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EVALUATING ENVIRONMENTAL DECISION SUPPORT TOOLS. (open access)

EVALUATING ENVIRONMENTAL DECISION SUPPORT TOOLS.

Effective contaminated land management requires a number of decisions addressing a suite of technical, economic, and social concerns. These concerns include human health risks, ecological risks, economic costs, technical feasibility of proposed remedial actions, and the value society places on clean-up and re-use of formerly contaminated lands. Decision making, in the face of uncertainty and multiple and often conflicting objectives, is a vital and challenging role in environmental management that affects a significant economic activity. Although each environmental remediation problem is unique and requires a site-specific analysis, many of the key decisions are similar in structure. This has led many to attempt to develop standard approaches. As part of the standardization process, attempts have been made to codify specialist expertise into decision support tools. This activity is intended to facilitate reproducible and transparent decision making. The process of codifying procedures has also been found to be a useful activity for establishing and rationalizing management processes. This study will have two primary objectives. The first is to develop taxonomy for Decision Support Tools (DST) to provide a framework for understanding the different tools and what they are designed to address in the context of environmental remediation problems. The taxonomy will have …
Date: October 1, 2004
Creator: SULLIVAN, T.
System: The UNT Digital Library
Field Verification Project for Small Wind Turbines, Quarterly Report, October-December 2001, 4th Quarter, Issue No.7 (open access)

Field Verification Project for Small Wind Turbines, Quarterly Report, October-December 2001, 4th Quarter, Issue No.7

This newsletter provides a brief overview of the Field Verification Project for Small Wind Turbines conducted at the NWTC, along with a description of activities and case studies of projects.
Date: December 1, 2004
Creator: unknown
System: The UNT Digital Library
Gridley Ethanol Demonstration Project Utilizing Gasification Technology: Feedstock Supply Plan; March 15, 2004 (open access)

Gridley Ethanol Demonstration Project Utilizing Gasification Technology: Feedstock Supply Plan; March 15, 2004

The report describes a Feedstock Supply Plan for the proposed Gridley Ethanol Demonstration Project to be located in the City of Gridley Industrial Park in Gridley, California. This report also includes information on the establishment of the required infrastructure required for collecting approximately 113,000 Bone Dry Tons (BDT) annually for the proposed facility. Using the Pearson Technology from Aberdeen, Mississippi, and the related engineering assumptions for required feedstock, it is estimated that the proposed Gridley Ethanol Project will use approximately 113,000 BDT of rice straw to produce approximately up to 20 million gallons of ethanol annually, and/or process steam and or electricity. Based on TSS's survey of planted rice acreage in the Sacramento Valley, a total of 379,765 acres of rice are grown within a 30-mile radius of the Gridley site and that 759,530 BDT of recoverable rice straw are generated annually. This volume of rice straw is 6.7 times the 113,000 BDT of tot al feedstock needed by the proposed Gridley facility. Sufficient infrastructure exists with additional market potential for further private market infrastructure expansion in California and the Northwest (Oregon, Washington and Idaho) to collect the annual feedstock requirement of 113,000 BDT for the proposed Gridley Ethanol Demonstration …
Date: July 1, 2004
Creator: unknown
System: The UNT Digital Library
DOE Hydrogen Program 2004 Annual Merit Review and Peer Evaluation Report (open access)

DOE Hydrogen Program 2004 Annual Merit Review and Peer Evaluation Report

This document summarizes the project evaluations and comments from the DOE Hydrogen Program 2004 Annual Program Review. Hydrogen production, delivery and storage; fuel cells; technology validation; safety, codes and standards; and education R&D projects funded by DOE in FY2004 are reviewed.
Date: October 1, 2004
Creator: unknown
System: The UNT Digital Library
Preliminary Structural Design of Composite Blades for Two- and Three-Blade Rotors (open access)

Preliminary Structural Design of Composite Blades for Two- and Three-Blade Rotors

