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Using Contingent Valuation to Explore Willingness to Pay forRenewable Energy: A Comparison of Collective and Voluntary PaymentVehicles (open access)
Relationships between walking and percentiles of adiposity inolder and younger men (open access)

Relationships between walking and percentiles of adiposity inolder and younger men

To assess the relationship of weekly walking distance to percentiles of adiposity in elders (age {ge} 75 years), seniors (55 {le} age <75 years), middle-age men (35 {le} age <55 years), and younger men (18 {le} age <35 years old). Cross-sectional analyses of baseline questionnaires from 7,082 male participants of the National Walkers Health Study. The walkers BMIs were inversely and significantly associated with walking distance (kg/m{sup 2} per km/wk) in elders (slope {+-} SE: -0.032 {+-} 0.008), seniors (-0.045 {+-} 0.005), and middle-aged men (-0.037 {+-} 0.007), as were their waist circumferences (-0.091 {+-} 0.025, -0.045 {+-} 0.005, and -0.091 {+-} 0.015 cm per km/wk, respectively), and these slopes remained significant when adjusted statistically for reported weekly servings of meat, fish, fruit, and alcohol. The declines in BMI associated with walking distance were greater at the higher than lower percentiles of the BMI distribution. Specifically, compared to the decline at the 10th BMI percentile, the decline in BMI at the 90th percentile was 5.1-fold greater in elders, 5.9-fold greater in seniors, and 6.7-fold greater in middle-age men. The declines in waist circumference associated with walking distance were also greater among men with broader waistlines. Exercise-induced weight loss (or self-selection) …
Date: June 1, 2005
Creator: Williams, Paul T.
System: The UNT Digital Library
Biomimetic bonelike composites and novel bioactive glasscoatings (open access)

Biomimetic bonelike composites and novel bioactive glasscoatings

Metallic orthopaedic implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel coatings to improve implant osseointegration and in the development of a new generation of hybrid organic-inorganic implant materials specifically designed for orthopaedic applications.
Date: June 1, 2005
Creator: Tomsia, A.P.; Saiz, E.; Song, J. & Bertozzi, C.R.
System: The UNT Digital Library
Can Deployment of Renewable Energy and Energy Efficiency PutDownward Pressure on Natural Gas Prices (open access)

Can Deployment of Renewable Energy and Energy Efficiency PutDownward Pressure on Natural Gas Prices

High and volatile natural gas prices have increasingly led to calls for investments in renewable energy and energy efficiency. One line of argument is that deployment of these resources may lead to reductions in the demand for and price of natural gas. Many recent U.S.-based modeling studies have demonstrated that this effect could provide significant consumer savings. In this article we evaluate these studies, and benchmark their findings against economic theory, other modeling results, and a limited empirical literature. We find that many uncertainties remain regarding the absolute magnitude of this effect, and that the reduction in natural gas prices may not represent an increase in aggregate economic wealth. Nonetheless, we conclude that many of the studies of the impact of renewable energy and energy efficiency on natural gas prices appear to have represented this effect within reason, given current knowledge. These studies specifically suggest that a 1% reduction in U.S. natural gas demand could lead to long-term average wellhead price reductions of 0.8% to 2%, and that each megawatt-hour of renewable energy and energy efficiency may benefit natural gas consumers to the tune of at least $7.5 to $20.
Date: June 1, 2005
Creator: Wiser, Ryan & Bolinger, Mark
System: The UNT Digital Library
Mechanical Analysis of the Nb3Sn Dipole Magnet HD1 (open access)

