ELECTRICAL SUBSTATION RELIABILITY EVALUATION WITH EMPHASIS ON EVOLVING INTERDEPENDENCE ON COMMUNICATION INFRASTRUCTURE. (open access)

ELECTRICAL SUBSTATION RELIABILITY EVALUATION WITH EMPHASIS ON EVOLVING INTERDEPENDENCE ON COMMUNICATION INFRASTRUCTURE.

The objective of this study is to develop a methodology for a probabilistic assessment of the reliability and security of electrical energy distribution networks. This includes consideration of the future grid system, which will rely heavily on the existing digitally based communication infrastructure for monitoring and protection. Another important objective of this study is to provide information and insights from this research to Consolidated Edison Company (Con Edison) that could be useful in the design of the new network segment to be installed in the area of the World Trade Center in lower Manhattan. Our method is microscopic in nature and relies heavily on the specific design of the portion of the grid being analyzed. It extensively models the types of faults that a grid could potentially experience, the response of the grid, and the specific design of the protection schemes. We demonstrate that the existing technology can be extended and applied to the electrical grid and to the supporting communication network. A small subsection of a hypothetical grid based on the existing New York City electrical grid system of Con Edison is used to demonstrate the methods. Sensitivity studies show that in the current design the frequency for the …
Date: January 15, 2004
Creator: AZARM,M. A. BARI,R. A. MUSICKI,Z.
Object Type: Report
System: The UNT Digital Library
Exotic physics: search for doubly-charged higgs bosons decaying to dileptons in p anti-p collisions at s**(1/2) = 1.96 tev (open access)

Exotic physics: search for doubly-charged higgs bosons decaying to dileptons in p anti-p collisions at s**(1/2) = 1.96 tev

The authors present the results of a search for doubly-charged Higgs bosons (H{sup {+-}}{sup {+-}}) decaying to dileptons (ll') using {approx} 240 pb{sup -1} of p{bar p} collision data collected by the CDF II experiment at the Fermilab Tevatron. In the search region, given by same-sign ll' mass m{sub ll'} > 80 GeV/c{sup 2} (100 GeV/c{sup 2} for ee channel), they observe no evidence for H{sup {+-}}{sup {+-}} production. They set limits on {sigma}(p{bar p} {yields} H{sup ++}H{sup --} {yields} l{sup +}l'{sup +}l{sup -}l'{sup -}) as a function of the mass of the H{sup {+-}}{sup {+-}} and the chirality of its couplings. Assuming exclusive same-sign dilepton decays, they derive lower mass limits on H{sub L}{sup {+-}}{sup {+-}} of 133 GeV/c{sup 2}, 136 GeV/c{sup 2}, and 115 GeV/c{sup 2} in the ee, {mu}{mu}, and e{mu} channels, respectively, and a lower mass limit of 113 GeV/c{sup 2} on H{sub R}{sup {+-}}{sup {+-}} in the {mu}{mu} channel, all at the 95% confidence level.
Date: November 15, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV (open access)

Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and -1 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > p{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured p{sub T} region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.
Date: April 15, 2004
Creator: Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Object Type: Article
System: The UNT Digital Library
Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub t} in Au+Au collisions at {radical}s{sub NN} = 130 GeV (open access)

Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub t} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and 11 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > P{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured pT region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.
Date: April 15, 2004
Creator: Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Object Type: Article
System: The UNT Digital Library
Boundary Layer Cloudiness Parameterizations Using ARM Observations (open access)

