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Variability in energy factor test results for residential electric water heaters (open access)

Variability in energy factor test results for residential electric water heaters

Recent modifications to the minimum energy efficiency requirements for residential water heaters have spurred an investigation into the variability in testing high-efficiency electric water heaters. While initial inter-laboratory comparisons showed excellent agreement between test results from different labs, subsequent inter-laboratory comparisons show differences between measured energy factors of up to 0.040. To determine the source of these differences, analyses of various parts of the test procedure are performed. For one case studied, the uncertainty in test results can be as high as +-0.028 if instrument accuracies reach the minimum level allowed in the test procedure. Other areas of the test procedure where variability is introduced are the optional use of pre-draws, the location of the lower tank temperature-measuring device, the use of insulation on tank fittings, and the use of a warm-up period before the simulated-use test commences. The implications of these issues on test results are provided.
Date: April 25, 2003
Creator: Healy, William; Lutz, James D. & Lekov, Alex
System: The UNT Digital Library
A standard interface for debugger access to message queue information in MPI. (open access)

A standard interface for debugger access to message queue information in MPI.

This paper discusses the design and implementation of an interface that allows a debugger to obtain the information necessary to display the contents of the MPI message queues. The design has been implemented in the TotalView debugger, and dynamic libraries that conform to the interface exist for MPICH, as well as the proprietary MPI implementations from Compaq, IBM, and SGI.
Date: June 25, 1999
Creator: Cownie, James & Gropp, William
System: The UNT Digital Library
[Article about Fred Harvey History] (open access)

[Article about Fred Harvey History]

Article written by Keith Hines about his memories and knowledge about the history of George Hill and Fred Harvey, as well as Harvey Houses and Harvey Girls.
Date: May 25, 1984
Creator: Hines, Keith
System: The Portal to Texas History
Grid-based methods for diatomic quantum scattering problems: a finite-element, discrete variable representation in prolate spheroidal coordinates (open access)

Grid-based methods for diatomic quantum scattering problems: a finite-element, discrete variable representation in prolate spheroidal coordinates

We show how to combine finite elements and the discrete variable representation in prolate spheroidal coordinates to develop a grid-based approach for quantum mechanical studies involving diatomic molecular targets. Prolate spheroidal coordinates are a natural choice for diatomic systems and have been used previously in a variety of bound-state applications. The use of exterior complex scaling in the present implementation allows for a transparently simple way of enforcing Coulomb boundary conditions and therefore straightforward application to electronic continuum problems. Illustrative examples involving the bound and continuum states of H2+, as well as the calculation of photoionization cross sections, show that the speed and accuracy of the present approach offer distinct advantages over methods based on single-center expansions.
Date: November 25, 2008
Creator: Tao, Liang; McCurdy, C. W. & Rescigno, T. N.
System: The UNT Digital Library
Mechanical design and fabrication processes for the ALS third-harmonic cavities (open access)

Mechanical design and fabrication processes for the ALS third-harmonic cavities

It is planned to install five third-harmonic (1.5 GHz) RF Cavities in May/June 1999 as an upgrade to the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL). This paper presents mechanical design features, their experiences in using electronic design models to expedite the manufacturing process, and the fabrication processes employed to produce these cavities for the ALS. They discuss some of the lessons learned from the PEP-II RF Cavity design and fabrication, and outline the improvements incorporated in the new design. They also report observations from the current effort.
Date: March 25, 1999
Creator: Franks, R. M.; Henderson, T.; Hernandez, K.; Otting, D.; Plate, D. & Rimmer, R. A.
System: The UNT Digital Library
Utilizing Computational Probabilistic Methods to Derive Shock Specifications in a Nondeterministic Environment (open access)

Utilizing Computational Probabilistic Methods to Derive Shock Specifications in a Nondeterministic Environment

