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ActiveSpaces on the Grid: The Construction of Advanced Visualization and Interaction Environments (open access)

ActiveSpaces on the Grid: The Construction of Advanced Visualization and Interaction Environments

The Futures Lab group at Argonne National Laboratory and the University of Chicago are designing, building, and evaluating a new type of interactive computing environment that couples in a deep way the concepts of direct manipulation found in virtual reality with the richness and variety of interactive devices found in ubiquitous computing. This environment provides the interactivity and collaboration support of teleimmersive environments with the exibility and availability of desktop collaboration tools. The authors call these environments ActiveSpaces. An ActiveSpace is a physical domain that has been augmented with multiscale multiscreen displays, environment-specific and device-specific sensors, body and object trackers, human-input and instrument-input interfaces, streaming audio and video capture devices, and force feedback devices--and has then been connected to other such spaces via the Grid.
Date: July 24, 2000
Creator: Childers, Lisa; Disz, Terry; Hereld, Mark; Hudson, Randy; Judson, Ivan; Olson, Robert et al.
Object Type: Article
System: The UNT Digital Library
All Solid State Optical Pulse Shaper for the OMEGA Laser Fusion Facility (open access)

All Solid State Optical Pulse Shaper for the OMEGA Laser Fusion Facility

OAK-B135 All Solid State Optical Pulse Shaper for the OMEGA Laser Fusion Facility. The authors have developed an all-solid-state, compact, computer-controlled, flexible optical pulse shaper for the OMEGA laser facility. This pulse shaper produces high bandwidth, temporally shaped laser pulses that meet OMEGA requirements. The design is a significant simplification over existing technology with improved performance capabilities.
Date: July 24, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 101, No. 115, Ed. 1 Monday, July 24, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 101, No. 115, Ed. 1 Monday, July 24, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 24, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 109, No. 60, Ed. 1 Monday, July 24, 2000 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 109, No. 60, Ed. 1 Monday, July 24, 2000

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: July 24, 2000
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Angular Sensitivity of Gated Micro-Channel Plate Framing Cameras (open access)

Angular Sensitivity of Gated Micro-Channel Plate Framing Cameras

Gated, microchannel-plate-based (MCP) framing cameras have been deployed worldwide for 0.2 - 9 keV x-ray imaging and spectroscopy of transient plasma phenomena. For a variety of spectroscopic and imaging applications, the angular sensitivity of MCPs must be known for correctly interpreting the data. We present systematic measurements of angular sensitivity at discrete relevant photon energies and arbitrary MCP gain. The results can been accurately predicted by using a simple 2D approximation to the 3D MCP geometry and by averaging over all possible photon ray paths.
Date: July 24, 2000
Creator: Landen, O L; Lobban, A; Tutt, T; Bell, P M; Costa, R & Ze, F
Object Type: Article
System: The UNT Digital Library
Army Corps of Engineers: An Assessment of the Draft Environmental Impact Statement of the Lower Snake River Dams (open access)

Army Corps of Engineers: An Assessment of the Draft Environmental Impact Statement of the Lower Snake River Dams

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Army Corps of Engineers' environmental impact statement (EIS) of the Lower Snake River dams, focusing on: (1) extent to which the Corps followed applicable procedures and guidelines in preparing the draft EIS; and (2) reasonableness of the methodology the Corps used to analyze and present the effects of breaching the dams, specifically with respect to electricity costs, transportation costs, and air quality."
Date: July 24, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
The ASCI Network for SC '99: A Step on the Path to a 100 Gigabit Per Second Supercomputing Network (open access)

The ASCI Network for SC '99: A Step on the Path to a 100 Gigabit Per Second Supercomputing Network

This document highlights the Discom{sup 2}'s Distance computing and communication team activities at the 1999 Supercomputing conference in Portland, Oregon. This conference is sponsored by the IEEE and ACM. Sandia, Lawrence Livermore and Los Alamos National laboratories have participated in this conference for eleven years. For the last four years the three laboratories have come together at the conference under the DOE's ASCI, Accelerated Strategic Computing Initiatives rubric. Communication support for the ASCI exhibit is provided by the ASCI DISCOM{sup 2} project. The DISCOM{sup 2} communication team uses this forum to demonstrate and focus communication and networking developments within the community. At SC 99, DISCOM built a prototype of the next generation ASCI network demonstrated remote clustering techniques, demonstrated the capabilities of the emerging Terabit Routers products, demonstrated the latest technologies for delivering visualization data to the scientific users, and demonstrated the latest in encryption methods including IP VPN technologies and ATM encryption research. The authors also coordinated the other production networking activities within the booth and between their demonstration partners on the exhibit floor. This paper documents those accomplishments, discusses the details of their implementation, and describes how these demonstrations support Sandia's overall strategies in ASCI networking.
Date: July 24, 2000
Creator: Pratt, Thomas J.; Tarman, Thomas D.; Martinez, Luis M.; Miller, Marc M.; Adams, Roger L.; Chen, Helen Y. et al.
Object Type: Report
System: The UNT Digital Library
Assessment of the teledial gas-cooled transmuter concept (open access)

