States

AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux (open access)

AMANDA Observations Constrain the Ultrahigh Energy Neutrino Flux

A number of experimental techniques are currently being deployed in an effort to make the first detection of ultra-high energy cosmic neutrinos. To accomplish this goal, techniques using radio and acoustic detectors are being developed, which are optimally designed for studying neutrinos with energies in the PeV-EeV range and above. Data from the AMANDA experiment, in contrast, has been used to place limits on the cosmic neutrino flux at less extreme energies (up to {approx}10 PeV). In this letter, we show that by adopting a different analysis strategy, optimized for much higher energy neutrinos, the same AMANDA data can be used to place a limit competitive with radio techniques at EeV energies. We also discuss the sensitivity of the IceCube experiment, in various stages of deployment, to ultra-high energy neutrinos.
Date: May 1, 2006
Creator: Halzen, Francis & Hooper, Dan
Object Type: Article
System: The UNT Digital Library
Amesos 1.0 reference guide. (open access)

Amesos 1.0 reference guide.

This document describes the main functionalities of the Amesos package, version 1.0. Amesos, available as part of Trilinos 4.0, provides an object-oriented interface to several serial and parallel sparse direct solvers libraries, for the solution of the linear systems of equations A X = B where A is a real sparse, distributed matrix, defined as an EpetraRowMatrix object, and X and B are defined as EpetraMultiVector objects. Amesos provides a common look-and-feel to several direct solvers, insulating the user from each package's details, such as matrix and vector formats, and data distribution.
Date: May 1, 2004
Creator: Sala, Marzio & Stanley, Ken D. (Oberlin, OH)
Object Type: Report
System: The UNT Digital Library
Amorphous and Thin-Film Silicon (open access)

Amorphous and Thin-Film Silicon

This paper outlines the key concepts set forth in the Amorphous and Thin-Film Silicon session at the National Center for Photovoltaics and Solar Program Review Meeting held March 26, 2003 in Denver, Colorado. Key elements of discussion centered around benchmarking the NREL/NCPV amorphous and thin-film silicon program, identifying holes in the scientific understanding of these materials and devices, identifying hurdles to large scale manufacturing, and what direction the program should take for future activities.
Date: May 1, 2003
Creator: Nelson, B. P.; Atwater, H. A.; von Roedern, B.; Yang, J.; Sims, P.; Deng, X. et al.
Object Type: Article
System: The UNT Digital Library

Amorphous Transparent Conducting Oxides (TCOs) Deposited at T 100<= ..deg.. C

The summary of this report is that amorphous InZnO (a-IZO) is a very versatile TCO with: (1) low process temperatures ({approx} 100 C); (2) easy to make by sputtering; (3) excellent optical and electronic properties; (4) very smooth etchable films; and (5) remarkable thermal processing stability.
Date: May 1, 2006
Creator: Perkins, J.; van Hest, M.; Teplin, C.; Alleman, J.; Dabney, M.; Gedvilas, L. et al.
Object Type: Presentation
System: The UNT Digital Library
ANALOG QUANTUM NEURON FOR FUNCTIONS APPROXIMATION (open access)

ANALOG QUANTUM NEURON FOR FUNCTIONS APPROXIMATION

We describe a system able to perform universal stochastic approximations of continuous multivariable functions in both neuron-like and quantum manner. The implementation of this model in the form of multi-barrier multiple-silt system has been earlier proposed. For the simplified waveguide variant of this model it is proved, that the system can approximate any continuous function of many variables. This theorem is also applied to the 2-input quantum neural model analogical to the schemes developed for quantum control.
Date: May 1, 2001
Creator: EZHOV, A.; KHROMOV, A. & BERMAN, G.
Object Type: Article
System: The UNT Digital Library
Analog signal pre-processing for the Fermilab Main Injector BPM upgrade (open access)

