Serial/Series Title
Fiscal Year 2001
7
Small Wind Electric Systems Consumers' Guides
6
Fiscal Year 2007
4
Proceedings of RIKEN BNL Research Center Workshop
4
ARM Facilities Newsletter
3
Effective Conveyor Belt Inspection for Improved Mining Productivity Progress Report
3
Fiscal Year 2000
3
Fiscal Year 2004
3
Gas/Liquid Membranes for Natural Gas Upgrading Quarterly Report
3
High Resolution Prediction of Gas Injection Process Performance for Heterogeneous Reservoirs Quarterly Report
3
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Performance Evaluations of Prototype Houses: Minimum 40% Residential Building Energy Savings Level Habitat for Humanity of Greater Newburgh Liberty Street Project: April 2003--September 2004
Habitat for Humanity International (HfHI) is a nonprofit organization that engages volunteers and would-be homebuyers in programs that emphasize sweat-equity and self-help. Habitat is among the top-ten housing producers in the United States. In collaboration with the HfHI Department of Construction & Environmental Resources, Steven Winter Associates, Inc., (SWA) began working with the Habitat for Humanity of Greater Newburgh (HfHGN) affiliate in Newburgh, New York, in April 2003. Since October 1999, HfHGN has acquired and renovated abandoned houses for an average cost of $45,000 per home. The affiliate serves area families living in overcrowded, substandard housing and spending 50% to 80% of their income on housing. In August 2003, HfHGN began their first new construction project, six row houses located on Liberty Street in Newburgh.
Date:
June 1, 2005
Creator:
Guilbert, R. & Magee, A.
Object Type:
Report
System:
The UNT Digital Library
Paradyn a parallel nonlinear, explicit, three-dimensional finite-element code for solid and structural mechanics user manual
ParaDyn is a parallel version of the DYNA3D computer program, a three-dimensional explicit finite-element program for analyzing the dynamic response of solids and structures. The ParaDyn program has been used as a production tool for over three years for analyzing problems which range in size from a few tens of thousands of elements to between one-million and ten-million elements. ParaDyn runs on parallel computers provided by the Department of Energy Accelerated Strategic Computing Initiative (ASCI) and the Department of Defense High Performance Computing and Modernization Program. Preprocessing and post-processing software utilities and tools are designed to facilitate the generation of partitioned domains for processors on a massively parallel computer and the visualization of both resultant data and boundary data generated in a parallel simulation. This manual provides a brief overview of the parallel implementation; describes techniques for running the ParaDyn program, tools and utilities; and provides examples of parallel simulations.
Date:
June 1, 2000
Creator:
Hoover, C G; DeGroot, A J & Sherwood, R J
Object Type:
Report
System:
The UNT Digital Library
Predicting Human Thermal Comfort in Automobiles
The objects of this report are to: (1) increase national energy security by reducing fuel use for vehicle climate control systems; (2) show/demonstrate technology that can reduce the fuel used by LD vehicles' ancillary systems; and (3) develop tools to evaluate the effectiveness of energy-efficient systems including--comfort, cost, practicality, ease-of-use, and reliability.
Date:
June 1, 2005
Creator:
Rugh, J.; Bharathan, D. & Chaney, L.
Object Type:
Presentation
System:
The UNT Digital Library
Measurement of Ultra Low Outgassing Rates for NLC UHV Vacuum Chambers
Ultra low outgassing rates would be highly advantageous in accelerators and storage rings, such as the Next Linear Collider (NLC), where an outgassing rate of <10{sup -12} Torr liter/sec/cm{sup 2} could eliminate the need for costly distributed pumping. Measuring such low outgassing rates at room temperature has many difficulties. However, by inspection of Fick's law, it can be seen that thermal desorption is proportional to outgassing rate. It is commonly observed that the outgas rate doubles approximately every 15 C for temperatures under 100 C. By measuring outgassing rate versus temperature and time and extrapolating back to room temperature we can measure outgassing rates that would otherwise be difficult to make. To produce a reliable measurement also requires the total surface area under study to be approximately an order of magnitude greater than the area of the measurement chamber walls. To accomplish this, 27 plates of 5083 aluminum were placed in the measurement chamber. This technique will be the basis for future investigation of outgassing rates of other sample plates fabricated with different machining and cleaning techniques.
