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NOAA: Next Steps to Strengthen Its Acquisition Function (open access)

NOAA: Next Steps to Strengthen Its Acquisition Function

A letter report issued by the Government Accountability Office with an abstract that begins "The National Oceanic and Atmospheric Administration (NOAA) accounts for about half of the Department of Commerce's (Commerce) acquisition spending, over $851 million in fiscal year 2005 alone. In recent years however, NOAA has experienced instances of poor contract management. GAO was asked to determine if NOAA is positioned to effectively carry out its acquisition function. Specifically, GAO assessed the extent to which NOAA has structured an acquisition organization that provides appropriate oversight; established policies and processes that promote, among other things, a knowledge-based acquisition process for development and production of complex systems; and planned and managed its contracting workforce to address future retirement challenges."
Date: June 7, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Clean Water: Better Information and Targeted Prevention Efforts Could Enhance Spill Management in the St. Clair-Detroit River Corridor (open access)

Clean Water: Better Information and Targeted Prevention Efforts Could Enhance Spill Management in the St. Clair-Detroit River Corridor

A letter report issued by the Government Accountability Office with an abstract that begins "Spills of oil and hazardous substances in the St. Clair-Detroit River corridor have degraded this border area between the United States and Canada and are a potential threat to local drinking water supplies. Within the United States such spills are reported to the National Response Center (NRC), and in Canada to the Ontario Spills Action Centre. This report discusses (1) how many oil and hazardous substance spills greater than 50 gallons (or of an unknown volume) were reported in the corridor from 1994 to 2004, and how accurately reported spills reflect the extent of actual spills; (2) what processes are used to notify parties of spills, and if they contain explicit requirements for reporting times and spill magnitude; and (3) the extent of Environmental Protection Agency (EPA) and the Coast Guard's spill prevention efforts and enforcement activities in the corridor from 1994 to 2004."
Date: June 7, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Enhanced geothermal systems (EGS) using CO2 as working fluid - Anovelapproach for generating renewable energy with simultaneoussequestration of carbon (open access)

Enhanced geothermal systems (EGS) using CO2 as working fluid - Anovelapproach for generating renewable energy with simultaneoussequestration of carbon

Responding to the need to reduce atmospheric emissions of carbon dioxide, Donald Brown (2000) proposed a novel enhanced geothermal systems (EGS) concept that would use CO{sub 2} instead of water as heat transmission fluid, and would achieve geologic sequestration of CO{sub 2} as an ancillary benefit. Following up on his suggestion, we have evaluated thermophysical properties and performed numerical simulations to explore the fluid dynamics and heat transfer issues in an engineered geothermal reservoir that would be operated with CO{sub 2}. We find that CO{sub 2} is superior to water in its ability to mine heat from hot fractured rock. CO{sub 2} also has certain advantages with respect to wellbore hydraulics, where larger compressibility and expansivity as compared to water would increase buoyancy forces and would reduce the parasitic power consumption of the fluid circulation system. While the thermal and hydraulic aspects of a CO{sub 2}-EGS system look promising, major uncertainties remain with regard to chemical interactions between fluids and rocks. An EGS system running on CO{sub 2} has sufficiently attractive features to warrant further investigation.
Date: June 7, 2006
Creator: Pruess, Karsten
Object Type: Article
System: The UNT Digital Library
Noncommutative Inspired Black Holes in Extra Dimensions (open access)

Noncommutative Inspired Black Holes in Extra Dimensions

In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS assumed that this smearing was essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from {approx} 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the TeV-scale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We …
Date: June 7, 2006
Creator: Rizzo, Thomas G.
Object Type: Report
System: The UNT Digital Library
How Can We Test Seesaw Experimentally? (open access)

How Can We Test Seesaw Experimentally?

