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Workshop on environmental control technology for The Geysers-Calistoga KGRA (open access)

Workshop on environmental control technology for The Geysers-Calistoga KGRA

The proceedings of six work groups that discussed techniques to prevent and abate noise, hydrogen sulfide emissions, and accidental spills of chemicals and geothermal wastes at The Geysers-Calistoga KGRA are reported. Problems associated with well completion and production, and with systems, components, and materials, and their effects on emissions were also discussed. The comments and recommendations of the work groups are included in the proceedings. (MHR)
Date: January 28, 1980
Creator: Hill, J. H. & Phelps, P. L.
System: The UNT Digital Library
Dielectric Wakefield Accelerator Experiments at the SABER Facility (open access)

Dielectric Wakefield Accelerator Experiments at the SABER Facility

Electron bunches with the unparalleled combination of high charge, low emittances, and short time duration, as first produced at the SLAC Final Focus Test Beam (FFTB), are foreseen to be produced at the SABER facility. These types of bunches have enabled wakefield driven accelerating schemes of multi-GV/m in plasmas. In the context of the Dielectric Wakefield Accelerators (DWA) such beams, having rms bunch length as short as 20 um, have been used to drive 100 um and 200 um ID hollow tubes above 20 GV/m surface fields. These FFTB tests enabled the measurement of a breakdown threshold in fused silica (with full data analysis still ongoing) [1]. With the construction and commissioning of the SABER facility at SLAC, new experiments would be made possible to test further aspects of DWAs including materials, tube geometrical variations, direct measurements of the Cerenkov fields, and proof of acceleration in tubes >10 cm in length. This collaboration will investigate breakdown thresholds and accelerating fields in new materials including CVD diamond. Here we describe the experimental plans, beam parameters, simulations, and progress to date as well as future prospects for machines based of DWA structures.
Date: January 28, 2008
Creator: Kanareykin, A.; Thompson, M. C.; Berry, M. K.; Blumenfeld, I.; Decker, F. J.; Hogan, M. J. et al.
System: The UNT Digital Library
Compound Nucleus Contributions to the Optical Potential (open access)

Compound Nucleus Contributions to the Optical Potential

An ab-initio calculation of the optical potential for neutron-nucleus scattering has been performed by explicitly coupling the elastic channel to all the particle-hole (p-h) excitation states in the target. These p-h states may be regarded as doorway states through which the flux flows to more complicated configurations, and (in the end) to long-lived compound nucleus resonances. The random-phase approximation (RPA) provides the linear combinations of p-h states that include the residual interactions within the target, and we show preliminary results for elastic flux loss using both p-h and RPA descriptions of target excitations.
Date: January 28, 2008
Creator: Thompson, I J; Dietrich, F S; Escher, J E & Dupuis, M
System: The UNT Digital Library
STAR Vertex Detector Upgrade Development (open access)

STAR Vertex Detector Upgrade Development

We report on the development and prototyping efforts undertaken with the goal of producing a micro-vertex detector for the STAR experiment at the RHIC accelerator at BNL. We present the basic detector requirements and show a sensor development path, conceptual mechanical design candidates and readout architecture. Prototyping and beam test results with current generation MimoSTAR-2 sensors and a readout system featuring FPGA based on-the-fly hit finding and data sparsification are also presented.
Date: January 28, 2008
Creator: Greiner, Leo C.; Matis, Howard S.; Stezelberger, Thorsten; Vu,Chinh Q.; Wieman, Howard; Szelezniak, Michal et al.
System: The UNT Digital Library
Meshless Solution of the Vlasov Equation Using a Low Discrepancy Sequence (open access)

Meshless Solution of the Vlasov Equation Using a Low Discrepancy Sequence

A good method for solving the nonlinear Vlasov equation is the semi-Lagrangian algorithm, in which the phase space density is represented by its values on a fixed Cartesian grid with interpolation to off-grid points. At each time step, orbits are followed backward from grid points. Since this method is expensive with phase space dimension D > 2, we seek a more efficient discretization of the density. Taking a cue from the theory of numerical quadrature in high dimensions, we explore the idea of replacing the grid by scattered data sites from a low-discrepancy (quasirandom) sequence. We hope to see a reduction in the required number of sites, especially for D > 2. In our first implementation we follow forward orbits rather than backward, and work only with D = 2. We are able to reduce the number of sites by a factor of 8, at least for a limited time of integration. A much bigger reduction is expected in higher dimensions.
Date: January 28, 2009
Creator: Warnock, R. L.; Ellison, J. A.; Heinemann, K. & Zhang, G. Q.
System: The UNT Digital Library
Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks (open access)

Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks

Foot and mouth disease (FMD) is a highly infectious and contagious viral disease affecting bovidae (cattle, zebus, domestic buffaloes, yaks), sheep, goats, swine, all wild ruminants and suidae. Camelidae (camels, dromedaries, llamas, vicunas) have low susceptibility. Foot and mouth disease is caused by a RNS virus of the family Picornaviridae, genus Aphthovirus. There are seven immunologically distinct serotypes: A, O, C, SAT1, SAT2, SAT3, Asia 1. Foot and mouth disease causes significant economic loss both to countries who manage it as an endemic disease (with or without vaccination), as well as those FMD free countries which may become infected. The mortality rate is low in adult animals, but often higher in young due to myocarditis. Foot and mouth disease is endemic in parts of Asia, Africa, the Middle East and South America (sporadic outbreaks in free areas). The Office of International Epizootics (OIE), also referred to the World Organization for Animal Health maintains an official list of free countries and zones.1 The OIE Terrestrial Code (Chapter 2.2.10) provides detailed information on the categories of freedom that can be allocated to a country as well as guidelines for the surveillance for foot and mouth disease (Appendix 3.8.7). In short, countries may …
Date: January 28, 2008
Creator: Hullinger, P
System: The UNT Digital Library
On the Possibility of Accelerating Positron on an Electron Wake at SABER (open access)

On the Possibility of Accelerating Positron on an Electron Wake at SABER

A new approach for positron acceleration in non-linear plasma wakefields driven by electron beams is presented. Positrons can be produced by colliding an electron beam with a thin foil target embedded in the plasma. Integration of positron production and acceleration in one stage is realized by a single relativistic, intense electron beam. Simulations with the parameters of the proposed SABER facility [1] at SLAC suggest that this concept could be tested there.
Date: January 28, 2008
Creator: Ischebeck, R.; Joshi, C.; Katsouleas, T. C.; Muggli, P. & Wang, X.
System: The UNT Digital Library
Correlating Pulses from Two Spitfire, 800nm Lasers (open access)

Correlating Pulses from Two Spitfire, 800nm Lasers

The E163 laser acceleration experiments conducted at SLAC have stringent requirements on the temporal properties of two regeneratively amplified, 800nm, Spitfire laser systems. To determine the magnitude and cause of timing instabilities between the two Ti:Sapphire amplifiers, we pass the two beams through a cross-correlator and focus the combined beam onto a Hamamatsu G1117 photodiode. The photodiode has a bandgap such that single photon processes are suppressed and only the second order, two-photon process produces an observable response. The response is proportional to the square of the intensity. The diode is also useful as a diagnostic to determine the optimal configuration of the compression cavity.
Date: January 28, 2008
Creator: Colby, Eric R.; Mcguinness, C.; Zacherl, W. D. & Plettner, T.
System: The UNT Digital Library
Modeling the absorption of intense, short laser pulses in steep density gradients (open access)

Modeling the absorption of intense, short laser pulses in steep density gradients

A subroutine which calculates the absorption of short pulse electromagnetic radiation in a material has been installed into the laser fusion modeling program called LASNEX. Calculational results show the necessity for NLTE physics to account for ionization, the development of non-exponential density profiles for the expanding plasma and movement of the critical point toward the surface which results in Doppler shifts of the reflected light. Comparison of calculations of local scale lengths with experiments shows not only good agreement but the correct scaling with intensity. 8 refs., 5 figs.
Date: January 28, 1991
Creator: Alley, W.E.
System: The UNT Digital Library
Minimars configuration design. [R] (open access)

Minimars configuration design. [R]

Viewgraph comprise the report. Aspects of design which are discussed are: end cell coil arrangement, neutral beam and rf injection, load definition on end cell coils, and intracoil structure for all coils. (WRF)
Date: January 28, 1986
Creator: Lousteau, D.C.
System: The UNT Digital Library
A multimegawatt space power source radiator design (open access)

A multimegawatt space power source radiator design

The multimegawatt space power sources (MMSPS) proposed for deployment in the late 1990s to meet mission burst power requirements, require an increase by four orders of magnitude in the power rating of equipment currently used in space. Prenger and Sullivan (1982) describe various radiator concepts proposed for such applications. They range from the innovative liquid droplet radiator (Mattick and Hertzberg 1981) to the more conventional heat pipe concept (Girrens 1982). The present paper deals with the design of the radiator for one such system, characterized by both high temperature and high pressure. It provides an estimate of the size, mass, and problems of orbiting such a radiator, based on the assumption that the next generation of heavy launch vehicle with 120-tonne carrying capacity, and 4000-m/sup 3/ cargo volume, will be available for putting hardware into orbit.
Date: January 28, 1988
Creator: Jedruch, J.
System: The UNT Digital Library
Body shape differences in a pair of closely related Malawi cichlids and their hybrids: Effects of genetic variation, phenotypic plasticity, and transgressive segregation (open access)