Date:
June 12, 2001
Creator:
Kishiyama, K.; Shen, S.; Behne, D.; Corlett, J. N.; Atkinson, D.; Kennedy, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Relative x-ray backlighter intensity comparison of ti and ti/sc combination foils driven in double-sided and single-sided laser configuration
Use of multiple backlighter foils and/or double-sided laser interaction geometry with backlit imaging can result in improved backlighter efficiency. An experimental comparison of backlighter intensity for Ti foils and Ti/Sc combination foils in both the one-sided and double-sided laser-interaction configuration is presented. Spectrally-integrated framing camera images show intensity contributions of front and rear backlighter surfaces for both foil types. Analysis of time-resolved x-ray spectra collected from foil targets show the relative contribution of Ti and Sc 2-1 He-like resonance lines to the total backlighter intensity.
Date:
June 5, 2000
Creator:
Bullock, A. B.; Landen, O. L. & Bradley, D. K.
Object Type:
Article
System:
The UNT Digital Library
Simulating Electron Cloud Effects in Heavy-Ion Beams
None
Date:
June 4, 2004
Creator:
Cohen, R; Friedman, A; Lund, S; Molvik, A; Azevedo, T; Vay, J et al.
Object Type:
Article
System:
The UNT Digital Library
What is a Shock Wave to an Explosive Molecule?
An explosive molecule is a metastable chemical species that reacts exothermically given the correct stimulus. Impacting an explosive with a shock wave is a ''wake-up call'' or ''trigger'' which compresses and heats the molecule. The energy deposited by the shock wave must be distributed to the vibrational modes of the explosive molecule before chemical reaction can occur. If the shock pressure and temperature are high enough and last long enough, exothermic chemical decomposition can lead to the formation of a detonation wave. For gaseous, liquid, and perfect single crystal solid explosives, after an induction time, chemical reaction begins at or near the rear boundary of the charge. This induction time can be calculated by high pressure, high temperature transition state theory. A ''superdetonation'' wave travels through the preshocked explosive until it overtakes the initial shock wave and then slows to the steady state Chapman-Jouguet (C-J) velocity. In heterogeneous solid explosives, initiation of reaction occurs at ''hot spots'' created by shock compression. If there is a sufficient number of large and hot enough ''hot spots,'' these ignition sites grow creating a pressure pulse that overtakes the leading shock front causing detonation. Since the chemical energy is released well behind the leading …
Date:
June 12, 2001
Creator:
Tarver, Craig M.
Object Type:
Article
System:
The UNT Digital Library
Fs Laser Fabrication of Photonic Structures in Glass: the Role of Glass Composition
The use of fs lasers to directly write photonic structures inside a glass has great potential as a fabrication method for three-dimensional all-optical integrated components. The ability to use this technique with different glass compositions--specifically tailored for a specific photonics application--is critical to its successful exploitation. Consequently, it is important to understand how glass composition effects waveguide fabrication with fs laser pulses and how different glasses are structurally modified after exposure to fs laser pulses. We have used confocal laser spectroscopy to monitor the changes in glass structure that are associated with waveguide fabrication. Using a low power continuous wave (cw) Ar laser as excitation source we have measured both Raman and fluorescence spectra of the modified regions. Raman spectroscopy provides us with information on the network structure, whereas fluorescence measurements reveal the presence of optically active point defects in the glass. In this paper we review our work on fs-laser fabrication and characterization of photonic structures in glass and discuss the effect of glass composition on processing parameters and structural modification.
Date:
June 16, 2004
Creator:
Krol, D M; Chan, J W; Huser, T R; Risbud, S H & Hayden, J S
Object Type:
Article
System:
The UNT Digital Library
Insulated Pressure Vessels for Vehicular Hydrogen Storage: Analysis and Performance Evaluation
Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The work described here is directed at verifying that commercially available pressure vessels can be safely used to store liquid hydrogen. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Required future tests are described that will prove that no technical barriers exist to the safe use of aluminum-fiber vessels at cryogenic temperatures. Future activities also include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for obtaining certification for insulated pressure vessels.
Date:
June 26, 2001
Creator:
Aceves, S. M.; Martinez-Frias, J.; Garcia-Villazana, O. & Espinosa-Loza, F.
Object Type:
Article
System:
The UNT Digital Library
A Search for supersymmetric Higgs bosons in the di-tau decay mode in p anti-p collisions at s**(1/2) = 1.8-TeV
A search for direct production of Higgs bosons in the di-tau decay mode is performed with 86.3 {+-} 3.5 pb{sup -1} of data collected with the Collider Detector at Fermilab during the 1994-1995 data taking period of the Tevatron. We search for events where one tau decays to an electron plus neutrinos and the other tau decays hadronically. We perform a counting experiment and set limits on the cross section for supersymmetric Higgs boson production where tan {beta} is large and m{sub A} is small. For a benchmark parameter space point where m{sub A{sup 0}} = 100 GeV/c{sup 2} and tan {beta} = 50, we limit the production cross section multiplied by the branching ratio to be less than 77.9 pb at the 95% confidence level compared to theoretically predicted value of 11.0 pb. This is the first search for Higgs bosons decaying to tau pairs at a hadron collider.
