parallel processing. Another reason for multiple processors is reliability. For the purpose of this discussion, reliability and robustness will be the focal paint. Most contemporary conceptions of parallel processing include visions of hundreds of single computers networked to provide 'computing power'. Indeed our own teraflop machines are built from large numbers of computers configured in a network (and thus limited by the network). There are many approaches to parallel configfirations and this presentation offers something slightly different from the contemporary networked model. In the world of embedded computers, which is a pervasive force in contemporary computer controls, there are many single chip computers available. If one backs away from the PC based parallel computing model and considers the possibilities of a parallel control device based on multiple single chip computers, a new area of possibilities becomes apparent. This study will look at the use of multiple single chip computers in a parallel configuration with emphasis placed on maximum reliability.

Telford, J. W. (John W.)

2001-01-01T23:59:59.000Z

115

Alexandru Iosup Parallel and Distributed Systems Group  

E-Print Network (OSTI)

Online Games: High Performance Computing and High Quality Time 1 Massivizing Social Games: High used to be art, may now be computing Massivizing Social Games: High Performance Computing and High,000,000 active players Massivizing Social Games: High Performance Computing and High Quality Time ­ A. Iosup 3

Iosup, Alexandru

116

Scha's Parallel Lines Bernhard Nickel  

E-Print Network (OSTI)

Scha's Parallel Lines Bernhard Nickel May 10, 2010 1 Introduction Scha (1981) has a famous example) The single lines run parallel to the double lines. 3 Code for Figure 1 \\begin{figure} \\centering \\setlength{\\unitlength}{.5in} \\begin{picture}(6,4) % first square \\put(0,4){\\line(1,0){4}}% \\put(0,1){\\line(1,0){4}}% \\put(0

Nickel, Bernhard

117

Endpoint-based parallel data processing in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Endpoint-based parallel data processing in a parallel active messaging interface ('PAMI') of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes coupled for data communications through the PAMI, including establishing a data communications geometry, the geometry specifying, for tasks representing processes of execution of the parallel application, a set of endpoints that are used in collective operations of the PAMI including a plurality of endpoints for one of the tasks; receiving in endpoints of the geometry an instruction for a collective operation; and executing the instruction for a collective opeartion through the endpoints in dependence upon the geometry, including dividing data communications operations among the plurality of endpoints for one of the tasks.

Archer, Charles J; Blocksome, Michael E; Ratterman, Joseph D; Smith, Brian E

2014-02-11T23:59:59.000Z

118

Endpoint-based parallel data processing in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Endpoint-based parallel data processing in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes coupled for data communications through the PAMI, including establishing a data communications geometry, the geometry specifying, for tasks representing processes of execution of the parallel application, a set of endpoints that are used in collective operations of the PAMI including a plurality of endpoints for one of the tasks; receiving in endpoints of the geometry an instruction for a collective operation; and executing the instruction for a collective operation through the endpoints in dependence upon the geometry, including dividing data communications operations among the plurality of endpoints for one of the tasks.

Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

2014-08-12T23:59:59.000Z

119

SED modeling of Young Massive Stars  

E-Print Network (OSTI)

In this contribution, I review the applications and potential limitations of the spectral energy distribution fitting tool that I have developed, with a strong emphasis on the limits to which this tool can be used to improve our understanding of massive star formation. I discuss why our current grid of models cannot be used to distinguish between the several competing theories of massive star formation. I also discuss stellar mass determinations, artificial correlations between parameters in the grid of models, multiplicity, confusion, dust assumptions, and unique fits. I briefly review the improvements we intend to carry out for our next grid of models, which will eliminate many of these limitations. Finally, I show examples of applications of this tool to massive young stars.

Thomas P. Robitaille

2007-11-27T23:59:59.000Z

120

Growth histories in bimetric massive gravity  

SciTech Connect

We perform cosmological perturbation theory in Hassan-Rosen bimetric gravity for general homogeneous and isotropic backgrounds. In the de Sitter approximation, we obtain decoupled sets of massless and massive scalar gravitational fluctuations. Matter perturbations then evolve like in Einstein gravity. We perturb the future de Sitter regime by the ratio of matter to dark energy, producing quasi-de Sitter space. In this more general setting the massive and massless fluctuations mix. We argue that in the quasi-de Sitter regime, the growth of structure in bimetric gravity differs from that of Einstein gravity.

Berg, Marcus; Buchberger, Igor [Department of Physics, Karlstad University, 651 88 Karlstad (Sweden); Enander, Jonas; Mörtsell, Edvard; Sjörs, Stefan, E-mail: marcus.berg@kau.se, E-mail: igor.buchberger@kau.se, E-mail: enander@fysik.su.se, E-mail: edvard@fysik.su.se, E-mail: stefans@fysik.su.se [Oskar Klein Center, Stockholm University, Albanova University Center, 106 91 Stockholm (Sweden)

2012-12-01T23:59:59.000Z

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


121

Invitation to embarrassingly parallel computing  

Science Journals Connector (OSTI)

A surprising number of physical systems problems are well suited to “embarrassingly parallel" computations which do not require complicated algorithms or specialized hardware. As faculty and students at small institutions we are readily incorporating parallel computing in diverse levels of our curricula and are embracing the opportunity to utilize high performance computing to do cutting edge research. We describe three typical examples: spatiotemporal patterns of one-way coupled oscillators ray-tracing in curved spacetime and solar escape as a three-body problem.

Barbara J. Breen; Christine E. Weidert; John F. Lindner; Lisa May Walker; Kasey Kelly; Evan Heidtmann

2008-01-01T23:59:59.000Z

122

New Candidate Massive Clusters from 2MASS  

E-Print Network (OSTI)

Massive stars are important for the evolution of the interstellar medium. The detailed study of their properties (such as mass loss, rotation, magnetic fields) is enormously facilitated by samples of these objects in young massive galactic star clusters. Using 2MASS we have searched for so far unknown candidates of red supergiant clusters along the Galactic Plane. Utilising deep high resolution UKIDSS GPS and VISTA VVV data to study colour-magnitude diagrams, we uncover six new massive cluster candidates in the inner Galaxy. If spectroscopically confirmed as real clusters, two of them could be part of the Scutum-Complex. One cluster candidate has a number of potential red supergiant members comparable to RSGC1 and 3. Our investigation of UKIDSS data reveals for the first time the main sequence of the massive cluster RSGC2. The stars of the sequence show an increased projected density at the same position as the known red supergiants in the cluster and have E(J-K)=1.6mag. This either indicates an unusual extin...

Froebrich, D

2013-01-01T23:59:59.000Z

123

Parallel continuation-based global optimization for molecular conformation and protein folding  

SciTech Connect

This paper presents the authors` recent work on developing parallel algorithms and software for solving the global minimization problem for molecular conformation, especially protein folding. Global minimization problems are difficult to solve when the objective functions have many local minimizers, such as the energy functions for protein folding. In their approach, to avoid directly minimizing a ``difficult`` function, a special integral transformation is introduced to transform the function into a class of gradually deformed, but ``smoother`` or ``easier`` functions. An optimization procedure is then applied to the new functions successively, to trace their solutions back to the original function. The method can be applied to a large class of nonlinear partially separable functions including energy functions for molecular conformation and protein folding. Mathematical theory for the method, as a special continuation approach to global optimization, is established. Algorithms with different solution tracing strategies are developed. Different levels of parallelism are exploited for the implementation of the algorithms on massively parallel architectures.

Coleman, T.F.; Wu, Z. [Cornell Univ., Ithaca, NY (United States)

1994-12-31T23:59:59.000Z

124

Dark/visible parallel universes and Big Bang nucleosynthesis  

SciTech Connect

We develop a model for visible matter-dark matter interaction based on the exchange of a massive gray boson called herein the Mulato. Our model hinges on the assumption that all known particles in the visible matter have their counterparts in the dark matter. We postulate six families of particles five of which are dark. This leads to the unavoidable postulation of six parallel worlds, the visible one and five invisible worlds. A close study of big bang nucleosynthesis (BBN), baryon asymmetries, cosmic microwave background (CMB) bounds, galaxy dynamics, together with the Standard Model assumptions, help us to set a limit on the mass and width of the new gauge boson. Modification of the statistics underlying the kinetic energy distribution of particles during the BBN is also discussed. The changes in reaction rates during the BBN due to a departure from the Debye-Hueckel electron screening model is also investigated.

Bertulani, C. A.; Frederico, T.; Fuqua, J.; Hussein, M. S.; Oliveira, O.; Paula, W. de [Department of Physics and Astronomy, Texas A and M University-Commerce, Commerce TX 75429 (United States); Departamento de Fisica, Instituto Tecnologico de Aeronautica, DCTA 12.228-900, Sao Jose dos Campos, SP (Brazil); Department of Physics and Astronomy, Texas A and M University-Commerce, Commerce TX 75429 (United States); Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05314-970 Sao Paulo, SP (Brazil); Departamento de Fisica, Instituto Tecnologico de Aeronautica, DCTA 12.228-900, Sao Jose dos Campos, SP, Brazil and Departamento de Fisica, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Departamento de Fisica, Instituto Tecnologico de Aeronautica, DCTA 12.228-900, Sao Jose dos Campos, SP (Brazil)

2012-11-20T23:59:59.000Z

125

Dark/visible parallel universes and Big Bang nucleosynthesis  

Science Journals Connector (OSTI)

We develop a model for visible matter-dark matter interaction based on the exchange of a massive gray boson called herein the Mulato. Our model hinges on the assumption that all known particles in the visible matter have their counterparts in the dark matter. We postulate six families of particles five of which are dark. This leads to the unavoidable postulation of six parallel worlds the visible one and five invisible worlds. A close study of big bang nucleosynthesis (BBN) baryon asymmetries cosmic microwave background (CMB) bounds galaxy dynamics together with the Standard Model assumptions help us to set a limit on the mass and width of the new gauge boson. Modification of the statistics underlying the kinetic energy distribution of particles during the BBN is also discussed. The changes in reaction rates during the BBN due to a departure from the Debye-Hueckel electron screening model is also investigated.

C. A. Bertulani; T. Frederico; J. Fuqua; M. S. Hussein; O. Oliveira; W. de Paula

2012-01-01T23:59:59.000Z

126

Architecture, implementation and parallelization of the software to search for periodic gravitational wave signals  

E-Print Network (OSTI)

The parallelization, design and scalability of the \\sky code to search for periodic gravitational waves from rotating neutron stars is discussed. The code is based on an efficient implementation of the F-statistic using the Fast Fourier Transform algorithm. To perform an analysis of data from the advanced LIGO and Virgo gravitational wave detectors' network, which will start operating in 2015, hundreds of millions of CPU hours will be required - the code utilizing the potential of massively parallel supercomputers is therefore mandatory. We have parallelized the code using the Message Passing Interface standard, implemented a mechanism for combining the searches at different sky-positions and frequency bands into one extremely scalable program. The parallel I/O interface is used to escape bottlenecks, when writing the generated data into file system. This allowed to develop a highly scalable computation code, which would enable the data analysis at large scales on acceptable time scales. Benchmarking of the code on a Cray XE6 system was performed to show efficiency of our parallelization concept and to demonstrate scaling up to 50 thousand cores in parallel.

Gevorg Poghosyan; Sanchit Matta; Achim Streit; Micha? Bejger; Andrzej Królak

2014-10-14T23:59:59.000Z

127

SWAP: PARALLELIZATION THROUGH ALGORITHM SUBSTITUTION  

E-Print Network (OSTI)

://code.google.com/p/ thrust). There is a vast set of tasks that pro- grammers want to perform, and few of the algorithms: PARALLELIZATION THROUGH ALGORITHM SUBSTITUTION ................................................................................................................................................................................................................... BY EXPLICITLY INDICATING WHICH ALGORITHMS THEY USE AND ENCAPSULATING THESE ALGORITHMS WITHIN SOFTWARE COMPONENTS

Eeckhout, Lieven

128

Implicit Parallelism Alden H. Wright  

E-Print Network (OSTI)

Implicit Parallelism Alden H. Wright , Michael D. Vose ¡ , and Jonathan E. Rowe ¢ £ Dept. of Computer Science, University of Montana, Missoula, Montana 59812, USA wright@cs.umt.edu¤ Computer Science family of schemata. [Vose and Wright, 2001] showed that each schema corresponds to a vector in pop

Rowe, Jon

129

Modeling problem solving in Massive Open Online Courses  

E-Print Network (OSTI)

.Massive Open Online Courses (MOOC) have presented a completely new style of learning and teaching that also brings us a massive amount of student behavioral data. Some of this data is exclusive to the MOOC environment. ...

Han, Fang, M. Eng. Massachusetts Institute of Technology

2014-01-01T23:59:59.000Z

130

Parallel simulation of the Ising model  

Science Journals Connector (OSTI)

Methods for parallelizing Ising model simulations are presented. A parallel single-spin Metropolis algorithm [J. Chem. Phys. 21, 1087 (1953)] has been implemented with a speedup of 27 on 50 processors of the KSR-1 parallel computer. A parallel Swendsen-Wang algorithm [Phys. Rev. Lett. 58, 86 (1987)] obtains a speedup of 3.2 on nine processors of the same computer. Both of these simulations were carried out by 200×200 lattices. The parallel local cluster algorithm [Phys. Rev. Lett. 71, 2070 (1993)] has been implemented with an almost linear speedup. We also discuss ongoing research using the parallel local cluster algorithm.

G. T. Barkema and T. MacFarland

1994-08-01T23:59:59.000Z

131

A High-Performance Hybrid Computing Approach to Massive Contingency Analysis in the Power Grid  

SciTech Connect

Operating the electrical power grid to prevent power black-outs is a complex task. An important aspect of this is contingency analysis, which involves understanding and mitigating potential failures in power grid elements such as transmission lines. When taking into account the potential for multiple simultaneous failures (known as the N-x contingency problem), contingency analysis becomes a massively computational task. In this paper we describe a novel hybrid computational approach to contingency analysis. This approach exploits the unique graph processing performance of the Cray XMT in conjunction with a conventional massively parallel compute cluster to identify likely simultaneous failures that could cause widespread cascading power failures that have massive economic and social impact on society. The approach has the potential to provide the first practical and scalable solution to the N-x contingency problem. When deployed in power grid operations, it will increase the grid operator’s ability to deal effectively with outages and failures with power grid components while preserving stable and safe operation of the grid. The paper describes the architecture of our solution and presents preliminary performance results that validate the efficacy of our approach.

Gorton, Ian; Huang, Zhenyu; Chen, Yousu; Kalahar, Benson K.; Jin, Shuangshuang; Chavarría-Miranda, Daniel; Baxter, Douglas J.; Feo, John T.

2009-12-01T23:59:59.000Z

132

Massive Nonplanar Two-Loop Maximal Unitarity  

E-Print Network (OSTI)

We explore maximal unitarity for nonplanar two-loop integrals with up to four massive external legs. In this framework, the amplitude is reduced to a basis of master integrals whose coefficients are extracted from maximal cuts. The hepta-cut of the nonplanar double box defines a nodal algebraic curve associated with a multiply pinched genus-3 Riemann surface. All possible configurations of external masses are covered by two distinct topological pictures in which the curve decomposes into either six or eight Riemann spheres. The procedure relies on consistency equations based on vanishing of integrals of total derivatives and Levi-Civita contractions. Our analysis indicates that these constraints are governed by the global structure of the maximal cut. Lastly, we present an algorithm for computing generalized cuts of massive integrals with higher powers of propagators based on the Bezoutian matrix method.

Mads Sogaard; Yang Zhang

2014-06-19T23:59:59.000Z

133

More on massive 3D gravity  

Science Journals Connector (OSTI)

We explore the space of static solutions of the recently discovered three-dimensional “new massive gravity” (NMG), allowing for either sign of the Einstein-Hilbert term and a cosmological term parametrized by a dimensionless constant ?. For ?=-1 we find black hole solutions asymptotic (but not isometric) to the unique (anti) de Sitter [(A)dS] vacuum, including extremal black holes that interpolate between this vacuum and (A)dS2×S1. We also investigate unitarity of linearized NMG in (A)dS vacua. We find unitary theories for some dS vacua, but (bulk) unitarity in AdS implies negative central charge of the dual conformal field theories (CFT), except for ?=3 where the central charge vanishes and the bulk gravitons are replaced by “massive photons.” A similar phenomenon is found in the massless limit of NMG, for which the linearized equations become equivalent to Maxwell’s equations.

Eric A. Bergshoeff; Olaf Hohm; Paul K. Townsend

2009-06-26T23:59:59.000Z

134

Sudden singularities survive massive quantum particle production  

Science Journals Connector (OSTI)

We solve the Klein-Gordon equation for a massive, nonminimally coupled scalar field, with a conformal coupling, undergoing cosmological evolution from a radiation-dominated phase to a future sudden singularity. We show that, after regularization, the energy of the created particles is zero and the backreaction from quantum effects does not change the evolution of the Universe near the future singularity and cannot prevent the finite-time sudden singularity.

John D. Barrow; Antônio B. Batista; Júlio C. Fabris; Mahouton J. S. Houndjo; Giuseppe Dito

2011-12-23T23:59:59.000Z

135

Hyper-Systolic Parallel Computing  

E-Print Network (OSTI)

A new class of parallel algorithms is introduced that can achieve a complexity of O(n^3/2) with respect to the interprocessor communication, in the exact computation of systems with pairwise mutual interactions of all elements. Hitherto, conventional methods exhibit a communicational complexity of O(n^2). The amount of computation operations is not altered for the new algorithm which can be formulated as a kind of h-range problem, known from the mathematical field of Additive Number Theory. We will demonstrate the reduction in communicational expense by comparing the standard-systolic algorithm and the new algorithm on the connection machine CM5 and the CRAY T3D. The parallel method can be useful in various scientific and engineering fields like exact n-body dynamics with long range forces, polymer chains, protein folding or signal processing.

Th. Lippert; A. Seyfried; A. Bode; K. Schilling

1995-07-25T23:59:59.000Z

136

A Parallel Quantum Computer Simulator  

E-Print Network (OSTI)

A Quantum Computer is a new type of computer which can efficiently solve complex problems such as prime factorization. A quantum computer threatens the security of public key encryption systems because these systems rely on the fact that prime factorization is computationally difficult. Errors limit the effectiveness of quantum computers. Because of the exponential nature of quantum com puters, simulating the effect of errors on them requires a vast amount of processing and memory resources. In this paper we describe a parallel simulator which accesses the feasibility of quantum computers. We also derive and validate an analytical model of execution time for the simulator, which shows that parallel quantum computer simulation is very scalable.

Kevin M. Obenland; Alvin M. Despain

1998-04-16T23:59:59.000Z

137

A Novel Application of Parallel Betweenness Centrality to Power Grid Contingency Analysis  

SciTech Connect

In Energy Management Systems, contingency analysis is commonly performed for identifying and mitigating potentially harmful power grid component failures. The exponentially increasing combinatorial number of failure modes imposes a significant computational burden for massive contingency analysis. It is critical to select a limited set of high-impact contingency cases within the constraint of computing power and time requirements to make it possible for real-time power system vulnerability assessment. In this paper, we present a novel application of parallel betweenness centrality to power grid contingency selection. We cross-validate the proposed method using the model and data of the western US power grid, and implement it on a Cray XMT system - a massively multithreaded architecture - leveraging its advantages for parallel execution of irregular algorithms, such as graph analysis. We achieve a speedup of 55 times (on 64 processors) compared against the single-processor version of the same code running on the Cray XMT. We also compare an OpenMP-based version of the same code running on an HP Superdome shared-memory machine. The performance of the Cray XMT code shows better scalability and resource utilization, and shorter execution time for large-scale power grids. This proposed approach has been evaluated in PNNL’s Electricity Infrastructure Operations Center (EIOC). It is expected to provide a quick and efficient solution to massive contingency selection problems to help power grid operators to identify and mitigate potential widespread cascading power grid failures in real time.

Jin, Shuangshuang; Huang, Zhenyu; Chen, Yousu; Chavarría-Miranda, Daniel; Feo, John T.; Wong, Pak C.

2010-04-19T23:59:59.000Z

138

A parallel programming environment on grid  

Science Journals Connector (OSTI)

Computational grids are environment that provides the ability to exploit diverse, geographically distributed resources. Bulk Synchronous Parallel (BSP) model is a widely used parallel programming model. With rapid development of grid technologies, users ...

Weiqin Tong; Jingbo Ding; Lizhi Cai

2003-06-01T23:59:59.000Z

139

5 - MATLAB and Parallel Computing Toolbox  

Science Journals Connector (OSTI)

MATLAB provides useful tools for parallel processing from the Parallel Computing Toolbox. The toolbox provides diverse methods for parallel processing, such as multiple computers working via a network, several cores in multicore machines, and cluster computing as well as GPU parallel processing. Within the scope of this book, we focus more on the GPU part of the Parallel Computing Toolbox. One of the good things in the toolbox is that we can take advantage of \\{GPUs\\} without explicit CUDA or c-mex programming. However, this comes with a heavy price tag for us to install the Parallel Computing Toolbox. This chapter discusses GPU processing for built-in and non-built-in MATLAB functions, parallel task processing, parallel data processing, and the direct use of the CUDA file without c-mex.

Jung W. Suh; Youngmin Kim

2014-01-01T23:59:59.000Z

140

On-the-fly pipeline parallelism  

E-Print Network (OSTI)

Pipeline parallelism organizes a parallel program as a linear sequence of s stages. Each stage processes elements of a data stream, passing each processed data element to the next stage, and then taking on a new element ...

Lee, I-Ting Angelina

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


141

A Parallel Geometric Multifrontal Solver Using Hierarchically ...  

E-Print Network (OSTI)

In particular, we demonstrate how to manage two layers of tree parallelism that integrates ... allelism within the outer multifrontal tree parallelism, and how the rank properties behave and benefit the ...... Ph.D. Dissertation. Institut National ...

2014-07-17T23:59:59.000Z

142

Middle Path Coarse Grain Parallelization  

E-Print Network (OSTI)

Backend OpenMP Fortran OpenMP Backend MPI Fortran MPI Backend ½ �� � BPA RB SB Program Near fine grain layer 3rd layer Near fine grain parallelism in loop body BPA RB SB BPA RB SB BPA RB SB BPA RB SB BPA RB SB BPA RB SB ¾ ¾º½º½ � � Á � � � ¾ Data Dependency Extended Contorol Dependency Conditional Branch

Kasahara, Hironori

143

Alexandru Iosup Parallel and Distributed Systems Group  

E-Print Network (OSTI)

Online Games: High Performance Computing and High Quality Time 1 Massivizing Social Games: High,000,000 active players Massivizing Social Games: High Performance Computing and High Quality Time ­ A. Iosup 3 Games: High Performance Computing and High Quality Time ­ A. Iosup 4 Sources: MMOGChart, own research

Iosup, Alexandru

144

Kant and Parallel Lines Jeremy Heis  

E-Print Network (OSTI)

Kant and Parallel Lines Jeremy Heis University of California, Irvine HOPOS 2010 #12;Kant. #12;Two interesting issues 1. Was Kant aware of the problems posed to geometry by parallel lines? Did to geometry by parallel lines? Did he reflect on these problems? 2. Did these two "Euclidean" features of Kant

Barrett, Jeffrey A.

145

NWChem: scalable parallel computational chemistry  

SciTech Connect

NWChem is a general purpose computational chemistry code specifically designed to run on distributed memory parallel computers. The core functionality of the code focuses on molecular dynamics, Hartree-Fock and density functional theory methods for both plane-wave basis sets as well as Gaussian basis sets, tensor contraction engine based coupled cluster capabilities and combined quantum mechanics/molecular mechanics descriptions. It was realized from the beginning that scalable implementations of these methods required a programming paradigm inherently different from what message passing approaches could offer. In response a global address space library, the Global Array Toolkit, was developed. The programming model it offers is based on using predominantly one-sided communication. This model underpins most of the functionality in NWChem and the power of it is exemplified by the fact that the code scales to tens of thousands of processors. In this paper the core capabilities of NWChem are described as well as their implementation to achieve an efficient computational chemistry code with high parallel scalability. NWChem is a modern, open source, computational chemistry code1 specifically designed for large scale parallel applications2. To meet the challenges of developing efficient, scalable and portable programs of this nature a particular code design was adopted. This code design involved two main features. First of all, the code is build up in a modular fashion so that a large variety of functionality can be integrated easily. Secondly, to facilitate writing complex parallel algorithms the Global Array toolkit was developed. This toolkit allows one to write parallel applications in a shared memory like approach, but offers additional mechanisms to exploit data locality to lower communication overheads. This framework has proven to be very successful in computational chemistry but is applicable to any engineering domain. Within the context created by the features above NWChem has grown into a general purpose computational chemistry code that supports a wide variety of energy expressions and capabilities to calculate properties based there upon. The main energy expressions are classical mechanics force fields, Hartree-Fock and DFT both for finite systems and condensed phase systems, coupled cluster, as well as QM/MM. For most energy expressions single point calculations, geometry optimizations, excited states, and other properties are available. Below we briefly discuss each of the main energy expressions and the critical points involved in scalable implementations thereof.

van Dam, Hubertus JJ; De Jong, Wibe A.; Bylaska, Eric J.; Govind, Niranjan; Kowalski, Karol; Straatsma, TP; Valiev, Marat

2011-11-01T23:59:59.000Z

146

Supporting data intensive applications with medium grained parallelism. Progress report, July 1, 1991--February 28, 1992  

SciTech Connect

ADAMS is an ambitious effort to provide new database access paradigms for the kinds of scientific applications that require massively parallel access to very large data sets in order to be effective. Many of the Grand Challenge Problems fall into this category, as well as those kinds of scientific research which depend on widely distributed shared sets of disparate data. The essence of the ADAMS approach is to view data purely in functional terms, rather than the more traditional structural view in which multiple data items are aggregated into records or tuples of flat files. Further, ADAMS has been implemented as an embedded interface so that scientists can develop applications in the host programming language of their choice, often Fortran, Pascal, or C, and still access shared data generated in other environments. The syntax and semantics of ADAMS is essentially complete. The functional nature of the ADAMS data interface paradigm simplifies its implementation in a distributed environment, e.g., the Mentat run-time system, because one must only distribute functional servers, not pieces of data structures. However, this only opens up the possibility of effective parallel database processing; to realize this potential far more work must be done in the areas of data dependence, intra-statement parallelism, parallel query optimization, and maintaining consistency and reliability in concurrent systems. Discovering how to make effective parallel data access an actually in real scientific applications is the point of this research.

Pfaltz, J.L.; French, J.C.; Grimshaw, A.S.; Son, S.H.

1992-04-01T23:59:59.000Z

147

Development of Advanced Massive Heterogeneous Sensor Networks  

NLE Websites -- All DOE Office Websites (Extended Search)

Advanced Massive Heterogeneous Sensor Networks Research Team * Doug McCorkle * Kris Bryden * Mark Bryden Ames Laboratory U of Maryland * Ashwani Gupta * Miao Yu Power Plant Challenges * Conflicting goals of reliable low cost energy and climate change mitigation * Large investment in current infrastructure * Little implementation of information technologies Sensors ... * will be "free" * will be small (lick 'n stick) * will be smart * will be ubiquitous Low cost improvements in sensing for control and condition monitoring can result in big improvements in cost and carbon emissions * "... develop the understandings, algorithms, and control strategies needed to utilize large-scale, high- density sensor networks in advanced power plants." * Develop techniques for the

148

Casimir Effect of Scalar Massive Field  

E-Print Network (OSTI)

The energy momentum tensor is used to introduce the Casimir force of the massive scalar field acting on a nonpenetrating surface. This expression can be used to evaluate the vacuum force by employing the appropriate field operators. To simplify our formalism we also relates the vacuum force expression to the imaginary part of the Green function via the fluctuation dissipation theorem and Kubo formula. This allows one to evaluate the vacuum force without resorting to the process of field quantization. These two approaches are used to calculate the attractive force between two nonpenetrating plates. Special attention is paid to the generalization of the formalism to D + 1 space-time dimensions.

Sonia Mobassem

2014-03-03T23:59:59.000Z

149

The future of massive variability searches  

E-Print Network (OSTI)

This is a personal review of various issues related to massive photometric and astrometric searches. A complete inventory of variable stars down to almost any magnitude limit will improve our understanding of the stellar evolution and the galactic structure. A search for detached eclipsing binaries will improve the distance scale, the value of the Hubble constant, and the age of the oldest stars. A search for supernovae will help the determination of cosmological parameters Omega and Lambda. A search for microlensing events will provide insight into the stellar mass function, dark matter, and may lead to a discovery of earth-mass planets.

Paczynski, B

1996-01-01T23:59:59.000Z

150

Transport coefficients of a massive pion gas  

E-Print Network (OSTI)

We review or main results concerning the transport coefficients of a light meson gas, in particular we focus on the case of a massive pion gas. Leading order results according to the chiral power-counting are presented for the DC electrical conductivity, thermal conductivity, shear viscosity, and bulk viscosity. We also comment on the possible correlation between the bulk viscosity and the trace anomaly in QCD, as well as the relation between unitarity and a minimum of the quotient $\\eta/s$ near the phase transition.

D. Fernandez-Fraile; A. Gomez Nicola

2009-12-20T23:59:59.000Z

151

Investigations in massive 3D gravity  

SciTech Connect

Some interesting gravitational properties of the Bergshoeff-Hohm-Townsend model (massive 3D gravity), such as the presence of a short-range gravitational force in the nonrelativistic limit and the existence of an impact-parameter-dependent gravitational deflection angle, are studied. Interestingly enough, these phenomena have no counterpart in the usual Einstein 3D gravity. In order to better understand the two aforementioned gravitational properties, they are also analyzed in the framework of 3D higher-derivative gravity with the Einstein-Hilbert term with the 'wrong sign'.

Accioly, Antonio [Laboratorio de Fisica Experimental (LAFEX), Centro Brasileiro de Pesquisas Fisicas (CBPF), Rua Dr. Xavier Sigaud 150, Urca, 22290-180, Rio de Janeiro, RJ (Brazil); Instituto de Fisica Teorica (IFT), Sao Paulo State University (UNESP), Rua Dr. Bento Teobaldo Ferraz 271, Bloco II-Barra Funda, 01140-070, Sao Paulo, SP (Brazil); Helayeel-Neto, Jose; Morais, Jefferson; Turcati, Rodrigo [Laboratorio de Fisica Experimental (LAFEX), Centro Brasileiro de Pesquisas Fisicas (CBPF), Rua Dr. Xavier Sigaud 150, Urca, 22290-180, Rio de Janeiro, RJ (Brazil); Scatena, Eslley [Instituto de Fisica Teorica (IFT), Sao Paulo State University (UNESP), Rua Dr. Bento Teobaldo Ferraz 271, Bloco II-Barra Funda, 01140-070, Sao Paulo, SP (Brazil)

2011-05-15T23:59:59.000Z

152

Xyce parallel electronic simulator design.  

SciTech Connect

This document is the Xyce Circuit Simulator developer guide. Xyce has been designed from the 'ground up' to be a SPICE-compatible, distributed memory parallel circuit simulator. While it is in many respects a research code, Xyce is intended to be a production simulator. As such, having software quality engineering (SQE) procedures in place to insure a high level of code quality and robustness are essential. Version control, issue tracking customer support, C++ style guildlines and the Xyce release process are all described. The Xyce Parallel Electronic Simulator has been under development at Sandia since 1999. Historically, Xyce has mostly been funded by ASC, the original focus of Xyce development has primarily been related to circuits for nuclear weapons. However, this has not been the only focus and it is expected that the project will diversify. Like many ASC projects, Xyce is a group development effort, which involves a number of researchers, engineers, scientists, mathmaticians and computer scientists. In addition to diversity of background, it is to be expected on long term projects for there to be a certain amount of staff turnover, as people move on to different projects. As a result, it is very important that the project maintain high software quality standards. The point of this document is to formally document a number of the software quality practices followed by the Xyce team in one place. Also, it is hoped that this document will be a good source of information for new developers.

Thornquist, Heidi K.; Rankin, Eric Lamont; Mei, Ting; Schiek, Richard Louis; Keiter, Eric Richard; Russo, Thomas V.

2010-09-01T23:59:59.000Z

153

Knowledge Discovery from Massive Healthcare Claims Data  

SciTech Connect

The role of big data in addressing the needs of the present healthcare system in US and rest of the world has been echoed by government, private, and academic sectors. There has been a growing emphasis to explore the promise of big data analytics in tapping the potential of the massive healthcare data emanating from private and government health insurance providers. While the domain implications of such collaboration are well known, this type of data has been explored to a limited extent in the data mining community. The objective of this paper is two fold: first, we introduce the emerging domain of big"healthcare claims data to the KDD community, and second, we describe the success and challenges that we encountered in analyzing this data using state of art analytics for massive data. Specically, we translate the problem of analyzing healthcare data into some of the most well-known analysis problems in the data mining community, social network analysis, text mining, and temporal analysis and higher order feature construction, and describe how advances within each of these areas can be leveraged to understand the domain of healthcare. Each case study illustrates a unique intersection of data mining and healthcare with a common objective of improving the cost-care ratio by mining for opportunities to improve healthcare operations and reducing hat seems to fall under fraud, waste,and abuse.

