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The dynamic information architecture system : an advanced simulation framework for military and civilian applications.

Description: DIAS, the Dynamic Information Architecture System, is an object-oriented simulation system that was designed to provide an integrating framework in which new or legacy software applications can operate in a context-driven frame of reference. DIAS provides a flexible and extensible mechanism to allow disparate, and mixed language, software applications to interoperate. DIAS captures the dynamic interplay between different processes or phenomena in the same frame of reference. Finally, DIAS accom… more
Date: January 8, 1998
Creator: Campbell, A. P. & Hummel, J. R.
Partner: UNT Libraries Government Documents Department
open access

THE CONTROLLED DRIFT DETECTOR : CHARACTERISATION OF THE READOUT MECHANISM AND OF THE CHARGE HANDLING CAPABILITY.

Description: A new position-sensing X-ray detector operated in integrate-readout mode has been recently designed and characterized. Due to the peculiar working principle of the new detector, the charge handling capability, that is the maximum charge that can be stored in a pixel, is related to the operating conditions of the device. In particular the amplitude of the barriers that confine the signal electrons during the integration phase depends on the applied drift field and on the field perturbation super… more
Date: November 8, 1998
Creator: Castoldi, A.; Gatti, E.; Guazzoni, C.; Longoni, A.; Rehak, P. & Struder, L.
Partner: UNT Libraries Government Documents Department
open access

In-vessel fluid flow measurements using thermocouples cross-correlation.

Description: Fluid flow rate in high temperature and pressure vessels can be difficult to measure due to the associated harsh environment, inaccessible locations and pressure boundary integrity concerns. However, by using quick response miniature thermocouples to measure the naturally occurring temperature variations within the flow, the fluid velocity can be inferred from the transit time analysis. This flow measurement technique has other advantages such as the flow profile is not significantly disturbed,… more
Date: May 8, 1998
Creator: NguyenLe, Q.
Partner: UNT Libraries Government Documents Department
open access

Low-temperature MOCVD growth of oriented PbZr{sub x}Ti{sub 1-x}O{sub 3} thin films on Si substrates.

Description: Polycrystalline Pb(Zr{sub 0.6}Ti{sub 0.4})O{sub 3} (PZT) thin films, 3000-6000 {angstrom} thick, have been grown by metal-organic chemical vapor deposition (MOCVD) on (111)Pt/Ti/SiO{sub 2}/Si substrates at temperatures as low as 450-525 C. Random and (111)-oriented, or occasionally (100)-oriented, PZT films can be deposited directly on (111)Pt/Ti/SiO{sub 2}/Si. In addition, highly (100)-oriented films can be deposited consistently by using 150-250 {angstrom} thick (100)-oriented PbTiO{sub 3} (P… more
Date: May 8, 1998
Creator: Chen, N.
Partner: UNT Libraries Government Documents Department
open access

THE 15 LAYER SILICON DRIFT DETECTOR TRACKER IN EXPERIMENT 896.

Description: Large linear silicon drift detectors have been developed and are in production for use in several experiments. Recently 15 detectors were used as a tracking device in BNL-AGS heavy ion experiment (E896). The detectors were successfully operated in a 6.2 T magnetic field. The behavior of the detectors, such as drift uniformity, resolution, and charge collection efficiency are presented. The effect of the environment on the detector performance is discussed. Some results from the experimental run… more
Date: November 8, 1998
Creator: Pandy, S. U.
Partner: UNT Libraries Government Documents Department
open access

Photovoltaic module performance and durability following long-term field exposure

Description: Our investigations of both new and field-aged photovoltaic modules have indicated that, in general, today's commercially available modules area highly reliable product. However, by using new test procedures, subtle failure mechanisms have also been identified that must be addressed in order to achieve 30-year module lifetimes. This paper summarizes diagnostic test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial mod… more
Date: September 8, 1998
Creator: Ellibee, D. E.; Hansen, B. R.; King, D. L.; Kratochvil, J. A. & Quintana, M. A.
Partner: UNT Libraries Government Documents Department
open access

BWR drywell behavior under steam blowdown.

Description: Historically, thermal hydraulics analyses on Large Break Loss of Coolant Accidents (LOCA) have been focused on the transients within the reactor or steam generator. Few have studied the effects of steam blowdown on the containment building. This paper discusses some theoretical issues as well as presenting numerical and experimental results of the blowdown tests performed at the Purdue University Multi-Dimensional Integrated Test Assembly (PUMA).
Date: May 8, 1998
Creator: NguyenLe, Q.
Partner: UNT Libraries Government Documents Department
open access

On-loom, real-time, noncontact detection of fabric defects by ultrasonic imaging.

