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Nuclear Safety: Department of Energy Needs to Strengthen Its Independent Oversight of Nuclear Facilities and Operations (open access)

Nuclear Safety: Department of Energy Needs to Strengthen Its Independent Oversight of Nuclear Facilities and Operations

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Energy (DOE) oversees contractors that operate more than 200 "high-hazard" nuclear facilities, where an accident could have serious consequences for workers and the public. DOE is charged with regulating the safety of these facilities. A key part of DOE's self-regulation is the Office of Health, Safety and Security (HSS), which develops, oversees, and helps enforce nuclear safety policies. This is the only DOE safety office intended to be independent of the program offices, which carry out mission responsibilities. This report examines (1) the extent to which HSS meets GAO's elements of effective independent nuclear safety oversight and (2) the factors contributing to any identified shortcomings with respect to these elements. GAO reviewed relevant DOE policies, interviewed officials and outside safety experts, and surveyed DOE sites to determine the number and status of nuclear facilities. GAO also assessed oversight practices against the criteria for independent oversight GAO developed based on a series of reports on DOE nuclear safety and discussions with nuclear safety experts."
Date: October 23, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Multiple-code simulation study of the long-term EDZ evolution of geological nuclear waste repositories (open access)

Multiple-code simulation study of the long-term EDZ evolution of geological nuclear waste repositories

This simulation study shows how widely different model approaches can be adapted to model the evolution of the excavation disturbed zone (EDZ) around a heated nuclear waste emplacement drift in fractured rock. The study includes modeling of coupled thermal-hydrological-mechanical (THM) processes, with simplified consideration of chemical coupling in terms of time-dependent strength degradation or subcritical crack growth. The different model approaches applied in this study include boundary element, finite element, finite difference, particle mechanics, and elastoplastic cellular automata methods. The simulation results indicate that thermally induced differential stresses near the top of the emplacement drift may cause progressive failure and permeability changes during the first 100 years (i.e., after emplacement and drift closure). Moreover, the results indicate that time-dependent mechanical changes may play only a small role during the first 100 years of increasing temperature and thermal stress, whereas such time-dependency is insignificant after peak temperature, because decreasing thermal stress.
Date: October 23, 2008
Creator: Rutqvist, J.; Backstrom, A.; Chijimatsu, M.; Feng, X. T.; Pan, P. Z.; Hudson, J. et al.
Object Type: Article
System: The UNT Digital Library
Large File System Backup: NERSC Global File System Experience (open access)

Large File System Backup: NERSC Global File System Experience

NERSC's Global File system (NGF), accessible from all compute systems at NERSC, holds files and data from many scientific projects. A full backup of this file system to our High Performance Storage System (HPSS) is performed periodically. Disk storage usage by projects at NERSC has grown seven fold over a two year period, from ~;;20TB in June 2006 to ~;;140 TB in June 2008. The latest full backup took about 13 days and more than 200 T10k tape cartridges (.5 TB capacity). Petabyte file systems are becoming a reality in the next few years and the existing utilities are already strained in handling backup tasks.
Date: October 23, 2008
Creator: Mokhtarani, Akbar; Andrews, Matthew; Hick, Jason & Kramer, William
Object Type: Report
System: The UNT Digital Library
MATRIX 2 RESULTS OF THE FY07 ENHANCED DOE HIGH-LEVEL WASTE MELTER THROUGHPUT STUDIES AT SRNL (open access)

MATRIX 2 RESULTS OF THE FY07 ENHANCED DOE HIGH-LEVEL WASTE MELTER THROUGHPUT STUDIES AT SRNL

High-level waste (HLW) throughput (i.e., the amount of waste processed per unit time) is a function of two critical parameters: waste loading (WL) and melt rate. For the Waste Treatment and Immobilization Plant (WTP) at the Hanford Site and the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), increasing HLW throughput would significantly reduce the overall mission life cycle costs for the Department of Energy (DOE). The objective of this study was to generate supplemental validation data that could be used to determine the applicability of the current liquidus temperature (TL) model to expanded DWPF glass composition regions of interest based on higher WLs. Two specific flowsheets were used in this study to provide such insight: (1) Higher WL glasses (45 and 50%) based on future sludge batches that have (and have not) undergone the Al-dissolution process. (2) Coupled operations supported by the Salt Waste Processing Facility (SWPF), which increase the TiO{sub 2} concentration in glass to greater than 2 wt%. Glasses were also selected to address technical issues associated with Al{sub 2}O{sub 3} solubility, nepheline formation, and homogeneity issues for coupled operations. A test matrix of 28 glass compositions was developed to provide insight into these …
Date: October 23, 2008
Creator: Raszewski, F; Tommy Edwards, T & David Peeler, D
Object Type: Report
System: The UNT Digital Library
A comparative simulation study of coupled THM processes and their effect on fractured rock permeability around nuclear waste repositories (open access)