A computerized method has been developed to aid in the preliminary design of composite wind turbine blades. The method allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. Given the blade external geometry description and its design load distribution, the Fortran code uses ultimate-strength and buckling-resistance criteria to compute the design thickness of load-bearing composite laminates. The code also includes an analysis option to obtain blade properties if a composite laminates schedule is prescribed. These properties include bending stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Nonstructural materials-gelcoat, nexus, and bonding adhesive-are also included for computation of mass. The code includes an option to format the output properties that can be directly input to advanced aeroelastic codes. This report summarizes the structural layout of composite laminates within the blade, the design approach, and the computational process. Finally, we present the results of two composite blades designed using this code in support of a project covering comparison of two- and three-blade rotors for a hypothetical turbine.
Date: September 1, 2004
Creator: Bir, G. & Migliore, P.
System: The UNT Digital Library
Study and Development of Anti-Islanding Control for Grid-Connected Inverters (open access)

Study and Development of Anti-Islanding Control for Grid-Connected Inverters

This is a report on the development of anti-islanding control for grid-connected inverters from distributed generation sources. Islanding occurs when a distributed generation source continues to provide electricity to a portion of the utility grid after the utility experiences a disruption in service. Since the utility no longer controls this part of the distribution system, islanding can pose problems for utility personnel safety, power quality, equipment damage, and restoration of service. This report proposes a new family of anti-islanding schemes that meet IEEE 1547 interconnection standards, that can detect all disruptions in service, have minimum power-quality impact, require low-cost implementation, work for multiple distributed generators, and work for any multi-phase inverters. It also provides design guidelines for the schemes, and evaluates and validates the proposed schemes for practical applications.
Date: May 1, 2004
Creator: Ye, Z.; Walling, R.; Garces, L.; Zhou, R.; Li, L. & Wang, T.
System: The UNT Digital Library
Investigation of Gettering Mechanisms in Crystalline Silicon: Final Subcontract Report, 21 July 1997--30 September 2003 (open access)

Investigation of Gettering Mechanisms in Crystalline Silicon: Final Subcontract Report, 21 July 1997--30 September 2003

In this investigation, various aspects of the mechanisms of gettering contaminant impurities away from device active regions in Si have been systematically conducted. Also systematically studied are the modeling of electrical activity of metallic precipitates in Si based on the Schottky effect. With these studies, our knowledge of gettering in Si and on the electrical activity of metallic precipitates in Si has become substantially complete in the sense that interpretations of major experimental results have become self- and mutually consistent. The purpose of conducting the studies supported by this project was to obtain consistent interpretations of existing experimental results, as well as to conduct the needed new experiments, concerning the various phenomena associated with gettering in Si. The investigated gettering method is that by using an Al layer, and the involved works span from studies concerning basic point defect behaviors during gettering to studies of application of the gettering method to improve multicrystalline Si minority-carrier diffusion lengths. A preliminary study of the effect of gettering in affecting the solar cell efficiency has been conducted. Moreover, a study of the electrical behavior of precipitated metallic impurities in Si based on the Schottky property of the precipitates, which is a newly proposed …
Date: May 1, 2004
Creator: Tan, T. Y.
System: The UNT Digital Library
Early LLNL Application Scaling Results on BlueGene/L (open access)

Early LLNL Application Scaling Results on BlueGene/L

Miranda is a high order hydrodynamics code for computing fluid instabilities and turbulent mixing. It employs FFTs and band-diagonal matrix solvers for computing spectrally-accurate derivatives, combined with high-order integration methods for time advancement; e.g., fourth-order Runge-Kutta. Fluid properties, i.e., viscosity, diffusivity and thermal conductivity, are computed from kinetic theory. The code contains solvers for both compressible and incompressible flows. It has been used primarily for studying Rayleigh-Taylor (R-T) and Richtmyer-Meshkov (R-M) instabilities, which occur in supernovae and Inertial Confinement Fusion (ICF).
Date: November 1, 2004
Creator: Cook, A. W.; Greenough, J. A.; Gygi, F.; Streitz, F. H.; Kubota, A.; Bulatov, V. V. et al.
System: The UNT Digital Library
Estimate of the energy spread in a booster cycle via the bunch length measurement (open access)

