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2-pi Photoproduction from CLAS and CB-ELSA - The Search for Missing Resonances (open access)

2-pi Photoproduction from CLAS and CB-ELSA - The Search for Missing Resonances

2-pi-photoproduction is one of the promising reactions to search for baryon resonances that have been predicted but have not yet been observed. The gamma-rho --> rho-pi{sup 0}-pi{sup 0}(CB-ELSA) and the gamma-rho --> rho-pi{sup +}-pi{sup -} (CLAS) data show interesting resonance structures. A partial wave analysis (PWA) has to be done to determine which baryon resonances contribute what their quantum numbers and their relative couplings to the different accessible rho-2-pi-channels and to the photon are. First preliminary PWA-results on the lowest energy rho-pi{sup 0}-pi{sup 0} data (sq rt s<1.8 GeV)look very promising. From an extension of this analysis to higher energies combining the rho-pi{sup 0}-pi{sup 0} and the rho-pi{sup +}-pi{sup -}-data, one can expect; interesting results on resonances decaying into Delta-pi, N-rho, N(pi-pi)s, N*-pi, and Delta*-pi.
Date: October 1, 2003
Creator: Thoma, Ulrike
Object Type: Article
System: The UNT Digital Library
2002 SITE ENVIRONMENTAL REPORT. (open access)

2002 SITE ENVIRONMENTAL REPORT.

The 2002 Site Environmental Report (SER) is prepared in accordance with DOE Order 231.1, ''Environment, Safety and Health Reporting'', and summarizes the status of Brookhaven National Laboratory's (BNL) environmental programs and performance and restoration efforts, as well as any impacts, both past and present, that Laboratory operations have had on the environment. The document is intended to be technical in nature. A summary of the report is also prepared as a separate document to provide a general overview and includes a CD version of the full report. Operated by Brookhaven Science Associates (BSA) for the Department of Energy (DOE), BNL manages its world-class scientific research with particular sensitivity to environmental and community issues. BNL's motto, ''Exploring Life's Mysteries...Protecting its Future'', reflects BNL's management philosophy to fully integrate environmental stewardship into all facets of its missions, with a health balance between science and the environment.
Date: October 1, 2003
Creator: LABORATORY, BROOKHAVEN NATIONAL
Object Type: Report
System: The UNT Digital Library
Abortion: Legislative Response (open access)

Abortion: Legislative Response

The primary focus of this issue brief is legislative action in the 108th Congress with respect to abortion. However, discussion of those legislative proposals necessarily involves a brief discussion of the leading U.S. Supreme Court decisions concerning a woman’s right to choose whether to terminate her pregnancy. For a more detailed discussion of the relevant case law, see CRS Report 95-724, Abortion Law Development: A Brief Overview.
Date: October 1, 2003
Creator: Lewis, Karen J.; Shimabukuro, Jon O. & Ely, Dana
Object Type: Report
System: The UNT Digital Library
Above- and belowground competition from longleaf pine plantations limits performance of reintroduced herbaceous species. (open access)

Above- and belowground competition from longleaf pine plantations limits performance of reintroduced herbaceous species.

Although overstory trees limit the abundance and species richness of herbaceous vegetation in longleaf pine (Pinus palustris Mill.) plantations, the responsible mechanisms are poorly understood because of confounding among limiting factors. In fall 1998, research was initiated to determine the separate effects of above- and belowground competition and needlefall from overstory pines on understory plant performance. Three 13- to 15-yr-old plantations near Aiken, SC, were thinned to 0, 25, 50, or 100% of nonthinned basal area (19.5 m2 ha-1). Combinations of trenching (to eliminate root competition) and needlefall were applied to areas within each plot, and containerized seedlings of 14 perennial herbaceous species and longleaf pine were planted within each. Overstory crown closure ranged from 0 to 81%, and soil water and available nitrogen varied consistently with pine stocking, trenching, or their combination. Cover of planted species decreased an average of 16.5 and 14.1% as a result of above- and below-ground competition, respectively. Depending on species, needlefall effects were positive, negative, or negligible. Results indicate that understory restoration will be most successful when herbaceous species are established within canopy openings (0.1-0.2 ha) managed to minimize negative effects from above- and belowground competition and needlefall.
Date: October 1, 2003
Creator: Harrington, T. B.; Dagley, C. M. & Edwards., M. B.
Object Type: Article
System: The UNT Digital Library
Acoustic Tests of Small Wind Turbines: Preprint (open access)

