Search for simultaneous optical counterparts of gamma-ray bursts (open access)

Search for simultaneous optical counterparts of gamma-ray bursts

Gamma Ray Bursts (GRBs) are brief, randomly located, releases of gamma-ray energy from unknown celestial sources that occur almost daily. The study of GRBs has undergone a revolution in the past three years due to an international effort of follow-up observations made possible by the instantaneous distribution of reliable GRB coordinate information over the internet provided by NASA's GCN (GRB Coordinates Network). The 3-year LDRD project described here, done in collaboration with the workers responsible for the GCN, was the very first serious system to actively utilize the GCN and thus played a major role in the development of the GCN and the dramatic increase in our understanding of GRBs. The scientific objective of this project was to measure the intensity of any prompt visible radiation accompanying the gamma-ray emission utilizing a small but sensitive robotic telescope that responded to GCN triggers by rapidly taking images of the GCN error box. The instrument developed for this project, LOTIS, was the first of its kind, and the longest running, collecting data on over 75 GRBs during its 3 year running period. The results of LOTIS and the other follow-up programs have now shown that GRBs are at cosmological distances and interact …
Date: September 5, 2000
Creator: Park, H. S.; Porrata, R. A.; Bionta, R. M. & Williams, G. G.
Object Type: Report
System: The UNT Digital Library
Post-Remediation Biomonitoring of Pesticides in Marine Waters Near the United Heckathorn Site, Richmond, California (open access)

Post-Remediation Biomonitoring of Pesticides in Marine Waters Near the United Heckathorn Site, Richmond, California

Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in January 1998 from four stations near Lauritzen Canal in Richmond, California, for the first post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and DDT were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared to pre-remediation data available from the California State Mussel Watch program (tissues) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Biomonitoring results indicated that pesticides were still bioavailable in the water column, and have not been reduced from pre-remediation levels. Annual biomonitoring will continue to assess the effectiveness of remedial actions at the United Heckathorn Site.
Date: September 5, 2000
Creator: Antrim, Liam D. & Kohn, Nancy P.
Object Type: Report
System: The UNT Digital Library
Fracture Geometry Analysis for the Stratigraphic Units of the Repository Host Horizon (open access)

Fracture Geometry Analysis for the Stratigraphic Units of the Repository Host Horizon

None
Date: September 5, 2000
Creator: Hardin, E.
Object Type: Report
System: The UNT Digital Library
Economic Indicators: Country Comparisons (open access)

Economic Indicators: Country Comparisons

None
Date: September 5, 2000
Creator: Waddoups, Shawn
Object Type: Report
System: The UNT Digital Library
Shallow Cavity Flow Tone Experiments: Onset of Locked-On States (open access)

Shallow Cavity Flow Tone Experiments: Onset of Locked-On States

Fully turbulent inflow past a shallow cavity is investigated for the configuration of an axisymmetric cavity mounted in a pipe. Emphasis is on conditions giving rise to coherent oscillations, which can lead to locked-on states of flow tones in the pipe-cavity system. Unsteady surface pressure measurements are interpreted using three-dimensional representations of amplitude-frequency-inflow velocity; these representations are constructed for a range of cavity depth. Assessment of these data involves a variety of approaches. Evaluation of pressure gradients on plan views of the three-dimensional representations allows extraction of the frequencies of the instability (Strouhal) modes of the cavity oscillation. These frequency components are correlated with traditional models originally formulated for cavities in a free-stream. In addition, they are normalized using two length scales; inflow boundary-layer thickness and pipe diameter. These scales are consistent with those employed for the hydrodynamic instability of the separated shear layer, and are linked to the large-scale mode of the shear layer oscillation, which occurs at relatively long cavity length. In fact, a simple scaling based on pipe diameter can correlate the frequencies of the dominant peaks over a range of cavity depth. The foregoing considerations provide evidence that pronounced flow tones can be generated from a …
Date: September 5, 2000
Creator: Rockwell, D.; Lin, J. C.; Oshkai, P.; Reiss, M. & Pollack, M.
Object Type: Report
System: The UNT Digital Library
Local Exhaust System Fans and Fan Motors and Backdraft Dampers and Isolation Dampers (open access)

Local Exhaust System Fans and Fan Motors and Backdraft Dampers and Isolation Dampers

None
Date: September 5, 2000
Creator: Van Katwijk, Carl
Object Type: Report
System: The UNT Digital Library
Failure and Reliability Analysis for the Master Pump Shutdown System (open access)