Boundary Layer Cloudiness Parameterizations Using ARM Observations

This study used DOE ARM data and facilities to: (1) study macroscopic properties of continental stratus clouds at SGP and the factors controlling these properties, (2) develop a scientific basis for understanding the processes responsible for the formation of boundary layer clouds using ARM observations in conjunction with simple parametric models and LES, and (3) evaluate cumulus cloud characteristics retrieved from the MMCR operating at TWP-Nauru. In addition we have used high resolution 94 GHz observations of boundary layer clouds and precipitation to: (1) develop techniques for using high temporal resolution Doppler velocities to study large-eddy circulations and turbulence in boundary layer clouds and estimate the limitations of using current and past MMCR data for boundary layer cloud studies, (2) evaluate the capability and limitations of the current MMCR data for estimating reflectivity, vertical velocities, and spectral under low- signal-to-noise conditions associated with weak no n-precipitating clouds, (3) develop possible sampling modes for the new MMCR processors to allow for adequate sampling of boundary layer clouds, and (4) retrieve updraft and downdraft structures under precipitating conditions.
Date: September 15, 2004
Creator: Albrecht, Bruce
Object Type: Report
System: The UNT Digital Library
VELOCITY BUNCHING OF HIGH-BRIGHTNESS ELECTRON BEAMS (open access)

VELOCITY BUNCHING OF HIGH-BRIGHTNESS ELECTRON BEAMS

Velocity bunching has been recently proposed as a tool for compressing electron beam pulses in modern high brightness photoinjector sources. This tool is familiar from earlier schemes implemented for bunching dc electron sources, but presents peculiar challenges when applied to high current, low emittance beams from photoinjectors. The main difficulty foreseen is control of emittance oscillations in the beam in this scheme, which can be naturally considered as an extension of the emittance compensation process at moderate energies. This paper presents two scenarios in which velocity bunching, combined with emittance control, is to play a role in nascent projects. The first is termed ballistic bunching, where the changing of relative particle velocities and positions occur in distinct regions, a short high gradient linac, and a drift length. This scenario is discussed in the context of the proposed ORION photoinjector. Simulations are used to explore the relationship between the degree of bunching, and the emittance compensation process. Experimental measurements performed at the UCLA Neptune Laboratory of the surprisingly robust bunching process, as well as accompanying deleterious transverse effects, are presented. An unanticipated mechanism for emittance growth in bends for highly momentum chirped beam was identified and studied in these experiments. The …
Date: October 15, 2004
Creator: Anderson, S. G.; Musumeci, P.; Rosenzweig, J. B.; Brown, W. J.; England, R. J.; Ferrario, M. et al.
Object Type: Article
System: The UNT Digital Library
Heavy Meson Production at a Low-Energy Photon Collider (open access)

Heavy Meson Production at a Low-Energy Photon Collider

A low-energy {gamma}{gamma} collider has been discussed in the context of a testbed for a {gamma}{gamma} interaction region at the Next Linear Collider(NLC). We consider the production of heavy mesons at such a testbed using Compton-backscattered photons and demonstrate that their production rivals or exceeds those by BELLE, BABAR or LEP where they are produced indirectly via virtual {gamma}{gamma} luminosities.
Date: April 15, 2004
Creator: Asztalos, S
Object Type: Article
System: The UNT Digital Library
Commercial Demonstration of Wood Recovery, Recycling, and Value Adding Technologies (open access)

Commercial Demonstration of Wood Recovery, Recycling, and Value Adding Technologies

This commercial demonstration project demonstrated the technical feasibility of converting low-value, underutilized and waste stream solid wood fiber material into higher valued products. With a growing need to increase product/production yield and reduce waste in most sawmills, few recovery operations and practically no data existed to support the viability of recovery operations. Prior to our efforts, most all in the forest products industry believed that recovery was difficult, extremely labor intensive, not cost effective, and that recovered products had low value and were difficult to sell. This project provided an opportunity for many within the industry to see through demonstration that converting waste stream material into higher valued products does in fact offer a solution. Our work, supported by the U.S. Department of Energy, throughout the project aimed to demonstrate a reasonable approach to reducing the millions of recoverable solid wood fiber tons that are annually treated as and converted into low value chips, mulch and fuel. Consequently sawmills continue to suffer from reduced availability of forest resources, higher raw material costs, growing waste disposal problems, increased global competition, and more pressure to operate in an Environmentally Friendly manner. It is our belief (based upon the experience of this project) …
Date: July 15, 2004
Creator: Auburn Machinery, Inc.
Object Type: Report
System: The UNT Digital Library
Facility Effluent Monitoring Plan for Pacific Northwest National Laboratory Balance-of-Plant Facilities (open access)

