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Utilization of Technology-Enhanced Delphi Techniques

Description: This article discusses the Delphi consensus-building technique. Also discussed are the Delphi Technique's history, the process, and some advantages and disadvantages found in the literature. Finally, this article examines a technology-enhanced version of the process.
Date: 2002
Creator: Andrews, Charles G. & Allen, Jeff M.
Partner: UNT College of Information

Virtual Libraries: A Service-Based Approach for Virtual Libraries

Description: Article discussing a service-based approach for virtual libraries and the provision of services to patrons and other users built upon the collective personnel, information, and technological resources that constitute the library.
Date: Autumn 2002
Creator: Moen, William E. & Murray, Kathleen R.
Partner: UNT College of Information

Structural and compositional modifications in lignin of transgenic alfalfa down-regulated in caffeic acid 3-O-methyltransferase and caffeoyl coenzyme A 3-O-methyltransferase

Description: Article on the structural and compositional modifications in lignin of transgenic alfalfa down-regulated in caffeic acid 3-O-methyltransferase and caffeoyl coenzyme A 3-O-methyltransferase.
Date: July 8, 2002
Creator: Marita, Jane M.; Ralph, John; Hatfield, Ronald D.; Guo, Dianjing; Chen, Fang & Dixon, R. A.
Partner: UNT College of Arts and Sciences

Ventilation rates and health

Description: No abstract prepared.
Date: August 1, 2002
Creator: Seppanen, Olli; Fisk, William J. & Mendell, Mark J.
Partner: UNT Libraries Government Documents Department

Tevatron Run II performance and plans

Description: The Fermilab accelerator complex has been operating Run II for approximately one year. In this mode 36 proton bunches collide with 36 antiproton bunches at 2 interaction regions in the Tevatron at 980 GeV beam energy. The long range goal in Run II is to obtain a total integrated luminosity of 15 pb{sup -1}. The current status and performance of the accelerator complex is described, including the Tevatron, Main Injector, Antiproton Source, and Recycler Ring. Future upgrade plans and prospects for reaching the admittedly ambitious long range goal are presented.
Date: July 12, 2002
Creator: Church, Michael D
Partner: UNT Libraries Government Documents Department

PRELIMINARY DESIGN OF THE BEAM LOSS MONITORING SYSTEM FOR THE SNS.

Description: The SNS to be built at Oak Ridge National Laboratory will provide a high average intensity 1 GeV beam to produce spallation neutrons. Loss of a even small percentage of this intense beam would result in high radiation. The Beam Loss Monitor (ELM) system must detect such small, long term losses yet be capable of measuring infrequent short high losses. The large dynamic range presents special problems for the system design. Ion chambers will be used as the detectors. A detector originally designed for the FNAL Tevatron, was considered but concerns about ion collection times and low collection efficiency at high loss rates favor a new design. The requirements and design concepts of the proposed approach will be presented. Discussion of the design and testing of the ion chambers and the analog j-Point end electronics will be presented. The overall system design will be described.
Date: May 6, 2002
Creator: WITKOVER,R. & GASSNER,D.
Partner: UNT Libraries Government Documents Department

Recent Progress on the Standardized DOE Spent Nuclear Fuel Canister

Description: The Department of Energy (DOE) has developed a set of containers for the handling, interim storage, transportation, and disposal in the national repository of DOE spent nuclear fuel (SNF). This container design, referred to as the standardized DOE SNF canister or standardized canister, was developed by the Department's National Spent Nuclear Fuel Storage Program (NSNFP) working in conjunction with the Office of Civilian Radioactive Waste Management (OCRWM) and the DOE spent fuel sites. This canister had to have a standardized design yet be capable of accepting virtually all of the DOE SNF, be placed in a variety of storage and transportation systems, and still be acceptable to the repository. Since specific design details regarding the storage, transportation, and repository disposal of DOE SNF were not finalized, the NSNFP recognized the necessity to specify a complete DOE SNF canister design. This allowed other evaluations of canister performance and design to proceed as well as providing standardized canister users adequate information to proceed with their work. This paper is an update of a paper presented to the 1999 American Nuclear Society of Mechanical Engineers (ASME) Pressure Vessels and Piping (PVP) Conference. It discusses recent progress achieved in various areas to enhance acceptance of this canister not only by the DOE complex but also fabricators and regulatory agencies.
Date: May 7, 2002
Creator: Morton, D.K.; Snow, S.D.; Rahl, T.E.; Hill, T.J. (INEEL) & Morissette, R.P. (Beckman and Associates, Inc.)
Partner: UNT Libraries Government Documents Department

