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Active, Non-Intrusive Inspection Technologies for Homeland Defense (open access)

Active, Non-Intrusive Inspection Technologies for Homeland Defense

Active, non-intrusive inspection or interrogation technologies have been used for 100 years - with the primary focus being radiographic imaging. During the last 50 years, various active interrogation systems have been investigated and most have revealed many unique and interesting capabilities and advantages that have already benefited the general public. Unfortunately, except for medical and specific industrial applications, these unique capabilities have not been widely adopted, largely due to the complexity of the technology, the overconfident reliance on passive detection systems to handle most challenges, and the unrealistic public concerns regarding radiation safety issues for a given active inspection deployment. The unique homeland security challenges facing the United States today are inviting more "out-of-the-box" solutions and are demanding the effective technological solutions that only active interrogation systems can provide. While revolutionary new solutions are always desired, these technology advancements are rare, and when found, usually take a long time to fully understand and implement for a given application. What's becoming more evident is that focusing on under-developed, but well-understood, active inspection technologies can provide many of the needed "out-of-the-box" solutions. This paper presents a brief historical overview of active interrogation. It identifies some of the major homeland defense challenges being …
Date: June 1, 2003
Creator: Jones, James L.
System: The UNT Digital Library
Automated Batch Characterization of Icf Shells With Vision-Enabled Optical Microscope System (open access)

Automated Batch Characterization of Icf Shells With Vision-Enabled Optical Microscope System

OAK-B135 Inertial Confinement Fusion (ICF) shells are mesoscale objects with nano-scale dimensional and nano-surface finish requirements. Currently, the shell dimensions are measured by white-light interferometry and an image analysis method. These two methods complement each other and give a rather complete data set on a single shell. The process is, however, labor intensive. They have developed an automation routine to fully characterize a shell in one shot and perform unattended batch measurements. The method is useful to the ICF program both for production screening and for full characterization. It also has potential for Inertial Fusion Energy (IFE) power plant where half a million shells need to be processed daily.
Date: June 1, 2003
Creator: Huang, H.; Stephens, R. B.; Hill, D. W.; Lyon, C.; Nikroo, A. & Steinman, D. A.
System: The UNT Digital Library
Civilian Power from Space in the Early 21st Century (open access)

Civilian Power from Space in the Early 21st Century

If power beamed from space is to be become widely used on Earth in the first half of the 21St century, several thus-far-persistent impediments must be obviated, including threshold effects and problematic aspects of cost, availability, reliability, hazards and environmental impacts. We sketch a generally-applicable route to doing so, noting key enabling technologies and practical features. Likely-essential features of any successful strategy include vigorous, systematic leveraging of all intrinsic features of space-derived power, e.g., addressing marginal, high-value-added markets for electric power in space- and time-agile manners to conveniently provide power-upon-demand, and incrementally ''wedging'' into ever-larger markets with ever more cost-efficient generations and scales of technology. We suggest that no prudent strategic plan will rely upon large-scale, long-term public subsidies--fiscal, regulatory, etc.--with their attendant ''sovereign risks'' and interminable delays, and that plan-essential governmental support likely will be limited to early feasibility demonstrations, provision of threshold technologies and a rational, competition-neutral licensing environment. If salient realities are uniformly respected and accessible technologies are intelligently leveraged, electricity derived from space-sourced power-beams may come into significant civilian use during the latter part of the first quarter of this century, and may become widely used by the half-century point.
Date: June 1, 2003
Creator: Hyde, R.; Ishikawa, M. & Wood, L.
System: The UNT Digital Library
Complete Suppression of the M/N=2/1 Neoclassical Tearing Mode Using Radially Localized Electron Cyclotron Current Drive on Diii-D and the Requirements for Iter (open access)

Complete Suppression of the M/N=2/1 Neoclassical Tearing Mode Using Radially Localized Electron Cyclotron Current Drive on Diii-D and the Requirements for Iter

