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Coastal Barrier Resources System: Status of Development That Has Occurred and Financial Assistance Provided by Federal Agencies

Description: A letter report issued by the Government Accountability Office with an abstract that begins "In 1982, Congress enacted the Coastal Barrier Resources Act. The Coastal Barrier Resources Act, as amended (CBRA), designates 585 units of undeveloped coastal lands and aquatic habitat as the John H. Chafee Coastal Barrier Resources System (CBRS). CBRA prohibits most federal expenditures and assistance within the system that could encourage development, but it allows federal agencies to provide some typ… more
Date: March 19, 2007
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of the Richtmyer-Meshkov instability

Description: The present research program is centered on the experimental and numerical study of the hydrodynamics of shock-accelerated spherical density inhomogeneities. These flows are part of a broader category of shock-induced mixing flows that play a critical role in the implosion of D-T pellets in laser-driven ICF experiments. For the past year, our work has consisted of both experimental and numerical activities which were presented at two conferences and resulted in the publication of one journal ar… more
Date: March 19, 2007
Creator: Bonazza, Riccardo; Anderson, Mark & Oakley, Jason
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Kahler stabilized, modular invariant heterotic string models

Description: We review the theory and phenomenology of effective supergravity theories based on orbifold compactifications of the weakly-coupled heterotic string. In particular, we consider theories in which the four-dimensional theory displays target space modular invariance and where the dilatonic mode undergoes Kahler stabilization. A self-contained exposition of effective Lagrangian approaches to gaugino condensation and heterotic string theory is presented, leading to the development of the models of B… more
Date: March 19, 2007
Creator: Gaillard, Mary K.; Gaillard, Mary K. & Nelson, Brent D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Hierarchical Build-Up of Massive Galaxies And the Intracluster Light Since z=1

Description: We use a set of simulation-based models for the dissipationless evolution of galaxies since z = 1 to constrain the fate of accreted satellites embedded in dark matter subhalos. These models assign stellar mass to dark matter halos at z = 1 by relating the observed galaxy stellar mass function (GSMF) to the halo+subhalo mass function monotonically. The evolution of the stellar mass content is then followed using halo merger trees extracted from N-body simulations. Our models are differentiated o… more
Date: March 19, 2007
Creator: Conroy, Charlie; Wechsler, Risa H. & Kravtsov, Andrey V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of a Simple Radioactive marker System to Reduce Positioning Errors in Radiation Treatment

Description: The objective of this research is to implement an inexpensive, quick and simple monitor that provides an accurate indication of proper patient position during the treatment of cancer by external beam X-ray radiation and also checks for any significant changes in patient anatomy. It is believed that this system will significantly reduce the treatment margin, provide an additional, independent quality assurance check of positioning accuracy prior to all treatments and reduce the probability of mi… more
Date: March 19, 2007
Creator: Miller, William H. & Palta, Dr. Jatinder
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Applications of Cfd Method to Gas Mixing Analysis in a Large-Scaled Tank

Description: The computational fluid dynamics (CFD) modeling technique was applied to the estimation of maximum benzene concentration for the vapor space inside a large-scaled and high-level radioactive waste tank at Savannah River site (SRS). The objective of the work was to perform the calculations for the benzene mixing behavior in the vapor space of Tank 48 and its impact on the local concentration of benzene. The calculations were used to evaluate the degree to which purge air mixes with benzene evolvi… more
Date: March 19, 2007
Creator: Lee, S. & Richard Dimenna, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Molecular Basis for Metabolic and Energetic Diversity

Description: We have used experimental and computational analysis of R. sphaeroides photosynthesis and other gene expression networks (Kaplan, Gomelsky, Donohue) (3-9, 12, 13, 15-18, 20). We have identified many new candidate photosynthesis genes with expression patterns that varied as a function of light intensity. Results from these experiments suggest there are many more light-regulated aspects of the photosynthetic lifestyle of this bacterium than previously appreciated. Ongoing genetic analysis confirm… more
Date: March 19, 2007
Creator: Timothy Donohue, PI
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CHEMICAL STORAGE: MYTHS VERSUS REALITY

Description: A large number of resources explaining proper chemical storage are available. These resources include books, databases/tables, and articles that explain various aspects of chemical storage including compatible chemical storage, signage, and regulatory requirements. Another source is the chemical manufacturer or distributor who provides storage information in the form of icons or color coding schemes on container labels. Despite the availability of these resources, chemical accidents stemming fr… more
Date: March 19, 2007
Creator: Simmons, F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Friction Factor Measurements in an Equally Spaced Triangular Tube Array

Description: Friction factor data for adiabatic cross-flow of water in a staggered tube array was obtained over a Reynolds number range (based on hydraulic diameter and gap velocity) of about 10,000 to 250,000. The tubes were 12.7mm (0.5 inch) outer diameter, in a uniformly spaced triangular arrangement with a pitch-to-diameter ratio of 1.5. The friction factor was compared to several literature correlations, and was found to be best matched by the Idelchik correlation. Other correlations were found to vary… more
Date: March 19, 2007
Creator: Vassallo P, Symolon P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Studies of Hydrogen Getter Material Self-decomposition and Reaction Capacity

Description: Diacetylene based hydrogen getters are examined in order to gauge their self decomposition products, as well as to determine possible origins for observed losses in origins getter capacity. Simple long term (several months) thermal aging tests were conducted, with periodic solid solid-phase micro micro-extraction (SPME) sampling followed by GC/MS analysis. The results suggest that bis(diphenylethynyl) benzene tends to decompose to give phenyl contaminants more readily than diphenylbutadiyne. Tr… more
Date: March 19, 2007
Creator: Saab, A P & Dinh, L N
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tandem Filter Development for Thermophotovoltaic Energy Conversion from January 2003 to February 2006

Description: The intent of this report is to summarize the tandem filter development for spectral control of thermophotovoltaic energy conversion from January 2003 to the termination of the program in February 2006 and to closeout tandem filter development in order to capture the knowledge gained from the development effort. Over the last three years, the goals of the tandem filter development have been the following: (1) Study the limits of the design of the interference optical coatings component of a tan… more
Date: March 19, 2007
Creator: PM, Fourspring
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Federal Employees’ Retirement System: The Role of the Thrift Savings Plan

Description: This report discusses the two retirement systems available to federal employees. The Civil Service Retirement System (CSRS) was established in 1920 and covers only employees hired before 1984. The Federal Employees' Retirement System (FERS) was created to involve Social Security, a basic retirement annuity, and the Thrift Savings Plan (TSP). The TSP is discussed and illustrated.
Date: March 19, 2007
Creator: Purcell, Patrick
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Subprime Mortgages: Primer on Current Lending and Foreclosure Issues

Description: This report discusses the issue of subprime mortgages, which are loans extended to borrowers with weak credit profiles. Subprime mortgages entail higher risk of delinquency and default. Recent increases in subprime borrower foreclosures and lender bankruptcies have prompted concerns that some lenders’ underwriting guidelines are too loose and that some borrowers may not have fully understood the risks of the mortgage products they chose. Regulatory agencies are revisiting the guidance they prov… more
Date: March 19, 2007
Creator: Murphy, Edward Vincent
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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