A comparative simulation study of coupled THM processes and their effect on fractured rock permeability around nuclear waste repositories

This paper presents an international, multiple-code, simulation study of coupled thermal, hydrological, and mechanical (THM) processes and their effect on permeability and fluid flow in fractured rock around heated underground nuclear waste emplacement drifts. Simulations were conducted considering two types of repository settings: (a) open emplacement drifts in relatively shallow unsaturated volcanic rock, and (b) backfilled emplacement drifts in deeper saturated crystalline rock. The results showed that for the two assumed repository settings, the dominant mechanism of changes in rock permeability was thermal-mechanically-induced closure (reduced aperture) of vertical fractures, caused by thermal stress resulting from repository-wide heating of the rock mass. The magnitude of thermal-mechanically-induced changes in permeability was more substantial in the case of an emplacement drift located in a relatively shallow, low-stress environment where the rock is more compliant, allowing more substantial fracture closure during thermal stressing. However, in both of the assumed repository settings in this study, the thermal-mechanically-induced changes in permeability caused relatively small changes in the flow field, with most changes occurring in the vicinity of the emplacement drifts.
Date: October 23, 2008
Creator: Rutqvist, Jonny; Barr, Deborah; Birkholzer, Jens T.; Fujisaki, Kiyoshi; Kolditz, Olf; Liu, Quan-Shen et al.
Object Type: Article
System: The UNT Digital Library
National Energy Research Scientific Computing Center 2007 Annual Report (open access)

National Energy Research Scientific Computing Center 2007 Annual Report

This report presents highlights of the research conducted on NERSC computers in a variety of scientific disciplines during the year 2007. It also reports on changes and upgrades to NERSC's systems and services aswell as activities of NERSC staff.
Date: October 23, 2008
Creator: Hules, John A.; Bashor, Jon; Wang, Ucilia; Yarris, Lynn & Preuss, Paul
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 451, Ed. 1 Thursday, October 23, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 451, Ed. 1 Thursday, October 23, 2008

Free weekly newspaper that includes business and classified advertising.
Date: October 23, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 39, No. 453, Ed. 1 Thursday, October 23, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 453, Ed. 1 Thursday, October 23, 2008

Free weekly newspaper that includes business and classified advertising.
Date: October 23, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 38, No. 43, Ed. 1 Thursday, October 23, 2008 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 38, No. 43, Ed. 1 Thursday, October 23, 2008

Weekly newspaper from Port Aransas, Texas that includes local, state and national news along with extensive advertising.
Date: October 23, 2008
Creator: Judson, Mary Henkel
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 92, No. 35, Ed. 1 Thursday, October 23, 2008 (open access)

North Texas Daily (Denton, Tex.), Vol. 92, No. 35, Ed. 1 Thursday, October 23, 2008

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: October 23, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Texas Jewish Post (Fort Worth, Tex.), Vol. 63, No. 43, Ed. 1 Thursday, October 23, 2008 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 63, No. 43, Ed. 1 Thursday, October 23, 2008

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state and national news along with extensive advertising.
Date: October 23, 2008
Creator: Wisch, Rene
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 118, No. 43, Ed. 1 Thursday, October 23, 2008 (open access)

The Canadian Record (Canadian, Tex.), Vol. 118, No. 43, Ed. 1 Thursday, October 23, 2008

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: October 23, 2008
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 69, Ed. 1 Thursday, October 23, 2008 (open access)

The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 69, Ed. 1 Thursday, October 23, 2008

Semi-weekly newspaper from Bastrop, Texas that includes local, state and national news along with advertising.
Date: October 23, 2008
Creator: Wright, Cyndi
Object Type: Newspaper
System: The Portal to Texas History
Federal Research and Development Funding: FY2009 (open access)

Federal Research and Development Funding: FY2009

None
Date: October 23, 2008
Creator: Sargent, John F.; Matthews, Christine M.; Moteff, John D.; Morgan, Daniel; Esworthy, Robert; Schacht, Wendy H. et al.
Object Type: Report
System: The UNT Digital Library
The Executive Schedule IV Pay Cap on General Schedule Compensation (open access)