Acoustic Tests of Small Wind Turbines: Preprint

Eight small wind turbines ranging from 400 watts to 100 kW in rated power were tested for acoustic emissions at the U.S. Department of Energy's National Renewable Energy Laboratory. Rigorous test procedures based on international standards were followed for measurements and data analyses. Results are presented in the form of sound pressure level versus wind speed, where the sound was recorded downwind of the turbine at a distance equal to the hub height plus half the rotor diameter. When there was sufficient separation between wind turbine noise and background noise, the apparent sound power level was calculated. In several cases, this was not possible. The implications of this problem are discussed briefly. Some of the configurations tested were specifically developed to reduce the noise level of their predecessors. Test data for these machines demonstrate marked progress toward quieter turbines.
Date: October 1, 2003
Creator: Migliore, P.; van Dam, J. & Huskey, A.
Object Type: Article
System: The UNT Digital Library
Active Filter Hardware Design & Performance for the DIII-D Plasma Control System (open access)

Active Filter Hardware Design & Performance for the DIII-D Plasma Control System

OAK-B135 The digital plasma control system (PCS), currently in operation on the DIII-D tokamak, requires inputs from a large number of sensors. Due to the nature of the digitizers and the relative noisy environment from which these signals are derived, each of the 32 signals must be conditioned via an active filter. Two different types of filters, Chebyshev and Bessel with fixed frequencies: 100 Hz Bessel was used for filtering the motional Stark effect diagnostic data. 800 Hz Bessel was designed to filter plasma control data and 1200 Hz Chebyshev is used with closed loop control of choppers. The performance of the plasma control system is greatly influenced by how well the actual filter responses match the software model used in the control system algorithms. This paper addresses the various issues facing the designer in matching the electrical design with the theoretical.
Date: October 1, 2003
Creator: Sellers, D.; Ferron, J. R.; Walker, M. L. & Broesch, J. D.
Object Type: Article
System: The UNT Digital Library
Adaptive Full-Spectrum Solar Energy Systems Cross-Cutting R&D on Adaptive Full Spectrum Solar Energy Systems for More Efficient and Affordable Use of Solar Energy in Buildings and Hybrid Photobioreactors (open access)

Adaptive Full-Spectrum Solar Energy Systems Cross-Cutting R&D on Adaptive Full Spectrum Solar Energy Systems for More Efficient and Affordable Use of Solar Energy in Buildings and Hybrid Photobioreactors

This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports day light from a paraboloidal dish concentrator to a luminaire via a large core polymer fiber optic. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of day lighting and fluorescent lighting for office lighting. In this project, the sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. The secondary mirror consists of eight planar-segmented mirrors that direct the visible part of the spectrum to eight fibers (receiver) and subsequently to eight luminaires. This results in about 8,200 lumens incident at each fiber tip. Each fiber can illuminate about 16.7 m{sup 2} (180 ft{sup 2}) of office space. The IR spectrum is directed to a thermophotovoltaic array to produce electricity. This report emphasizes the design of the thermophotovoltaic receiver and the whole system simulation model.
Date: October 1, 2003
Creator: Wood, Byard D. & Muhs, Jeff D.
Object Type: Report
System: The UNT Digital Library
Adaptive network countermeasures. (open access)

Adaptive network countermeasures.

This report describes the results of a two-year LDRD funded by the Differentiating Technologies investment area. The project investigated the use of countermeasures in protecting computer networks as well as how current countermeasures could be changed in order to adapt with both evolving networks and evolving attackers. The work involved collaboration between Sandia employees and students in the Sandia - California Center for Cyber Defenders (CCD) program. We include an explanation of the need for adaptive countermeasures, a description of the architecture we designed to provide adaptive countermeasures, and evaluations of the system.
Date: October 1, 2003
Creator: McClelland-Bane, Randy; Van Randwyk, Jamie A.; Carathimas, Anthony G. & Thomas, Eric D.
Object Type: Report
System: The UNT Digital Library
The adequacy of current import and export controls on sealed radioactive sources. (open access)

The adequacy of current import and export controls on sealed radioactive sources.

Millions of sealed radioactive sources (SRSs) are being used for a wide variety of beneficial purposes throughout the world. Security experts are now concerned that these beneficial SRSs could be used in a radiological dispersion device to terrorize and disrupt society. The greatest safety and security threat is from those highly radioactive Category 1 and 2 SRSs. Without adequate controls, it may be relatively easy to legally purchase a Category 1 or 2 SRS on the international market under false pretenses. Additionally, during transfer, SRSs are particularly susceptible to theft since the sources are in a shielded and mobile configuration, transportation routes are predictable, and shipments may not be adequately guarded. To determine if government controls on SRS are adequate, this study was commissioned to review the current SRS import and export controls of six countries. Canada, the Russian Federation, and South Africa were selected as the exporting countries, and Egypt, the Philippines, and the United States were selected as importing countries. A detailed review of the controls in each country is presented. The authors found that Canada and Russia are major exporters, and are exporting highly radioactive SRSs without first determining if the recipient is authorized by the receiving …
Date: October 1, 2003
Creator: Longley, Susan W.; Cochran, John Russell; Price, Laura L. (Beta Corporation, Glendale, AZ) & Lipinski, Kendra J.
Object Type: Report
System: The UNT Digital Library
ADVANCED CO2 CYCLE POWER GENERATION (open access)

