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Multi-Resolution Markov-Chain-Monte-Carlo Approach for System Identification with an Application to Finite-Element Models

Description: Estimating unknown system configurations/parameters by combining system knowledge gained from a computer simulation model on one hand and from observed data on the other hand is challenging. An example of such inverse problem is detecting and localizing potential flaws or changes in a structure by using a finite-element model and measured vibration/displacement data. We propose a probabilistic approach based on Bayesian methodology. This approach does not only yield a single best-guess solution… more
Date: February 7, 2005
Creator: Johannesson, G.; Glaser, R. E.; Lee, C. L.; Nitao, J. J. & Hanley, W. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phenomenology treatment of magnetohydrodynamic turbulence with non-equipartition and anisotropy

Description: Magnetohydrodynamics (MHD) turbulence theory, often employed satisfactorily in astrophysical applications, has often focused on parameter ranges that imply nearly equal values of kinetic and magnetic energies and length scales. However, MHD flow may have disparity magnetic Prandtl number, dissimilar kinetic and magnetic Reynolds number, different kinetic and magnetic outer length scales, and strong anisotropy. Here a phenomenology for such ''non-equipartitioned'' MHD flow is discussed. Two cond… more
Date: February 7, 2005
Creator: Zhou, Y & Matthaeus, W H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Defining Electron Backscatter Diffraction Resolution

Description: Automated electron backscatter diffraction (EBSD) mapping systems have existed for more than 10 years [1,2], and due to their versatility in characterizing multiple aspects of microstructure, they have become an important tool in microscale crystallographic studies. Their increasingly widespread use however raises questions about their accuracy in both determining crystallographic orientations, as well as ensuring that the orientation information is spatially correct. The issue of orientation a… more
Date: February 7, 2005
Creator: El-Dasher, B S & Rollett, A D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

String-Corrected Black Holes

Description: We investigate the geometry of four dimensional black hole solutions in the presence of stringy higher curvature corrections to the low energy effective action. For certain supersymmetric two charge black holes these corrections drastically alter the causal structure of the solution, converting seemingly pathological null singularities into timelike singularities hidden behind a finite area horizon. We establish, analytically and numerically, that the string-corrected two-charge black hole metr… more
Date: February 7, 2005
Creator: Hubeny, Veronika; Maloney, Alexander & Rangamani, Mukund
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Institute for Scientific Computing Research Annual Report: Fiscal Year 2004

Description: Large-scale scientific computation and all of the disciplines that support and help to validate it have been placed at the focus of Lawrence Livermore National Laboratory (LLNL) by the Advanced Simulation and Computing (ASC) program of the National Nuclear Security Administration (NNSA) and the Scientific Discovery through Advanced Computing (SciDAC) initiative of the Office of Science of the Department of Energy (DOE). The maturation of computational simulation as a tool of scientific and engi… more
Date: February 7, 2005
Creator: Keyes, D. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Error bounds from extra precise iterative refinement

Description: We present the design and testing of an algorithm for iterative refinement of the solution of linear equations, where the residual is computed with extra precision. This algorithm was originally proposed in the 1960s [6, 22] as a means to compute very accurate solutions to all but the most ill-conditioned linear systems of equations. However two obstacles have until now prevented its adoption in standard subroutine libraries like LAPACK: (1) There was no standard way to access the higher precis… more
Date: February 7, 2005
Creator: Demmel, James; Hida, Yozo; Kahan, William; Li, Xiaoye S.; Mukherjee, Soni & Riedy, E. Jason
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Beryllium Sampling and Analysis Within the DOE Complex and Opportunities for Standardization

Description: Since the U. S. Department of Energy published the DOE Beryllium Rule, 10 CFR 850, in 1999, DOE sites have been required to measure beryllium on air filters and wipes for worker protection and for release of materials from beryllium-controlled areas. Measurements in the nanogram range on a filter or wipe are typically required. Industrial hygiene laboratories have applied methods from various analytical compendia, and a number of issues have emerged with sampling and analysis practices. As a re… more
Date: February 7, 2005
Creator: MICHAEL, BRISSON
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Lignite Fuel Enhancement Progress Report