Chandola, Varun [ORNL] [ORNL; Sukumar, Sreenivas R [ORNL] [ORNL; Schryver, Jack C [ORNL] [ORNL

2013-01-01T23:59:59.000Z

154

Massive Stars: Their Birth Sites and Distribution  

E-Print Network (OSTI)

The stellar IMF has been found to be an invariant Salpeter power-law (alpha=2.35) above about 1 Msun, but at the same time a massive star typically has more than one companion. This constrains the possible formation scenarios of massive stars, but also implies that the true, binary-star corrected stellar IMF could be significantly steeper than Salpeter, alpha>2.7. A significant fraction of all OB stars are found relatively far from potential birth sites which is most probably a result of dynamical ejections from cores of binary-rich star clusters. Such cores form rapidly due to dynamical mass segregation, or they are primordial. Probably all OB stars thus form in stellar clusters together with low-mass stars, and they have a rather devastating effect on the embedded cluster by rapidly driving out the remaining gas leaving expanding OB associations and bound star clusters. The distributed population of OB stars has a measured IMF with alpha about 4, which however, does not necessarily constitute a different physical mode for isolated star formation. A steep field-star IMF is obtained naturally because stars form in clusters which are distributed according to a power-law cluster mass function.

Pavel Kroupa

2003-09-22T23:59:59.000Z

155

Precursors of UCHII regions & the evolution of massive outflows  

E-Print Network (OSTI)

Since this contributions was meant to cover two subjects which are both in the field of massive star formation but which in its details can be discussed separately, this paper is divided in two sections. First, we present characteristics of precursors of UCH{\\sc ii} regions and their likely evolutionary properties. The second section discusses massive molecular outflows, their implications for high-mass star formation, and a possible evolutionary sequence for massive outflows.

H. Beuther; D. Shepherd

2005-02-10T23:59:59.000Z

156

Fermilab | Newsroom | Press Releases | January 13, 2014: Massive...  

NLE Websites -- All DOE Office Websites (Extended Search)

of the lab's attractions - including the massive electromagnet that was brought to Fermilab last summer. Highlights of the Open House include a series of performances by the...

157

Information hiding in parallel programs  

SciTech Connect

A fundamental principle in program design is to isolate difficult or changeable design decisions. Application of this principle to parallel programs requires identification of decisions that are difficult or subject to change, and the development of techniques for hiding these decisions. We experiment with three complex applications, and identify mapping, communication, and scheduling as areas in which decisions are particularly problematic. We develop computational abstractions that hide such decisions, and show that these abstractions can be used to develop elegant solutions to programming problems. In particular, they allow us to encode common structures, such as transforms, reductions, and meshes, as software cells and templates that can reused in different applications. An important characteristic of these structures is that they do not incorporate mapping, communication, or scheduling decisions: these aspects of the design are specified separately, when composing existing structures to form applications. This separation of concerns allows the same cells and templates to be reused in different contexts.

Foster, I.

1992-01-30T23:59:59.000Z

158

Time-parallel multiscale/multiphysics framework  

Science Journals Connector (OSTI)

We introduce the time-parallel compound wavelet matrix method (tpCWM) for modeling the temporal evolution of multiscale and multiphysics systems. The method couples time parallel (TP) and CWM methods operating at different spatial and temporal scales. ... Keywords: 02.00.00, 02.10.Jf, 05.10.-a, 46.15.-x, 47.70.Fw, Parallel-in-time, Wavelet-based multiscaling

G. Frantziskonis; K. Muralidharan; P. Deymier; S. Simunovic; P. Nukala; S. Pannala

2009-11-01T23:59:59.000Z

159

Cost hierarchies for abstract parallel machines  

E-Print Network (OSTI)

O'Donnell,J.T. Rauber,T. Ruenger,G. 13th International Workshop on Languages and Compilers for Parallel Computing (LCPC 2000) LNCS, Springer

O'Donnell, J.T.

160

Parallel auto-correlative statistics with VTK.  

SciTech Connect

This report summarizes existing statistical engines in VTK and presents both the serial and parallel auto-correlative statistics engines. It is a sequel to [PT08, BPRT09b, PT09, BPT09, PT10] which studied the parallel descriptive, correlative, multi-correlative, principal component analysis, contingency, k-means, and order statistics engines. The ease of use of the new parallel auto-correlative statistics engine is illustrated by the means of C++ code snippets and algorithm verification is provided. This report justifies the design of the statistics engines with parallel scalability in mind, and provides scalability and speed-up analysis results for the autocorrelative statistics engine.

Pebay, Philippe Pierre [Kitware, France; Bennett, Janine Camille

2013-08-01T23:59:59.000Z

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


161

Infinitary parallelism without unbounded nondeterminism in CSP  

Science Journals Connector (OSTI)

The theory of CSP is extended to include an infinitary parallel ... this operator adds to the expressive power of CSP. A comparison of this operator with that...

K. Narayan Kumar; Paritosh K. Pandya

1993-01-01T23:59:59.000Z

162

A scalable 2-D parallel sparse solver  

SciTech Connect

Scalability beyond a small number of processors, typically 32 or less, is known to be a problem for existing parallel general sparse (PGS) direct solvers. This paper presents a parallel general sparse PGS direct solver for general sparse linear systems on distributed memory machines. The algorithm is based on the well-known sequential sparse algorithm Y12M. To achieve efficient parallelization, a 2-D scattered decomposition of the sparse matrix is used. The proposed algorithm is more scalable than existing parallel sparse direct solvers. Its scalability is evaluated on a 256 processor nCUBE2s machine using Boeing/Harwell benchmark matrices.

Kothari, S.C.; Mitra, S. [Iowa State Univ., Ames, IA (United States)

1995-12-01T23:59:59.000Z

163

Optimize Parallel Pumping Systems | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Pumping Systems This tip sheet describes how to optimize the performance of multiple pumps operating continuously as part of a parallel pumping system. PUMPING SYSTEMS TIP SHEET...

164

Parallel Processing Letters World Scientific Publishing Company  

E-Print Network (OSTI)

Parallel Processing Letters © World Scientific Publishing Company THE OPERATIONS DASHBOARD essential operational services, it is imperative that grid administrators can troubleshoot the problems

Miller, Russ

165

Massive infrastructures are needed to support supercomputers  

NLE Websites -- All DOE Office Websites (Extended Search)

"Under the floor" of a supercomputer "Under the floor" of a supercomputer National Security Science magazine Latest Issue:April 2013 All Issues » submit Massive infrastructures are needed to support supercomputers Megawatts of power, millions of gallons of water, a football-field-size floor March 25, 2013 Tip of the computing iceberg The supercomputer room at Los Alamos is vast-essentially an acre. And this is just the tip of the iceberg. What's really amazing is what's under that floor. When a supercomputer covers 6,000 square feet of floor space, how do its guardians find and fix problems in only an hour? What's "under the floor" of a supercomputer? SUMMARY The infrastructure required to support a supercomputer includes megawatts of electricity to power it,millions of gallons of water to cool

166

Spectral Synthesis of Massive Stars in Clusters  

E-Print Network (OSTI)

Stellar clusters are thought to be the simplest stellar systems and the closest observational counterparts to theoretical models for single stellar populations. Progress in our understanding of the atmospheres and evolution of massive stars has led to generally reliable synthesis models. The future release of new evolution models with rotation, however, will require non-trivial updates to previously published synthesis models, in particular for all Wolf-Rayet and red supergiant related quantities. Cluster synthesis work is currently progressing from a purely stellar approach to a more comprehensive stellar+cluster perspective. The photometric evolution of stars and the dynamical evolution of clusters are delicately interwoven. Recent work attempts to combine these seemingly related fields.

Claus Leitherer

2006-08-31T23:59:59.000Z

167

Progress in the physics of massive neutrinos  

E-Print Network (OSTI)

The current status of the physics of massive neutrinos is reviewed with a forward-looking emphasis. The article begins with the general phenomenology of neutrino oscillations in vacuum and matter and documents the experimental evidence for oscillations of solar, reactor, atmospheric and accelerator neutrinos. Both active and sterile oscillation possibilities are considered. The impact of cosmology (BBN, CMB, leptogenesis) and astrophysics (supernovae, highest energy cosmic rays) on neutrino observables and vice versa, is evaluated. The predictions of grand unified, radiative and other models of neutrino mass are discussed. Ways of determining the unknown parameters of three-neutrino oscillations are assessed, taking into account eight-fold degeneracies in parameters that yield the same oscillation probabilities, as well as ways to determine the absolute neutrino mass scale (from beta-decay, neutrinoless double-beta decay, large scale structure and Z-bursts). Critical unknowns at present are the amplitude of \

V. Barger; D. Marfatia; K. Whisnant

2003-09-16T23:59:59.000Z

168

Cosmological evolutions of F(R) nonlinear massive gravity  

Science Journals Connector (OSTI)

Recently a new extended nonlinear massive gravity model has been proposed which includes the F(R) modifications to the de Rham–Gabadadze–Tolley model. We follow the F(R) nonlinear massive gravity and study its implications on cosmological evolutions. We derive the critical points of the cosmic system and study the corresponding kinetics by performing the phase-plane analysis.

De-Jun Wu

2014-08-25T23:59:59.000Z

169

Graphene-enabled Wireless Communication for Massive Multicore Architectures  

E-Print Network (OSTI)

Graphene-enabled Wireless Communication for Massive Multicore Architectures Sergi Abadal, Eduard. This goal is feasible by using graphene-based planar antennas, which can radiate signals at the Terahertz, this is the first work that discusses the utilization of graphene-enabled wireless communication for massive

Cabellos-Aparicio, Albert

170

A MASSIVE PROTOSTAR FORMING BY ORDERED COLLAPSE OF A DENSE, MASSIVE CORE  

SciTech Connect

We present 30 and 40 {mu}m imaging of the massive protostar G35.20-0.74 with SOFIA-FORCAST. The high surface density of the natal core around the protostar leads to high extinction, even at these relatively long wavelengths, causing the observed flux to be dominated by that emerging from the near-facing outflow cavity. However, emission from the far-facing cavity is still clearly detected. We combine these results with fluxes from the near-infrared to mm to construct a spectral energy distribution (SED). For isotropic emission the bolometric luminosity would be 3.3 Multiplication-Sign 10{sup 4} L{sub Sun }. We perform radiative transfer modeling of a protostar forming by ordered, symmetric collapse from a massive core bounded by a clump with high-mass surface density, {Sigma}{sub cl}. To fit the SED requires protostellar masses {approx}20-34 M{sub Sun} depending on the outflow cavity opening angle (35 Degree-Sign -50 Degree-Sign ), and {Sigma}{sub cl} {approx} 0.4-1 g cm{sup -2}. After accounting for the foreground extinction and the flashlight effect, the true bolometric luminosity is {approx}(0.7-2.2) Multiplication-Sign 10{sup 5} L{sub Sun }. One of these models also has excellent agreement with the observed intensity profiles along the outflow axis at 10, 18, 31, and 37 {mu}m. Overall our results support a model of massive star formation involving the relatively ordered, symmetric collapse of a massive, dense core and the launching bipolar outflows that clear low-density cavities. Thus a unified model may apply for the formation of both low- and high-mass stars.

Zhang, Yichen; Tan, Jonathan C.; Telesco, Charles [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)] [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); De Buizer, James M.; Sandell, Goeran; Shuping, Ralph [SOFIA-USRA, NASA Ames Research Center, MS 232-12, Building N232, P.O. Box 1, Moffett Field, CA 94035 (United States)] [SOFIA-USRA, NASA Ames Research Center, MS 232-12, Building N232, P.O. Box 1, Moffett Field, CA 94035 (United States); Beltran, Maria T. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, Firenze I-50125 (Italy)] [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, Firenze I-50125 (Italy); Churchwell, Ed; Whitney, Barbara [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States)] [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); McKee, Christopher F. [Department of Astronomy and Astrophysics, University of California, Berkeley, CA 94720 (United States)] [Department of Astronomy and Astrophysics, University of California, Berkeley, CA 94720 (United States); Staff, Jan E., E-mail: yc.zhang@astro.ufl.edu [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States)

2013-04-10T23:59:59.000Z

171

An improved parallel hybrid bi-conjugate gradient method suitable for distributed parallel computing  

Science Journals Connector (OSTI)

An improved parallel hybrid bi-conjugate gradient method (IBiCGSTAB(2) method, in brief) for solving large sparse linear systems with nonsymmetric coefficient matrices is proposed for distributed parallel environments. The method reduces five global ... Keywords: Distributed parallel environments, Global communication, IBiCGSTAB(2) method, Krylov subspace method, Sparse nonsymmetric linear system

Tong-Xiang Gu; Xian-Yu Zuo; Xing-Ping Liu; Pei-Lu Li

2009-04-01T23:59:59.000Z

172

Hypervelocity binary stars: smoking gun of massive binary black holes  

E-Print Network (OSTI)

The hypervelocity stars recently found in the Galactic halo are expelled from the Galactic center through interactions between binary stars and the central massive black hole or between single stars and a hypothetical massive binary black hole. In this paper, we demonstrate that binary stars can be ejected out of the Galactic center with velocities up to 10^3 km/s, while preserving their integrity, through interactions with a massive binary black hole. Binary stars are unlikely to attain such high velocities via scattering by a single massive black hole or through any other mechanisms. Based on the above theoretical prediction, we propose a search for binary systems among the hypervelocity stars. Discovery of hypervelocity binary stars, even one, is a definitive evidence of the existence of a massive binary black hole in the Galactic center.

Youjun Lu; Qingjuan Yu; D. N. C. Lin

2007-07-12T23:59:59.000Z

173

Using Cycles and Scaling Parallel Algorithms  

E-Print Network (OSTI)

graph by finding a max­ imal set of edge­disjoint cycles. We give a parallel algorithm to find the first efficient parallel algorithm for finding an approximation to a min­ imum cycle cover. Our algorithm finds a cycle cover whose size is within a factor of O(1 + n log n m+n ) of the minimum sized

Yang, Junfeng

174

Parallel MATLAB: Single Program Multiple Data  

E-Print Network (OSTI)

Parallel MATLAB: Single Program Multiple Data John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 67 #12;MATLAB Parallel MATLAB sets up one special agent called the client. MATLAB sets up the requested number of workers, each

Crawford, T. Daniel

175

Parallel MATLAB: Single Program Multiple Data  

E-Print Network (OSTI)

Parallel MATLAB: Single Program Multiple Data John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 67 #12;Matlab Parallel ( 'myscript', 'Profile', ... 'ithaca_R2012a', 'matlabpool', 7 ) 5 / 67 #12;SPMD: The SPMD Environment Matlab

Crawford, T. Daniel

176

Parallel MATLAB: Single Program Multiple Data  

E-Print Network (OSTI)

Parallel MATLAB: Single Program Multiple Data John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 66 #12;MATLAB Parallel MATLAB sets up one special worker called the client. MATLAB sets up the requested number of workers, each

Crawford, T. Daniel

177

Batch Scheduling with Deadlines on Parallel Machines  

E-Print Network (OSTI)

Batch Scheduling with Deadlines on Parallel Machines Peter Brucker Mikhail Y. Kovalyov, Yakov M of scheduling G groups of jobs on m parallel machines is considered. Each group consists of several identical) and to schedule the batches on the machines. It is possible for different batches of the same group

Magdeburg, Universität

178

Abstract AndParallel Machines Nachum Dershowitz  

E-Print Network (OSTI)

Abstract And­Parallel Machines Nachum Dershowitz University of Illinois Urbana, IL 61801 U are introduced. The first of them, the And­ Parallel Turing Machine, can be viewed as a generalization of the deterministic Turing machine in which the infinite tape is replaced by an infinite tree­like tape on which

Dershowitz, Nachum

179

Architecture of the VPP500 parallel supercomputer  

Science Journals Connector (OSTI)

The VPP500 vector parallel processor is a highly parallel, distributed memory supercomputer that has a performance range of 6.4 to 355 gigaFLOPS and a main memory capacity from 1 to 222 gigabytes. The system scalably supports between 4 and 222 processors ...

Teruo Utsumi; Masayuki Ikeda; Moriyuki Takamura

1994-11-01T23:59:59.000Z

180

Randomized Parallel Algorithms in Optimization Stephen Wright  

E-Print Network (OSTI)

Randomized Parallel Algorithms in Optimization Stephen Wright University of Wisconsin-Madison July 2013 Wright (UW-Madison) Random Parallel Optimization July 2013 1 / 52 #12;Collaborators @ UW-Madison Victor Bittorf Ji Liu Ben Recht ( Berkeley) Chris R´e ( Stanford) Krishna Sridhar Wright (UW

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


181

Broadcasting a message in a parallel computer  

DOE Patents (OSTI)

Methods, systems, and products are disclosed for broadcasting a message in a parallel computer. The parallel computer includes a plurality of compute nodes connected together using a data communications network. The data communications network optimized for point to point data communications and is characterized by at least two dimensions. The compute nodes are organized into at least one operational group of compute nodes for collective parallel operations of the parallel computer. One compute node of the operational group assigned to be a logical root. Broadcasting a message in a parallel computer includes: establishing a Hamiltonian path along all of the compute nodes in at least one plane of the data communications network and in the operational group; and broadcasting, by the logical root to the remaining compute nodes, the logical root's message along the established Hamiltonian path.

Berg, Jeremy E. (Rochester, MN); Faraj, Ahmad A. (Rochester, MN)

2011-08-02T23:59:59.000Z

182

X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen  

E-Print Network (OSTI)

X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen/s)Velocity (km/s) #12;absorption emission emission occulted emission emission UV telescope side side front back #12;absorption emission emission occulted emission emission UV telescope side side front back #12;The

Cohen, David

183

CRBLASTER: A Parallel-Processing Computational Framework for Embarrassingly-Parallel Image-Analysis Algorithms  

E-Print Network (OSTI)

The development of parallel-processing image-analysis codes is generally a challenging task that requires complicated choreography of interprocessor communications. If, however, the image-analysis algorithm is embarrassingly parallel, then the development of a parallel-processing implementation of that algorithm can be a much easier task to accomplish because, by definition, there is little need for communication between the compute processes. I describe the design, implementation, and performance of a parallel-processing image-analysis application, called CRBLASTER, which does cosmic-ray rejection of CCD (charge-coupled device) images using the embarrassingly-parallel L.A.COSMIC algorithm. CRBLASTER is written in C using the high-performance computing industry standard Message Passing Interface (MPI) library. The code has been designed to be used by research scientists who are familiar with C as a parallel-processing computational framework that enables the easy development of parallel-processing image-analy...

Mighell, Kenneth John

2010-01-01T23:59:59.000Z

184

Characterising Vainshtein Solutions in Massive Gravity  

E-Print Network (OSTI)

We study static, spherically symmetric solutions in a recently proposed ghost-free model of non-linear massive gravity. We focus on a branch of solutions where the helicity-0 mode can be strongly coupled within certain radial regions, giving rise to the Vainshtein effect. We truncate the analysis to scales below the gravitational Compton wavelength, and consider the weak field limit for the gravitational potentials, while keeping all non-linearities of the helicity-0 mode. We determine analytically the number and properties of local solutions which exist asymptotically on large scales, and of local (inner) solutions which exist on small scales. We find two kinds of asymptotic solutions, one of which is asymptotically flat, while the other one is not, and also two types of inner solutions, one of which displays the Vainshtein mechanism, while the other exhibits a self-shielding behaviour of the gravitational field. We analyse in detail in which cases the solutions match in an intermediate region. The asymptotically flat solutions connect only to inner configurations displaying the Vainshtein mechanism, while the non asymptotically flat solutions can connect with both kinds of inner solutions. We show furthermore that there are some regions in the parameter space where global solutions do not exist, and characterise precisely in which regions of the phase space the Vainshtein mechanism takes place.

Fulvio Sbisa'; Gustavo Niz; Kazuya Koyama; Gianmassimo Tasinato

2014-06-17T23:59:59.000Z

185

MACHO (MAssive Compact Halo Objects) Data  

DOE Data Explorer (OSTI)

The primary aim of the MACHO Project is to test the hypothesis that a significant fraction of the dark matter in the halo of the Milky Way is made up of objects like brown dwarfs or planets: these objects have come to be known as MACHOs, for MAssive Compact Halo Objects. The signature of these objects is the occasional amplification of the light from extragalactic stars by the gravitational lens effect. The amplification can be large, but events are extremely rare: it is necessary to monitor photometrically several million stars for a period of years in order to obtain a useful detection rate. For this purpose MACHO has a two channel system that employs eight CCDs, mounted on the 50 inch telescope at Mt. Stromlo. The high data rate (several GBytes per night) is accommodated by custom electronics and on-line data reduction. The Project has taken more than 27,000 images with this system since June 1992. Analysis of a subset of these data has yielded databases containing light curves in two colors for 8 million stars in the LMC and 10 million in the bulge of the Milky Way. A search for microlensing has turned up four candidates toward the Large Magellanic Cloud and 45 toward the Galactic Bulge. The web page for data provides links to MACHO Project data portals and various specialized interfaces for viewing or searching the data. (Specialized Interface)

186

Reynolds and Mach Number Scaling in Stationary Compressible Turbulence Using Massively Parallel High Resolution Direct Numerical Simulations  

E-Print Network (OSTI)

. . . . . . . . . . . . . . . . . . . 64 III.C.1. Dilatational Dissipation . . . . . . . . . . . . . 68 III.D. Summary . . . . . . . . . . . . . . . . . . . . . . . . . 71 IV ROLE OF THERMODYNAMIC AND DILATATIONAL FLUC- TUATIONS IN STATIONARY COMPRESSIBLE TURBULENCE . 73 IV.A. Pressure... Statistics . . . . . . . . . . . . . . . . . . . . 73 IV.A.1. Solenoidal and Dilatational Pressure Scaling . . 73 IV.A.2. p.d.f. of Pressure . . . . . . . . . . . . . . . . . 77 IV.A.3. p.d.f. of Enstrophy . . . . . . . . . . . . . . . . 80 IV.A.4. p...

Jagannathan, Shriram

2014-07-24T23:59:59.000Z

187

PUBLISHED ONLINE: 25 APRIL 2010 | DOI: 10.1038/NPHYS1636 Massively parallel computing on an organic  

E-Print Network (OSTI)

of the human brain fire at around just 103 times per second, the simultaneous collective action of millions for a new problem or even select a suitable circuit from a few available ones to evolve its hardware1 . However, once the logical path to solve a problem is determined, current is passed through a circuit

Loss, Daniel

188

MASSIVELY PARALLEL FULLY COUPLED IMPLICIT MODELING OF COUPLED THERMAL-HYDROLOGICAL-MECHANICAL PROCESSES FOR ENHANCED GEOTHERMAL SYSTEM RESERVOIRS  

SciTech Connect

Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing) to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid system and our ability to reliably predict how reservoirs behave under stimulation and production. In order to increase our understanding of how reservoirs behave under these conditions, we have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a continuum multiphase flow and heat transport model. In DEM simulations, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external load is applied. DEM models have been applied to a very wide range of fracturing processes from the molecular scale (where thermal fluctuations play an important role) to scales on the order of 1 km or greater. In this approach, the continuum flow and heat transport equations are solved on an underlying fixed finite element grid with evolving porosity and permeability for each grid cell that depends on the local structure of the discrete element network (such as DEM particle density). The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms and fractures. Such deformation/fracturing in turn changes the permeability, which again changes the evolution of fluid pressure, coupling the two phenomena. The intimate coupling between fracturing and fluid flow makes the meso-scale DEM simulations necessary, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed.

Robert Podgorney; Hai Huang; Derek Gaston

2010-02-01T23:59:59.000Z

189

Proc. of IEEE Int. Conf. on Robotics and Automation, San Diego, CA, May 1994. Sensorless Manipulation Using Massively Parallel  

E-Print Network (OSTI)

Proc. of IEEE Int. Conf. on Robotics and Automation, San Diego, CA, May 1994. Sensorless Robert Mihailovich Noel C. MacDonald Robotics & Vision Laboratory \\Lambda School of Electrical in the Robotics and Vi­ sion Laboratory at Cornell University. Support for our robotics research is provided

Richardson, David

190

Noninvasive prenatal diagnosis of fetal chromosomal aneuploidy by massively parallel genomic sequencing of DNA in maternal plasma  

Science Journals Connector (OSTI)

...1998 ) Quantitative analysis of fetal DNA in maternal plasma...epigenetic allelic ratio analysis in maternal plasma: theoretical...high-density picolitre reactors . Nature 437 : 376 – 380...Composition-sensitive analysis of the human genome for...marker that improves the reliability of noninvasive...

Rossa W. K. Chiu; K. C. Allen Chan; Yuan Gao; Virginia Y. M. Lau; Wenli Zheng; Tak Y. Leung; Chris H. F. Foo; Bin Xie; Nancy B. Y. Tsui; Fiona M. F. Lun; Benny C. Y. Zee; Tze K. Lau; Charles R. Cantor; Y. M. Dennis Lo

2008-01-01T23:59:59.000Z

191

HPPC EUROPAR August 31 Naples | Computer Architecture Group, Dept. Computer Science | 1 The Massively Parallel Computing Model GCA  

E-Print Network (OSTI)

HPPC ­ EUROPAR August 31 Naples | Computer Architecture Group, Dept. Computer Science | 1 Architecure Group #12;HPPC ­ EUROPAR August 31 Ischia | Computer Architecture Group, Dept. Computer Science Architecture Group, Dept. Computer Science | 3 Outline PART I: Global Cellular Automata (GCA) Cellular

Hoffmann, Rolf

192

Scalable mpNoC for Massively Parallel Systems Design and Implementation M. Baklouti,a,b  

E-Print Network (OSTI)

, Villeneuve d'ascq, France INRIA Lille Nord Europe, F-59650, Villeneuve d'ascq, France UMR 8022, CNRS, F-59650 Stream Multi- ple Data Stream) architectures. This allows them to speed-up significantly execution times

Paris-Sud XI, Université de

193

Language constructs for modular parallel programs  

SciTech Connect

We describe programming language constructs that facilitate the application of modular design techniques in parallel programming. These constructs allow us to isolate resource management and processor scheduling decisions from the specification of individual modules, which can themselves encapsulate design decisions concerned with concurrence, communication, process mapping, and data distribution. This approach permits development of libraries of reusable parallel program components and the reuse of these components in different contexts. In particular, alternative mapping strategies can be explored without modifying other aspects of program logic. We describe how these constructs are incorporated in two practical parallel programming languages, PCN and Fortran M. Compilers have been developed for both languages, allowing experimentation in substantial applications.

Foster, I.

1996-03-01T23:59:59.000Z

194

Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications  

E-Print Network (OSTI)

Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications, Berkeley Spring 1998 #12; Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications Copyright © 1998 by Michael Cameron Williamson #12; 1 Abstract Synthesis of Parallel Hardware

195

Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications  

E-Print Network (OSTI)

Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications, Berkeley Spring 1998 #12;Synthesis of Parallel Hardware Implementations from Synchronous Dataflow Graph Specifications Copyright © 1998 by Michael Cameron Williamson #12;1 Abstract Synthesis of Parallel Hardware

196

Data partitioning and load balancing in parallel disk systems  

Science Journals Connector (OSTI)

...Parallel disk systems provide opportunities for exploiting I/O parallelism in two possible ways, namely via inter-request and intra-request parallelism. In this paper, we discuss the main issues in performance...

Peter Scheuermann; Gerhard Weikum; Peter Zabback

1998-02-01T23:59:59.000Z

197

Parallel VLSI Circuit Analysis and Optimization  

E-Print Network (OSTI)

CAD application addressed in this dissertation is the Simulation Program with Integrated Circuit Emphasis (SPICE) like circuit simulation. SPICE simulation is often regarded as the bottleneck of the design flow. Recently, parallel circuit simulation...

Ye, Xiaoji

2012-02-14T23:59:59.000Z

198

Provably Efficient Adaptive Scheduling for Parallel Jobs  

E-Print Network (OSTI)

Scheduling competing jobs on multiprocessors has always been an important issue for parallel and distributed systems. The challenge is to ensure global, system-wide efficiency while offering a level of fairness to user ...

He, Yuxiong

199

Competitive Parallel Disk Prefetching and Buffer Management  

E-Print Network (OSTI)

We provide a competitive analysis framework for online prefetching and buffer management algorithms in parallel I/O systems, using a read-once model of block references. This has widespread applicability to key I/O-bound ...

Barve, Rakesh; Kallahalla, Mahesh; Varman, Peter J.; Vitter, Jeffrey Scott

2000-01-01T23:59:59.000Z

200

Parallel programming with PCN. Revision 1  

SciTech Connect

PCN is a system for developing and executing parallel programs. It comprises a high-level programming language, tools for developing and debugging programs in this language, and interfaces to Fortran and C that allow the reuse of existing code in multilingual parallel programs. Programs developed using PCN are portable across many different workstations, networks, and parallel computers. This document provides all the information required to develop parallel programs with the PCN programming system. In includes both tutorial and reference material. It also presents the basic concepts that underly PCN, particularly where these are likely to be unfamiliar to the reader, and provides pointers to other documentation on the PCN language, programming techniques, and tools. PCN is in the public domain. The latest version of both the software and this manual can be obtained by anonymous FTP from Argonne National Laboratory in the directory pub/pcn at info.mcs.anl.gov (c.f. Appendix A).

Foster, I.; Tuecke, S.

1991-12-01T23:59:59.000Z

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


201

Massive Cement Pour into Hanford Site Nuclear Facility Underway: Recovery  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Massive Cement Pour into Hanford Site Nuclear Facility Underway: Massive Cement Pour into Hanford Site Nuclear Facility Underway: Recovery Act Funding Puts U Canyon in Home Stretch of Demolition Preparations Massive Cement Pour into Hanford Site Nuclear Facility Underway: Recovery Act Funding Puts U Canyon in Home Stretch of Demolition Preparations June 14, 2011 - 12:00pm Addthis Media Contacts Andre Armstrong, CH2M HILL Plateau Remediation Company (509) 376-6773 Andre_L_Armstrong@rl.gov Geoff Tyree, DOE (509) 376-4171 Geoffrey.Tyree@rl.doe.gov RICHLAND, Wash. - Hanford workers are pouring enough cement-like material to fill six Olympic-size wimming pools in one of the U.S. Department of Energy's (DOE) largest nuclear facilities at the Hanford Site in southeast Washington State to prepare the massive building for demolition.

202

Protecting Recovery Act Cleanup Site During Massive Wildfire | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Protecting Recovery Act Cleanup Site During Massive Wildfire Protecting Recovery Act Cleanup Site During Massive Wildfire Protecting Recovery Act Cleanup Site During Massive Wildfire Effective safety procedures in place at Los Alamos National Laboratory would have provided protections in the event that the raging Las Conchas fire had spread to the site of an American Recovery and Reinvestment Act project. "Our procedures not only placed the waste excavation site, Materials Disposal Area B (MDA-B), into a safe posture so it was well protected during the fire, but also allowed us to resume work quickly," said Project Director Al Chaloupka. Protecting Recovery Act Cleanup Site During Massive Wildfire More Documents & Publications Los Alamos Lab Completes Excavation of Waste Disposal Site Used in the 1940s

203

Topologically Massive Gravity and Ricci-Cotton Flow  

E-Print Network (OSTI)

We consider Topologically Massive Gravity (TMG), which is three dimensional general relativity with a cosmological constant and a gravitational Chern-Simons term. When the cosmological constant is negative the theory has two potential vacuum solutions: Anti-de Sitter space and Warped Anti-de Sitter space. The theory also contains a massive graviton state which renders these solutions unstable for certain values of the parameters and boundary conditions. We study the decay of these solutions due to the condensation of the massive graviton mode using Ricci-Cotton flow, which is the appropriate generalization of Ricci flow to TMG. When the Chern-Simons coupling is small the AdS solution flows to warped AdS by the condensation of the massive graviton mode. When the coupling is large the situation is reversed, and warped AdS flows to AdS. Minisuperspace models are constructed where these flows are studied explicitly.

Nima Lashkari; Alexander Maloney

2010-09-14T23:59:59.000Z

204

Topologically Massive Gravity and Ricci-Cotton Flow  

E-Print Network (OSTI)

We consider Topologically Massive Gravity (TMG), which is three dimensional general relativity with a cosmological constant and a gravitational Chern-Simons term. When the cosmological constant is negative the theory has two potential vacuum solutions: Anti-de Sitter space and Warped Anti-de Sitter space. The theory also contains a massive graviton state which renders these solutions unstable for certain values of the parameters and boundary conditions. We study the decay of these solutions due to the condensation of the massive graviton mode using Ricci-Cotton flow, which is the appropriate generalization of Ricci flow to TMG. When the Chern-Simons coupling is small the AdS solution flows to warped AdS by the condensation of the massive graviton mode. When the coupling is large the situation is reversed, and warped AdS flows to AdS. Minisuperspace models are constructed where these flows are studied explicitly.

Lashkari, Nima

2010-01-01T23:59:59.000Z

205

Double Diffusion in Enclosure Bounded by Massive and Volatilizing Walls  

E-Print Network (OSTI)

-10), are considered. Other governing parameters are maintained constant (Rayleigh number, Prandtl number, Lewis number and width ratio of massive wall to enclosure). The conjugate heat transfer of the thick wall and indoor airflow and the enhanced heat transfer...

Liu, D.; Tang, G.; Zhao, F.