Mechanical Analysis of the Nb3Sn Dipole Magnet HD1

The Superconducting Magnet Group at Lawrence Berkeley National Laboratory (LBNL) has recently fabricated and tested HD1, a Nb3Sn dipole magnet. The magnet reached a 16 T field, and exhibited training quenches in the end regions and in the straight section. After the test, HD1 was disassembled and inspected, and a detailed 3D finite element mechanical analysis was done to investigate for possible quench triggers. The study led to minor modifications to mechanical structure and assembly procedure, which were verified in a second test (HD1b). This paper presents the results of the mechanical analysis, including strain gauge measurements and coil visual inspection. The adjustments implemented in the magnet structure are reported and their effect on magnet training discussed.
Date: June 1, 2005
Creator: Ferracin, Paolo; Bartlett, Scott E.; Caspi, Shlomo; Dietderich, Daniel R.; Gourlay, Steve A.; Hannaford, Charles R. et al.
System: The UNT Digital Library
On Water Flow in Hot Fractured Rock -- A Sensitivity Study on theImpact of Fracture-Matrix Heat Transfer (open access)

On Water Flow in Hot Fractured Rock -- A Sensitivity Study on theImpact of Fracture-Matrix Heat Transfer

Dual-continuum models have been widely used in modeling flowand transport in fractured porous rocks. Among many other applications,dual-continuum approaches were utilized in predictive models of thethermal-hydrological conditions near emplacement tunnels (drifts) atYucca Mountain, Nevada, the proposed site for a radioactive wasterepository in the U.S. In unsaturated formations such as those at YuccaMountain, the magnitude of mass and heat exchange between the twocontinua fracture network and matrix is largely dependent on the flowcharacteristics in the fractures, because channelized finger-type flowstrongly reduces the interface area between the matrix surfaces and theflowing liquid. This effect may have important implications, for example,during the time period that the fractured rock near the repository driftswould be heated above the boiling point of water. Depending on themagnitude of heat transfer from the matrix, water percolating down thefractures will either boil off in the hot rock region above drifts or maypenetrate all the way to the drift walls and possibly seep into the opencavities. In this paper, we describe a sensitivity analysis using avariety of approaches to treat fracture-matrix interaction in athree-dimensional dual-continuum setting. Our simulation example is alaboratory heater experiment described in the literature that providesevidence of rapid water flow in fractures, leading to drift seepagedespite above-boiling …
Date: June 1, 2005
Creator: Birkholzer, Jens T. & Zhang, Yingqi
System: The UNT Digital Library
Development of a Large Aperture Nb3Sn Racetrack Quadrupole Magnet (open access)

Development of a Large Aperture Nb3Sn Racetrack Quadrupole Magnet

The U.S. LHC Accelerator Research Program (LARP), a collaboration between BNL, FNAL, LBNL, and SLAC, has among its major objectives the development of advanced magnet technology for an LHC luminosity upgrade. The LBNL Superconducting Magnet Group supports this program with a broad effort involving design studies, Nb{sub 3}Sn conductor development, mechanical models, and basic prototypes. This paper describes the development of a large aperture Nb{sub 3}Sn racetrack quadrupole magnet using four racetrack coils from the LBNL Subscale Magnet (SM) Program. The magnet provides a gradient of 95 T/m in a 110 mm bore, with a peak field in the conductor of 11.2 T. The coils are pre-stressed by a mechanical structure based on a pre-tensioned aluminum shell, and axially supported with aluminum rods. The mechanical behavior has been monitored with strain gauges and the magnetic field has been measured. Results of the test are reported and analyzed.
Date: June 1, 2005
Creator: Ferracin, Paolo; Bartlett, Scott E.; Caspi, Shlomo; Dietderich, Daniel R.; Gourlay, Steve A.; Hannaford, Charles R. et al.
System: The UNT Digital Library
SQUID-Detected In Vivo MRI at Microtesla Magnetic Fields (open access)

