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[Fox 4 KDFW Good Day, 2004-01-01] (open access)

[Fox 4 KDFW Good Day, 2004-01-01]

Article about Evel Knievel's appearance at Will Rogers Coliseum, Franklin Covey's advice on New Year's resolutions, the launching of Brilliant Magazine, and a recipe by Tim Love.
Date: January 1, 2004
Creator: Fox 4 KDFW
System: The UNT Digital Library
The Internet and College Students' Motivation to Vote (open access)

The Internet and College Students' Motivation to Vote

This article investigates the impact of the political information available on-line on college students’ motivation to vote. The results illustrate that not only politicians, but educators should be cognizant of this civic engagement process. Schools and teachers of all levels are one the front lines of the battle to create a more informed, more involved citizenry; higher education has a strong influence on motivation to vote.
Date: March 1, 2004
Creator: White, Amy E. & King, Kimi L.
System: The UNT Digital Library
Preface 2004 (open access)

Preface 2004

Introduction to the 2004 edition of The Eagle Feather.
Date: October 1, 2004
Creator: Cox, Gloria C. & Eve, Susan Brown
System: The UNT Digital Library
Insights into the Dynamic Response of Tunnels in Jointed Rocks (open access)

Insights into the Dynamic Response of Tunnels in Jointed Rocks

Tunnels in jointed rocks can be subjected to severe dynamic loads because of rock bursts, coal bumps, and large earthquakes. A series of 3-dimensional simulations was performed, based on discrete element analysis to gain insights into the parameters that influence the response of such tunnels. The simulations looked at the effect of joint set orientation, the effect of joint spacing, the effect of pulse shape for a given displacement, and the influence of using rigid versus deformable blocks in the analyses. The results of this modeling were also compared to field evidence of dynamic tunnel failures. This comparison reinforced the notion that 3-dimensional discrete element analysis can capture very well the kinematics of structures in jointed rock under dynamic loading.
Date: November 1, 2004
Creator: Heuze, F E
System: The UNT Digital Library
Toward understanding environmental effects in SDSS clusters (open access)

Toward understanding environmental effects in SDSS clusters

We find clusters and superclusters of galaxies using the Data Release 1 of the Sloan Digital Sky Survey. We determine the luminosity function of clusters and find that clusters in a high-density environment have a luminosity a factor of {approx}5 higher than in a low-density environment. We also study clusters and superclusters in numerical simulations. Simulated clusters in a high-density environment are also more massive than those in a low-density environment. Comparison of the density distribution at various epochs in simulations shows that in large low-density regions (voids) dynamical evolution is very slow and stops at an early epoch. In contrast, in large regions of higher density (superclusters) dynamical evolution starts early and continues until the present; here particles cluster early, and by merging of smaller groups very rich systems of galaxies form.
Date: November 1, 2004
Creator: Einasto, Jaan; Tago, E.; Einasto, M.; Saar, E.; Suhhonenko, I.; Heinamaki, P. et al.
System: The UNT Digital Library
Analysis and Comparison of Test Results from the Small Wind Research Turbine Test Project: Preprint (open access)

Analysis and Comparison of Test Results from the Small Wind Research Turbine Test Project: Preprint

Most small wind turbines furl (yaw or tilt out of the wind) as a means of limiting power and rotor speeds in high winds. The Small Wind Research Turbine (SWRT) testing project was initiated in 2003 with the goal of better characterizing both small wind turbine loads (including thrust) and dynamic behavior, specifically as they relate to furling. The main purpose of the testing was to produce high-quality data sets for model development and validation and to help the wind industry further their understanding of small wind turbine behavior. Testing was conducted on a modified Bergey Excel 10-kW wind turbine. A special shaft sensor was designed to measure shaft loads including thrust, torque, and shaft bending. Analysis of 10-minute mean data showed a strong correlation between furling and center of thrust location, as calculated from the shaft-bending and thrust measurements. Data were collected for three different turbine configurations that included a change in the lateral furling offset and the blades. An analysis of inflow conditions indicated that organized atmospheric turbulence had some impact on furling.
Date: November 1, 2004
Creator: Corbus, D. & Prascher, D.
System: The UNT Digital Library
Interconnection Testing of Distributed Resources: Preprint (open access)