ADVANCED CO2 CYCLE POWER GENERATION

Research is being conducted under United States Department of Energy (DOE) Contract DE-FC26-02NT41621 to develop a conceptual design and determine the performance characteristics of a new IGCC plant configuration that facilitates CO{sub 2} removal for sequestration. This new configuration will be designed to achieve CO{sub 2} sequestration without the need for water gas shifting and CO{sub 2} separation, and may eliminate the need for a separate sequestration compressor. This research introduces a novel concept of using CO{sub 2} as a working fluid for an advanced coal gasification based power generation system, where it generates power with high system efficiency while concentrating CO{sub 2} for sequestration. This project supports the DOE research objective of development of concepts for the capture and storage of CO{sub 2}.
Date: October 1, 2003
Creator: Nehrozoglu, A.
Object Type: Report
System: The UNT Digital Library
ADVANCED, LOW/ZERO EMISSION BOILER DESIGN AND OPERATION (open access)

ADVANCED, LOW/ZERO EMISSION BOILER DESIGN AND OPERATION

This document reviews the work performed during the quarter July--September 2003. Significant progress has been made in Task 1 (Site Preparation), Task 2 (Test performance) and Task 3 (Techno-Economic Study) of the project: the site preparation has been completed, two weeks of tests have been performed and the power generating units to be compared from an economical standpoint have been selected and accurately described. In the experimental part of this effort (task1), the partners in this project demonstrated the feasibility of 100% air replacement with O{sub 2}-enriched flue gas on 1.5MW coal-fired boiler. The air infiltration have been reduced to approximately 5% of the stoichiometry, enabling to reach around 70% of CO{sub 2} in the flue gases. Higher air in-leakage reduction is expected using alternative boiler operating procedure in order to achieve higher CO{sub 2} concentration in flue gas for further sequestration or reuse. The NO{sub x} emissions have been shown considerably lower in O{sub 2}-fired conditions than in air-baseline, the reduction rate averaging 70%. An additional week of tests is scheduled mid October 2003 for combustion parameter optimization, and some more days of operation will be dedicated to mercury emission measurement and heat transfer characterization. Out of the $485k …
Date: October 1, 2003
Creator: Chatel-Pelage, Fabienne
Object Type: Report
System: The UNT Digital Library
Advanced Processing of CdTe- and CuIn1-xGaxSe2-Based Solar Cells: Final Technical Report, 26 May 1998--22 December 2001 (open access)

Advanced Processing of CdTe- and CuIn1-xGaxSe2-Based Solar Cells: Final Technical Report, 26 May 1998--22 December 2001

This project addresses most of the key CdTe technology areas, with focus on improving the manufacturability and long-term stability of this technology. The activities over this 3-year period include developing simplified processing, studying novel front and back contacts, and improving long-term stability. This report describes work carried out during the last year of the project. The solar cells discussed below are fabricated by various deposition technologies that include chemical vapor deposition, chemical-bath deposition, close-spaced sublimation, and rf-sputtering. The devices are routinely evaluated using standard solar cell analytical techniques such as dark and light current-voltage, spectral response, and capacitance-voltage measurements.
Date: October 1, 2003
Creator: Morel, D. L. & Ferekides, C. S.
Object Type: Report
System: The UNT Digital Library
ADVANCED TURBINE SYSTEM FEDERAL ASSISTANCE PROGRAM (open access)