Analog signal pre-processing for the Fermilab Main Injector BPM upgrade

An analog signal pre-processing scheme was developed, in the framework of the Fermilab Main Injector Beam Position Monitor (BPM) Upgrade, to interface BPM pickup signals to the new digital receiver based read-out system. A key component is the 8-channel electronics module, which uses separate frequency selective gain stages to acquire 53 MHz bunched proton, and 2.5 MHz anti-proton signals. Related hardware includes a filter and combiner box to sum pickup electrode signals in the tunnel. A controller module allows local/remote control of gain settings and activation of gain stages, and supplies test signals. Theory of operation, system overview, and some design details are presented, as well as first beam measurements of the prototype hardware.
Date: May 1, 2006
Creator: Saewert, A. L.; Rapisarda, S. M. & Wendt, M.
Object Type: Article
System: The UNT Digital Library
Analyses of Wind Energy Impact on WFEC System Operations: Preprint (open access)

Analyses of Wind Energy Impact on WFEC System Operations: Preprint

Article for the Journal of Solar Energy Engineering which analyzes system and wind energy data recorded by WFEC and evaluates the effects of wind energy on system operations.
Date: May 1, 2006
Creator: Wan, Y. & Liao, J. R.
Object Type: Article
System: The UNT Digital Library
Analysis and Numerical Solution for Multi-Physics Coupling of Neutron Diffusion and Thermomechanics in Spherical Fast Burst Reactors (open access)

Analysis and Numerical Solution for Multi-Physics Coupling of Neutron Diffusion and Thermomechanics in Spherical Fast Burst Reactors

Coupling neutronics to thermomechanics is important for the analysis of fast burst reactors, because the criticality and safety study of fast burst reactors heavily depends on the thermomechanical behavior of fuel materials. For instance, the shut down mechanism or the transition between super and sub-critical states are driven by the fuel material expansion or contraction. The material expansion or contraction is due to temperature gradient which results from fission power. In this paper, we introduce a numerical model for coupling of neutron diffusion and thermomechanics in fast burst reactors. We also provide some analysis of the coupled system. We studied material behaviors corresponding to different levels of power pulses.
Date: May 1, 2009
Creator: Kadioglu, Samet Y.; Knoll, Dana A. & Oliveira, Cassiano de
Object Type: Article
System: The UNT Digital Library
Analysis of 2009 International Energy Conservation Code Requirements for Residential Buildings in Utah (open access)

Analysis of 2009 International Energy Conservation Code Requirements for Residential Buildings in Utah

The 2009 International Energy Conservation Code (IECC) contains several major improvements in energy efficiency over the current Utah code, the 2006 IECC. The most notable changes are improved duct sealing and efficient lighting requirements. A limited analysis of these changes resulted in estimated savings of $168 to $188 for an average new house in Utah at recent fuel prices.
Date: May 1, 2009
Creator: Cole, Pamala C. & Lucas, Robert G.
Object Type: Report
System: The UNT Digital Library
Analysis of a grid window structure for RF cavities in a Muon cooling channel (open access)

Analysis of a grid window structure for RF cavities in a Muon cooling channel

We report on the electromagnetic and thermal analysis of a grid window structure for high gradient, low frequency RF cavities. Windows may be utilized to close the beam iris and increase shunt impedance of closed-cell RF cavities. This work complements previous work presented for windows made of solid beryllium foil. An electromagnetic and thermal analysis of the thin wall tubes in a grid pattern was conducted using both MAFIA4 and ANSYS finite element analyses. The results from both codes agreed well for a variety of grid configurations and spacing. The grid configuration where the crossing tubes touched was found to have acceptable E-Fields and H-Fields performance. The thermal profiles for the grid will also be shown to determine a viable cooling profile.
Date: May 1, 2003
Creator: Ladran, A.; Li, D.; Moretti, A.; Rimmer, R.; Staples, J.; Virostek, S. et al.
Object Type: Article
System: The UNT Digital Library
Analysis of an Earthquake-Initiated-Transient in a PBR (open access)