Body shape differences in a pair of closely related Malawi cichlids and their hybrids: Effects of genetic variation, phenotypic plasticity, and transgressive segregation

This article investigates the contributions of genetic and plastic components for differences in body shape in two species of Lake Malawi cichlids using wild-caught specimens and a common garden experiment.
Date: January 28, 2017
Creator: Husemann, Martin; Tobler, Michael; McCauley, Cagney; Ding, Baoqing & Danley, Patrick D.
System: The UNT Digital Library
Computer animation of clouds (open access)

Computer animation of clouds

Computer animation of outdoor scenes is enhanced by realistic clouds. I will discuss several different modeling and rendering schemes for clouds, and show how they evolved in my animation work. These include transparency-textured clouds on a 2-D plane, smooth shaded or textured 3-D clouds surfaces, and 3-D volume rendering. For the volume rendering, I will present various illumination schemes, including the density emitter, single scattering, and multiple scattering models.
Date: January 28, 1994
Creator: Max, N.
System: The UNT Digital Library
A real-time emergency response workstation using a 3-D numerical model initialized with sodar (open access)

A real-time emergency response workstation using a 3-D numerical model initialized with sodar

Many emergency response dispersion modeling systems provide simple Gaussian models driven by single meteorological tower inputs to estimate the downwind consequences from accidental spills or stack releases. Complex meteorological or terrain settings demand more sophisticated resolution of the three-dimensional structure of the atmosphere to reliably calculate plume dispersion. Mountain valleys and sea breeze flows are two common examples of such settings. To address these complexities, the authors have implemented the three-dimensional diagnostic MATHEW mass-adjusted wind field and ADPIC particle-in-cell dispersion models on a workstation for use in real-time emergency response modeling. MATHEW/ADPIC have shown their utility in a variety of complex settings over the last 15 years within the Department of Energy`s Atmospheric Release Advisory Capability (ARAC) project. The models are initialized using an array of surface wind measurements from meteorological towers coupled with vertical profiles from an acoustic sounder (sodar). The workstation automatically acquires the meteorological data every 15 minutes. A source term is generated using either defaults or a real-time stack monitor. Model outputs include contoured isopleths displayed on site geography or plume densities shown over 3-D color shaded terrain. The models are automatically updated every 15 minutes to provide the emergency response manager with a continuous display …
Date: January 28, 1993
Creator: Lawver, B. S.; Sullivan, T. J. & Baskett, R. L.
System: The UNT Digital Library
POLARIZED HYDROGEN JET TARGET FOR MEASUREMENT OF RHIC PROTON BEAM POLARIZATION. (open access)

POLARIZED HYDROGEN JET TARGET FOR MEASUREMENT OF RHIC PROTON BEAM POLARIZATION.

The performance and unique features of the RHIC polarized jet target and our solutions to the important design constraints imposed on the jet by the RHIC environment are described. The target polarization and thickness were measured to be 0.924 {+-} 2% and 1.3 {+-} 0.2 x 10{sup 12} atoms/cm{sup 2} respectively.
Date: January 28, 2005
Creator: Makdisi, Y.; Wise, T.; Chapman, M.; Graham, D.; Kponou, A.; Mahler, G. et al.
System: The UNT Digital Library
Flor-Essence? Herbal Tonic Promotes Mammary Tumor Development in Sprague Dawley Rats (open access)

Flor-Essence? Herbal Tonic Promotes Mammary Tumor Development in Sprague Dawley Rats

