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Energy Efficiency Standards and Labels in North America: Opportunities for Harmonization (open access)

Energy Efficiency Standards and Labels in North America: Opportunities for Harmonization

To support the North American Energy Working Group's Expert Group on Energy Efficiency (NAEWG-EE), USDOE commissioned the Collaborative Labeling and Appliance Standards Program (CLASP) to prepare a resource document comparing current standards, labels, and test procedure regulations in Canada, Mexico, and the United States. The resulting document reached the following conclusions: Out of 24 energy-using products for which at least one of the three countries has energy efficiency regulations, three products -- refrigerators/freezers, split system central air conditioners, and room air conditioners -- have similar or identical minimum energy performance standards (MEPS) in the three countries. These same three products, as well as three-phase motors, have similar or identical test procedures throughout the region. There are 10 products with different MEPS and test procedures, but which have the short-term potential to develop common test procedures, MEPS, and/or labels. Three other noteworthy areas where possible energy efficiency initiatives have potential for harmonization are standby losses, uniform endorsement labels, and a new standard or label on windows. This paper explains these conclusions and presents the underlying comparative data.
Date: May 16, 2002
Creator: Vanwiemcgrory, Laura; Wiel, Stephen; Van Wie McGrory, Laura & Harrington, Lloyd
System: The UNT Digital Library
The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies (open access)

The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies

The National Ignition Facility (NIF), currently under construction at the University of California's Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, 351-nm laser system and a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. NIF is being built by the National Nuclear Security Administration and when completed will be the world's largest laser experimental system, providing a national center to study inertial confinement fusion and the physics of matter at extreme energy densities and pressures. NIF will provide 192 energetic laser beams that will compress small fusion targets to conditions where they will ignite and burn, liberating more energy than is required to initiate the fusion reactions. NIF experiments will allow the study of physical processes at temperatures approaching 100 million K and 100 billion times atmospheric pressure. These conditions exist naturally only in the interior of stars and in nuclear weapons explosions. In the course of designing the world's most energetic laser system, a number of significant technology breakthroughs have been achieved. Research is also underway to develop a shorter pulse capability on NIF for very high power and extreme electromagnetic field research and applications. We discuss here the technology challenges …
Date: October 16, 2002
Creator: Moses, E I & Wuest, C R
System: The UNT Digital Library
Fast Ignition: Physics Progress in the US Fusion Energy Program and Prospects for Achieving Ignition. (open access)

Fast Ignition: Physics Progress in the US Fusion Energy Program and Prospects for Achieving Ignition.

Fast ignition (FI) has significant potential advantages for inertial fusion energy and it is therefore being studied as an exploratory concept in the US fusion energy program. FI is based on short pulse isochoric heating of pre-compressed DT by intense beams of laser accelerated MeV electrons or protons. Recent experimental progress in the study of these two heating processes is discussed. The goal is to benchmark new models in order to predict accurately the requirements for full-scale fast ignition. An overview is presented of the design and experimental testing of a cone target implosion concept for fast ignition. Future prospects and conceptual designs for larger scale FI experiments using planned high energy petawatt upgrades of major lasers in the US are outlined. A long-term roadmap for FI is defined.
Date: October 16, 2002
Creator: Key, M. H.; Andersen, C.; Cowan, T.; Fisch, N.; Freeman, R.; Hatchett, S. et al.
System: The UNT Digital Library
Ion energy distribution functions of vacuum arc plasmas (open access)

Ion energy distribution functions of vacuum arc plasmas

The velocity distribution function of vacuum arc ions can be measured by a time-of-flight technique similar to a method originally proposed by Yushkov. The measuring principle makes use of the well-justified assumption that the ion drift velocity from the cathode spot region to a collector is approximately constant. It is shown that the negative time derivative of the collector current is directly proportional to the ion distribution function provided that the time-averaged source intensity (i.e., emission of ions from cathode spots) is constant until the arc is rapidly switched off. In the experiment, arc termination took about 700 ns, which is much faster than the decay of the ion current measured at the collector placed in more than 2 meters distance from the cathode. The experimental distribution functions for most cathode materials show one large peak with a tail and one or more small peaks at higher ion velocities. The distribution functions for some other materials exhibit several peaks. No conclusive answer can be given about the nature of these peaks. Arguments are presented that the peaks are not caused by different charge states or plasma contamination but rather due to insufficiently averaged source fluctuations and/or acceleration by plasma instabilities.
Date: September 16, 2002
Creator: Byon, Eungsun & Anders, Andre
System: The UNT Digital Library
Collider Tests of the Little Higgs Model (open access)