2006-01-01T23:59:59.000Z

206

D0-D8-F1 in Massive IIA SUGRA  

E-Print Network (OSTI)

We present some new supersymmetric solutions of massive IIA supergravity involving D0-branes, a D8-brane and a string. For the bosonic fields we use a general ansatz with SO(8) symmetry.

M. Massar; J. Troost

1999-01-26T23:59:59.000Z

207

An alternative derivation of the Minimal massive 3D gravity  

E-Print Network (OSTI)

By using the algebra of exterior forms and the first order formalism with constraints, an alternative derivation of the field equations for the Minimal massive 3D gravity model is presented.

Ahmet Baykal

2014-08-22T23:59:59.000Z

208

Massive Cement Pour into Hanford Site Nuclear Facility Underway: Recovery  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Massive Cement Pour into Hanford Site Nuclear Facility Underway: Massive Cement Pour into Hanford Site Nuclear Facility Underway: Recovery Act Funding Puts U Canyon in Home Stretch of Demolition Preparations Massive Cement Pour into Hanford Site Nuclear Facility Underway: Recovery Act Funding Puts U Canyon in Home Stretch of Demolition Preparations June 14, 2011 - 12:00pm Addthis Media Contacts Andre Armstrong, CH2M HILL Plateau Remediation Company (509) 376-6773 Andre_L_Armstrong@rl.gov Geoff Tyree, DOE (509) 376-4171 Geoffrey.Tyree@rl.doe.gov RICHLAND, Wash. - Hanford workers are pouring enough cement-like material to fill six Olympic-size wimming pools in one of the U.S. Department of Energy's (DOE) largest nuclear facilities at the Hanford Site in southeast Washington State to prepare the massive building for demolition.

209

Efficient Flow Computation on Massive Grid Terrain Datasets  

E-Print Network (OSTI)

As detailed terrain data becomes available, GIS terrain applications target larger geographic areas at ner resolutions. Processing the massive data involved in such applications presents signi cant challenges to GIS ...

Arge, Lars; Chase, Jeffry S.; Haplin, Patrick; Toma, Laura; Vitter, Jeffrey Scott; Urban, Dean; Wickremesinghe, Rajiv

2003-01-01T23:59:59.000Z

210

LDV Measurement of Confined Parallel Jet Mixing  

SciTech Connect

Laser Doppler Velocimetry (LDV) measurements were taken in a confinement, bounded by two parallel walls, into which issues a row of parallel jets. Two-component measurements were taken of two mean velocity components and three Reynolds stress components. As observed in isolated three dimensional wall bounded jets, the transverse diffusion of the jets is quite large. The data indicate that this rapid mixing process is due to strong secondary flows, transport of large inlet intensities and Reynolds stress anisotropy effects.

R.F. Kunz; S.W. D'Amico; P.F. Vassallo; M.A. Zaccaria

2001-01-31T23:59:59.000Z

211

The Manycore Revolution and Parallel Software Projects at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

forward, lowering the barrier to entry for parallel computing and making parallel machines more attractive as commercial products. Why it Matters: Although MPI is currently the...

212

Chassis Dynamometer Testing of Parallel and Series Diesel Hybrid...  

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

Chassis Dynamometer Testing of Parallel and Series Diesel Hybrid Buses Chassis Dynamometer Testing of Parallel and Series Diesel Hybrid Buses Emissions and fuel economy data were...

213

Analysis and design of cable-driven parallel kinematic mechanisms.  

E-Print Network (OSTI)

??This thesis concerns the analysis and design of cable-driven parallel mechanisms (CDPM). Structurally, a CDPM is formed by replacing the supporting legs of a parallel… (more)

Pham, Cong Bang.

2008-01-01T23:59:59.000Z

214

Density Perturbations in the Universe from Massive Vector Fields  

SciTech Connect

I discuss the possibility of using a massive vector field to generate the density perturbation in the Universe. I find that a scale-invariant superhorizon spectrum of vector field perturbations is possible to generate during inflation. The associated curvature perturbation is imprinted onto the Universe following the curvaton scenario. The mechanism does not generate a long-range anisotropy because an oscillating massive vector field behaves as a pressureless isotropic fluid.

Dimopoulos, K. [Physics Department, Lancaster University, Lancaster LA1 4YB (United Kingdom)

2007-11-20T23:59:59.000Z

215

Honeywell/Capstone Parallel Stand-alone Tests Honeywell/Capstone Parallel Tests  

E-Print Network (OSTI)

Appendix H Honeywell/Capstone Parallel Stand-alone Tests 6/20/2001 #12;Honeywell/Capstone Parallel3Ã? (VAR) Honeywell power Capstone Derived Power Figure H-1: Ramp Up Load Bank Power and Start Grid and Shaft Speed #12;Honeywell/Capstone Parallel Tests 6/20/2001 -10,000 0 10,000 20,000 30,000 40,000 50

216

GRBs as Probes of Massive Stars Near and Far  

E-Print Network (OSTI)

Long-duration gamma-ray bursts are the manifestations of massive stellar death. Due to the immense energy release they are detectable from most of the observable universe. In this way they allow us to study the deaths of single (or binary) massive stars possibly throughout the full timespan massive stars have existed in the Universe. GRBs provide a means to infer information about the environments and typical galaxies in which massive stars are formed. Two main obstacles remain to be crossed before the full potential of GRBs as probes of massive stars can be harvested: i) we need to build more complete and well understood samples in order not to be fooled by biases, and ii) we need to understand to which extent GRBs may be intrinsically biased in the sense that they are only formed by a limited subset of massive stars defined by most likely a restricted metallicity interval. We describe the status of an ongoing effort to build a more complete sample of long-duration GRBs with measured redshifts. Already now we can conclude that the environments of GRB progenitors are very diverse with metallicities ranging from solar to a hundredth solar and extinction ranging from none to A_V>5 mag. We have also identified a sightline with significant escape of Lyman continuum photons and another with a clear 2175AA extinction bump.

J. Fynbo; D. Malesani

2008-11-24T23:59:59.000Z

217

Capture Formed Binaries via Encounters with Massive Protostars  

E-Print Network (OSTI)

Most massive stars are found in the center of dense clusters, and have a companion fraction much higher than their lower mass siblings; the massive stars of the Trapezium core in Orion have ~ 1.5 companions each. This high multiplicity could be a consequence of formation via a capture scenario, or it could be due to fragmentation of the cores that form the massive stars. During stellar formation circumstellar disks appear to be nearly ubiquitous. Their large radii compared to stellar sizes increase the interaction radius significantly, suggesting that disk interactions with neighboring stars could assist in capturing binary companions. This mechanism has been studied for stars of approximately solar mass and found to be inefficient. In this paper we present simulations of interactions between a 22 Msun star-disk system and less massive impactors, to study the disk-assisted capture formation of binaries in a regime suited to massive stars. The formation of binaries by capture is found to be much more efficient for massive capturers. We discuss the effects of a mass dependent velocity dispersion and mass segregation on the capture rates, and consider the long term survival of the resultant binaries in a dense cluster.

Nickolas Moeckel; John Bally

2006-10-20T23:59:59.000Z

218

A methodology for deriving parallel programs with a family of Abstract Parallel Machines  

E-Print Network (OSTI)

O'Donnell,J.T. Runger,G. Lecture Notes in Computer Science. Volume 1300. Euro-Par'97: Parallel Processing (Passau, Germany) pp 662-669 Springer

O'Donnell, J.T.

219

1996 InternationalConference on Parallel Processing PARALLEL IMPLEMENTATION OF CONE BEAM TOMOGRAPHY  

E-Print Network (OSTI)

projections us- ing computed tomography (CT) is the noninvasive measure of structure from external as follows: A. Weight projection data B. Convolve weighted projection data Pe*(u,v) = P&L, U) * h(u) C1996 InternationalConference on Parallel Processing PARALLEL IMPLEMENTATION OF CONE BEAM TOMOGRAPHY

Chaudhary, Vipin

220

Salvador de Bahia, 2008 1 Parallel Computing: General  

E-Print Network (OSTI)

Salvador de Bahia, 2008 1 Parallel Computing: General Perspective and Applications Domingo Giménez://dis.um.es/~domingo #12;Salvador de Bahia, 2008 2 Content General aspects of parallel computing Necessity of parallel Case study II: Meteorology #12;Salvador de Bahia, 2008 3 Parallel Computing Several processors working

Giménez, Domingo

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


221

Data communications in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Data communications in a parallel active messaging interface (`PAMI`) of a parallel computer composed of compute nodes that execute a parallel application, each compute node including application processors that execute the parallel application and at least one management processor dedicated to gathering information regarding data communications. The PAMI is composed of data communications endpoints, each endpoint composed of a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes and the endpoints coupled for data communications through the PAMI and through data communications resources. Embodiments function by gathering call site statistics describing data communications resulting from execution of data communications instructions and identifying in dependence upon the call cite statistics a data communications algorithm for use in executing a data communications instruction at a call site in the parallel application.

Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

2013-11-12T23:59:59.000Z

222

A PARALLEL EXTENSION OF THE UAL ENVIRONMENT.  

SciTech Connect

The deployment of the Unified Accelerator Library (UAL) environment on the parallel cluster is presented. The approach is based on the Message-Passing Interface (MPI) library and the Perl adapter that allows one to control and mix together the existing conventional UAL components with the new MPI-based parallel extensions. In the paper, we provide timing results and describe the application of the new environment to the SNS Ring complex beam dynamics studies, particularly, simulations of several physical effects, such as space charge, field errors, fringe fields, and others.

MALITSKY, N.; SHISHLO, A.

2001-06-18T23:59:59.000Z

223

Ball State building massive geothermal system | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Ball State building massive geothermal system Ball State building massive geothermal system Ball State building massive geothermal system March 19, 2010 - 5:47pm Addthis Workers drill boreholes for a geothermal heating and cooling system at Ball State University’s campus in Muncie, Ind. | Photo courtesy of Ball State University Workers drill boreholes for a geothermal heating and cooling system at Ball State University's campus in Muncie, Ind. | Photo courtesy of Ball State University Paul Lester Communications Specialist for the Office of Energy Efficiency and Renewable Energy Ball State University is building America's largest ground source district geothermal heating and cooling system. The new operation will save the school millions of dollars, slash greenhouse gases and create jobs. The project will also "expand how America will define the use of

224

Ball State building massive geothermal system | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Ball State building massive geothermal system Ball State building massive geothermal system Ball State building massive geothermal system March 19, 2010 - 5:47pm Addthis Workers drill boreholes for a geothermal heating and cooling system at Ball State University’s campus in Muncie, Ind. | Photo courtesy of Ball State University Workers drill boreholes for a geothermal heating and cooling system at Ball State University's campus in Muncie, Ind. | Photo courtesy of Ball State University Paul Lester Communications Specialist, Office of Energy Efficiency and Renewable Energy Ball State University is building America's largest ground source district geothermal heating and cooling system. The new operation will save the school millions of dollars, slash greenhouse gases and create jobs. The project will also "expand how America will define the use of

225

Massive Soil Cleanup Effort Concludes at Hanford - Recovery Act Funding  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Massive Soil Cleanup Effort Concludes at Hanford - Recovery Act Massive Soil Cleanup Effort Concludes at Hanford - Recovery Act Funding Pays for Safe Disposal of 20,000 Truckloads of Soil Massive Soil Cleanup Effort Concludes at Hanford - Recovery Act Funding Pays for Safe Disposal of 20,000 Truckloads of Soil August 11, 2011 - 12:00pm Addthis Media Contacts Andre Armstrong, CH2M HILL Andre_L_Armstrong@rl.gov 509-376-6773 Geoff Tyree, DOE Geoffrey.Tyree@rl.doe.gov 509-376-4171 RICHLAND, Wash. - U.S. Department of Energy contractor CH2M HILL Plateau Remediation Company removed nearly half a million tons of contaminated soil over the last two years using American Recovery and Reinvestment Act funding at the Hanford Site in southeast Washington State. Workers shipped more than 20,000 truckloads of contaminated soil excavated

226

Massive spin-2 particle from a rank-2 tensor  

Science Journals Connector (OSTI)

Here we obtain all possible second-order theories for a rank-2 tensor which describe a massive spin-2 particle. We start with a general second-order Lagrangian with ten real parameters. The absence of lower-spin modes and the existence of two local field redefinitions leads us to only one free parameter. The solutions are split into three one-parameter classes according to the local symmetries of the massless limit. In the class which contains the usual massive Fierz-Pauli theory, the subset of spin-1 massless symmetries is maximal. In another class where the subset of spin-0 symmetries is maximal, the massless theory is invariant under Weyl transformations and the mass term does not need to fit into the form of the Fierz-Pauli mass term. In the remaining third class neither the spin-1 nor the spin-0 symmetry is maximal and we have a new family of spin-2 massive theories.

D. Dalmazi

2013-06-19T23:59:59.000Z

227

Massive Stars in Colliding Wind Systems: the GLAST Perspective  

SciTech Connect

Colliding winds of massive stars in binary systems are considered as candidate sites of high-energy non-thermal photon emission. They are already among the suggested counterparts for a few individual unidentified EGRET sources, but may constitute a detectable source population for the GLAST observatory. The present work investigates such population study of massive colliding wind systems at high-energy gamma-rays. Based on the recent detailed model (Reimer et al. 2006) for non-thermal photon production in prime candidate systems, we unveil the expected characteristics of this source class in the observables accessible at LAT energies. Combining the broadband emission model with the presently cataloged distribution of such systems and their individual parameters allows us to conclude on the expected maximum number of LAT-detections among massive stars in colliding wind binary systems.

Reimer, Anita; Reimer, Olaf; /Stanford U., HEPL /KIPAC, Menlo Park

2011-11-29T23:59:59.000Z

228

Massive Black Hole Science with eLISA  

E-Print Network (OSTI)

The evolving Laser Interferometer Space Antenna (eLISA) will revolutionize our understanding of the formation and evolution of massive black holes along cosmic history by probing massive black hole binaries in the $10^3-10^7$ solar mass range out to redshift $z\\gtrsim 10$. High signal-to-noise ratio detections of $\\sim 10-100$ binary coalescences per year will allow accurate measurements of the parameters of individual binaries (such as their masses, spins and luminosity distance), and a deep understanding of the underlying cosmic massive black hole parent population. This wealth of unprecedented information can lead to breakthroughs in many areas of physics, including astrophysics, cosmology and fundamental physics. We review the current status of the field, recent progress and future challenges.

Enrico Barausse; Jillian Bellovary; Emanuele Berti; Kelly Holley-Bockelmann; Brian Farris; Bangalore Sathyaprakash; Alberto Sesana

2015-01-09T23:59:59.000Z

229

THE PAIR FRACTION OF MASSIVE GALAXIES AT 0 {<=} z {<=} 3  

SciTech Connect

Using a mass-selected (M{sub *} {>=} 10{sup 11} M{sub Sun }) sample of 198 galaxies at 0 {<=} z {<=} 3.0 with Hubble Space Telescope/NICMOS H{sub 160}-band images from the COSMOS survey, we find evidence for the evolution of the pair fraction above z {approx} 2, an epoch in which massive galaxies are believed to undergo significant structural and mass evolution. We observe that the pair fraction of massive galaxies is 0.15 {+-} 0.08 at 1.7 {<=}z {<=} 3.0, where galaxy pairs are defined as massive galaxies having a companion of flux ratio from 1:1 to 1:4 within a projected separation of 30 kpc. This is slightly lower but still consistent with the pair fraction measured previously in other studies, and the merger fraction predicted in halo-occupation modeling. The redshift evolution of the pair fraction is described by a power law F(z) = (0.07 {+-} 0.04) Multiplication-Sign (1 + z){sup 0.6{+-}0.5}. The merger rate is consistent with no redshift evolution; however it is difficult to constrain due to the limited sample size and the high uncertainties in the merging timescale. Based on the merger rate calculation, we estimate that a massive galaxy undergoes on average 1.1 {+-} 0.5 major mergers from z = 3 to 0. The observed merger fraction is sufficient to explain the number density evolution of massive galaxies, but insufficient to explain the size evolution. This is a hint that mechanism(s) other than major merging may be required to increase the sizes of the massive, compact quiescent galaxies from z {approx} 2 to 0.

Man, Allison W. S.; Toft, Sune; Zirm, Andrew W. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen (Denmark); Wuyts, Stijn [Max-Planck-Institut fuer Extraterrestrische Physik, Garching bei Muenchen (Germany); Van der Wel, Arjen, E-mail: allison@dark-cosmology.dk, E-mail: sune@dark-cosmology.dk, E-mail: azirm@dark-cosmology.dk, E-mail: swuyts@mpe.mpg.de, E-mail: vdwel@mpia.de [Max-Planck-Institut fuer Astronomie, Heidelberg (Germany)

2012-01-10T23:59:59.000Z

230

Parallel Computations of Natural Convection Flow in a Tall Cavity Using an Explicit Finite Element Method  

SciTech Connect

The Galerkin Finite Element Method was used to predict a natural convection flow in an enclosed cavity. The problem considered was a differentially heated, tall (8:1), rectangular cavity with a Rayleigh number of 3.4 x 10{sup 5} and Prandtl number of 0.71. The incompressible Navier-Stokes equations were solved using a Boussinesq approximation for the buoyancy force. The algorithm was developed for efficient use on massively parallel computer systems. Emphasis was on time-accurate simulations. It was found that the average temperature and velocity values can be captured with a relatively coarse grid, while the oscillation amplitude and period appear to be grid sensitive and require a refined computation.

Dunn, T.A.; McCallen, R.C.

2000-10-17T23:59:59.000Z

231

One-loop divergences in massive gravity theory  

E-Print Network (OSTI)

The one-loop divergences are calculated for the recently proposed ghost-free version of massive gravity, where the action depends on both metric and external tensor field f. The non-polynomial structure of the massive term is reduced to a more standard form by means of auxiliary tensor field, which is settled on-shell after quantum calculations are performed. As one should expect, the counterterms do not reproduce the form of the classical action. Moreover, the result has the form of the power series in f.

Ioseph L. Buchbinder; Dante D. Pereira; Ilya L. Shapiro

2012-01-16T23:59:59.000Z

232

Energy momentum flows for the massive vector field  

E-Print Network (OSTI)

We present a causal trajectory interpretation for the massive vector field, based on the flows of rest energy and a conserved density defined using the time-like eigenvectors and eigenvalues of the stress-energy-momentum tensor. This work extends our previous work which used a similar procedure for the scalar field. The massive, spin-one, complex vector field is discussed in detail and solutions are classified using the Pauli-Lubanski spin vector. The flows of energy-momentum are illustrated in a simple example of standing waves in a plane.

George Horton; Chris Dewdney

2006-09-26T23:59:59.000Z

233

On Solutions of Minimal Massive 3D Gravity  

E-Print Network (OSTI)

We look at solutions of Minimal Massive Gravity (MMG), a generalisation of Topologically Massive Gravity (TMG) that improves upon its holographic properties. It is shown that generically (in MMG parameter space) all conformally flat solutions of vacuum MMG are locally isometric to one of the two (A)dS vacua of the theory. We then couple a scalar field, and find that domain wall solutions can only interpolate between these two vacua precisely when the bulk graviton is tachyonic. Finally, we find a non-BTZ AdS black hole solution satisfying Brown-Henneaux boundary conditions, which lies within the "bulk/ boundary unitarity region".

Arvanitakis, Alex S

2015-01-01T23:59:59.000Z

234

Kinematic calibration of the parallel Argos mechanism  

Science Journals Connector (OSTI)

This paper deals with the kinematic calibration of the Argos mechanism which is a novel, spherical parallel structure having 3 rotational degrees of freedom. Its design is based on 3 actuators carrying a pantograph each which are connected to the end-effector ... Keywords: Argos mechanism, Implicit calibration, Kinematic calibration, Parametric calibration models

Peter Vischer; Reymond Clavel

2000-11-01T23:59:59.000Z

235

Instrumentation for parallel magnetic resonance imaging  

E-Print Network (OSTI)

of the art of parallel MR imaging. First, a low-cost desktop MR scanner was developed (< $13,000) for imaging small samples (2.54 cm fields-of view) at low magnetic field strengths (< 0.25 T). The performance of the prototype was verified through bench...

Brown, David Gerald

2007-04-25T23:59:59.000Z

236

Original article Parallel selection of ethanol  

E-Print Network (OSTI)

Original article Parallel selection of ethanol and acetic-acid tolerance in Drosophila melanogaster significantly with latitude (0.036 ! 0.004 for 1° latitude; genetic divergence FST = 0.25). Patterns of ethanol of latitudinal ethanol tolerance (10 to 15%) and acetic-acid tolerance (3.7 to 13.2%) were observed in adult

Paris-Sud XI, Université de

237

WEBPIE: A WEB-SCALE PARALLEL INFERENCE  

E-Print Network (OSTI)

WEBPIE: A WEB-SCALE PARALLEL INFERENCE ENGINE Jacopo Urbani, Spyros Kotoulas, Jason Maassen, Niels Amsterdam Monday 10 May 2010 #12;The Semantic Web The Semantic Web is an extension of the current Web where the semantics is defined Basically the idea is to move from Web of Documents (Traditional Web) Web of data

238

A more general form for parallel springs  

Science Journals Connector (OSTI)

The well-known result for the addition of springs in parallel assumes that the springs are constrained to compress the same amount. We consider the implications of removing this constraint by holding one end of each spring fixed but allowing the other ends to compress as needed to achieve static equilibrium.

Timothy J. Folkerts

2002-01-01T23:59:59.000Z

239

Parallelized Interpolation: A Quantitative Assessment Scott Blaha  

E-Print Network (OSTI)

Parallelized Interpolation: A Quantitative Assessment Scott Blaha Swarthmore College Mustafa Paksoy- cent I/O-efficient point cloud to DEM algorithm (0), from 52% to 86% of running time was spent inter-off in interpolation is quality (e.g. representativeness) of the resulting DEM ver- sus the computational complexity

Danner, Andrew

240

Parallel implementation of AutoDock  

Science Journals Connector (OSTI)

AutoDock, a widely used docking algorithm, has been implemented in a parallel version. A near-linear increase in speed has been observed even with 96 processors, making it possible to carry out high-throughput docking, likely to have a significant impact on structure-based drug design.

Khodade, P.

2007-05-15T23:59:59.000Z

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


241

Parallel MATLAB: Single Program Multiple Data  

E-Print Network (OSTI)

Parallel MATLAB: Single Program Multiple Data John Burkardt (FSU) Gene Cliff (AOE/ICAM - ecliff: Advanced Research Computing ICAM: Interdisciplinary Center for Applied Mathematics 1 / 69 #12;Matlab ( 'myscript', 'Profile', ... 'ithaca_R2012a', 'matlabpool', 7 ) 5 / 69 #12;SPMD: The SPMD Environment Matlab

Crawford, T. Daniel

242

Swift: A language for distributed parallel scripting  

Science Journals Connector (OSTI)

Scientists, engineers, and statisticians must execute domain-specific application programs many times on large collections of file-based data. This activity requires complex orchestration and data management as data is passed to, from, and among application ... Keywords: Dataflow, Parallel programming, Scripting, Swift

Michael Wilde; Mihael Hategan; Justin M. Wozniak; Ben Clifford; Daniel S. Katz; Ian Foster

2011-09-01T23:59:59.000Z

243

Performance studies of the parallel VIM code  

SciTech Connect

In this paper, we evaluate the performance of the parallel version of the VIM Monte Carlo code on the IBM SPx at the High Performance Computing Research Facility at Argonne National Laboratory. Three test problems with contrasting computational characteristics were used to assess effects in performance. A statistical method for estimating the inefficiencies due to load imbalance and communication is also introduced.

Shi, B.; Blomquist, R.N. [Argonne National Laboratory, IL (United States)

1996-12-31T23:59:59.000Z

244

Performance studies of the parallel VIM code  

SciTech Connect

In this paper, the authors evaluate the performance of the parallel version of the VIM Monte Carlo code on the IBM SPx at the High Performance Computing Research Facility at ANL. Three test problems with contrasting computational characteristics were used to assess effects in performance. A statistical method for estimating the inefficiencies due to load imbalance and communication is also introduced. VIM is a large scale continuous energy Monte Carlo radiation transport program and was parallelized using history partitioning, the master/worker approach, and p4 message passing library. Dynamic load balancing is accomplished when the master processor assigns chunks of histories to workers that have completed a previously assigned task, accommodating variations in the lengths of histories, processor speeds, and worker loads. At the end of each batch (generation), the fission sites and tallies are sent from each worker to the master process, contributing to the parallel inefficiency. All communications are between master and workers, and are serial. The SPx is a scalable 128-node parallel supercomputer with high-performance Omega switches of 63 {micro}sec latency and 35 MBytes/sec bandwidth. For uniform and reproducible performance, they used only the 120 identical regular processors (IBM RS/6000) and excluded the remaining eight planet nodes, which may be loaded by other`s jobs.

Shi, B.; Blomquist, R.N. [Argonne National Lab., IL (United States). Reactor Analysis Div.

1996-05-01T23:59:59.000Z

245

Analysis of the parallel distinguished point tradeoff  

Science Journals Connector (OSTI)

Cryptanalytic time memory tradeoff algorithms are tools for quickly inverting one-way functions and many consider the rainbow table method to be the most efficient tradeoff algorithm. However, it was recently announced, mostly based on experiments, that ... Keywords: distinguished point, parallel distinguished point, rainbow table, time memory tradeoff

Jin Hong; Ga Won Lee; Daegun Ma

2011-12-01T23:59:59.000Z

246

Parallel programming with PCN. Revision 2  

SciTech Connect

PCN is a system for developing and executing parallel programs. It comprises a high-level programming language, tools for developing and debugging programs in this language, and interfaces to Fortran and Cthat allow the reuse of existing code in multilingual parallel programs. Programs developed using PCN are portable across many different workstations, networks, and parallel computers. This document provides all the information required to develop parallel programs with the PCN programming system. It includes both tutorial and reference material. It also presents the basic concepts that underlie PCN, particularly where these are likely to be unfamiliar to the reader, and provides pointers to other documentation on the PCN language, programming techniques, and tools. PCN is in the public domain. The latest version of both the software and this manual can be obtained by anonymous ftp from Argonne National Laboratory in the directory pub/pcn at info.mcs. ani.gov (cf. Appendix A). This version of this document describes PCN version 2.0, a major revision of the PCN programming system. It supersedes earlier versions of this report.

Foster, I.; Tuecke, S.

1993-01-01T23:59:59.000Z

247

Decomposing Linear Programs for Parallel Solution?  

E-Print Network (OSTI)

Decomposing Linear Programs for Parallel Solution? Ali P nar, Umit V. Catalyurek, Cevdet Aykanat in the solution of Linear Programming (LP) problems with block angular constraint matrices has been exploited industrial applications and the advent of powerful computers have in- creased the users' ability to formulate

�atalyürek, �mit V.

248

Decomposing Linear Programs for Parallel Solution ?  

E-Print Network (OSTI)

Decomposing Linear Programs for Parallel Solution ? Ali Pinar, ¨ Umit V. C¸ ataly¨urek, Cevdet in the solution of Linear Programming (LP) problems with block angular constraint matrices has been exploited with successful industrial applications and the advent of powerful computers have in­ creased the users' ability

�atalyürek, �mit V.

249

VIP-FS: A Virtual, Parallel file System for High Performance Parallel and Distributed Computing *  

E-Print Network (OSTI)

-passing li- blclries only provide part of the support necessary for most high performan.ce distributed computing applzca- tzcjns - support for hagh speed parallel l/O is still lark- 211q. In this paper, we

Kuzmanovic, Aleksandar

250

Data communications in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Data communications in a parallel active messaging interface ('PAMI') or a parallel computer, the parallel computer including a plurality of compute nodes that execute a parallel application, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution of a compute node, including specification of a client, a context, and a task, the compute nodes and the endpoints coupled for data communications instruction, the instruction characterized by instruction type, the instruction specifying a transmission of transfer data from the origin endpoint to a target endpoint and transmitting, in accordance witht the instruction type, the transfer data from the origin endpoin to the target endpoint.

Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

2014-02-11T23:59:59.000Z

251

Data communications in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the parallel computer including a plurality of compute nodes that execute a parallel application, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes and the endpoints coupled for data communications through the PAMI and through data communications resources, including receiving in an origin endpoint of the PAMI a data communications instruction, the instruction characterized by an instruction type, the instruction specifying a transmission of transfer data from the origin endpoint to a target endpoint and transmitting, in accordance with the instruction type, the transfer data from the origin endpoint to the target endpoint.

Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

2013-10-29T23:59:59.000Z

252

Sequential and parallel algorithms for minimum cost parallel decomposition of finite state machines  

E-Print Network (OSTI)

form a lattice, where each node in the lattice has a cost associated with it. An algorithm to build the lattice is presented. Also to find the best pos- sible parallel decomposition, an optimal cost algorithm is proposed. Sequential snd parallel.... The OSI Reference Model C. Bottlenecks in Communication Protocols D. High Speed Protocols E. High-Speed Implementations F. Structure of the Thesis THEORETICAL BACKGROUND A. Set Theory . B. Partially Ordered Sets and Lattices C. Sequential Machines...

Shelke, Rajendra Ram

1992-01-01T23:59:59.000Z

253

Massive Pellet and Rupture Disk Testing for Disruption Mitigation Applications  

SciTech Connect

Injection of massive quantities of noble gases or D2 has proven to be effective at mitigating some of the deleterious effects of disruptions in tokamaks. Two alternative methods that might offer some advantages over the present technique for massive gas injection are shattering massive pellets and employing close-coupled rupture disks. Laboratory testing has been carried out to evaluate their feasibility. For the study of massive pellets, a pipe gun pellet injector cooled with a cryogenic refrigerator was fitted with a relatively large barrel (16.5 mm bore), and D2 and Ne pellets were made and were accelerated to speeds of ~600 and 300 m/s, respectively. Based on the successful proof-of-principle testing with the injector and a special double-impact target to shatter pellets, a similar system has been prepared and installed on DIII-D and should be ready for experiments later this year. To study the applicability of rupture disks for disruption mitigation, a simple test apparatus was assembled in the lab. Commercially available rupture disks of 1 in. nominal diameter were tested at conditions relevant for the application on tokamaks, including tests with Ar and He gases and rupture pressures of ~54 bar. Some technical and practical issues of implementing this technique on a tokamak are discussed.

Combs, Stephen Kirk [ORNL] [ORNL; Meitner, Steven J [ORNL] [ORNL; Baylor, Larry R [ORNL] [ORNL; Caughman, John B [ORNL] [ORNL; Commaux, Nicolas JC [ORNL] [ORNL; Fehling, Dan T [ORNL] [ORNL; Foust, Charles R [ORNL] [ORNL; Jernigan, Thomas C [ORNL] [ORNL; McGill, James M [ORNL] [ORNL; Parks, P. B. [General Atomics] [General Atomics; Rasmussen, David A [ORNL] [ORNL

2009-01-01T23:59:59.000Z

254

THE FORMATION AND EVOLUTION OF THE FIRST MASSIVE BLACK HOLES  

E-Print Network (OSTI)

@astron.berkeley.edu Abstract The first massive astrophysical black holes likely formed at high redshifts (z > 10 (Eddington) luminosity, and converts mass to radiation with an efficiency of = Mc2 /LEdd 10%) and using to link the evolution of quasars with that of dark matter halos condensing in a cold dark matter (CDM

Wurtele, Jonathan

255

Delusional Boot: Securing Cloud Hypervisors without Massive Re-engineering  

E-Print Network (OSTI)

Delusional Boot: Securing Cloud Hypervisors without Massive Re-engineering Anh Nguyen , Himanshu an obstacle: the boot process of many commodity OSes depends on legacy virtual devices absent from our hypervisor. Min-V introduces delusional boot, a mechanism that allows guest VMs run- ning commodity OSes

Hunt, Galen

256

X-ray Emission from Massive Stars David Cohen  

E-Print Network (OSTI)

X-ray Emission from Massive Stars David Cohen Department of Physics and Astronomy Swarthmore University, Oct. 13, 2005 astro.swarthmore.edu/~cohen/ #12;Outline 1. What you need to know: a. X-rays from the Sun - magnetic activity, x-ray spectra b. Hot stars c. Radiation-driven winds and the Doppler shift d

Cohen, David

257

A parallel world in the dark  

SciTech Connect

The baryon-dark matter coincidence is a long-standing issue. Interestingly, the recent observations suggest the presence of dark radiation, which, if confirmed, would pose another coincidence problem of why the density of dark radiation is comparable to that of photons. These striking coincidences may be traced back to the dark sector with particle contents and interactions that are quite similar, if not identical, to the standard model: a dark parallel world. It naturally solves the coincidence problems of dark matter and dark radiation, and predicts a sterile neutrino(s) with mass of O(0.1?1) eV, as well as self-interacting dark matter made of the counterpart of ordinary baryons. We find a robust prediction for the relation between the abundance of dark radiation and the sterile neutrino, which can serve as the smoking-gun evidence of the dark parallel world.

