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open access

Analyzing occupancy profiles from a lighting controls field study

Description: Despite a number of published studies on the effectiveness of lighting controls in buildings, only one US study examines the occupancy patterns of building occupants. Occupancy profiles allow one to determine, for example, the probability that an office is occupied for each hour of the workday. Occupancy profiles are useful for many purposes including: (1) predicting the effectiveness of occupancy sensors for reducing peak demand, (2) evaluating the impact of human activity on building lighting… more
Date: April 30, 2003
Creator: Rubinstein, Francis; Colak, Nesrin; Jennings, Judith & Neils, Danielle
Partner: UNT Libraries Government Documents Department
open access

Assessing I-Grid(TM) web-based monitoring for power quality and reliability benchmarking

Description: This paper presents preliminary findings from DOEs pilot program. The results show how a web-based monitoring system can form the basis for aggregation of data and correlation and benchmarking across broad geographical lines. A longer report describes additional findings from the pilot, including impacts of power quality and reliability on customers operations [Divan, Brumsickle, Eto 2003].
Date: April 30, 2003
Creator: Divan, Deepak; Brumsickle, William & Eto, Joseph
Partner: UNT Libraries Government Documents Department
open access

Electron microscopy of biological macromolecules: Bridging the gapbetween what physics allows and what we currently can get

Description: The resolution achieved in low-dose electron microscopy of biological macromolecules is significantly worse than what can be obtained on the same microscopes with more robust specimens. When two-dimensional crystals are used, it is also apparent that the high-resolution image contrast is much less than what it could be if the images were perfect. Since specimen charging is one factor that might limit the contrast and resolution achieved with biological specimens, we have investigated the use of… more
Date: April 30, 2003
Creator: Typke, Dieter; Downing, Kenneth H. & Glaeser, Robert M.
Partner: UNT Libraries Government Documents Department
open access

Mullite/Mo interfaces formed by Intrusion bonding

Description: The microstructure and strength of Mo/mullite interfaces formed by diffusion bonding at 1650 C has been analyzed. Interfacial metal-ceramic interlocking contributes to flexural strength of approx. 140 MPa as measured by 3 point bending. Saturation of mullite with MoO2 does not affect the interfacial strength.
Date: April 30, 2003
Creator: Bartolome, Jose F.; Diaz, Marcos; Moya, Jose S.; Saiz, Eduardo & Tomsia, Antoni P.
Partner: UNT Libraries Government Documents Department
open access

Prospects for higgs search at D0

Description: The D0 experiment is recording physics quality data. Both the detector and the accelerator performance are continually improving. We are studying issues such as the b{bar b} mass resolution, b-jet tagging efficiency, missing E{sub T} resolution, and backgrounds to Higgs processes. We look forward to seeing exciting results. The status of the Higgs search at the upgraded D0 detector is discussed.
Date: April 30, 2003
Creator: Snyder, Scott S.
Partner: UNT Libraries Government Documents Department
open access

Transport in a Microfluidic Catalytic Reactor

Description: A study of the heat and mass transfer, flow, and thermodynamics of the reacting flow in a catalytic microreactor is presented. Methanol reforming is utilized in the fuel processing system driving a micro-scale proton exchange membrane fuel cell. Understanding the flow and thermal transport phenomena as well as the reaction mechanisms is essential for improving the efficiency of the reforming process as well as the quality of the processed fuel. Numerical studies have been carried out to charact… more
Date: April 30, 2003
Creator: Park, Hyun Gyu; Chung, Jaewon; Grigoropoulos, Costas P.; Greif, Ralph; Havstad, Mark & Morse, Jeffrey D.
Partner: UNT Libraries Government Documents Department
open access

Imaging of CO{sub 2} injection during an enhanced-oil-recovery experiment

Description: A series of time-lapse seismic cross well and single well experiments were conducted in a diatomite reservoir to monitor the injection of CO{sub 2} into a hydrofracture zone, using P- and S-wave data. During the first phase the set of seismic experiments were conducted after the injection of water into the hydrofrac-zone. The set of seismic experiments was repeated after a time period of 7 months during which CO{sub 2} was injected into the hydrofractured zone. The issues to be addressed ranged… more
Date: April 29, 2003
Creator: Gritto, Roland; Daley, Thomas M. & Myer, Larry R.
Partner: UNT Libraries Government Documents Department
open access

Modeling studies of mountain-scale radionuclide transport in the unsaturated zone at Yucca Mountain, Nevada