Date:
June 1, 2005
Creator:
Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Internal Voltage in a Conducting Closed Hollow Cylinder With an Attached End Plate Subjected to a Direct Lightning Strike
The interior voltage of a large metal can with thick walls struck directly by lightning was estimated using diffusion theory, aperture slot voltage theory, and experimental data. The hollow cylinder is closed at both ends. One end has a cap that is welded to the cylinder wall making a continuous electrical interface. The other end consists of a circular plate that is pressed into the cylinder wall and held under pressure with a threaded ring. From our experience with coupling measurements, this joint will be a weak link. It will allow more current to leak into the interior than from diffusion through the walls. Because the joint was designed for mechanical purposes, the electrical properties, such as continuity around the circumference, are not well controlled. Therefore, it is difficult to determine a single voltage attributed to this joint design with varying electrical characteristics. Instead, we will make a best effort of bounding the problem using both analytical calculations and data from tests of similar structures. The calculated internal cylinder voltage subjected to an extreme lightning strike from current diffusing through the wall is 19 volts. We estimate that the press-fit end plate will increase this voltage by a factor of …
Date:
June 1, 2000
Creator:
Ong, M. M. & Anderson, R. A.
Object Type:
Report
System:
The UNT Digital Library
Generation of Electric and Magnetic Fields During Detonation of High Explosive Charges in Boreholes
We present experimental results of a study of electromagnetic field generation during underground detonation of high explosive charges in holes bored in sandy loam and granite. Test conditions and physico-mechanical properties of the soil exert significant influence on the parameters of electromagnetic signals generated by underground TNT charges with masses of 2 - 200 kg. The electric and magnetic field experimental data are satisfactorily described by an electric dipole model with the source embedded in a layered media.
Date:
June 4, 2004
Creator:
Soloviev, S. & Sweeney, J.
Object Type:
Article
System:
The UNT Digital Library
Acoustic Propagation in a Water-Filled Cylindrical Pipe
This study was concerned with the physics of the propagation of a tone burst of high frequency sound in a steel water-filled pipe. The choice of the pulse was rather arbitrary, so that this work in no way can be considered as recommending a particular pulse form. However, the MATLAB computer codes developed in this study are general enough to carry out studies of pulses of various forms. Also, it should be pointed out that the codes as written are quite time consuming. A computation of the complete field, including all 5995 modes, requires several hours on a desktop computer. The time required by such computations as these is a direct consequence of the bandwidths, frequencies and sample rates employed. No attempt was made to optimize these codes, and it is assumed that much can be done in this regard.
Date:
June 1, 2003
Creator:
Sullivan, E. J. & Candy, J. V.
Object Type:
Report
System:
The UNT Digital Library
Evacuated-Tube Heat-Pipe Solar Collectors Applied to the Recirculation Loop in a Federal Building: Preprint
This paper describes the design, simulation, construction, and initial performance of a solar water heating system (a 360-tube evacuated-tube heat-pipe solar collector, 54 m2 in gross area, 36 m2 in net absorber area) installed at the top of the hot water recirculation loop in the Social Security Administration's Mid-Atlantic Center in Philadelphia. When solar energy is available, water returning to the hot water storage tank is heated by the solar array. This new approach, in contrast to the more conventional approach of preheating incoming water, is made possible by the thermal diode effect of heat pipes and low heat loss from evacuated-tube solar collectors. The simplicity of this approach and its low installation costs support the deployment of solar energy in existing commercial buildings, especially where the roof is some distance away from the water heating system, which is often in the basement. Initial performance measurements of the system are reported.
Date:
June 1, 2004
Creator:
Walker, A.; Mahjouri, F. & Stiteler, R.
