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Integrated planning: A baseline development perspective (open access)

Integrated planning: A baseline development perspective

The FEMP Baseline establishes the basis for integrating environmental activity technical requirements with their cost and schedule elements. The result is a path forward to successfully achieving the FERMCO mission. Specific to cost management, the FEMP Baseline has been incorporate into the FERMCO Project Control System (PCS) to provide a time-phased budget plan against which contractor performance is measured with an earned value management system. The result is the Performance Measurement Baseline (PMB), an important tool for keeping cost under control.
Date: December 9, 1994
Creator: Clauss, L. & Chang, D.
System: The UNT Digital Library
ROOM: A recursive object oriented method for information systems development (open access)

ROOM: A recursive object oriented method for information systems development

Although complementary for the development of complex systems, top-down structured design and object oriented approach are still opposed and not integrated. As the complexity of the systems are still growing, and the so-called software crisis still not solved, it is urgent to provide a framework mixing the two paradigms. This paper presents an elegant attempt in this direction through our Recursive Object-Oriented Method (ROOM) in which a top-down approach divides the complexity of the system and an object oriented method studies a given level of abstraction. Illustrating this recursive schema with a simple example, we demonstrate that we achieve the goal of creating loosely coupled and reusable components.
Date: February 9, 1994
Creator: Thelliez, T. & Donahue, S.
System: The UNT Digital Library
{sup 9}Be and {sup 11}B NMR study of superconductivity in boron doped UBe{sub 13} (open access)

{sup 9}Be and {sup 11}B NMR study of superconductivity in boron doped UBe{sub 13}

We present {sup 9}Be and {sup 11}B NMR spin-lattice relaxation rate (1/T{sub 1}) measurements in UBe{sub 13-x}B{sub x} for x = 0.03 and 0.07 over the temperature range 0.096 K to 2 K. The temperature dependence of 1/T{sub 1} shows a strong B concentration dependence, especially at low temperatures. We interpret this behavior as consistent with gapless superconductivity induced by the addition of B impurities. The ratio of the {sup 9}Be to {sup 11}B 1/T{sub 1} increases with decreasing temperature below {Tc} indicating additional contributions to the {sup 9}Be relaxation rate, possibly from nuclear spin diffusion to normal-state vortex cores or paramagnetic impurities.
Date: June 9, 1994
Creator: Ahrens, E. T.; Heffner, R. H.; Hammel, P. C.; Reyes, A. P.; Smith, J. L. & Clark, W. G.
System: The UNT Digital Library
The spin observables of electron-nucleon scattering from the formalism of nucleon-nucleon scattering (open access)

The spin observables of electron-nucleon scattering from the formalism of nucleon-nucleon scattering

The eN scattering spin observables are derived from the long established NN scattering formalism. Some conditions on the eN observables emerge more transparently than from the specific eN calculations themselves.
Date: March 9, 1994
Creator: Conzett, H. E.
System: The UNT Digital Library
New hollow-cathode electrode for high-power copper lasers (open access)

New hollow-cathode electrode for high-power copper lasers

Multiple hollow-cathode slots were utilized on a profiled solid-copper electrode taht extended stable glow discharge to higher pressures in copper lasers. This novel electrode design, which dramatically reduced discharge jitter and window contamination, has been run for more than 8000 hours with very little degradation.
Date: March 9, 1994
Creator: Chang, J. J.; Alger, T. W.; Anderson, A. T. & Arnold, P. A.
System: The UNT Digital Library
An investigation of genetic operators for continuous parameter space (open access)

An investigation of genetic operators for continuous parameter space

The success of a genetic optimization algorithm in continuous parameter space depends on the recombination (crossover) operators that it uses. In this paper we consider a wide spectrum of such operators within a unified framework and study their relative importance in the search process. We consider four basic types recombination operators which cover the relevant exploration potential of a continuous space: Interpolation, Extrapolation, Exchange and Mutation. Each of these basic types may have several variants. We characterize the various operators and their variants by their spatial sampling properties and examine their contributions to the search by applying different mixtures of the operators in several benchmark problems. The results suggest that the optimal mixture of operators may depend on the problem. But, in general, all basic types are needed for efficient optimization.
Date: March 9, 1994
Creator: Grossman, T. & Davidor, Y.
System: The UNT Digital Library
Recent progress in the photovoltaic manufacturing technology project (PVMaT) (open access)

Recent progress in the photovoltaic manufacturing technology project (PVMaT)