Estimate of the energy spread in a booster cycle via the bunch length measurement

It is important for us to obtain the information of energy spread vs. time in a Booster cycle via the same beam event, for the purpose of minimizing the error caused by the cycle-to-cycle fluctuation. The bunch length (BL) can be extracted from the resistive wall signal (RWS) at different times of a Booster cycle, and from which the energy spread can be estimated.
Date: November 1, 2004
Creator: Yang, Xi
System: The UNT Digital Library
Evaluation of the Geothermal Public Power Utility Workshops in California (open access)

Evaluation of the Geothermal Public Power Utility Workshops in California

The federal government devotes significant resources to educating consumers and businesses about geothermal energy. Yet little evidence exists for defining the kinds of information needed by the various audiences with specialized needs. This paper presents the results of an evaluation of the Geothermal Municipal Utility Workshops that presented information on geothermal energy to utility resource planners at customer-owned utilities in California. The workshops were sponsored by the Western Area Power Administration and the U.S. Department of Energy's GeoPowering the West Program and were intended to qualitatively assess the information needs of municipal utilities relative to geothermal energy and get feedback for future workshops. The utility workshop participants found the geothermal workshops to be useful and effective for their purposes. An important insight from the workshops is that utilities need considerable lead-time to plan a geothermal project. They need to know whether it is better to own a project or to purchase geothermal electricity from another nonutility owner. California customer-owned utilities say they do not need to generate more electricity to meet demand, but they do need to provide more electricity from renewable resources to meet the requirements of the state's Renewable Portfolio Standard.
Date: October 1, 2004
Creator: Farhar, B. C.
System: The UNT Digital Library
Specific PVMaT R&D in CdTe Product Manufacturing: Final Subcontract Report, March 2003 (open access)

Specific PVMaT R&D in CdTe Product Manufacturing: Final Subcontract Report, March 2003

Results of a 3+ year subcontract are presented. The research was conducted under Phase 5A2 of the subcontract. The three areas of effort in the subcontract were (1) manufacturing line improvements, (2) product readiness, and (3) environmental, safety, and health programs. The subcontract consisted of three phases, approximately 1 year each. Phase I included the development, design, and implementation of a high-throughput, low-cost lamination process. This goal was achieved using the support of key experts such as Automation and Robotics Research Institute (ARRI) to identify appropriate lamination equipment vendors, and material handling. Product designs were reviewed by Arizona State University Photovoltaic Testing Laboratory and Underwriters Laboratories. Modifications to the module designs were implemented to meet future testing requirements. A complete review of the Environmental, Health, and Safety programs was conducted, along with training by the Environmental Protection Agency (EP A) and Occupational Safety and Health Administration (OSHA). Work conducted during Phase II included the implementation of an improved potting procedure for the wiring junction. The design of the equipment focused on high-throughput, low-cost operations. During Phase III , First Solar made significant progress in three areas: Manufacturing Readiness; Product Performance; and Environmental, Health, and Safety (EH&S). First Solar's accomplishments in …
Date: January 1, 2004
Creator: Bohland, J.; McMaster, A.; Henson, S. & Hanak, J.
System: The UNT Digital Library
Prevention of Prespawning Mortality: Cause of Salmon Headburns and Cranial Lesions (open access)

Prevention of Prespawning Mortality: Cause of Salmon Headburns and Cranial Lesions