Description: The Design Team continued to conference this quarter. Their primary task during this timeframe was to finalize the dryer design based on information learned from the NDIC Pilot work and detailed design discussions at Barr offices in August. Heyl-Patterson was tasked with incorporating all comments and drafting drawings. They submitted a preliminary proposal which spawned detailed discussions about tube bundle, air locks, and fire suppression systems. The type of fire protection specified dictat… more
Date: February 7, 2005
Creator: Bullinger, Charles
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

AGING SYSTEM DESIGN DEVELOPMENT STRATEGY

Description: This plan provides an overview, work to date, and the path forward for the design development strategy of the Aging cask for aging commercial spent nuclear fuel (CSNF) at the Yucca Mountain Project (YMP) repository site. Waste for subsurface emplacement at the repository includes US Department of Energy (DOE) high-level radioactive waste (HLW), DOE SNF, commercial fuel in dual-purpose canisters (DPCs), uncanistered bare fuel, naval fuel, and other waste types. Table 1-1 lists the types of radio… more
Date: February 7, 2005
Creator: Beesley, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

DEVELOPMENT OF BYPASSED OIL RESERVES USING BEHIND CASING RESISTIVITY MEASUREMENTS

Description: Tubing and rods of the S.P. Pedro-Nepple No.1 well were pulled and the well was prepared for running of Schlumberger's Cased Hole Formation Resistivity Tool (CHFR) in selected intervals. The CHFR tool was successfully run and data was captured. The CHFR formation resistivity readings were compared to original open hole resistivity measurements. Separation between the original and CHFR resistivity curves indicate both swept and un-swept sand intervals. Both watered out sand intervals and those w… more
Date: February 7, 2005
Creator: Conner, Michael G. & Blesener, Jeffrey A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EVALUATION OF WETTING AGENTS TO MITIGATE DUSTING WHEN TRANSFERRING DRY GLASS FORMER CHEMICALS

Description: Plant design support for the US Department of Energy (DOE) River Protection Project (RPP) - Waste Treatment Plant (WTP) required pilot scale testing of the High Level Waste (HLW) glass former chemical (GFC) delivery system. A pilot facility was assembled at the Clemson Environmental Technology Laboratory (CETL) under the direction of the Savannah River National Laboratory (SRNL). Tests were performed using a representative HLW GFC blend to determine the behavior of the dry chemicals when transp… more
Date: February 7, 2005
Creator: TIMOTHY, JONES
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Numerical simulation of a laboratory-scale turbulent V-flame

Description: We present a three-dimensional, time-dependent simulation of a laboratory-scale rod-stabilized premixed turbulent V-flame. The simulations are performed using an adaptive time-dependent low Mach number model with detailed chemical kinetics and a mixture model for differential species diffusion. The algorithm is based on a second-order projection formulation and does not require an explicit subgrid model for turbulence or turbulence chemistry interaction. Adaptive mesh refinement is used to dyna… more
Date: February 7, 2005
Creator: Bell, J. B.; Day, M. S.; Shepherd, I. G.; Johnson, M.; Cheng, R. K.; Grcar, J. F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Scoping Studies to Develop a Method to Determine Particle Size in Simulant Sludge Slurries by Sieving

Description: A physical separation method (i.e. sieving) was investigated to determine particle size distribution in non-radioactive sludge slurry simulants with the goal of implementation into the SRNL (Savannah River National Laboratory) shielded cells for use with radioactive sludge slurries. The investigation included obtaining the necessary experimental equipment, developing accessory equipment for use with the sieve shaker (to be able to sieve simulant slurries with aqueous solutions), sieving three d… more
Date: February 7, 2005
Creator: Click, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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