One of the key elements of the Stochastic Finite Element Method, namely the polynomial chaos expansion, has been utilized in a nonlinear shock and vibration application. As a result, the computed response was expressed as a random process, which is an approximation to the true solution process, and can be thought of as a generalization to solutions given as statistics only. This approximation to the response process was then used to derive an analytically-based design specification for component shock response that guarantees a balanced level of marginal reliability. Hence, this analytically-based reference SRS might lead to an improvement over the somewhat ad hoc test-based reference in the sense that it will not exhibit regions of conservativeness. nor lead to overtesting of the design.
Date: October 25, 2000
Creator: Field Jr.,Richard V.; Red-Horse,John R. & Paez,Thomas L.
System: The UNT Digital Library
Status of Safety& Environmental Activities for Inertial Fusion Energy (open access)

Status of Safety& Environmental Activities for Inertial Fusion Energy

Over the past several years, significant progress has been made in the analysis of safety and environmental (S&E) issues for inertial fusion energy (IFE). Detailed safety assessments have been performed for the baseline power plant concepts, as well as for a conceptual target fabrication facility. Safety analysis results are helping to drive the agenda for experiments. A survey of the S&E characteristics--both radiological and chemical--of candidate target materials has been completed. Accident initiating events have been identified and incorporated into master logic diagrams, which will be essential to the detailed safety analyses that will be needed in the future. Studies of aerosol generation and transport will have important safety implications. A Monte Carlo-based uncertainty analysis procedure has been developed for use in neutron activation calculations. Finally, waste management issues are receiving increased attention and are deserving of further discussion.
Date: November 25, 2002
Creator: Latkowski, J. F.; Reyes, S.; Cadwallader, L. C.; Sharpe, J. P.; Marshall, T. D.; Merrill, B. J. et al.
System: The UNT Digital Library
A New Linear Inductive Voltage Adder Driver for the Saturn Accelerator (open access)

A New Linear Inductive Voltage Adder Driver for the Saturn Accelerator

None
Date: September 25, 2000
Creator: Mazarakis, Michael G.; Spielman, Rick B.; Struve, Kenneth W. & Long, Finis W.
System: The UNT Digital Library
Legacy material work-off project (open access)

Legacy material work-off project

Los Alamos National Laboratory (LANL) and its subcontractors recently completed a nine-month legacy material clean-up effort. Legacy materials were defined as chemicals, hazardous, non-hazardous, and both hazardous and radioactive (mixed), that no longer served a programmatic use and had no identified individual owner within the Laboratory. Once personnel identified the legacy materials, the items were transferred to Solid Waste Operation`s (EM-SWO) control. Upon completing this process, the responsible division-level manager was required to certify that all non-radioactive hazardous and non-hazardous materials and acceptable mixed legacy materials had been identified and transferred to EM-SWO for proper handling or disposal. The major expense in this project was the cost of actual chemical and radiological analysis. This expense was the result of items not having an identified individual owner. The major benefit of this project is that LANL is now in an excellent position to implement its Integrated Safety Management (ISM) Plan, which requires the implementation of safe work practices, including requirements for removing unused items when vacating workspaces. Effective implementation of ISM will go a long way toward ensuring that legacy materials are no longer an issue at the Laboratory.
Date: January 25, 1999
Creator: Sloan, Timothy J. & Baker, Don H., IV
System: The UNT Digital Library
Prediction of Frictional Pressure Drop During Water Permeation Through Packed Beds of Granular Particulates (open access)

Prediction of Frictional Pressure Drop During Water Permeation Through Packed Beds of Granular Particulates