Description: We investigate radionuclide transport from a high-level nuclear waste repository to be situated in the unsaturated zone (UZ) at Yucca Mountain (YM), Nevada. Several radioactive solutes (that cover the range of sorption behavior) and colloids of various sizes are studied. The results of the study indicate the importance of the subsurface geology and site hydrology, i.e., the presence of faults (they dominate and control transport), fractures (the main migration pathways), and the relative distri… more
Date: April 29, 2003
Creator: Moridis, George J.; Seol, Yongkoo & Wu, Yu-Shu
Partner: UNT Libraries Government Documents Department
open access

Particle aggregation with simultaneous surface growth

Description: Particle aggregation with simultaneous surface growth was modeled using a dynamic Monte Carlo method. The Monte Carlo algorithm begins in the particle inception zone and constructs aggregates via ensemble-averaged collisions between spheres and deposition of gaseous species on the sphere surfaces. Simulations were conducted using four scenarios. The first, referred to as scenario 0, is used as a benchmark and simulates aggregation in the absence of surface growth. Scenario 1 forces all balls to… more
Date: April 29, 2003
Creator: Mitchell, Pablo & Frenklach, Michael
Partner: UNT Libraries Government Documents Department
open access

Repackaging of Two Bulged Crimp Sealed Cans Containing Plutonium Bearing Materials

Description: Two cans containing plutonium bearing materials were found during radiography surveillance activities to be bulged. The cans had been stored in DOT 6M shipping containers at the Savannah River Site. The material in the first can (Item CZA96-179) was packaged can/bag/can configuration with the inner and outer cans being crimp sealed. The crimp sealed innermost can was clearly deformed from the radiography picture taken for surveillance purposes. This material had been stored in the shipping cont… more
Date: April 29, 2003
Creator: Watkins, R. W.
Partner: UNT Libraries Government Documents Department
open access

Strategies for gas production from hydrate accumulations under various geologic conditions

Description: In this paper we classify hydrate deposits in three classes according to their geologic and reservoir conditions, and discuss the corresponding production strategies. Simple depressurization appears promising in Class 1 hydrates, but its appeal decreases in Class 2 and Class 3 hydrates. The most promising production strategy in Class 2 hydrates involves combinations of depressurization and thermal stimulation, and is clearly enhanced by multi-well production-injection systems. The effectiveness… more
Date: April 29, 2003
Creator: Moridis, G. & Collett, T.
Partner: UNT Libraries Government Documents Department
open access

Verification & Validation: Goals, Methods, Levels, and Metrics

Description: This work briefly summarizes the current status of the V and V Program at LLNL regarding goals, methods, timelines, and issues for Verification and Validation (V and V) with Uncertainty Quantification (UQ). The goals are to evaluate various V and V methods, to apply them to computational simulation analyses, and integrate them into methods for Quantitative Certification techniques for the nuclear stockpile. Methods include qualitative and quantitative V and V processes with numerical values for… more
Date: April 29, 2003
Creator: Logan, R W & Nitta, C K
Partner: UNT Libraries Government Documents Department
open access

Simulation of water-rock interaction in the yellowstone geothermal system using TOUGHREACT

Description: The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to accurately simulate water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a seri… more
Date: April 28, 2003
Creator: Dobson, P. F.; Salah, S.; Spycher, N. & Sonnenthal, E.
Partner: UNT Libraries Government Documents Department
open access

Simulation of water-rock interaction in the Yellowstone geothermal system using TOUGHREACT

Description: The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to simulate the chemical and hydrological effects of water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin… more
Date: April 28, 2003
Creator: Dobson, Patrick F.; Salah, Sonia; Spycher, Nicolas & Sonnenthal, Eric L.
Partner: UNT Libraries Government Documents Department
open access

Electrochemical Hydrogen Sensor for Safety Monitoring

Description: A hydrogen safety sensor is presented which provides high sensitivity and fast response time when operated in air. The target application for the sensor is external deployment near systems using or producing high concentrations of hydrogen. The sensor is composed of a catalytically active metal-oxide sensing electrode and a noble metal reference electrode attached to an yttria-stabilized zirconia (YSZ) electrolyte. The sensing approach is based on the difference in oxidation rate of hydrogen on… more
Date: April 25, 2003
Creator: Martin, L. P.; Pham, A. Q. & Glass, R. S.
Partner: UNT Libraries Government Documents Department
open access

Innovative Flash Control in Inertia Welding

Description: Inertia welding is widely used to join cylindrically shaped objects such as disks and shafts in turbine engines, turbochargers, etc. Flash control in many of these applications is not critical because the excess material is on external surfaces and can readily be removed by machining. Internal flash on hollow vessels, however, may be difficult or impossible to remove and may be either controlled by the use of flash traps or the part can be used as welded. Both internal flash and flash traps red… more
Date: April 25, 2003
Creator: Korinko, P.S.
Partner: UNT Libraries Government Documents Department
open access

Non-darcy flow behavior mean high-flux injection wells in porous and fractured formations