Interconnection Testing of Distributed Resources: Preprint

With the publication of IEEE 1547-2003(TM) Standard for Interconnecting Distributed Resources With Electric Power Systems, the electric power industry has a need to develop tests and procedures to verify that interconnection equipment meets 1547 technical requirements. A new standard, IEEE P1547.1(TM), is being written to give detailed tests and procedures for confirming that equipment meets the interconnection requirements. The National Renewable Energy Laboratory has been validating test procedures being developed as part of IEEE P1547.1. As work progresses on the validation of those procedures, information and test reports are passed on to the working group of IEEE P1547.1 for future revisions.
Date: February 1, 2004
Creator: Kroposki, B.; Basso, T. & DeBlasio, R.
System: The UNT Digital Library
Diagnostic potential of cosmic-neutrino absorption spectroscopy (open access)

Diagnostic potential of cosmic-neutrino absorption spectroscopy

Annihilation of extremely energetic cosmic neutrinos on the relic-neutrino background can give rise to absorption lines at energies corresponding to formation of the electroweak gauge boson Z{sup 0}. The positions of the absorption dips are set by the masses of the relic neutrinos. Suitably intense sources of extremely energetic (10{sup 21} - 10{sup 25}-eV) cosmic neutrinos might therefore enable the determination of the absolute neutrino masses and the flavor composition of the mass eigenstates. Several factors--other than neutrino mass and composition--distort the absorption lines, however. We analyze the influence of the time-evolution of the relic-neutrino density and the consequences of neutrino decay. We consider the sensitivity of the lineshape to the age and character of extremely energetic neutrino sources, and to the thermal history of the Universe, reflected in the expansion rate. We take into account Fermi motion arising from the thermal distribution of the relic-neutrino gas. We also note the implications of Dirac vs. Majorana relics, and briefly consider unconventional neutrino histories. We ask what kinds of external information would enhance the potential of cosmic-neutrino absorption spectroscopy, and estimate the sensitivity required to make the technique a reality.
Date: December 1, 2004
Creator: Barenboim, Gabriela; U., /Valencia; Mena Requejo, Olga; Quigg, Chris & /Fermilab
System: The UNT Digital Library
The SAMGrid monitoring service and its integration with MonALISA (open access)

The SAMGrid monitoring service and its integration with MonALISA

The SAMGrid team is in the process of implementing a monitoring and information service, which fulfills several important roles in the operation of the SAMGrid system, and will replace the first generation of monitoring tools in the current deployments. The first generation tools are in general based on text log-files and represent solutions which are not scalable or maintainable. The roles of the monitoring and information service are: (1) providing diagnostics for troubleshooting the operation of SAMGrid services; (2) providing support for monitoring at the level of user jobs; (3) providing runtime support for local configuration and other information which currently must be stored centrally (thus moving the system toward greater autonomy for the SAMGrid station services, which include cache management and job management services); (4) providing intelligent collection of statistics in order to enable performance monitoring and tuning. The architecture of this service is quite flexible, permitting input from any instrumented SAMGrid application or service. It will allow multiple backend storage for archiving of (possibly) filtered monitoring events, as well as real time information displays and active notification service for alarm conditions. This service will be able to export, in a configurable manner, information to higher level Grid monitoring …
Date: December 1, 2004
Creator: Lyon, A.; Vokac, P.; Zimmler, M.; Baranovski, G.; Garzoglio, G.; Loebel-Carpenter, L. et al.
System: The UNT Digital Library
Redesign of the CKM RICH velocity spectrometers for use in a 1/4 GHz un separated beam (open access)

Redesign of the CKM RICH velocity spectrometers for use in a 1/4 GHz un separated beam

I report here a redesign of the CKM RICH velocity spectrometers for use in a 1/4 GHz unseparated beam adapted to the KTeV beam line and detector hall at Fermilab (P940). The redesigns reported here comprise modest modification to the original designs for CKM(E921) to accommodate the change in beam flux, momentum, and momentum bite of the primary beam. The ultimate performance of the velocity spectrometer systems, as quantified by the missing mass squared resolution for K{sup +} {yields} {pi}{sup +} x{sup 0}, remains largely unchanged from the original design.
Date: January 1, 2004
Creator: Cooper, Peter S. & Engelfried, Jurgen
System: The UNT Digital Library
Transforming the Market for Sustainable Design: Effective Public Policies and Strategies; Preprint (open access)

Transforming the Market for Sustainable Design: Effective Public Policies and Strategies; Preprint