Deep Inelastic Scattering from Light Nuclei

Description: We review recent developments in the study of deep inelastic scattering from light nuclei, focusing in particular on deuterium, helium, and lithium nuclei. Understanding the nuclear effects in these systems is essential for the extraction of information on the neutron structure function.
Date: April 1, 2002
Creator: Melnitchouk, Wally & Thomas, A.W.
Partner: UNT Libraries Government Documents Department

Summary and highlights of the 14th Topical Conference on Hadron Collider Physics (HCP2002)

Description: First of all, I would like to thank the scientific committee, the conference organizers, the University of Karlsruhe and the Institute for Experimental Nuclear Physics, all of the speakers, and the conference secretariat, for making this an extremely well-organized and uniformly high-quality meeting. I would also like to thank all of the speakers who provided me with material for my talk before and during the conference. There is obviously no point in these proceedings in attempting to repeat all of the material from the individual contributions; by definition, these are all available earlier in this volume. In the written version, therefore, I will try to give a high level overview of the current state of hadron collider physics and to highlight the connections between the many presentations at this conference.
Date: November 13, 2002
Creator: Womersley, John
Partner: UNT Libraries Government Documents Department

Synchrotron radiation issues in future hadron colliders

Description: Hadron machines mostly use high field superconducting magnets operating at low temperatures. Therefore the issue of extracting a SR power heat load becomes more critical and costly. Conceptual solutions to the problem exist in the form of beam screens and photon stops. Cooled beam screens are more expensive in production and operation than photon stops, but they are, unlike photon stops, routinely used in existing machines. Photon stops are the most economical solution because the heat load is extracted at room temperature. They presently consider it most prudent to work with a combined beam screen and photon stop approach, in which the photon stop absorbs most of the SR power, and the beam screen serves only the vacuum purpose. Provided that the recently launched photon stop R and D [10] supports it, we would like to explore solutions with photon stops only. This would allow to reduce the magnet apertures to a certain extent with respect to those required to accommodate high SR power compliant beam screens and reduce cost. The possibility of magnet designs, which have larger vertical apertures where large cooling capillaries can be housed at no additional cost, would allow to soften this statement somewhat and should therefore be pursued as well.
Date: November 21, 2002
Creator: Bauer, P.; Darve, C. & Terechkine, I.
Partner: UNT Libraries Government Documents Department

REFLECTIONS ON MY CONTRIBUTIONS TO PARTICLE PHYSICS AND RECENT EXPERIMENTAL RESULTS FROM RHIC.

Description: My talk today will be composed of two parts. The first part will consist of a summary of some of my experimental contributions over the years. It will not be exhaustive but will highlight the findings that had relevance to the progress of our understanding of particle physics as it has evolved over the years. This section will be divided into three periods: Early, Intermediate and Late, with an in depth discussion of a few of the more significant results. The second part will consist of a discussion of the recently completed Relativistic Heavy Ion Collider (RHIC) machine at Brookhaven National Laboratory (BNL). This will encompass the parameters of the accelerator and some of the interesting and exciting early experimental results emanating from this machine.
Date: January 18, 2002
Creator: SAMIOS,N.P.
Partner: UNT Libraries Government Documents Department