Description: This paper presents a study of non-Darcy fluid flow through porous and fractured rock, which may occur near wells during high-flux injection of waste fluids into underground formations. Both numerical and analytical models are used in this study. General non-Darcy flow is described using the Forchheimer equation, implemented in a three-dimensional, multiphase flow reservoir simulator. The non-Darcy flow through a fractured reservoir is handled using a general dual continuum approach, covering c… more
Date: April 25, 2003
Creator: Wu, Yu-Shu
Partner: UNT Libraries Government Documents Department
open access

Phylo-VISTA: An interactive visualization tool for multiple DNAsequence alignments

Description: Motivation. The power of multi-sequence comparison forbiological discovery is well established and sequence data from a growinglist of organisms is becoming available. Thus, a need exists forcomputational strategies to visually compare multiple aligned sequencesto support conservation analysis across various species. To be efficientthese visualization algorithms require the ability to universally handlea wide range of evolutionary distances while taking into accountphylogeny Results. We have de… more
Date: April 25, 2003
Creator: Shah, Nameeta; Couronne, Olivier; Pennacchio, Len A.; Brudno, Michael; Batzoglou, Serafim; Bethel, E. Wes et al.
Partner: UNT Libraries Government Documents Department
open access

Variability in energy factor test results for residential electric water heaters

Description: Recent modifications to the minimum energy efficiency requirements for residential water heaters have spurred an investigation into the variability in testing high-efficiency electric water heaters. While initial inter-laboratory comparisons showed excellent agreement between test results from different labs, subsequent inter-laboratory comparisons show differences between measured energy factors of up to 0.040. To determine the source of these differences, analyses of various parts of the test… more
Date: April 25, 2003
Creator: Healy, William; Lutz, James D. & Lekov, Alex
Partner: UNT Libraries Government Documents Department
open access

Concepts for Smart Protective High-Temperature Coatings

Description: The need for environmental resistance is a critical material barrier to the operation of fossil systems with the improved energy efficiencies and emissions performance described by the goals of the Vision 21 concept of the U.S. Department of Energy's Office of Fossil Energy. All fossil fuel-derived processes contain reactive species and high-temperature degradation arising from reactions of solids with gases and condensible products often limits performance or materials lifetimes such that effi… more
Date: April 24, 2003
Creator: Tortorelli, P. F.; Brady, M. P. & Wright, I. G.
Partner: UNT Libraries Government Documents Department
open access

Drip Irrigation Aided Phytoremediation for Removal of TCE from Groundwater

Description: Groundwater in D-Area at the Savannah River Site (SRS) is contaminated with trichloroethylene (TCE) and by-products resulting from discharges of this organic solvent during past disposal practices. This contaminated groundwater occurs primarily at depths of 9 meters to 15 meters below ground surface, well below the depths that are typically penetrated by plant roots. The process investigated in this study involved pumping water from the contaminated aquifer and discharging the water into overly… more
Date: April 24, 2003
Creator: Wilde, E.W.
Partner: UNT Libraries Government Documents Department
open access

Effects of Wet Air and Synthetic Combustion Gas Atmospheres on the Oxidation Behavior of Mo-Si-B Alloys

Description: Continuing our work on understanding the oxidation behavior of multiphase composite alloys based on the Mo-Si-B system, we investigated three alloys in the Mo-Si-B system, designated as A1, A2, and A3. The nominal phase assemblages of these alloys are: A1 = Mo{sub 5}Si{sub 3}B{sub x} (T1)-MoSi{sub 2}-MoB, A2 = T1-Mo{sub 5}SiB{sub 2} (T2)-Mo{sub 3}Si, and A3 = Mo-T2-Mo{sub 3}Si. Our previous work showed that for exposures to 1100 C, all alloys formed a protective oxide scale in dry air. Exposure… more
Date: April 24, 2003
Creator: Kramer, M. J.; Thom, A. J.; Mandal, P.; Behrani, V. & Akinc, M.
Partner: UNT Libraries Government Documents Department
open access

Electron-beam diagnostic for space-charge measurement of an ion beam

Description: An electron beam diagnostic system for measuring the charge distribution of an ion beam without changing its properties is presently under development for Heavy Ion Fusion (HIF) beam physics studies. Conventional diagnostics require temporary insertion of sensors into the beam, but these capture it, or significantly alter its properties. In this new diagnostic a low energy, low current electron beam is scanned transversely across the ion beam; the measured electron beam deflection is used to ca… more
Date: April 24, 2003
Creator: Roy, Prabir K.; Yu, Simon S.; Henestroza, Enrique; Eylon, Shmuel; Shuman, Derek B.; Ludvig, Jozsef et al.
Partner: UNT Libraries Government Documents Department
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