The federal government strives to lead by example in energy and resource management and architectural design. This paper explores how public agencies are supporting that goal by using sustainable practices in the design and operation of their buildings. It presents some elements to consider in establishing a policy for sustainable design and a system for implementing that policy, including some of the most difficult implementation issues agencies have to face. The paper also highlights some of the strengths and weaknesses of federal, state, and local policies and practices governing the design of public buildings; two case studies provide examples. Different approaches are included to help agencies evaluate their effectiveness at various levels of government. And recommendations are made for agencies and others who are committed to sustainable design in both new construction and major renovations.
Date: May 1, 2004
Creator: Carlisle, N.; Glickman, J.; Brown, M.; Foster, M.; Bennett, A. K. & Sandler, K.
System: The UNT Digital Library
Measurement of orbitally excited D-mesons at CDF II (open access)

Measurement of orbitally excited D-mesons at CDF II

Results of the first measurement of {sup 3}P orbitally excited neutral D-meson states, D*{sub 2}{sup 0} and D{sub 1}{sup 0}, produced in hadron collisions at the Tevatron are presented. Using data from the displaced track trigger, CDF II collects a large sample of these states in decay modes D*{sup +} {pi}{sup -}, D{sup +} {pi}{sup -}. Masses and widths of both states have been measured with precision better than or comparable to that of the world average.
Date: December 1, 2004
Creator: Gorelov, Igor V.
System: The UNT Digital Library
X-Ray Line Measurements with High Efficiency Bragg Crystals (open access)

X-Ray Line Measurements with High Efficiency Bragg Crystals

We have studied the focusing properties of two highly oriented pyrolitic graphite (HOPG) spectrometers, which differ in the degree of the mosaic spread: ZYA with a low mosaic spread ({gamma}=0.4 degrees) and ZYH with a large mosaic spread ({gamma}=3.5 degrees). In order to assess the crystal performance for a variety of different experiments, various K{alpha} and K{beta} x-ray lines have been produced using a high-intensity ({approx}>10{sup 17} W/cm{sup 2}) short-pulse ({approx} 100 fs) laser beam focused onto Ti, V, Zn, and Cu foils. The measured spectral resolution of the HOPG crystals in both first and second order diffraction has been compared with theoretical predictions. Using known values for the peak reflectivity of HOPG crystals, we have also computed K{alpha} x-ray conversion efficiencies of Ti, V, Zn, and Cu. These results are important to estimate the optimal conditions under which different types of HOPG monochromators can be used for the detection of weak x-ray signals as the one encountered in x-ray Thomson/Compton scattering experiments.
Date: April 1, 2004
Creator: Pak, A; Gregori, G; Knight, J; Campbell, K; Landen, O & Glenzer, S
System: The UNT Digital Library
Evacuated-Tube Heat-Pipe Solar Collectors Applied to the Recirculation Loop in a Federal Building: Preprint (open access)

Evacuated-Tube Heat-Pipe Solar Collectors Applied to the Recirculation Loop in a Federal Building: Preprint

This paper describes the design, simulation, construction, and initial performance of a solar water heating system (a 360-tube evacuated-tube heat-pipe solar collector, 54 m2 in gross area, 36 m2 in net absorber area) installed at the top of the hot water recirculation loop in the Social Security Administration's Mid-Atlantic Center in Philadelphia. When solar energy is available, water returning to the hot water storage tank is heated by the solar array. This new approach, in contrast to the more conventional approach of preheating incoming water, is made possible by the thermal diode effect of heat pipes and low heat loss from evacuated-tube solar collectors. The simplicity of this approach and its low installation costs support the deployment of solar energy in existing commercial buildings, especially where the roof is some distance away from the water heating system, which is often in the basement. Initial performance measurements of the system are reported.
Date: June 1, 2004
Creator: Walker, A.; Mahjouri, F. & Stiteler, R.
System: The UNT Digital Library
Integrated Cabin and Fuel Cell System Thermal Management with a Metal Hydride Heat Pump (open access)

Integrated Cabin and Fuel Cell System Thermal Management with a Metal Hydride Heat Pump