Failure and Reliability Analysis for the Master Pump Shutdown System

The Master Pump Shutdown System (MPSS) will be installed in the 200 Areas of the Hanford Site to monitor and control the transfer of liquid waste between tank farms and between the 200 West and 200 East areas through the Cross-Site Transfer Line. The Safety Function provided by the MPSS is to shutdown any waste transfer process within or between tank farms if a waste leak should occur along the selected transfer route. The MPSS, which provides this Safety Class Function, is composed of Programmable Logic Controllers (PLCs), interconnecting wires, relays, Human to Machine Interfaces (HMI), and software. These components are defined as providing a Safety Class Function and will be designated in this report as MPSS/PLC. Input signals to the MPSS/PLC are provided by leak detection systems from each of the tank farm leak detector locations along the waste transfer route. The combination of the MPSS/PLC, leak detection system, and transfer pump controller system will be referred to as MPSS/SYS. The components addressed in this analysis are associated with the MPSS/SYS. The purpose of this failure and reliability analysis is to address the following design issues of the Project Development Specification (PDS) for the MPSS/SYS (HNF 2000a): (1) Single …
Date: September 5, 2000
Creator: BEVINS, R.R.
Object Type: Report
System: The UNT Digital Library
Software Verification and Validation Test Report for the HEPA filter Differential Pressure Fan Interlock System (open access)

Software Verification and Validation Test Report for the HEPA filter Differential Pressure Fan Interlock System

The HEPA Filter Differential Pressure Fan Interlock System PLC ladder logic software was tested using a Software Verification and Validation (V&V) Test Plan as required by the ''Computer Software Quality Assurance Requirements''. The purpose of his document is to report on the results of the software qualification.
Date: September 5, 2000
Creator: ERMI, A.M.
Object Type: Report
System: The UNT Digital Library
Unistrut plan in metal channel including nuts, straps and clamps (open access)

Unistrut plan in metal channel including nuts, straps and clamps

None
Date: September 5, 2000
Creator: Van Katwijk, Carl
Object Type: Report
System: The UNT Digital Library
NREL Advanced Research Turbine (ART) Aerodynamic Design of ART-2B Rotor Blades (open access)

NREL Advanced Research Turbine (ART) Aerodynamic Design of ART-2B Rotor Blades

The National Renewable Energy Laboratory (NREL) installed two Advanced Research Turbines (ART) at the National Wind Technology Center near Boulder, Colorado, to use as full-scale test beds for ongoing research efforts, including three-dimensional blade aerodynamics and the effects of various control methods on turbine loads and performance. The Westinghouse WWG-0600 was selected as a baseline configuration for the ART turbines. The first turbine, ART-1, is currently operational and has been used to collect a baseline set of performance and loads data. A second turbine, ART-2A, incorporates several major modifications and may be upgraded further to a configuration designated aRT-2B. Possible features of the ART-2B turbine include a multi-degree of freedom hum and newly designed rotor blades. Global energy concepts, L.L.C. provided engineering support to NREL in designing the components for the ART-2B turbine. This document provides a summary of work performed by GEC on the aerodynamic design of ART-2B rotor blades.
Date: September 5, 2000
Creator: Griffin, D.A.
Object Type: Report
System: The UNT Digital Library
High-power fast RF ferrite phase shifter. (open access)

High-power fast RF ferrite phase shifter.

None
Date: September 5, 2000
Creator: Kang, Y.
Object Type: Article
System: The UNT Digital Library
The representation of numbers by states in quantum mechanics. (open access)

The representation of numbers by states in quantum mechanics.

None
Date: September 5, 2000
Creator: Benioff, P.
Object Type: Article
System: The UNT Digital Library
Guidance on Dose Rate Measurements for Use in Dose-to-Curie Conversions (open access)

Guidance on Dose Rate Measurements for Use in Dose-to-Curie Conversions

The dose-to-curie (DTC) methodology used at SRS was developed in early 1994 by Health Physics Technology (HPT) for inclusion in the Site Waste Information Tracking System (WITS). DTC is used to estimate the nuclide activity in a waste container based on the measured dose rate from the container. The DTC method is a simple and easy to apply method that can provide a reasonable estimate of the container activity by nuclide when properly applied. In order to make the method practical, numerous assumptions had to be made and limitations placed on its use. Many of these assumptions and limitations can only be procedurally controlled and must be well understood by these individuals in order to assure proper application numerous the method. These limitations are addressed in this report.
Date: September 5, 2000
Creator: Howell, R.S.
Object Type: Report
System: The UNT Digital Library
Post-Remediation Biomonitoring of Pesticides in Marine Waters Near the United Heckathorn Superfund Site, Richmond, California (open access)