The Photovoltaic Manufacturing Technology (PVMaT) Project was initiated in 1990 to help the US photovoltaic (PV) industry extend its world leadership role in manufacturing and commercially developing PV modules and systems. It is being conducted in several phases, staggered to support industry progress. The four most recently awarded subcontracts (Phase 2B) are now completing their first year of research. They include two subcontracts on CdTe, one on Spheral Solar[trademark] Cells, and one on cast polysilicon. These subcontracts represent new technology additions to the PVMaT Project. Subcontracts initiated in earlier phases are nearing completion, and their progress is summarized. An additional phase of PVMaT, Phase 4A, is being initiated which will emphasize product-driven manufacturing research and development. The intention of Phase 4A is to emphasize improvement and cost reduction in the manufacture of full-system PV products. The work areas may include, but are not limited to, issues such as improvement of module manufacturing processes; system and system component packaging, integration, manufacturing, and assembly; product manufacturing flexibility; and balance-of-system development with the goal of product manufacturing improvements.
Date: December 9, 1994
Creator: Witt, C. E.; Mitchell, R. L.; Thomas, H.; Herwig, L. O.; Ruby, D. & Sellers, R.
System: The UNT Digital Library
Tritium release behavior or SIBELIUS beryllium (open access)

Tritium release behavior or SIBELIUS beryllium

Tritium-release kinetics studies have been conducted on eight beryllium specimen disks, irradiated in the European Community/United States of America (EC/USA) Collaborative SIBELIUS irradiation test. These studies, measuring tritium-release rate versus time over several temperatures, have generated a series of well-characterized tritium release curves. These release curves are presented, along with supporting information, to provide input data in support of tritium transport prediction models and code development.
Date: June 9, 1994
Creator: Baldwin, D.L.
System: The UNT Digital Library
Base hydrolysis and supercritical water oxidation of PBX-9404 (open access)

Base hydrolysis and supercritical water oxidation of PBX-9404

Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. The authors also examine products from the subsequent hydrothermal treatment of the base hydrolysate. The gases produced from hydrolysis of PBX-9404 are ammonia, nitrous oxide, and nitrogen. Major aqueous products are sodium formate, acetate, nitrate, and nitrite, but not all carbon products have been identified. Hydrothermal processing of base hydrolysate destroyed up to 98% of the organic carbon in solution, and higher destruction efficiencies are possible. Major gas products detected from hydrothermal processing were nitrogen and nitrous oxide.
Date: November 9, 1994
Creator: Flesner, R. L.; Spontarelli, T.; Dell`Orco, P. C.; Kramer, J. F. & Sanchez, J. A.
System: The UNT Digital Library
Shock-Wave Behavior in Explosive Monocrystals (open access)

Shock-Wave Behavior in Explosive Monocrystals

The shock response of explosive monocrystals is strongly anisotropic. Shock initiation sensitivity depends strongly on crystal orientation in PETN. This can be understood in terms of steric hindrance to shear during the shock-induced deformation of the molecular crystal. This initiation mechanism appears to be tribochemical rather than thermal.
Date: September 9, 1994
Creator: Dick, Jerry Joel
System: The UNT Digital Library
An approximate algorithm for the flux from a rectangular volume source (open access)

An approximate algorithm for the flux from a rectangular volume source

An exact semi-analytic formula for the flux from a rectangular surface source with a slab shield has been derived and the required function table has been calculated. This formula is the basis for an algorithm which gives a good approximation for the flux from a rectangular volume source. No other hand calculation method for this source geometry is available in the literature.
Date: November 9, 1994
Creator: Wallace, O. J.
System: The UNT Digital Library
Thermodynamic characterization of new palladium alloy tritides (open access)

Thermodynamic characterization of new palladium alloy tritides

The decay of tritium in a metal tritide generates {sup 3}He in the lattice which tends to degrade the performance of the material over time. It is desired to develop a material which minimizes the tritium aging effects and may be tailored to a particular tritium processing application. Pd alloys with Ni and Co have been investigated, as Pd tritide is known to be resistant to tritium aging effects and alloying provides a means for adjusting the plateau pressure of the metal tritide. Sets of tritium desorption isotherms were acquired at temperatures between 273 and 338 K over the pressure range of 1 to 900 kPa. The thermodynamic parameters of {Delta}H and {Delta}S for the {beta}-{alpha} phase transition of the metal tritides were determined across the plateau regions of the P-C-T curves. The average values of {Delta}H (kJ/mol{center_dot}T) and {Delta}S (J/K/mol{center_dot}T) were found to be 15.8 and 50.1 for Pd(2.8 wt. %)Ni, 13.7 and 50.3 for Pd(5.2 wt. %)Ni, 15.9 and 51.3 for Pd(2.8 wt. %)Co, and 13.6 and 51.8 for Pd(5.2 wt. %)Co, respectively.
Date: August 9, 1994
Creator: Hoelder, J. S. & Wermer, J. R.
System: The UNT Digital Library
New strong interactions above the electroweak scale (open access)