Higaki, Tetsutaro [Mathematical Physics Lab., RIKEN Nishina Center, Saitama 351-0198 (Japan); Jeong, Kwang Sik; Takahashi, Fuminobu, E-mail: tetsutaro.higaki@riken.jp, E-mail: ksjeong@tuhep.phys.tohoku.ac.jp, E-mail: fumi@tuhep.phys.tohoku.ac.jp [Department of Physics, Tohoku University, Sendai 980-8578 (Japan)

2013-08-01T23:59:59.000Z

258

Parallel machine architecture for production rule systems  

DOE Patents (OSTI)

A parallel processing system for production rule programs utilizes a host processor for storing production rule right hand sides (RHS) and a plurality of rule processors for storing left hand sides (LHS). The rule processors operate in parallel in the recognize phase of the system recognize -Act Cycle to match their respective LHS's against a stored list of working memory elements (WME) in order to find a self consistent set of WME's. The list of WME is dynamically varied during the Act phase of the system in which the host executes or fires rule RHS's for those rules for which a self-consistent set has been found by the rule processors. The host transmits instructions for creating or deleting working memory elements as dictated by the rule firings until the rule processors are unable to find any further self-consistent working memory element sets at which time the production rule system is halted.

Allen, Jr., John D. (Knoxville, TN); Butler, Philip L. (Knoxville, TN)

1989-01-01T23:59:59.000Z

259

Implementation of a cell-wise Block-Gauss-Seidel iterative method for SN transport on a hybrid parallel computer architecture  

SciTech Connect

We have implemented a cell-wise, block-Gauss-Seidel (bGS) iterative algorithm, for the solution of the S{sub n} transport equations on the Roadrunner hybrid, parallel computer architecture. A compute node of this massively parallel machine comprises AMD Opteron cores that are linked to a Cell Broadband Engine{trademark} (Cell/B.E.). LAPACK routines have been ported to the Cell/B.E. in order to make use of its parallel Synergistic Processing Elements (SPEs). The bGS algorithm is based on the LU factorization and solution of a linear system that couples the fluxes for all S{sub n} angles and energy groups on a mesh cell. For every cell of a mesh that has been parallel decomposed on the higher-level Opteron processors, a linear system is transferred to the Cell/B.E. and the parallel LAPACK routines are used to compute a solution, which is then transferred back to the Opteron, where the rest of the computations for the S{sub n} transport problem take place. Compared to standard parallel machines, a hundred-fold speedup of the bGS was observed on the hybrid Roadrunner architecture. Numerical experiments with strong and weak parallel scaling demonstrate the bGS method is viable and compares favorably to full parallel sweeps (FPS) on two-dimensional, unstructured meshes when it is applied to optically thick, multi-material problems. As expected, however, it is not as efficient as FPS in optically thin problems.

Rosa, Massimiliano [Los Alamos National Laboratory; Warsa, James S [Los Alamos National Laboratory; Perks, Michael [Los Alamos National Laboratory

2010-12-14T23:59:59.000Z

260

On Parallelizing Dual Decomposition in Stochastic Integer Programming |  

NLE Websites -- All DOE Office Websites (Extended Search)

On Parallelizing Dual Decomposition in Stochastic Integer Programming On Parallelizing Dual Decomposition in Stochastic Integer Programming Title On Parallelizing Dual Decomposition in Stochastic Integer Programming Publication Type Journal Article Year of Publication 2013 Authors Lubin, M, Martin, K, Petra, CG, Sandikci, B Journal Operations Research Letters Volume 41 Start Page 252-258 Issue 3 Date Published 05/2013 Other Numbers ANL/MCS-P3037-0912 Abstract For stochastic mixed-integer programs, we revisit the dual decomposition algorithm of Care and Schultz from a computational perspective with the aim of its parallelization. We address an important bottleneck of parallel execution by identifying a formulation that permits the parallel solution of the master program by using structure-exploiting interior-point solvers. Our results demonstrate the potential for parallel speedup and the importance of regularization (stabilization) in the dual optimization. Load imbalance is identified as a remaining barrier to parallel scalability.

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


261

Shared Memory Parallel Programming with Entry Consistency for Distributed Memory  

E-Print Network (OSTI)

Midway: Shared Memory Parallel Programming with Entry Consistency for Distributed Memory to ensure a correctly functioning program. Midway is a shared memory parallel programming system which addresses the problem of excessive communication in a distributed memory multiprocessor. Midway programs

262

Parallel and Distributed Multi-Algorithm Circuit Simulation  

E-Print Network (OSTI)

With the proliferation of parallel computing, parallel computer-aided design (CAD) has received significant research interests. Transient transistor-level circuit simulation plays an important role in digital/analog circuit design and verification...

Dai, Ruicheng

2012-10-19T23:59:59.000Z

263

Efficient Parallel Refinement for Hierarchical Radiosity on a DSM computer  

E-Print Network (OSTI)

Efficient Parallel Refinement for Hierarchical Radiosity on a DSM computer François X. Sillion memory (DSM) parallel architecture. Our task definition is based on a very fine grain decompo- sition

Paris-Sud XI, Université de

264

Generic implementations of parallel prefix sums and its applications  

E-Print Network (OSTI)

Parallel prefix sums algorithms are one of the simplest and most useful building blocks for constructing parallel algorithms. A generic implementation is valuable because of the wide range of applications for this method. This thesis presents a...

Huang, Tao

2009-05-15T23:59:59.000Z

265

A Taxonomy of Parallel Prefix Networks David Harris  

E-Print Network (OSTI)

A Taxonomy of Parallel Prefix Networks David Harris Harvey Mudd College / Sun Microsystems Laboratories 301 E. Twelfth St. Claremont, CA 91711 David_Harris@hmc.edu Abstract - Parallel prefix networks

Harris, David Money

266

Parallel algorithms and architectures for low power video decoding  

E-Print Network (OSTI)

Parallelism coupled with voltage scaling is an effective approach to achieve high processing performance with low power consumption. This thesis presents parallel architectures and algorithms designed to deliver the power ...

Sze, Vivienne

2010-01-01T23:59:59.000Z

267

A Parallel Graph Partitioner for STAPL  

E-Print Network (OSTI)

A PARALLEL GRAPH PARTITIONER FOR STAPL A Thesis by NICOLAS CASTET Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair... of Committee, Nancy M. Amato Co-Chair of Committee, Lawrence Rauchwerger Committee Member, Marvin L. Adams Department Head, Duncan M. Walker May 2013 Major Subject: Computer Science Copyright 2013 Nicolas Castet ABSTRACT Multi-core architectures...

Castet, Nicolas

2013-04-26T23:59:59.000Z

268

Fluid Mixtures of Parallel Hard Cubes  

Science Journals Connector (OSTI)

The direct correlation function of a fluid mixture of parallel hard cubes is obtained by using Rosenfeld's fundamental measure approximation. This approximation is thermodynamically consistent (compressibility and virial equations of state are equal) and predicts a spinodal instability of the binary mixture for large-to-small side ratio larger than roughly 10, in qualitative agreement with simulations on the lattice version of the model. In two dimensions the system never demixes, also in agreement with the simulations.

José A. Cuesta

1996-05-13T23:59:59.000Z

269

Massive Hydraulic Fracture of Fenton Hill HDR Well EE-3 | Open...  

Open Energy Info (EERE)

Massive Hydraulic Fracture of Fenton Hill HDR Well EE-3 Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Massive Hydraulic Fracture of Fenton Hill HDR...

270

Xyce parallel electronic simulator : reference guide.  

SciTech Connect

This document is a reference guide to the Xyce Parallel Electronic Simulator, and is a companion document to the Xyce Users Guide. The focus of this document is (to the extent possible) exhaustively list device parameters, solver options, parser options, and other usage details of Xyce. This document is not intended to be a tutorial. Users who are new to circuit simulation are better served by the Xyce Users Guide. The Xyce Parallel Electronic Simulator has been written to support, in a rigorous manner, the simulation needs of the Sandia National Laboratories electrical designers. It is targeted specifically to run on large-scale parallel computing platforms but also runs well on a variety of architectures including single processor workstations. It also aims to support a variety of devices and models specific to Sandia needs. This document is intended to complement the Xyce Users Guide. It contains comprehensive, detailed information about a number of topics pertinent to the usage of Xyce. Included in this document is a netlist reference for the input-file commands and elements supported within Xyce; a command line reference, which describes the available command line arguments for Xyce; and quick-references for users of other circuit codes, such as Orcad's PSpice and Sandia's ChileSPICE.

Mei, Ting; Rankin, Eric Lamont; Thornquist, Heidi K.; Santarelli, Keith R.; Fixel, Deborah A.; Coffey, Todd Stirling; Russo, Thomas V.; Schiek, Richard Louis; Warrender, Christina E.; Keiter, Eric Richard; Pawlowski, Roger Patrick

2011-05-01T23:59:59.000Z

271

Parallel algorithm strategies for circuit simulation.  

SciTech Connect

Circuit simulation tools (e.g., SPICE) have become invaluable in the development and design of electronic circuits. However, they have been pushed to their performance limits in addressing circuit design challenges that come from the technology drivers of smaller feature scales and higher integration. Improving the performance of circuit simulation tools through exploiting new opportunities in widely-available multi-processor architectures is a logical next step. Unfortunately, not all traditional simulation applications are inherently parallel, and quickly adapting mature application codes (even codes designed to parallel applications) to new parallel paradigms can be prohibitively difficult. In general, performance is influenced by many choices: hardware platform, runtime environment, languages and compilers used, algorithm choice and implementation, and more. In this complicated environment, the use of mini-applications small self-contained proxies for real applications is an excellent approach for rapidly exploring the parameter space of all these choices. In this report we present a multi-core performance study of Xyce, a transistor-level circuit simulation tool, and describe the future development of a mini-application for circuit simulation.

Thornquist, Heidi K.; Schiek, Richard Louis; Keiter, Eric Richard

2010-01-01T23:59:59.000Z

272

ParCAT: Parallel Climate Analysis Toolkit  

SciTech Connect

Climate science is employing increasingly complex models and simulations to analyze the past and predict the future of Earth s climate. This growth in complexity is creating a widening gap between the data being produced and the ability to analyze the datasets. Parallel computing tools are necessary to analyze, compare, and interpret the simulation data. The Parallel Climate Analysis Toolkit (ParCAT) provides basic tools to efficiently use parallel computing techniques to make analysis of these datasets manageable. The toolkit provides the ability to compute spatio-temporal means, differences between runs or differences between averages of runs, and histograms of the values in a data set. ParCAT is implemented as a command-line utility written in C. This allows for easy integration in other tools and allows for use in scripts. This also makes it possible to run ParCAT on many platforms from laptops to supercomputers. ParCAT outputs NetCDF files so it is compatible with existing utilities such as Panoply and UV-CDAT. This paper describes ParCAT and presents results from some example runs on the Titan system at ORNL.

Smith, Brian E [ORNL; Steed, Chad A [ORNL; Shipman, Galen M [ORNL; Ricciuto, Daniel M [ORNL; Thornton, Peter E [ORNL; Wehner, Michael [Lawrence Berkeley National Laboratory (LBNL); Williams, Dean N. [Lawrence Livermore National Laboratory (LLNL)

2013-01-01T23:59:59.000Z

273

Automation of Fluorous Solid-Phase Extraction for Parallel Synthesis  

Science Journals Connector (OSTI)

Automation of Fluorous Solid-Phase Extraction for Parallel Synthesis ... • Cartridge conditioning, sample loading, elution, and rinsing are automated. ...

Wei Zhang; Yimin Lu

2006-10-17T23:59:59.000Z

274

Typed Fusion with Applications to Parallel and Sequential Code Generation  

E-Print Network (OSTI)

Typed Fusion with Applications to Parallel and Sequential Code Generation Ken Kennedy Kathryn S. Mc the granularity of parallel loops and for improving data locality. This paper introduces typed fusion and parallel program optimization. Typed fusion is more general and applicable than previous work. We present

McKinley, Kathryn S.

275

Control of Parallel Robots: Towards Very High Accelerations  

E-Print Network (OSTI)

parallel robot (for automated spray painting) to be built was patented by W. Pollard in 1942. A few yearsControl of Parallel Robots: Towards Very High Accelerations Ahmed Chemori, Guilherme Sartori-redundant parallel manipulators, where we are interested in control of PAR2 robot for 2D pick-and- place trajectories

Boyer, Edmond

276

Automatic parallelization of object oriented models executed with inline solvers  

Science Journals Connector (OSTI)

In this work we report preliminary results of automatically generating parallel code from equation-based models together at two levels: Performing inline expansion of a Runge-Kutta solver combined with fine-grained automatic parallelization of the resulting ... Keywords: automatic parallelization, modelica

Håkan Lundvall; Peter Fritzson

2007-09-01T23:59:59.000Z

277

Making Nested Parallel Transactions Practical using Lightweight Hardware Support  

E-Print Network (OSTI)

Making Nested Parallel Transactions Practical using Lightweight Hardware Support Woongki Baek possible performance, TM must support the nested parallelism available in real-world applications and sup- ported by popular programming models. A few recent papers have proposed support for nested parallelism

Kozyrakis, Christos

278

Cloud Futures Workshop 2010 Cloud Computing Support for Massively Social Gaming Alexandru Iosup  

E-Print Network (OSTI)

1 Cloud Futures Workshop 2010 ­ Cloud Computing Support for Massively Social Gaming Alexandru Iosup Pierre (Vrije U.). Cloud Computing Support for Massively Social Gaming (Rain for the Thirsty) #12;Cloud Futures Workshop 2010 ­ Cloud Computing Support for Massively Social Gaming 2 Intermezzo: Tips on how

Iosup, Alexandru

279

An implementation of a parallel graphics algorithm on a distributed-memory message-passing parallel computer  

E-Print Network (OSTI)

that the first phase is already implemented on the sequential or parallel computer and the database is optimally dis- tributed among the nodes of the parallel computer, the second phase is implemented on the general-purpose niulticomputer, the nCUBE hypercube... parallel computer. The object space of an image scene is first organized in the candidate object grid, which is distributed among the processors of the nCUBE parallel multicomputer. Then each processor detects simultaneously the intersections...

Kwon, Young-Jun

2012-06-07T23:59:59.000Z

280

Secretary Chu Announces New Institute to Help Scientists Improve Massive  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

New Institute to Help Scientists Improve New Institute to Help Scientists Improve Massive Data Set Research on DOE Supercomputers Secretary Chu Announces New Institute to Help Scientists Improve Massive Data Set Research on DOE Supercomputers March 29, 2012 - 2:48pm Addthis Washington D.C. - Energy Secretary Steven Chu today announced $5 million to establish the Scalable Data Management, Analysis and Visualization (SDAV) Institute as part of the Obama Administration's "Big Data Research and Development Initiative," which was announced this morning and takes aim at improving the nation's ability to extract knowledge and insights from large and complex collections of digital data. Led by the Energy Department's Lawrence Berkeley National Laboratory, the SDAV Institute will bring together the expertise of six national laboratories

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281

Lectures on BRS invariance for massive boson fields  

E-Print Network (OSTI)

These notes correspond to lectures given at the Villa de Leyva Summer School in Colombia (July 2007). Our main purpose in this short course on BRS invariance of gauge theories is to illuminate corners of the theory left in the shade by standard treatments. The plan is as follows. First a review of Utiyama's "general gauge theory". Promptly we find a counterexample to it in the shape of the massive spin-1 Stueckelberg gauge field. This is not fancy, as the massive case is the most natural one to introduce BRS invariance in the context of free quantum fields. Mathematically speaking, the first part of the course uses Utiyama's notation, and thus has the flavour and non-intrinsic notation of standard physics textbooks. Next we deal with boson fields on Fock space and BRS invariance in connection with the existence of Krein operators; the attending rigour points are then addressed.

Gracia-Bondia, Jose M

2008-01-01T23:59:59.000Z

282

Secular stability and instability in stellar systems surrounding massive objects  

E-Print Network (OSTI)

We examine the stability of a low-mass stellar system surrounding a massive central object. Examples of such systems include the centers of galaxies or star clusters containing a massive black hole, and the Oort comet cloud. If the self-gravity of the stellar system is the dominant non-Keplerian force, such systems may be subject to slowly growing (secular) lopsided instabilities. Stability to secular modes is largely determined by the dependence of the distribution function F on angular momentum J. If dF/dJ 0, as is expected if there is a loss cone at low angular momentum, all spherical systems in which F=0 at J=0 (an empty loss cone) are only neutrally stable, and flattened, non-rotating systems are generally unstable. These results suggest that secular instabilities may dominate the structure and evolution of the stellar systems in the centers of galaxies.

Scott Tremaine

2004-12-13T23:59:59.000Z

283

Lectures on BRS invariance for massive boson fields  

E-Print Network (OSTI)

These notes correspond to lectures given at the Villa de Leyva Summer School in Colombia (July 2007). Our main purpose in this short course on BRS invariance of gauge theories is to illuminate corners of the theory left in the shade by standard treatments. The plan is as follows. First a review of Utiyama's "general gauge theory". Promptly we find a counterexample to it in the shape of the massive spin-1 Stueckelberg gauge field. This is not fancy, as the massive case is the most natural one to introduce BRS invariance in the context of free quantum fields. Mathematically speaking, the first part of the course uses Utiyama's notation, and thus has the flavour and non-intrinsic notation of standard physics textbooks. Next we deal with boson fields on Fock space and BRS invariance in connection with the existence of Krein operators; the attending rigour points are then addressed.

Jose M. Gracia-Bondia

2010-04-26T23:59:59.000Z

284

Analyzing Massive Machine Maintenance Data in a Computing Cloud  

Science Journals Connector (OSTI)

We present a novel framework, CloudView, for storage, processing and analysis of massive machine maintenance data, collected from a large number of sensors embedded in industrial machines, in a cloud computing environment. This paper describes the architecture, ... Keywords: Sensors,Real time systems,Data analysis,Reliability,Cloud computing,Wind turbines,Maintenance engineering,MapReduce,Fault prediction,machine data analysis,case-based reasoning,cloud computing,Hadoop

Arshdeep Bahga; Vijay K. Madisetti

2012-10-01T23:59:59.000Z

285

Deconfined SU(2) phase with a massive vector boson triplet  

E-Print Network (OSTI)

We introduce a model of SU(2) and U(1) vector fields with a local U(2) symmetry. Its action can be obtained in the London limit of a gauge invariant regularization involving two scalar fields. Evidence from lattice simulations of the model supports a (zero temperature) SU(2) deconfining phase transition through breaking of the SU(2) center symmetry, and a massive vector boson triplet is found in the deconfined phase.

Bernd A. Berg

2010-11-29T23:59:59.000Z

286

Hanford Waste Treatment Plant Sets Massive Protective Shield door in  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Waste Treatment Plant Sets Massive Protective Shield door Waste Treatment Plant Sets Massive Protective Shield door in Pretreatment Facility Hanford Waste Treatment Plant Sets Massive Protective Shield door in Pretreatment Facility January 12, 2011 - 12:00pm Addthis The carbon steel doors come together to form an upside-down L-shape. The 102-ton door was set on top of the 85-ton door that was installed at the end of December. The carbon steel doors come together to form an upside-down L-shape. The 102-ton door was set on top of the 85-ton door that was installed at the end of December. The 102-ton shield door measures 52 feet wide and 15 feet tall The 102-ton shield door measures 52 feet wide and 15 feet tall The carbon steel doors come together to form an upside-down L-shape. The 102-ton door was set on top of the 85-ton door that was installed at the end of December.

287

Probing Massive Stars Around Gamma-Ray Burst Progenitors  

E-Print Network (OSTI)

Long Gamma-Ray Bursts (GRBs) are produced by ultra-relativistic jets launched from core collapse of massive stars. Most massive stars form in binaries and/or in star clusters, which means that there may be a significant external photon field (EPF) around the GRB progenitor. We calculate the inverse-Compton scattering of EPF by the hot electrons in the GRB jet. Three possible cases of EPFs are considered: the progenitor is (I) in a massive binary system, (II) surrounded by a Wolf-Rayet-star wind, and (III) in a dense star cluster. Typical luminosities of 10^47 - 10^50 erg/s in the 10 - 100 GeV band are expected, depending on the stellar luminosity, binary separation (I), wind mass loss rate (II), stellar number density (III), etc. We calculate the lightcurve and spectrum in each case, taking fully into account the equal-arrival time surfaces and possible pair-production absorption with the prompt gamma-rays. Observations can put constraints on the existence of such EPFs (and hence on the nature of GRB progenit...

Lu, Wenbin; Smoot, George F

2015-01-01T23:59:59.000Z

288

Three dimensional Casimir piston for massive scalar fields  

E-Print Network (OSTI)

We consider Casimir force acting on a three dimensional rectangular piston due to a massive scalar field subject to periodic, Dirichlet and Neumann boundary conditions. Exponential cut-off method is used to derive the Casimir energy in the interior region and the exterior region separated by the piston. It is shown that the divergent term of the Casimir force acting on the piston due to the interior region cancels with that due to the exterior region, thus render a finite well-defined Casimir force acting on the piston. Explicit expressions for the total Casimir force acting on the piston is derived, which show that the Casimir force is always attractive for all the different boundary conditions considered. As a function of a -- the distance from the piston to the opposite wall, it is found that the magnitude of the Casimir force behaves like $1/a^4$ when $a\\to 0^+$ and decays exponentially when $a\\to \\infty$. Moreover, the magnitude of the Casimir force is always a decreasing function of a. On the other hand, passing from massless to massive, we find that the effect of the mass is insignificant when a is small, but the magnitude of the force is decreased for large a in the massive case.

S. C. Lim; L. P. Teo

2008-07-23T23:59:59.000Z

289

Parallelizing AT with MatlabMPI  

SciTech Connect

The Accelerator Toolbox (AT) is a high-level collection of tools and scripts specifically oriented toward solving problems dealing with computational accelerator physics. It is integrated into the MATLAB environment, which provides an accessible, intuitive interface for accelerator physicists, allowing researchers to focus the majority of their efforts on simulations and calculations, rather than programming and debugging difficulties. Efforts toward parallelization of AT have been put in place to upgrade its performance to modern standards of computing. We utilized the packages MatlabMPI and pMatlab, which were developed by MIT Lincoln Laboratory, to set up a message-passing environment that could be called within MATLAB, which set up the necessary pre-requisites for multithread processing capabilities. On local quad-core CPUs, we were able to demonstrate processor efficiencies of roughly 95% and speed increases of nearly 380%. By exploiting the efficacy of modern-day parallel computing, we were able to demonstrate incredibly efficient speed increments per processor in AT's beam-tracking functions. Extrapolating from prediction, we can expect to reduce week-long computation runtimes to less than 15 minutes. This is a huge performance improvement and has enormous implications for the future computing power of the accelerator physics group at SSRL. However, one of the downfalls of parringpass is its current lack of transparency; the pMatlab and MatlabMPI packages must first be well-understood by the user before the system can be configured to run the scripts. In addition, the instantiation of argument parameters requires internal modification of the source code. Thus, parringpass, cannot be directly run from the MATLAB command line, which detracts from its flexibility and user-friendliness. Future work in AT's parallelization will focus on development of external functions and scripts that can be called from within MATLAB and configured on multiple nodes, while expending minimal communication overhead with the integrated MATLAB library.

Li, Evan Y.; /Brown U. /SLAC

2011-06-22T23:59:59.000Z

290

Partitioning sparse rectangular matrices for parallel processing  

SciTech Connect

The authors are interested in partitioning sparse rectangular matrices for parallel processing. The partitioning problem has been well-studied in the square symmetric case, but the rectangular problem has received very little attention. They will formalize the rectangular matrix partitioning problem and discuss several methods for solving it. They will extend the spectral partitioning method for symmetric matrices to the rectangular case and compare this method to three new methods -- the alternating partitioning method and two hybrid methods. The hybrid methods will be shown to be best.

Kolda, T.G.

1998-05-01T23:59:59.000Z

291

Parallel State Estimation Assessment with Practical Data  

SciTech Connect

This paper presents a full-cycle parallel state estimation (PSE) implementation using a preconditioned conjugate gradient algorithm. The developed code is able to solve large-size power system state estimation within 5 seconds using real-world data, comparable to the Supervisory Control And Data Acquisition (SCADA) rate. This achievement allows the operators to know the system status much faster to help improve grid reliability. Case study results of the Bonneville Power Administration (BPA) system with real measurements are presented. The benefits of fast state estimation are also discussed.

Chen, Yousu; Jin, Shuangshuang; Rice, Mark J.; Huang, Zhenyu

2014-10-31T23:59:59.000Z

292

Parallel heater system for subsurface formations  

DOE Patents (OSTI)

A heating system for a subsurface formation is disclosed. The system includes a plurality of substantially horizontally oriented or inclined heater sections located in a hydrocarbon containing layer in the formation. At least a portion of two of the heater sections are substantially parallel to each other. The ends of at least two of the heater sections in the layer are electrically coupled to a substantially horizontal, or inclined, electrical conductor oriented substantially perpendicular to the ends of the at least two heater sections.

Harris, Christopher Kelvin (Houston, TX); Karanikas, John Michael (Houston, TX); Nguyen, Scott Vinh (Houston, TX)

2011-10-25T23:59:59.000Z

293

Carbothermic reduction with parallel heat sources  

DOE Patents (OSTI)

Disclosed are apparatus and method of carbothermic direct reduction for producing an aluminum alloy from a raw material mix including aluminum oxide, silicon oxide, and carbon wherein parallel heat sources are provided by a combustion heat source and by an electrical heat source at essentially the same position in the reactor, e.g., such as at the same horizontal level in the path of a gravity-fed moving bed in a vertical reactor. The present invention includes providing at least 79% of the heat energy required in the process by the electrical heat source.

Troup, Robert L. (Murrysville, PA); Stevenson, David T. (Washington Township, Washington County, PA)

1984-12-04T23:59:59.000Z

294

Switch for serial or parallel communication networks  

DOE Patents (OSTI)

A communication switch apparatus and a method for use in a geographically extensive serial, parallel or hybrid communication network linking a multi-processor or parallel processing system has a very low software processing overhead in order to accommodate random burst of high density data. Associated with each processor is a communication switch. A data source and a data destination, a sensor suite or robot for example, may also be associated with a switch. The configuration of the switches in the network are coordinated through a master processor node and depends on the operational phase of the multi-processor network: data acquisition, data processing, and data exchange. The master processor node passes information on the state to be assumed by each switch to the processor node associated with the switch. The processor node then operates a series of multi-state switches internal to each communication switch. The communication switch does not parse and interpret communication protocol and message routing information. During a data acquisition phase, the communication switch couples sensors producing data to the processor node associated with the switch, to a downlink destination on the communications network, or to both. It also may couple an uplink data source to its processor node. During the data exchange phase, the switch couples its processor node or an uplink data source to a downlink destination (which may include a processor node or a robot), or couples an uplink source to its processor node and its processor node to a downlink destination.

Crosette, Dario B. (DeSoto, TX)

1994-01-01T23:59:59.000Z

295

Switch for serial or parallel communication networks  

DOE Patents (OSTI)

A communication switch apparatus and a method for use in a geographically extensive serial, parallel or hybrid communication network linking a multi-processor or parallel processing system has a very low software processing overhead in order to accommodate random burst of high density data. Associated with each processor is a communication switch. A data source and a data destination, a sensor suite or robot for example, may also be associated with a switch. The configuration of the switches in the network are coordinated through a master processor node and depends on the operational phase of the multi-processor network: data acquisition, data processing, and data exchange. The master processor node passes information on the state to be assumed by each switch to the processor node associated with the switch. The processor node then operates a series of multi-state switches internal to each communication switch. The communication switch does not parse and interpret communication protocol and message routing information. During a data acquisition phase, the communication switch couples sensors producing data to the processor node associated with the switch, to a downlink destination on the communications network, or to both. It also may couple an uplink data source to its processor node. During the data exchange phase, the switch couples its processor node or an uplink data source to a downlink destination (which may include a processor node or a robot), or couples an uplink source to its processor node and its processor node to a downlink destination. 9 figs.

Crosette, D.B.

1994-07-19T23:59:59.000Z

296

Parallel barrier effectiveness, Dulles noise barrier project.  

Science Journals Connector (OSTI)

In an effort to minimize the cost and maximize the effectiveness of highway noise barriers the Federal Highway Administration (FHWA) and a National Pooled Fund Panel (made up of 14 states) funded a field study program on an experimental highway noise barrier. A test barrier was constructed in 1984 at a site at Dulles International Airport in Chantilly Virginia. The study conducted from May 1989 to August 1989 by the U.S. Department of Transportation Research and Special Programs Administration Transportation System Center (U.S. DOT/RSPA/TSC) focused on the use of absorptive treatment and tilting as a means of improving the insertion loss of two parallel highway noise barriers. Measurements were conducted with both controlled moving point sources (trucks) and an artificial fixed?point source (speaker system). Results show (1) the addition of absorptive treatment to the roadside face of two vertical parallel highway noise barriers eliminated multiple reflections and was found to improve the insertion loss (2–6 dB); (2) tilting proved to be an effective alternative to absorptive treatment in eliminating the multiple reflections and subsequent degradation in performance of two vertical reflective barriers; and (3) use of an artificial fixed?point source is not a viable test of barrier effectiveness.

Gregg G. Fleming; Edward J. Rickley

1991-01-01T23:59:59.000Z

297

Proton heating by parallel Alfven wave cascade  

SciTech Connect

In a recent series of papers, the present authors developed a kinetic theory for low-frequency turbulence propagating parallel to the ambient magnetic field. Making use of this theory, it was shown that low-frequency Alfvenic turbulence may cascade to ion-cyclotron frequency range and beyond by nonlinear three-wave decay processes. The significance of such a finding is that it may lead to the proton heating by cyclotron resonance. However, the actual proton heating process was not demonstrated. The present paper complements the previous works by including the proton heating in the discussion. It is found that the left-hand circularly polarized Alfven-cyclotron turbulence leads to a moderate heating of the protons in the perpendicular direction and cooling in the parallel direction. It is also found that ion-acoustic turbulence is generated by the decay instability process. Finally, the heating rate is shown to increase in inverse proportion to the time scale of the wave source.

Yoon, P. H.; Fang, T.-M. [Massachusetts Technological Laboratory, Inc., 330 Pleasant Street, Belmont, Massachusetts 02478 (United States)

2009-06-15T23:59:59.000Z

298

A Generate-Test-Aggregate parallel programming library for systematic parallel programming  

Science Journals Connector (OSTI)

The Generate-Test-Aggregate (GTA for short) algorithm is modeled following a simple and straightforward programming pattern, for combinatorial problems. First, generate all candidates; second, test and filter out invalid ones; finally, aggregate valid ... Keywords: Functional programming, Generate-Test-Aggregate algorithm, High-level parallel programming, MapReduce, Program calculation, Program transformation

Yu Liu; Kento Emoto; Zhenjiang Hu

2014-02-01T23:59:59.000Z

299

Sub-Second Parallel State Estimation  

SciTech Connect

This report describes the performance of Pacific Northwest National Laboratory (PNNL) sub-second parallel state estimation (PSE) tool using the utility data from the Bonneville Power Administrative (BPA) and discusses the benefits of the fast computational speed for power system applications. The test data were provided by BPA. They are two-days’ worth of hourly snapshots that include power system data and measurement sets in a commercial tool format. These data are extracted out from the commercial tool box and fed into the PSE tool. With the help of advanced solvers, the PSE tool is able to solve each BPA hourly state estimation problem within one second, which is more than 10 times faster than today’s commercial tool. This improved computational performance can help increase the reliability value of state estimation in many aspects: (1) the shorter the time required for execution of state estimation, the more time remains for operators to take appropriate actions, and/or to apply automatic or manual corrective control actions. This increases the chances of arresting or mitigating the impact of cascading failures; (2) the SE can be executed multiple times within time allowance. Therefore, the robustness of SE can be enhanced by repeating the execution of the SE with adaptive adjustments, including removing bad data and/or adjusting different initial conditions to compute a better estimate within the same time as a traditional state estimator’s single estimate. There are other benefits with the sub-second SE, such as that the PSE results can potentially be used in local and/or wide-area automatic corrective control actions that are currently dependent on raw measurements to minimize the impact of bad measurements, and provides opportunities to enhance the power grid reliability and efficiency. PSE also can enable other advanced tools that rely on SE outputs and could be used to further improve operators’ actions and automated controls to mitigate effects of severe events on the grid. The power grid continues to grow and the number of measurements is increasing at an accelerated rate due to the variety of smart grid devices being introduced. A parallel state estimation implementation will have better performance than traditional, sequential state estimation by utilizing the power of high performance computing (HPC). This increased performance positions parallel state estimators as valuable tools for operating the increasingly more complex power grid.