This project was to undertaken to provide information about a condition known as ''headburn''. Information from the project will enable U.S. Corps of Engineers managers to make adjustments in operational procedures or facilities on the Columbia and Snake rivers to prevent loss of pre-spawning adult salmonids that migrate through the facilities. Headburn is a descriptive clinical term used by fishery biologists to describe scalping or exfoliation of skin and ulceration of underlying connective tissue and muscle, primarily of the jaw and cranial region of salmonids observed at fish passage facilities. Headburn lesions are primarily caused when fish collide with concrete or other structures at dams and fish passage facilities, and may be exacerbated in some fish that ''fallback'' or pass over spillways or through turbine assemblies after having passed the dam through a fish ladder. Prespawning mortality of headburned salmonids can be prevented or greatly reduced by therapeutic treatment of both hatchery and wild fish. Treatments would consist of topical application of an anti-fungal agent, injection of replacement plasma electrolytes into the peritoneal cavity, and injection of a broad-spectrum antibacterial agent at fish passage and trapping facilities or hatcheries.
Date: June 1, 2004
Creator: Neitzel, Duane A.; Elston, R A. & Abernethy, Cary S.
System: The UNT Digital Library
A Measurement of the Top Quark Mass with the D0 Detector at s**(1/2) = 1.96-TeV using the Matrix Element Method (open access)

A Measurement of the Top Quark Mass with the D0 Detector at s**(1/2) = 1.96-TeV using the Matrix Element Method

Using a data set of 158 and 169 pb{sup -1} of D0 Run-II data in the electron and muon plus jets channel, respectively, the top quark mass has been measured using the Matrix Element Method. The method and its implementation are described. Its performance is studied in Monte Carlo using ensemble tests and the method is applied to the Moriond 2004 data set.
Date: April 1, 2004
Creator: Kroeninger, Kevin Alexander
System: The UNT Digital Library
Trajectory Oriented and Fault Tolerant Based Intelligent Process Control for Flexible CIGS PV Module Manufacturing: Phase 1 Final Technical Report, March 2003 (open access)

Trajectory Oriented and Fault Tolerant Based Intelligent Process Control for Flexible CIGS PV Module Manufacturing: Phase 1 Final Technical Report, March 2003

With the assistance of NREL's PV Manufacturing R&D program, ITN Energy Systems, Inc. and Global Solar Energy, Inc. continued the advancement of CIGS production technology by developing trajectory-oriented predictive/control models, fault-tolerance control, control-platform development, in-situ sensors, and process improvements. Modeling activities to date include developing physics-based and empirical models for CIGS and physics-based Mo deposition processing, implementing model-based control for CIGS processing, and applying predictive models to the construction of new evaporation sources. Model-based control is enabled by implementing reduced or empirical models into a control platform. Reliability improvement activities include systematic development of fault-prevention procedures (e.g., preventative maintenance schedules) and detection/reconfiguration of sensor and other hardware failures for the full range of CIGS PV production deposition processes. In-situ sensor development activities have resulted in improved control and indicate the potential for enhanced process status monitoring and control of all deposition processes. In spite of the short time since the program was initiated, substantial process improvements have been made, including significant improvement in CIGS uniformity, thickness control (e.g., 71% reduction in Cu variability), yield, and throughput.
Date: February 1, 2004
Creator: Simpson, L.
System: The UNT Digital Library
Avian Monitoring and Risk Assessment at the Tehachapi Pass Wind Resource Area; Period of Performance: October 2, 1996--May 27, 1998 (open access)

Avian Monitoring and Risk Assessment at the Tehachapi Pass Wind Resource Area; Period of Performance: October 2, 1996--May 27, 1998

Observations of dead raptors at the Altamont Pass Wind Resource Area triggered concerns on the parts of regulatory agencies, environmental/conservation groups, wildlife resource agencies, and wind and electric utility industries about possible impacts to birds from wind energy development. Bird fatality rates observed at most wind projects are not currently considered significant to individual bird species populations. Although many bird species have observed fatalities, raptors have received the most attention. The primary objective of this study was to estimate and compare bird utilization, fatality rates, and collision risk indices among factors such as bird taxonomic groups, turbine types, and turbine locations within the operating wind plant in the Tehachapi Pass WRA, in south-central California between October 1996 and May 1998.
Date: September 1, 2004
Creator: Anderson, R.; Neumann, N.; Tom, J.; Erickson, W. P.; Strickland, M. D.; Bourassa, M. et al.
System: The UNT Digital Library
Multi-Pulse DARHT Machine-Plasma Plume Problem (open access)