Collider Tests of the Little Higgs Model

The little Higgs model provides an alternative to traditional candidates for new physics at the TeV scale. The new heavy gauge bosons predicted by this model should be observable at the Large Hadron Collider (LHC). We discuss how the LHC experiments could test the little Higgs model by studying the production and decay of these particles.
Date: December 16, 2002
Creator: Burdman, Gustavo; Perelstein, Maxim & Pierce, Aaron
System: The UNT Digital Library
Wilson lines and symmetry breaking on orbifolds (open access)

Wilson lines and symmetry breaking on orbifolds

Gauge symmetry breaking by boundary conditions on a manifold is known to be equivalent to Wilson-line breaking through a background gauge field, and is therefore spontaneous. These equivalent pictures are related by a non-periodic gauge transformation. However, we find that boundary condition gauge symmetry breaking on orbifolds is explicit; there is no gauge where all the breaking can be attributed to a background gauge field. In the case of a five-dimensional SU(5) grand unified theory on S{sup 1} = Z{sub 2}, the vacuum with gauge symmetry broken to SU(3) x SU(2) x U(1) and that with SU(5) preserved are completely disconnected: there is no physical process which causes tunneling between the two. This allows a certain localized explicit breaking of SU(5) on one of the orbifold fixed points in the theory with SU(5) breaking. Split multiplets on this fixed point are shown not to induce violations of unitarity in scattering amplitudes.
Date: August 16, 2002
Creator: Hall, Lawrence J.; Murayama, Hitoshi & Nomura, Yasunori
System: The UNT Digital Library
Pressure dependence of donor excitation spectra in AlSb (open access)

Pressure dependence of donor excitation spectra in AlSb

We have investigated the behavior of ground to bound excited-state electronic transitions of Se and Te donors in AlSb as a function of hydrostatic pressure. Using broadband far-infrared Fourier transform spectroscopy, we observe qualitatively different behaviors of the electronic transition energies of the two donors. While the pressure derivative of the Te transition energy is small and constant, as might be expected for a shallow donor, the pressure derivatives of the Se transition energies are quadratic and large at low pressures, indicating that Se is actually a deep donor. In addition, at pressures between 30 and 50 kbar, we observe evidence of an anti-crossing between one of the selenium electronic transitions and a two-phonon mode.
Date: January 16, 2002
Creator: Hsu, L.; McCluskey, M. D. & Haller, E. E.
System: The UNT Digital Library
Proton polarization in neutral pion photo-production. (open access)

Proton polarization in neutral pion photo-production.

The authors present measurements of recoil proton polarization for {sup 1}H({rvec {gamma}},{rvec p}){pi}{sup 0} in and above the resonance region. These are the first data in this reaction for polarization transfer with circularly polarized photons. The results are compared to phase shift analyses and quark model calculations.
Date: July 16, 2002
Creator: Wijesooriya, K. & Collaboration, Jefferson Lab Hall A
System: The UNT Digital Library
Seismic low-frequency effects from oil-saturated reservoir zones (open access)

Seismic low-frequency effects from oil-saturated reservoir zones

We consider the frequency dependence of seismic reflections from a thin (compared to the dominant wavelength), fluid saturated reservoir for the cases of oil and water saturation. Reflections from a thin, water or oil-saturated layer have increased amplitude and delayed travel time at low frequencies if compared with reflections from a gas-saturated layer. This effect was observed for both ultrasonic lab data and seismic field data. One set of field data revealed high correlation of low frequency processed image for two different production horizons represented by fractured shale and sandstone. Another set was processed for the purpose of contouring of oil/water contact, and reveal very good correlation with available well data. The frequency dependent amplitude and phase reflection properties can be used for detecting and monitoring thin liquid saturated layers.
Date: April 16, 2002
Creator: Goloshubin, Gennady M.; Korneev, Valeri A. & Vingalov, Vjacheslav M.
System: The UNT Digital Library
Metal dusting research at Argonne National Laboratory. (open access)

Metal dusting research at Argonne National Laboratory.