The seesaw mechanism for the small neutrino mass has been a popular paradigm, yet it has been believed that there is no way to test it experimentally. We present a conceivable outcome from future experiments that would convince us of the seesaw mechanism. It would involve a variety of data from LHC, ILC, cosmology, underground, and low-energy flavor violation experiments to establish the case.
Date: June 7, 2006
Creator: Buckley, Matthew R. & Murayama, Hitoshi
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 210, Ed. 1 Wednesday, June 7, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 210, Ed. 1 Wednesday, June 7, 2006

Free weekly newspaper that includes business and classified advertising.
Date: June 7, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 16, Ed. 1 Wednesday, June 7, 2006 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 16, Ed. 1 Wednesday, June 7, 2006

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: June 7, 2006
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
Payday Loans: Federal Regulatory Initiatives (open access)

Payday Loans: Federal Regulatory Initiatives

None
Date: June 7, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 209, Ed. 1 Wednesday, June 7, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 209, Ed. 1 Wednesday, June 7, 2006

Free weekly newspaper that includes business and classified advertising.
Date: June 7, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Silica Extraction at Mammoth Lakes, California (open access)

Silica Extraction at Mammoth Lakes, California

The purpose of this project is to develop a cost-effective method to extract marketable silica (SiO{sub 2}) from fluids at the Mammoth Lakes, California geothermal power plant. Silica provides an additional revenue source for the geothermal power industry and therefore lowers the costs of geothermal power production. The use of this type of ''solution mining'' to extract resources eliminates the need for acquiring these resources through energy intensive and environmentally damaging mining technologies. We have demonstrated that both precipitated and colloidal silica can be produced from the geothermal fluids at Mammoth Lakes by first concentrating the silica to over 600 ppm using reverse osmosis (RO). The RO permeate can be used in evaporative cooling at the plant; the RO concentrate is used for silica and potentially other resource extraction (Li, Cs, Rb). Preliminary results suggest that silica recovery at Mammoth Lakes could reduce the cost of geothermal electricity production by 1.0 cents/kWh.
Date: June 7, 2006
Creator: Bourcier, W; Ralph, W; Johnson, M; Bruton, C & Gutierrez, P
Object Type: Article
System: The UNT Digital Library
LLNL Capabilities in Underground Coal Gasification (open access)

LLNL Capabilities in Underground Coal Gasification

Underground coal gasification (UCG) has received renewed interest as a potential technology for producing hydrogen at a competitive price particularly in Europe and China. The Lawrence Livermore National Laboratory (LLNL) played a leading role in this field and continues to do so. It conducted UCG field tests in the nineteen-seventies and -eighties resulting in a number of publications culminating in a UCG model published in 1989. LLNL successfully employed the ''Controlled Retraction Injection Point'' (CRIP) method in some of the Rocky Mountain field tests near Hanna, Wyoming. This method, shown schematically in Fig.1, uses a horizontally-drilled lined injection well where the lining can be penetrated at different locations for injection of the O{sub 2}/steam mixture. The cavity in the coal seam therefore gets longer as the injection point is retracted as well as wider due to reaction of the coal wall with the hot gases. Rubble generated from the collapsing wall is an important mechanism studied by Britten and Thorsness.
Date: June 7, 2006
Creator: Friedmann, S J; Burton, E & Upadhye, R
Object Type: Report
System: The UNT Digital Library
A Family of Zinc Finger Proteins Is Required forChromosome-specific Pairing and Synapsis during Meiosis in C.elegans (open access)

A Family of Zinc Finger Proteins Is Required forChromosome-specific Pairing and Synapsis during Meiosis in C.elegans

Homologous chromosome pairing and synapsis are prerequisitefor accurate chromosome segregation during meiosis. Here, we show that afamily of four related C2H2 zinc-finger proteins plays a central role inthese events in C. elegans. These proteins are encoded within a tandemgene cluster. In addition to the X-specific HIM-8 protein, threeadditional paralogs collectively mediate the behavior of the fiveautosomes. Each chromosome relies on a specific member of the family topair and synapse with its homolog. These "ZIM" proteins concentrate atspecial regions called meiotic pairing centers on the correspondingchromosomes. These sites are dispersed along the nuclear envelope duringearly meiotic prophase, suggesting a role analogous to thetelomere-mediated meiotic bouquet in other organisms. To gain insightinto the evolution of these components, wecharacterized homologs in C.briggsae and C. remanei, which revealed changes in copy number of thisgene family within the nematode lineage.
Date: June 7, 2006
Creator: Phillips, Carolyn M. & Dernburg, Abby F.
Object Type: Article
System: The UNT Digital Library
Radiative cooling of laser ablated vapor plumes: experimental andtheoretical analyses (open access)