New strong interactions above the electroweak scale

Theoretical arguments for a new higher-color quark sector, based on Pomeron physics in QCD, are briefly described. The electroweak symmetry-breaking, Strong CP conservation, and electroweak scale CP violation, that is naturally produced by this sector is also outlined. A further consequence is that above the electroweak scale there will be a radical change in the strong interaction. Electroweak states, in particular multiple W`s and Z`s, and new, semi-stable, very massive, baryons, will be commonly produced. The possible correlation of expected phenomena with a wide range of observed Cosmic Ray effects at and above the primary spectrum knee is described. Related phenomena that might be seen in the highest energy hard scattering events at the Fermilab Tevatron, some of which could be confused with top production, are also briefly discussed.
Date: August 9, 1994
Creator: White, A. R.
System: The UNT Digital Library
New applications of copper vapor lasers in micromachining (open access)

New applications of copper vapor lasers in micromachining

We have developed a copper vapor laser based micromachinig system using advanced beam quality control and precision wavefront tilting technologies. Precision microdrilling has been demonstrated through percussion drilling and trepanning using this system. With a 30-W copper vapor from running at multi-kHz pulse repetition frequency, straight parallel holes with size varying from 500 microns to less than 25 microns and with aspect ratio up to 1:40 have been consistently drilled with good surface finish on a variety of metals. Micromilling and microdrilling on ceramics using a 250-W copper vapor laser have also been demonstrated with good result. Materialographic sections of machined parts show little (submicron scale) recast layer and heat affected zone.
Date: November 9, 1994
Creator: Chang, J. J.; Martinez, M. W.; Warner, B. E.; Dragon, E. P.; Huete, G. & Solarski, M. E.
System: The UNT Digital Library
Multiple-beam pulse shaping and preamplification (open access)

Multiple-beam pulse shaping and preamplification

Glass fusion laser systems typically use a master oscillator-power amplifier (MOPA) architecture, where control of the optical pulse temporal and spatial parameters is accomplished mainly in the master oscillator and low power optics. The pulses from this low power ``front end`` are amplified in the power amplifier, which modifies the pulse shape temporally and spatially. Nonlinear frequency conversion crystals following the amplifier further change the pulse before it reaches the target. To effectively control the optical pulse on target for different types of experiments, and compensate for nonlinearity in the preceding optics, the front end system must be versatile enough to easily control many pulse parameters over a large range. The front end pulse generation system described in this article represents a new approach to this problem. The proposed National Ignition Facility (NIF) has 192 beamlines, each of which requires an input pulse of up to 12 Joules in around 4 ns equivalent square pulse length. Considerations of laser architecture for supplying each of these beamlines from a central oscillator system were crucial in the design of the front end. Previous lasers have used bulk optics to split a single oscillator signal and report beams to multiple amplifier chains. A …
Date: November 9, 1994
Creator: Wilcox, R. B.; VanWonterghem, B. W.; Burkhart, S. C. & Davin, J. M.
System: The UNT Digital Library
Non-equilibrium dynamics in superconducting tunnel junction detectors (open access)

Non-equilibrium dynamics in superconducting tunnel junction detectors

Superconducting tunnel junctions have the potential to serve as high-resolution, high-efficiency x-ray detectors for astrophysical and industrial applications. When irradiated by X rays, each X ray excites over 10{sup 6} charge carriers which cause the detector to generate a pulse of current. We present an analysis of pulse shapes from detectors we have constructed and operated. We fit the decay of the current pulse to a simple model that considers two classes of carrier loss. One model considers only the normal recombination of the charge carriers with themselves, the other included additional losses due to recombination sites in the within the detector medium. We found that both mechanisms most be taken into account. We also found a small variation in pulse shape depending on which layer of the tunnel junction absorbed the X ray. We expect that this analysis will be a useful tool in comparing different detector designs and operating conditions.
Date: December 9, 1994
Creator: Hiller, L. J.; Labov, S. E.; Mears, C. A.; Frank, M.; Bello, A. F. & Barfknecht, A. T.
System: The UNT Digital Library