The deposition of carbon from carbonaceous gaseous environments is prevalent in many chemical and petrochemical processes such as reforming systems, syngas production systems, and iron reduction plants. One of the major consequences of carbon deposition is the degradation of structural materials by a phenomenon known as ''metal dusting.'' There are two major issues of importance in metal dusting. First is formation of carbon and subsequent deposition of carbon on metallic materials. Second is the initiation of metal dusting degradation of the alloy. Details are presented on a research program that is underway at Argonne National Laboratory to study the metal dusting phenomenon from a fundamental scientific base involving laboratory research in simulated process conditions and field testing of materials in actual process environments. The project has participation from the U.S. chemical industry, alloy manufacturers, and the Materials Technology Institute, which serves the chemical process industry.
Date: September 16, 2002
Creator: Natesan, K.; Zeng, Z.; Maroni, V. A.; Soppet, W. K. & Rink, D. L.
System: The UNT Digital Library
Raf-1-induced growth arrest in human mammary epithelial cells is p16-independent and is overcome in immortal cells during conversion (open access)

Raf-1-induced growth arrest in human mammary epithelial cells is p16-independent and is overcome in immortal cells during conversion

None
Date: January 16, 2002
Creator: Olsen, Catherine L.; Gardie, Betty; Yaswen, Paul & Stampfer, Martha R.
System: The UNT Digital Library
Liquid-film assisted formation of alumina/niobium interfaces (open access)

Liquid-film assisted formation of alumina/niobium interfaces

Alumina has been joined at 1400 degrees C using niobium-based interlayers. Two different joining approaches were compared: solid-state diffusion bonding using a niobium foil as an interlayer, and liquid-film assisted bonding using a multilayer copper/niobium/copper interlayer. In both cases, a 127-(mu)m thick niobium foil was used; =1.4-(mu)m or =3-(mu)m thick copper films flanked the niobium. Room-temperature four-point bend tests showed that the introduction of a copper film had a significant beneficial effect on the average strength and the strength distribution. Experiments using sapphire substrates indicated that during bonding the initially continuous copper film evolved into isolated copper-rich droplets/particles at the sapphire/interlayer interface, and extensive regions of direct bonding between sapphire and niobium. Film breakup appeared to initiate at either niobium grain boundary ridges, or at asperities or irregularities on the niobium surface that caused localized contact with the sapphire.
Date: June 16, 2002
Creator: Sugar, Joshua D.; McKeown, Joseph T.; Marks, Robert A. & Glaeser, Andreas M.
System: The UNT Digital Library
Assessing non-uniqueness: An algebraic approach (open access)

Assessing non-uniqueness: An algebraic approach

Geophysical inverse problems are endowed with a rich mathematical structure. When discretized, most differential and integral equations of interest are algebraic (polynomial) in form. Techniques from algebraic geometry and computational algebra provide a means to address questions of existence and uniqueness for both linear and non-linear inverse problem. In a sense, the methods extend ideas which have proven fruitful in treating linear inverse problems.
Date: September 16, 2002
Creator: Vasco, Don W.
System: The UNT Digital Library
Fabrication techniques for septum magnets at the APS. (open access)

Fabrication techniques for septum magnets at the APS.

The design, construction, and installation of pulsed septum magnets for particle accelerators presents many challenges for the magnet engineer. Issues associated with magnet core structure design, component alignment, weldment design, and electrical insulation choices are among those requiring careful attention. The designs of the six septum magnets required for the APS facility have evolved since operation began in 1996. Improvements in the designs have provided better injection/extraction performance parameters and extended the machine reliability to meet the requirements of a world-class, third-generation synchrotron radiation facility. Details of the techniques used to address issues involved in producing septum magnets at the APS are described here to aid magnet engineers in the fabrication of future septum magnets.
Date: September 16, 2002
Creator: Jaski, M.; Thompson, K.; Kim, S.; Friedsam, H.; Toter, W. & Humbert, J.
System: The UNT Digital Library
Results of the SNS front end commissioning at Berkeley Lab (open access)

Results of the SNS front end commissioning at Berkeley Lab

The Front-End Systems (FES) for the Spallation Neutron Source (SNS) project comprise an rf-driven H{sup -} ion source, an electrostatic 2-lens LEBT, a 2.5 MeV RFQ, followed by a 14-quadrupole, 4-rebuncher MEBT including traveling-wave fast choppers. The nominal 2.5 MeV H{sup -} beam has a current of 38 mA at a repetition rate of 60 Hz and 1 ms pulse length, for a macro duty-factor of 6%, and is chopped at a rate of approximately 1 MHz with a mini duty-factor of 68%. The normalized rms beam emittance at the MEBT exit, matching the first tank of a 402.5 MHz Alvarez linac, is measured to be approximately 0.3 {pi} mm mrad. Diagnostic elements include wire scanners, BPMs, fast current monitors, a slit-harp emittance device and RFQ field monitoring probes. The results of the beam commissioning and the operation of the RFQ and diagnostic instrumentation are reported. The entire FES was shut down at LBNL at the end of May 2002 and will be recommissioned at ORNL prior to installation of the drift-tube linac.
Date: August 16, 2002
Creator: Ratti, A.; Ayers, J. J.; Doolittle, L.; Greer, J. B.; Keller, R.; Lewis, S. et al.
System: The UNT Digital Library
RADIATION LITMUS PAPER (open access)