Integrated approaches for the heating and cooling requirements of both the fuel cell (FC) stack and cabin environment are critical to fuel cell vehicle performance in terms of stack efficiency, fuel economy, and cost. An integrated FC system and cabin thermal management system would address the cabin cooling and heating requirements, control the temperature of the stack by mitigating the waste heat, and ideally capture the waste heat and use it for useful purposes. Current work at the National Renewable Energy Laboratory (NREL) details a conceptual design of a metal hydride heat pump (MHHP) for the fuel cell system and cabin thermal management.
Date: December 1, 2004
Creator: Hovland, V.
System: The UNT Digital Library
Future hadron physics facilities at Fermilab (open access)

Future hadron physics facilities at Fermilab

Fermilab's hadron physics research continues in all its accelerator-based programs. These efforts will be identified, and the optimization of the Fermilab schedules for physics will be described. In addition to the immediate plans, the Fermilab Long Range Plan will be cited, and the status and potential role of a new proton source, the Proton Driver, is described.
Date: December 1, 2004
Creator: Appel, Jeffrey A.
System: The UNT Digital Library
The CDF Central Analysis Farm (open access)

The CDF Central Analysis Farm

With Run II of the Fermilab Tevatron well underway, many computing challenges inherent to analyzing large volumes of data produced in particle physics research need to be met. We present the computing model within CDF designed to address the physics needs of the collaboration. Particular emphasis is placed on current development of a large O(1000) processor PC cluster at Fermilab serving as the Central Analysis Farm for CDF. Future plans leading toward distributed computing and GRID within CDF are also discussed.
Date: January 1, 2004
Creator: Kim, T. H.; /MIT; Neubauer, M.; /UC, San Diego; Sfiligoi, I.; /Frascati et al.
System: The UNT Digital Library
Morphology of Methane Hydrate Host Sediments. (open access)

Morphology of Methane Hydrate Host Sediments.

Results from simulated experiments in several laboratories show that host sediments influence hydrate formation in accord with known heterogeneity of host sediments at sites of gas hydrate occurrence (1). For example, in Mackenzie Delta, NWT Canada (Mallik 2L-38 well), coarser-grained units (pore-filling model) are found whereas in the Gulf of Mexico, the found hydrate samples do not appear to be lithologically controlled. We have initiated a systematic study of sediments, initially focusing on samples from various depths at a specific site, to establish a correlation with hydrate occurrence (or variations thereof) to establish differences in their microstructure, porosity, and other associated properties. The synchrotron computed microtomography (CMT) set-up at the X-27A tomography beam line at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory was used as a tool to study sediments from Blake Ridge at three sub bottom depths of 0.2, 50, and 667 meters. Results from the tomographic analysis of the deepest sample (667 m) are presented here to illustrate how tomography can be used to obtain new insights into the structures of methane hydrate host sediments. The investigation shows the internal grain/pore space resolution in the microstructure and a 3-D visualization of the connecting pathways obtained following …
Date: December 1, 2004
Creator: Jones, K. W.; Feng, H.; Tomov, S.; Winter, W. J.; Eaton, M. & Mahajan, D.
System: The UNT Digital Library
Production LHC HTS power lead test results (open access)

Production LHC HTS power lead test results

The Fermilab Magnet test facility has built and operated a test stand to characterize the performance of HTS power leads. We report here the results of production tests of 20 pairs of 7.5 kA HTS power leads manufactured by industry for installation in feed boxes for the LHC Interaction Region quadrupole strings. Included are discussions of the thermal, electrical, and quench characteristics under ''standard'' and ''extreme'' operating conditions, and the stability of performance across thermal cycles.
Date: October 1, 2004
Creator: Tartaglia, M. A.; Carcagno, R. H.; Feher, S.; Huang, Y.; Orris, D. F.; Pischalnikov, Y. et al.
System: The UNT Digital Library
OEDGE Modeling of {sup 13}C Deposition in the Inner Divertor of DIII-D (open access)

