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FIFTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

Description: A series of experiments to monitor the aging performance of Viton{sup reg.} GLT O-rings used in the Model 9975 package has been ongoing for six years at the Savannah River National Laboratory. Sixty-seven mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested at nominal six month intervals to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-9… more
Date: November 1, 2010
Creator: Daugherty, W. & Hoffman, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quantitative Analysis of the Principal-Agent Problem in Commercial Buildings in the U.S.: Focus on Central Space Heating and Cooling

Description: We investigate the existence of the principal-agent (PA) problem in non-government, non-mall commercial buildings in the U.S. in 2003. The analysis concentrates on space heating and cooling energy consumed by centrally installed equipment in order to verify whether a market failure caused by the PA problem might have prevented the installation of energy-efficient devices in non-owner-occupied buildings (efficiency problem) and/or the efficient operation of space-conditioning equipment in these … more
Date: May 14, 2010
Creator: Blum, Helcio & Sathaye, Jayant
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of containment failure and cleanup time for Pu shots on the Z machine.

Description: Between November 30 and December 11, 2009 an evaluation was performed of the probability of containment failure and the time for cleanup of contamination of the Z machine given failure, for plutonium (Pu) experiments on the Z machine at Sandia National Laboratories (SNL). Due to the unique nature of the problem, there is little quantitative information available for the likelihood of failure of containment components or for the time to cleanup. Information for the evaluation was obtained from S… more
Date: February 1, 2010
Creator: Darby, John L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Power electronics reliability analysis.

Description: This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Ana… more
Date: December 1, 2009
Creator: Smith, Mark A. & Atcitty, Stanley
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SYNTHETIC SLING FAILURE - EVALUATIONS & RECOMMENDATIONS

Description: The information and evaluations provided in this report were compiled to address the recurring problem of synthetic sling failure. As safety is the number one priority in all work aspects, a solution must be devised to prevent accidents from occurring. A total of thirteen cases regarding synthetic sling failure were evaluated in order to determine their causes, effects, and preventative measures. From the collected data, it was found that all cases in which the synthetic sling contacted the edg… more
Date: October 26, 2009
Creator: TC, MACKEY & CS, HENDERSON
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Understanding Aprun Use Patterns

Description: On the Cray XT, aprun is the command to launch an application to a set of compute nodes reserved through the Application Level Placement Scheduler (ALPS). At the National Energy Research Scientific Computing Center (NERSC), interactive aprun is disabled. That is, invocations of aprun have to go through the batch system. Batch scripts can and often do contain several apruns which either use subsets of the reserved nodes in parallel, or use all reserved nodes in consecutive apruns. In order to be… more
Date: May 6, 2009
Creator: Lin, Hwa-Chun Wendy
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Probabilistic Mechanical Reliability Prediction of Thermoelectric Legs

Description: The probability of failure, Pf, for various square-arrayed thermoelectric device designs using bismuth telluride, lead telluride, or skutterudite thermoelectric materials were estimated. Only volume- or bulk-based Pf analysis was considered in this study. The effects of the choice of the thermoelectric material, the size of the leg array, the height of the thermoelectric legs, and the boundary conditions on the Pf of thermoelectric devices were investigated. Yielding of the solder contacts and … more
Date: May 1, 2009
Creator: Jadaan, Osama M. & Wereszczak, Andrew A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Federal Deposit Insurance Corporation (FDIC): Summary of Actions in Support of Housing and Financial Markets

Description: This report discusses recent actions taken by the Federal Deposit Insurance Corporation (FDIC) in support of housing and financial markets, including: a temporary increase in deposit insurance as required by the Emergency Economic Stabilization Act of 2008 (P.L. 110-343), the resolution of bank failures, the development of the Temporary Liquidity Guarantee Program (TLGP), and efforts to reduce foreclosures.
Date: March 5, 2009
Creator: Gonzales, Oscar R. & Getter, Darryl E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production

Description: In this simulation study, we analyzed the geomechanical response during depressurization production from two known hydrate-bearing permafrost deposits: the Mallik (Northwest Territories, Canada) deposit and Mount Elbert (Alaska, USA) deposit. Gas was produced from these deposits at constant pressure using horizontal wells placed at the top of a hydrate layer (HL), located at a depth of about 900 m at the Mallik and 600 m at the Mount Elbert. The simulation results show that general thermodynami… more
Date: February 1, 2009
Creator: Rutqvist, J.; Moridis, G.J.; Grover, T. & Collett, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and validation of a two-dimensional fast-response flood estimation model

Description: A finite difference formulation of the shallow water equations using an upwind differencing method was developed maintaining computational efficiency and accuracy such that it can be used as a fast-response flood estimation tool. The model was validated using both laboratory controlled experiments and an actual dam breach. Through the laboratory experiments, the model was shown to give good estimations of depth and velocity when compared to the measured data, as well as when compared to a more … more
Date: January 1, 2009
Creator: Judi, David R; Mcpherson, Timothy N & Burian, Steven J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Shock induced multi-mode damage in depleted uranium

Description: Recent dynamic damage studies on depleted uranium samples have revealed mixed mode failure mechanisms leading to incipient cracking as well as ductile failure processes. Results show that delamination of inclusions upon compression may provide nucleation sites for damage initiation in the form of crack tip production. However, under tension the material propagates cracks in a mixed shear localization and mode-I ductile tearing and cracking. Cracks tips appear to link up through regions of sever… more
Date: January 1, 2009
Creator: Koller, Darcie D; Cerreta, Ellen K & Gray, Ill, George T
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A surety engineering framework to reduce cognitive systems risks.