OAK-B135 DIII-D experiments demonstrate the first real-time feedback control of the relative location of a narrow beam of microwaves to completely suppress and eliminate a growing tearing mode at the q=2 surface. long wavelength tearing modes such as the m/n = 2/1 instability are particularly deleterious to tokamak operation. Confinement is seriously degraded by the island, plasma rotation can cease (mode-lock) and disruption can occur. The neoclassical tearing mode (NTM) becomes unstable due to the presence of a helically-perturbed bootstrap current and can be stabilized by replacing the missing bootstrap current in the island O-point by precisely located co-electron cyclotron current drive (ECCD). The geometry for the ECCD launch, the second harmonic resonance 2f{sub ce} and the q=2 surface are shown. The optimum position is found when the DIII-D plasma control system (PCS) is put into a search and suppress mode that makes small radial shifts (in about 1 cm steps) in the ECCD location based on minimizing the Mirnov amplitude.
Date: June 1, 2003
Creator: La Haye, R. J.; Luce, T. C.; Petty, C. C.; Humphreys, D. A.; Hyatt, A. W.; Perkins, F. W. et al.
System: The UNT Digital Library
Complete Surface Mapping of Icf Shells (open access)

Complete Surface Mapping of Icf Shells

OAK-B135 Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. they have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r({theta},{psi}) surface map for accurate 3-D modeling of a shot.
Date: June 1, 2003
Creator: Stephens, R. B.; Olson, D.; Huang, H. & Gibson, J. B
System: The UNT Digital Library
A conceptual model to estimate cost effectiveness of the indoor environment improvements (open access)

A conceptual model to estimate cost effectiveness of the indoor environment improvements

Macroeconomic analyses indicate a high cost to society of a deteriorated indoor climate. The few example calculations performed to date indicate that measures taken to improve IEQ are highly cost-effective when health and productivity benefits are considered. We believe that cost-benefit analyses of building designs and operations should routinely incorporate health and productivity impacts. As an initial step, we developed a conceptual model that shows the links between improvements in IEQ and the financial gains from reductions in medical care and sick leave, improved work performance, lower employee turn over, and reduced maintenance due to fewer complaints.
Date: June 1, 2003
Creator: Seppanen, Olli & Fisk, William J.
System: The UNT Digital Library
CONTROL OF MHD STABILITY IN DIII-D ADVANCED TOKAMAK DISCHARGES (open access)

CONTROL OF MHD STABILITY IN DIII-D ADVANCED TOKAMAK DISCHARGES

OAK-B135 Advanced tokamak research in DIII-D seeks to optimize the tokamak approach for fusion energy production, leading to a compact, steady state power source. High power density implies operation at high toroidal beta, {beta}{sub T}=<p>2{micro}{sub 0}/B{sub T}{sup 2}, since fusion power density increases roughly as the square of the plasma pressure. Steady-state operation with low recirculating power for current drive implies operation at high poloidal beta, {beta}{sub P} = <p>2{micro}{sub 0}/<B{sub P}>{sup 2}, in order to maximize the fraction of self-generated bootstrap current. Together, these lead to a requirement of operation at high normalized beta, {beta}{sub N} = {beta}{sub T}(aB/I), since {beta}{sub P}{beta}{sub T} {approx} 25[(1+{kappa}{sup 2})/2] ({beta}{sub N}/100){sup 2}. Plasmas with high normalized beta are likely to operate near one or more stability limits, so control of MHD stability in such plasmas is crucial.
Date: June 1, 2003
Creator: Strait, E. J.; Bialek, J.; Chance, M. S.; Chu, M. S.; Edgell, D. H.; Ferron, J. R. et al.
System: The UNT Digital Library
Correlation of Structural and Electronic Properties with Solar Cell Efficiency for Amorphous Silicon Deposited at Increasing Growth Rates (open access)