SQUID-Detected In Vivo MRI at Microtesla Magnetic Fields

We use a low transition temperature (T{sub c}) Super-conducting Quantum Interference Device (SQUID) to perform in vivo magnetic resonance imaging (MRI) at magnetic fields around 100 microtesla, corresponding to proton Larmor frequencies of about 5 kHz. In such low fields, broadening of the nuclear magnetic resonance lines due to inhomogeneous magnetic fields and susceptibility variations of the sample are minimized, enabling us to obtain high quality images. To reduce environmental noise the signal is detected by a second-order gradiometer, coupled to the SQUID, and the experiment is surrounded by a 3-mm thick Al shield. To increase the signal-to-noise ratio (SNR), we prepolarize the samples in a field up to 100 mT. Three-dimensional images are acquired in less than 6 minutes with a standard spin-echo phase-encoding sequence. Using encoding gradients of {approx}100 {micro}T/m we obtain three-dimensional images of bell peppers with a resolution of 2 x 2 x 8 mm{sup 3}. Our system is ideally suited to acquiring images of small, peripheral parts of the human body such as hands and arms. In vivo images of an arm, acquired at 132 {micro}T, show 24-mm sections of the forearm with a resolution of 3 x 3 mm{sup 2} and a SNR of …
Date: June 1, 2005
Creator: Moble, Michael; Myers, Whittier R; Lee, SeungKyun; Kelso, Nathan; Hatridge, Michael; Pines, Alexander et al.
System: The UNT Digital Library
A First Look at Modern Enterprise Traffic (open access)

A First Look at Modern Enterprise Traffic

While wide-area Internet traffic has been heavily studied for many years, the characteristics of traffic inside Internet enterprises remain almost wholly unexplored. Nearly all of the studies of enterprise traffic available in the literature are well over a decade old and focus on individual LANs rather than whole sites. In this paper we present a broad overview of internal enterprise traffic recorded at a medium-sized site. The packet traces span more than 100 hours, over which activity from a total of several thousand internal hosts appears. This wealth of data--which we are publicly releasing in anonymized form--spans a wide range of dimensions. While we cannot form general conclusions using data from a single site, and clearly this sort of data merits additional in-depth study in a number of ways, in this work we endeavor to characterize a number of the most salient aspects of the traffic. Our goal is to provide a first sense of ways in which modern enterprise traffic is similar to wide-area Internet traffic, and ways in which it is quite different.
Date: June 1, 2005
Creator: Pang, Ruoming; Mark Allman, Mark; Bennett, Mike; Lee, Jason; Paxson, Vern & Tierney, Brian
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 (open access)

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.
System: The UNT Digital Library
Nuclear effects in high-p(T) production of direct photons and neutral mesons (open access)

Nuclear effects in high-p(T) production of direct photons and neutral mesons

The authors present results on the production of direct photons, {pi}{sup 0}, {eta} mesons on nuclear targets at large transverse momenta (p{sub T}). The data are from 530 and 800 GeV/c proton beams and 515 GeV/c {pi}{sup -} beams incident upon copper and beryllium targets that span the kinematic range of 1.0 < p{sub T} {approx}< 10 GeV/c at central rapidities.
Date: June 1, 2005
Creator: Apanasevich, L.; Bacigalupi, J.; Baker, W.; Begel, M.; Blusk, S.; Bromberg, C. et al.
System: The UNT Digital Library
Physics of heavy flavor at CDF (open access)

Physics of heavy flavor at CDF

Results on physics of heavy flavor at CDF are reported. Selected measurements of Branching Ratios and CP asymmetry in B{sup 0} and B{sub s}{sup 0}, lifetime difference of B{sub s}{sup 0} CP eigenstates and a precise measurement of the B{sub c} mass are presented.
Date: June 1, 2005
Creator: Torre, Stefano & /Siena U. /INFN, Pisa
System: The UNT Digital Library
Search for a strongly decaying neutral charmed pentaquark (open access)

Search for a strongly decaying neutral charmed pentaquark

We present a search for a charmed pentaquark decaying strongly to D{sup (*)}-p. Finding no evidence for such a state, we set limits on the cross section times branching ratio relative to D*{sup -} and D{sup -} under particular assumptions about the production mechanism.
Date: June 1, 2005
Creator: Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
System: The UNT Digital Library
A preliminary assessment of the electron cloud effect for the FNAL main injector upgrade (open access)

A preliminary assessment of the electron cloud effect for the FNAL main injector upgrade