Facility Effluent Monitoring Plan for Pacific Northwest National Laboratory Balance-of-Plant Facilities

The Pacific Northwest National Laboratory (PNNL) operates a number of Research & Development (R&D) facilities for the U.S. Department of Energy (DOE) on the Hanford Site. Facility effluent monitoring plans (FEMPs) have been developed to document the facility effluent monitoring portion of the Environmental Monitoring Plan (DOE 2000) for the Hanford Site. Three of PNNL’s R&D facilities, the 325, 331, and 3720 Buildings, are considered major emission points for radionuclide air sampling, and individual FEMPs were developed for these facilities in the past. In addition, a balance-of-plant (BOP) FEMP was developed for all other DOE-owned, PNNL-operated facilities at the Hanford Site. Recent changes, including shutdown of buildings and transition of PNNL facilities to the Office of Science, have resulted in retiring the 3720 FEMP and combining the 331 FEMP into the BOP FEMP. This version of the BOP FEMP addresses all DOE-owned, PNNL-operated facilities at the Hanford Site, excepting the Radiochemical Processing Laboratory, which has its own FEMP because of the unique nature of the building and operations. Activities in the BOP facilities range from administrative to laboratory and pilot-scale R&D. R&D activities include both radioactive and chemical waste characterization, fluid dynamics research, mechanical property testing, dosimetry research, and molecular …
Date: November 15, 2004
Creator: Ballinger, Marcel Y. & Gervais, Todd L.
Object Type: Report
System: The UNT Digital Library
Freeeze-Out Dynamics at RHIC. (open access)

Freeeze-Out Dynamics at RHIC.

Investigation of the final hadronic state properties of ultra-relativistics pp and Au+Au collisions supplies information on freeze-out conditions at RHIC and possible insights into early stages of these collisions. A variety of particle spectra measured by STAR are studied within the framework of chemical and local kinetic equilibrium models. Here we present the extracted chemical and final kinetic freeze-out temperatures, strangeness saturation factor, final collective flow velocity, and the inferred flow velocity at chemical freeze-out. In light of those measurements we discuss dynamical evolution of the collision system.
Date: March 15, 2004
Creator: Barannikova, O.
Object Type: Article
System: The UNT Digital Library
A Final Focus Model for Heavy Ion Fusion Driver System Codes (open access)

A Final Focus Model for Heavy Ion Fusion Driver System Codes

The need to reach high temperatures in an inertial fusion energy (IFE) target (or a target for the study of High Energy Density Physics, HEDP) requires the ability to focus ion beams down to a small spot. System models indicate that within the accelerator, the beam radius will be of order centimeters, whereas at the final focal spot on the target, a beam radius of order millimeters is required, so radial compression factors of order ten are required. The IFE target gain (and hence the overall cost of electricity) and the HEDP target temperature are sensitive functions of the final spot radius on target. Because of this sensitivity, careful attention needs to be paid to the spot radius calculation. We review our current understanding of the elements that enter into a systems model (such as emittance growth from chromatic, geometric, and non-linear space charge forces) for the final focus based on a quadrupolar magnet system.
Date: December 15, 2004
Creator: Barnard, J. J.; Bangerter, R. O.; Henestroza, E.; Kaganovich, I. D.; Logan, B. G.; Meier, W. R. et al.
Object Type: Article
System: The UNT Digital Library
Design Issues for the Superconducting Magnet that Goes Around theLiquid Hydrogen Absorber for the Muon Ionization Cooling Experiment(MICE) (open access)