Chen, Yousu; Rice, Mark J.; Glaesemann, Kurt R.; Wang, Shaobu; Huang, Zhenyu

2014-10-31T23:59:59.000Z

300

SPRNG Parallel Random Number Generators at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

SPRNG SPRNG SPRNG Description The SPRNG libraries of generators produce good quality random numbers, and are also fast. They have been subjected to some of the largest random number tests, with around 10^13 RNs per test. SPRNG provides both FORTRAN and C (also C++) interfaces for the use of the parallel random number generators. Access SPRNG v2.0 is available on Carver (gcc, intel and pgi) and Cray systems (pgi and cce). Use the module utility to load the software. module load sprng Using SPRNG On Cray systems: ftn sprng_test.F $SPRNG -lsprng On Carver: mpif90 sprng_test.F $SPRNG -lsprng Documentation On Carver there are various documents in $SPRNG/DOCS and various examples in $SPRNG/EXAMPLES. See the SPRNG web site at Florida State University for complete details. For help using SPRNG at NERSC contact the

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


301

TotalView Parallel Debugger at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Totalview Totalview Totalview Description TotalView from Rogue Wave Software is a parallel debugging tool that can be run with up to 512 processors. It provides both X Windows-based Graphical User Interface (GUI) and command line interface (CLI) environments for debugging. The performance of the GUI can be greatly improved if used in conjunction with free NX software. The TotalView documentation web page is a good resource for learning more about some of the advanced TotalView features. Accessing Totalview at NERSC To use TotalView at NERSC, first load the TotalView modulefile to set the correct environment settings with the following command: % module load totalview Compiling Code to Run with TotalView In order to use TotalView, code must be compiled with the -g option. We

302

Clock Agreement Among Parallel Supercomputer Nodes  

SciTech Connect

This dataset presents measurements that quantify the clock synchronization time-agreement characteristics among several high performance computers including the current world's most powerful machine for open science, the U.S. Department of Energy's Titan machine sited at Oak Ridge National Laboratory. These ultra-fast machines derive much of their computational capability from extreme node counts (over 18000 nodes in the case of the Titan machine). Time-agreement is commonly utilized by parallel programming applications and tools, distributed programming application and tools, and system software. Our time-agreement measurements detail the degree of time variance between nodes and how that variance changes over time. The dataset includes empirical measurements and the accompanying spreadsheets.

Jones, Terry R.; Koenig, Gregory A.

2014-04-30T23:59:59.000Z

303

Clock Agreement Among Parallel Supercomputer Nodes  

DOE Data Explorer (OSTI)

This dataset presents measurements that quantify the clock synchronization time-agreement characteristics among several high performance computers including the current world's most powerful machine for open science, the U.S. Department of Energy's Titan machine sited at Oak Ridge National Laboratory. These ultra-fast machines derive much of their computational capability from extreme node counts (over 18000 nodes in the case of the Titan machine). Time-agreement is commonly utilized by parallel programming applications and tools, distributed programming application and tools, and system software. Our time-agreement measurements detail the degree of time variance between nodes and how that variance changes over time. The dataset includes empirical measurements and the accompanying spreadsheets.

Jones, Terry R.; Koenig, Gregory A.

304

The WFPC2 Archival Parallels Project  

E-Print Network (OSTI)

We describe the methods and procedures developed to obtain a near-automatic combination of WFPC2 images obtained as part of the WFPC2 Archival Pure Parallels program. Several techniques have been developed or refined to ensure proper alignment, registration, and combination of overlapping images that can be obtained at different times and with different orientations. We quantify the success rate and the accuracy of the registration of images of different types, and we develop techniques suitable to equalize the sky background without unduly affecting extended emission. About 600 combined images of the 1,500 eventually planned have already been publicly released through the STScI Archive. The images released to date are especially suited to study star formation in the Magellanic Clouds, the stellar population in the halo of nearby galaxies, and the properties of star-forming galaxies at $ z \\sim 3 $.

Yogesh Wadadekar; Stefano Casertano; Richard Hook; Bül ent K?z?ltan; Anton Koekemoer; Harry Ferguson; Doichin Denchev

2005-11-08T23:59:59.000Z

305

Broadcasting a message in a parallel computer  

DOE Patents (OSTI)

Methods, systems, and products are disclosed for broadcasting a message in a parallel computer that includes: transmitting, by the logical root to all of the nodes directly connected to the logical root, a message; and for each node except the logical root: receiving the message; if that node is the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received; if that node received the message from a parent node and if that node is not a leaf node, then transmitting the message to all of the child nodes; and if that node received the message from a child node and if that node is not the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received and transmitting the message to the parent node.

Archer, Charles J; Faraj, Ahmad A

2013-04-16T23:59:59.000Z

306

Broadcasting a message in a parallel computer  

DOE Patents (OSTI)

Methods, systems, and products are disclosed for broadcasting a message in a parallel computer that includes: transmitting, by the logical root to all of the nodes directly connected to the logical root, a message; and for each node except the logical root: receiving the message; if that node is the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received; if that node received the message from a parent node and if that node is not a leaf node, then transmitting the message to all of the child nodes; and if that node received the message from a child node and if that node is not the physical root, then transmitting the message to all of the child nodes except the child node from which the message was received and transmitting the message to the parent node.

Archer, Charles J; Faraj, Daniel A

2014-11-18T23:59:59.000Z

307

Optimized data communications in a parallel computer  

SciTech Connect

A parallel computer includes nodes that include a network adapter that couples the node in a point-to-point network and supports communications in opposite directions of each dimension. Optimized communications include: receiving, by a network adapter of a receiving compute node, a packet--from a source direction--that specifies a destination node and deposit hints. Each hint is associated with a direction within which the packet is to be deposited. If a hint indicates the packet to be deposited in the opposite direction: the adapter delivers the packet to an application on the receiving node; forwards the packet to a next node in the opposite direction if the receiving node is not the destination; and forwards the packet to a node in a direction of a subsequent dimension if the hints indicate that the packet is to be deposited in the direction of the subsequent dimension.

Faraj, Daniel A

2014-10-21T23:59:59.000Z

308

Optimized data communications in a parallel computer  

SciTech Connect

A parallel computer includes nodes that include a network adapter that couples the node in a point-to-point network and supports communications in opposite directions of each dimension. Optimized communications include: receiving, by a network adapter of a receiving compute node, a packet--from a source direction--that specifies a destination node and deposit hints. Each hint is associated with a direction within which the packet is to be deposited. If a hint indicates the packet to be deposited in the opposite direction: the adapter delivers the packet to an application on the receiving node; forwards the packet to a next node in the opposite direction if the receiving node is not the destination; and forwards the packet to a node in a direction of a subsequent dimension if the hints indicate that the packet is to be deposited in the direction of the subsequent dimension.

Faraj, Daniel A.

2014-08-19T23:59:59.000Z

309

Optimising Shewhart charts in parallel production lines  

Science Journals Connector (OSTI)

I describe a methodology for optimising n Shewhart x-charts operating on parallel production lines in a factory. The goal is to maximise the factory-wide probability of detecting an out-of-control condition subject to a constraint on the expected number of false signals. I use non-linear programming to appropriately set the x-charts' control limits incorporating information about the probability of each production line going out-of-control. Using this approach, factories can set their quality control systems to optimally detect out-of-control conditions. Given some distributional assumptions, I also present a one-dimensional optimisation methodology that allows for the efficient optimisation of very large factories.

Ronald D. Fricker; Jr."> Jr.

2009-01-01T23:59:59.000Z

310

Internode data communications in a parallel computer  

DOE Patents (OSTI)

Internode data communications in a parallel computer that includes compute nodes that each include main memory and a messaging unit, the messaging unit including computer memory and coupling compute nodes for data communications, in which, for each compute node at compute node boot time: a messaging unit allocates, in the messaging unit's computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; receives, prior to initialization of a particular process on the compute node, a data communications message intended for the particular process; and stores the data communications message in the message buffer associated with the particular process. Upon initialization of the particular process, the process establishes a messaging buffer in main memory of the compute node and copies the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

Archer, Charles J.; Blocksome, Michael A.; Miller, Douglas R.; Parker, Jeffrey J.; Ratterman, Joseph D.; Smith, Brian E.

2013-09-03T23:59:59.000Z

311

Intranode data communications in a parallel computer  

DOE Patents (OSTI)

Intranode data communications in a parallel computer that includes compute nodes configured to execute processes, where the data communications include: allocating, upon initialization of a first process of a computer node, a region of shared memory; establishing, by the first process, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; sending, to a second process on the same compute node, a data communications message without determining whether the second process has been initialized, including storing the data communications message in the message buffer of the second process; and upon initialization of the second process: retrieving, by the second process, a pointer to the second process's message buffer; and retrieving, by the second process from the second process's message buffer in dependence upon the pointer, the data communications message sent by the first process.

Archer, Charles J; Blocksome, Michael A; Miller, Douglas R; Ratterman, Joseph D; Smith, Brian E

2014-01-07T23:59:59.000Z

312

Intranode data communications in a parallel computer  

DOE Patents (OSTI)

Intranode data communications in a parallel computer that includes compute nodes configured to execute processes, where the data communications include: allocating, upon initialization of a first process of a compute node, a region of shared memory; establishing, by the first process, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; sending, to a second process on the same compute node, a data communications message without determining whether the second process has been initialized, including storing the data communications message in the message buffer of the second process; and upon initialization of the second process: retrieving, by the second process, a pointer to the second process's message buffer; and retrieving, by the second process from the second process's message buffer in dependence upon the pointer, the data communications message sent by the first process.

Archer, Charles J; Blocksome, Michael A; Miller, Douglas R; Ratterman, Joseph D; Smith, Brian E

2013-07-23T23:59:59.000Z

313

Internode data communications in a parallel computer  

DOE Patents (OSTI)

Internode data communications in a parallel computer that includes compute nodes that each include main memory and a messaging unit, the messaging unit including computer memory and coupling compute nodes for data communications, in which, for each compute node at compute node boot time: a messaging unit allocates, in the messaging unit's computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; receives, prior to initialization of a particular process on the compute node, a data communications message intended for the particular process; and stores the data communications message in the message buffer associated with the particular process. Upon initialization of the particular process, the process establishes a messaging buffer in main memory of the compute node and copies the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

Archer, Charles J; Blocksome, Michael A; Miller, Douglas R; Parker, Jeffrey J; Ratterman, Joseph D; Smith, Brian E

2014-02-11T23:59:59.000Z

314

Application of a parallel DSMC method to hypersonic rarefied flows  

SciTech Connect

This paper describes a method for doing direct simulation Monte Carlo (DSMC) calculations using parallel processing and presents some results of applying the method to several hypersonic, rarefied flow problems. The performance and efficiency of the parallel method are discussed. The applications described are the flow in a channel and the flow about a flat plate at incidence. The results show significant advantages of parallel processing over conventional scalar processing and demonstrate the scalability of the method to large problems. 8 refs.

Wilmoth, R.G. (NASA, Langley Research Center, Hampton, VA (USA))

1991-01-01T23:59:59.000Z

315

Compiler integration of speculative run time parallelization techniques  

E-Print Network (OSTI)

pattern (array subscripts in the case of Fortran programs) and on parallelism enabling transformations like privatization, reduction paraHelization, induction variable substitution, etc. [16]. As mentioned in Section I, when static information... in parallel if and only if its later iterations do not use data computed in its earlier iterations, i. e. , there are no fiow dependences. The safety of this and other related transformations (e. g. , privatization, reduction parallelization) is checked...

Patel, Devangkumar Rameshbhai

2012-06-07T23:59:59.000Z

316

Holographic Polarons, the Metal-Insulator Transition and Massive Gravity  

E-Print Network (OSTI)

Massive gravity is holographically dual to `realistic' materials with momentum relaxation. The dual graviton potential encodes the phonon dynamics and it allows for a much broader diversity than considered so far. We construct a simple family of isotropic and homogeneous materials that exhibit an interaction-driven Metal-Insulator transition. The transition is triggered by the formation of polarons -- phonon-electron quasi-bound states that dominate the conductivities, shifting the spectral weight above a mass gap. We characterize the polaron gap, width and dispersion.

Baggioli, Matteo

2014-01-01T23:59:59.000Z

317

Holographic Polarons, the Metal-Insulator Transition and Massive Gravity  

E-Print Network (OSTI)

Massive gravity is holographically dual to `realistic' materials with momentum relaxation. The dual graviton potential encodes the phonon dynamics and it allows for a much broader diversity than considered so far. We construct a simple family of isotropic and homogeneous materials that exhibit an interaction-driven Metal-Insulator transition. The transition is triggered by the formation of polarons -- phonon-electron quasi-bound states that dominate the conductivities, shifting the spectral weight above a mass gap. We characterize the polaron gap, width and dispersion.

Matteo Baggioli; Oriol Pujolas

2014-11-04T23:59:59.000Z

318

Anisotropic massive strings in scalar-tensor theory of gravitation  

E-Print Network (OSTI)

We present the model of anisotropic universe with string fluid as source of matter within the framework of scalar-tensor theory of gravitation. Exact solution of field equations are obtained by applying Berman's law of variation of Hubble's parameter which yields a constant value of DP. The nature of classical potential is examined for the model under consideration. It has been also found that the massive strings dominate in early universe and at long last disappear from universe. This is in agreement with current astronomical observations. The physical and dynamical properties of model are also discussed.

Anil Kumar Yadav

2012-11-15T23:59:59.000Z

319

Solar-like oscillations in a massive star  

E-Print Network (OSTI)

Seismology of stars provides insight into the physical mechanisms taking place in their interior, with modes of oscillation probing different layers. Low-amplitude acoustic oscillations excited by turbulent convection were detected four decades ago in the Sun and more recently in low-mass main-sequence stars. Using data gathered by the Convection Rotation and Planetary Transits mission, we report here on the detection of solar-like oscillations in a massive star, V1449 Aql, which is a known large-amplitude (b Cephei) pulsator.

Belkacem, K; Goupil, M -J; Lefèvre, L; Baudin, F; Deheuvels, S; Dupret, M -A; Appourchaux, T; Scuflaire, R; Auvergne, M; Catala, C; Michel, E; Miglio, A; Montalban, J; Thoul, A; Talon, S; Baglin, A; Noels, A

2009-01-01T23:59:59.000Z

320

Neutrino Tomography of Gamma Ray Bursts and Massive Stellar Collapses  

E-Print Network (OSTI)

Neutrinos at energies above TeV can serve as probes of the stellar progenitor and jet dynamics of gamma ray bursts arising from stellar core collapses. They can also probe collapses which do not lead to gamma-rays, which may be much more numerous. We calculate detailed neutrino spectra from shock accelerated protons in jets just below the outer stellar envelope, before their emergence. We present neutrino flux estimates from such pre-burst jets for two different massive stellar progenitor models. These should be distinguishable by IceCube, and we discuss the implications.

Soebur Razzaque; Peter Meszaros; Eli Waxman

2003-03-21T23:59:59.000Z

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


321

Massive zero-metal stars: Energy production and mixing  

E-Print Network (OSTI)

Time-dependent nuclear network calculations at constant temperature show that for zero-metal stars >= 20 Msun (i) beta-decay reactions and (ii) the 13N(p,gamma)14O reaction must be included. It is also shown that the nuclear timescale in these zero-metal stars is shorter than the mixing timescale and therefore the assumption of instantaneous mixing across convective regions is not fulfilled. We conclude that proper modeling of these processes may alter the evolution of massive zero-metal stars.

C. W. Straka; W. M. Tscharnuter

2001-03-21T23:59:59.000Z

322

pMatlab Parallel Matlab Library  

E-Print Network (OSTI)

MATLAB has emerged as one of the languages most commonly used by scientists and engineers for technical computing, with ~1,000,000 users worldwide. The compute intensive nature of technical computing means that many MATLAB users have codes that can significantly benefit from the increased performance offered by parallel computing. pMatlab (www.ll.mit.edu/pMatlab) provides this capability by implementing Parallel Global Array Semantics (PGAS) using standard operator overloading techniques. The core data structure in pMatlab is a distributed numerical array whose distribution onto multiple processors is specified with a map construct. Communication operations between distributed arrays are abstracted away from the user and pMatlab transparently supports redistribution between any block-cyclic-overlapped distributions up to four dimensions. pMatlab is built on top of the MatlabMPI communication library (www.ll.mit.edu/MatlabMPI) and runs on any combination of heterogeneous systems that support MATLAB, which includes Windows, Linux, MacOSX, and SunOS. Performance is validated by implementing the HPC Challenge benchmark suite and comparing pMatlab performance with the equivalent C+MPI codes. These results indicate that pMatlab can often achieve comparable performance to C+MPI at usually 1/10th the code size. Finally, we present implementation data collected from a sample of 10 real pMatlab applications drawn from the ~100 users at MIT Lincoln Laboratory. These data indicate that users are typically able to go from a serial code to a well performing pMatlab code in about 3 hours while changing less than 1% of their code.

Nadya Bliss; Jeremy Kepner

2006-06-20T23:59:59.000Z

323

A Parallel Line Search Subspace Correction Method for Composite ...  

E-Print Network (OSTI)

Oct 7, 2014 ... Abstract: In this paper, we investigate a parallel subspace correction framework for composite convex optimization. The variables are first ...

Qian Dong

2014-10-07T23:59:59.000Z

324

A parallel between two classes of pricing problems in transportation ...  

E-Print Network (OSTI)

Jan 5, 2009 ... A parallel between two classes of pricing problems in transportation and economics. G raldine Heilporn (Geraldine.Heilporn ***at*** hec.ca)

G raldine Heilporn

2009-01-05T23:59:59.000Z

325

An Exact Extended Formulation for the Unrelated Parallel Machine ...  

E-Print Network (OSTI)

Aug 28, 2014 ... Abstract: The plethora of research on NP-hard parallel machine scheduling problems is focused on heuristics due to the theoretically and ...

Kerem Bulbul

2014-08-28T23:59:59.000Z

326

Parallel machine match-up scheduling with manufacturing cost considerations  

E-Print Network (OSTI)

approach for the single machine scheduling problem. Journaldecisions on parallel CNC machines: -constraint approach.mechanism for the CNC machine scheduling problems with

Aktürk, M. Selim; Atamtürk, Alper; Gürel, Sinan

2010-01-01T23:59:59.000Z

327

Parallel machine match-up scheduling with manufacturing cost considerations  

E-Print Network (OSTI)

decisions on parallel CNC machines: -constraint approach.bounding mechanism for the CNC machine scheduling problemsprocessing times is the CNC turning operation where

Aktürk, M. Selim; Atamtürk, Alper; Gürel, Sinan

2010-01-01T23:59:59.000Z

328

Derivation of parallel algorithms from functional specifications to CSP processes  

Science Journals Connector (OSTI)

A transformational programming approach is proposed as a means for developing a class of parallel algorithms from clear functional specifications to efficient networks of communicating sequential processes (CSP)....

Ali E. Abdallah

1995-01-01T23:59:59.000Z

329

Minimax design of parallel multi-mass dynamic vibration absorbers.  

E-Print Network (OSTI)

?? This thesis discusses the design of multi-mass dynamic vibration absorbers in parallel configuration subject to uncertainties in the forcing frequency. A minimax parameter optimization… (more)

Kee, Kerk Cheng

2011-01-01T23:59:59.000Z

330

Hybrid Parallelism for Volume Rendering at Large Scale at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Volume Rendering at Large Scale Hybrid Parallelism for Volume Rendering at Large Scale volrend-swes.png We studied the performance and scalability characteristics of hybrid''...

331

Exponential neighborhood search for a parallel machine scheduling ...  

E-Print Network (OSTI)

Sun and Wang [26] consider the identical parallel machine problem with a large ...... be found in the OR-Library which is a collection of instances for operations ...

2006-08-09T23:59:59.000Z

332

Fencing direct memory access data transfers in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Fencing direct memory access (`DMA`) data transfers in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI including data communications endpoints, each endpoint including specifications of a client, a context, and a task, the endpoints coupled for data communications through the PAMI and through DMA controllers operatively coupled to segments of shared random access memory through which the DMA controllers deliver data communications deterministically, including initiating execution through the PAMI of an ordered sequence of active DMA instructions for DMA data transfers between two endpoints, effecting deterministic DMA data transfers through a DMA controller and a segment of shared memory; and executing through the PAMI, with no FENCE accounting for DMA data transfers, an active FENCE instruction, the FENCE instruction completing execution only after completion of all DMA instructions initiated prior to execution of the FENCE instruction for DMA data transfers between the two endpoints.

Blocksome, Michael A.; Mamidala, Amith R.

2013-09-03T23:59:59.000Z

333

Data communications in a parallel active messaging interface of a parallel computer  

SciTech Connect

Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and ranges of message sizes so that each algorithm is associated with a separate range of message sizes; receiving in an origin endpoint of the PAMI a data communications instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint, the data communications message characterized by a message size; selecting, from among the associated algorithms and ranges, a data communications algorithm in dependence upon the message size; and transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

Davis, Kristan D.; Faraj, Daniel A.

2014-07-22T23:59:59.000Z

334

Fencing direct memory access data transfers in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Fencing direct memory access (`DMA`) data transfers in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI including data communications endpoints, each endpoint including specifications of a client, a context, and a task, the endpoints coupled for data communications through the PAMI and through DMA controllers operatively coupled to segments of shared random access memory through which the DMA controllers deliver data communications deterministically, including initiating execution through the PAMI of an ordered sequence of active DMA instructions for DMA data transfers between two endpoints, effecting deterministic DMA data transfers through a DMA controller and a segment of shared memory; and executing through the PAMI, with no FENCE accounting for DMA data transfers, an active FENCE instruction, the FENCE instruction completing execution only after completion of all DMA instructions initiated prior to execution of the FENCE instruction for DMA data transfers between the two endpoints.

Blocksome, Michael A; Mamidala, Amith R

2014-02-11T23:59:59.000Z

335

Data communications in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Eager send data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints that specify a client, a context, and a task, including receiving an eager send data communications instruction with transfer data disposed in a send buffer characterized by a read/write send buffer memory address in a read/write virtual address space of the origin endpoint; determining for the send buffer a read-only send buffer memory address in a read-only virtual address space, the read-only virtual address space shared by both the origin endpoint and the target endpoint, with all frames of physical memory mapped to pages of virtual memory in the read-only virtual address space; and communicating by the origin endpoint to the target endpoint an eager send message header that includes the read-only send buffer memory address.

Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

2014-09-16T23:59:59.000Z

336

Data communications in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Eager send data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints that specify a client, a context, and a task, including receiving an eager send data communications instruction with transfer data disposed in a send buffer characterized by a read/write send buffer memory address in a read/write virtual address space of the origin endpoint; determining for the send buffer a read-only send buffer memory address in a read-only virtual address space, the read-only virtual address space shared by both the origin endpoint and the target endpoint, with all frames of physical memory mapped to pages of virtual memory in the read-only virtual address space; and communicating by the origin endpoint to the target endpoint an eager send message header that includes the read-only send buffer memory address.

Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

2014-09-02T23:59:59.000Z

337

Data communications in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI and through data communications resources, including receiving in an origin endpoint of the PAMI a SEND instruction, the SEND instruction specifying a transmission of transfer data from the origin endpoint to a first target endpoint; transmitting from the origin endpoint to the first target endpoint a Request-To-Send (`RTS`) message advising the first target endpoint of the location and size of the transfer data; assigning by the first target endpoint to each of a plurality of target endpoints separate portions of the transfer data; and receiving by the plurality of target endpoints the transfer data.

Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

2014-11-18T23:59:59.000Z

338

Holonomies of gauge fields in twistor space 6: incorporation of massive fermions  

E-Print Network (OSTI)

Following the previous paper arXiv:1205.4827, we formulate an S-matrix functional for massive fermion ultra-helicity-violating (UHV) amplitudes, i.e., scattering amplitudes of positive-helicity gluons and a pair of massive fermions. The S-matrix functional realizes a massive extension of the Cachazo-Svrcek-Witten (CSW) rules in a functional language. Mass-dimension analysis implies that interactions among gluons and massive fermions should be decomposed into three-point massive fermion subamplitudes. Namely, such interactions are represented by combinations of three-point UHV and next-to-UHV (NUHV) vertices. This feature is qualitatively different from the massive scalar amplitudes where the number of involving gluons can be arbitrary.

Yasuhiro Abe

2013-11-13T23:59:59.000Z

339

Efficient Algorithms for Parallel Excitation and Parallel Imaging with Large Arrays  

E-Print Network (OSTI)

1.3 32 channel lattice transmission line array [1] . . . . . . . . . . . . . . 3 1.4 The 64 channel tranceive array built in MRSL, TAMU . . . . . . . . 3 2.1 Larmor frequency and signal formation . . . . . . . . . . . . . . . . . 7 2.2 Constant... array also increase the degree of freedom of parallel excita- tion pulse design and provides improved performance. Transmit array examples are shown in Fig. 1.3 and Fig. 1.4. Figure 1.3: 32 channel lattice transmission line array [1] Figure 1...

Feng, Shuo

2013-08-12T23:59:59.000Z

340

Discovery of a Massive Protostar near IRAS 18507+0121  

E-Print Network (OSTI)

We have observed the massive star forming region, IRAS 18507+0121, at millimeter wavelengths in 3 mm continuum emission and H13CO+(J=1-0) and SiO(v=0, J=2-1) line emission, and at near-infrared wavelengths between 1.2 and 2.1 microns. Two compact molecular cores are detected: one north and one south separated by about 40". The northern molecular core contains a newly discovered, deeply embedded, B2 protostar surrounded by several hundred solar masses of warm gas and dust, G34.4+0.23 MM. Based on the presence of warm dust emission and the lack of detection at near-infrared wavelengths, we suggest that G34.4+0.23 MM may represent the relatively rare discovery of a massive protostar (e.g. analogous to a low-mass "Class 0" protostar). The southern molecular core is associated with a near-infrared cluster of young stars and an ultracompact (UC) HII region, G34.4+0.23, with a central B0.5 star. The fraction of near-infrared stars with excess infrared emission indicative of circumstellar material is greater than 50% which suggests an upper limit on the age of the IRAS 18507+0121 star forming region of 3 Myrs.

D. S. Shepherd; D. E. A. Nurnberger; L. Bronfman

2003-10-27T23:59:59.000Z

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


341

Nanoscale Cluster Detection in Massive Atom Probe Tomography Data  

SciTech Connect

Recent technological advances in atom probe tomography (APT) have led to unprecedented data acquisition capabilities that routinely generate data sets containing hundreds of millions of atoms. Detecting nanoscale clusters of different atom types present in these enormous amounts of data and analyzing their spatial correlations with one another are fundamental to understanding the structural properties of the material from which the data is derived. Extant algorithms for nanoscale cluster detection do not scale to large data sets. Here, a scalable, CUDA-based implementation of an autocorrelation algorithm is presented. It isolates spatial correlations amongst atomic clusters present in massive APT data sets in linear time using a linear amount of storage. Correctness of the algorithm is demonstrated using large synthetically generated data with known spatial distributions. Benefits and limitations of using GPU-acceleration for autocorrelation-based APT data analyses are presented with supporting performance results on data sets with up to billions of atoms. To our knowledge, this is the first nanoscale cluster detection algorithm that scales to massive APT data sets and executes on commodity hardware.

Seal, Sudip K [ORNL] [ORNL; Yoginath, Srikanth B [ORNL] [ORNL; Miller, Michael K [ORNL] [ORNL

2014-01-01T23:59:59.000Z

342

Gyrokinetic Toroidal Code: a 3D Parallel Particle-in-Cell Code to Study Microturbulence in Magnetized Plasmas  

NLE Websites -- All DOE Office Websites (Extended Search)

benchmarking and benchmarking and optimizing GTC on High Performance Computers Stéphane Ethier Princeton Plasma Physics Laboratory NERSC Users' Group meeting June 2006 Work Supported by DOE Contract No.DE-AC02-76CH03073 and by the DOE SciDAC Center for Gyrokinetic Particle Simulation of Turbulent Transport in Burning Plasmas. The Gyrokinetic Toroidal Code * 3D particle-in-cell code to study microturbulence in magnetically confined fusion plasmas. * Solves the gyro-averaged Vlasov equation. * Gyrokinetic Poisson equation solved in real space. * Low noise δf method. * Global code (full torus as opposed to only a flux tube). * Massively parallel: typical runs done on 1024 processors. * Electrostatic approximation with adiabatic electrons. * Nonlinear and fully self-consistent. * Written in Fortran 90/95

343

Programming for Locality and Parallelism with Hierarchically Tiled ArraysJuly 13, 2003 1 Programming for Locality and Parallelism with  

E-Print Network (OSTI)

- guages, Co-Array Fortran [NuRe98] and Unified Parallel C (UPC) [CDCY99]. Our pro- posal follows these two

Padua, David

344

Current parallel I/O limitations to scalable data analysis.  

SciTech Connect

This report describes the limitations to parallel scalability which we have encountered when applying our otherwise optimally scalable parallel statistical analysis tool kit to large data sets distributed across the parallel file system of the current premier DOE computational facility. This report describes our study to evaluate the effect of parallel I/O on the overall scalability of a parallel data analysis pipeline using our scalable parallel statistics tool kit [PTBM11]. In this goal, we tested it using the Jaguar-pf DOE/ORNL peta-scale platform on a large combustion simulation data under a variety of process counts and domain decompositions scenarios. In this report we have recalled the foundations of the parallel statistical analysis tool kit which we have designed and implemented, with the specific double intent of reproducing typical data analysis workflows, and achieving optimal design for scalable parallel implementations. We have briefly reviewed those earlier results and publications which allow us to conclude that we have achieved both goals. However, in this report we have further established that, when used in conjuction with a state-of-the-art parallel I/O system, as can be found on the premier DOE peta-scale platform, the scaling properties of the overall analysis pipeline comprising parallel data access routines degrade rapidly. This finding is problematic and must be addressed if peta-scale data analysis is to be made scalable, or even possible. In order to attempt to address these parallel I/O limitations, we will investigate the use the Adaptable IO System (ADIOS) [LZL+10] to improve I/O performance, while maintaining flexibility for a variety of IO options, such MPI IO, POSIX IO. This system is developed at ORNL and other collaborating institutions, and is being tested extensively on Jaguar-pf. Simulation code being developed on these systems will also use ADIOS to output the data thereby making it easier for other systems, such as ours, to process that data.

Mascarenhas, Ajith Arthur; Pebay, Philippe Pierre

2011-07-01T23:59:59.000Z

345

Tholeiitic basalt–rhyolite magmatism and massive sulphide deposits at Matagami, Quebec  

Science Journals Connector (OSTI)

... exploration targets. However, in one of these large Archean volcanic centres, at Matagami, Quebec, this relationship does not hold; the massive sulphide deposits, while originally thought to ...

P. J. MacGeehan; W. H. MacLean

1980-01-10T23:59:59.000Z

346

Constraints on the Structure, Evolution, and Approach to Thermonuclear Runaway in Intermediate Mass and Massive Stars.  

E-Print Network (OSTI)

??This thesis provides an assessment of stellar evolution models for intermediate-mass and massive stars in advanced stages of evolution through a detailed cooperation between simulations… (more)

Dolan, Michelle Marie

2013-01-01T23:59:59.000Z

347

Massive Energy Storage in Superconductors (SMES) | U.S. DOE Office...  

Office of Science (SC) Website

Massive Energy Storage in Superconductors (SMES) High Energy Physics (HEP) HEP Home About Research Facilities Science Highlights Benefits of HEP Funding Opportunities Advisory...

348

Data Reduction Enables Massive Data Handling in Super-resolution Localization Microscopy  

Science Journals Connector (OSTI)

Massive data handling is the major challenge in super-resolution localization microscopy. Here we present a data reduction approach to solve this challenge. This approach enables the...

Ma, Hongqiang; Zeng, Shaoqun; Huang, Zhen-li

349

Endpoint-based parallel data processing with non-blocking collective instructions in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Methods, apparatuses, and computer program products for endpoint-based parallel data processing with non-blocking collective instructions in a parallel active messaging interface (`PAMI`) of a parallel computer are provided. Embodiments include establishing by a parallel application a data communications geometry, the geometry specifying a set of endpoints that are used in collective operations of the PAMI, including associating with the geometry a list of collective algorithms valid for use with the endpoints of the geometry. Embodiments also include registering in each endpoint in the geometry a dispatch callback function for a collective operation and executing without blocking, through a single one of the endpoints in the geometry, an instruction for the collective operation.

Archer, Charles J; Blocksome, Michael A; Cernohous, Bob R; Ratterman, Joseph D; Smith, Brian E

2014-11-18T23:59:59.000Z

350

Automatic Parallelization of Hand Written Automotive Engine Control  

E-Print Network (OSTI)

Automatic Parallelization of Hand Written Automotive Engine Control Codes Using OSCAR Compiler Dan approach to realize the next- generation automobiles integrated control system. However, automotive-core processors for a long time. This paper proposes to parallelize an automotive engine crankshaft control

Kasahara, Hironori

351

The data diffusion space for parallel computing in clusters  

Science Journals Connector (OSTI)

The data diffusion space (DDS) is an all-software shared address space for parallel computing on distributed memory platforms. It is an extra address space to that of each process running a parallel application under the SPMD (Single Program Multiple ...