None
Date: June 1, 2005
Creator: Furman, M. A.
System: The UNT Digital Library
D0 Higgs physics results (open access)

D0 Higgs physics results

We have searched for the Standard Model (SM) and non Standard Model Higgs bosons using of about 200-260 pb{sup -1} of data collected with the upgraded Run II D0 detector at Fermilab Tevatron. Low-mass SM Higgs boson is searched in the associated production with W or Z and limits are placed on the cross section and the kinematic properties of the W or Z plus heavy flavor production. SM Higgs boson with mass greater than 135 GeV is searched for in its dominant decay mode WW with W's decaying into electron or muon final states. Non SM Higgs searches are done in the associated production of neutral SUSY Higgs with b quarks. Data are compared to various predictions and the limits are derived on model parameters.
Date: June 1, 2005
Creator: Rani, K. Jyothsna & Inst., /Tata
System: The UNT Digital Library
Performance analysis of HD1: a 16 Tesla Nb3Sn dipole Magnet (open access)

Performance analysis of HD1: a 16 Tesla Nb3Sn dipole Magnet

The Superconducting Magnet Group at Lawrence Berkeley National Laboratory (LBNL) has been developing technology for high field accelerator magnets from brittle conductors. HD1 is a single bore block dipole magnet using two, double-layer Nb{sub 3}Sn flat racetrack coils. The magnet was tested in October 2003 and reached a bore peak field of 16 T (94.5% of short sample). The average quench current plateau appeared to be limited by 'stick slip' conductor motions. Diagnostics recorded quench origins and preload distributions. Cumulative deformation of the mechanical structure has been observed. Quench velocity in different field regions has been measured and compared with model predictions. The results obtained during the HD1 test are presented and discussed.
Date: June 1, 2005
Creator: Mattafirri, S.; Bartlett, S. E.; Bish, P. A.; Caspi, S.; Dietderich, D. R.; Ferracin, P. et al.
System: The UNT Digital Library
Correlation Between Strand Stability and Magnet Performance (open access)

Correlation Between Strand Stability and Magnet Performance

Magnet programs at BNL, LBNL and FNAL have observed instabilities in high J{sub c} Nb{sub 3}Sn strands and magnets made from these strands. This paper correlates the strand stability determined from a short sample-strand test to the observed magnet performance. It has been observed that strands that carry high currents at high fields (greater than 10 T) cannot sustain these same currents at low fields (1-3 T) when the sample current is fixed and the magnetic field is ramped. This suggests that the present generation of strand is susceptible to flux jumps (FJ). To prevent flux jumps from limiting stand performance, one must accommodate the energy released during a flux jump. To better understand FJ this work has focused on wire with a given sub-element diameter and shows that one can significantly improve stability by increasing the copper conductivity (higher residual resistivity ratio, RRR, of the Cu). This increased stability significantly improves the conductor performance and permits it to carry more current.
Date: June 1, 2005
Creator: Dietderich, D. R.; Bartlett, S. E.; Caspi, S.; Ferracin, P.; Gourlay, S. A.; Higley, H. C. et al.
System: The UNT Digital Library
Design of HD2: a 15 T Nb3Sn dipole with a 35 mm bore (open access)

Design of HD2: a 15 T Nb3Sn dipole with a 35 mm bore

The Nb{sub 3}Sn dipole HD1, recently fabricated and tested at LBNL, pushes the limits of accelerator magnet technology into the 16 T field range, and opens the way to a new generation of HEP colliders. HD1 is based on a flat racetrack coil configuration and has a 10 mm bore. These features are consistent with the HD1 goals: exploring the Nb{sub 3}Sn conductor performance limits at the maximum fields and under high stress. However, in order to further develop the block-coil geometry for future high-field accelerators, the bore size has to be increased to 30-50 mm. With respect to HD1, the main R&D challenges are: (a) design of the coil ends, to allow a magnetically efficient cross-section without obstructing the beam path; (b) design of the bore, to support the coil against the pre-load force; (c) correction of the geometric field errors. HD2 represents a first step in addressing these issues, with a central dipole field above 15 T, a 35 mm bore, and nominal field harmonics within a fraction of one unit. This paper describes the HD2 magnet design concept and its main features, as well as further steps required to develop a cost-effective block-coil design for future high-field, …
Date: June 1, 2005
Creator: Sabbi, G.; Bartlett, S. E.; Caspi, S.; Dietderich, D. R.; Ferracin, P.; Gourlay, S. A. et al.
System: The UNT Digital Library
Effects of CO2 Hydrate on Deep-Sea Foraminiferal Assemblages (open access)