ADVANCED TURBINE SYSTEM FEDERAL ASSISTANCE PROGRAM

Rolls-Royce Corporation has completed a cooperative agreement under Department of Energy (DOE) contract DE-FC21-96MC33066 in support of the Advanced Turbine Systems (ATS) program to stimulate industrial power generation markets. This DOE contract was performed during the period of October 1995 to December 2002. This final technical report, which is a program deliverable, describes all associated results obtained during Phases 3A and 3B of the contract. Rolls-Royce Corporation (formerly Allison Engine Company) initially focused on the design and development of a 10-megawatt (MW) high-efficiency industrial gas turbine engine/package concept (termed the 701-K) to meet the specific goals of the ATS program, which included single digit NOx emissions, increased plant efficiency, fuel flexibility, and reduced cost of power (i.e., $/kW). While a detailed design effort and associated component development were successfully accomplished for the 701-K engine, capable of achieving the stated ATS program goals, in 1999 Rolls-Royce changed its focus to developing advanced component technologies for product insertion that would modernize the current fleet of 501-K and 601-K industrial gas turbines. This effort would also help to establish commercial venues for suppliers and designers and assist in involving future advanced technologies in the field of gas turbine engine development. This strategy change …
Date: October 1, 2003
Creator: Macri, Frank
Object Type: Report
System: The UNT Digital Library
Algorithm development for Prognostics and Health Management (PHM). (open access)

Algorithm development for Prognostics and Health Management (PHM).

This report summarizes the results of a three-year LDRD project on prognostics and health management. System failure over some future time interval (an alternative definition is the capability to predict the remaining useful life of a system). Prognostics are integrated with health monitoring (through inspections, sensors, etc.) to provide an overall PHM capability that optimizes maintenance actions and results in higher availability at a lower cost. Our goal in this research was to develop PHM tools that could be applied to a wide variety of equipment (repairable, non-repairable, manufacturing, weapons, battlefield equipment, etc.) and require minimal customization to move from one system to the next. Thus, our approach was to develop a toolkit of reusable software objects/components and architecture for their use. We have developed two software tools: an Evidence Engine and a Consequence Engine. The Evidence Engine integrates information from a variety of sources in order to take into account all the evidence that impacts a prognosis for system health. The Evidence Engine has the capability for feature extraction, trend detection, information fusion through Bayesian Belief Networks (BBN), and estimation of remaining useful life. The Consequence Engine involves algorithms to analyze the consequences of various maintenance actions. The Consequence …
Date: October 1, 2003
Creator: Swiler, Laura Painton; Campbell, James E.; Doser, Adele Beatrice & Lowder, Kelly S.
Object Type: Report
System: The UNT Digital Library
Algorithmic support for commodity-based parallel computing systems. (open access)

Algorithmic support for commodity-based parallel computing systems.

The Computational Plant or Cplant is a commodity-based distributed-memory supercomputer under development at Sandia National Laboratories. Distributed-memory supercomputers run many parallel programs simultaneously. Users submit their programs to a job queue. When a job is scheduled to run, it is assigned to a set of available processors. Job runtime depends not only on the number of processors but also on the particular set of processors assigned to it. Jobs should be allocated to localized clusters of processors to minimize communication costs and to avoid bandwidth contention caused by overlapping jobs. This report introduces new allocation strategies and performance metrics based on space-filling curves and one dimensional allocation strategies. These algorithms are general and simple. Preliminary simulations and Cplant experiments indicate that both space-filling curves and one-dimensional packing improve processor locality compared to the sorted free list strategy previously used on Cplant. These new allocation strategies are implemented in Release 2.0 of the Cplant System Software that was phased into the Cplant systems at Sandia by May 2002. Experimental results then demonstrated that the average number of communication hops between the processors allocated to a job strongly correlates with the job's completion time. This report also gives processor-allocation algorithms for minimizing …
Date: October 1, 2003
Creator: Leung, Vitus Joseph; Bender, Michael A. (State University of New York, Stony Brook, NY); Bunde, David P. (University of Illinois, Urbna, IL) & Phillips, Cynthia Ann
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 105, No. 169, Ed. 1 Wednesday, October 1, 2003 (open access)

Altus Times (Altus, Okla.), Vol. 105, No. 169, Ed. 1 Wednesday, October 1, 2003

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: October 1, 2003
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, October 1, 2003 (open access)

The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, October 1, 2003

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: October 1, 2003
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Answering Key Fuel Cycle Questions (open access)

Answering Key Fuel Cycle Questions

The Advanced Fuel Cycle Initiative (AFCI) program has both “outcome” and “process” goals because it must address both waste already accumulating as well as completing the fuel cycle in connection with advanced nuclear power plant concepts. The outcome objectives are waste geological repository capacity and cost, energy security and sustainability, proliferation resistance, fuel cycle economics, and safety. The process objectives are readiness to proceed and adaptability and robustness in the face of uncertainties. A classic decision-making approach to such a multi-attribute problem would be to weight individual quantified criteria and calculate an overall figure of merit. This is inappropriate for several reasons. First, the goals are not independent. Second, the importance of different goals varies among stakeholders. Third, the importance of different goals is likely to vary with time, especially the “energy future.” Fourth, some key considerations are not easily or meaningfully quantifiable at present. Instead, at this point, we have developed 16 questions the AFCI program should answer and suggest an approach of determining for each whether relevant options improve meeting each of the program goals. We find that it is not always clear which option is best for a specific question and specific goal; this helps identify key …
Date: October 1, 2003
Creator: Piet, Steven J.; Dixon, Brent W.; Herring, J. Stephen; Shropshire, David E. & Dunzik-Gougar, Mary Lou
Object Type: Article
System: The UNT Digital Library
The Archer Advocate (Holliday, Tex.), Vol. 1, No. 26, Ed. 1 Wednesday, October 1, 2003 (open access)