Description: A noncontact, on-loom ultrasonic inspection technique was developed for real-time 100% defect inspection of fabrics. A prototype was built and tested successfully on loom. The system is compact, rugged, low cost, requires minimal maintenance, is not sensitive to fabric color and vibration, and can easily be adapted to current loom configurations. Moreover, it can detect defects in both the pick and warp directions. The system is capable of determining the size, location, and orientation of each… more
Date: September 8, 1998
Creator: Chien, H. T.
Partner: UNT Libraries Government Documents Department
open access

Relating structural parameters to leachability in a glass-bonded ceramic waste form.

Description: Lattice parameters for a crystalline material can be obtained by several methods, notably by analyzing x-ray powder diffraction patterns. By utilizing a computer program to fit a pattern, one can follow the evolution or subtle changes in a structure of a crystalline species in different environments. This work involves such a study for an essential component of the ceramic waste form that is under development at Argonne National Laboratory. Zeolite 4A and zeolite 5A are used to produce two diff… more
Date: May 8, 1998
Creator: Frank, S. M.; Johnson, S. G. & Moschetti, T. L.
Partner: UNT Libraries Government Documents Department
open access

Developing Switchgrass as a Bioenergy Crop

Description: The utilization of energy crops produced on American farms as a source of renewable fuels is a concept with great relevance to current ecological and economic issues at both national and global scales. Development of a significant national capacity to utilize perennial forage crops, such as switchgrass (Panicum virgatum, L.) as biofuels could benefit our agricultural economy by providing an important new source of income for farmers. In addition energy production from perennial cropping systems… more
Date: November 8, 1998
Creator: Bouton, J.; Bransby, D.; Conger, B.; McLaughlin, S.; Ocumpaugh, W.; Parrish, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Using Artificial Neural Networks to Assess Microbial Communities

Description: We are evaluating artificial neural networks (ANNs) as tools for assessing changes in soil microbial communities following exposure to metals. We analyzed signature lipid biomarker data collected from two soil microcosm experiments using an autoassociative ANN. In one experiment, the microcosms were exposed to O, 100, or 250 ppm of metals, and in the other experiment the microcosms were exposed to O or 500 ppm of metals. The ANNs were able to distinguish between microcosms exposed and not expos… more
Date: September 8, 1998
Creator: Almeida, J. S.; Brand, C. C.; Palumbo, A. V.; Pfiffner, S. M. & Schryver, J. C.
Partner: UNT Libraries Government Documents Department
open access

Main amplifier power conditioning for the National Ignition Facility

Description: The National Ignition Facility (NIF), being built at Lawrence Livermore National Laboratory (LLNL) will utilize a 18 MJ glass laser to study inertial confinement fusion This laser will be driven by a power conditioning system which must simultaneously deliver over 260 MJ of electrical energy to the nearly 7700 flashlamps The power conditioning system is divided into independent modules that store, shape and deliver pulses of energy to the flashlamps The NIF power conditioning system which is be… more
Date: June 8, 1998
Creator: Newton, M.
Partner: UNT Libraries Government Documents Department
open access

Microbial Population Changes During Bioremediation of an Experimental Oil Spill

Description: A field experiment was conducted in Delaware (USA) to evaluate three crude oil bioremediation techniques. Four treatments were studied: no oil control, oil alone, oil + nutrients, and oil + nutrients + an indigenous inoculum. The microbial populations were monitored by standard MPN techniques, PLFA profile analysis, and 16S rDNA DGGE analysis for species definition. Viable MPN estimates showed high but steadily declining microbial numbers and no significant differences among treatments during t… more
Date: August 8, 1998
Creator: Chang, Y. J.; Davis, G. A.; Macnaughton, S. J.; Stephen, J. R.; Venosa, A. D. & White, D. C.
Partner: UNT Libraries Government Documents Department
open access

Optical and mechanical properties of thermally evaporated fluoride thin films

Description: As a result of health and safety issues surrounding the use of radioactive materials on coated optical components, there has been renewed interest in coating materials whose optical and mechanical properties approach those offered by their radioactive counterparts. Due to the radioactive nature of ThF{sub 4} and its widespread use in optical coatings, the coating industry is examining other low index and non-radioactive fluorides as possible alternatives. In this paper, the authors present the … more
Date: June 8, 1998
Creator: Zhang, K.; Fahey, R.; Jasinski, D.; Scarpino, C.; Dziendziel, R.; Burger, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Direct qualification of digital components