Description: Cognitive science research investigates the advancement of human cognition and neuroscience capabilities. Addressing risks associated with these advancements can counter potential program failures, legal and ethical issues, constraints to scientific research, and product vulnerabilities. Survey results, focus group discussions, cognitive science experts, and surety researchers concur technical risks exist that could impact cognitive science research in areas such as medicine, privacy, human enh… more
Date: December 1, 2008
Creator: Caudell, Thomas P. (University of New Mexico, Albuquerque, NM); Peercy, David Eugene; Caldera, Eva O. (University of New Mexico, Albuquerque, NM) & Shaneyfelt, Wendy L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Safety analysis of high pressure 3He-filled micro-channels for thermal neutron detection.

Description: This document is a safety analysis of a novel neutron detection technology developed by Sandia National Laboratories. This technology is comprised of devices with tiny channels containing high pressure {sup 3}He. These devices are further integrated into large scale neutron sensors. Modeling and preliminary device testing indicates that the time required to detect the presence of special nuclear materials may be reduced under optimal conditions by several orders of magnitude using this approach… more
Date: November 1, 2008
Creator: Ferko, Scott M.; Galambos, Paul C.; Derzon, Mark Steven & Renzi, Ronald F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Prognostic Analysis of the Tactical Quiet Generator

Description: The U.S. Army needs prognostic analysis of mission-critical equipment to enable condition-based maintenance before failure. ORNL has developed and patented prognostic technology that quantifies condition change from noisy, multi-channel, time-serial data. This report describes an initial application of ORNL's prognostic technology to the Army's Tactical Quiet Generator (TQG), which is designed to operate continuously at 10 kW. Less-than-full power operation causes unburned fuel to accumulate on… more
Date: September 1, 2008
Creator: Hively, Lee M
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

TYPE B RADIOACTIVE MATERIAL PACKAGE FAILURE MODES AND CONTENTS COMPLIANCE

Description: Type B radioactive material package failures can occur due to any one of the following: inadequate design, manufacture, and maintenance of packages, load conditions beyond those anticipated in the regulations, and improper package loading and operation. The rigorous package design evaluations performed in the certification process, robust package manufacture quality assurance programs, and demanding load conditions prescribed in the regulations are all well established. This paper focuses on th… more
Date: February 21, 2007
Creator: Watkins, R; Steve Hensel, S & Allen Smith, A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Selection of 3013 Containers for Field Surveillance

Description: This report revises and combines three earlier reports dealing with the binning, statistical sampling, and sample selection of 3013 containers for field surveillance. It includes changes to the binning specification resulting from completion of the Savannah River Site packaging campaign and new information from the shelf-life program and field surveillance activities. The revised bin assignments result in changes to the random sample specification. These changes are necessary to meet the statis… more
Date: January 1, 2007
Creator: Larry Peppers, Elizabeth Kelly, James McClard, Gary Friday, Theodore Venetz, and Jerry Stakebade
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Updating time-to-failure distributions based on field observations and sensor data.

Description: Enterprise level logistics and prognostics and health management (PHM) modeling efforts use reliability focused failure distributions to characterize the probability of failure over the lifetime of a component. This research characterized the Sandia National Laboratories developed combined lifecycle (CMBL) distribution and explored methods for updating this distribution as systems age and new failure data becomes available. The initial results obtained in applying a Bayesian sequential updating… more
Date: October 1, 2006
Creator: Lowder, Kelly S.; Briand, Daniel & Shirah, Donald
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Review of Software-Induced Failure Experience.

Description: We present a review of software-induced failures in commercial nuclear power plants (NPPs) and in several non-nuclear industries. We discuss the approach used for connecting operational events related to these failures and the insights gained from this review. In particular, we elaborate on insights that can be used to model this kind of failure in a probabilistic risk assessment (PRA) model. We present the conclusions reached in these areas.
Date: September 1, 2006
Creator: Chu, T. L.; Martinez-Guridi, G.; Yue, M. & Lehner, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Stress-Assisted Corrosion in Boiler Tubes

Description: A number of industrial boilers, including in the pulp and paper industry, needed to replace their lower furnace tubes or decommission many recovery boilers due to stress-assisted corrosion (SAC) on the waterside of boiler tubes. More than half of the power and recovery boilers that have been inspected reveal SAC damage, which portends significant energy and economic impacts. The goal of this project was to clarify the mechanism of stress-assisted corrosion (SAC) of boiler tubes for the purpose … more
Date: May 27, 2006
Creator: Singh, Preet M. & Pawel, Steven J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Estimation of Failure Rates of Digital Components Using a Hierarchical Bayesian Method.

Description: One of the greatest challenges in evaluating reliability of digital I&C systems is how to obtain better failure rate estimates of digital components. A common practice of the digital component failure rate estimation is attempting to use empirical formulae to capture the impacts of various factors on the failure rates. The applicability of an empirical formula is questionable because it is not based on laws of physics and requires good data, which is scarce in general. In this study, the co… more
Date: January 30, 2006
Creator: Yue, M. & Chu, T. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Comparison and Evaluation of Three Fiber Composite Failure Criteria

Description: Three specific failure criteria for the transversely isotropic fiber composite case will be discussed. All three use the polynomial expansion method. The three criteria are the Tsai-Wu criterion, the Hashin criterion and the Christensen criterion. All three criteria will be given in forms that admit direct and easy comparison, which has not usually been done. The central differences between these three criteria will be discussed, and steps will be taken toward the evaluation of them.
Date: February 8, 2005
Creator: Christensen, R M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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