Analysis of an Earthquake-Initiated-Transient in a PBR

One of the Design Basis Accidents (DBA) for a Pebble Bed Reactor has been identified as the “Safe shutdown earthquake with core conduction cooling to passive mode of Reactor Cavity Cooling System.” A new methodology to analyze this particular DBA has been developed at the Idaho National Laboratory (INL). During the seismic event the reactor core experiences the densification of the pebbles, which produce small reactivity insertions due to the effective fuel densification. In addition, a decrease in the active core height results in the relative withdrawal of the control rods, which are assumed to remain stationary during the transient. The methodology relies on the dynamic re-meshing of the core during the transient to capture the local packing fraction changes and their corresponding effects on temperature and reactivity. The core re-meshing methodology is based on the velocity profiles of the pebbles in the core, which were obtained with the INL’s pebble mechanics code PEBBLES. The methodology has been added to the coupled code system CYNOD-THERMIX-KONVEK. The reactor power calculation is further improved with the use of the new advanced TRISO fuel model to better approximate the temperatures in the fuel kernels. During the transient the core is brought back to …
Date: May 1, 2009
Creator: Ougouag, A. M.; Ortensi, J. & Hiruta, H.
Object Type: Article
System: The UNT Digital Library
Analysis of cavern stability at the West Hackberry SPR site. (open access)

Analysis of cavern stability at the West Hackberry SPR site.

This report presents computational analyses that simulate the structural response of caverns at the Strategic Petroleum Reserve (SPR) West Hackberry site. The cavern field comprises 22 caverns. Five caverns (6, 7, 8, 9, 11) were acquired from industry and have unusual shapes and a history dating back to 1946. The other 17 caverns (101-117) were leached according to SPR standards in the mid-1980s and have tall cylindrical shapes. The history of the caverns and their shapes are simulated in a three-dimensional geomechanics model of the site that predicts deformations, strains, and stresses. Future leaching scenarios corresponding to oil drawdowns using fresh water are also simulated by increasing the volume of the caverns. Cavern pressures are varied in the model to capture operational practices in the field. The results of the finite element model are interpreted to provide information on the current and future status of subsidence, well integrity, and cavern stability. The most significant results in this report are relevant to Cavern 6. The cavern is shaped like a bowl with a large ceiling span and is in close proximity to Cavern 9. The analyses predict tensile stresses at the edge of the ceiling during repressuization of Cavern 6 following …
Date: May 1, 2009
Creator: Ehgartner, Brian L. & Sobolik, Steven Ronald
Object Type: Report
System: The UNT Digital Library
Analysis of Contribution from Edge Radiation to Optical Diffraction Radiation (open access)

Analysis of Contribution from Edge Radiation to Optical Diffraction Radiation

Beam size measurement with near-field optical diffraction radiation (ODR) has been carried out successfully at CEBAF. The ODR station is installed on the Hall-A beam line after eight bending magnets. The ODR images were affected by an unexpected radiation. Some calculations for analyzing the source of the radiation will be presented. Furthermore, two schemes will be proposed to alleviate the contamination.
Date: May 1, 2009
Creator: C. Liu, P. Evtushenko, A. Freyberger, C. Liu, A.H. Lumpkin
Object Type: Article
System: The UNT Digital Library
ANALYSIS OF DATA FROM THE LEDA WIRE SCANNER/HALO SCRAPER (open access)

ANALYSIS OF DATA FROM THE LEDA WIRE SCANNER/HALO SCRAPER

A new diagnostic has been designed and commissioned that measures the profile of the beam in the halo channel of the Low Energy Demonstration Accelerator at the Los Alamos National Laboratory. This paper describes the algorithms written to analyze the data from that diagnostic, a combined wire scanner and halo scraper. These algorithms determine the safe insertions limit of the scrapers, spatially differentiate the scraper signal, amalgamate the wire scanner data with the differentiated scraper data, determine when both the core and combined distributions rise above the noise floor, and compute the moments of the combined distribution. Results of applying the algorithms to data acquired during experiments matching the beam into the halo channel are presented.
Date: May 1, 2001
Creator: KAMPERSCHROER, J.; O'HARA, J. & A, ET
Object Type: Article
System: The UNT Digital Library
Analysis of Depth-Sensing Indentation Tests with a Knoop Indenter (open access)