Jorge Buenabad-Chávez; Santiago Domínguez-Domínguez

2005-08-01T23:59:59.000Z

352

SCCMulti: an improved parallel strongly connected components algorithm  

Science Journals Connector (OSTI)

Tarjan's famous linear time, sequential algorithm for finding the strongly connected components (SCCs) of a graph relies on depth first search, which is inherently sequential. Deterministic parallel algorithms solve this problem in logarithmic time using ... Keywords: parallel graph algorithms, randomized algorithms, strongly connected components

Daniel Tomkins; Timmie Smith; Nancy M. Amato; Lawrence Rauchwerger

2014-02-01T23:59:59.000Z

353

Parallel MATLAB: Doing it Right Ron Choy , Alan Edelman  

E-Print Network (OSTI)

1 Parallel MATLAB: Doing it Right Ron Choy , Alan Edelman Computer Science AI Laboratory-MIT Alliance November 15, 2003 DRAFT #12;2 Abstract MATLAB [20] is one of the most widely used mathematical Moler of Mathworks argued that there was no market at the time for a parallel MATLAB [26]. But times

Edelman, Alan

354

Spatial Computing as Intensional Data Parallelism Antoine Spicher, Olivier Michel  

E-Print Network (OSTI)

Spatial Computing as Intensional Data Parallelism Antoine Spicher, Olivier Michel LACL Universit to illustrate this statement. Keywords-spatial computing, collection, data-fields, data flow, declarative definition, intensionnal programming, stream, data parallelism I. SPATIAL COMPUTING It is customary to make

Paris-Sud XI, Université de

355

On the Interplay of Parallelization, Program Performance, and Energy Consumption  

E-Print Network (OSTI)

to either minimize the total energy consumption or minimize the energy-delay product. The impact of staticOn the Interplay of Parallelization, Program Performance, and Energy Consumption Sangyeun Cho through parallel execution of applications, suppressing the power and energy consumption remains an even

Marchal, Loris

356

GPU-based parallelization for fast circuit optimization  

Science Journals Connector (OSTI)

The progress of GPU (Graphics Processing Unit) technology opens a new avenue for boosting computing power. This work is an attempt to exploit GPU for accelerating VLSI circuit optimization. We propose GPU-based parallel computing techniques and apply ... Keywords: GPU, VLSI circuit optimization, parallel computing

Yifang Liu; Jiang Hu

2009-07-01T23:59:59.000Z

357

Parallel Training of An Improved Neural Network for Text Categorization  

Science Journals Connector (OSTI)

This paper studies parallel training of an improved neural network for text categorization. With the explosive growth on the amount of digital information available on the Internet, text categorization problem has become more and more important, especially ... Keywords: Neural networks, Parallel computing, Text categorization

Cheng Hua Li, Laurence T. Yang, Man Lin

2014-06-01T23:59:59.000Z

358

IPSJ SIG Technical Report Automatic parallelization with OSCAR API Analyzer  

E-Print Network (OSTI)

IPSJ SIG Technical Report Automatic parallelization with OSCAR API Analyzer: a cross have devel- oped the OSCAR API Analyzer. It allows programs automatically parallelized by the OSCAR compiler with OSCAR API directives to target many different platforms using just sequential compilers. We

Kasahara, Hironori

359

Parallel Imaging and Acceleration in the Johnson Noise Dominated Regime  

E-Print Network (OSTI)

Parallel Imaging and Acceleration in the Johnson Noise Dominated Regime Cristen D. LaPierre1 receive coil in the parallel array. At low field, uncorrelated Johnson noise dominates, providing in the Johnson noise dominated regime. With the eight channel array, SENSE acceleration can be implemented

Rosen, Matthew S

360

Parallel Picoliter RT-PCR Assays Using Microfluidics  

E-Print Network (OSTI)

Parallel Picoliter RT-PCR Assays Using Microfluidics Joshua S. Marcus,, W. French Anderson The development of microfluidic tools for high-throughput nucleic acid analysis has become a burgeoning area of research in the post-genome era. Here, we have developed a microfluidic chip to perform 72 parallel 450-p

Quake, Stephen R.

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


361

A provably time-efficient parallel implementation of full speculation  

Science Journals Connector (OSTI)

Speculative evaluation, including leniency and futures, is often used to produce high degrees of parallelism. Understanding the performance characteristics of such evaluation, however, requires having a detailed understanding of the implementation. For ... Keywords: abstract machines, parallel languages, profiling semantics, speculation, threads

John Greiner; Guy E. Blelloch

1999-03-01T23:59:59.000Z

362

Mono inverter Multi parallel PMSM -Structure and Control strategy  

E-Print Network (OSTI)

a new and original Mono inverter Multi parallel Permanent Magnet Synchronous Motor (PMSM) systemMono inverter Multi parallel PMSM - Structure and Control strategy Damien Bidarta , Maria Pietrzak, braking system...). However, a MMS with machines operating independently needs a high number of power

Boyer, Edmond

363

Parallel Finite Element Simulation of Tracer Injection in Oil Reservoirs  

E-Print Network (OSTI)

Parallel Finite Element Simulation of Tracer Injection in Oil Reservoirs Alvaro L.G.A. Coutinho In this work, parallel finite element techniques for the simulation of tracer injection in oil reservoirs. Supercomputers have made it possible to consider global reservoir effects which can not be represented using

Coutinho, Alvaro L. G. A.

364

Parallel Processing Letters fc World Scientific Publishing Company  

E-Print Network (OSTI)

that occurred on a production site of EGEE and the troubleshooting process for each case. Finally, we proposeParallel Processing Letters fc World Scientific Publishing Company FAILURE MANAGEMENT IN GRIDS infrastructure [1] in the context #12;Parallel Processing Letters of a drug-design effort [12], indicate

Pallis, George

365

The Manycore Revolution and Parallel Software Projects at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

The Manycore The Manycore Revolution and Parallel Software The Manycore Revolution and Parallel Software | Tags: Math & Computer Science PGAS.jpg Key Challenges: A new software ecosystem is expected to emerge over the next decade to support changes brought about by manycore and multicore systems. The question is whether languages like Unified Parallel C (UPC), which runs on all of the major DOE Office of Science platforms, can provide the best path forward, lowering the barrier to entry for parallel computing and making parallel machines more attractive as commercial products. Why it Matters: Although MPI is currently the de facto standard for programming supercomputers, partitioned global address space (PGAS) languages offer advantages in both programmability and performance. They

366

Load Balancing Of Parallel Monte Carlo Transport Calculations  

National Nuclear Security Administration (NNSA)

Load Balancing Of Parallel Load Balancing Of Parallel Monte Carlo Transport Calculations R.J. Procassini, M. J. O'Brien and J.M. Taylor Lawrence Livermore National Laboratory, P. O. Box 808, Livermore, CA 94551 The performance of parallel Monte Carlo transport calculations which use both spatial and particle parallelism is increased by dynamically assigning processors to the most worked domains. Since the particle work load varies over the course of the simulation, each cycle this algorithm determines if dynamic load balancing would speed up the calculation. If load balancing is required, a small number of particle communications are initiated in order to achieve load balance. This method has decreased the parallel run time by more than a factor of three for certain criticality

367

Broadcasting collective operation contributions throughout a parallel computer  

DOE Patents (OSTI)

Methods, systems, and products are disclosed for broadcasting collective operation contributions throughout a parallel computer. The parallel computer includes a plurality of compute nodes connected together through a data communications network. Each compute node has a plurality of processors for use in collective parallel operations on the parallel computer. Broadcasting collective operation contributions throughout a parallel computer according to embodiments of the present invention includes: transmitting, by each processor on each compute node, that processor's collective operation contribution to the other processors on that compute node using intra-node communications; and transmitting on a designated network link, by each processor on each compute node according to a serial processor transmission sequence, that processor's collective operation contribution to the other processors on the other compute nodes using inter-node communications.

Faraj, Ahmad (Rochester, MN)

2012-02-21T23:59:59.000Z

368

Transparent runtime parallelization of the R scripting language  

SciTech Connect

Scripting languages such as R and Matlab are widely used in scientific data processing. As the data volume and the complexity of analysis tasks both grow, sequential data processing using these tools often becomes the bottleneck in scientific workflows. We describe pR, a runtime framework for automatic and transparent parallelization of the popular R language used in statistical computing. Recognizing scripting languages interpreted nature and data analysis codes use pattern, we propose several novel techniques: (1) applying parallelizing compiler technology to runtime, whole-program dependence analysis of scripting languages, (2) incremental code analysis assisted with evaluation results, and (3) runtime parallelization of file accesses. Our framework does not require any modification to either the source code or the underlying R implementation. Experimental results demonstrate that pR can exploit both task and data parallelism transparently and overall has better performance as well as scalability compared to an existing parallel R package that requires code modification.

Yoginath, Srikanth B [ORNL

2011-01-01T23:59:59.000Z

369

Molecular dynamics beyonds the limits: massive scaling on 72 racks of a BlueGene/P and supercooled glass transition of a 1 billion particles system  

E-Print Network (OSTI)

We report scaling results on the world's largest supercomputer of our recently developed Billions-Body Molecular Dynamics (BBMD) package, which was especially designed for massively parallel simulations of the atomic dynamics in structural glasses and amorphous materials. The code was able to scale up to 72 racks of an IBM BlueGene/P, with a measured 89% efficiency for a system with 100 billion particles. The code speed, with less than 0.14 seconds per iteration in the case of 1 billion particles, paves the way to the study of billion-body structural glasses with a resolution increase of two orders of magnitude with respect to the largest simulation ever reported. We demonstrate the effectiveness of our code by studying the liquid-glass transition of an exceptionally large system made by a binary mixture of 1 billion particles.

Allsopp, N; Fratalocchi, A

2011-01-01T23:59:59.000Z

370

Protecting Recovery Act Cleanup Site During Massive Wildfire  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

July 13, 2011 July 13, 2011 Protecting Recovery Act Cleanup Site During Massive Wildfire LOS ALAMOS, N.M. - Effective safety procedures in place at Los Alamos National Laboratory would have provided protections in the event that the raging Las Conchas fire had spread to the site of an American Recovery and Reinvestment Act project. "Our procedures not only placed the waste excavation site, Materials Disposal Area B (MDA-B), into a safe posture so it was well protected during the fire, but also allowed us to resume work quickly," said Project Director Al Chaloupka. The largest wildfire in New Mexico history forced the Lab to close for more than a week. While firefighters battled the fire, Recovery Act project officials were making plans to re-start the Recovery Act excavation of MDA-B when it was safe to return to

371

Baby Brutes: Simulations Help Solve the Mysteries of Massive Young  

NLE Websites -- All DOE Office Websites (Extended Search)

Baby Brutes Baby Brutes Baby Brutes Simulations Help Solve the Mysteries of Massive Young Star-Forming Galaxies March 31, 2010 | Tags: Astrophysics Contact: Margie Wylie, mwylie@lbl.gov, +1 510 486 7421 Primack-fig1a.png Figure 1. In this model galactic plane (seen in cross section), the energy input of stellar superclusters causes gases to shoot out at speeds up to 1000 kilometers per second at temperatures reaching 100 million Kelvin. These appear as plumes or "chimneys," visible in the top three frames (showing density, temperature, and velocity; the bottom frame shows gas column density). Small bubbles of hot gas in the field (visible in the top two frames) are the result of stellar feedback from runaway stars. Astronomers have in recent years been surprised to find hulking brutes

372

Theory of Winds from Hot, Luminous Massive Stars  

E-Print Network (OSTI)

The high luminosities of massive stars drive strong stellar winds, through line scattering of the star's continuum radiation. This paper reviews the dynamics of such line driving, building first upon the standard CAK model for steady winds, and deriving the associated analytic scalings for the mass loss rate and wind velocity law. It next summarizes the origin and nature of the strong Line Deshadowing Instability (LDI) intrinsic to such line-driving, including also the role of a diffuse-line-drag effect that stabilizes the wind base, and then describes how both instability and drag are incorporated in the Smooth Source Function (SSF) method for time-dependent simulations of the nonlinear evolution of the resulting wind structure. The review concludes with a discussion of the effect of the resulting extensive structure in temperature, density and velocity for interpreting observational diagnostics. In addition to the usual clumping effect on density-squared diagnostics, the spatial porosity of optically thick ...

Owocki, Stanley

2014-01-01T23:59:59.000Z

373

Phenomenological QCD equation of state for massive neutron stars  

E-Print Network (OSTI)

We construct an equation of state for massive neutron stars based on quantum chromodynamics phenomenology. Our primary purpose is to delineate the relevant ingredients of equations of state that simultaneously have the required stiffness and satisfy constraints from thermodynamics and causality. These ingredients are: (i) a repulsive density-density interaction, universal for all flavors; (ii) the color-magnetic interaction active from low to high densities; (iii) confining effects, which become increasingly important as the baryon density decreases; (iv) non-perturbative gluons, which are not very sensitive to changes of the quark density. We use the following "3-window" description: At baryon densities below about twice normal nuclear density, 2n_0, we use the Akmal-Pandharipande-Ravenhall (APR) equation of state, and at high densities, > (4-7)n_0, we use the three-flavor Nambu-Jona-Lasinio (NJL) model supplemented by vector and diquark interactions. In the transition density region, we smoothly interpolate...

Kojo, Toru; Song, Yifan; Baym, Gordon

2014-01-01T23:59:59.000Z

374

THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES  

SciTech Connect

We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P {<=} 1 day) binaries. Our sample includes four objects with remarkable log g {approx_equal} 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10 Gyr. Four have {approx}>0.9 M{sub Sun} companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the ELM Survey to 54; 31 of these binaries will merge within a Hubble time.

Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden St, Cambridge, MA 02138 (United States); Kilic, Mukremin; Gianninas, A. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019 (United States); Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es [Instituto de Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain)

2013-05-20T23:59:59.000Z

375

LIMB-DARKENED RADIATION-DRIVEN WINDS FROM MASSIVE STARS  

SciTech Connect

We calculated the influence of the limb-darkened finite-disk correction factor in the theory of radiation-driven winds from massive stars. We solved the one-dimensional m-CAK hydrodynamical equation of rotating radiation-driven winds for all three known solutions, i.e., fast, {Omega}-slow, and {delta}-slow. We found that for the fast solution, the mass-loss rate is increased by a factor of {approx}10%, while the terminal velocity is reduced about 10%, when compared with the solution using a finite-disk correction factor from a uniformly bright star. For the other two slow solutions, the changes are almost negligible. Although we found that the limb darkening has no effects on the wind-momentum-luminosity relationship, it would affect the calculation of synthetic line profiles and the derivation of accurate wind parameters.

Cure, M. [Departamento de Fisica y Astronomia, Facultad de Ciencias, Universidad de Valparaiso, Av. Gran Bretana 1111, Casilla 5030, Valparaiso (Chile); Cidale, L. [Departamento de Espectroscopia, Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata (UNLP), Paseo del Bosque S/N, 1900 La Plata (Argentina); Rial, D. F., E-mail: michel.cure@uv.cl, E-mail: lydia@fcaglp.unlp.edu.ar, E-mail: drial@dm.uba.ar [Departamento de Matematicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina)

2012-10-01T23:59:59.000Z

376

Consistent metric combinations in cosmology of massive bigravity  

E-Print Network (OSTI)

Massive bigravity models are interesting alternatives to standard cosmology. In most cases however these models have been studied for a simplified scenario in which both metrics take homogeneous and isotropic forms (Friedmann-Lema\\^{i}tre-Robertson-Walker; FLRW) with the same spatial curvatures. The interest to consider more general geometries arises in particular in view of the difficulty so far encountered in building stable cosmological solutions with homogeneous and isotropic metrics. Here we consider a number of cases in which the two metrics take more general forms, namely FLRW with different spatial curvatures, Lema\\^{i}tre, Lema\\^{i}tre-Tolman-Bondi (LTB), and Bianchi I, as well as cases where only one metric is linearly perturbed. We discuss possible consistent combinations and find that only some special cases of FLRW-Lema\\^{i}tre, LTB-LTB and FLRW-Bianchi I combinations give consistent, non-trivial solutions.

Henrik Nersisyan; Yashar Akrami; Luca Amendola

2015-02-13T23:59:59.000Z

377

EFTCAMB/EFTCosmoMC: massive neutrinos in dark cosmologies  

E-Print Network (OSTI)

We revisit the degeneracy between massive neutrinos and generalized theories of gravity in the framework of effective field theory of cosmic acceleration. In particular we consider f(R) theories and a class of non-minimally coupled models parametrized via a coupling to gravity which is linear in the scale factor. In the former case, we find a slightly lower degeneracy with respect to what found so far in the literature, due to the fact that we implement exact designer f(R) models and evolve the full linear dynamics of perturbations. As a consequence, our bounds are slightly tighter on the f(R) parameter but looser on the summed neutrino mass. We also set a new upper bound on the Compton wavelength parameter ${\\rm Log}_{10}B_0dark energy survey. We do...

Hu, Bin; Silvestri, Alessandra; Frusciante, Noemi

2014-01-01T23:59:59.000Z

378

DWARF GALAXIES WITH OPTICAL SIGNATURES OF ACTIVE MASSIVE BLACK HOLES  

SciTech Connect

We present a sample of 151 dwarf galaxies (10{sup 8.5} ?< M{sub *} ?< 10{sup 9.5} M{sub ?}) that exhibit optical spectroscopic signatures of accreting massive black holes (BHs), increasing the number of known active galaxies in this stellar-mass range by more than an order of magnitude. Utilizing data from the Sloan Digital Sky Survey Data Release 8 and stellar masses from the NASA-Sloan Atlas, we have systematically searched for active BHs in ?25,000 emission-line galaxies with stellar masses comparable to the Magellanic Clouds and redshifts z < 0.055. Using the narrow-line [O III]/H? versus [N II]/H? diagnostic diagram, we find photoionization signatures of BH accretion in 136 galaxies, a small fraction of which also exhibit broad H? emission. For these broad-line active galactic nucleus (AGN) candidates, we estimate BH masses using standard virial techniques and find a range of 10{sup 5} ?< M{sub BH} ?< 10{sup 6} M{sub ?} and a median of M{sub BH} ? 2 × 10{sup 5} M{sub ?}. We also detect broad H? in 15 galaxies that have narrow-line ratios consistent with star-forming galaxies. Follow-up observations are required to determine if these are true type 1 AGN or if the broad H? is from stellar processes. The median absolute magnitude of the host galaxies in our active sample is M{sub g} = –18.1 mag, which is ?1-2 mag fainter than previous samples of AGN hosts with low-mass BHs. This work constrains the smallest galaxies that can form a massive BH, with implications for BH feedback in low-mass galaxies and the origin of the first supermassive BH seeds.

Reines, Amy E. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Geha, Marla, E-mail: areines@nrao.edu [Department of Astronomy, Yale University, New Haven, CT 06520 (United States)

2013-10-01T23:59:59.000Z

379

A Scalable Message Passing Interface Implementation of an Ad-Hoc Parallel I/o system  

Science Journals Connector (OSTI)

In this paper we present the novel design, implementation, and evaluation of an ad-hoc parallel I/O system (AHPIOS). AHPIOS is the first scalable parallel I/O system completely implemented in the Message Passing Interface (MPI). The MPI implementation ... Keywords: distributed file systems, parallel I/O, parallel systems, parallelism and concurrency

Florin Isaila; Francisco Javier Garcia Blas; Jesús Carretero; Wei-Keng Liao; Alok Choudhary

2010-05-01T23:59:59.000Z

380

Petascale Parallelization of the Gyrokinetic Toroidal Code  

SciTech Connect

The Gyrokinetic Toroidal Code (GTC) is a global, three-dimensional particle-in-cell application developed to study microturbulence in tokamak fusion devices. The global capability of GTC is unique, allowing researchers to systematically analyze important dynamics such as turbulence spreading. In this work we examine a new radial domain decomposition approach to allow scalability onto the latest generation of petascale systems. Extensive performance evaluation is conducted on three high performance computing systems: the IBM BG/P, the Cray XT4, and an Intel Xeon Cluster. Overall results show that the radial decomposition approach dramatically increases scalability, while reducing the memory footprint - allowing for fusion device simulations at an unprecedented scale. After a decade where high-end computing (HEC) was dominated by the rapid pace of improvements to processor frequencies, the performance of next-generation supercomputers is increasingly differentiated by varying interconnect designs and levels of integration. Understanding the tradeoffs of these system designs is a key step towards making effective petascale computing a reality. In this work, we examine a new parallelization scheme for the Gyrokinetic Toroidal Code (GTC) [?] micro-turbulence fusion application. Extensive scalability results and analysis are presented on three HEC systems: the IBM BlueGene/P (BG/P) at Argonne National Laboratory, the Cray XT4 at Lawrence Berkeley National Laboratory, and an Intel Xeon cluster at Lawrence Livermore National Laboratory. Overall results indicate that the new radial decomposition approach successfully attains unprecedented scalability to 131,072 BG/P cores by overcoming the memory limitations of the previous approach. The new version is well suited to utilize emerging petascale resources to access new regimes of physical phenomena.

Ethier, Stephane; Adams, Mark; Carter, Jonathan; Oliker, Leonid

2010-05-01T23:59:59.000Z

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


381

Automatic Thread Distribution For Nested Parallelism In OpenMP OpenMP is becoming the standard programming model for sharedmemory parallel architectures. One of its most inter-  

E-Print Network (OSTI)

Automatic Thread Distribution For Nested Parallelism In OpenMP Abstract OpenMP is becoming in the language is the support for nested parallelism. Previous research and parallelization experiences have shown the benefits of using nested parallelism as an alternative to combining several programming models

Corbalan, Julita

382

AutoAuto--tuned nested parallelism: a way totuned nested parallelism: a way to reduce the execution time of scientificreduce the execution time of scientific  

E-Print Network (OSTI)

AutoAuto--tuned nested parallelism: a way totuned nested parallelism: a way to reduce the execution problems AutoAuto--tuned nested parallelism: a way to reduce the execution time of scientific software in NUMA systemstuned nested parallelism: a way to reduce the execution time of scientific software in NUMA

Giménez, Domingo

383

Motion of Spin 1/2 Massive Particle in a Curved Spacetime  

E-Print Network (OSTI)

Quasi-classical picture of motion of spin 1/2 massive particle in a curved spacetime is built on base of simple Lagrangian model. The one is constructed due to analogy with Lagrangian of massive vector particle. Equations of motion and spin propagation coincide with Papapetrou equations describing dynamic of classical spinning particle in a curved spacetime.

A. T. Muminov

2007-09-28T23:59:59.000Z

384

Evolution of massive Be and Oe stars at low metallicity towards the Long Gamma Ray bursts  

E-Print Network (OSTI)

Evolution of massive Be and Oe stars at low metallicity towards the Long Gamma Ray bursts C and massive stars, and the theoretical predictions of the characteristics must have the long gamma-ray burst of that document deals with the long soft gamma ray bursts (here type 2 bursts) and their possible relationship

385

ComSIS Vol. 1, No. 1, February 2004 75 Network Models of Massive Datasets  

E-Print Network (OSTI)

ComSIS Vol. 1, No. 1, February 2004 75 Network Models of Massive Datasets Vladimir Boginski 1 overview of the methodology of modeling massive datasets arising in various applications as networks. This approach is often useful for extracting non-trivial information from the datasets by applying standard

Butenko, Sergiy

386

Dynamics of a Massive Piston in an Ideal Gas N. Chernov1,4  

E-Print Network (OSTI)

Dynamics of a Massive Piston in an Ideal Gas N. Chernov1,4 , J. L. Lebowitz2,4 , and Ya. Sinai3 January 1, 2003 Abstract We study a dynamical system consisting of a massive piston in a cubical con- tainer of large size L filled with an ideal gas. The piston has mass M L2 and undergoes elastic

387

A Parallel Tree code for large Nbody simulation: dynamic load balance and data distribution on CRAY T3D system  

E-Print Network (OSTI)

N-body algorithms for long-range unscreened interactions like gravity belong to a class of highly irregular problems whose optimal solution is a challenging task for present-day massively parallel computers. In this paper we describe a strategy for optimal memory and work distribution which we have applied to our parallel implementation of the Barnes & Hut (1986) recursive tree scheme on a Cray T3D using the CRAFT programming environment. We have performed a series of tests to find an " optimal data distribution " in the T3D memory, and to identify a strategy for the " Dynamic Load Balance " in order to obtain good performances when running large simulations (more than 10 million particles). The results of tests show that the step duration depends on two main factors: the data locality and the T3D network contention. Increasing data locality we are able to minimize the step duration if the closest bodies (direct interaction) tend to be located in the same PE local memory (contiguous block subdivison, high granularity), whereas the tree properties have a fine grain distribution. In a very large simulation, due to network contention, an unbalanced load arises. To remedy this we have devised an automatic work redistribution mechanism which provided a good Dynamic Load Balance at the price of an insignificant overhead.

U. Becciani; R. Ansaloni; V. Antonuccio-Delogu; G. Erbacci; M. Gambera; A. Pagliaro; -

1997-09-02T23:59:59.000Z

388

The IBM external user interface for scalable parallel systems  

Science Journals Connector (OSTI)

The IBM External User Interface (EUI) for scalable parallel systems is a parallel programming library designed for the IBM line of scalable parallel computers. The first computer in this line, the IBM 9076 SP1, was announced in February 1993. In essence, the EUI is a library of coordination and communication routines that can be invoked from within FORTRAN or C application programs. The EUI consists of four main components: task management routines, message passing routines, task group routines, and collective communication routines. This paper examines several aspects of the design and development of the EUI.

Vasanth Bala; Jehoshua Bruck; Raymond Bryant; Robert Cypher; Peter de Jong; Pablo Elustondon; D Frye; Alex Ho; Ching-Tien Ho; Gail Irwin; Shlomo Kipnis; Richard Lawrence; Marc Snir

1994-01-01T23:59:59.000Z

389

Parallel Multiphysics Simulations of Charged Particles in Microfluidic Flows  

E-Print Network (OSTI)

The article describes parallel multiphysics simulations of charged particles in microfluidic flows with the waLBerla framework. To this end, three physical effects are coupled: rigid body dynamics, fluid flow modelled by a lattice Boltzmann algorithm, and electric potentials represented by a finite volume discretisation. For solving the finite volume discretisation for the electrostatic forces, a cell-centered multigrid algorithm is developed that conforms to the lattice Boltzmann meshes and the parallel communication structure of waLBerla. The new functionality is validated with suitable benchmark scenarios. Additionally, the parallel scaling and the numerical efficiency of the algorithms are analysed on an advanced supercomputer.

Bartuschat, Dominik

2014-01-01T23:59:59.000Z

390

TECA: A Parallel Toolkit for Extreme Climate Analysis  

SciTech Connect

We present TECA, a parallel toolkit for detecting extreme events in large climate datasets. Modern climate datasets expose parallelism across a number of dimensions: spatial locations, timesteps and ensemble members. We design TECA to exploit these modes of parallelism and demonstrate a prototype implementation for detecting and tracking three classes of extreme events: tropical cyclones, extra-tropical cyclones and atmospheric rivers. We process a modern TB-sized CAM5 simulation dataset with TECA, and demonstrate good runtime performance for the three case studies.

Prabhat, Mr; Ruebel, Oliver; Byna, Surendra; Wu, Kesheng; Li, Fuyu; Wehner, Michael; Bethel, E. Wes

2012-03-12T23:59:59.000Z

391

Scheduling of a parallel workload: Implementation and use of the argonne easy scheduler at PDC  

Science Journals Connector (OSTI)

Scheduling of a workload of parallel jobs on a large parallel computer puts specific demands on a scheduling system. Especially if the objective is to give a good service for the largest parallel jobs. In this pa...

Lars Malinowsky; Per Öster

1998-01-01T23:59:59.000Z

392

Parallel Hough Transform for image processing on a Mesh of Trees architecture  

E-Print Network (OSTI)

on Mesh of Trees parallel computer and also a low memory usage. The developed algorithms were simulated on a cube parallel computer. The results were analyzed and compared to those of other parallel computer models....

Cao, Yang

2012-06-07T23:59:59.000Z

393

Endpoint-based parallel data processing with non-blocking collective instructions in a parallel active messaging interface of a parallel computer  

DOE Patents (OSTI)

Endpoint-based parallel data processing with non-blocking collective instructions in a PAMI of a parallel computer is disclosed. The PAMI is composed of data communications endpoints, each including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task. The compute nodes are coupled for data communications through the PAMI. The parallel application establishes a data communications geometry specifying a set of endpoints that are used in collective operations of the PAMI by associating with the geometry a list of collective algorithms valid for use with the endpoints of the geometry; registering in each endpoint in the geometry a dispatch callback function for a collective operation; and executing without blocking, through a single one of the endpoints in the geometry, an instruction for the collective operation.

Archer, Charles J; Blocksome, Michael A; Cernohous, Bob R; Ratterman, Joseph D; Smith, Brian E

2014-11-11T23:59:59.000Z

394

Global Optimization and Parallelization of Integrity Constraint Checks  

E-Print Network (OSTI)

. The primary objective of global opti­ mization is to produce a global execution plan for a group ngine ( ) ice i c e parallel generation of evaluation plans Figure 1: Basic concept of integrity

Neumaier, Arnold

395

Multibody Analysis of Controlled Aeroelastic Systems on Parallel Computers  

Science Journals Connector (OSTI)

The paper describes the application of parallel techniques to amultibody multidisciplinary formulation. The problem is stated interms of a system of nonlinear Differential-Algebraic Equations(DAE). The paralle...

Giuseppe Quaranta; Pierangelo Masarati; Paolo Mantegazza

2002-08-01T23:59:59.000Z

396

Design and implementation of parallel simulation ranking and selection procedures.  

E-Print Network (OSTI)

??Conventional simulation ranking-and-selection(R&S) procedures are designed and implemented for serial computing environment. However, today's growth of computing power relies more on parallelism rather than faster… (more)

Wu, Yang

2013-01-01T23:59:59.000Z

397

Control system design for a parallel hybrid electric vehicle  

E-Print Network (OSTI)

This thesis addresses the design of control systems for a parallel hybrid electric drive train which is an alternative to conventional passenger vehicles. The principle components of the drive train are a small internal combustion engine...

Buntin, David Leighton

1994-01-01T23:59:59.000Z

398

Optimized control studies of a parallel hybrid electric vehicle  

E-Print Network (OSTI)

This thesis addresses the development of a control scheme to maximize automobile fuel economy and battery state-of-charge (SOC) while meeting exhaust emission standards for parallel hybrid electric vehicles, which are an alternative to conventional...

Bougler, Benedicte Bernadette

1995-01-01T23:59:59.000Z

399

Implementation and testing of a parallel layer peeling algorithm  

E-Print Network (OSTI)

implementation was considered because of the anticipated speedup in the solution of the problem under consideration. The algorithm was implemented on an NCUBE 2 machine, with a total of sixty-four processors. Two variations of the parallel algorithm were...

Gandapur, Tasneem Kausar

2012-06-07T23:59:59.000Z

400

BOUNDED PARALLELISM IN COMPUTER ALGEBRA Stephen Michael Watt  

E-Print Network (OSTI)

BOUNDED PARALLELISM IN COMPUTER ALGEBRA by Stephen Michael Watt A thesis presented in Computer Science Waterloo, Ontario, 1985 c S.M. Watt 1985 #12;Permission has been granted to the National

Watt, Stephen M.

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


401

Applying Load Balancing in Data Parallel Applications Using DASUD  

Science Journals Connector (OSTI)

DASUD (Diffusion Algorithm Searching Unbalanced Domains) algorithm has been implemented in an SPMD parallel-image thinning application to balance the workload in the processors as computation proceeds and was ...

A. Cortés; M. Planas; J. L. Millán…

2003-01-01T23:59:59.000Z

402

Simulating parallel programs on application and system level  

Science Journals Connector (OSTI)

Understanding the measured performance of parallel applications in real systems is difficult—with the aim to utilize the resources available, optimizations deployed in hardware and software layers build up to ...

Julian M. Kunkel

2013-05-01T23:59:59.000Z

403

A parallel hypothesis method of autonomous underwater vehicle navigation  

E-Print Network (OSTI)

This research presents a parallel hypothesis method for autonomous underwater vehicle navigation that enables a vehicle to expand the operating envelope of existing long baseline acoustic navigation systems by incorporating ...

LaPointe, Cara Elizabeth Grupe

2009-01-01T23:59:59.000Z

404

Design and Evaluation of the Hamal Parallel Computer  

E-Print Network (OSTI)

Parallel shared-memory machines with hundreds or thousands of processor-memory nodes have been built; in the future we will see machines with millions or even billions of nodes. Associated with such large systems is a new ...

Grossman, J.P.

2002-12-05T23:59:59.000Z

405

Object-oriented abstractions for communication in parallel programs  

E-Print Network (OSTI)

This thesis details ARMI, a parallel communication library that provides an advanced implementation of the remote method invocation protocol (RMI), which is well suited to object-oriented programs. ARMI is a framework for expressing fine...

Saunders, Steven Mack

2012-06-07T23:59:59.000Z

406

Parallel local search for Steiner trees in graphs  

Science Journals Connector (OSTI)

This paper discusses sequential and parallel local search for the Steiner tree problem ingraphs. We introduce novel neighborhoods whose computational time and space complexityis smaller than those known in the...

M.G.A. Verhoeven; M.E.M. Severens

1999-01-01T23:59:59.000Z

407

Circuit and bond polytopes on series-parallel graphs$  

E-Print Network (OSTI)

Jul 10, 2014 ... In the literature, a circuit is sometimes called simple cycle. ... of the circuits of series-parallel graphs, combined with a theorem of Balas [2, 3].

2014-07-10T23:59:59.000Z

408

Reducing Concurrency Bottlenecks in Parallel I/O Workloads  

SciTech Connect

To enable high performance parallel checkpointing we introduced the Parallel Log Structured File System (PLFS). PLFS is middleware interposed on the file system stack to transform concurrent writing of one application file into many non-concurrently written component files. The promising effectiveness of PLFS makes it important to examine its performance for workloads other than checkpoint capture, notably the different ways that state snapshots may be later read, to make the case for using PLFS in the Exascale I/O stack. Reading a PLFS file involved reading each of its component files. In this paper we identify performance limitations on broader workloads in an early version of PLFS, specifically the need to build and distribute an index for the overall file, and the pressure on the underlying parallel file system's metadata server, and show how PLFS's decomposed components architecture can be exploited to alleviate bottlenecks in the underlying parallel file system.