OEDGE Modeling of {sup 13}C Deposition in the Inner Divertor of DIII-D

Use of carbon in tokamaks leads to a major tritium retention issue due to co-deposition. To investigate this process a low power (no beams) L-mode experiment was performed on DIII-D in which {sup 13}CH{sub 4} was puffed into the main vessel through the toroidally-symmetric pumping plenum at the top of lower single-null discharges. Subsequently, the {sup 13}C content of tiles taken from the vessel wall was measured. The interpretive OEDGE code was used to model the results. It was found that the {sup 13}C deposition pattern is controlled by: (a) source strength of {sup 13}C{sup +}, (b) radial location of the {sup 13}C{sup +} source, (c) D{sub {perpendicular}}, (d) M{sub {parallel}}, the scrape-off layer parallel Mach number. Best agreement was found for (a) {approx}50% conversion efficiency {sup 13}CH{sub 4} {yields} {sup 13}C{sup +}, (b) {sup 13}C{sup +} source {approx}3.5 cm outboard of separatrix near {sup 13}CH{sub 4} injection location, (c)D{sub {perpendicular}} {approx} 0.3 m{sup 2}s{sup -1}, (d) M{sub {parallel}} {approx} 0.4 toward inside.
Date: December 1, 2004
Creator: Elder, J.; Stangeby, P.; Whyte, D.; Allen, S.; McLean, A.; Boedo, J. et al.
System: The UNT Digital Library
Lambdastation: a forwarding and admission control service to interface production network facilities with advanced research network paths (open access)

Lambdastation: a forwarding and admission control service to interface production network facilities with advanced research network paths

Over the past several years, there has been a great deal of research effort and funding put into the deployment of optical-based, advanced technology wide-area networks. Fermilab and CalTech have initiated a project to enable our production network facilities to exploit these advanced research network facilities. Our objective is to forward designated data transfers across these advanced wide area networks on a per-flow basis, making use our capacious production-use storage systems connected to the local campus network. To accomplish this, we intend to develop a dynamically provisioned forwarding service that would provide alternate path forwarding onto available wide area advanced research networks. The service would dynamically reconfigure forwarding of specific flows within our local production-use network facilities, as well as provide an interface to enable applications to utilize the service. We call this service LambdaStation. If one envisions wide area optical network paths as high bandwidth data railways, then LambdaStation would functionally be the railroad terminal that regulates which flows at the local site get directed onto the high bandwidth data railways. LambdaStation is a DOE-funded SciDac research project in its very early stage of development.
Date: December 1, 2004
Creator: DeMar, Philip & Petravick, Don
System: The UNT Digital Library
Superconducting multipole corrector magnet (open access)

Superconducting multipole corrector magnet

A novel concept of superconducting multipole corrector magnet is discussed. This magnet assembled from 12 identical racetrack type coils and can generate any combination of dipole, quadrupole and sextupole magnetic fields. The coil groups are powered from separate power supplies. In the case of normal dipole, quadrupole and sextupole fields the total field is symmetrical relatively the magnet median plane and there are only five powered separately coil groups. This type multipole corrector magnet was proposed for BTeV, Fermilab project and has following advantages: universal configuration, simple manufacturing and high mechanical stability. The results of magnetic design including the field quality and magnetic forces in comparison with known shell type superconducting correctors are presented.
Date: October 1, 2004
Creator: Kashikhin, Vladimir
System: The UNT Digital Library
Some phenomenology of intersecting D-brane models (open access)

Some phenomenology of intersecting D-brane models

We present some phenomenology of a new class of intersecting D-brane models. Soft SUSY breaking terms for these models are calculated in the complex structure (u)-moduli dominant SUSY breaking approach (in type IIA). In this case, the dependence of the soft terms on the Yukawas and Wilson lines drops out. These soft terms have a different pattern compared to the usual heterotic string models. Phenomenological implications for dark matter are discussed.
Date: November 1, 2004
Creator: Kane, Gordon L.; Kumar, Piyush; Lykken, Joseph D. & Wang, Ting T.
System: The UNT Digital Library
Towards CP-violation results from D0 (open access)

Towards CP-violation results from D0

We have made a preliminary study of a dimuon sample corresponding to 114 pb{sup -1} of data taken in Run II at the Tevatron. From this sample we have selected 157 {+-} 20 B{sub d} {yields} J/{psi}K{sub S}{sup 0} and 133 {+-} 17 B{sub s} {yields} J/{psi}{phi} decays. In a subset of the data we have measured the B{sup {+-}} lifetime in the J/{psi}K{sup {+-}} channel to be 1.76 {+-} 0.24 ps. We have implemented a jet-charge initial-flavor tag as well as a soft-muon tag, and we have measured the respective tagging powers to be (2.4 {+-} 1.7)% and (3.3 {+-} 1.8)%. Our conclusion from these studies is that we have made good progress towards understanding all ingredients required to make CP violation measurements in the B{sub d} and B{sub s} systems.
Date: January 1, 2004
Creator: Balm, P. & /NIKHEF, Amsterdam
System: The UNT Digital Library