Object Type:
Article
System:
The UNT Digital Library
Terascale simulations for heavy ion inertial fusion energy
The intense ion beams in a heavy ion Inertial Fusion Energy (IFE) driver and fusion chamber are non-neutral plasmas whose dynamics are largely dominated by space charge. We propose to develop a ''source-to-target'' Heavy Ion Fusion (HIF) beam simulation capability: a description of the kinetic behavior of this complex, nonlinear system which is both integrated and detailed. We will apply this new capability to further our understanding of key scientific issues in the physics of ion beams for IFE. The simulations will entail self-consistent field descriptions that require interprocessor communication, but are scalable and will run efficiently on terascale architectures. This new capability will be based on the integration of three types of simulations, each requiring terascale computing: (1) simulations of acceleration and confinement of the space-charge-dominated ion beams through the driver (accelerator, pulse compression line, and final focusing system) which accurately describe their dynamics, including emittance growth (phase-space dilution) effects; these are particle-in-cell (PIC) models; (2) electromagnetic (EM) and magnetoinductive (Darwin) simulations which describe the beam and the fusion chamber environment, including multibeam, neutralization, stripping, beam and plasma ionization processes, and return current effects; and (3) highly detailed simulations (6f, multispecies PIC, continuum Vlasov), which can examine electron effects …
Date:
June 8, 2000
Creator:
Friedman, A.; Cohen, R. H.; Grote, D. P.; Sharp, W. M.; Celata, C. M.; Lee, E. P. et al.
Object Type:
Report
System:
The UNT Digital Library
Data Transport in a Novel Wireless Sensor Network
The deployment and operation of large wireless sensor networks can pose difficult problems, particularly in time critical situations, over large geographic areas, or in rugged terrain. An approach to this problem is to use unmanned air vehicles to first deploy the sensors, and then provide communication services to the sensors. This paper presents a network model that describes the flow of data through such a sensor network. Simulation results are presented that illustrate the behavior of the data flow in steady state and transient conditions.
Date:
June 1, 2001
Creator:
Roberts, R S
Object Type:
Article
System:
The UNT Digital Library
Hydrodynamic Modeling of a Multi-Pulse X-Ray Converter Target for DARHT - II
In phase two of the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT-II), four electron beam pulses of variable pulse length strike an X-ray converter target to produce time-resolved X-ray image. An important requirement for the converter target is to minimize the hydrodynamic expansion of the converter material so that there is enough material to generate the required X-ray dose for all four pulses. Minimizing the hydrodynamic expansion is also important from the standpoint of beam transport. If there is too much expansion of the converter material, the spot-size of the beam will deteriorate due to the charge neutralization of the beam by the target plasma. The beam spot size can also be deteriorated by backstreaming ions. However, this effect can be minimized by placing a barrier foil in front of the target. In this paper, we present a converter target design, based on the simulations using the radiation hydrodynamics code LASNEX and the Monte Carlo radiation transport code MCNP, that can produce the required X-ray dose for all four pulses with tolerable X-ray spot size variation. Our calculations also show that the barrier foil may block the backstreaming ions for all four pulses.
Date:
June 28, 2001
Creator:
Ho, D. D. M.; Chen, Y. J.; Harte, J. & Young, D.
Object Type:
Article
System:
The UNT Digital Library
Mechanical properties of D0 Run IIB silicon detector staves
A proposed stave design for the D0 Run IIb silicon tracker outer layers featuring central cooling channels and a composite shell mechanical structure is evaluated for self-deflection and deflection due to external loads. This paper contains an introduction to the stave structure, a section devoted to composite lamina and laminate properties and finally a section discussing the beam deflections expected for assembled staves using these laminates.
Date:
June 14, 2001
Creator:
Lanfranco, Giobatta & Fast, James
Object Type:
Report
System:
The UNT Digital Library
Simulation of Detonation Problems with MLS Grid Free Methodology
The MLS grid free rezone method, a simple, flexible finite difference method to solve general mechanics problems, especially detonation problems, is proposed in this paper. The spatial points that carry time dependent data are distributed in space in such a way that provides nearly uniform spacing of points, accurate presentation of boundaries, easy variation of resolutions and arbitrary deletion of irrelevant regions. Local finite difference operators are obtained with simple MLS differentiation. There is no specific topological or geometrical restriction with the distribution of data points. Therefore this method avoids many drawbacks of the traditional CFD methods. Because of its flexibility, it can be used to simulate a wide range of mechanics problems. Because of its simplicity, it has the potential to become a preferred method. Most traditional CFD methods, from a SPH view, can be considered as special cases of grid free methods of specific kernel functions. Such a generalization allows the development of a unified grid free CFD code that can be switched to various CFD methods by switching the kernel functions. Because of the flexibility in management and simplicity of coding, such a unified code is desired.
