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Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes (open access)

Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes

The US Department of Energy (DOE), in order to increase the diversity of rock types under consideration by the geologic disposal program, initiated the Sedimary ROck Program (SERP), whose immediate objectiv eis to evaluate five types of secimdnary rock - sandstone, chalk, carbonate rocks (limestone and dolostone), anhydrock, and shale - to determine the potential for siting a geologic repository. The evaluation of these five rock types, together with the ongoing salt studies, effectively results in the consideration of all types of relatively impermeable sedimentary rock for repository purposes. The results of this evaluation are expressed in terms of a ranking of the five rock types with respect to their potential to serve as a geologic repository host rock. This comparative evaluation was conducted on a non-site-specific basis, by use of generic information together with rock evaluation criteria (RECs) derived from the DOE siting guidelines for geologic repositories (CFR 1984). An information base relevant to rock evaluation using these RECs was developed in hydrology, geochemistry, rock characteristics (rock occurrences, thermal response, rock mechanics), natural resources, and rock dissolution. Evaluation against postclosure and preclosure RECs yielded a ranking of the five subject rocks with respect to their potential as repository host …
Date: November 15, 2003
Creator: Croff, A. G.; Lomenick, T. F.; Lowrie, R. S. & Stow, S. H.
Object Type: Report
System: The UNT Digital Library
[Clipping: A clear-eyed look at the Kennedy years] (open access)

[Clipping: A clear-eyed look at the Kennedy years]

Newspaper clipping discussing the 40th anniversary of the assassination of former President John F. Kennedy. The clipping only includes the front page of the article and the back-page, and there are red markings in pen.
Date: November 15, 2003
Creator: Chism, Olin
Object Type: Clipping
System: The UNT Digital Library
CROSSCUTTING TECHNOLOGY DEVELOPMENT AT THE CENTER FOR ADVANCED SEPARATION TECHNOLOGIES (open access)

CROSSCUTTING TECHNOLOGY DEVELOPMENT AT THE CENTER FOR ADVANCED SEPARATION TECHNOLOGIES

The U.S. is the largest producer of mining products in the world. In 1999, U.S. mining operations produced $66.7 billion worth of raw materials that contributed a total of $533 billion to the nation's wealth. Despite these contributions, the mining industry has not been well supported with research and development funds as compared to mining industries in other countries. To overcome this problem, the Center for Advanced Separation Technologies (CAST) was established to develop technologies that can be used by the U.S. mining industry to create new products, reduce production costs, and meet environmental regulations. Much of the research to be conducted with Cooperative Agreement funds will be longer-term, high-risk, basic research and will be carried out in five broad areas: (a) Solid-solid separation (b) Solid-liquid separation (c) Chemical/Biological Extraction (d) Modeling and Control, and (e) Environmental Control. Distribution of funds is being handled via competitive solicitation of research proposals through Site Coordinators at the seven member universities. The first of these solicitations, referred to as the CAST II-Round 1 RFP, was issued on October 28, 2002. Thirty-eight proposals were received by the December 10, 2002 deadline for this RFP-eleven (11) Solid-Solid Separation, seven (7) Solid-Liquid Separation, ten (10) Chemical/Biological …
Date: November 15, 2003
Creator: Rimmer, Hugh W.
Object Type: Report
System: The UNT Digital Library
ACCIDENT ANALYSES & CONTROL OPTIONS IN SUPPORT OF THE SLUDGE WATER SYSTEM SAFETY ANALYSIS (open access)

ACCIDENT ANALYSES & CONTROL OPTIONS IN SUPPORT OF THE SLUDGE WATER SYSTEM SAFETY ANALYSIS

This report documents the accident analyses and nuclear safety control options for use in Revision 7 of HNF-SD-WM-SAR-062, ''K Basins Safety Analysis Report'' and Revision 4 of HNF-SD-SNF-TSR-001, ''Technical Safety Requirements - 100 KE and 100 KW Fuel Storage Basins''. These documents will define the authorization basis for Sludge Water System (SWS) operations. This report follows the guidance of DOE-STD-3009-94, ''Preparation Guide for US. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports'', for calculating onsite and offsite consequences. The accident analysis summary is shown in Table ES-1 below. While this document describes and discusses potential control options to either mitigate or prevent the accidents discussed herein, it should be made clear that the final control selection for any accident is determined and presented in HNF-SD-WM-SAR-062.
Date: November 15, 2003
Creator: Williams, J. C.
Object Type: Report
System: The UNT Digital Library
Noise propagation in iterative reconstruction algorithms with line searches (open access)