Assessment of the teledial gas-cooled transmuter concept

The application of four gas-turbine, modular helium cooled reactors and an accelerator unit (GT/AD-MHR) has been proposed for burning transuranics recycled from LWR waste. The recycled LWR discharged transuranics encapsulated in TRISO coated particles are first loaded into the outer thermal spectrum zone of the GT/AD-MHR for burning in the critical mode for about three years. Previously burned fuel is in a central fast zone. In the fourth year, the same unit is configured as an accelerator-driven system, containing a centrally located spallation target. The three-year, thermal-zone burned fuel and the inner fast-zone fuel from the critical mode operation are used in this subcritical cycle, and remain in their respective zones. At the end of this one-year subcritical irradiation, the outer thermal-zone fuel is reconstituted and used as fast-zone fuel in another critical mode operation. As the fuel in the fast-zone has reached its end of life it is discharged, with very low transuranics content. The critical mode operation is staggered, and each GT/AD-MGR unit undergoes the subcritical burn in one out of four year. The physics performance of the GT/AD-MHR has been evaluated using independent deterministic and Monte Carlo codes and the results of the study are presented in …
Date: July 24, 2000
Creator: Taiwo, T. A.; Gohar, Y. & Finck, P. J.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 241, Ed. 1 Monday, July 24, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 78, No. 241, Ed. 1 Monday, July 24, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 24, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Condition Monitoring of a Thermally Aged HTPB/IPDI Elastomer by NMR CP Recovery Times (open access)

Condition Monitoring of a Thermally Aged HTPB/IPDI Elastomer by NMR CP Recovery Times

A hydroxy-terminated polybutadiene (HTPB)/isophorone diisocyanate (IPDI) elastomer is commonly used as propellant binder material. The thermal degradation of the binder is believed to be an important parameter governing the performance of the propellant. The aging of these binders can be monitored by mechanical property measurements such as modulus or tensile elongation. These techniques, however, are not easily adapted to binder agents that are dispersed throughout a propellant. In this paper the authors investigated solid state NMR relaxation times as a means to predict the mechanical properties of the binder as a function of aging time. {sup 1}H spin-lattice and spin-spin relaxation times were found to be insensitive to the degree of thermal degradation of the elastomer. Apparently these relaxation times depend on localized motions that are only weakly correlated with mechanical properties. A strong correlation was found between the {sup 13}C cross-polarization (CP) NMR time constant, T{sub cp}, and the tensile elongation at break of the elastomer as a function of aging time. A ramped-amplitude CP experiment was shown to be less sensitive to imperfections in setting critical instrumental parameters for this mobile material.
Date: July 24, 2000
Creator: Assink, Roger A.; Lang, David & Celina, Mathias C.
Object Type: Article
System: The UNT Digital Library
Continuum strong QCD: Confinement and dynamical chiral symmetry breaking (open access)

Continuum strong QCD: Confinement and dynamical chiral symmetry breaking

Continuum strong QCD is the application of models and continuum quantum field theory to the study of phenomena in hadronic physics, which includes; e.g., the spectrum of QCD bound states and their interactions. Herein the author provides a Dyson-Schwinger equation perspective, focusing on qualitative aspects of confinement and dynamical chiral symmetry breaking in cold, sparse QCD, and also elucidating consequences of the axial-vector Ward-Takahashi identity and features of the heavy-quark limit.
Date: July 24, 2000
Creator: Roberts, C. D.
Object Type: Article
System: The UNT Digital Library
DART's Cowboy Flyer Moves Through Traffic Like Rocket Ismail Through the Redskins' Secondary (open access)

DART's Cowboy Flyer Moves Through Traffic Like Rocket Ismail Through the Redskins' Secondary

News release about the "Cowboy Flyer," a bus service to Dallas Cowboy games.
Date: July 24, 2000
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Defects at the carbon terminated SiC (001) surface (open access)

Defects at the carbon terminated SiC (001) surface

We present first principle molecular dynamics simulations for selected point defects on the (001) stoichiometric carbon terminated surface of cubic Silicon Carbide. In particular we investigated missing units and coordination defects. The results of our calculations are compared with recent experiments, in particular we discuss simulated STM images, which are in good agreement with measured ones.
Date: July 24, 2000
Creator: Catellani, A & Galli, G
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT OF HIGH ACTIVITY, COAL-DERIVED, PROMOTED CATALYTIC SYSTEMS FOR NOx REDUCTION AT LOW TEMPERATURES (open access)