RADIATION LITMUS PAPER

None
Date: February 16, 2002
Creator: WARNER, BENJAMIN P; JOHNS, DEIDRE M; D'ALESSIO, JOSEPH A & SHEAFE, KIMBERLY S
System: The UNT Digital Library
Electroproduction of strangeness on light nuclei. (open access)

Electroproduction of strangeness on light nuclei.

The A(e,e{prime} K{sup +})YX reaction has been investigated in Hall C at Jefferson Laboratory for 6 different targets. Data were taken for Q{sup 2} {approx} 0.35 and 0.5 GeV{sup 2} at a beam energy of 3.245 GeV for {sup 1}H, {sup 2}H, {sup 3}He, {sup 4}He, C and Al targets. The missing mass spectra are fitted with Monte Carlo simulations taking into account the production of {Lambda} and {Sigma}{sup 0} hyperon production off the proton, and {Sigma}{sup -} off the neutron. Models for quasifree production are compared to the data, excess yields close to threshold are attributed to FSI. Evidence for {Lambda}-hypernuclear bound states is seen for {sup 3,4}He targets.
Date: May 16, 2002
Creator: Dohrmann, F.; Abbott, D.; Ahmidouch, A.; Ambrozewicz, P.; Armstrong, C. S.; Arrington, J. et al.
System: The UNT Digital Library
Sloan Digital Sky Survey photometric telescope automation and observing software (open access)

Sloan Digital Sky Survey photometric telescope automation and observing software

The photometric telescope (PT) provides observations necessary for the photometric calibration of the Sloan Digital Sky Survey (SDSS). Because the attention of the observing staff is occupied by the operation of the 2.5 meter telescope which takes the survey data proper, the PT must reliably take data with little supervision. In this paper we describe the PT's observing program, MOP, which automates most tasks necessary for observing. MOP's automated target selection is closely modeled on the actions a human observer might take, and is built upon a user interface that can be (and has been) used for manual operation. This results in an interface that makes it easy for an observer to track the activities of the automating procedures and intervene with minimum disturbance when necessary. MOP selects targets from the same list of standard star and calibration fields presented to the user, and chooses standard star fields covering ranges of airmass, color, and time necessary to monitor atmospheric extinction and produce a photometric solution. The software determines when additional standard star fields are unnecessary, and selects survey calibration fields according to availability and priority. Other automated features of MOP, such as maintaining the focus and keeping a night log, …
Date: October 16, 2002
Creator: Eric H. Neilsen, Jr. et al.
System: The UNT Digital Library
Aspects of Parallel Simulation of High Intensity Beams in Hadron Rings. (open access)

Aspects of Parallel Simulation of High Intensity Beams in Hadron Rings.

None
Date: October 16, 2002
Creator: Luccio, A. U. & D Imperio, N. L.
System: The UNT Digital Library
Electron Donor Acceptor Interactions. Final Progress Report (open access)

Electron Donor Acceptor Interactions. Final Progress Report

The Gordon Research Conference (GRC) on Electron Donor Acceptor Interactions was held at Salve Regina University, Newport, Rhode Island, 8/11-16/02. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.
Date: August 16, 2002
Creator: unknown
System: The UNT Digital Library
Modeling light scattering from diesel soot particles (open access)

Modeling light scattering from diesel soot particles

The Mie model is widely used to analyze light scattering from particulate aerosols. The Diesel Particle Scatterometer (DPS), for example, determines the size and optical properties of diesel exhaust particles that are characterized by measuring three angle-dependent elements of the Mueller scattering matrix. These elements are then fitted using Mie calculations with a Levenburg-Marquardt optimization program. This approach has achieved good fits for most experimental data. However, in many cases, the predicted real and imaginary parts of the index of refraction were less than that for solid carbon. To understand this result and explain the experimental data, we present an assessment of the Mie model by use of a light scattering model based on the coupled dipole approximation. The results indicate that the Mie calculation can be used to determine the largest dimension of irregularly shaped particles at sizes characteristic of Diesel soot and, for particles of known refractive index, tables can be constructed to determine the average porosity of the particles from the predicted index of refraction.
Date: July 16, 2002
Creator: Hull, Patricia; Shepherd, Ian & Hunt, Arlon
System: The UNT Digital Library
Cyr61 promotes breast tumorigenesis and cancer progression (open access)