Analysis of Depth-Sensing Indentation Tests with a Knoop Indenter

The present work shows how data obtained in a depth-sensing indentation test using a Knoop indenter may be analyzed to provide elastic modulus and hardness of the specimen material. The method takes into account the elastic recovery along the direction of the short axis of the residual impression as the indenter is removed. If elastic recovery is not accounted for, the elastic modulus and hardness are overestimated by an amount that depends on the ratio of E/H of the specimen material. The new method of analysis expresses the elastic recovery of the short diagonal of the residual impression into an equivalent face angle for one side of the Knoop indenter. Conventional methods of analysis using this corrected angle provide results for modulus and hardness that are consistent with those obtained with other types of indenters.
Date: May 1, 2001
Creator: Riester, L
Object Type: Report
System: The UNT Digital Library
Analysis of emittance growth in the Fermilab Booster (open access)

Analysis of emittance growth in the Fermilab Booster

Multi-particle simulations are performed to study emittance growth in the Fermilab Booster. Analysis shows that the source of vertical emittance growth comes mostly from random errors in skew quadrupoles in the presence of a strong transverse space-charge force. [1] Random errors in dipole rolls and the Montague resonance do contribute but to lesser extent. The effect of random errors in the quadrupoles is small because the betatron envelope tunes are reasonably far away from the half-integer stopband.
Date: May 1, 2006
Creator: Ng, K. Y.; Huang, X. & Lee, S. Y.
Object Type: Article
System: The UNT Digital Library
Analysis of enhanced tan(beta) corrections in MFV GUT scenarios (open access)

Analysis of enhanced tan(beta) corrections in MFV GUT scenarios

Long-range forces between macroscopic objects are mediated by light particles that interact with the electrons or nucleons, and include spin-dependent static components as well as spin- and velocity-dependent components. We parametrize the long-range potential between two fermions assuming rotational invariance, and find 16 different components. Applying this result to electrically neutral objects, we show that the macroscopic potential depends on 72 measurable parameters. We then derive the potential induced by the exchange of a new gauge boson or spinless particle, and compare the limits set by measurements of macroscopic forces to the astrophysical limits on the couplings of these particles.
Date: May 1, 2006
Creator: Lunghi, Enrico; Porod, Werner & Vives, Oscar
Object Type: Article
System: The UNT Digital Library
Analysis of Hazards Associated with a Process Involving Uranium Metal and Uranium Hydride Powders (open access)

Analysis of Hazards Associated with a Process Involving Uranium Metal and Uranium Hydride Powders

An analysis of the reaction chemistry and operational factors associated with processing uranium and uranium hydride powders is presented, focusing on a specific operation in the Development Division which was subjected to the Job Hazard Analysis (JHA) process. Primary emphasis is on the thermodynamic factors leading to pyrophoricity in common atmospheres. The discussion covers feed powders, cold-pressed and hot-pressed materials, and stray material resulting from the operations. The sensitivity of the various forms of material to pyrophoricity in common atmospheres is discussed. Operational recommendations for performing the work described are given.
Date: May 1, 2000
Creator: Bullock, J.S.
Object Type: Report
System: The UNT Digital Library
Analysis of Low Energy AGS Polarimeter Data and Potential Consequences for RHIC Spin Physics (open access)

Analysis of Low Energy AGS Polarimeter Data and Potential Consequences for RHIC Spin Physics

N/A
Date: May 1, 2001
Creator: R., Cadman; Huang, H.; Krueger, K.; Spinka, H.; Underwood, D. & Yokosawa, A.
Object Type: Report
System: The UNT Digital Library
Analysis of Mesoscale Model Data for Wind Integration (Poster) (open access)