Correlation of Structural and Electronic Properties with Solar Cell Efficiency for Amorphous Silicon Deposited at Increasing Growth Rates

This paper details the effects of increasing the growth rate of hydrogenated amorphous silicon (a-Si:H), deposited by dc plasma chemical vapor deposition, on the structural and electronic properties of the material in comparison with the performance of solar cells incorporating such layers. The hydrogen content exhibits the strongest correlation with the solar cell efficiency. The defect density measured by two different techniques, correlate poorly but when measured by a third technique, correlates well. On the other hand, the Urbach tail slope correlated well when measured by two different techniques but poorly when measured by a third one.
Date: June 1, 2003
Creator: Ganguly, G.; Han, D.; Williamson, D. L.; Nelson, B. P. & Cohen, J. D.
System: The UNT Digital Library
Cost benefit analysis of the night-time ventilative cooling in office building (open access)

Cost benefit analysis of the night-time ventilative cooling in office building

The indoor temperature can be controlled with different levels of accuracy depending on the building and its HVAC system. The purpose of this study was to evaluate the potential productivity benefits of improved temperature control, and to apply the information for a cost-benefit analyses of night-time ventilative cooling, which is a very energy efficient method of reducing indoor daytime temperatures. We analyzed the literature relating work performance with temperature, and found a general decrement in work performance when temperatures exceeded those associated with thermal neutrality. These studies included physiological modelling, performance of various tasks in laboratory experiments and measured productivity at work in real buildings. The studies indicate an average 2% decrement in work performance per degree C temperature rise, when the temperature is above 25 C. When we use this relationship to evaluate night-time ventilative cooling, the resulting benefit to cost ratio varies from 32 to 120.
Date: June 1, 2003
Creator: Seppanen, Olli; Fisk, William J. & Faulkner, David
System: The UNT Digital Library
Creating a Public Web Database about High Performance (Green) Buildings: Preprint (open access)

Creating a Public Web Database about High Performance (Green) Buildings: Preprint

Preprint of conference paper about the DOEs High Performance Buildings Database to be presented at the ASHRAE Conference in Scotland in September 2003.
Date: June 1, 2003
Creator: Crawley, D. B.; Torcellini, P. & Malin, N.
System: The UNT Digital Library
Decision-making through performance simulation and code compliance from the early, schematic phases of building design (open access)

Decision-making through performance simulation and code compliance from the early, schematic phases of building design

None
Date: June 1, 2003
Creator: Reichard, Georg & Papamichael, Konstantinos
System: The UNT Digital Library
Designing for smoking rooms (open access)

Designing for smoking rooms

None
Date: June 1, 2003
Creator: Alevantis, L.; Wagner, J.; Fisk, B.; Sullivan, D.; Faulkner, D.; Gundel, L. et al.
System: The UNT Digital Library
Development of a Dynamic Spot Size Diagnostic for Flash Radiographic X-Ray Sources (open access)

Development of a Dynamic Spot Size Diagnostic for Flash Radiographic X-Ray Sources

There has been considerable work in recent years in the development of high-brightness, high-dose flash x-ray radiographic sources. Spot size is one of several parameters that helps characterize source performance and provides a figure of merit to assess the suitability of various sources to specific experimental requirements. Time-integrated spot-size measurements using radiographic film and a high-Z rolled-edge object have been used for several years with great success. The Advanced Radiographic Technologies program thrust to improve diode performance requires extending both modeling and experimental measurements into the transient time domain. A new Time Resolved Spot Detector (TRSD) is under development to provide this information. In this paper we report the initial results of the performance of a 148-element scintillating fiber array that is fiber-optically coupled to a gated streak camera. Spatial and temporal resolution results are discussed and the data obtained from the Sand ia National Laboratories (SNL) RITS-3 (Radiographic Integrated Test Stand) accelerator are presented.
Date: June 1, 2003
Creator: Droemer, D. W.; Lutz, S.; Devore, D.; Rovang, D.; Portillo, S. & Maenchen, J.
System: The UNT Digital Library
Diffusion of alkali species in porous tungsten substrates used in contact-ionization sources (open access)

