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Making it Work, Making it Fun: Metadata in Action

This presentation discusses metadata and how to ensure quality. It illustrates how the University of North Texas (UNT) utilizes a metadata analysis tool and a metadata template creator.
Date: June 1, 2007
Creator: Belden, Dreanna
Object Type: Presentation
System: The UNT Digital Library
Wildland Fire Management: Lack of Clear Goals or a Strategy Hinders Federal Agencies' Efforts to Contain the Costs of Fighting Fires (open access)

Wildland Fire Management: Lack of Clear Goals or a Strategy Hinders Federal Agencies' Efforts to Contain the Costs of Fighting Fires

A letter report issued by the Government Accountability Office with an abstract that begins "Annual appropriations to prepare for and respond to wildland fires have increased substantially over the past decade, in recent years totaling about $3 billion. The Forest Service within the Department of Agriculture and four agencies within the Department of the Interior (Interior) are responsible for responding to wildland fires on federal lands. GAO determined what steps federal agencies have taken, in response to findings from previous studies, to (1) address key operational areas that could help contain the costs of preparing for and responding to wildland fires and (2) improve their management of their cost-containment efforts. To address these objectives, GAO reviewed previous cost-containment studies and other agency documents and interviewed agency officials."
Date: June 1, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Addendum to the Closure Report for Corrective Action Unit 92: Area 6 Decon Pond Facility, Nevada Test Site, Nevada (open access)

Addendum to the Closure Report for Corrective Action Unit 92: Area 6 Decon Pond Facility, Nevada Test Site, Nevada

The following is an addendum to the 'Closure Report for Corrective Action Unit 92: Area 6 Decontamination Pond, Nevada Test Site, Nevada', DOE/NV/11718--306, dated April 1999. This addendum includes Use Restriction Information forms and survey maps for CAS 06-04-01, Decon Pad Oil/Water Separator, and CAS 06-05-02, Decontamination Pond (RCRA), that were inadvertently left out of the Closure Report when it was published as a final document.
Date: June 1, 2007
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Electron cooling rates characterization at Fermilab's Recycler (open access)

Electron cooling rates characterization at Fermilab's Recycler

A 0.1 A, 4.3 MeV DC electron beam is routinely used to cool 8 GeV antiprotons in Fermilab's Recycler storage ring [1]. The primary function of the electron cooler is to increase the longitudinal phase-space density of the antiprotons for storing and preparing high-density bunches for injection into the Tevatron. The longitudinal cooling rate is found to significantly depend on the transverse emittance of the antiproton beam. The paper presents the measured rates and compares them with calculations based on drag force data.
Date: June 1, 2007
Creator: Prost, Lionel R. & Shemyakin, A.
Object Type: Article
System: The UNT Digital Library
Fabrication of a Short-Period Nb3Sn Superconducting Undulator (open access)

Fabrication of a Short-Period Nb3Sn Superconducting Undulator

Lawrence Berkeley National Laboratory develops high-field Nb{sub 3}Sn magnets for HEP applications. In the past few years, this experience has been extended to the design and fabrication of undulator magnets. Some undulator applications require devices that can operate in the presence of a heat load from a beam. The use of Nb{sub 3}Sn permits operation of a device at both a marginally higher temperature (5-8K) and a higher J{sub c}, compared to NbTi devices, without requiring a larger magnetic gap. A half-undulator device consisting of 6 periods (12 coil packs) of 14.5 mm period was designed, wound, reacted, potted and tested. It reached the short sample current limit of 717A in 4 quenches. The non-Cu Jc of the strand was over 7,600 A/mm{sup 2} and the Cu current density at quench was over 8,000 A/mm{sup 2}. Magnetic field models show that if a complete device was fabricated with the same parameters one could obtain beam fields of 1.1 T and 1.6 T for pole gaps of 8 mm and 6 mm, respectively.
Date: June 1, 2007
Creator: Dietderich, Daniel; Dietderich, Daniel; Godeke, Arno; Prestemon, Soren; Pipersky, Paul T.; Liggins, Nate L. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Flow Phenomena in a VHTR Lower Plenum Model (open access)

