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Prospecting for lunar ice using a multi-rover cooperative team

Description: A multi-rover cooperative team or swarm developed by Sandia National Laboratories is described, including various control methodologies that have been implemented to date. How the swarm's capabilities could be applied to a lunar ice prospecting mission is briefly explored. Some of the specific major engineering issues that must be addressed to successfully implement the swarm approach to a lunar surface mission are outlined, and potential solutions are proposed.
Date: February 11, 2000
Creator: Klarer, Paul R.; Feddema, John T. & Lewis, Christopher L.
Partner: UNT Libraries Government Documents Department
open access

Optimal Segmentation Strategy for Compact Representation of Hyperspectral Image Cubes

Description: By producing compact representations of hyperspectral image cubes (hypercubes), image storage requirements and the amount of time it takes to extract essential elements of information can both be dramatically reduced. However, these compact representations must preserve the important spectral features within hypercube pixels and the spatial structure associated with background and objects or phenomena of interest. This paper describes a novel approach for automatically and efficiently generatin… more
Date: February 8, 2000
Creator: Paglieroni, D & Roberts, R
Partner: UNT Libraries Government Documents Department
open access

Molecular dynamics simulation of cascade damage in gold

Description: High-energy cascades have been simulated in gold using molecular dynamics with a modified embedded atom method potential. The results show that both vacancy and interstitial clusters form with high probability as a result of intracascade processes. The formation of clusters has been interpreted in terms of the high pressures generated in the core of the cascade during the early stages. We provide evidence that correlation between interstitial and vacancy clustering exists.
Date: February 1, 2000
Creator: Alonso, E.; Caturla, M. J.; Tang, M.; Huang, H. & Diaz de la Rubia, T
Partner: UNT Libraries Government Documents Department
open access

Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet

Description: A 'proof-of-principle' Nb{sub 3}Sn superconducting dual-bore dipole magnet was built from racetrack coils, as a first step in a program to develop an economical, 15 Tesla, accelerator-quality magnet. The mechanical design and magnet fabrication procedures are discussed. No training was required to achieve temperature-dependent plateau currents, despite several thermal cycles that involved partial magnet disassembly and substantial pre-load variations. Subsequent magnets are expected to approach… more
Date: February 6, 2000
Creator: Chow, K.; Dietderich, D. R.; Gourlay, S. A.; Gupta, R.; Harnden, W.; Lietzke, A. F. et al.
Partner: UNT Libraries Government Documents Department
open access

AZU-1: A Candidate Breast Tumor Suppressor and Biomarker for Tumor Progression

Description: To identify genes misregulated in the final stages of breast carcinogenesis, we performed differential display to compare the gene expression patterns of the human tumorigenic mammary epithelial cells, HMT-3522-T4-2, with those of their immediate premalignant progenitors, HMT-3522-S2. We identified a novel gene, called anti-zuai-1 (AZU-1), that was abundantly expressed in non- and premalignant cells and tissues but was appreciably reduced in breast tumor cell types and in primary tumors. The AZ… more
Date: February 4, 2000
Creator: Chen, Huei-Mei; Schmeichel, Karen L; Mian, I. Saira; Lelie`vre, Sophie; Petersen, Ole W & Bissell, Mina J
Partner: UNT Libraries Government Documents Department
open access

MSW Effects in Vacuum Oscillations

Description: We point out that for solar neutrino oscillations with the mass-squared difference of Delta m^2 ~;; 10^-10 - 10^-9 eV^2, traditionally known as"vacuum oscillation'' range, the solar matter effects are non-negligible, particularly for the low energy pp neutrinos. One consequence of this is that the values of the mixing angle theta and pi/2-theta are not equivalent, leading to the need to consider the entire physical range of the mixing angle 0<=theta<=pi/2 when determining the allowed… more
Date: February 6, 2000
Creator: Friedland, Alexander
Partner: UNT Libraries Government Documents Department
open access

Quantum mechanical cluster calculations of critical scintillationprocesses

Description: This paper describes the use of commercial quantum chemistrycodes to simu-late several critical scintillation processes. The crystalis modeled as a cluster of typically 50 atoms embedded in an array oftypically 5,000 point charges designed to reproduce the electrostaticfield of the infinite crystal. The Schrodinger equation is solved for theground, ionized, and excited states of the system to determine the energyand electron wavefunction. Computational methods for the followingcritical processe… more
Date: February 22, 2000
Creator: Derenzo, Stephen E.; Klintenberg, Mattias K. & Weber, Marvin J.
Partner: UNT Libraries Government Documents Department
open access

Femtosecond electron and x-ray generation by laser andplasma-based sources

Description: The generation of ultra-short x-rays by Thomson scattering intense laser pulses from electron beams is discussed, including recent experimental results and methods for enhancing the x-ray flux. A high flux of x-rays in a femtosecond pulse requires the generation of femtosecond electron bunches and a head-on Thomson scattering geometry. The generation of ultrashort electron bunches in a plasma-based accelerator with an injection technique that uses two colliding laser pulses is discussed. Simula… more
Date: February 1, 2000
Creator: Esarey, E. & Leemans, W. P.
Partner: UNT Libraries Government Documents Department
open access