Date:
June 5, 2002
Creator:
Yao, J; Gunger, M E & Matuska, D A
Object Type:
Article
System:
The UNT Digital Library
Lawrence Livermore National Laboratory Measurements of Plutonium-bearing Oxide in DOE-STD-3013-2000 Containers Using Calorimetry and Gamma Isotopic Analyses
Lawrence Livermore National Laboratory (LLNL) routinely uses calorimetry and gamma isotopic analyses (Cal/Iso) for the accountability measurement of plutonium (Pu) bearing items. In the past 15 years, the vast majority of those items measured by Cal/Iso were contained in a thin-walled convenience can enclosed in another thin-walled outer container. However, LLNL has recently begun to use DOE-STD-3013-2000 containers as well. These DOE-STD-3013-2000 containers are comprised of a stainless steel convenience can enclosed in welded stainless steel primary and secondary containers. In addition to the fact that the wall thickness of the DOE-STD-3013-2000 containers is much greater than that of other containers in our experience, the DOE-STD-3013-2000 containers appear to have larger thermal insulation characteristics. To date, we have derived Pu-mass values from Cal/Iso measurements of 74 different DOE-STD-3013-2000 containers filled with Pu-bearing oxide or mixed uranium-plutonium (U-Pu) oxide material. Both water-bath and air-bath calorimeters were used for these measurements and both use software to predict when thermal equilibrium is attained. Our experience has shown that after apparent equilibrium has been attained, at least one more complete cycle, and sometimes two or three more complete cycles, is required to gain a measure of true thermal equilibrium. Otherwise, the derived Pu-mass values …
Date:
June 23, 2004
Creator:
Dearborn, D M & Keeton, S C
Object Type:
Article
System:
The UNT Digital Library
Photovoltaic Module Thermal/Wind Performance: Long-Term Monitoring and Model Development for Energy Rating
In order to predict the energy production of photovoltaic (PV) modules, it is necessary to predict the module temperature as a function of ambient temperature, wind speed, wind direction, total irradiance, and relative humidity. This paper presents a mathematical model to predict the module temperature based on the field monitored real data of module temperature, ambient temperature, wind speed, wind direction and relative humidity.
Date:
June 1, 2003
Creator:
TamizhMani, G.; Ji, L.; Tang, Y.; Petacci, L. & Osterwald, C.
Object Type:
Article
System:
The UNT Digital Library
Investigate Methods to Decrease Compilation Time-AX-Program Code Group Computer Science R& D Project
Large simulation codes can take on the order of hours to compile from scratch. In Kull, which uses generic programming techniques, a significant portion of the time is spent generating and compiling template instantiations. I would like to investigate methods that would decrease the overall compilation time for large codes. These would be methods which could then be applied, hopefully, as standard practice to any large code. Success is measured by the overall decrease in wall clock time a developer spends waiting for an executable. Analyzing the make system of a slow to build project can benefit all developers on the project. Taking the time to analyze the number of processors used over the life of the build and restructuring the system to maximize the parallelization can significantly reduce build times. Distributing the build across multiple machines with the same configuration can increase the number of available processors for building and can help evenly balance the load. Becoming familiar with compiler options can have its benefits as well. The time improvements of the sum can be significant. Initial compilation time for Kull on OSF1 was {approx} 3 hours. Final time on OSF1 after completion is 16 minutes. Initial compilation time …
Date:
June 11, 2003
Creator:
Cottom, T
Object Type:
Report
System:
The UNT Digital Library
Status of The General Atomics Low Speed Urban Maglev Technology Development Program
This paper presents the status of General Atomics Urban Maglev Program. The development provides an innovative approach for low speed transportation suitable for very challenging urban environments. Permanent magnets arranged in a 'Halbach' array configuration produce a relatively stiff magnetic suspension operating with an air gap of 25 mm. The project has progressed from design and prototype hardware testing, to the construction of a 120-meter full-scale test track, located in San Diego, California. Dynamic testing of the levitation, propulsion and guidance systems is being performed.
Date:
June 16, 2004
Creator:
Gurol, S; Baldi, R; Bever, D & Post, R
Object Type:
Article
System:
The UNT Digital Library
Hydrogen Peroxide Gas Generator Cycle with a Reciprocating Pump
A four-chamber piston pump is powered by decomposed 85% hydrogen peroxide. The performance envelope of the evolving 400 gram pump has been expanded to 172 cc/s water flow at discharge pressures near 5 MPa. A gas generator cycle system using the pump has been tested under similar conditions of pressure and flow. The powerhead gas is derived from a small fraction of the pumped hydrogen peroxide, and the system starts from tank pressures as low as 0.2 MPa. The effects of steam condensation on performance have been evaluated.
Date:
June 11, 2002
Creator:
Whitehead, J C
Object Type:
Article
System:
The UNT Digital Library