Design Issues for the Superconducting Magnet that Goes Around theLiquid Hydrogen Absorber for the Muon Ionization Cooling Experiment(MICE)

This report describes the design issues that are associated with a superconducting focusing solenoid that goes around a liquid hydrogen absorber for the Muon Ionization Cooling Experiment (MICE) proposed for the Rutherford Appleton Laboratory. The solenoid consists of two superconducting coils that may operated at the same polarity or at opposite polarities. As a result, the coils and their support structure must be designed to carry a 360-ton inter-coil force that is forcing the coils apart along their axis. The basic design parameters for the focusing magnet are discussed. The magnet and its cryostat are designed so that the absorber can be assembled and tested before installation into the pre-tested focusing solenoid. Safety requirements for MICE dictate that the insulating vacuum for the superconducting magnet be separated from the insulating vacuum for the absorber and that both vacuum be separated from the experiment vacuum and the vacuum within adjacent RF cavities. The safety issues associated with the arrangement of the various vacuums in the MICE focusing modules are presented. The effect of magnet operation and magnet quench on the liquid hydrogen absorber is also discussed.
Date: June 15, 2004
Creator: Barr, G.; Cobb, J. H.; Green, M. A.; Lau, W.; R. S., Senanayake; Yang, S. Q. et al.
Object Type: Article
System: The UNT Digital Library
Affordable Window Insulation with R-10/inch Rating (open access)

Affordable Window Insulation with R-10/inch Rating

During the performance of contract DE-FC26-00-NT40998, entitled ''Affordable Window Insulation with R-10/inch Value'', research was conducted at Aspen Aerogels, Inc. to develop new transparent aerogel materials suitable for window insulation applications. The project requirements were to develop a formulation or multiple formulations that have high transparency (85-90%) in the visible region, are hydrophobic (will not opacify with exposure to water vapor or liquid), and have at least 2% resiliency (interpreted as recoverable 2% strain and better than 5% strain to failure in compression). Results from an unrelated project showed that silica aerogels covalently bonded to organic polymers exhibit excellent mechanical properties. At the outset of this project, we believed that such a route is the best to improve mechanical properties. We have applied Design of Experiment (DOE) techniques to optimize formulations including both silica aerogels and organically modified silica aerogels (''Ormosils''). We used these DOE results to optimize formulations around the local/global optimization points. This report documents that we succeeded in developing a number of formulations that meet all of the stated criteria. We successfully developed formulations utilizing a two-step approach where the first step involves acid catalyzed hydrolysis and the second step involves base catalyzed condensation to make the …
Date: October 15, 2004
Creator: Begag, Jenifer Marchesi Redouane; Lee, Je Kyun; Ou, Danny; Sonn, Jong Ho; Gould, George & Rhine, Wendell
Object Type: Report
System: The UNT Digital Library
Pore Fluid Effects on Shear Modulus for Sandstones with Soft Anisotropy (open access)

Pore Fluid Effects on Shear Modulus for Sandstones with Soft Anisotropy

A general analysis of poroelasticity for vertical transverse isotropy (VTI) shows that four eigenvectors are pure shear modes with no coupling to the pore-fluidmechanics. The remaining two eigenvectors are linear combinations of pure compression and uniaxial shear, both of which are coupled to the fluid mechanics. After reducing the problem to a 2x2 system, the analysis shows in a relatively elementary fashion how a poroelastic system with isotropic solid elastic frame, but with anisotropy introduced through the poroelastic coefficients, interacts with the mechanics of the pore fluid and produces shear dependence on fluid properties in the overall mechanical system. The analysis shows, for example, that this effect is always present (though sometimes small in magnitude) in the systems studied, and can be quite large (up to a definite maximum increase of 20 per cent) in some rocks--including Spirit River sandstone and Schuler-Cotton Valley sandstone.
Date: April 15, 2004
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
The frequency and damping of ion acoustic waves in collisional and collisionless two-species plasma (open access)