The Executive Schedule IV Pay Cap on General Schedule Compensation

None
Date: October 23, 2008
Creator: Copeland, Curtis W.
Object Type: Report
System: The UNT Digital Library
Nepal: Political Developments and Bilateral Relations with the United States (open access)

Nepal: Political Developments and Bilateral Relations with the United States

This report concerns the political developments and bilateral relations of Nepal with the United States. Nepal has been described as a yam between two boulders. Nepal's geopolitical status as a small, landlocked buffer state situated between two Asian giants - India and China - has severely constrained its foreign policy and trade options. Although Nepal has sought to maintain friendly relations with both neighbors, its cultural, linguistic, religious and economic ties with India historically have been much closer than those with China.
Date: October 23, 2008
Creator: Vaughn, Bruce
Object Type: Report
System: The UNT Digital Library
Greensheet (Fort Worth, Tex.), Vol. 32, No. 200, Ed. 1 Thursday, October 23, 2008 (open access)

Greensheet (Fort Worth, Tex.), Vol. 32, No. 200, Ed. 1 Thursday, October 23, 2008

Free weekly newspaper that includes business and classified advertising.
Date: October 23, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Fort Worth, Tex.), Vol. 32, No. 201, Ed. 1 Thursday, October 23, 2008 (open access)

Greensheet (Fort Worth, Tex.), Vol. 32, No. 201, Ed. 1 Thursday, October 23, 2008

Free weekly newspaper that includes business and classified advertising.
Date: October 23, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 32, No. 199, Ed. 1 Thursday, October 23, 2008 (open access)

The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 32, No. 199, Ed. 1 Thursday, October 23, 2008

Free weekly newspaper that includes business and classified advertising.
Date: October 23, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Archer County News (Archer City, Tex.), No. 43, Ed. 1 Thursday, October 23, 2008 (open access)

Archer County News (Archer City, Tex.), No. 43, Ed. 1 Thursday, October 23, 2008

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: October 23, 2008
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
Lexington Observer (Lexington, Okla.), Vol. 13, No. 29, Ed. 1 Thursday, October 23, 2008 (open access)

Lexington Observer (Lexington, Okla.), Vol. 13, No. 29, Ed. 1 Thursday, October 23, 2008

Weekly newspaper from Lexington, Oklahoma that includes local, state, and national news along with advertising.
Date: October 23, 2008
Creator: Edwards, Olvis
Object Type: Newspaper
System: The Gateway to Oklahoma History
Comanche Chief (Comanche, Tex.), No. 26, Ed. 1 Thursday, October 23, 2008 (open access)

Comanche Chief (Comanche, Tex.), No. 26, Ed. 1 Thursday, October 23, 2008

Weekly newspaper from Comanche, Texas that includes local, state, and national news along with advertising.
Date: October 23, 2008
Creator: Wilkerson, James C., III
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 43, Ed. 1 Thursday, October 23, 2008 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 26, No. 43, Ed. 1 Thursday, October 23, 2008

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: October 23, 2008
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Extracellular matrix control of mammary gland morphogenesis and tumorigenesis: insights from imaging (open access)

Extracellular matrix control of mammary gland morphogenesis and tumorigenesis: insights from imaging

The extracellular matrix (ECM), once thought to solely provide physical support to a tissue, is a key component of a cell's microenvironment responsible for directing cell fate and maintaining tissue specificity. It stands to reason, then, that changes in the ECM itself or in how signals from the ECM are presented to or interpreted by cells can disrupt tissue organization; the latter is a necessary step for malignant progression. In this review, we elaborate on this concept using the mammary gland as an example. We describe how the ECM directs mammary gland formation and function, and discuss how a cell's inability to interpret these signals - whether as a result of genetic insults or physicochemical alterations in the ECM - disorganizes the gland and promotes malignancy. By restoring context and forcing cells to properly interpret these native signals, aberrant behavior can be quelled and organization re-established. Traditional imaging approaches have been a key complement to the standard biochemical, molecular, and cell biology approaches used in these studies. Utilizing imaging modalities with enhanced spatial resolution in live tissues may uncover additional means by which the ECM regulates tissue structure, on different length scales, through its pericellular organization (short-scale) and by biasing …
Date: October 23, 2008
Creator: Ghajar, Cyrus M & Bissell, Mina J
Object Type: Article
System: The UNT Digital Library