A methodology has been developed based on the Kozeny-Carman equation to predict frictional pressure drops during water permeation of packed columns containing essentially noncompressible, but highly irregular particles. The resulting model accurately predicts pressure drop as a function of liquid flow rate and resin particle size for this system. A total of five particle sieve cuts across the range -20 to +70 mesh were utilized for testing using deionized water as the mobile phase. The Rosin-Rammler equation was used to fit the raw particle size data (wet sieve analysis) for the as-received resin sample and generate a continuous cumulative distribution function based on weight percent passing through the sieve. Probability distribution functions were calculated from the cumulative distribution for each particle sieve cut tested. Nine particle diameter definitions (i.e., number mean, volume mean, etc.) were then selected from the distribution function for each sample to represent the average spherically-equivalent particle diameter as input to the Kozeny-Carman equation. Nonlinear least squares optimization of the normalized pressure drop residuals were performed by parameter estimation of particle shape factor and bed porosity for all samples simultaneously using a given average particle diameter definition. Good fits to the full experimental data set were obtained …
Date: October 25, 2005
Creator: King, William D.; Aleman, Sebastian E.; Hamm, L. Larry & Pettis, Myra A.
System: The UNT Digital Library
Optical detection system for multispectral UV fluorescence laser remote sensing measurements (open access)

Optical detection system for multispectral UV fluorescence laser remote sensing measurements

A mobile laser remote sensing system is being developed for multispectral UV fluorescence detection of vapor, liquid, and solid effluents. TM system uses laser wavelengths between 250 and 400 nm to excite UV fluorescence spectra that can be used to detect and identify species in multicomponent chemical mixtures. With a scanning mirror assembly, the system is designed to map chemical concentrations with a range resolution of {approximately}5 m. In this paper we describe the optical detection system (scanning mirror assembly, 76 cm diameter collection telescope, relay optics, spectrometers, and detectors) associated data acquisition and control electronics. We also describe unique diagnostic software that is used for instrument setup and control.
Date: May 25, 1994
Creator: Tisone, G. C.; Clark, B.; Wakefield-Reyes, C.; Hargis, P. H., Jr.; Michie, B.; Downey, T. L. et al.
System: The UNT Digital Library
Carrier photodynamics in 2D perovskites with solution-processed silver and graphene contacts for bendable optoelectronics (open access)

Carrier photodynamics in 2D perovskites with solution-processed silver and graphene contacts for bendable optoelectronics

Article reporting on the inkjet printed, direct contact study of solution-processed, 2D perovskite-based photodetectors (PDs) formed on flexible PI substrates. Silver (Ag) and graphene (Gr) inks have been engineered to serve as efficient electrical contacts for solution-processed two-dimensional (2D) organo-halide (CH3(CH2)3NH3)2(CH3NH3)n−1PbnI3n+1 (n = 4) layered perovskites, where all inkjet-printed heterostructure PDs were fabricated on polyimide (PI) substrates.
Date: March 25, 2021
Creator: Hossain, Ridwan F.; Min, Misook; Ma, Liang-Chieh; Sakri, Shambhavi R. & Kaul, Anupama
System: The UNT Digital Library
Association of Home Food Availability with Prediabetes and Diabetes among Adults in the United States (open access)

Association of Home Food Availability with Prediabetes and Diabetes among Adults in the United States

This article examined associations of home food availabilities with prediabetes and diabetes among 8929 adults (20–70 years) participating in 2007–2010 National Health and Nutrition Examination Surveys. The results show prediabetes participants had lower availability of healthy foods and higher availability of unhealthy foods, suggesting the need to improve healthy food availability at home for this population.
Date: April 25, 2020
Creator: McAtee, Jenniffer; Tao, Meng-Hua; King, Christian & Chai, Weiwen
System: The UNT Digital Library
High-Throughput Computational Search for Half-Metallic Oxides (open access)

High-Throughput Computational Search for Half-Metallic Oxides

The article describes a high-throughput computational search for half-metallic compounds. The analysis of calculated electronic properties of thousands of materials from the inorganic crystal structure database allowed the authors to identify potential half metals. They found over two-hundred strong half-metallic oxides; several of them have never been reported before.
Date: April 25, 2020
Creator: Liyanage, Laalitha S. I.; Slawińska, Jagoda; Gopal, Priya; Curtarolo, Stefano; Fornari, Marco & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Longitudinal Monostatic Acoustic Effective Bulk Modulus and Effective Density Evaluation of Underground Soil Quality: A Numerical Approach (open access)