Massively parallel simulation of flow and transport in variably saturated porous and fractured media

Description: This paper describes a massively parallel simulation method and its application for modeling multiphase flow and multicomponent transport in porous and fractured reservoirs. The parallel-computing method has been implemented into the TOUGH2 code and its numerical performance is tested on a Cray T3E-900 and IBM SP. The efficiency and robustness of the parallel-computing algorithm are demonstrated by completing two simulations with more than one million gridblocks, using site-specific data obtained from a site-characterization study. The first application involves the development of a three-dimensional numerical model for flow in the unsaturated zone of Yucca Mountain, Nevada. The second application is the study of tracer/radionuclide transport through fracture-matrix rocks for the same site. The parallel-computing technique enhances modeling capabilities by achieving several-orders-of-magnitude speedup for large-scale and high resolution modeling studies. The resulting modeling results provide many new insights into flow and transport processes that could not be obtained from simulations using the single-CPU simulator.
Date: January 15, 2002
Creator: Wu, Yu-Shu; Zhang, Keni & Pruess, Karsten
Partner: UNT Libraries Government Documents Department

Validation of the RESRAD-RECYCLE computer code.

Description: The RESRAD-RECYCLE computer code was developed by Argonne National Laboratory under the sponsorship of the U.S. Department of Energy. It was designed to analyze potential radiation exposures resulting from the reuse and recycling of radioactively contaminated scrap metal and equipment. It was one of two codes selected in an international model validation study concerning recycling of radioactively contaminated metals. In the validation study, dose measurements at various stages of melting a spent nuclear fuel rack at Studsvik RadWaste AB, Sweden, were collected and compared with modeling results. The comparison shows that the RESRAD-RECYCLE results agree fairly well with the measurement data. Among the scenarios considered, dose results and measurement data agree within a factor of 6. Discrepancies may be explained by the geometrical limitation of the RESRAD-RECYCLE's external exposure model, the dynamic nature of the recycling activities, and inaccuracy in the input parameter values used in dose calculations.
Date: February 1, 2002
Creator: Cheng, J.-J.; Yu, C.; Williams, W. A. & Murphie, W.
Partner: UNT Libraries Government Documents Department

Spin-dependent Forces of Quarks in Baryon

Description: Nonperturbative spin-dependent forces of quarks in a baryon are calculated directly from the QCD Lagrangian in the framework of the Field Correlator Method both for heavy and light quarks. Resulting forces contain terms of 5 different structures, only one being known before in asymptotic form. Perturbative terms obtained by the same method are standard and have different signs and structures with respect to the corresponding nonperturbative ones, implying possible cancellations for some baryonic states.
Date: March 1, 2002
Creator: Simonov, Yu A.
Partner: UNT Libraries Government Documents Department

Reactivity estimation for source-driven systems using first-order perturbation theory.

Description: Applicability of the first-order perturbation (FOP) theory method to reactivity estimation for source-driven systems is examined in this paper. First, the formally exact point kinetics equations have been derived from the space-dependent kinetics equations and the kinetics parameters including the dynamic reactivity have been defined. For the dynamic reactivity, exact and first-order perturbation theory expressions for the reactivity change have been formulated for source-driven systems. It has been also shown that the external source perturbation itself does not change the reactivity if the initial {lambda}-mode adjoint flux is used as the weight function. Using two source-driven benchmark problems, the reactivity change has been estimated with the FOP theory method for various perturbations. By comparing the resulting reactivity changes with the exact dynamic reactivity changes determined from the space-dependent kinetics solutions, it has been shown that the accuracy of the FOP theory method for the accelerator-driven system (ADS) is reasonably good and comparable to that for the critical reactors. The adiabatic assumption has also been shown to be a good approximation for the ADS kinetics analyses.
Date: July 2, 2002
Creator: Kim, Y.; Yang, W. S.; Taiwo, T. A. & Hill, R. N.
Partner: UNT Libraries Government Documents Department