Description: Existing methods for qualifying digital system software for use in safety critical systems are expensive and are based on inferences that are of doubtful validity. This report on work-in-progress describes a new approach to qualifying a class of small safety systems that can meet a number of design restrictions, where the restrictions are carefully crafted to permit safety qualification to be determined by means of static analysis of the software combined with a limited amount of testing. This … more
Date: July 8, 1998
Creator: Lawrence, J. D., LLNL
Partner: UNT Libraries Government Documents Department
open access

Influence of corannulene's curved carbon lattice (C{sub 20}H{sub 10}) on lithium intercalation.

Description: Ab initio molecular orbital calculations have been used to investigate the influence of corannulene's curved carbon lattice (C{sub 20}H{sub 10}) on lithium intercalation. This has been approximated by investigating the reaction of lithium atoms with either the corannulene molecule directly or with a sandwich structure formed from two corannulene molecules. In the first case, one corannulene molecule, three, six and seven lithiums have been used to form Li{sub 3}(C{sub 20}H{sub 10}), Li{sub 6}(C… more
Date: June 8, 1998
Creator: Scanlon, L. G.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of extractant-coated ferromagnetic microparticles for the recovery of hazardous metals from waste solution.

Description: A magnetically assisted chemical separation (MACS) process was developed earlier at Argonne National Laboratory (ANL). This compact process was designed for the separation of transuranics (TRU) and radionuclides from the liquid waste streams that exist at many DOE sites, with an overall reduction in waste volume requiring disposal. The MACS process combines the selectivity afforded by solvent extractant/ion exchange materials with magnetic separation to provide an efficient chemical separation.… more
Date: May 8, 1998
Creator: Kaminski, M. D.
Partner: UNT Libraries Government Documents Department
open access

Striped-double cavity fabry-perot interferometers using both glass and air cavities

Description: We have used piezo-driven Fabry-Perot interferometers in the past far many continuous velocity-time measurements of fast moving surfaces. In order to avoid the annoying drift of some of these devices, we have developed and used inexpensive, solid glass, striped etalons with lengths up to 64 mm. Usable apertures are 35 mm by 80 mm with a finess of 25. A roundabout technique was devised for double cavity operation. We built a passive thermal housing for temperature stability, with tilt and height… more
Date: July 8, 1998
Creator: Perry, S. & Steinmetz, L.
Partner: UNT Libraries Government Documents Department
open access

Developing enabling optics finishing technologies for the National Ignition Facility

Description: Lawrence Livermore National Laboratory is in the process of constructing the National Ignition Facility, a half million square foot facility which will house a 192 beam laser system capable of generating the 2 million joules of ultraviolet light energy necessary to achieve fusion ignition with inertial targets by 2004. More than 7,000 meter class optics will need to be manufactured by LLNL`s industrial partners to construct the laser system. The components will be manufactured starting in 1998 … more
Date: January 8, 1998
Creator: Aikens, D. M.; Rich, L.; Bajuk, D. & Slomba, A.
Partner: UNT Libraries Government Documents Department
open access

A flexible Labview{trademark}-based data acquisition and analysis system for scanning microscopy

Description: A new data analysis system has been developed with computer-controlled beam and sample positioning, video sample imaging, multiple large solid angle detectors for x-rays and gamma-rays, and surface barrier detectors for charged particles. The system uses the LabVIEW{trademark} programming language allowing it to be easily ported between different computer operating systems. In the present configuration, digital signal processors are directly interfaced to a SCSI CAMAC controller. However, the m… more
Date: October 8, 1998
Creator: Morse, Daniel H.; Antolak, Arlyn J.; Bench, Graham S. & Roberts, Mark L.
Partner: UNT Libraries Government Documents Department
open access

Argonne National Laboratory Expedited Site Characterization: First International Symposium on Integrated Technical Approaches to Site Characterization - Proceedings Volume

Description: Laboratory applications for the analysis of PCBS (polychlorinated biphenyls) in environmental matrices such as soil/sediment/sludge and oil/waste oil were evaluated for potential reduction in waste, source reduction, and alternative techniques for final determination. As a consequence, new procedures were studied for solvent substitution, miniaturization of extraction and cleanups, minimization of reagent consumption, reduction of cost per analysis, and reduction of time. These new procedures p… more
Date: June 8, 1998
Partner: UNT Libraries Government Documents Department
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