Measurement of Flow Phenomena in a VHTR Lower Plenum Model

Mean velocity and turbulence data that measure turbulent flow phenomena in an approximately 1:7 scale model of a region of the lower plenum of a typical prismatic gas-cooled reactor are presented as a follow-up to summaries presented at the 2006 Annual Meeting and the 2006 Winter Meeting. The experiments were designed to develop benchmark databases to support the first Standard Problem endorsed by the Generation IV International Forum to validate the heat transfer and fluid flow software that will be used to study the behavior of the VHTR system.
Date: June 1, 2007
Creator: Jr., Hugh M. McIlroy; McEligot, Donald M. & Pink, Robert J.
Object Type: Article
System: The UNT Digital Library
Optimization of the Helical Orbits in the Tevatron (open access)

Optimization of the Helical Orbits in the Tevatron

To avoid multiple head-on collisions the proton and antiproton beams in the Tevatron move along separate helical orbits created by 7 horizontal and 8 vertical electrostatic separators. Still the residual long-range beam-beam interactions can adversely affect particle motion at all stages from injection to collision. With increased intensity of the beams it became necessary to modify the orbits in order to mitigate the beam-beam effect on both antiprotons and protons. This report summarizes the work done on optimization of the Tevatron helical orbits, outlines the applied criteria and presents the achieved results.
Date: June 1, 2007
Creator: Alexahin, Y.
Object Type: Article
System: The UNT Digital Library
Demonstration of Femtosecond-Phase Stabilization in 2 km OpticalFiber (open access)

Demonstration of Femtosecond-Phase Stabilization in 2 km OpticalFiber

Long-term phase drifts of less than a femtosecond per hour have been demonstrated in a 2 km length of single-mode optical fiber, stabilized interferometrically at 1530 nm. Recent improvements include a wide-band phase detector that reduces the possibility of fringe jumping due to fast external perturbations of the fiber and locking of the master CW laser wavelength to an atomic absorption line. Mode-locked lasers may be synchronized using two wavelengths of the comb, multiplexed over one fiber, each wavelength individually interferometrically stabilized.
Date: June 1, 2007
Creator: Staples, J. W.; Wilcox, R. & Byrd, J. M.
Object Type: Article
System: The UNT Digital Library
Descriptive Model of Generic WAMS (open access)

Descriptive Model of Generic WAMS

The Department of Energy’s (DOE) Transmission Reliability Program is supporting the research, deployment, and demonstration of various wide area measurement system (WAMS) technologies to enhance the reliability of the Nation’s electrical power grid. Pacific Northwest National Laboratory (PNNL) was tasked by the DOE National SCADA Test Bed Program to conduct a study of WAMS security. This report represents achievement of the milestone to develop a generic WAMS model description that will provide a basis for the security analysis planned in the next phase of this study.
Date: June 1, 2007
Creator: Hauer, John F. & DeSteese, John G.
Object Type: Report
System: The UNT Digital Library
NIF: A Path to Fusion Energy (open access)

NIF: A Path to Fusion Energy

Fusion energy has long been considered a promising, clean, nearly inexhaustible source of energy. Power production by fusion micro-explosions of inertial confinement fusion (ICF) targets has been a long-term research goal since the invention of the first laser in 1960. The National Ignition Facility (NIF) is poised to take the next important step in the journey by beginning experiments researching ICF ignition. Ignition on NIF will be the culmination of over thirty years of ICF research on high-powered laser systems such as the Nova laser at Lawrence Livermore National Laboratory (LLNL) and the OMEGA laser at the University of Rochester, as well as smaller systems around the world. NIF is a 192-beam Nd-glass laser facility at LLNL that is more than 90% complete. The first cluster of 48 beams is operational in the laser bay, the second cluster is now being commissioned, and the beam path to the target chamber is being installed. The Project will be completed in 2009, and ignition experiments will start in 2010. When completed, NIF will produce up to 1.8 MJ of 0.35-{micro}m light in highly shaped pulses required for ignition. It will have beam stability and control to higher precision than any other laser …
Date: June 1, 2007
Creator: Moses, Edward
Object Type: Article
System: The UNT Digital Library
An Overview of Current and Past W-UO[2] CERMET Fuel Fabrication Technology (open access)