Longitudinal Monostatic Acoustic Effective Bulk Modulus and Effective Density Evaluation of Underground Soil Quality: A Numerical Approach

This article introduces a novel method using longitudinal sound to detect underground soil voids to inspect underwater bed property in terms of effective bulk modulus and effective density of the material properties.
Date: December 25, 2020
Creator: Jin, Yuqi; Choi, Tae-Youl & Neogi, Arup
System: The UNT Digital Library
2005 Atomic Physics Gordon Conference, June 26-July 1, 2005 (open access)

2005 Atomic Physics Gordon Conference, June 26-July 1, 2005

This article is a detailed description of the Gordon Research Conference on Atomic Physics.
Date: June 25, 2005
Creator: Monroe, Christopher
System: The UNT Digital Library
A new browser for the visualization of equation of state data (open access)

A new browser for the visualization of equation of state data

A prototype equation of state (EOS) browser application has been developed at LLNL. This browser provides an interactive, graphical user interface that allows EOS data to be analyzed, visualized, and compared with experimental data. The user can view our EOS table data in both tabular and graphical form, can obtain lists of table ranges, and can view material information. In addition, the browser allows the user to utilize the interpolation routines of our EOS package to produce the same interpolated EOS data that would be passed to a simulation code, and to analyze this data in many different ways. Interpolated data can be obtained through use of a query function, and lists of interpolated data over various ranges can be produced. Analysis functions include the calculation and display of isotherms, isochores, isobars, adiabats, and shock Hugoniots. Moreover, experimental data can be overlaid onto these plots in order to establish confidence in particular EOS tables. It is expected that this browser environment will be a valuable tool for scientists who use large simulation codes that access equation of state data.
Date: June 25, 1999
Creator: MacFarland, L. H. & Streletz, G.
System: The UNT Digital Library
An experiment to measure the electron neutrino mass using a cryogenic tritium source (open access)

An experiment to measure the electron neutrino mass using a cryogenic tritium source

An experiment has been performed to determine the electron neutrino mass with the precision of a few eV by measuring the tritium beta decay energy distribution near the endpoint. Key features of the experiment are a 2 eV resolution electrostatic spectrometer and a high-activity frozen tritium source. It is important that the source have electronic wavefunctions which can be accurately calculated. These calculations have been made for tritium and the HeT/sup +/ daughter ion and allow determination of branching fractions to 0.1% and energy of the excited states to 0.1 eV. The excited final molecular state calculations and the experimental apparatus are discussed. 4 refs., 5 figs.
Date: June 25, 1985
Creator: Fackler, O.; Jeziorski, B.; Kolos, W.; Monkhorst, H.; Mugge, M.; Sticker, H. et al.
System: The UNT Digital Library
Controlling our destinies: Historical, philosophical, social and ethical perspectives on the Human Genome Project: Final report, July 1, 1995-June 30, 1996 (open access)

Controlling our destinies: Historical, philosophical, social and ethical perspectives on the Human Genome Project: Final report, July 1, 1995-June 30, 1996

This report briefly describes the efforts by the organizing committee in preparation for the conference entitled Controlling Our Destinies: Historical, Philosophical, Social, and Ethical Perspectives on the Human Genome Project. The conference was held October 5-8, 1995.
Date: September 25, 1996
Creator: Sloan, P.R.
System: The UNT Digital Library
A Biocultural Dialogue between Thoreau and Taoist Thought: Rethinking Environmental Ethics, Nature, Spirituality and Place (open access)

A Biocultural Dialogue between Thoreau and Taoist Thought: Rethinking Environmental Ethics, Nature, Spirituality and Place

Article describes how a fundamental question of the 21st century centers around the role and place of humans in their environment. The authors assert that this paper aimed to discover and manifest the connection and similarities between the philosophy of Thoreau and the ancient worldview of Taoism.
Date: June 25, 2023
Creator: Thompson, Michael & Xu, Li
System: The UNT Digital Library
Sibling Aggression, Feeding Rates, and Hatch Rank of Nestling Red-Shouldered Hawks (Buteo lineatus) (open access)