Background: Women who are diagnosed with breast cancer often self-administer complementary and alternative medicines to augment their conventional treatments, improve health, or prevent recurrence. Flor-Essence{reg_sign} Tonic is a complex mixture of herbal extracts used by cancer patients because of anecdotal evidence that it can treat or prevent disease. Methods: Female Sprague Dawley rats were given water or exposed to 3% or 6% Flor-Essence{reg_sign} beginning at one day of age. Mammary tumors were induced with a single oral 40 mg/kg/bw dose of dimethylbenz(a)anthracene at 50 days of age and sacrificed at 23 weeks. Rats were maintained on AIN-76A diet. Results: Control rats had palpable mammary tumor incidence of 51.0% at 19 weeks of age compared to 65.0% and 59.4% for the 3% and 6% Flor-Essence{reg_sign} groups respectively. Overall, no significant difference in time until first palpable tumor was detected among any of the groups. At necropsy, mammary tumor incidence was 82.5% for controls compared to 90.0% and 97.3% for rats consuming 3% and 6% Flor-Essence{reg_sign}, respectively. Mean mammary tumor multiplicity ({+-}SES) for the controls was 2.8 ({+-} 0.5) and statistically different from the 3% or 6% Flor- Essence{reg_sign} groups with 5.2 ({+-} 0.7), and 4.8 ({+-} 0.6), respectively (p{<=}0.01). As expected, …
Date: January 28, 2004
Creator: Bennett, L; Montgomery, J; Steinberg, S & Kulp, K
System: The UNT Digital Library
Using Independent Component Analysis to Separate Signals in Climate Data (open access)

Using Independent Component Analysis to Separate Signals in Climate Data

Global temperature series have contributions from different sources, such as volcanic eruptions and El Nino Southern Oscillation variations. We investigate independent component analysis as a technique to separate unrelated sources present in such series. We first use artificial data, with known independent components, to study the conditions under which ICA can separate the individual sources. We then illustrate the method with climate data from the National Centers for Environmental Prediction.
Date: January 28, 2003
Creator: Fodor, I K & Kamath, C
System: The UNT Digital Library
Water at a hydrophilic solid surface probed by ab-initio molecular dynamics: inhomogeneous thin layers of dense fluid (open access)

Water at a hydrophilic solid surface probed by ab-initio molecular dynamics: inhomogeneous thin layers of dense fluid

We present a microscopic model of the interface between liquid water and a hydrophilic, solid surface, as obtained from ab-initio molecular dynamics simulations. In particular, we focused on the (100)surface of cubic SiC, a leading candidate semiconductor for bio-compatible devices. Our results show that, in the liquid in contact with the clean substrate, molecular dissociation occurs in a manner unexpectedly similar to that observed in the gas phase. After full hydroxylation takes place, the formation of a thin ({approx}3 {angstrom})interfacial layer is observed, which has higher density than bulk water and forms stable hydrogen bonds with the substrate. The liquid does not uniformly wet the surface, rather molecules preferably bind along directions parallel to the Si dimer rows. Our calculations also predict that one dimensional confinement between two hydrophilic surfaces at about 1.3 nm distance does not affect the structural and electronic properties of the whole water sample.
Date: January 28, 2005
Creator: Cicero, G; Grossman, J; Galli, G & Catellani, A
System: The UNT Digital Library
Neutron Skyshine Considerations For The NIF Shielding Design (open access)

Neutron Skyshine Considerations For The NIF Shielding Design

A series of coupled neutron-photon transport Monte-Carlo calculations was performed to estimate the roof shielding required to limit the skyshine dose to less than 1 mrem/y at the site boundary when conducting DT experiments with annual fusion yields up to 1200 MJ (4.2E20 neutrons/y). The NIF shielding design consists of many different components. The basic components include 10-cm-thick Al chamber with 40-cm-thick target chamber gunite shield having multiple penetrations, 1.83-m-thick concrete Target Bay walls, 1.37-m-thick concrete roof, and multiple concrete floors with numerous penetrations. Under this shielding configuration, the skyshine dose at the nearest site-boundary was calculated to be less than 0.2 mrem/y for all possible target illumination configurations. The potential dose at the site boundary would be about one-tenth of the cosmic neutron dose that we measured with bubble neutron detectors on board a commercial roundtrip flight from SF to Rochester. This incremental dose increase is well within the normal fluctuations (noise) of the natural background radiation in the Livermore area. The skyshine dose has no impact on the public. The skyshine dose trends at ground and elevated levels are plotted as a function of distance from 20 m to 1000 m from the center of the target bay. …
Date: January 28, 2004
Creator: Singh, M S; Mecozzi, J M & Tobin, M T
System: The UNT Digital Library
Measurement of the Analyzing Power in PP Elastic Scattering in the Peak CNI Region at RHIC (open access)

Measurement of the Analyzing Power in PP Elastic Scattering in the Peak CNI Region at RHIC