Multi-Pulse DARHT Machine-Plasma Plume Problem

The plasma current decay time constant is predicted to be short compared to the pulse length and so self-focusing is predicted for most of the beam pulse. Four- pulse beam envelopes for a high dose case require mitigation, those for a low dose case do not. Methods of mitigation are summarized. Hose instability growth in the plume length is predicted to be minimal.
Date: July 1, 2004
Creator: Lauer, E J
System: The UNT Digital Library
S816, S817, and S818 Airfoils: October 1991--July1992 (open access)

S816, S817, and S818 Airfoils: October 1991--July1992

A family of thick laminar-flow airfoils for 30 to 40-meter horizontal-axis wind turbines, the S816, S817, and S818, has been designed and analyzed theoretically. The primary objectives of restrained maximum lift, insensitive to roughness, and low profile drag have been achieved. The constraints on the pitching moments and airfoil thicknesses have been satisfied.
Date: December 1, 2004
Creator: Somers, D. M.
System: The UNT Digital Library
Potential Economic Impact of Constructing and Operating Solar Power Generation Facilities in Nevada (open access)

Potential Economic Impact of Constructing and Operating Solar Power Generation Facilities in Nevada

Nevada has a vast potential for electricity generation using solar power. An examination of the stock of renewable resources in Nevada proves that the state has the potential to be a leader in renewable-electric generation--one of the best in the world. This study provides estimates on the economic impact in terms of employment, personal income, and gross state product (GSP) of developing a portion of Nevada's solar energy generation resources.
Date: February 1, 2004
Creator: Schwer, R. K. & Riddel, M.
System: The UNT Digital Library
Power Technologies Data Book 2003 Edition (open access)

Power Technologies Data Book 2003 Edition

The 2003 edition of this report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts and comparisons, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, conversion factors, and selected congressional questions and answers.
Date: June 1, 2004
Creator: Aabakken, J.
System: The UNT Digital Library
NON-DESTRUCTIVE SOIL CARBON ANALYZER. (open access)

NON-DESTRUCTIVE SOIL CARBON ANALYZER.

This report describes the feasibility, calibration, and safety considerations of a non-destructive, in situ, quantitative, volumetric soil carbon analytical method based on inelastic neutron scattering (INS). The method can quantify values as low as 0.018 gC/cc, or about 1.2% carbon by weight with high precision under the instrument's configuration and operating conditions reported here. INS is safe and easy to use, residual soil activation declines to background values in under an hour, and no radiological requirements are needed for transporting the instrument. The labor required to obtain soil-carbon data is about 10-fold less than with other methods, and the instrument offers a nearly instantaneous rate of output of carbon-content values. Furthermore, it has the potential to quantify other elements, particularly nitrogen. New instrumentation was developed in response to a research solicitation from the U.S. Department of Energy (DOE LAB 00-09 Carbon Sequestration Research Program) supporting the Terrestrial Carbon Processes (TCP) program of the Office of Science, Biological and Environmental Research (BER). The solicitation called for developing and demonstrating novel techniques for quantitatively measuring changes in soil carbon. The report includes raw data and analyses of a set of proof-of-concept, double-blind studies to evaluate the INS approach in the first phase …
Date: February 1, 2004
Creator: WIELOPOLSKI,L. MITRA,S. HENDREY,G. ORION,I. ROGERS,H. TORBERT,A. PRIOR,S. RUNION,B.
System: The UNT Digital Library
California GAMA Program: A Contamination Vulnerability Assessment for the Bakersfield Area (open access)

California GAMA Program: A Contamination Vulnerability Assessment for the Bakersfield Area

In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MTBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey (USGS), the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2003, LLNL carried out this vulnerability study in the groundwater basin that underlies Bakersfield, in …
Date: November 1, 2004
Creator: Moran, J. E.; Hudson, G. B.; Eaton, G. F. & Leif, R.
System: The UNT Digital Library
Technical Basis Document for at-Power Significance Determination Process (SDP) Notebooks. (open access)

Technical Basis Document for at-Power Significance Determination Process (SDP) Notebooks.