Sibling Aggression, Feeding Rates, and Hatch Rank of Nestling Red-Shouldered Hawks (Buteo lineatus)

Article describes how, in many raptor species, hatching asynchrony results in a size hierarchy among nestlings, which may facilitate brood reduction by means of sibling aggression-induced mortality, especially in times of low food resources. The authors studied the influence of hatch rank, brood size, and brood age on aggression and feeding rates among Red-shouldered Hawk (Buteo lineatus) nestlings in suburban southwestern Ohio.
Date: May 25, 2023
Creator: Miller, Sara J.; Dykstra, Cheryl R.; Rolland, Virginie; Simon, Melinda M.; Hays, Jeffrey L. & Bednarz, James C.
System: The UNT Digital Library
Measurement of CP observables in B__ ->D_CPK__ decays and constraints on the CKM angle gamma (open access)

Measurement of CP observables in B__ ->D_CPK__ decays and constraints on the CKM angle gamma

Using the entire sample of 467 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, we perform a 'GLW' analysis of B{sup {+-}} {yields} D{sup {+-}} decays, using decay modes in which the neutral D meson decays to either CP-eigenstates or non-CP-eigenstates. We measure the partial decay rate charge asymmetries for CP-even and CP-odd D final states to be A{sub CP+} = 0.25 {+-} 0.06 {+-} 0.02 and A{sub CP-} = -0.09 {+-} 0.07 {+-} 0.02, respectively, where the first error is the statistical and the second is the systematic uncertainty. The parameter A{sub CP+} is different from zero with a significance of 3.6 standard deviations, constituting evidence for direct CP violation. We also measure the ratios of the charged-averaged B partial decay rates in CP and non-CP decays, R{sub CP+} = 1.18 {+-} 0.09 {+-} 0.05 and R{sub CP-} = 1.07 {+-} 0.08 {+-} 0.04. We infer frequentist confidence intervals for the angle {gamma} of the (db) unitarity triangle, for the strong phase difference {delta}{sub B}, and for the amplitude ratio r{sub B}, which are related to the B{sup -} {yields} D{sup -} decay amplitude by r{sub B}e{sup i({delta}{sub …
Date: August 25, 2010
Creator: del Amo Sanchez, P.; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J. et al.
System: The UNT Digital Library
Design considerations for a two-phase turbine (open access)

Design considerations for a two-phase turbine

A two-phase turbine, using a low-quality steam-water mixture as a working fluid, was designed, built, and tested in the laboratory. Two-phase fluids are found naturally in most geothermal fields throughout the world and can also be used in the conversion of waste heat from industrial sources. The thermodynamic and fluid-dynamic properties of such fluid mixtures are reviewed, with specific reference to the selection and design of an appropriate expander. Various types of practically realizable expanders are considered, and the choice of a single-stage, axial-flow, impulse turbine is explained. Also the basic design parameters, including sizing and blade and nozzle geometry, are described.
Date: May 25, 1978
Creator: Comfort, W. J., III & Beadle, C.W.
System: The UNT Digital Library
Thermal analysis of the FSP-1 fuel pin irradiation test (open access)

Thermal analysis of the FSP-1 fuel pin irradiation test

Thermal analysis of a pin from the FSP-1 fuels irradiation test has been completed. The purpose of the analysis was to provide predictions of fuel pin temperatures, determine the flow regime within the lithium annulus of the test assembly, and provide a standardized model for a consistent basis of comparison between pins within the test assembly. The calculations have predicted that the pin is operating at slightly above the test design temperatures and that the flow regime within the lithium annulus is a laminar buoyancy driven flow. 7 refs., 5 figs.
Date: July 25, 1990
Creator: Lyon, W. F., III
System: The UNT Digital Library