The frequency and damping of ion acoustic waves in collisional and collisionless two-species plasma

The dispersion properties of ion acoustic waves (IAW) are sensitive to the strength of ion-ion collisions in multi-species plasma in which the different species usually have differing charge-to-mass ratios. The modification of the frequency and damping of the fast and slow acoustic modes in a plasma composed of light (low Z) and heavy (high Z) ions is considered. In the fluid limit where the light ion scattering mean free path, {lambda}{sub th} is smaller than the acoustic wavelength, {lambda} = 2{pi}/k, the interspecies friction and heat flow carried by the light ions scattering from the heavy ions causes the damping. In the collisionless limit, k{lambda}{sub lh} >> 1, Landau damping by the light ions provides the dissipation. In the intermediate regime when k{lambda}{sub lh} {approx} 1, the damping is at least as large as the sum of the collisional and Landau damping.
Date: July 15, 2004
Creator: Berger, R L & Valeo, E J
Object Type: Article
System: The UNT Digital Library
Elemental Composition of a Composite of Samples HTF-E-03-162 to 164 From Tank 51H to Evaluate Acceptability of the Sludge for Transfer to Tank 40H and Processing in the DWPF (open access)

Elemental Composition of a Composite of Samples HTF-E-03-162 to 164 From Tank 51H to Evaluate Acceptability of the Sludge for Transfer to Tank 40H and Processing in the DWPF

Three dip samples of suspended sludge slurry were obtained from Tank 51H and sent to the Savannah River Technology Center for analysis. The composite of these samples is intended as a confirmatory sample to evaluate the acceptability of the Tank 51H sludge slurry for transfer to Tank 40H and for eventual processing in the Defense Waste Processing Facility. This report presents results of analyses requested by the Defense Waste Processing Facility for this evaluation. These analyses included the measurement of the concentrations of twenty two elements in the sludge slurry and the determination of the weight percent calcined solids of the slurry.
Date: April 15, 2004
Creator: Bibler, N. E.
Object Type: Report
System: The UNT Digital Library
Vacuum Technology (open access)

Vacuum Technology

The environmental condition called vacuum is created any time the pressure of a gas is reduced compared to atmospheric pressure. On earth we typically create a vacuum by connecting a pump capable of moving gas to a relatively leak free vessel. Through operation of the gas pump the number of gas molecules per unit volume is decreased within the vessel. As soon as one creates a vacuum natural forces (in this case entropy) work to restore equilibrium pressure; the practical effect of this is that gas molecules attempt to enter the evacuated space by any means possible. It is useful to think of vacuum in terms of a gas at a pressure below atmospheric pressure. In even the best vacuum vessels ever created there are approximately 3,500,000 molecules of gas per cubic meter of volume remaining inside the vessel. The lowest pressure environment known is in interstellar space where there are approximately four molecules of gas per cubic meter. Researchers are currently developing vacuum technology components (pumps, gauges, valves, etc.) using micro electro mechanical systems (MEMS) technology. Miniature vacuum components and systems will open the possibility for significant savings in energy cost and will open the doors to advances in …
Date: October 15, 2004
Creator: Biltoft, P. J.
Object Type: Book
System: The UNT Digital Library
Intra-species sequence comparisons for annotating genomes (open access)