Noise propagation in iterative reconstruction algorithms with line searches

In this paper we analyze the propagation of noise in iterative image reconstruction algorithms. We derive theoretical expressions for the general form of preconditioned gradient algorithms with line searches. The results are applicable to a wide range of iterative reconstruction problems, such as emission tomography, transmission tomography, and image restoration. A unique contribution of this paper comparing to our previous work [1] is that the line search is explicitly modeled and we do not use the approximation that the gradient of the objective function is zero. As a result, the error in the estimate of noise at early iterations is significantly reduced.
Date: November 15, 2003
Creator: Qi, Jinyi
Object Type: Article
System: The UNT Digital Library
Septa design for a prostate specific PET camera (open access)

Septa design for a prostate specific PET camera

The recent development of new prostate tracers has motivated us to build a low cost PET camera optimized to image the prostate. Coincidence imaging of positron emitters is achieved using a pair of external curved detector banks. The bottom bank is fixed below the patient bed, and the top bank moves upward for patient access and downward for maximum sensitivity. In this paper, we study the design of septa for the prostate camera using Monte Carlo simulations. The system performance is measured by the detectability of a prostate lesion. We have studied 17 septa configurations. The results show that the design of septa has a large impact on the lesion detection at a given activity concentration. Significant differences are also observed between the lesion detectability and the conventional noise equivalent count (NEC) performance, indicating that the NEC is not appropriate for the detection task.
Date: November 15, 2003
Creator: Qi, Jinyi; Huber, Jennifer S.; Huesman, Ronald H.; Moses, William W.; Derenzo, Stephen E. & Budinger, Thomas F.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 350, Ed. 1 Saturday, November 15, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 350, Ed. 1 Saturday, November 15, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 15, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 21, No. 22, Ed. 1 Saturday, November 15, 2003 (open access)

The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 21, No. 22, Ed. 1 Saturday, November 15, 2003

Semi-monthly newspaper from Oklahoma City, Oklahoma that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: November 15, 2003
Creator: Hawkins, Don
Object Type: Newspaper
System: The UNT Digital Library
Statistical Modeling of Large-Scale Scientific Simulation Data (open access)

Statistical Modeling of Large-Scale Scientific Simulation Data

With the advent of massively parallel computer systems, scientists are now able to simulate complex phenomena (e.g., explosions of a stars). Such scientific simulations typically generate large-scale data sets over the spatio-temporal space. Unfortunately, the sheer sizes of the generated data sets make efficient exploration of them impossible. Constructing queriable statistical models is an essential step in helping scientists glean new insight from their computer simulations. We define queriable statistical models to be descriptive statistics that (1) summarize and describe the data within a user-defined modeling error, and (2) are able to answer complex range-based queries over the spatiotemporal dimensions. In this chapter, we describe systems that build queriable statistical models for large-scale scientific simulation data sets. In particular, we present our Ad-hoc Queries for Simulation (AQSim) infrastructure, which reduces the data storage requirements and query access times by (1) creating and storing queriable statistical models of the data at multiple resolutions, and (2) evaluating queries on these models of the data instead of the entire data set. Within AQSim, we focus on three simple but effective statistical modeling techniques. AQSim's first modeling technique (called univariate mean modeler) computes the ''true'' (unbiased) mean of systematic partitions of the data. AQSim's …
Date: November 15, 2003
Creator: Eliassi-Rad, T.; Baldwin, C.; Abdulla, G. & Critchlow, T.
Object Type: Book
System: The UNT Digital Library
Propagation of errors from the sensitivity image in list mode reconstruction (open access)

Propagation of errors from the sensitivity image in list mode reconstruction

List mode image reconstruction is attracting renewed attention. It eliminates the storage of empty sinogram bins. However, a single back projection of all LORs is still necessary for the pre-calculation of a sensitivity image. Since the detection sensitivity is dependent on the object attenuation and detector efficiency, it must be computed for each study. Exact computation of the sensitivity image can be a daunting task for modern scanners with huge numbers of LORs. Thus, some fast approximate calculation may be desirable. In this paper, we theoretically analyze the error propagation from the sensitivity image into the reconstructed image. The theoretical analysis is based on the fixed point condition of the list mode reconstruction. The non-negativity constraint is modeled using the Kuhn-Tucker condition. With certain assumptions and the first order Taylor series approximation, we derive a closed form expression for the error in the reconstructed image as a function of the error in the sensitivity image. The result provides insights on what kind of error might be allowable in the sensitivity image. Computer simulations show that the theoretical results are in good agreement with the measured results.
Date: November 15, 2003
Creator: Qi, Jinyi & Huesman, Ronald H.
Object Type: Article
System: The UNT Digital Library
[Philip Rose] captions transcript

[Philip Rose]

Video recording from The Black Academy of Arts and Letters recorded during their Philip Rose event in 2003. This video features a talk from author Philip Rose live on stage at Clarence Muse Café Theatre with discussions with the audience.
Date: November 15, 2003
Creator: unknown
Object Type: Video
System: The UNT Digital Library