Radiative cooling of laser ablated vapor plumes: experimental andtheoretical analyses

None
Date: June 7, 2006
Creator: Wen, Sy-Bor; Mao, Xianglei; Grief, Ralph & Russo, Richard E.
Object Type: Article
System: The UNT Digital Library
Integrated modeling and field study of potential mechanisms forinduced seismicity at The Geysers Goethermal Field, California (open access)

Integrated modeling and field study of potential mechanisms forinduced seismicity at The Geysers Goethermal Field, California

In this paper, we present progress made in a study aimed atincreasing the understanding of the relative contributions of differentmechanisms that may be causing the seismicity occurring at The Geysersgeothermal field, California. The approach we take is to integrate: (1)coupled reservoir geomechanical numerical modeling, (2) data fromrecently upgraded and expanded NCPA/Calpine/LBNL seismic arrays, and (3)tens of years of archival InSAR data from monthly satellite passes. Wehave conducted a coupled reservoir geomechanical analysis to studypotential mechanisms induced by steam production. Our simulation resultscorroborate co-locations of hypocenter field observations of inducedseismicity and their correlation with steam production as reported in theliterature. Seismic and InSAR data are being collected and processed foruse in constraining the coupled reservoir geomechanicalmodel.
Date: June 7, 2006
Creator: Rutqvist, Jonny; Majer, Ernie; Oldenburg, Curt; Peterson, John & Vasco, Don
Object Type: Article
System: The UNT Digital Library
Longitudinal Coherence Preservation and Chirp Evolution in a High Gain Laser Seeded Free Electron Laser Amplifier (open access)

Longitudinal Coherence Preservation and Chirp Evolution in a High Gain Laser Seeded Free Electron Laser Amplifier

In this letter we examine the start-up of a high gain free electron laser in which a frequency-chirped coherent seed laser pulse interacts with a relativistic electron beam. A Green function formalism is used to evaluate the initial value problem. We have fully characterized the startup and evolution through the exponential growth regime. We obtain explicit expressions for the pulse duration, bandwidth and chirp of the amplified light and show that the FEL light remains fully longitudinally coherent.
Date: June 7, 2006
Creator: Murphy, J. B.; Wu, Juhao; Wang, X. J. & Watanabe, T.
Object Type: Report
System: The UNT Digital Library
Rare Hadronic B Decays (open access)

Rare Hadronic B Decays

Rare hadronic B-meson decays allow us to study CP violation. The class of B-decays final states containing two vector mesons provides a rich set of angular correlation observables to study. This article reviews some of the recent experimental results from the BABAR and Belle collaborations.
Date: June 7, 2006
Creator: Bevan, A.J.
Object Type: Article
System: The UNT Digital Library
Shock Desensitization Effect in the STANAG 4363 Confined Explosive Component Water Gap Test (open access)

Shock Desensitization Effect in the STANAG 4363 Confined Explosive Component Water Gap Test

The Explosive Component Water Gap Test (ECWGT) in the Stanag 4363 has been recently investigated to assess the shock sensitivity of lead and booster components having a diameter less than 5 mm. For that purpose, Pentaerythritol Tetranitrate (PETN) based pellets having a height and diameter of 3 mm have been confined by a steel annulus of wall thickness 1-3.5 mm and with the same height as the pellet. 1-mm wall thickness makes the component more sensitive (larger gap). As the wall thickness is increased to 2-mm, the gap increases a lesser amount, but when the wall thickness is increased to 3.5-mm a decrease in sensitivity is observed (smaller gap). This decrease of the water gap has been reproduced experimentally by many nations. Numerical simulations using Ignition and Growth model have been performed in this paper and have reproduced the experimental results for the steel confinement up to 2 mm thick and aluminum confinement. A stronger re-shock following the first input shock from the water is focusing on the axis due to the confinement. The double shock configuration is well-known to lead in some cases to shock desensitization.
Date: June 7, 2006
Creator: Lefrancois, A. S.; Lee, R. S. & Tarver, C. M.
Object Type: Report
System: The UNT Digital Library
Calculation of the Beam Field in the LCLS Bunch Length Monitor (open access)