Intra-species sequence comparisons for annotating genomes

Analysis of sequence variation among members of a single species offers a potential approach to identify functional DNA elements responsible for biological features unique to that species. Due to its high rate of allelic polymorphism and ease of genetic manipulability, we chose the sea squirt, Ciona intestinalis, to explore intra-species sequence comparisons for genome annotation. A large number of C. intestinalis specimens were collected from four continents and a set of genomic intervals amplified, resequenced and analyzed to determine the mutation rates at each nucleotide in the sequence. We found that regions with low mutation rates efficiently demarcated functionally constrained sequences: these include a set of noncoding elements, which we showed in C intestinalis transgenic assays to act as tissue-specific enhancers, as well as the location of coding sequences. This illustrates that comparisons of multiple members of a species can be used for genome annotation, suggesting a path for the annotation of the sequenced genomes of organisms occupying uncharacterized phylogenetic branches of the animal kingdom and raises the possibility that the resequencing of a large number of Homo sapiens individuals might be used to annotate the human genome and identify sequences defining traits unique to our species. The sequence data …
Date: July 15, 2004
Creator: Boffelli, Dario; Weer, Claire V.; Weng, Li; Lewis, Keith D.; Shoukry, Malak I.; Pachter, Lior et al.
Object Type: Article
System: The UNT Digital Library
Complete mitochondrial genome sequence of the polychaete annelidPlatynereis dumerilii (open access)

Complete mitochondrial genome sequence of the polychaete annelidPlatynereis dumerilii

Complete mitochondrial genome sequences are now available for 126 metazoans (see Boore 1999; Mitochondrial Genomics link at http://www.jgi.doe.gov), but the taxonomic representation is highly biased. For example, 80 are from a single phylum, Chordata, and show little variation for many molecular features. Arthropoda is represented by 16 taxa, Mollusca by eight, and Echinodermata by five, with only 17 others from the remaining {approx}30 metazoan phyla. With few exceptions (see Wolstenholme 1992 and Boore 1999) these are circular DNA molecules, about 16 kb in size, and encode the same set of 37 genes. A variety of non-standard names are sometimes used for animal mitochondrial genes; see Boore (1999) for gene nomenclature and a table of synonyms. Mitochondrial genome comparisons serve as a model of genome evolution. In this system, much smaller and simpler than that of the nucleus, are all of the same factors of genome evolution, where one may find tractable the changes in tRNA structure, base composition, genetic code, gene arrangement, etc. Further, patterns of mitochondrial gene rearrangements are an exceptionally reliable indicator of phylogenetic relationships (Smith et al.1993; Boore et al. 1995; Boore, Lavrov, and Brown 1998; Boore and Brown 1998, 2000; Dowton 1999; Stechmann and Schlegel 1999; …
Date: August 15, 2004
Creator: Boore, Jeffrey L.
Object Type: Article
System: The UNT Digital Library
Understanding the Relationship Between Filling Pattern and Part Quality in Die Casting (open access)

Understanding the Relationship Between Filling Pattern and Part Quality in Die Casting

The overall objective of this research project was to investigate phenomena involved in the filling of die cavities with molten alloy in the cold chamber die-casting process. It has long been recognized that the filling pattern of molten metal entering a die cavity influences the quality of die-cast parts. Filling pattern may be described as the progression of molten metal filling the die cavity geometry as a function of time. The location, size and geometric configuration of points of metal entry (gates), as well as the geometry of the casting cavity itself, have great influence on filling patterns. Knowledge of the anticipated filling patterns in die-castings is important for designers. Locating gates to avoid undesirable flow patterns that may entrap air in the casting is critical to casting quality - as locating vents to allow air to escape from the cavity (last places to fill). Casting quality attributes that are commonly flow related are non-fills, poor surface finish, internal porosity due to trapped air, cold shuts, cold laps, flow lines, casting skin delamination (flaking), and blistering during thermal treatment.
Date: March 15, 2004
Creator: Brevick, Jerald & Miller, R. Allen
Object Type: Report
System: The UNT Digital Library
Energy Consumption of Die Casting Operations (open access)