Effects of CO2 Hydrate on Deep-Sea Foraminiferal Assemblages

THE EFFECTS OF CO2 HYDRATE ON DEEP-SEA FORAMINIFERAL ASSEMBLAGES E. R. Ricketts*, J. P. Kennett and T. M. Hill Department of Geological Sciences University of California, Santa Barbara, CA USA Jim Barry Monterey Bay Aquarium Research Institute Moss Landing, CA USA ABSTRACT This study, conducted with the Monterey Bay Aquarium Research Institute (MBARI), is the first to investigate potential effects of CO2 hydrates on benthic microfossils, specifically foraminifera. The experiment was conducted in September 2003 aboard the R/V Western Flier using the ROV Tiburon. Experimental (CO2 exposed) and control cores were collected at 3600m and stained to distinguish live (stained) from dead (unstained) individuals. Foraminifera are ideal because of differing test composition (calcareous and agglutinated) and thickness, and diverse epifaunal and infaunal depth preferences. The effects of the CO2 on assemblages have been tracked both vertically (10cm depth) and horizontally, and between live and dead individuals. Increased mortality and dissolution of calcareous forms resulted from exposure to CO2 hydrate. Preliminary results suggest several major effects on surface sediment assemblages: 1) total number of foraminifera in a sample decreases; 2) foraminiferal diversity decreases in both stained and unstained specimens. The number of planktonic and hyaline calcareous tests declines greatly, with milliolids …
Date: June 1, 2005
Creator: Ricketts, E. R.; Kennett, J. P.; Hill, T. M. & Barry, J. P.
System: The UNT Digital Library
The Interaction of a Circular Synthetic Jet with a Cross-Flow Boundary Layer (open access)

The Interaction of a Circular Synthetic Jet with a Cross-Flow Boundary Layer

The interaction of a circular synthetic jet with a laminar cross-flow boundary layer was investigated experimentally in the Matched-Index-of-Refraction flow facility at Idaho National Laboratory. Two orifice orientations were investigated, straight and inclined. For each orifice, phase-averaged and time-averaged PIV measurements were made at L◦/D◦ = 1.0 and 2.0 with ReU◦ = 250 and r = 1.12. Refractive index matching between the working fluid and the model material permitted experimental measurements of the flow field inside the actuator orifice and cavity simultaneously. At L◦/D◦ = 1.0, the vortex ring formed at the orifice during the expulsion portion of the actuator cycle blocks the boundary layer causing the flow to divert over and around the ring. This vortex ring does not escape the near-vicinity of the orifice and is subsequently re-ingested. At the same stroke, inclining the orifice axis 30◦ downstream leads to a jet comprised of a train of vortex rings that penetrates the cross-flow. At L◦/D◦ = 2.0, both the straight and inclined orifices create large discrete vortex rings that penetrate deep into the cross-flow, and consequently do not affect the boundary layer much beyond the near-field of the orifice.
Date: June 1, 2005
Creator: McEligot, D. M.; Pink, R. J.; Shuster, Jennifer M. & Smith, Douglas R.
System: The UNT Digital Library
Voluntary Agreements for Energy Efficiency or GHG EmissionsReduction in Industry: An Assessment of Programs Around the World (open access)

Voluntary Agreements for Energy Efficiency or GHG EmissionsReduction in Industry: An Assessment of Programs Around the World