Analysis of Mesoscale Model Data for Wind Integration (Poster)

Supports examination of implications of national 20% wind vision, and provides input to integration and transmission studies for operational impact of large penetrations of wind on the grid.
Date: May 1, 2009
Creator: Schwartz, M.; Elliott, D.; Lew, D.; Corbus, D.; Scott, G.; Haymes, S. et al.
Object Type: Article
System: The UNT Digital Library
Analysis of Potential Benefits and Costs of Adopting ASHRAE Standard 90.1-1999 as a Commercial Building Energy Code in Illinois Jurisdictions (open access)

Analysis of Potential Benefits and Costs of Adopting ASHRAE Standard 90.1-1999 as a Commercial Building Energy Code in Illinois Jurisdictions

ASHRAE Standard 90.1-1999 was developed in an effort to set minimum requirements for energy efficienty design and construction of new commercial buildings. This report assesses the benefits and costs of adopting this standard as the building energy code in Illinois. Energy and economic impacts are estimated using BLAST combined with a Life-Cycle Cost approach to assess corresponding economic costs and benefits.
Date: May 1, 2002
Creator: Belzer, David B.; Cort, Katherine A.; Winiarski, David W.; Richman, Eric E. & Friedrich, Michele
Object Type: Report
System: The UNT Digital Library
Analysis of potential for jet-impingement erosion from leaking steam generator tubes during severe accidents. (open access)

Analysis of potential for jet-impingement erosion from leaking steam generator tubes during severe accidents.

This report summarizes analytical evaluation of crack-opening areas and leak rates of superheated steam through flaws in steam generator tubes and erosion of neighboring tubes due to jet impingement of superheated steam with entrained particles from core debris created during severe accidents. An analytical model for calculating crack-opening area as a function of time and temperature was validated with tests on tubes with machined flaws. A three-dimensional computational fluid dynamics code was used to calculate the jet velocity impinging on neighboring tubes as a function of tube spacing and crack-opening area. Erosion tests were conducted in a high-temperature, high-velocity erosion rig at the University of Cincinnati, using micrometer-sized nickel particles mixed in with high-temperature gas from a burner. The erosion results, together with analytical models, were used to estimate the erosive effects of superheated steam with entrained aerosols from the core during severe accidents.
Date: May 1, 2002
Creator: Majumdar, S.; Diercks, D. R.; Shack, W. J. & Technology, Energy
Object Type: Report
System: The UNT Digital Library
Analysis of salt and casing fracture mechanisms during cavern integrity testing for SPR salt caverns. (open access)

Analysis of salt and casing fracture mechanisms during cavern integrity testing for SPR salt caverns.

None
Date: May 1, 2006
Creator: Ehgartner, Brian L. & Sobolik, Steven Ronald
Object Type: Report
System: The UNT Digital Library
Analysis of sheltering and evacuation strategies for an urban nuclear detonation scenario. (open access)

Analysis of sheltering and evacuation strategies for an urban nuclear detonation scenario.

Development of an effective strategy for shelter and evacuation is among the most important planning tasks in preparation for response to a low yield, nuclear detonation in an urban area. This study examines shelter-evacuate policies and effectiveness focusing on a 10 kt scenario in Los Angeles. The goal is to provide technical insights that can support development of urban response plans. Results indicate that extended shelter-in-place can offer the most robust protection when high quality shelter exists. Where less effective shelter is available and the fallout radiation intensity level is high, informed evacuation at the appropriate time can substantially reduce the overall dose to personnel. However, uncertainties in the characteristics of the fallout region and in the exit route can make evacuation a risky strategy. Analyses indicate that only a relatively small fraction of the total urban population may experience significant dose reduction benefits from even a well-informed evacuation plan.
Date: May 1, 2009
Creator: Yoshimura, Ann S. & Brandt, Larry D.
Object Type: Report
System: The UNT Digital Library