To support the assessment of inspection findings as part of the risk-informed inspection in the United States Nuclear Regulatory Commission's (USNRC's) Reactor Oversight Process (ROP), risk inspection notebooks, also called significance determination process (SDP) notebooks, have been developed for each of the operating plants in the United States. These notebooks serve as a tool for assessing risk significance of inspection findings along with providing an engineering understanding of the significance. Plant-specific notebooks are developed to capture plant-specific features, characteristics, and analyses that influence the risk profile of the plant. At the same time, the notebooks follow a consistent set of assumptions and guidelines to assure consistent treatment of inspection findings across the plants. To achieve these objectives, notebooks are designed to provide specific information that are unique both in the manner in which the information is provided and in the way the screening risk assessment is carried out using the information provided. The unique features of the SDP notebooks, the approaches used to present the information for assessment of inspection findings, the assumptions used in consistent modeling across different plants with due credit to plant-specific features and analyses form the technical basis of the SDP notebooks. In this document, the …
Date: June 1, 2004
Creator: Azarm, M. A.; Smanta, P. K.; Martinez-Guridi, G. & Higgins, J.
System: The UNT Digital Library
Strategies for Energy-Efficient Remodeling: SEER 2003 Case Study Report; February 27, 2003 -- October 31, 2004 (open access)

Strategies for Energy-Efficient Remodeling: SEER 2003 Case Study Report; February 27, 2003 -- October 31, 2004

The goal of the Strategies for Energy Efficiency in Remodeling (SEER) project is to provide information, based on research and case studies, to remodelers and consumers about opportunities to increase home energy performance. Opportunities to include energy efficiency often arise while undertaking general remodeling work. This case study report examines the technologies, methods, and installation of specific energy efficiency strategies. The information presented here stems from a ''gut rehab'' of a house in rural New Jersey as part of the SEER project through the Building America Existing Buildings Program.
Date: November 1, 2004
Creator: Drumheller, S. C. & Wiehagen, J.
System: The UNT Digital Library
Development of Advanced Deposition Technology for Microcrystalline Si Based Solar Cells and Modules: Final Technical Report, 1 May 2002-31 July 2004 (open access)

Development of Advanced Deposition Technology for Microcrystalline Si Based Solar Cells and Modules: Final Technical Report, 1 May 2002-31 July 2004

The key objective of this subcontract was to take the first steps to extend the radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) manufacturing technology of Energy Photovoltaics, Inc. (EPV), to the promising field of a-Si/nc-Si solar cell fabrication by demonstrating ''proof-of-concept'' devices of good efficiencies that previously were believed to be unobtainable in single-chamber reactors owing to contamination problems. A complementary goal was to find a new high-rate deposition method that can conceivably be deployed in large PECVD-type reactors. We emphasize that our goal was not to produce 'champion' devices of near-record efficiencies, but rather, to achieve modestly high efficiencies using a far simpler (cheaper) system, via practical processing methods and materials. To directly attack issues in solar-cell fabrication at EPV, the nc-Si thin films were studied almost exclusively in the p-i-n device configuration (as absorbers or i-layers), not as stand-alone films. Highly efficient, p-i-n type, nc-Si-based solar cells are generally grown on expensive, laboratory superstrates, such as custom ZnO/glass of high texture (granular surface) and low absorption. Also standard was the use of a highly effective back-reflector ZnO/Ag, where the ZnO can be surface-textured for efficient diffuse reflection. The high-efficiency ''champion'' devices made by the PECVD methods were invariably prepared …
Date: December 1, 2004
Creator: Li, Y. M.
System: The UNT Digital Library