Diffusion of alkali species in porous tungsten substrates used in contact-ionization sources

Contact ionization (doped) sources used in current Heavy Ion Fusion (HIF) experiments consist of a porous tungsten substrate doped with an alkali carbonate. During the early stages of the heating cycle (T {approx} 600 C), the carbonate breaks down and releases the alkali atoms that then diffuse through the substrate. At the emitter surface there is a balance between the fast desorption rate of the alkali atoms (mostly as neutrals) and the slower replenishment rate from the substrate by diffusion. Time-resolved measurements of neutral particle evaporation rates at the emitter surface have been used to estimate the effective diffusion coefficient (D) that characterizes the migration of alkali species in the substrate. These estimates are consistent with the observed source lifetimes (tens of hrs.) and establish the alkali migration in the bulk as a diffusion-limited process. The measurements suggest that the faster migration rates (D {approx} 10{sup -5}-10{sup -6} cm{sup 2}/s) occur early during the heating cycle when the dominant species are the neutral alkali atoms. At operating temperatures there is a slower migration rate (D {approx} 10{sup -7} cm{sup 2}/s) due to the dominance of ions, which diffuse by a slower surface diffusion process.
Date: June 1, 2003
Creator: Chacon-Golcher, E.; Kwan, J. W. & Morse, E. C.
System: The UNT Digital Library
DLTS Characterization of CIGS Cells (open access)

DLTS Characterization of CIGS Cells

Deep Level Transient Spectroscopy (DLTS) and Capacitance-Voltage (C-V) measurements are employed to study deep-level electron and hole traps in CIGS solar cells fabricated at two different locations (EPV and NREL). The activation energy and trap density as well as suggested defect origins are given.
Date: June 1, 2003
Creator: Kerr, L. L.; Li, S. S.; Anderson, T. J.; Crisalle, O. D.; Johnston, S.; Abushama, J. et al.
System: The UNT Digital Library
Economizer system cost effectiveness: Accounting for the influence of ventilation rate on sick leave (open access)

Economizer system cost effectiveness: Accounting for the influence of ventilation rate on sick leave

This study estimated the health, energy, and economic benefits of an economizer ventilation control system that increases outside air supply during mild weather to save energy. A model of the influence of ventilation rate on airborne transmission of respiratory illnesses was used to extend the limited data relating ventilation rate with illness and sick leave. An energy simulation model calculated ventilation rates and energy use versus time for an office building in Washington, DC with fixed minimum outdoor air supply rates, with and without an economizer. Sick leave rates were estimated with the disease transmission model. In the modeled 72-person office building, our analyses indicate that the economizer reduces energy costs by approximately $2000 and, in addition, reduces sick leave. The financial benefit of the decrease in sick leave is estimated to be between $6,000 and $16,000. This modelling suggests that economizers are much more cost effective than currently recognized.
Date: June 1, 2003
Creator: Fisk, William J.; Seppanen, Olli; Faulkner, David & Huang, Joe
System: The UNT Digital Library
Energy efficiency indicators for high electric-load buildings (open access)

Energy efficiency indicators for high electric-load buildings

Energy per unit of floor area is not an adequate indicator for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed.
Date: June 1, 2003
Creator: Aebischer, Bernard; Balmer, Markus A.; Kinney, Satkartar; Le Strat, Pascale; Shibata, Yoshiaki & Varone, Frederic
System: The UNT Digital Library
Fabrication and Characterization of Fast Ignition Targets (open access)