Dynamic and Thermodynamic Behavior of Carboneous and Hydrogen-Bonding Materials

Description: Dissociation behavior of carboneous materials with or without fluorine atoms at pressures (P) of tens of gigapascal (GPa) and temperature (T) at several thousand Kelvin is not so well understood. The main issues are: (a) carbon condensation processes and (b) thermodynamics of hydrogen fluoride (HF) produced from dissociation. Item (a) requires information on (i) the melting line of carbon, (ii) liquid carbon, (iii) stability and energy barrier between graphite and diamond clusters, and (iv) kin… more
Date: February 4, 2000
Creator: Ree, F. H.; Galli, G.; Glosli, J. N.; Gygi, F.; Schwegler, E.; Viecelli, J. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Effective File I/O Bandwidth Benchmark

Description: The effective I/O bandwidth benchmark (b{_}eff{_}io) covers two goals: (1) to achieve a characteristic average number for the I/O bandwidth achievable with parallel MPI-I/O applications, and (2) to get detailed information about several access patterns and buffer lengths. The benchmark examines ''first write'', ''rewrite'' and ''read'' access, strided (individual and shared pointers) and segmented collective patterns on one file per application and non-collective access to one file per process.… more
Date: February 15, 2000
Creator: Rabenseifner, R. & Koniges, A. E.
Partner: UNT Libraries Government Documents Department
open access

The Advantages of Fixed Facilities in Characterizing TRU Wastes

Description: In May 1998 the Hanford Site started developing a program for characterization of transuranic (TRU) waste for shipment to the Waste Isolation Pilot Plant (WIPP) in New Mexico. After less than two years, Hanford will have a program certified by the Carlsbad Area Office (CAO). By picking a simple waste stream, taking advantage of lessons learned at the other sites, as well as communicating effectively with the CAO, Hanford was able to achieve certification in record time. This effort was further … more
Date: February 8, 2000
Creator: FRENCH, M.S.
Partner: UNT Libraries Government Documents Department
open access

Ammonia Solubility in High Concentration Salt Solutions

Description: Solubility data for ammonia in water and various dilute solutions are abundant in the literature. However, there is a noticeable lack of ammonia solubility data for high salt, basic solutions of various mixtures of salts including those found in many of the Hanford Washington underground waste tanks. As a result, models based on solubility data for dilute salt solutions have been used to extrapolate to high salt solutions. These significant extrapolations need to be checked against actual labor… more
Date: February 1, 2000
Creator: HEDENGREN, D.C.
Partner: UNT Libraries Government Documents Department
open access

Development of the DOE Nuclear Criticality Safety Program Web Site for the Nuclear Criticality Safety Professional

Description: Development of the DOE Nuclear Criticality Safety Program (NCSP) web site is the result of the efforts of marry members of the Nuclear Criticality Safety (NCS) community and is maintained by Lawrence Livermore National Laboratory under the direction of the NCSP Management Team. This World Wide Web (WWW) resource was developed as part of the DOE response to the DNFSB Recommendation 97-2, which reflected the need to make criticality safety information available to a wide audience. The NCSP web si… more
Date: February 1, 2000
Creator: Lee, C. K.; Huang, S.; Morman, J. A. & Garcia, A. S.
Partner: UNT Libraries Government Documents Department
open access

Wavelets on Planar Tesselations

Description: We present a new technique for progressive approximation and compression of polygonal objects in images. Our technique uses local parameterizations defined by meshes of convex polygons in the plane. We generalize a tensor product wavelet transform to polygonal domains to perform multiresolution analysis and compression of image regions. The advantage of our technique over conventional wavelet methods is that the domain is an arbitrary tessellation rather than, for example, a uniform rectilinear… more
Date: February 25, 2000
Creator: Bertram, M.; Duchaineau, M.A.; Hamann, B. & Joy, K.I.
Partner: UNT Libraries Government Documents Department
open access

Bioinformatics in the information age

Description: There is a well-known story about the blind man examining the elephant: the part of the elephant examined determines his perception of the whole beast. Perhaps bioinformatics--the shotgun marriage between biology and mathematics, computer science, and engineering--is like an elephant that occupies a large chair in the scientific living room. Given the demand for and shortage of researchers with the computer skills to handle large volumes of biological data, where exactly does the bioinformatics… more
Date: February 1, 2000
Creator: Spengler, Sylvia J.
Partner: UNT Libraries Government Documents Department
open access