The Archer Advocate (Holliday, Tex.), Vol. 1, No. 26, Ed. 1 Wednesday, October 1, 2003

Weekly newspaper from Holliday, Texas that includes local, state, and national news along with advertising.
Date: October 1, 2003
Creator: Thomas, John
Object Type: Newspaper
System: The Portal to Texas History
Architectural requirements for the Red Storm computing system. (open access)

Architectural requirements for the Red Storm computing system.

This report is based on the Statement of Work (SOW) describing the various requirements for delivering 3 new supercomputer system to Sandia National Laboratories (Sandia) as part of the Department of Energy's (DOE) Accelerated Strategic Computing Initiative (ASCI) program. This system is named Red Storm and will be a distributed memory, massively parallel processor (MPP) machine built primarily out of commodity parts. The requirements presented here distill extensive architectural and design experience accumulated over a decade and a half of research, development and production operation of similar machines at Sandia. Red Storm will have an unusually high bandwidth, low latency interconnect, specially designed hardware and software reliability features, a light weight kernel compute node operating system and the ability to rapidly switch major sections of the machine between classified and unclassified computing environments. Particular attention has been paid to architectural balance in the design of Red Storm, and it is therefore expected to achieve an atypically high fraction of its peak speed of 41 TeraOPS on real scientific computing applications. In addition, Red Storm is designed to be upgradeable to many times this initial peak capability while still retaining appropriate balance in key design dimensions. Installation of the Red Storm …
Date: October 1, 2003
Creator: Camp, William J. & Tomkins, James Lee
Object Type: Report
System: The UNT Digital Library
ASHRAE and residential ventilation (open access)

ASHRAE and residential ventilation

In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the …
Date: October 1, 2003
Creator: Sherman, Max H.
Object Type: Article
System: The UNT Digital Library
Assessing mesoscale material response under shock & isentropic compression via high-resolution line-imaging VISAR. (open access)

Assessing mesoscale material response under shock & isentropic compression via high-resolution line-imaging VISAR.

Of special promise for providing dynamic mesoscale response data is the line-imaging VISAR, an instrument for providing spatially resolved velocity histories in dynamic experiments. We have prepared two line-imaging VISAR systems capable of spatial resolution in the 10-20 micron range, at the Z and STAR facilities. We have applied this instrument to selected experiments on a compressed gas gun, chosen to provide initial data for several problems of interest, including: (1) pore-collapse in copper (two variations: 70 micron diameter hole in single-crystal copper) and (2) response of a welded joint in dissimilar materials (Ta, Nb) to ramp loading relative to that of a compression joint. The instrument is capable of resolving details such as the volume and collapse history of a collapsing isolated pore.
Date: October 1, 2003
Creator: Hall, Clint Allen; Furnish, Michael David; Podsednik, Jason W.; Reinhart, William Dodd; Trott, Wayne Merle & Mason, Joshua
Object Type: Report
System: The UNT Digital Library
ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL (open access)

ASSESSMENT OF LOW COST NOVEL SORBENTS FOR COAL-FIRED POWER PLANT MERCURY CONTROL

This is a Technical Report under a program funded by the Department of Energy's National Energy Technology Laboratory (NETL) to obtain the necessary information to assess the viability of lower cost alternatives to commercially available activated carbon for mercury control in coal-fired utilities. Tests and analysis on samples from Powerton and Valley to yield waste characterization results for the COHPAC long-term tests were conducted. A draft final report for the sorbent evaluations at Valley was submitted. Presentations of the results for this program were given at two conferences. A test plan for sorbent evaluations at We Energies' Pleasant Prairie Power Plant was drafted. Work will begin mid October 2003. A no cost time extension for work to be completed by December 31, 2003 was granted by DOE/NETL.
Date: October 1, 2003
Creator: Ley, Trevor
Object Type: Report
System: The UNT Digital Library
Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts (open access)

Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts

Sargent and Lundy LLC conducted an independent analysis of parabolic trough and power tower solar technology cost and performance.
Date: October 1, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library