Post-Remediation Biomonitoring of Pesticides in Marine Waters Near the United Heckathorn Superfund Site, Richmond, California

This report, PNNL-11911 Rev. 1, was published in July 2000 and replaces PNNL-11911, which was published in September 1998. The revision corrects tissue concentration units that were reported as dry weight but were actually wet weight, and updates conclusions based on the correct reporting units. Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in January 1998 from four stations near Lauritzen Canal in Richmond, California, for the first post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and DDT were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared to pre-remediation data available from the California State Mussel Watch program (tissues) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Chlorinated pesticide concentrations in water samples were similar to pre-remediation levels and did not meet remediation goals. Mean dieldrin concentrations in water ranged from 0.65 ng/L to 18.1 ng/L and were higher than the remediation goal (0.14 ng/L) at all stations. Mean total DDT concentrations in …
Date: September 5, 2000
Creator: Antrim, LD & Kohn, NP
Object Type: Report
System: The UNT Digital Library
Initial Application of the FEMP Measurement and Verification Guidelines in Super ESPC Delivery Orders: Final Report; May 2000 (open access)

Initial Application of the FEMP Measurement and Verification Guidelines in Super ESPC Delivery Orders: Final Report; May 2000

Schiller Associates examined the measurement and verification (M and V) plans and activities for seven Western Region Super Energy Savings Performance Contract (ESPC) projects to learn how federal agencies are implementing M and V and what factors influence M and V plan development. This report describes the method used to examine the M and V plans and presents the findings. The goals were to find common factors that influenced M and V plan development and implementation, assess risks to the agency as a result of particular M and V plans, and develop recommendations for improving M and V plan development and implementation. Participating agencies and sites were: (1) National Park Service, Yosemite National Park, CA; (2) Veterans Affairs, VA Medical Center, San Francisco, CA; (3) US Forest Service, USFS Laboratory, Corvallis, OR; (4) Federal Aviation Administration, ATRCC, Auburn, WA; (5) US Department of Defense, Defense Manpower Data Center, Monterey, CA; (6) US Coast Guard, Coast Guard Station, Alameda, CA; and (7) US Navy, Pt. Mugu, Oxnard, CA.
Date: September 5, 2000
Creator: Jump, D. & Stetz, M.
Object Type: Report
System: The UNT Digital Library
DISCO: An object-oriented system for music composition and sound design (open access)

DISCO: An object-oriented system for music composition and sound design

This paper describes an object-oriented approach to music composition and sound design. The approach unifies the processes of music making and instrument building by using similar logic, objects, and procedures. The composition modules use an abstract representation of musical data, which can be easily mapped onto different synthesis languages or a traditionally notated score. An abstract base class is used to derive classes on different time scales. Objects can be related to act across time scales, as well as across an entire piece, and relationships between similar objects can replicate traditional music operations or introduce new ones. The DISCO (Digital Instrument for Sonification and Composition) system is an open-ended work in progress.
Date: September 5, 2000
Creator: Kaper, H. G.; Tipei, S. & Wright, J. M.
Object Type: Article
System: The UNT Digital Library
Charged pion electroproduction on H,{sup 2}H, and {sup 3}He. (open access)

Charged pion electroproduction on H,{sup 2}H, and {sup 3}He.

None
Date: September 5, 2000
Creator: Jackson, H. E.
Object Type: Article
System: The UNT Digital Library
Compilation of Data on Radionuclide Data for Specific Activity, Specific Heat and Fission Product Yields (open access)

Compilation of Data on Radionuclide Data for Specific Activity, Specific Heat and Fission Product Yields

This compilation was undertaken to update the data used in calculation of curie and heat loadings of waste containers in the Solid Waste Management Facility. The data has broad general use and has been cross-checked extensively in order to be of use in the Materials Accountability arena. The fission product cross-sections have been included because they are of use in the Environmental Remediation and Waste Management areas where radionuclides which are not readily detectable need to be calculated from the relative fission yields and material dispersion data.
Date: September 5, 2000
Creator: Gibbs, A. & Thomason, R.S.
Object Type: Report
System: The UNT Digital Library
General Design of the Layout for New Undulator-Only Beamline Front Ends (open access)

General Design of the Layout for New Undulator-Only Beamline Front Ends

Optical and ray-tracing analysis of the new APS front ends for undulator-only operation are presented.
Date: September 5, 2000
Creator: Shu, Deming; Ramanathan, Mohan & Kuzay, Tuncer M.
Object Type: Article
System: The UNT Digital Library
Network Algorithms for Minimum Energy Fracture Surfaces (open access)