Voluntary agreements for energy efficiency improvement and reduction of energy-related greenhouse gas (GHG) emissions have been a popular policy instrument for the industrial sector in industrialized countries since the 1990s. A number of these national-level voluntary agreement programs are now being modified and strengthened, while additional countries--including some recently industrialized and developing countries--are adopting these type of agreements in an effort to increase the energy efficiency of their industrial sectors.Voluntary agreement programs can be roughly divided into three broad categories: (1) programs that are completely voluntary, (2) programs that use the threat of future regulations or energy/GHG emissions taxes as a motivation for participation, and (3) programs that are implemented in conjunction with an existing energy/GHG emissions tax policy or with strict regulations. A variety of government-provided incentives as well as penalties are associated with these programs. This paper reviews 23 energy efficiency or GHG emissions reduction voluntary agreement programs in 18 countries, including countries in Europe, the U.S., Canada, Australia, New Zealand, Japan, South Korea, and Chinese Taipei (Taiwan) and discusses preliminary lessons learned regarding program design and effectiveness. The paper notes that such agreement programs, in which companies inventory and manage their energy use and GHG emissions to …
Date: June 1, 2005
Creator: Price, Lynn
System: The UNT Digital Library
C. Judson King of UC Berkeley (open access)

C. Judson King of UC Berkeley

In the middle of the UC Berkeley campus, next to the Main Library, South Hall is the last surviving building from the original campus, founded about 135 years ago. A tiny tree-shaded appendix to this venerated classical building houses Berkeley's Center for Studies in Higher Education, directed by C. Judson King, former Provost and Senior Vice President--Academic Affairs of the ten-campus University of California and long-time Professor of Chemical Engineering at Berkeley. Jud came to Berkeley in 1963 as assistant professor of chemical engineering, following receipt of a doctor's degree from MIT and a subsequent short appointment as director of the MIT chemical engineering practice school station at what was then Esso (now Exxon) in New Jersey. His undergraduate degree is from Yale. Starting with his MIT doctoral dissertation on gas absorption, Jud has devoted much of his professional career to separation processes. His teaching and research activities have been primarily concerned with separation of mixtures with emphasis on liquid-liquid extraction and drying. As a consultant to Procter and Gamble, he contributed to the technology of making instant coffee. His life-long activities in hiking and camping stimulated Jud's interest in the manufacture of freeze-dried foods (e.g. turkey meat) to minimize …
Date: June 1, 2005
Creator: Prausnitz, John
System: The UNT Digital Library
SciDAC advances and applications in computational beam dynamics (open access)

SciDAC advances and applications in computational beam dynamics

None
Date: June 1, 2005
Creator: Ryne, R.; Abell, D.; Adelmann, A.; Amundson, J.; Bohn, C.; Cary, J. et al.
System: The UNT Digital Library
Thermally Activated Cooling: A Regional Approach for EstimatingBuilding Adoption (open access)

Thermally Activated Cooling: A Regional Approach for EstimatingBuilding Adoption

This paper examines the economic potential for thermally-activated cooling (TAC) technologies as a component of distributed energy resource (DER) systems in California. A geographic information system (GIS) is used to assess the regional variation of TAC potential and to visualize the geographic pattern of potential adoption. The economic potential and feasibility of DER systems in general, and especially TAC, is highly dependent on regional factors such as retail electricity rates, building cooling loads, and building heating loads. Each of these factors varies with location, and their geographic overlap at different sites is an important determinant in a market assessment of DER and TAC. This analysis uses system payback period as the metric to show the regional variation of TAC potential in California office buildings. The DER system payback with and without TAC is calculated for different regions in California using localized values of retail electricity rates and the weather-dependent variation in building cooling and heating loads. This GIS-based method has numerous applications in building efficiency studies where geographically dependent variables, such as space cooling and heating energy use, play an important role.
Date: June 1, 2005
Creator: Edwards, Jennifer L. & Marnay, Chris
System: The UNT Digital Library