Calculation of the Beam Field in the LCLS Bunch Length Monitor

Maintaining a stable bunch length and peak current is a critical step for the reliable operation of a SASE based x-ray source. In the LCLS, relative bunch length monitors (BLM) right after both bunch compressors are proposed based on the coherent radiation generated by the short electron bunch. Due to its diagnostic setup, the standard far field synchrotron radiation formula and well-developed numerical codes do not apply for the analysis of the BLM performance. In this paper, we develop a calculation procedure to take into account the near field effect, the effect of a short bending magnet, and the diffraction effect of the radiation transport optics. We find the frequency response of the BLM after the first LCLS bunch compressor and discuss its expected performance.
Date: June 7, 2006
Creator: Stupakov, G.; Ding, Y. & Huang, Z.
Object Type: Report
System: The UNT Digital Library
Seminole Sentinel (Seminole, Tex.), Vol. 97, No. 69, Ed. 1 Wednesday, June 7, 2006 (open access)

Seminole Sentinel (Seminole, Tex.), Vol. 97, No. 69, Ed. 1 Wednesday, June 7, 2006

Semiweekly newspaper from Seminole, Texas that includes local, state, and national news along with extensive advertising.
Date: June 7, 2006
Creator: Wright, Dustin
Object Type: Newspaper
System: The Portal to Texas History
[UNT Buddy System application, 2006] (open access)

[UNT Buddy System application, 2006]

A form that was used to apply to the Buddy System Mentorship Program during the 2006 spring semester. It asks for students' information and lists contact information for the UNT Multicultural Center at the top.
Date: June 7, 2006
Creator: University of North Texas. Multicultural Center.
Object Type: Text
System: The UNT Digital Library
Yoakum Herald-Times (Yoakum, Tex.), Vol. 114, No. 23, Ed. 1 Wednesday, June 7, 2006 (open access)

Yoakum Herald-Times (Yoakum, Tex.), Vol. 114, No. 23, Ed. 1 Wednesday, June 7, 2006

Weekly newspaper from Yoakum, Texas that includes local, state, and national news along with advertising.
Date: June 7, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Llano News (Llano, Tex.), Vol. 118, No. 36, Ed. 1 Wednesday, June 7, 2006 (open access)

The Llano News (Llano, Tex.), Vol. 118, No. 36, Ed. 1 Wednesday, June 7, 2006

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: June 7, 2006
Creator: Stephenson, Jimmy
Object Type: Newspaper
System: The Portal to Texas History
[Funeral Program for James Washington, June 7, 2006] (open access)

[Funeral Program for James Washington, June 7, 2006]

Funeral program for Brother James Washington, born January 9, 1928 and died June 3, 2006. The funeral was held June 7, 2006 at the Greater Corinth Baptist Church, officiated by Dr. Carl Johnson. Funeral arrangements were made through the Lewis Funeral Home, and he was buried in Fort Sam Houston National Cemetery near San Antonio, Texas.
Date: June 7, 2006
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
AIDS: The Ryan White CARE Act (open access)

AIDS: The Ryan White CARE Act

This report discusses the Ryan White Comprehensive AIDS Resources Emergency (CARE) Act, which makes federal funds available to metropolitan areas and states to assist in health care costs and support services for individuals and families affected by the human immunodeficiency virus (HIV) or acquired immune deficiency syndrome (AIDS). This report discusses related legislation and appropriations.
Date: June 7, 2006
Creator: Johnson, Judith A. & Morgan, Paulette C.
Object Type: Report
System: The UNT Digital Library