Network Algorithms for Minimum Energy Fracture Surfaces

None
Date: September 5, 2000
Creator: HOLM,ELIZABETH A. & MCGOVNEY,GARY N.
Object Type: Article
System: The UNT Digital Library
Advanced Processing of CdTe- and CuIn{sub x}Ga{sub 1{minus}x}Se{sub 2}-Based Solar Cells; Phase I Report (open access)

Advanced Processing of CdTe- and CuIn{sub x}Ga{sub 1{minus}x}Se{sub 2}-Based Solar Cells; Phase I Report

The main tasks of the cadmium telluride portion of this project include the development of simplified processing for fabricating high-efficiency CdTe solar cells, studies on the long-term stability of CdTe devices, and the development of alternative transparent conducting oxides, window layers, and back contacts. The second portion of this project focused on CIGS solar cells. The main tasks include the development of a manufacturable process for CIGS devices and the development of high-band-gap alloys for use in tandem cell structures. Additional objectives include development of improved junction formation processing and contributing to the overall understanding of these materials and devices. Because the processing is manufacturing-driven, the authors use an all solid-state, simplified two-step process that relaxes the level of deposition control required.
Date: September 5, 2000
Creator: Morel, D. L. & Ferekides, C. S.
Object Type: Report
System: The UNT Digital Library
Review of Operation and Maintenance Experience in the DOE-EPRI Wind Turbine Verification Program (open access)

Review of Operation and Maintenance Experience in the DOE-EPRI Wind Turbine Verification Program

All the projects within the US Department of Energy (DOE) Electrical Power Research Institute (EPRI) Wind Turbine Verification Program (TVP) are now in operation. As a result, the emphasis of the owners and operators has shifted from installation and commissioning to a focus on optimizing the operation and maintenance (O and M) activities of the projects. Each project utilizes a unique strategy for performing O and M. O and M personnel for projects in Searsburg, Vermont; Glenmore, Wisconsin; Algona, Iowa; Springview, Nebraska; Kotzebue, Alaska; and Big Spring, Texas include on-site vendor representatives, dedicated utility personnel, and utility personnel who split their time between the wind turbines and other utility responsibilities. Each project has its own set of priorities for balancing turbine availability against safety, minimizing overtime pay, and other utility responsibilities. Various strategies have also been employed to ensure access to tools and spare parts. This paper compares and contrasts the various O and M strategies at TVP projects and reviews the causes of turbine downtime and the frequency and duration of faults.
Date: September 5, 2000
Creator: Conover, K.; VandenBosche, J.; Rhoads, H. (Global Energy Concepts, LLC) & Smith, B. (National Renewable Energy Laboratory)
Object Type: Article
System: The UNT Digital Library
Task III: UCSD/DIII-D/Textor FY-97-98 Accomplishments (open access)

Task III: UCSD/DIII-D/Textor FY-97-98 Accomplishments

OAK (B204) Task III: UCSD/DIII-D/Textor FY-97-98 Accomplishments. A comprehensive report on the physics of pump limiters and particularly, the characterization of ALT-II, was published in Nuclear Fusion, bringing the project to a closure. The performance of the toroidal pump limiter was characterized under full auxiliary heating of 7 MW of NBI and ICRH and full pumping, as stated in the project milestones. Relevant highlights are: (1) Pumping with ALT-II allows for density control. (2) The achieved exhaust efficiency is 4% during NBI operation and near 2% during OH or ICRH operation. (3) We have shown that an exhaust efficiency of 2% is sufficient to satisfy the ash removal requirements of fusion reactors. (4) The plasma particle efflux and the pumped flux both increase with density and heating power. (5) The particle confinement time is less than the energy confinement time by a factor of 4. In summary, pumped belt limiters could provide the density control and ash exhaust requirements of fusion reactors.
Date: September 5, 2000
Creator: Boedo, J.A.
Object Type: Report
System: The UNT Digital Library
Characterization Activities to Determine the Extent of DNAPL in the Vadose Zone at the A-014 Outfall of A/M Area (open access)

Characterization Activities to Determine the Extent of DNAPL in the Vadose Zone at the A-014 Outfall of A/M Area

The purpose of this investigation was to perform characterization activities necessary to confirm the presence and extent of DNAPL in the shallow vadose zone near the headwaters of the A-014 Outfall. Following the characterization, additional soil vapor extraction wells and vadose monitoring probes were installed to promote and monitor remediation activities in regions of identified DNAPL.
Date: September 5, 2000
Creator: Jackson, D. G.
Object Type: Report
System: The UNT Digital Library