DEVELOPMENT OF HIGH ACTIVITY, COAL-DERIVED, PROMOTED CATALYTIC SYSTEMS FOR NOx REDUCTION AT LOW TEMPERATURES

This project is directed at an investigation of catalytic NO{sub x} reduction mechanisms on coal-derived, activated carbon supports at low temperatures. Promoted carbon systems offer some potentially significant advantages for heterogeneous NO{sub x} reduction. These include: low cost; high activity at low temperatures, which minimizes carbon loss; oxygen resistance; and a support material which can be engineered with respect to porosity, transport and catalyst dispersion characteristics. During the reporting period, TPD studies were conducted following steady-state reaction in NO/CO mixtures in helium. From these studies, the following points have been concluded: (1) The total amount of CO and N{sub 2} evolved following reaction in NO increases with reaction temperature. The TPD spectra are skewed to high temperatures, indicating more stable surface complexes with high desorption activation energies. (2) The total amount of CO evolved following exposure of the char sample to CO at reaction temperatures decreases with reaction temperature, similar to chemisorption behavior. The CO TPD spectra are shifted to lower temperatures, indicating more labile oxygen surface complexes with lower desorption activation energies. (3) The total amount of CO evolved following reaction in NO/CO mixtures decreases with reaction temperature, while the evolved N{sub 2} still increases with reaction temperature. The …
Date: July 24, 2000
Creator: Calo, Joseph M.
Object Type: Report
System: The UNT Digital Library
Dynamic Software Testing of MPI Applications with Umpire (open access)

Dynamic Software Testing of MPI Applications with Umpire

As evidenced by the popularity of MPI (Message Passing Interface), message passing is an effective programming technique for managing coarse-grained concurrency on distributed computers. Unfortunately, debugging message-passing applications can be difficult. Software complexity, data races, and scheduling dependencies can make programming errors challenging to locate with manual, interactive debugging techniques. This article describes Umpire, a new tool for detecting programming errors at runtime in message passing applications. Umpire monitors the MPI operations of an application by interposing itself between the application and the MPI runtime system using the MPI profiling layer. It, then, checks its MPI behavior for specific errors. The initial collection of programming errors includes deadlock detection, mismatched collective operations, and resource exhaustion. They present an evaluation that demonstrates the effectiveness of this approach.
Date: July 24, 2000
Creator: Vetter, J & de Supinski, B
Object Type: Article
System: The UNT Digital Library
Electricity Restructuring: Comparison of Comprehensive Bills (open access)

Electricity Restructuring: Comparison of Comprehensive Bills

Once considered the nation's most regulated industry, the electric utility industry is evolving into a more competitive environment. Currently, the focus of this development is the generating sector, where the advent of new generating technologies has lowered both entry barriers to competitors of traditional utilities and the marginal costs of those competitors below those of some traditional utilities. This technological advance has combined with legislative initiatives, such as the Energy Policy Act (EPACT), to encourage the introduction of competitive forces into the electric generating sector.
Date: July 24, 2000
Creator: Parker, Larry & Abel, Amy
Object Type: Report
System: The UNT Digital Library
Elliptic Solvers with Adaptive Mesh Refinement on Complex Geometries (open access)

Elliptic Solvers with Adaptive Mesh Refinement on Complex Geometries

Adaptive Mesh Refinement (AMR) is a numerical technique for locally tailoring the resolution computational grids. Multilevel algorithms for solving elliptic problems on adaptive grids include the Fast Adaptive Composite grid method (FAC) and its parallel variants (AFAC and AFACx). Theory that confirms the independence of the convergence rates of FAC and AFAC on the number of refinement levels exists under certain ellipticity and approximation property conditions. Similar theory needs to be developed for AFACx. The effectiveness of multigrid-based elliptic solvers such as FAC, AFAC, and AFACx on adaptively refined overlapping grids is not clearly understood. Finally, a non-trivial eye model problem will be solved by combining the power of using overlapping grids for complex moving geometries, AMR, and multilevel elliptic solvers.
Date: July 24, 2000
Creator: Phillip, B.
Object Type: Article
System: The UNT Digital Library
Energy-economy interactions revisited within a comprehensive sectoral model (open access)