Fabrication and Characterization of Fast Ignition Targets

OAK-B135 Fast ignition is a novel scheme for achieving laser fusion. A class of these targets involves cone mounted CH shells. The authors have been fabricating such targets with shells with a wide variety of diameters and wall thicknesses for several years at General Atomics. In addition, recently such shells were needed for implosion experiments at Laboratory for Laser Energetics (LLE) that for the first time were required to be gas retentive. Fabrication of these targets requires producing appropriate cones and shells, assembling the targets, and characterization of the assembled targets. The cones are produced using micromachining and plating techniques. The shells are fabricated using the depolymerizable mandrel technique followed by micromachining a hole for the cone. The cone and the shell then need to be assembled properly for gas retention and precisely in order to position the cone tip at the desired position within the shell. Both are critical for the fast ignition experiments. The presence of the cone in the shell creates new challenges in characterization of the assembled targets. Finally, for targets requiring a gas fill, the cone-shell assembly needs to be tested for gas retention and proper strength at the glue joint. This paper presents an …
Date: June 1, 2003
Creator: Hill, D. W.; Castillo, E.; Chen, K. C.; Grant, S. E.; Greenwood, A. L.; Kaae, J. L. et al.
System: The UNT Digital Library
FABRICATION AND PROPERTIES OF OER COATED RESORCINOL-FORMALDEHYDE SHELLS FOR OMEGA EXPERIMENTS (open access)

FABRICATION AND PROPERTIES OF OER COATED RESORCINOL-FORMALDEHYDE SHELLS FOR OMEGA EXPERIMENTS

OAK-B135 New high gain designs for direct drive ignition on NIF require foam shells. Scaled down versions of these designs are needed for near term experiments on the OMEGA laser facility at the Laboratory Laser Energetics (LLE). These shells need to be about 1 mm in diameter and 50-100 {micro}m wall thickness and densities of 100-250 mg/cc. In addition, a full density permeation seal needs to be deposited for retention of the fill gas at room temperature or the ice at cryogenic temperatures. They have fabricated such shells using Resorcinol-formaldehyde (R/F) as the selected foam material due to its transparency in the optical region. Extensive characterization of the wall uniformity of these shells has been performed. The foam shells have {approx} 5%-6% non-concentricities on the average. A full density permeation seal has been deposited on the R/F shells using two different techniques. In the first technique R/F shells are coated directly with plasma polymer to thicknesses of 3-4 {micro}m. In the second technique, R/F shells are coated with polyvinylphenol, using a chemical interfacial polymerization technique. Data on surface finish and gas retention for R/F shells coated by both methods are provided.
Date: June 1, 2003
Creator: Nikroo, A.; Czechowicz, D.; Paguio, R.; Greenwood, A. L. & Takagi, M.
System: The UNT Digital Library
FABRICATION OF A NEW TYPE OF DOUBLE SHELL TARGET HAVING A PVA INNER LAYER (open access)

FABRICATION OF A NEW TYPE OF DOUBLE SHELL TARGET HAVING A PVA INNER LAYER

OAK-B135 The General Atomics Target Fabrication team was tasked in FY03, under its ICF Target Support contract, to make a new type of double-shell target. its specifications called for the outer shell to have an inner lining of PVA (poly(vinyl alcohol)) that would keep the xenon gas fill from occupying the target wall. The inner shell consisted of a glass shell coated with 2000 {angstrom} of silver and filled with 9 atm of deuterium. Furthermore, the delivery deadline was less than seven weeks away. This paper describes the fielding of this double-shell target, made possible through the combined efforts of Lawrence Livermore National Laboratory and General Atomics target fabrication specialists.
Date: June 1, 2003
Creator: Steinman, D. A; Wallace, R.; Grant, S. E.; Hoppe, M. L. & Smith, J. N., Jr.
System: The UNT Digital Library
Fabrication of Gas-Filled Tungsten-Coated Glass Shells (open access)