Manzanares, Adam C. [Los Alamos National Laboratory; Bent, John M. [Los Alamos National Laboratory; Wingate, Meghan [Los Alamos National Laboratory

2011-01-01T23:59:59.000Z

409

Thread Scheduling Mechanisms for Multiple-Context Parallel Processors  

E-Print Network (OSTI)

Scheduling tasks to efficiently use the available processor resources is crucial to minimizing the runtime of applications on shared-memory parallel processors. One factor that contributes to poor processor utilization ...

Fiske, James A. Stuart

1995-06-01T23:59:59.000Z

410

Automatic Parallelization of Object Oriented Models Executed with Inline Solvers  

Science Journals Connector (OSTI)

In this work we report preliminary results of automatically generating parallel code from equation-based models together at two levels: Performing inline expansion of a Runge-Kutta solver combined with fine-gr...

Håkan Lundvall; Peter Fritzson

2007-01-01T23:59:59.000Z

411

Distinguishable patterns of competition, collusion, and parallel action  

E-Print Network (OSTI)

Alternative market structures are distinguishable by the degree of parallel action exhibited by producers. We show that the correlation between output levels varies systematically with the degree of interdependence among ...

Smith, James L.

2003-01-01T23:59:59.000Z

412

Some applications of pipelining techniques in parallel scientific computing  

E-Print Network (OSTI)

In this thesis, we study the applicability of pipelining techniques to the development of parallel algorithms for scientific computation. General principles for pipelining techniques are discussed and two applications, Gram-Schmidt orthogonalization...

Deng, Yuanhua

2012-06-07T23:59:59.000Z

413

3D finite-difference frequency-domain modeling of visco-acoustic wave propagation using a massively parallel direct solver: A feasibility study  

E-Print Network (OSTI)

strategy is implemented to mini- mize numerical dispersion. The stencil incorporates 27 grid points staggered-grid method. Differential operators are discretized with second-order accurate staggered-grid sten and spans two grid intervals. Dispersion analysis shows that four grid points per wavelength provide

Vallée, Martin

414

Electrostatically focused addressable field emission array chips (AFEA's) for high-speed massively parallel maskless digital E-beam direct write lithography and scanning electron microscopy  

DOE Patents (OSTI)

Systems and methods are described for addressable field emission array (AFEA) chips. A method of operating an addressable field-emission array, includes: generating a plurality of electron beams from a pluralitly of emitters that compose the addressable field-emission array; and focusing at least one of the plurality of electron beams with an on-chip electrostatic focusing stack. The systems and methods provide advantages including the avoidance of space-charge blow-up.

Thomas, Clarence E. (Knoxville, TN); Baylor, Larry R. (Farragut, TN); Voelkl, Edgar (Oak Ridge, TN); Simpson, Michael L. (Knoxville, TN); Paulus, Michael J. (Knoxville, TN); Lowndes, Douglas H. (Knoxville, TN); Whealton, John H. (Oak Ridge, TN); Whitson, John C. (Clinton, TN); Wilgen, John B. (Oak Ridge, TN)

2002-12-24T23:59:59.000Z

415

DARK MATTER HALO PROFILES OF MASSIVE CLUSTERS: THEORY VERSUS OBSERVATIONS  

SciTech Connect

Dark-matter-dominated cluster-scale halos act as an important cosmological probe and provide a key testing ground for structure formation theory. Focusing on their mass profiles, we have carried out (gravity-only) simulations of the concordance {Lambda}CDM cosmology, covering a mass range of 2 Multiplication-Sign 10{sup 12} to 2 Multiplication-Sign 10{sup 15} h {sup -1} M{sub Sun} and a redshift range of z = 0-2, while satisfying the associated requirements of resolution and statistical control. When fitting to the Navarro-Frenk-White profile, our concentration-mass (c-M) relation differs in normalization and shape in comparison to previous studies that have limited statistics in the upper end of the mass range. We show that the flattening of the c-M relation with redshift is naturally expressed if c is viewed as a function of the peak height parameter, {nu}. Unlike the c-M relation, the slope of the c-{nu} relation is effectively constant over the redshift range z = 0-2, while the amplitude varies by {approx}30% for massive clusters. This relation is, however, not universal: using a simulation suite covering the allowed wCDM parameter space, we show that the c-{nu} relation varies by about {+-}20% as cosmological parameters are varied. At fixed mass, the c(M) distribution is well fit by a Gaussian with {sigma}{sub c}/(c) {approx_equal} 1/3, independent of the radius at which the concentration is defined, the halo dynamical state, and the underlying cosmology. We compare the {Lambda}CDM predictions with observations of halo concentrations from strong lensing, weak lensing, galaxy kinematics, and X-ray data, finding good agreement for massive clusters (M{sub vir} > 4 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun }), but with some disagreements at lower masses. Because of uncertainty in observational systematics and modeling of baryonic physics, the significance of these discrepancies remains unclear.

Bhattacharya, Suman; Habib, Salman; Heitmann, Katrin [High Energy Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)] [High Energy Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Vikhlinin, Alexey [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-03-20T23:59:59.000Z

416

final report for Center for Programming Models for Scalable Parallel Computing  

SciTech Connect

This is the final report of the work on parallel programming patterns that was part of the Center for Programming Models for Scalable Parallel Computing

Johnson, Ralph E

2013-04-10T23:59:59.000Z

417

Manual 3D Lattice-Boltzmann Parallel code Author: Mike Sukop, Danny Thorne and Haibo Huang  

E-Print Network (OSTI)

Manual ­ 3D Lattice-Boltzmann Parallel code Author: Mike Sukop, Danny Thorne and Haibo Huang Manual ­ 3D Lattice-Boltzmann Parallel code

Sukop, Mike

418

E-Print Network 3.0 - accelerated scalable parallel Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

and excellent suitability for parallel... to control the commodity graphics accelerators and to perform oper- ations associated with a parallel... A Scalable and...

419

E-Print Network 3.0 - advanced parallel processing Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

parallel processing Search Powered by Explorit Topic List Advanced Search Sample search results for: advanced parallel processing Page: << < 1 2 3 4 5 > >> 1 Introduction to the...

420

Shock-heating of stellar envelopes: a possible common mechanism at the origin of explosions and eruptions in massive stars  

Science Journals Connector (OSTI)

......generally, the low binding energy of massive-star envelopes...example. The origin of the energy deposition that we artificially...explosion or to a fizzle. Alternative sources in massive stars...objects with low binding energy, they may still be of...massive stars such as Car (not directly addressed......

Luc Dessart; Eli Livne; Roni Waldman

2010-07-11T23:59:59.000Z

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


421

The role of low-mass star clusters in massive star formation in Orion  

E-Print Network (OSTI)

To distinguish between the different theories proposed to explain massive star formation, it is crucial to establish the distribution, the extinction, and the density of low-mass stars in massive star-forming regions. We analyzed deep X-ray observations of the Orion massive star-forming region using the Chandra Orion Ultradeep Project (COUP) catalog. We found that pre-main sequence (PMS) low-mass stars cluster toward the three massive star-forming regions: the Trapezium Cluster (TC), the Orion Hot Core (OHC), and OMC1-S. We derived low-mass stellar densities of 10^{5} stars pc^{-3} in the TC and OMC1-S, and of 10^{6} stars pc^{-3} in the OHC. The close association between the low-mass star clusters with massive star cradles supports the role of these clusters in the formation of massive stars. The X-ray observations show for the first time in the TC that low-mass stars with intermediate extinction are clustered toward the position of the most massive star, which is surrounded by a ring of non-extincted low-ma...

Rivilla, V M; Jimenez-Serra, I; Rodriguez-Franco, A

2013-01-01T23:59:59.000Z

422

Must linear algebra be block cyclic? : and other explorations into the expressivity of data parallel and task parallel languages  

E-Print Network (OSTI)

Prevailing Parallel Linear Algebra software block cyclically distributes data across its processors for good load balancing and communication between its nodes. The block cyclic distribution schema characterized by cyclic ...

Sundaresh, Harish Peruvamba

2007-01-01T23:59:59.000Z

423

Massive-muon-pair production at high energy  

Science Journals Connector (OSTI)

A detailed analysis of the inclusive massive-?-pair production process in high-energy proton-proton collisions is presented based on the combined assumptions of light-cone (LC) expansions and multi-Regge theory. The scaling limit is LC dominated and the assumed strongly convergent Regge theory leads to dominance by the leading LC singularities. The resulting amplitude is expressed as a sum of two distinct contributions, a "pionization" piece, which dominates at large dimuon mass M, and a "fragmentation" piece, which dominates at smaller M. The result of the combination of these two contributions, each of fast decrease in M, can produce a shoulder in the d ?dM cross section, as seems to be present experimentally. This requires a small, perhaps vanishing, Pomeron-particle-Pomeron coupling at t=0. A phenomenological model, which simply incorporates the derived behaviors of the scattering amplitude, is introduced to fit the data quantitatively. A good fit to the d ?dM data (at fixed energy) fixes the (five) parameters. The model then is compared with the experimental curves for the transverse and longitudinal dimuon cross sections and the total (energy-dependent) cross section. Good agreement is found. A comparison with the parton model is also given.

R. A. Brandt, A. Kaufman, and G. Preparata

1974-07-01T23:59:59.000Z

424

Observational constraints on growth of massive black holes  

E-Print Network (OSTI)

We study the observational constraints on the growth of massive black holes (BHs) in galactic nuclei. We use the velocity dispersions of early-type galaxies obtained by the SDSS and the relation between BH mass and velocity dispersion to estimate the local BH mass density to be 2.5x10^5 Msun/Mpc^3. We also use the QSO luminosity function from the 2dF Redshift Survey to estimate the BH mass density accreted during optically bright QSO phases. The local BH mass density is consistent with the density accreted during optically bright QSO phases if QSOs have an efficiency 0.1. By studying the continuity equation for the BH mass distribution, including the effect of BH mergers, we find relations between the local BH mass function and the QSO luminosity function. If the BH mass is assumed to be conserved during BH mergers, comparison of the predicted relations with the observations suggests that luminous QSOs (L_{bol}>10^{46} erg/s) have a high efficiency (e.g. 0.2), and the growth of high-mass BHs (>10^8 Msun) comes mainly from accretion during optically bright QSO phases, or that luminous QSOs have a super-Eddington luminosity. If luminous QSOs are not accreting with super-Eddington luminosities and the growth of low-mass BHs also occurs mainly during optically bright QSO phases, less luminous QSOs must accrete with a low efficiency 0.1.

Qingjuan Yu; Scott Tremaine

2002-05-16T23:59:59.000Z

425

Vacuum energy density and pressure of a massive scalar field  

E-Print Network (OSTI)

With a view toward application of the Pauli-Villars regularization method to the Casimir energy of boundaries, we calculate the expectation values of the components of the stress tensor of a confined massive field in 1+1 space-time dimensions. Previous papers by Hays and Fulling are bridged and generalized. The Green function for the time-independent Schrodinger equation is constructed from the Green function for the whole line by the method of images; equivalently, the one-dimensional system is solved exactly in terms of closed classical paths and periodic orbits. Terms in the energy density and in the eigenvalue density attributable to the two boundaries individually and those attributable to the confinement of the field to a finite interval are distinguished so that their physical origins are clear. Then the pressure is found similarly from the cylinder kernel, the Green function associated most directly with an exponential frequency cutoff of the Fourier mode expansion. Finally, we discuss how the theory could be rendered finite by the Pauli-Villars method.

Fernando Daniel Mera; S. A. Fulling

2014-12-29T23:59:59.000Z

426

HERSCHEL REVEALS MASSIVE COLD CLUMPS IN NGC 7538  

SciTech Connect

We present the first overview of the Herschel observations of the nearby high-mass star-forming region NGC 7538, taken as part of the Herschel imaging study of OB young stellar objects (HOBYS) Key Programme. These PACS and SPIRE maps cover an approximate area of one square degree at five submillimeter and far-infrared wavebands. We have identified 780 dense sources and classified 224 of those. With the intention of investigating the existence of cold massive starless or class 0-like clumps that would have the potential to form intermediate- to high-mass stars, we further isolate 13 clumps as the most likely candidates for follow-up studies. These 13 clumps have masses in excess of 40 M{sub Sun} and temperatures below 15 K. They range in size from 0.4 pc to 2.5 pc and have densities between 3 Multiplication-Sign 10{sup 3} cm{sup -3} and 4 Multiplication-Sign 10{sup 4} cm{sup -3}. Spectral energy distributions are then used to characterize their energetics and evolutionary state through a luminosity-mass diagram. NGC 7538 has a highly filamentary structure, previously unseen in the dust continuum of existing submillimeter surveys. We report the most complete imaging to date of a large, evacuated ring of material in NGC 7538 which is bordered by many cool sources.

Fallscheer, C.; Di Francesco, J.; Sadavoy, S. [Department of Physics and Astronomy, University of Victoria, P.O. Box 355, STN CSC, Victoria, BC V8W 3P6 (Canada); Reid, M. A. [Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4 (Canada); Martin, P. G.; Nguyen-Luong, Q. [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada); Hill, T.; Hennemann, M.; Motte, F.; Men'shchikov, A.; Andre, Ph.; Konyves, V.; Sauvage, M. [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, IRFU/Service d'Astrophysique, Saclay, F-91191 Gif-sur-Yvette (France); Ward-Thompson, D.; Kirk, J. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston, Lancashire, PR1 2HE (United Kingdom); Griffin, M. [School of Physics and Astronomy, Cardiff University, Queen's Buildings, The Parade, Cardiff CF24 3AA (United Kingdom); Rygl, K. L. J.; Benedettini, M. [INAF, Istituto di Astrofisica e Planetologia Spaziali, Area di Ricerca di Tor Vergata, via Fosso del Cavaliere 100, I-00133 Roma (Italy); Schneider, N. [Universite de Bordeaux, LAB, UMR 5804, F-33270, Floirac (France); Anderson, L. D. [Laboratoire d'Astrophysique de Marseille, CNRS/INSU, Universite de Provence, F-13388 Marseille Cedex 13 (France); and others

2013-08-20T23:59:59.000Z

427

Instabilities in the Envelopes and Winds of Very Massive Stars  

E-Print Network (OSTI)

The high luminosity of Very Massive Stars (VMS) means that radiative forces play an important, dynamical role both in the structure and stability of their stellar envelope, and in driving strong stellar-wind mass loss. Focusing on the interplay of radiative flux and opacity, with emphasis on key distinctions between continuum vs. line opacity, this chapter reviews instabilities in the envelopes and winds of VMS. Specifically, we discuss how: 1) the iron opacity bump can induce an extensive inflation of the stellar envelope; 2) the density dependence of mean opacity leads to strange mode instabilities in the outer envelope; 3) desaturation of line-opacity by acceleration of near-surface layers initiates and sustains a line-driven stellar wind outflow; 4) an associated line-deshadowing instability leads to extensive small-scale structure in the outer regions of such line-driven winds; 5) a star with super-Eddington luminosity can develop extensive atmospheric structure from photon bubble instabilities, or from ...

Owocki, Stanley P

2014-01-01T23:59:59.000Z

428

Vacuum energy density and pressure of a massive scalar field  

E-Print Network (OSTI)

With a view toward application of the Pauli-Villars regularization method to the Casimir energy of boundaries, we calculate the expectation values of the components of the stress tensor of a confined massive field in 1+1 space-time dimensions. Previous papers by Hays and Fulling are bridged and generalized. The Green function for the time-independent Schrodinger equation is constructed from the Green function for the whole line by the method of images; equivalently, the one-dimensional system is solved exactly in terms of closed classical paths and periodic orbits. Terms in the energy density and in the eigenvalue density attributable to the two boundaries individually and those attributable to the confinement of the field to a finite interval are distinguished so that their physical origins are clear. Then the pressure is found similarly from the cylinder kernel, the Green function associated most directly with an exponential frequency cutoff of the Fourier mode expansion. Finally, we discuss how the theory could be rendered finite by the Pauli-Villars method.

Fernando Daniel Mera; S. A. Fulling

2015-02-15T23:59:59.000Z

429

Outflow Feedback Regulated Massive Star Formation in Parsec-Scale Cluster Forming Clumps  

SciTech Connect

We investigate massive star formation in turbulent, magnetized, parsec-scale clumps of molecular clouds including protostellar outflow feedback using three dimensional numerical simulations of effective resolution 2048{sup 3}. The calculations are carried out using a block structured adaptive mesh refinement code that solves the ideal MHD equations including self-gravity and implements accreting sink particles. We find that, in the absence of regulation by magnetic fields and outflow feedback, massive stars form readily in a turbulent, moderately condensed clump of {approx} 1,600 M{sub {circle_dot}} (containing {approx} 10{sup 2} initial Jeans masses), along with a cluster of hundreds of lower mass stars. The massive stars are fed at high rates by (1) transient dense filaments produced by large-scale turbulent compression at early times, and (2) by the clump-wide global collapse resulting from turbulence decay at late times. In both cases, the bulk of the massive star's mass is supplied from outside a 0.1 pc-sized 'core' that surrounds the star. In our simulation, the massive star is clump-fed rather than core-fed. The need for large-scale feeding makes the massive star formation prone to regulation by outflow feedback, which directly opposes the feeding processes. The outflows reduce the mass accretion rates onto the massive stars by breaking up the dense filaments that feed the massive star formation at early times, and by collectively slowing down the global collapse that fuel the massive star formation at late times. The latter is aided by a moderate magnetic field of strength in the observed range (corresponding to a dimensionless clump mass-to-flux ratio {lambda} {approx} a few); the field allows the outflow momenta to be deposited more efficiently inside the clump. We conclude that the massive star formation in our simulated turbulent, magnetized, parsec-scale clump is outflow-regulated and clump-fed (ORCF for short). An important implication is that the formation of low-mass stars in a dense clump can affect the formation of massive stars in the same clump, through their outflow feedback on the clump dynamics. In a companion paper, we discuss the properties of the lower mass cluster members formed along with the massive stars, including their mass distribution and spatial clustering.

Wang, Peng; /KIPAC, Menlo Park /Stanford U., Phys.Dept.; Li, Zhi-Yun; /Virginia U., Astron. Dept.; Abel, Tom; /KIPAC, Menlo Park /Stanford U., Phys.Dept.; Nakamura, Fumitaka; /Niigata U.

2010-02-15T23:59:59.000Z

430

IRAS 23385+6053: a candidate protostellar massive object  

E-Print Network (OSTI)

We present the results of a multi-line and continuum study towards the source IRAS 23385+6053,performed with the IRAM-30m telescope, the Plateau de Bure Interferometer, the Very Large Array Interferometer and the James Clerk Maxwell Telescope. The new results confirm our earlier findings, namely that IRAS 23385+6053 is a good candidate high-mass protostellar object, precursor of an ultracompact H$_{II}$ region. The source is roughly composed of two regions: a molecular core $\\sim0.03\\div0.04$ pc in size, with a temperature of $\\sim40$ K and an H$_{2}$ volume density of the order of 10$^{7}$ cm$^{-3}$, and an extended halo of diameter $\\leq$0.4 pc, with an average kinetic temperature of $\\sim 15$ K and H$_{2}$ volume density of the order of 10$^{5}$ cm$^{-3}$. The core temperature is much smaller than what is typically found in molecular cores of the same diameter surrounding massive ZAMS stars. We deduce that the core luminosity is between 150 and $1.6\\times10^{4}L_{\\odot}$, and we believe that the upper limit is near the ``true'' source luminosity. Moreover, by comparing the H$_{2}$ volume density obtained at different radii from the IRAS source, we find that the halo has a density profile of the type $n_{\\rm H_{2}}\\propto r^{-2.3}$. This suggests that the source is gravitationally unstable. Finally, we demonstrate that the temperature at the core surface is consistent with a core luminosity of $10^3 L_{\\odot}$ and conclude that we might be observing a protostar still accreting material from its parental cloud, whose mass at present is $\\sim 6 M_{\\odot}$.

F. Fontani; R. Cesaroni; L. Testi; C. M. Walmsley; S. Molinari; R. Neri; D. Shepherd; J. Brand; F. Palla; Q. Zhang

2003-10-15T23:59:59.000Z

431

Fallback and Black Hole Production in Massive Stars  

SciTech Connect

The compact remnants of core collapse supernovae--neutron stars and black holes--have properties that reflect both the structure of their stellar progenitors and the physics of the explosion. In particular, the masses of these remnants are sensitive to the density structure of the presupernova star and to the explosion energy. To a considerable extent, the final mass is determined by the ''fallback'', during the explosion, of matter that initially moves outwards, yet ultimately fails to escape. We consider here the simulated explosion of a large number of massive stars (10 to 100 M{sub {circle_dot}}) of Population I (solar metallicity) and III (zero metallicity), and find systematic differences in the remnant mass distributions. As pointed out by Chevalier (1989), supernovae in more compact progenitor stars have stronger reverse shocks and experience more fallback. For Population III stars above about 25 M{sub {circle_dot}} and explosion energies less than 1.5 x 10{sup 51} erg, black holes are a common outcome, with masses that increase monotonically with increasing main sequence mass up to a maximum hole mass of about 35 M{sub {circle_dot}}. If such stars produce primary nitrogen, however, their black holes are systematically smaller. For modern supernovae with nearly solar metallicity, black hole production is much less frequent and the typical masses, which depend sensitively on explosion energy, are smaller. We explore the neutron star initial mass function for both populations and, for reasonable assumptions about the initial mass cut of the explosion, find good agreement with the average of observed masses of neutron stars in binaries. We also find evidence for a bimodal distribution of neutron star masses with a spike around 1.2 M{sub {circle_dot}} (gravitational mass) and a broader distribution peaked around 1.4 M{sub {circle_dot}}.

Zhang, Wei-Qun; /KIPAC, Menlo Park; Woosley, S.E.; /UC, Santa Cruz; Heger, A.; /UC, Santa Cruz /Los Alamos

2007-01-08T23:59:59.000Z

432

Workers Pour 1 Million Gallons of Grout into Massive Tanks | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Workers Pour 1 Million Gallons of Grout into Massive Tanks Workers Pour 1 Million Gallons of Grout into Massive Tanks Workers Pour 1 Million Gallons of Grout into Massive Tanks May 15, 2012 - 12:00pm Addthis Cement trucks transport a specially formulated grout that is pumped into the waste tanks. Cement trucks transport a specially formulated grout that is pumped into the waste tanks. AIKEN, S.C. - Workers have poured more than 1 million gallons of a cement-like grout into two underground radioactive waste tanks, moving the Savannah River Site (SRS) nearer to closing the massive structures. SRS and liquid waste contractor Savannah River Remediation are working to fill the 1.3-million-gallon Tanks 18 and 19 with grout, a project that began April 2. Grouting of the tanks, ancillary piping and equipment is scheduled for completion in late summer.

433

Testing gravity at the Second post-Newtonian level through gravitational deflection of massive particles  

E-Print Network (OSTI)

Expression for second post-Newtonian level gravitational deflection angle of massive particles is obtained in a model independent framework. Several of its important implications including the possibility of testing gravitational theories at that level are discussed.

A. Bhadra; K. Sarkar; K. K. Nandi

2006-10-18T23:59:59.000Z

434

Ecology and evolution simulation and quest design for an educational massive multiplayer online game  

E-Print Network (OSTI)

In this design-based research project, I developed two simulations to be used as student tools in a massively multiplayer online game targeted at STEM education, the Radix Endeavor. I designed both the underlying agent-based ...

Zhang, Mark (Mark A.)

2013-01-01T23:59:59.000Z

435

THE RED MSX SOURCE SURVEY: THE MASSIVE YOUNG STELLAR POPULATION OF OUR GALAXY  

SciTech Connect

We present the Red MSX Source survey, the largest statistically selected catalog of young massive protostars and H II regions to date. We outline the construction of the catalog using mid- and near-infrared color selection. We also discuss the detailed follow up work at other wavelengths, including higher spatial resolution data in the infrared. We show that within the adopted selection bounds we are more than 90% complete for the massive protostellar population, with a positional accuracy of the exciting source of better than 2 arcsec. We briefly summarize some of the results that can be obtained from studying the properties of the objects in the catalog as a whole; we find evidence that the most massive stars form: (1) preferentially nearer the Galactic center than the anti-center; (2) in the most heavily reddened environments, suggestive of high accretion rates; and (3) from the most massive cloud cores.

Lumsden, S. L.; Hoare, M. G.; Oudmaijer, R. D.; Cooper, H. D. B. [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Urquhart, J. S. [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, Bonn (Germany); Davies, B.; Moore, T. J. T. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Mottram, J. C. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)

2013-09-01T23:59:59.000Z

436

Parallel Breadth-First Search on Distributed Memory Systems  

SciTech Connect

Data-intensive, graph-based computations are pervasive in several scientific applications, and are known to to be quite challenging to implement on distributed memory systems. In this work, we explore the design space of parallel algorithms for Breadth-First Search (BFS), a key subroutine in several graph algorithms. We present two highly-tuned par- allel approaches for BFS on large parallel systems: a level-synchronous strategy that relies on a simple vertex-based partitioning of the graph, and a two-dimensional sparse matrix- partitioning-based approach that mitigates parallel commu- nication overhead. For both approaches, we also present hybrid versions with intra-node multithreading. Our novel hybrid two-dimensional algorithm reduces communication times by up to a factor of 3.5, relative to a common vertex based approach. Our experimental study identifies execu- tion regimes in which these approaches will be competitive, and we demonstrate extremely high performance on lead- ing distributed-memory parallel systems. For instance, for a 40,000-core parallel execution on Hopper, an AMD Magny- Cours based system, we achieve a BFS performance rate of 17.8 billion edge visits per second on an undirected graph of 4.3 billion vertices and 68.7 billion edges with skewed degree distribution.

Computational Research Division; Buluc, Aydin; Madduri, Kamesh

2011-04-15T23:59:59.000Z

437

Parallel heat transport in integrable and chaotic magnetic fields  

SciTech Connect

The study of transport in magnetized plasmas is a problem of fundamental interest in controlled fusion, space plasmas, and astrophysics research. Three issues make this problem particularly challenging: (i) The extreme anisotropy between the parallel (i.e., along the magnetic field), {chi}{sub ||} , and the perpendicular, {chi}{sub Up-Tack }, conductivities ({chi}{sub ||} /{chi}{sub Up-Tack} may exceed 10{sup 10} in fusion plasmas); (ii) Nonlocal parallel transport in the limit of small collisionality; and (iii) Magnetic field lines chaos which in general complicates (and may preclude) the construction of magnetic field line coordinates. Motivated by these issues, we present a Lagrangian Green's function method to solve the local and non-local parallel transport equation applicable to integrable and chaotic magnetic fields in arbitrary geometry. The method avoids by construction the numerical pollution issues of grid-based algorithms. The potential of the approach is demonstrated with nontrivial applications to integrable (magnetic island), weakly chaotic (Devil's staircase), and fully chaotic magnetic field configurations. For the latter, numerical solutions of the parallel heat transport equation show that the effective radial transport, with local and non-local parallel closures, is non-diffusive, thus casting doubts on the applicability of quasilinear diffusion descriptions. General conditions for the existence of non-diffusive, multivalued flux-gradient relations in the temperature evolution are derived.

Castillo-Negrete, D. del; Chacon, L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-8071 (United States)

2012-05-15T23:59:59.000Z

438

Experiences and results from designing and developing a 6 DoF underwater parallel robot  

Science Journals Connector (OSTI)

REMO I Robot is a novel application of a parallel structure as an underwater robot of 6 DoF. Compared to other underwater robots, navigation of REMO I Robot is performed by the capability of its parallel structure to modify its geometric structure (thruster ... Keywords: Control of parallel robot, Modelling, Parallel robot, Underwater robots

Roque Saltaren Pazmiño; Cecilia E. Garcia Cena; Cesar Alvarez Arocha; Rafael Aracil Santonja

2011-02-01T23:59:59.000Z

439

Fasteners -- Preloading test for the detection of hydrogen embrittlement -- Parallel bearing surface method  

E-Print Network (OSTI)

Fasteners -- Preloading test for the detection of hydrogen embrittlement -- Parallel bearing surface method

International Organization for Standardization. Geneva

1999-01-01T23:59:59.000Z

440

Parallel MATLAB at VT Gene Cliff (AOE/ICAM -ecliff@vt.edu )  

E-Print Network (OSTI)

Parallel MATLAB at VT Gene Cliff (AOE/ICAM - ecliff@vt.edu ) Justin Krometis (ARC/ICAM - jkrometis Mathematics 1 / 35 #12;MATLAB Parallel Computing Introduction Programming Models Execution Example: Quadrature Conclusion 2 / 35 #12;INTRO: Parallel MATLAB Parallel MATLAB is an extension of MATLAB that takes advantage

Crawford, T. Daniel

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


441

The role of low-mass star clusters in massive star formation. The Orion Case  

E-Print Network (OSTI)

To distinguish between the different theories proposed to explain massive star formation, it is crucial to establish the distribution, the extinction, and the density of low-mass stars in massive star-forming regions. We analyze deep X-ray observations of the Orion massive star-forming region using the Chandra Orion Ultradeep Project (COUP) catalog. We studied the stellar distribution as a function of extinction, with cells of 0.03 pc x 0.03 pc, the typical size of protostellar cores. We derived stellar density maps and calculated cluster stellar densities. We found that low-mass stars cluster toward the three massive star-forming regions: the Trapezium Cluster (TC), the Orion Hot Core (OHC), and OMC1-S. We derived low-mass stellar densities of 10^{5} stars pc^{-3} in the TC and OMC1-S, and of 10^{6} stars pc^{-3} in the OHC. The close association between the low-mass star clusters with massive star cradles supports the role of these clusters in the formation of massive stars. The X-ray observations show for ...

Rivilla, V M; Jimenez-Serra, I; Rodriguez-Franco, A

2013-01-01T23:59:59.000Z

442

Massive-scale RDF Processing Using Compressed Bitmap Indexes  

SciTech Connect

The Resource Description Framework (RDF) is a popular data model for representing linked data sets arising from the web, as well as large scienti#12;c data repositories such as UniProt. RDF data intrinsically represents a labeled and directed multi-graph. SPARQL is a query language for RDF that expresses subgraph pattern-#12;nding queries on this implicit multigraph in a SQL- like syntax. SPARQL queries generate complex intermediate join queries; to compute these joins e#14;ciently, we propose a new strategy based on bitmap indexes. We store the RDF data in column-oriented structures as compressed bitmaps along with two dictionaries. This paper makes three new contributions. (i) We present an e#14;cient parallel strategy for parsing the raw RDF data, building dictionaries of unique entities, and creating compressed bitmap indexes of the data. (ii) We utilize the constructed bitmap indexes to e#14;ciently answer SPARQL queries, simplifying the join evaluations. (iii) To quantify the performance impact of using bitmap indexes, we compare our approach to the state-of-the-art triple-store RDF-3X. We #12;nd that our bitmap index-based approach to answering queries is up to an order of magnitude faster for a variety of SPARQL queries, on gigascale RDF data sets.

Madduri, Kamesh; Wu, Kesheng

2011-05-26T23:59:59.000Z

443

Parallel Scaling Characteristics of Selected NERSC User ProjectCodes  

SciTech Connect

This report documents parallel scaling characteristics of NERSC user project codes between Fiscal Year 2003 and the first half of Fiscal Year 2004 (Oct 2002-March 2004). The codes analyzed cover 60% of all the CPU hours delivered during that time frame on seaborg, a 6080 CPU IBM SP and the largest parallel computer at NERSC. The scale in terms of concurrency and problem size of the workload is analyzed. Drawing on batch queue logs, performance data and feedback from researchers we detail the motivations, benefits, and challenges of implementing highly parallel scientific codes on current NERSC High Performance Computing systems. An evaluation and outlook of the NERSC workload for Allocation Year 2005 is presented.

Skinner, David; Verdier, Francesca; Anand, Harsh; Carter,Jonathan; Durst, Mark; Gerber, Richard

2005-03-05T23:59:59.000Z

444

Parallel Graphics and Interactivity with the Scaleable Graphics Engine  

SciTech Connect

A parallel rendering environment is being developed to utilize the IBM Scaleable Graphics Engine (SGE), a hardware frame buffer for parallel computers. Goals of this software development effort include finding efficient ways of producing and displaying graphics generated on SP nodes and of assisting programmers in adapting or creating scientific simulation applications to use the SGE. Four software development phases are discussed utilize the SGE: tunneling, SMP Rendering, graphics API development using an OpenGL API implementation which utilizes the SGE in the parallel environment, and additions to the SGE-enabled OpenGL API implementation that uses threads. The SGE's ability to accept pixel data from multiple nodes simultaneously makes it a viable tool for use. With the performance observed in the test applications and performance optimizations gained programmers writing applications for IBM SPs and Linux clusters will be able to support high-speed output of graphics and be able to interact with data.

Perrine, Kenneth A.; Jones, Donald R.