An Overview of Current and Past W-UO[2] CERMET Fuel Fabrication Technology

Studies dating back to the late 1940s performed by a number of different organizations and laboratories have established the major advantages of Nuclear Thermal Propulsion (NTP) systems, particularly for manned missions. A number of NTP projects have been initiated since this time; none have had any sustained fuel development work that appreciably contributed to fuel fabrication or performance data from this era. As interest in these missions returns and previous space nuclear power researchers begin to retire, fuel fabrication technologies must be revisited, so that established technologies can be transferred to young researchers seamlessly and updated, more advanced processes can be employed to develop successful NTP fuels. CERMET fuels, specifically W-UO2, are of particular interest to the next generation NTP plans since these fuels have shown significant advantages over other fuel types, such as relatively high burnup, no significant failures under severe transient conditions, capability of accommodating a large fission product inventory during irradiation and compatibility with flowing hot hydrogen. Examples of previous fabrication routes involved with CERMET fuels include hot isostatic pressing (HIPing) and press and sinter, whereas newer technologies, such as spark plasma sintering, combustion synthesis and microsphere fabrication might be well suited to produce high quality, effective …
Date: June 1, 2007
Creator: Burkes, Douglas E.; Wachs, Daniel M.; Werner, James E. & Howe, Steven D.
Object Type: Article
System: The UNT Digital Library
Experimental Demonstration of Beam-Beam Compensation by Tevatron Electron Lenses and Prospects for the LHC (open access)

Experimental Demonstration of Beam-Beam Compensation by Tevatron Electron Lenses and Prospects for the LHC

Contains the observations of the beam-beam phenomena in the Tevatron and results of relevant beam studies.
Date: June 1, 2007
Creator: Shiltsev, V.; Alexahin, Y.; Kamerdzhiev, V.; Kuznetsov, G.; Zhang, X.L. & Bishofberger, K.
Object Type: Article
System: The UNT Digital Library
Development Of An Agroforestry Sequestration Project In KhammamDistrict Of India (open access)

Development Of An Agroforestry Sequestration Project In KhammamDistrict Of India

Large potential for agroforestry as a mitigation option hasgiven rise to scientific and policy questions. This paper addressesmethodological issues in estimating carbon sequestration potential,baseline determination, additionality and leakage in Khammam district,Andhra Pradesh, southern part of India. Technical potential forafforestation was determined considering the various landuse options. Forestimating the technical potential, culturable wastelands, fallow andmarginal croplands were considered for Eucalyptus clonal plantations.Field studies for aboveground and below ground biomass, woody litter andsoil organic carbon for baseline and project scenario were conducted toestimate the carbon sequestration potential. The baseline carbon stockwas estimated to be 45.33 tC/ha. The additional carbon sequestrationpotential under the project scenario for 30 years is estimated to be12.82 tC/ha/year inclusive of harvest regimes and carbon emissions due tobiomass burning and fertilizer application. The project scenario thoughhas a higher benefit cost ratio compared to baseline scenario, initialinvestment cost is high. Investment barrier exists for adoptingagroforestry in thedistrict.
Date: June 1, 2007
Creator: Sudha, P.; Ramprasad, V.; Nagendra, M.D.V.; Kulkarni, H.D. & Ravindranath, N.H.
Object Type: Article
System: The UNT Digital Library
Precision measurement of a particle mass at the linear collider (open access)