Cyr61 promotes breast tumorigenesis and cancer progression

Cyr61, a member of the CCN family of genes, is an angiogenic factor. We have shown that it is overexpressed in invasive and metastatic human breast cancer cells and tissues. Here, we investigated whether Cyr61 is necessary and/or sufficient to bypass the ''normal'' estrogen (E2) requirements for breast cancer cell growth. Our results demonstrate that under E2-depleted condition, Cyr61 is sufficient to induce MCF-7 cells grow in the absence of E2. MCF-7 cells transfected with Cyr61 (MCF-7/Cyr61) became E2-independent but still E2-responsive. On the other hand, MCF-7/vector cells remain E2-dependent. MCF-7/Cyr61 cells acquire an antiestrogen-resistant phenotype, one of the most common clinical occurrences during breast cancer progression. MCF-7/Cyr61 cells are anchorage-independent and capable of forming Matrigel outgrowth patterns in the absence of E2. ERa expression in MCF-7/Cyr61 cells is decreased although still functional. Additionally, MCF-7/Cyr61 cells are tumorigenic in ovariectomized athymic nude mice. The tumors resemble human invasive carcinomas with increased vascularization and overexpression of vascular endothelial growth factor (VEGF). Our results demonstrate that Cyr61 is a tumor-promoting factor and a key regulator of breast cancer progression. This study provides evidence that Cyr61 is sufficient to induce E2-independence and anti-E2 resistance, and to promote invasiveness in vitro, and to induce …
Date: January 16, 2002
Creator: Tsai, Miaw-Sheue; Bogart, Daphne F.; Castaneda, Jessica M.; Li, Patricia & Lupu, Ruth
System: The UNT Digital Library
A New Assessment of the LOFT-Wyle Blowdown Test WSB03R Using RELAP5-3D (open access)

A New Assessment of the LOFT-Wyle Blowdown Test WSB03R Using RELAP5-3D

The RELAP-3D (version bt03) computer program was used to assess the LOFT-Wyle blowdown test (WSB03R). The primary goal of this new assessment is to represent faithfully the experimental facility and instrumentation using the latest three-dimensional fluid flow modeling capability available in RELAP5-3D. In addition, since RELAP5-3D represents a relatively new and significant upgrade to the capabilities of the RELAP5 series of computer programs, this study serves to add to its growing assessment base. The LOFT-Wyle Transient Fluid Calibration test facility consisted of an approximately 5.4m3 pressure vessel with a flow skirt which created an annulus that acted as a downcomer. An instrumented blowdown loop with an orfice was connected to the downcomer. This facility, built to calibrate the orfices used in several of the LOFT experiments, simulated the LOFT reactor vessel and broken loop cold leg. For the present assessment an existing RELAP5 model developed at INEEL was corrected and upgraded. The model corrections included: (1) employing the proper measured downcomer thickness, (2) positioning the experimental instrumentation in its correct location, and (3) setting the fluid conditions to their measured initial values. Model upgrades included: (1) use of a more finely-detailed fluid component nodalization, (2) explicit modeling of the experimental …
Date: April 16, 2002
Creator: Bandini, B. R.; Aumiller, D. L. & Tomlinson, E. T.
System: The UNT Digital Library
Are recoil polarization measurements of G{sup P}{ovr sub E}/G{sup P}{ovr sub M} consistent with Rosenbluth separation data? (open access)

Are recoil polarization measurements of G{sup P}{ovr sub E}/G{sup P}{ovr sub M} consistent with Rosenbluth separation data?

Recent recoil polarization measurements in Hall A at Jefferson Lab show that the ratio of the electric to magnetic form factors for the proton decreases significantly with increasing Q{sup 2}. This contradicts previous Rosenbluth measurements which indicate approximate scaling of the form factors ({micro}{sub p} G{sub E}{sup p}(Q{sup 2})/G{sub M}{sup p} (Q{sup 2}) {approx} 1). The cross section measurements were reanalyzed to try and understand the source of this discrepancy. They find that the Rosenbluth measurements are consistent when normalization uncertainties are taken into account, and that the discrepancy cannot come from errors in one or two data sets. If there is a problem in the Rosenbluth data, it must be a systematic, {epsilon}-dependent uncertainty affecting several experiments.
Date: May 16, 2002
Creator: Arrington, J.
System: The UNT Digital Library