2001-11-10T23:59:59.000Z

445

Intelligent energy management agent for a parallel hybrid vehicle  

E-Print Network (OSTI)

INTELLIGENT ENERGY MANAGEMENT AGENT FOR A PARALLEL HYBRID VEHICLE A Dissertation by JONG-SEOB WON Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements for the degree of DOCTOR OF PHILOSOPHY May... 2003 Major Subject: Mechanical Engineering INTELLIGENT ENERGY MANAGEMENT AGENT FOR A PARALLEL HYBRID VEHICLE A Dissertation by JONG-SEOB WON Submitted to Texas A&M University in partial ful llment of the requirements for the degree of DOCTOR...

Won, Jong-Seob

2004-09-30T23:59:59.000Z

446

Small file aggregation in a parallel computing system  

DOE Patents (OSTI)

Techniques are provided for small file aggregation in a parallel computing system. An exemplary method for storing a plurality of files generated by a plurality of processes in a parallel computing system comprises aggregating the plurality of files into a single aggregated file; and generating metadata for the single aggregated file. The metadata comprises an offset and a length of each of the plurality of files in the single aggregated file. The metadata can be used to unpack one or more of the files from the single aggregated file.

Faibish, Sorin; Bent, John M.; Tzelnic, Percy; Grider, Gary; Zhang, Jingwang

2014-09-02T23:59:59.000Z

447

WHAT ARE THE PROGENITORS OF COMPACT, MASSIVE, QUIESCENT GALAXIES AT z = 2.3? THE POPULATION OF MASSIVE GALAXIES AT z > 3 FROM NMBS AND CANDELS  

SciTech Connect

Using public data from the NEWFIRM Medium-Band Survey (NMBS) and the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS), we investigate the population of massive galaxies at z > 3. The main aim of this work is to identify the potential progenitors of z {approx} 2 compact, massive, quiescent galaxies (CMQGs), furthering our understanding of the onset and evolution of massive galaxies. Our work is enabled by high-resolution images from CANDELS data and accurate photometric redshifts, stellar masses, and star formation rates (SFRs) from 37-band NMBS photometry. The total number of massive galaxies at z > 3 is consistent with the number of massive, quiescent galaxies (MQGs) at z {approx} 2, implying that the SFRs for all of these galaxies must be much lower by z {approx} 2. We discover four CMQGs at z > 3, pushing back the time for which such galaxies have been observed. However, the volume density for these galaxies is significantly less than that of galaxies at z < 2 with similar masses, SFRs, and sizes, implying that additional CMQGs must be created in the intervening {approx}1 Gyr between z = 3 and z = 2. We find five star-forming galaxies at z {approx} 3 that are compact (R{sub e} < 1.4 kpc) and have stellar mass M{sub *} > 10{sup 10.6} M{sub Sun }; these galaxies are likely to become members of the massive, quiescent, compact galaxy population at z {approx} 2. We evolve the stellar masses and SFRs of each individual z > 3 galaxy adopting five different star formation histories (SFHs) and studying the resulting population of massive galaxies at z = 2.3. We find that declining or truncated SFHs are necessary to match the observed number density of MQGs at z {approx} 2, whereas a constant delayed-exponential SFH would result in a number density significantly smaller than observed. All of our assumed SFHs imply number densities of CMQGs at z {approx} 2 that are consistent with the observed number density. Better agreement with the observed number density of CMQGs at z {approx} 2 is obtained if merging is included in the analysis and better still if star formation quenching is assumed to shortly follow the merging event, as implied by recent models of the formation of MQGs.

Stefanon, Mauro; Rudnick, Gregory H. [Department of Physics and Astronomy, University of Kansas, Malott Room 1082, 1251 Wescoe Hall Drive, Lawrence, KS 66045 (United States); Marchesini, Danilo [Physics and Astronomy Department, Tufts University, Robinson Hall, Room 257, Medford, MA 02155 (United States); Brammer, Gabriel B. [European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Vitacura, Santiago (Chile); Whitaker, Katherine E., E-mail: stefanonm@missouri.edu [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States)

2013-05-01T23:59:59.000Z

448

Building a Parallel Cloud Storage System using OpenStack’s Swift Object Store and Transformative Parallel I/O  

SciTech Connect

Our project consists of bleeding-edge research into replacing the traditional storage archives with a parallel, cloud-based storage solution. It used OpenStack's Swift Object Store cloud software. It's Benchmarked Swift for write speed and scalability. Our project is unique because Swift is typically used for reads and we are mostly concerned with write speeds. Cloud Storage is a viable archive solution because: (1) Container management for larger parallel archives might ease the migration workload; (2) Many tools that are written for cloud storage could be utilized for local archive; and (3) Current large cloud storage practices in industry could be utilized to manage a scalable archive solution.

Burns, Andrew J. [Los Alamos National Laboratory; Lora, Kaleb D. [Los Alamos National Laboratory; Martinez, Esteban [Los Alamos National Laboratory; Shorter, Martel L. [Los Alamos National Laboratory

2012-07-30T23:59:59.000Z

449

Parallel evolution of chimeric fusion genes Corbin D. Jones*  

E-Print Network (OSTI)

Parallel evolution of chimeric fusion genes Corbin D. Jones* and David J. Begun *Department in Drosophila to guide our analyses. We discovered a fundamental similarity in the temporal, spatial, and types in the evolution of chimeric fusion genes. We suggest that the patterns we observed are both general and predictive

Begun, David

450

Parallel components for PDEs and optimization: some issues and experiences  

Science Journals Connector (OSTI)

High-performance simulations in computational science often involve the combined software contributions of multidisciplinary teams of scientists, engineers, mathematicians, and computer scientists. One goal of component-based software engineering in ... Keywords: component-based software, interface specification, parallel computing, scientific computing

Boyana Norris; Satish Balay; Steven Benson; Lori Freitag; Paul Hovland; Lois McInnes; Barry Smith

2002-12-01T23:59:59.000Z

451

MODELING AND CONTROLLING PARALLEL TASKS IN DROPLET-BASED MICROFLUIDIC  

E-Print Network (OSTI)

Chapter 12 MODELING AND CONTROLLING PARALLEL TASKS IN DROPLET-BASED MICROFLUIDIC SYSTEMS Karl F-independent models and algorithms to automate the operation of droplet-based microfluidic systems. In these systems mapping of a biochemical analysis task onto a droplet-based microfluidic system is investigated. Achieving

452

A Parallel Algorithm for Approximating the Minimum Cycle Cover  

E-Print Network (OSTI)

approximation algorithm for the problem of finding a minimum cycle cover. A cycle cover is a set of cycles cover [1, 7, 8]. The basis for our approximation algorithm is a routine to find a maximal set of edgeA Parallel Algorithm for Approximating the Minimum Cycle Cover Philip Klein \\Lambda Aiken

Yang, Junfeng

453

Optimizing Parallel Sparse Matrix-Vector Multiplication by Corner Partitioning  

E-Print Network (OSTI)

fast to compute. Finally, we propose a graph model for an ordering problem to further optimize our approach. This leads to a graph algorithm based on vertex cover or vertex separator. Key words: parallel nodes to minimize the communication cost. Such "communication" is also important on serial computers

Boman, Erik

454

Parallel Hypergraph Partitioning for Scientific Karen D. Devine  

E-Print Network (OSTI)

that reduces communication cost and achieves maximal performance. Graph partitioning has long served T. Heaphy , Rob H. Bisseling , and Umit V. Catalyurek Abstract Graph partitioning is often used as a useful model for load balancing in parallel computing. Data are represented as vertices in a graph

Boman, Erik

455

A Hierarchical Checkpointing Protocol for Parallel Applications in Cluster Federations  

E-Print Network (OSTI)

A Hierarchical Checkpointing Protocol for Parallel Applications in Cluster Federations S federation. As a cluster federation comprises of a large number of nodes, there is a high probability fits to the characteristics of a cluster federation (large number of nodes, high latency and low

Paris-Sud XI, Université de

456

Evaluating Memory Energy Efficiency in Parallel I/O Workloads  

E-Print Network (OSTI)

Evaluating Memory Energy Efficiency in Parallel I/O Workloads Jianhui Yue,Yifeng Zhu , Zhao Cai the ever- widening gap between disk and processor speeds, memory energy efficiency becomes an increasingly management policies heavily influence the overall memory energy efficiency. In partic- ular, under the same

Zhu, Yifeng

457

Hardware packet pacing using a DMA in a parallel computer  

DOE Patents (OSTI)

Method and system for hardware packet pacing using a direct memory access controller in a parallel computer which, in one aspect, keeps track of a total number of bytes put on the network as a result of a remote get operation, using a hardware token counter.

Chen, Dong; Heidelberger, Phillip; Vranas, Pavlos

2013-08-13T23:59:59.000Z

458

How to write fast and clear parallel programs using algebra  

SciTech Connect

An algebraic method for the design of efficient and easy to port codes for parallel machines is described. The method was applied to speed up and to clarify certain communication functions, n-body codes, a biomolecular analysis, and a chess problem.

Stiller, L. [Los Alamos National Lab., NM (United States)]|[Johns Hopkins Univ., Baltimore, MD (United States)

1992-10-01T23:59:59.000Z

459

How to write fast and clear parallel programs using algebra  

SciTech Connect

An algebraic method for the design of efficient and easy to port codes for parallel machines is described. The method was applied to speed up and to clarify certain communication functions, n-body codes, a biomolecular analysis, and a chess problem.

Stiller, L. (Los Alamos National Lab., NM (United States) Johns Hopkins Univ., Baltimore, MD (United States))

1992-01-01T23:59:59.000Z

460

Efficient data IO for a Parallel Global Cloud Resolving Model  

Science Journals Connector (OSTI)

Execution of a Global Cloud Resolving Model (GCRM) at target resolutions of 2-4 km will generate, at a minimum, 10s of Gigabytes of data per variable per snapshot. Writing this data to disk, without creating a serious bottleneck in the execution of the ... Keywords: Data formatting, Geodesic grid, Global Cloud Resolving Model, Grid Specifications, High performance IO, Parallel IO libraries

Bruce Palmer; Annette Koontz; Karen Schuchardt; Ross Heikes; David Randall

2011-12-01T23:59:59.000Z

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


461

GPU video retargeting with parallelized SeamCrop  

Science Journals Connector (OSTI)

In this paper, we present a fast parallel algorithm for the retargeting of videos. It combines seam carving and cropping and is aimed for real-time adaptation of video streams. The basic idea is to first find an optimal cropping path over the whole sequence ... Keywords: GPU, SeamCrop, cropping, seam carving, video resizing, video retargeting

Johannes Kiess; Daniel Gritzner; Benjamin Guthier; Stephan Kopf; Wolfgang Effelsberg

2014-03-01T23:59:59.000Z

462

High-Resolution, Parallel Visualization of Turbomachinery Flowelds  

E-Print Network (OSTI)

High-Resolution, Parallel Visualization of Turbomachinery Flowelds Michael G. List , Mark G Turbomachinery post- and co-processing and visualization tools are under development. The result has been in the analysis of turbomachinery. It has always been the way of the CFD analyst to expand and resolve simulations

Cincinnati, University of

463

MATLAB*G: A Grid-Based Parallel MATLAB  

E-Print Network (OSTI)

This paper describes the design and implementation of MATLAB*G, a parallel MATLAB on the ALiCE Grid. ALiCE (Adaptive and scaLable internet-based Computing Engine), developed at NUS, is a lightweight grid-computing middleware. ...

Chen, Ying

464

Scalable Load Distribution and Load Balancing for Dynamic Parallel Programs  

E-Print Network (OSTI)

shown that the algorithm scales according to the definition of scalability given following. LoadScalable Load Distribution and Load Balancing for Dynamic Parallel Programs E. Berger and J. C of an integrated load distribution-load balancing algorithm which was targeted to be both efficient and scalable

Berger, Emery

465

Simulating parallel programs on application and system level  

Science Journals Connector (OSTI)

Understanding the measured performance of parallel applications in real systems is difficult--with the aim to utilize the resources available, optimizations deployed in hardware and software layers build up to complex systems. However, in order to identify ... Keywords: MPI-IO, Simulation, Tracing

Julian M. Kunkel

2013-05-01T23:59:59.000Z

466

Metrics for Parallel Job Scheduling and Their Convergence  

Science Journals Connector (OSTI)

The arrival process of jobs submitted to a parallel system is bursty, leading to fluctuations in the load at many time scales. In particular, rare events of extreme load may occur. Such events lead to an increase in the standard deviation of performance ...

Dror G. Feitelson

2001-06-01T23:59:59.000Z

467

Schubert and Macdonald Polynomials, a parallel Alain Lascoux  

E-Print Network (OSTI)

1 #12;Schubert and Macdonald Polynomials, a parallel Alain Lascoux 'oooooo 'oooooo 'oooooo 'oooooo Schubert and (non-symmetric) Macdonald polynomials are two lin- ear bases of the ring of polynomials which, x = {x1, . . . , xn}. Schubert polynomials {Yv : v Nn } and Macdonald polynomials {Mv : v Nn

Lascoux, Alain

468

Schubert and Macdonald Polynomials, a parallel Alain Lascoux  

E-Print Network (OSTI)

Schubert and Macdonald Polynomials, a parallel Alain Lascoux 'oooooo 'oooooo 'oooooo 'oooooo Schubert and (non-symmetric) Macdonald polynomials are two lin- ear bases of the ring of polynomials which, x = {x1, . . . , xn}. Schubert polynomials {Yv : v Nn } and Macdonald polynomials {Mv : v Nn

Lascoux, Alain

469

Parallel heat transport in integrable and chaotic magnetic fields  

SciTech Connect

The study of transport in magnetized plasmas is a problem of fundamental interest in controlled fusion, space plasmas, and astrophysics research. Three issues make this problem particularly chal- lenging: (i) The extreme anisotropy between the parallel (i.e., along the magnetic field), , and the perpendicular, , conductivities ( / may exceed 1010 in fusion plasmas); (ii) Magnetic field lines chaos which in general complicates (and may preclude) the construction of magnetic field line coordinates; and (iii) Nonlocal parallel transport in the limit of small collisionality. Motivated by these issues, we present a Lagrangian Green s function method to solve the local and non-local parallel transport equation applicable to integrable and chaotic magnetic fields in arbitrary geom- etry. The method avoids by construction the numerical pollution issues of grid-based algorithms. The potential of the approach is demonstrated with nontrivial applications to integrable (magnetic island chain), weakly chaotic (devil s staircase), and fully chaotic magnetic field configurations. For the latter, numerical solutions of the parallel heat transport equation show that the effective radial transport, with local and non-local closures, is non-diffusive, thus casting doubts on the appropriateness of the applicability of quasilinear diffusion descriptions. General conditions for the existence of non-diffusive, multivalued flux-gradient relations in the temperature evolution are derived.

Del-Castillo-Negrete, Diego B [ORNL; Chacon, Luis [ORNL

2012-01-01T23:59:59.000Z

470

Parallel algorithms for approximation of distance maps on parametric surfaces  

E-Print Network (OSTI)

results demonstrate up to four orders of magnitude improvement in execution time compared to the state(n) numerical algorithm for first-order approximation of geodesic distances on geometry images, where n charts, parallel algorithms, GPU, SIMD 1. INTRODUCTION Approximation of geodesic distances on curved

Kimmel, Ron

471

Full expandable model of parallel self-excited induction generators  

E-Print Network (OSTI)

for wind and small hydro power plants [1, 2]. They have advantages over conventional synchronous generators of wind power into power networks, an accurate dynamic model of the overall wind farm system is required to analyse the interaction between the wind farm and the power system. A system of parallel-operated SEIGs

Simões, Marcelo Godoy

472

Time parallelization of plasma simulations using the parareal algorithm  

SciTech Connect

Simulation of fusion plasmas involve a broad range of timescales. In magnetically confined plasmas, such as in ITER, the timescale associated with the microturbulence responsible for transport and confinement timescales vary by an order of 10^6 10^9. Simulating this entire range of timescales is currently impossible, even on the most powerful supercomputers available. Space parallelization has so far been the most common approach to solve partial differential equations. Space parallelization alone has led to computational saturation for fluid codes, which means that the walltime for computaion does not linearly decrease with the increasing number of processors used. The application of the parareal algorithm to simulations of fusion plasmas ushers in a new avenue of parallelization, namely temporal parallelization. The algorithm has been successfully applied to plasma turbulence simulations, prior to which it has been applied to other relatively simpler problems. This work explores the extension of the applicability of the parareal algorithm to ITER relevant problems, starting with a diffusion-convection model.

Samaddar, D. [ITER Organization, Saint Paul Lez Durance, France; Houlberg, Wayne A [ORNL; Berry, Lee A [ORNL; Elwasif, Wael R [ORNL; Huysmans, G [ITER Organization, Saint Paul Lez Durance, France; Batchelor, Donald B [ORNL

2011-01-01T23:59:59.000Z

473

Parallel Transient Dynamics Simulations: Algorithms for Contact Detection  

E-Print Network (OSTI)

February 5, 1998 Abstract Transient dynamics simulations are commonly used to model phenomena such as car and deform with the objects as they undergo stress. Fluids (gasoline, water) or fluid­ like materials (soil is a natural candidate for the power of parallel computers. Unfortunately, these kinds of simulations have

Plimpton, Steve

474

Green Computing Using Automatic Parallelizing and Power Reducing Compiler  

E-Print Network (OSTI)

. BG/Q (A2:16cores) Water Cooled20PFLOPS, 3-4MW (2011-12), BlueWaters(HPCS) Power7, 10 PFLOP+(2011Green Computing Using Automatic Parallelizing and Power Reducing Compiler with Multiplatform API (Embedded) Mobile Phone, Game, TV, Car Navigation, Camera, IBM/ Sony/ Toshiba Cell, Fujitsu FR1000

Kasahara, Hironori

475

PARALLEL COMPUTATION OF THE BOLTZMANN TRANSPORT EQUATION FOR MICROSCALE HEAT  

E-Print Network (OSTI)

silicon ðSi� and silicon dioxide ðSiO2�. The equation of phonon radiative transport ðERPT�, in itsPARALLEL COMPUTATION OF THE BOLTZMANN TRANSPORT EQUATION FOR MICROSCALE HEAT TRANSFER fundamental Boltzmann transport equations have been reported [3, 7, 8]. This has consequently instigated a re

Miller, Richard S.

476

Models and Algorithms for Optical and Optoelectronic Parallel Computers  

E-Print Network (OSTI)

Models and Algorithms for Optical and Optoelectronic Parallel Computers Sartaj Sahni Dept/Fremantle, Australia #12;realization leads to the concept of optoelectronic computers­computers which have a mix the prespective of efficient algorithm design. The OTIS family of optoelectronic computers is a step

Sahni, Sartaj K.

477

Parallel memory prediction for fused linear algebra kernels  

Science Journals Connector (OSTI)

The performance of many scientific programs is limited by data movement. Loop fusion is one optimization used to increase the speed of memory bound operations. To automate loop fusion for matrix computations, we developed the Build to Order (BTO) compiler. ... Keywords: auto-tuning, memory modeling, parallel processing

Ian Karlin; Elizabeth Jessup; Geoffrey Belter; Jeremy G. Siek

2011-03-01T23:59:59.000Z

478

OSCAR Compiler for Automatic Parallelization and Power Reduction  

E-Print Network (OSTI)

of coarse grain tasks acro-tasks (MTs) Block of Pseudo Assignments (BPA): Basic Block (BB) Repetition Block (RB) : natural loop Subroutine Block (SB): subroutine Program BPA RB SB Near fine grain parallelization BPA RB SB BPA RB SB BPA RB SB BPA RB SB BPA RB SB BPA RB SB 1st. Layer 2nd. Layer 3rd. Layer Total

Kasahara, Hironori

479

Simultaneous Scheduling and Control of Multiproduct Continuous Parallel Lines  

E-Print Network (OSTI)

continuous reactors is cast as a Mixed-Integer Dynamic Optimization (MIDO) problem. The reactor dynamic;Abstract In this work we propose a simultaneous scheduling and control optimization formulation to ad- dress both optimal steady-state production and dynamic product transitions in multiproduct parallel

Grossmann, Ignacio E.

480

A MICROFLUIDIC BIOCHIP DEDICATED TO HIGHLY PARALLELIZED ELECTROFUSION  

E-Print Network (OSTI)

0065 A MICROFLUIDIC BIOCHIP DEDICATED TO HIGHLY PARALLELIZED ELECTROFUSION F. Hamdi1, 2 , O: Microfluidics, Biochip, Electrofusion, Cell trapping INTRODUCTION The electrofusion between a dendritic i) the trapping of cells flowing in the microfluidic channel ii) their pairing prior to fusion, iii

Paris-Sud XI, Université de

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481

Performance of Parallel Eigensolvers on Electronic Structure Calculations II  

E-Print Network (OSTI)

Performance of Parallel Eigensolvers on Electronic Structure Calculations II Robert C. Ward1 employed to solve problems in quantum mechanics, such as electronic structure calculations, result in both symmetric linear eigensolvers applied to such eigenproblems in electronic structure calculations on the IBM

Ward, Robert C.

482

Performance of Parallel Eigensolvers on Electronic Structure Calculations  

E-Print Network (OSTI)

Performance of Parallel Eigensolvers on Electronic Structure Calculations Robert C. Ward*§ , Yihua. Many models employed to solve problems in quantum mechanics, such as electronic structure calculations-Consistent Field procedure in electronic structure calculations on the distributed memory supercomputers at the Oak

Ward, Robert C.

483

Measurements of parallel electron velocity distributions using whistler wave absorption  

SciTech Connect

We describe a diagnostic to measure the parallel electron velocity distribution in a magnetized plasma that is overdense ({omega}{sub pe} > {omega}{sub ce}). This technique utilizes resonant absorption of whistler waves by electrons with velocities parallel to a background magnetic field. The whistler waves were launched and received by a pair of dipole antennas immersed in a cylindrical discharge plasma at two positions along an axial background magnetic field. The whistler wave frequency was swept from somewhat below and up to the electron cyclotron frequency {omega}{sub ce}. As the frequency was swept, the wave was resonantly absorbed by the part of the electron phase space density which was Doppler shifted into resonance according to the relation {omega}-k{sub ||v||} = {omega}{sub ce}. The measured absorption is directly related to the reduced parallel electron distribution function integrated along the wave trajectory. The background theory and initial results from this diagnostic are presented here. Though this diagnostic is best suited to detect tail populations of the parallel electron distribution function, these first results show that this diagnostic is also rather successful in measuring the bulk plasma density and temperature both during the plasma discharge and into the afterglow.

Thuecks, D. J.; Skiff, F.; Kletzing, C. A. [Department of Physics and Astronomy, University of Iowa, 203 Van Allen Hall, Iowa City, Iowa 52242 (United States)

2012-08-15T23:59:59.000Z

484

Parallel Processing Letters fc World Scientific Publishing Company  

E-Print Network (OSTI)

Parallel Processing Letters fc World Scientific Publishing Company SCHEDULING ISSUES Department, University of Idaho Moscow, Idaho 83844-1010, USA and AZAD AZADMANESH Computer Science Department, University of Nebraska at Omaha Omaha, Nebraska 68182-0500, USA and MILES McQUEEN Idaho National Engineering

Krings, Axel W.

485

GMATE: Dynamic Tuning of Parallel Applications in Grid Environment  

Science Journals Connector (OSTI)

Performance is a main issue in parallel application development. Dynamic tuning is a technique that changes certain applications' parameters on-line to improve their performance adapting the execution to actual conditions. To perform that, it is necessary ... Keywords: Computational Grid, Dynamic tuning, Performance model

Genaro Costa, Anna Sikora, Josep Jorba, Tomàs Margalef

2014-06-01T23:59:59.000Z

486

Application of Parallel Processing to Intelligent Control of Mobile Robots  

E-Print Network (OSTI)

to meetfuture needs. Key words: Mobile Robots, Parallel Processing, Intelligent Control, Architecture. 1 to navigate its environment, build or update maps, plan and execute actions, and adapt its behaviour to envir requires multi-processorarchitectures to bear the burden of processing loads. Such computer architectures

Hu, Huosheng

487

AUTOMATIC PARALLELIZATION OF OBJECT ORIENTED MODELS ACROSS METHOD AND  

E-Print Network (OSTI)

and Modelica Modelica is a rather new language for equation-based object-oriented mathematical modeling which object- oriented modeling languages. Modelica is intended to become a de facto standard. It allowsAUTOMATIC PARALLELIZATION OF OBJECT ORIENTED MODELS ACROSS METHOD AND SYSTEM HÃ¥kan Lundvall

Zhao, Yuxiao

488

An approach to parallelizing the simulation of complicated modelica models  

Science Journals Connector (OSTI)

Designing embedded systems has become a complex and expensive task, and simulation and other analysis tools are taking on a bigger role in the overall design process. In an effort to speed up the design process, we present an algorithm for reducing the ... Keywords: directed acyclic graph, efficient simulation models, equation-based modeling, parallel scheduling

Joshua D. Carl, Gautam Biswas, Sandeep Neema, Ted Bapty

2014-07-01T23:59:59.000Z

489

All Optical Interface for Parallel, Remote, and Spatiotemporal Control of  

E-Print Network (OSTI)

All Optical Interface for Parallel, Remote, and Spatiotemporal Control of Neuronal Activity Sheng and detection of activity in a large number of neurons. Here, we report an all-optical system for achieving optical stimuli through a digital micromirror spatiotemporal light modulator to cells expressing the light

Trauner, Dirk

490

Verification of Parallel Garbage Collection by Abstract Model Checking  

E-Print Network (OSTI)

have a finite state space provided that the abstraction mapping is powerful. M¨uller and Nipkow's work working on abstract model checking. In Section 4, the abstractions we defined on garbage #12; collectionVerification of Parallel Garbage Collection by Abstract Model Checking (Extended Abstract) Masami

Hagiya, Masami

491

Parallel and Adaptive Simulation of Fuel Cells Robert Klfkorn1  

E-Print Network (OSTI)

Parallel and Adaptive Simulation of Fuel Cells in 3d Robert Klöfkorn1 , Dietmar Kröner1 , Mario) fuel cells. Hereby, we focus on the simulation done in 3d us- ing modern techniques like higher order and the transport of species in the cathodic gas diffusion layer of the fuel cell. Therefore, from the detailed

Münster, Westfälische Wilhelms-Universität

492

Nested Loop Algorithm for Parallel Model Based Iterative Reconstruction  

E-Print Network (OSTI)

Nested Loop Algorithm for Parallel Model Based Iterative Reconstruction Zhou Yu, Lin Fu, Debashish. In this paper, we propose a fast converging simultaneous-update algorithm using a nested loop structure tomography, iterative reconstruction, nested loop, preconditioner. I. INTRODUCTION Recent applications

493

A parallel algorithm for 3D dislocation dynamics  

SciTech Connect

Dislocation dynamics (DD), a discrete dynamic simulation method in which dislocations are the fundamental entities, is a powerful tool for investigation of plasticity, deformation and fracture of materials at the micron length scale. However, severe computational difficulties arising from complex, long-range interactions between these curvilinear line defects limit the application of DD in the study of large-scale plastic deformation. We present here the development of a parallel algorithm for accelerated computer simulations of DD. By representing dislocations as a 3D set of dislocation particles, we show here that the problem of an interacting ensemble of dislocations can be converted to a problem of a particle ensemble, interacting with a long-range force field. A grid using binary space partitioning is constructed to keep track of node connectivity across domains. We demonstrate the computational efficiency of the parallel micro-plasticity code and discuss how O(N) methods map naturally onto the parallel data structure. Finally, we present results from applications of the parallel code to deformation in single crystal fcc metals.

Wang Zhiqiang [University of California - Los Angeles, Los Angeles, CA 90095-1597 (United States)]. E-mail: zhiqiang@lanl.gov; Ghoniem, Nasr [University of California - Los Angeles, Los Angeles, CA 90095-1597 (United States); Swaminarayan, Sriram [University of California, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); LeSar, Richard [University of California, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2006-12-10T23:59:59.000Z

494

Energy-Efficient Sensing and Communication of Parallel Gaussian Sources  

E-Print Network (OSTI)

Energy-Efficient Sensing and Communication of Parallel Gaussian Sources Xi Liu, Osvaldo Simeone to be operated in an energy-efficient manner in order to attain a satisfactory lifetime. Energy consumption efficiency [2] [3]. We refer to the energy cost associated with measurements and compression of information

Erkip, Elza

495

Xyce Parallel Electronic Simulator Users Guide Version 6.2.  

SciTech Connect

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been de- signed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel com- puting platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one to develop new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandia's needs, including some radiation- aware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase -- a message passing parallel implementation -- which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows. Trademarks The information herein is subject to change without notice. Copyright c 2002-2014 Sandia Corporation. All rights reserved. Xyce TM Electronic Simulator and Xyce TM are trademarks of Sandia Corporation. Portions of the Xyce TM code are: Copyright c 2002, The Regents of the University of California. Produced at the Lawrence Livermore National Laboratory. Written by Alan Hindmarsh, Allan Taylor, Radu Serban. UCRL-CODE-2002-59 All rights reserved. Orcad, Orcad Capture, PSpice and Probe are registered trademarks of Cadence Design Systems, Inc. Microsoft, Windows and Windows 7 are registered trademarks of Microsoft Corporation. Medici, DaVinci and Taurus are registered trademarks of Synopsys Corporation. Amtec and TecPlot are trademarks of Amtec Engineering, Inc. Xyce 's expression library is based on that inside Spice 3F5 developed by the EECS Department at the University of California. The EKV3 MOSFET model was developed by the EKV Team of the Electronics Laboratory-TUC of the Technical University of Crete. All other trademarks are property of their respective owners. Contacts Bug Reports (Sandia only) http://joseki.sandia.gov/bugzilla http://charleston.sandia.gov/bugzilla World Wide Web http://xyce.sandia.gov http://charleston.sandia.gov/xyce (Sandia only) Email xyce%40sandia.gov (outside Sandia) xyce-sandia%40sandia.gov (Sandia only)

Keiter, Eric R.; Mei, Ting; Russo, Thomas V.; Schiek, Richard; Sholander, Peter E.; Thornquist, Heidi K.; Verley, Jason; Baur, David Gregory

2014-09-01T23:59:59.000Z

496

Power Management Strategy for a Parallel Hybrid Electric Truck Power Management Strategy for a Parallel Hybrid Electric Truck  

E-Print Network (OSTI)

. The design procedure starts by defining a cost function, such as minimizing a combination of fuel consumption of a small increase in fuel consumption. #12;Power Management Strategy for a Parallel Hybrid Electric Truck I. INTRODUCTION Medium and heavy trucks running on diesel engines serve an important role in modern societies

Grizzle, Jessy W.

497

GIS Applications in MeteorologyGIS Applications in Meteorology Adventures in a Parallel UniverseAdventures in a Parallel Universe  

E-Print Network (OSTI)

GIS Applications in MeteorologyGIS Applications in Meteorology (or)(or) Adventures in a Parallel Mason UniversityDept. Geography, George Mason University 24 June 200324 June 2003 GIS Meteorology, Shipley NCAR, 24 Jun 2003NCAR 24Jun03.ppt #12;NCAR 24Jun03.ppt GIS Meteorology, Shipley NCAR, 24 Jun 2003

498

The Death of a Massive Star Holds Key to Early Universe | U.S. DOE Office  

Office of Science (SC) Website

The Death of The Death of a Massive Star Holds Key to Early Universe News Featured Articles 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Presentations & Testimony News Archives Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 12.16.09 The Death of a Massive Star Holds Key to Early Universe Scientists found the remains of a massive star, providing them with new information to reassess the environment of the early Universe. Print Text Size: A A A Subscribe FeedbackShare Page Imagine if paleontologists found the fossilized remains of a long-hypothesized, but never discovered dinosaur deep in the Amazon rainforest. Well, physicists participating in the international Supernova Factory, a Department of Energy sponsored project at Lawrence Berkeley

499

Massive Energy Storage in Superconductors (SMES) | U.S. DOE Office of  

NLE Websites -- All DOE Office Websites (Extended Search)

Massive Energy Storage in Superconductors (SMES) Massive Energy Storage in Superconductors (SMES) Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » August 2013 Massive Energy Storage in Superconductors (SMES) Novel high temperature superconductor magnet technology charts new territory. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Image courtesy of Brookhaven National Laboratory A toroid SMES system consisting of a number of high field coils made with

500

New Mariners and a Massive Map: Berkeley Computers Calculate What's in the  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Mariners and a Massive Map: Berkeley Computers Calculate What's Mariners and a Massive Map: Berkeley Computers Calculate What's in the Sky New Mariners and a Massive Map: Berkeley Computers Calculate What's in the Sky February 2, 2012 - 12:08pm Addthis This is the Southern Galactic Cap view as recorded by the Sloan Digital Sky Survey. A 2.5-meter telescope at Apache Point Observatory in New Mexico took in light from over a third of the total area of the sky (14,000 square degrees) including 1.5 million galaxies. | Photo courtesy of the Sloan Digital Sky Survey. This is the Southern Galactic Cap view as recorded by the Sloan Digital Sky Survey. A 2.5-meter telescope at Apache Point Observatory in New Mexico took in light from over a third of the total area of the sky (14,000 square degrees) including 1.5 million galaxies. | Photo courtesy of the Sloan