Precision measurement of a particle mass at the linear collider

Precision measurement of the stop mass at the ILC is done in a method based on cross-sections measurements at two different center-of-mass energies. This allows to minimize both the statistical and systematic errors. In the framework of the MSSM, a light stop, compatible with electro-weak baryogenesis, is studied in its decay into a charm jet and neutralino, the Lightest Supersymmetric Particle (LSP), as a candidate of dark matter. This takes place for a small stop-neutralino mass difference.
Date: June 1, 2007
Creator: Milstene, C.; Freitas, A.; Schmitt, M. & Sopczak, A.
Object Type: Article
System: The UNT Digital Library
Improving Energy Efficiency of Compressed Air System Based onSystem Audit (open access)

Improving Energy Efficiency of Compressed Air System Based onSystem Audit

Industrial electric motor systems consume more than 600billion kWh annually, accounting for more than 50 percent of China selectricity use. The International Energy Agency estimates thatoptimizing motor systems results in an improvement of 20-25 percent,which is well-supported by experience in both the U.S. and China.Compressed air systems in China use 9.4 percent of all electricity.Compressed air use in China is growing rapidly, as new industrial plantsare built and the production processes of existing plants expand andchange. Most of these systems, whether existing or new, are not optimizedfor energy efficiency. This paper will present a practitioner'sperspective on theemergence of compressed air auditing services inChina, specifically as it pertains to Shanghai and surrounding areas.Both the methodology used and the market development of these compressedair system services will be addressed. Finally, the potential for energysaving opportunities will be described based on highlights from over 50compressed air system energy audits completed by Shanghai EnergyConservation Service Center, both during the United Nations IndustrialDevelopment Organization (UNIDO) China Motor System Energy ConservationProgram, and after this training program was completed.
Date: June 1, 2007
Creator: Shanghai, Hongbo Qin & McKane, Aimee
Object Type: Article
System: The UNT Digital Library
SGP Cloud and Land Surface Interaction Campaign (CLASIC): Measurement Platforms (open access)

SGP Cloud and Land Surface Interaction Campaign (CLASIC): Measurement Platforms

The Cloud and Land Surface Interaction Campaign (CLASIC) will be conducted from June 8 to June 30, 2007, at the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site. Data will be collected using eight aircraft equipped with a variety of specialized sensors, four specially instrumented surface sites, and two prototype surface radar systems. The architecture of CLASIC includes a high-altitude surveillance aircraft and enhanced vertical thermodynamic and wind profile measurements that will characterize the synoptic scale structure of the clouds and the land surface within the ACRF SGP site. Mesoscale and microscale structures will be sampled with a variety of aircraft, surface, and radar observations. An overview of the measurement platforms that will be used during the CLASIC are described in this report. The coordination of measurements, especially as it relates to aircraft flight plans, will be discussed in the CLASIC Implementation Plan.
Date: June 1, 2007
Creator: Miller, M. A.; Avissar, R.; Berg, L. K.; Edgerton, S. A.; Fischer, M. L.; Jackson, T. J. et al.
Object Type: Report
System: The UNT Digital Library
Search for new physics coupling to the z boson (open access)

Search for new physics coupling to the z boson

We present the results of two searches for new particles that couple Z bosons in p{bar p} collisions at {radical}s = 1.96 TeV using the Collider Detector at Fermilab (CDF). In the first, we search for a long-lived parent of the Z boson using a data sample with a luminosity of 163 pb{sup -1}. Finding no significant excess above background, we set a limit on a fourth generation model as a function of mass and lifetime. In the second, we search for a particle that decays to a Z boson in conjunction with jets using a data sample with a luminosity of 1.06 fb{sup -1}. Finding no significant excess above background, we set a limit on a fourth generation model as a function of mass.
Date: June 1, 2007
Creator: Scott, Adam Liddle
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Design of Nb3Sn Coils for LARP Long Magnets (open access)