Energy-economy interactions revisited within a comprehensive sectoral model

This paper describes a computable general equilibrium (CGE) model with considerable sector and technology detail, the ``All Modular Industry Growth Assessment'' Model (AMIGA). It is argued that a detailed model is important to capture and understand the several rolls that energy plays within the economy. Fundamental consumer and industrial demands are for the services from energy; hence, energy demand is a derived demand based on the need for heating, cooling mechanical, electrical, and transportation services. Technologies that provide energy-services more efficiently (on a life cycle basis), when adopted, result in increased future output of the economy and higher paths of household consumption. The AMIGA model can examine the effects on energy use and economic output of increases in energy prices (e.g., a carbon charge) and other incentive-based policies or energy-efficiency programs. Energy sectors and sub-sector activities included in the model involve energy extraction conversion and transportation. There are business opportunities to produce energy-efficient goods (i.e., appliances, control systems, buildings, automobiles, clean electricity). These activities are represented in the model by characterizing their likely production processes (e.g., lighter weight motor vehicles). Also, multiple industrial processes can produce the same output but with different technologies and inputs. Secondary recovery, i.e., recycling processes, …
Date: July 24, 2000
Creator: Hanson, D. A. & Laitner, J. A.
Object Type: Article
System: The UNT Digital Library
Enhancement of Dilute-Acid Total-Hydrolysis Process for High-Yield Saccharification of Cellulosic Biomass (open access)

Enhancement of Dilute-Acid Total-Hydrolysis Process for High-Yield Saccharification of Cellulosic Biomass

None
Date: July 24, 2000
Creator: Lee, Y. Y.; Xiang, Qian; Kim, Tae-Hyun & Kim, Junseok
Object Type: Report
System: The UNT Digital Library
Experiments at The Virtual National Laboratory for Heavy Ion Fusion (open access)

Experiments at The Virtual National Laboratory for Heavy Ion Fusion

An overview of experiments is presented, in which the physical dimensions, emittance and perveance are scaled to explore driver-relevant beam dynamics. Among these are beam merging, focusing to a small spot, and bending and recirculating beams. The Virtual National Laboratory for Heavy Ion Fusion (VNL) is also developing two driver-scale beam experiments involving heavy-ion beams with I(sub beam) about 1 Ampere to provide guidance for the design of an Integrated Research Experiment (IRE) for driver system studies within the next 5 years. Multiple-beam sources and injectors are being designed and a one-beam module will be built and tested. Another experimental effort will be the transport of such a beam through about 100 magnetic quadrupoles. The experiment will determine transport limits at high aperture fill factors, beam halo formation, and the influence on beam properties of secondary electron Research into driver technology will be briefly presented, including the development of ferromagnetic core materials, induction core pulsers, multiple-beam quadrupole arrays and plasma channel formation experiments for pinched transport in reactor chambers.
Date: July 24, 2000
Creator: Seidl, P. A.; Bieniosek, F. M.; Celata, C. M.; Faltens, A.; Kwan, J. W.; MacLaren, S. A. et al.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 24, 2000 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 24, 2000

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 24, 2000
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Final report on the National Conference of State Legislatures project 'Assistance to State Legislatures on Alternative Fuel Vehicle Issues' (open access)

Final report on the National Conference of State Legislatures project 'Assistance to State Legislatures on Alternative Fuel Vehicle Issues'

This report assesses the effectiveness of state alternative fuel vehicle incentives and suggests incentives that might encourage new vehicle technologies. It does not assess whether a state should promote alternative fuel vehicles or whether such vehicles are the most effective means to reduce air pollution.
Date: July 24, 2000
Creator: Brown, Matthew & Sundeen, Matt
Object Type: Report
System: The UNT Digital Library
A high-precision cryogenically-cooled crystal monochromator for the APS diagnostics beamline (open access)

A high-precision cryogenically-cooled crystal monochromator for the APS diagnostics beamline

A high-precision cryogenically-cooled crystal monochromator has been developed for the APS diagnostics beamline. The design permits simultaneous measurements of the particle beam size and divergence. It provides for a large rotation angle, {minus}15{degree} to 180{degree}, with a resolution of 0.0005{degree}. The roll angle of the crystal can be adjusted by up to {+-}3{degree} with a resolution of 0.0001{degree}. A vertical translational stage, with a stroke of {+-}25 mm and resolution of 8 {micro}m, is provided to enable using different parts of the same crystal or to retract the crystal from the beam path. The modular design will allow optimization of cooling schemes to minimize thermal distortions of the crystal under high heat loads.
Date: July 24, 2000
Creator: Rotela, E.; Yang, B.; Sharma, S. & Barcikowski, A.
Object Type: Article
System: The UNT Digital Library
Homelessness: HUD Funds Eligible Projects According to Communities' Priorities (open access)

Homelessness: HUD Funds Eligible Projects According to Communities' Priorities

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Housing and Urban Development's (HUD) funding of Stewart B. McKinney Homeless Assistance Act projects, focusing on: (1) what process HUD uses to select projects for funding, whether this process is consistent with relevant statutes, and how HUD treats new projects and projects that have been funded in the past (renewal projects); (2) the extent to which HUD funds projects that communities rank as high-priority under their Continuums of Care, and why some high-priority projects are not funded while some low-priority projects are funded; and (3) whether communities face any common problems when applying for funds from HUD, and what actions are needed to correct these problems."
Date: July 24, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library