The analyzing power A{sub N} for pp elastic scattering is expected to reach a peak value of 0.045 in the Coulomb Nuclear Interference (CNI) region at a momentum transfer -t of 0.003 (GeV/c){sup 2}. During the 2004 RHIC Run, we completed a measurement of A{sub N} in the CNI region by detecting the recoil protons from pp elastic scattering using a polarized atomic hydrogen gas jet target and the 100 GeV RHIC proton beam. We report the first measurements of the A{sub N} absolute value and shape in the -t range from 0.0015 to 0.010 (GeV/c){sup 2} with a precision better than 0.005 for each A{sub N} data point. The recoil protons were detected with two arrays of Si detectors. The absolute target polarization as monitored by a Breit-Rabi polarimeter was stable at 0.924 {+-} 0.018. This result allows us to further investigate the spin dependence of elastic pp scattering in the very low -t region.
Date: January 28, 2005
Creator: Makdisi, Y.; Okada, H.; Alekseev, I. G.; Bravar, A.; Bunce, G. & AL, ET
System: The UNT Digital Library
A high-order finite-volume method for hyperbolic conservation laws on locally-refined grids (open access)

A high-order finite-volume method for hyperbolic conservation laws on locally-refined grids

We present a fourth-order accurate finite-volume method for solving time-dependent hyperbolic systems of conservation laws on Cartesian grids with multiple levels of refinement. The underlying method is a generalization of that in [5] to nonlinear systems, and is based on using fourth-order accurate quadratures for computing fluxes on faces, combined with fourth-order accurate Runge?Kutta discretization in time. To interpolate boundary conditions at refinement boundaries, we interpolate in time in a manner consistent with the individual stages of the Runge-Kutta method, and interpolate in space by solving a least-squares problem over a neighborhood of each target cell for the coefficients of a cubic polynomial. The method also uses a variation on the extremum-preserving limiter in [8], as well as slope flattening and a fourth-order accurate artificial viscosity for strong shocks. We show that the resulting method is fourth-order accurate for smooth solutions, and is robust in the presence of complex combinations of shocks and smooth flows.
Date: January 28, 2011
Creator: McCorquodale, Peter & Colella, Phillip
System: The UNT Digital Library
Identifying the Sources of Nitrate to a Deep Municipal Water Supply Well Using Stable Isotopes of Nitrate, Groundwater Age Dating, and Depth-Specific Sampling (open access)

Identifying the Sources of Nitrate to a Deep Municipal Water Supply Well Using Stable Isotopes of Nitrate, Groundwater Age Dating, and Depth-Specific Sampling

None
Date: January 28, 2011
Creator: Singleton, M J; Gailey, R M; Moran, J E; Sutton, M C; Heller, N; Esser, B K et al.
System: The UNT Digital Library
Traverse Focusing of Intense Charged Particle Beams with Chromatic Effects for Heavy Ion Fusion (open access)

Traverse Focusing of Intense Charged Particle Beams with Chromatic Effects for Heavy Ion Fusion

A fi nal focusing scheme designed to minimize chromatic effects is discussed. The Neutralized Drift Compression Experiment-II (NDCX-II) will apply a velocity tilt for longitudinal bunch compression, and a fi nal focusing solenoid (FFS) for transverse bunch compression. In the beam frame, neutralized drift compression causes a suffi#14;ciently large spread in axial momentum, pz , resulting in chromatic effects to the fi nal focal spot during transverse bunch compression. Placing a weaker solenoid upstream of a stronger fi nal focusing solenoid (FFS) mitigates chromatic effects and improves transverse focusing by a factor of approximately 2-4 for appropriate NDCX-II parameters.
Date: January 28, 2013
Creator: James M. Mitrani, Igor D. Kaganovich, Ronald C. Davidson
System: The UNT Digital Library
Grain boundary concentration mapping by the CoRaD technique. [Cu--0. 074 to 1. 82 percent U; Count Rate Discriminator (CoRaD)] (open access)

Grain boundary concentration mapping by the CoRaD technique. [Cu--0. 074 to 1. 82 percent U; Count Rate Discriminator (CoRaD)]

Copper and uranium were melted together in an electron beam furnace, rolled and vacuum annealed at 900/sup 0/C. Several samples were examined, varying in uranium content from 0.074 to 1.82 wt. percent. Each sample was mounted in a resin and polished for optical microscope and electron microprobe work. These samples, when viewed under an optical microscope exhibited three distinct phases: featureless grain surfaces, a light gray phase in the grain boundaries, and an occasional dark gray phase also found in the grain boundaries. It is shown that the Count Rate Discriminator technique used in coincidence with a target current detector provides a powerful tool to map and to determine quantitatively the distribution of minor phases in grain boundaries and inclusions. (DLC)
Date: January 28, 1977
Creator: Meisenheimer, R. G. & McCoy, D. D.
System: The UNT Digital Library