Design of Nb3Sn Coils for LARP Long Magnets

The LHC Accelerator Research Program (LARP) has a primary goal to develop, assemble, and test full size Nb{sub 3}Sn quadrupole magnet models for a luminosity upgrade of the Large Hadron Collider (LHC). A major milestone in this development is to assemble and test, by the end of 2009, two 4 m-long quadrupole cold masses, which will be the first Nb{sub 3}Sn accelerator magnet models approaching the length of real accelerator magnets. The design is based on the LARP Technological Quadrupoles (TQ), under development at FNAL and LBNL, with gradient higher than 200 T/m and aperture of 90 mm. The mechanical design will be chosen between two designs presently explored for the TQs: traditional collars and Al-shell based design (preloaded by bladders and keys). The fabrication of the first long quadrupole model is expected to start in the last quarter of 2007. Meanwhile the fabrication of 4 m-long racetrack coils started this year at BNL. These coils will be tested in an Al-shell based supporting structure developed at LBNL. Several challenges have to be addressed for the successful fabrication of long Nb{sub 3}Sn coils. This paper presents these challenges with comments and solutions adopted or under study for these magnets. The …
Date: June 1, 2007
Creator: Ferracin, Paolo; Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R. et al.
Object Type: Article
System: The UNT Digital Library
OTR imaging of intense 120 GeV protons in the NuMI beamline at FNAL (open access)

OTR imaging of intense 120 GeV protons in the NuMI beamline at FNAL

None
Date: June 1, 2007
Creator: Scarpine, V. E.; Tassotto, G.R. & Lumpkin, A. H.
Object Type: Article
System: The UNT Digital Library
Metal particles produced by laser ablation for ICP-MSmeasurements (open access)

Metal particles produced by laser ablation for ICP-MSmeasurements

Pulsed laser ablation (266nm) was used to generate metal particles of Zn and Al alloys using femtosecond (150 fs) and nanosecond (4 ns) laser pulses with identical fluences of 50 J cm{sup -2}. Characterization of particles and correlation with Inductively Coupled Plasma Mass Spectrometer (ICP-MS) performance was investigated. Particles produced by nanosecond laser ablation were mainly primary particles with irregular shape and hard agglomerates (without internal voids). Particles produced by femtosecond laser ablation consisted of spherical primary particles and soft agglomerates formed from numerous small particles. Examination of the craters by white light interferometric microscopy showed that there is a rim of material surrounding the craters formed after nanosecond laser ablation. The determination of the crater volume by white light interferometric microscopy, considering the rim of material surrounding ablation craters, revealed that the volume ratio (fs/ns) of the craters on the selected samples was approximately 9 (Zn), 7 (NIST627 alloy) and 5 (NIST1711 alloy) times more ablated mass with femtosecond pulsed ablation compared to nanosecond pulsed ablation. In addition, an increase of Al concentration from 0 to 5% in Zn base alloys caused a large increase in the diameter of the particles, up to 65% while using nanosecond laser pulses. …
Date: June 1, 2007
Creator: Gonzalez, Jhanis J.; Liu, Chunyi; Wen, Sy-Bor; Mao, Xianglei & Russo, Richard E.
Object Type: Article
System: The UNT Digital Library
Conceptual design of an L-band recirculating superconducting traveling wave accelerating structure for ILC (open access)

Conceptual design of an L-band recirculating superconducting traveling wave accelerating structure for ILC

With this paper, we propose the conceptual design of a traveling wave accelerating structure for a superconducting accelerator. The overall goal is to study a traveling wave (TW) superconducting (SC) accelerating structure for ILC that allows an increased accelerating gradient and, therefore reduction of the length of the collider. The conceptual studies were performed in order to optimize the acceleration structure design by minimizing the surface fields inside the cavity of the structure, to make the design compatible with existing technology, and to determine the maximum achievable gain in the accelerating gradient. The proposed solution considers RF feedback system redirecting the accelerating wave that passed through the superconducting traveling wave acceleration (STWA) section back to the input of the accelerating structure. The STWA structure has more cells per unit length than a TESLA structure but provides an accelerating gradient higher than a TESLA structure, consequently reducing the cost. In this paper, the STWA cell shape optimization, coupler cell design and feedback waveguide solution are considered. We also discuss the field flatness in the superconducting TW structure, the HOM modes and multipactor performance have been studied as well. The proposed TW structure design gives an overall 46% gain over the SW …
Date: June 1, 2007
Creator: Avrakhov, P.; Kanareykin, A.; Liu, Z.; Kazakov, S.; /KEK, Tsukuba; Solyak, N. et al.
Object Type: Article
System: The UNT Digital Library
Optical Network Testbeds Workshop (open access)