Effects of Confinement on Combustion of TNT Explosion Products in Air

Description: Turbulent combustion fields established by detonative explosions of TNT in confinements of different sizes are studied by high-resolution numerical simulation, using AMR (Adaptive Mesh Refinement) method. The chambers are filled with nitrogen or air at NPT conditions. In the second case, the detonation products, rich in C and CO, act, upon turbulent mixing with air, as fuel in an exothermic process of combustion, manifested by a distinct pressure rise. It is the evolution in space and time of t… more
Date: February 5, 2000
Creator: Kuhl, A.L.; Oppenheim, A.K.; Ferguson, R.E.; Reichenback, H. & Neuwald, P.
Partner: UNT Libraries Government Documents Department
open access

3-D Numerical Modeling of a Complex Salt Structure

Description: Reliably processing, imaging, and interpreting seismic data from areas with complicated structures, such as sub-salt, requires a thorough understanding of elastic as well as acoustic wave propagation. Elastic numerical modeling is an essential tool to develop that understanding. While 2-D elastic modeling is in common use, 3-D elastic modeling has been too computationally intensive to be used routinely. Recent advances in computing hardware, including commodity-based hardware, have substantiall… more
Date: February 17, 2000
Creator: House, L.; Larsen, S. & Bednar, J. B.
Partner: UNT Libraries Government Documents Department
open access

National energy use of consumer electronics in 1999

Description: The major consumer electronics in U.S. homes accounted for nearly 7 percent of U.S. residential electricity consumption in 1999. We attribute more than half of this figure (3.6 percent) to televisions, videocassette recorders, and DVD players, and nearly one-third (1.8 percent) to audio products. Set-top boxes currently account for a relatively small fraction of residential electricity use (0.7 percent), but we expect this end-use to grow quickly with the proliferation of digital set-top boxes,… more
Date: February 15, 2000
Creator: Rosen, Karen; Meier, Alan & Zandelin, Stefan
Partner: UNT Libraries Government Documents Department
open access

Part 1: Participatory Ergonomics Approach to Waste Container Handling Utilizing a Multidisciplinary Team

Description: This multidisciplinary team approach to waste container handling, developed within the Grassroots Ergonomics process, presents participatory ergonomic interpretations of quantitative and qualitative aspects of this process resulting in a peer developed training. The lower back, shoulders, and wrists were identified as frequently injured areas, so these working postures were a primary focus for the creation of the workers' training. Handling procedures were analyzed by the team to identify commo… more
Date: February 7, 2000
Creator: Zalk, D.M.; Tittiranonda, P.; Burastero, S.; Biggs, T.W.; Perry, C.M.; Tageson, R. et al.
Partner: UNT Libraries Government Documents Department
open access

EUV Engineering Test Stand

Description: The Engineering Test Stand (ETS) is an EUV laboratory lithography tool. The purpose of the ETS is to demonstrate EUV full-field imaging and provide data required to support production-tool development. The ETS is configured to separate the imaging system and stages from the illumination system. Environmental conditions can be controlled independently in the two modules to maximize EUV throughput and environmental control. A source of 13.4 nm radiation is provided by a laser plasma source in whi… more
Date: February 14, 2000
Creator: Tichenor, D. A.; Kubiak, G. D.; Replogle, W. C.; Klebanoff, L. E.; Wronosky, J. B.; Hale, L. C. et al.
Partner: UNT Libraries Government Documents Department
open access

Preparing for Implementation of DOE O 435.1 at Hanford

Description: Implementation of a new DOE Order at a complex site like Hanford is not as simple as just stating that the Order is to be followed. There are contractual changes, interface adjustments and institutional obstacles to overcome that all must be properly analyzed and dealt with before the actual physical changes embodied in the new requirements can be put into practice. In planning for these changes associated with the new DOE 0 435.1 ''Radioactive Waste Management'', the Richland Operations Office… more
Date: February 1, 2000
Creator: FRITZ, D.W.
Partner: UNT Libraries Government Documents Department
open access

New Direction in Hydrogeochemical Transport Modeling: Incorporating Multiple Kinetic and Equilibrium Reaction Pathways

Description: At least two distinct kinds of hydrogeochemical models have evolved historically for use in analyzing contaminant transport, but each has important limitations. One kind, focusing on organic contaminants, treats biodegradation reactions as parts of relatively simple kinetic reaction networks with no or limited coupling to aqueous and surface complexation and mineral dissolution/precipitation reactions. A second kind, evolving out of the speciation and reaction path codes, is capable of handling… more
Date: February 2, 2000
Creator: Steefel, C.I.
Partner: UNT Libraries Government Documents Department
open access

Mining Surveillance and Maintenance Dollars

Description: Accelerating site cleanup to reduce facility risks to the workers, the public and the environment during a time of declining federal budgets represents a significant technical and economic challenge to U.S. Department of Energy (DOE) Operations Offices and their respective contractors. A significant portion of a facility's recurring annual expenses are associated with routine, long-term surveillance and maintenance (S&M) activities. However, ongoing S&M activities do nothing to reduce r… more
Date: February 1, 2000
Creator: MARTINEZ, R.
Partner: UNT Libraries Government Documents Department
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