Fabrication of Gas-Filled Tungsten-Coated Glass Shells

OAK-B135 Deuterium (D{sub 2}) filled glass shells coated with a high Z element are needed for high energy density (HED) experiments by researchers at Los Alamos National Laboratory. They report here on our initial attempt to produce such shells. Glass shells made using the drop tower technique were coated with gold, palladium or tungsten, or a mixture of two of these elements. It was found that gold and palladium coatings did not stick well to the glass and resulted in poor or delaminated films. Tungsten coatings resulted in films suitable for these targets. Bouncing of shells during coating resulted in uniform tungsten coatings, but the surface of such coatings were filled with small nodules. Proper agitation of shells using a tapping technique resulted in smooth films with minimal particulate contamination. For coating rates of {approx} 0.15 {micro}m/hr coatings with {approx} 2 nm RMS surface finish could be deposited. The surface roughness of coatings at higher rates, 0.7 {micro}m/hr, was considerably worse ({approx} 100 nm RMS). The columnar structure of the coatings allowed permeation filling of the tungsten coated glass shells with deuterium at 300 C.
Date: June 1, 2003
Creator: Nikroo, A.; Baugh, W. & Steinman, D. A.
System: The UNT Digital Library
FABRICATION OF WINDOW SADDLES FOR NIF CRYOGENIC HOHLRAUMS (open access)

FABRICATION OF WINDOW SADDLES FOR NIF CRYOGENIC HOHLRAUMS

OAK-B135 A planar diagnostic viewing port attached to the cylindrical wall of the NIF cryogenic hohlraum requires a saddle-like transition piece. While the basic design of this window saddle is straightforward, its fabrication is not, given the scale and precision of the component. They solved the problem through the use of a two segment copper mandrel to electroform the gold window saddle. The segments were micro-machined using a combination of single-point diamond turning and single point diamond milling. These processes as well as the electroplating conditions, final machining and mandrel removal are described in this paper.
Date: June 1, 2003
Creator: GIRALDEZ,E & KAAE,J.L
System: The UNT Digital Library
Frontiers of Plant Cell Biology: Signals and Pathways, System-Based Approaches 22nd Symposium in Plant Biology (University of California-Riverside) (open access)

Frontiers of Plant Cell Biology: Signals and Pathways, System-Based Approaches 22nd Symposium in Plant Biology (University of California-Riverside)

The symposium ''Frontiers of Plant Cell Biology: Signals and Pathways, Systems-Based Approaches'' was held January 15-18, 2003 at the Riverside Convention Center in Riverside, California. The host organization for the symposium was the Center for Plant Cell Biology (CEPCEB) at the University of California, Riverside (UCR). The meeting, focusing on systems-based approaches to plant cell biology research, was the first of this kind in the field of plant biology. The speakers and nearly 100 posters placed emphasis on recent developments in plant cellular biology and molecular genetics, particularly those employing emerging genomic tools, thereby sharing the most current knowledge in the field and stimulating future advances. In attendance were many well-established scientists and young investigators who approach plant cell biology from different but complementary conceptual and technical perspectives. Indeed, many disciplines are converging in the field of cell biology, producing synergies that will enable plant scientists to determine the function of gene products in the context of living cells in whole organisms. New, cross-disciplinary collaborations, as well as the involvement of computer scientists and chemists in plant biology research, are likely additional outcomes of the symposium. The program included 39 invited session speakers and workshop/panel speakers. Sessions were convened on …
Date: June 1, 2003
Creator: Minorsky, Peter V.
System: The UNT Digital Library
Gallium Safety in the Laboratory (open access)

Gallium Safety in the Laboratory

A university laboratory experiment for the US Department of Energy magnetic fusion research program required a simulant for liquid lithium. The simulant choices were narrowed to liquid gallium and galinstan (Ga-In-Sn) alloy. Safety information on liquid gallium and galinstan were compiled, and the choice was made to use galinstan. A laboratory safety walkthrough was performed in the fall of 2002 to support the galinstan experiment. The experiment has been operating successfully since early 2002.
Date: June 1, 2003
Creator: Cadwallader, Lee C.
System: The UNT Digital Library