Optical Network Testbeds Workshop

This is the summary report of the third annual Optical Networking Testbed Workshop (ONT3), which brought together leading members of the international advanced research community to address major challenges in creating next generation communication services and technologies. Networking research and development (R&D) communities throughout the world continue to discover new methods and technologies that are enabling breakthroughs in advanced communications. These discoveries are keystones for building the foundation of the future economy, which requires the sophisticated management of extremely large qualities of digital information through high performance communications. This innovation is made possible by basic research and experiments within laboratories and on specialized testbeds. Initial network research and development initiatives are driven by diverse motives, including attempts to solve existing complex problems, the desire to create powerful new technologies that do not exist using traditional methods, and the need to create tools to address specific challenges, including those mandated by large scale science or government agency mission agendas. Many new discoveries related to communications technologies transition to wide-spread deployment through standards organizations and commercialization. These transition paths allow for new communications capabilities that drive many sectors of the digital economy. In the last few years, networking R&D has increasingly focused …
Date: June 1, 2007
Creator: Mambretti, Joe
Object Type: Text
System: The UNT Digital Library
Assessment Of Carbon Leakage In Multiple Carbon-Sink Projects: ACase Study In Jambi Province, Indonesia (open access)

Assessment Of Carbon Leakage In Multiple Carbon-Sink Projects: ACase Study In Jambi Province, Indonesia

Rehabilitation of degraded forest land throughimplementation of carbon sink projects can increase terrestrial carbonstock. However, carbon emissions outside the project boundary, which iscommonly referred to as leakage, may reduce or negate the sequestrationbenefits. This study assessed leakage from carbon sink projects thatcould potentially be implemented in the study area comprised of elevensub-districts in the Batanghari District, Jambi Province, Sumatra,Indonesia. The study estimates the probability of a given land use/coverbeing converted into other uses/cover, by applying a logit model. Thepredictor variables were: proximity to the center of the land use area,distance to transportation channel (road or river), area of agriculturalland, unemployment (number of job seekers), job opportunities, populationdensity and income. Leakage was estimated by analyzing with and withoutcarbon sink projects scenarios. Most of the predictors were estimated asbeing significant in their contribution to land use cover change. Theresults of the analysis show that leakage in the study area can be largeenough to more than offset the project's carbon sequestration benefitsduring the period 2002-2012. However, leakage results are very sensitiveto changes of carbon density of the land uses in the study area. Byreducing C-density of lowland and hill forest by about 10 percent for thebaseline scenario, the leakage becomes positive. Further data …
Date: June 1, 2007
Creator: Boer, Rizaldi; Wasrin, Upik R.; Hendri, Perdinan; Dasanto,Bambang D.; Makundi, Willy; Hero, Julius et al.
Object Type: Article
System: The UNT Digital Library
Controls, LLRF, and instrumentation systems for ILC test facilities at Fermilab (open access)

Controls, LLRF, and instrumentation systems for ILC test facilities at Fermilab

The major controls and instrumentation systems for the ILC test areas and the NML test accelerator at Fermilab are discussed. The test areas include 3 separate areas for Vertical Superconducting RF Cavity Testing, Horizontal Cavity Testing, and NML RF and beam test area. A common control infrastructure for the test areas including a controls framework, electronic logbook and cavity database will be provided, while supporting components supplied by collaborators with diverse areas of expertise (EPICS, DOOCS, LabVIEW, and Matlab). The discussions on the instrumentation systems are focused on overview and requirements.
Date: June 1, 2007
Creator: Chase, B.; Votava, M.; Wendt, M. & /Fermilab
Object Type: Article
System: The UNT Digital Library