Energy Consumption of Die Casting Operations

Molten metal processing is inherently energy intensive and roughly 25% of the cost of die-cast products can be traced to some form of energy consumption [1]. The obvious major energy requirements are for melting and holding molten alloy in preparation for casting. The proper selection and maintenance of melting and holding equipment are clearly important factors in minimizing energy consumption in die-casting operations [2]. In addition to energy consumption, furnace selection also influences metal loss due to oxidation, metal quality, and maintenance requirements. Other important factors influencing energy consumption in a die-casting facility include geographic location, alloy(s) cast, starting form of alloy (solid or liquid), overall process flow, casting yield, scrap rate, cycle times, number of shifts per day, days of operation per month, type and size of die-casting form of alloy (solid or liquid), overall process flow, casting yield, scrap rate, cycle times, number of shifts per day, days of operation per month, type and size of die-casting machine, related equipment (robots, trim presses), and downstream processing (machining, plating, assembly, etc.). Each of these factors also may influence the casting quality and productivity of a die-casting enterprise. In a die-casting enterprise, decisions regarding these issues are made frequently and …
Date: March 15, 2004
Creator: Brevick, Jerald; Mount-Campbell, clark & Mobley, Carroll
Object Type: Report
System: The UNT Digital Library
User's guide to fete: From ENDF/B-VI To ENDL (open access)

User's guide to fete: From ENDF/B-VI To ENDL

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Date: September 15, 2004
Creator: Brown, D. A.; Hedstrom, G. & Hill, T.
Object Type: Text
System: The UNT Digital Library
Proposal for ENDF formats that describe emission of post-fission beta-delayed photons (open access)

Proposal for ENDF formats that describe emission of post-fission beta-delayed photons

Fission of heavy nuclides is accompanied by the birth of neutron rich fragment nuclei born in highly excited states. Following emission of prompt neutrons and {gamma}-rays, these fragments are typically left with atomic numbers that are 3-4 units smaller than stable nuclei with the same mass number. As these nuclides undergo {beta} decay to reach stability, a large number of {gamma}-rays are emitted. Figure 1 illustrates some of the processes leading to emission of {beta} delayed photons. A variety of applications (most notably those concerned with the detection and identification of clandestine fissile material) would benefit from a clear description of the spectral and temporal evolution of these {gamma}-rays. This proposal describes formats for representing emission of delayed photons and is based on the analysis presented in. At the present time, no single evaluated data set exists that directly provides for the temporal evolution of {gamma} rays from the decay of the fission products. However, evaluated data sets containing all of the physical parameters required for such calculations have been prepared. These include estimates of the independent and cumulative fission yields of all fission products, branching ratios in the decay of ground and isomeric states, lifetimes of these states, and …
Date: September 15, 2004
Creator: Brown, David; Pruet, Jason; Hedstrom, Gerry; Hall, James & Descalle, Marie-anne
Object Type: Report
System: The UNT Digital Library
Plasma Deposited Diamond-Like Carbon Films for Large Neutralarrays (open access)

Plasma Deposited Diamond-Like Carbon Films for Large Neutralarrays

To understand how large systems of neurons communicate, we need to develop methods for growing patterned networks of large numbers of neurons. We have found that diamond-like carbon thin films formed by energetic deposition from a filtered vacuum arc carbon plasma can serve as ''neuron friendly'' substrates for the growth of large neural arrays. Lithographic masks can be used to form patterns of diamond-like carbon, and regions of selective neuronal attachment can form patterned neural arrays. In the work described here, we used glass microscope slides as substrates on which diamond-like carbon was deposited. PC-12 rat neurons were then cultured on the treated substrates and cell growth monitored. Neuron growth showed excellent contrast, with prolific growth on the treated surfaces and very low growth on the untreated surfaces. Here we describe the vacuum arc plasma deposition technique employed, and summarize results demonstrating that the approach can be used to form large patterns of neurons.
Date: July 15, 2004
Creator: Brown, I. G.; Blakely, E. A.; Bjornstad, K. A.; Galvin, J. E.; Monteiro, O. R. & Sangyuenyongpipat, S.
Object Type: Article
System: The UNT Digital Library