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Test Bed Taxonomy for Crawler

Description: This report contains an annotated taxonomy of challenges that web crawler may encounter online.
Date: July 2004
Creator: Boyko, Andrew; Anderson, Martha & Jones, Gina
Partner: International Internet Preservation Consortium

Web Harvesting Survey

Description: This report contains a survey of the conditions found on web sites that influence the harvesting of content and the quality of an archival crawl.
Date: July 2004
Creator: Marill, Jennifer; Boyko, Andrew; Ashenfelder, Michael & Jones, Gina
Partner: International Internet Preservation Consortium

Iipc Web Archiving Metadata Set

Description: This report presents a set of metadata elements for web archiving.
Date: November 9, 2004
Creator: Masanès, Julien
Partner: International Internet Preservation Consortium

Characterizing Change in Web Archiving

Description: This report attempts to define the characteristics and dimensions of change in web content
Date: August 27, 2004
Creator: Boyko, Andrew
Partner: International Internet Preservation Consortium

Archiving Web Browser Plug-ins

Description: This report explores issues related to the archiving of Web Browser Plug-ins.
Date: January 9, 2004
Creator: Bang, Sverre
Partner: International Internet Preservation Consortium

[TDNA 2005 Budget Draft]

Description: A 2005 budget draft for the Texas Daily Newspaper Association. The document breaks down the expected income and expenses of the association for the 2005 year.
Date: November 19, 2004
Creator: Texas Daily Newspaper Association
Partner: UNT Libraries Special Collections

Texas Stonewall Democratic Caucus Custom Summary Report

Description: Custom summary report with a net income of $1,204.19 for the period ending on June 2004. Included is an Account QuickReport from June 1 through June 26, 2004 with a total of $1,025.00. Also, a general ledger of all the financial transactions as of June 30, 2004.
Date: June 2004
Partner: UNT Libraries Special Collections

Extrapolation of Extreme and Fatigue Loads Using Probabilistic Methods

Description: Probabilistic methods were used to determine the long-term extreme and fatigue loads of two different 1.5 MW wind turbine designs. Over the past decade, probabilistic methods for wind turbine design have acquired increasing levels of interest in both the research and industrial community. This interest has largely been driven by the desire to replace outdated empirical-based design models with more physically relevant models that can be accurately applied to the next generation of wind turbine designs. This study further extends previous works through further examination of moment-based probability methods, as well as the effects of using a joint distribution of mean wind speed and turbulence level, and the statistical uncertainty of moment-based methods, introducing refinements such as compensating for non-zero cyclic midpoints in fatigue calculations, application of a threshold technique and full integration of all probable operating conditions.
Date: November 1, 2004
Creator: Moriarty, P. J.; Holley, W. E. & Butterfield, S. P.
Partner: UNT Libraries Government Documents Department

Geometry and Structural Properties for the Controls Advanced Research Turbine (CART) from Model Tuning: August 25, 2003--November 30, 2003

Description: The Controls Advanced Research Turbine (CART) is a modified Westinghouse WWG-0600 machine rated at 600 kW. It is located at the National Wind Technology Center (NWTC) in Boulder, Colorado, and has been installed to test new control schemes for power and load regulation. In its original configuration, the WWG-0600 uses a synchronous generator, fluid coupling, and hydraulic collective pitch actuation. However, the CART is fitted with an induction generator, rigid coupling, and individual electromechanical pitch actuators. The rotor runs upwind of the tower and consists of two blades and a teetering hub. In order to design advanced control schemes for the CART, representative computational models are essential.
Date: September 1, 2004
Creator: Stol, K. A.
Partner: UNT Libraries Government Documents Department

Research in Hydrogen Passivation of Defects and Impurities in Silicon: Final Report, 2 May 2000-2 July 2003

Description: This subcontract report describes hydrogenating Si samples by different methods such as low-energy implantation, electron cyclotron resonance (ECR) plasma, and thermal diffusion. The samples were provided through NREL. The experimental work, carried out at Penn State, involved the study of hydrogen interaction with defects, trapping, migration, and formation of complexes. The principal vehicle for the latter study was ion implantation, and the intent to understand mechanisms of defect passivation and activation by hydrogen. NREL implemented a study of hydrogen passivation of impurities and defects in silicon solar cells. The work included theoretical and experimental components performed at different universities. The theoretical studies consisted of the calculation of the structure and parameters related to hydrogen diffusion and interactions of hydrogen with transition-metal impurities in silicon. Experimental studies involved measurements of hydrogen and hydrogen-impurity complexes, and diffusion properties of various species of hydrogen in Si. The experimental work at Penn State included introduction of hydrogen in a variety of PV Si by ECR plasma, low-energy ion implantation, and thermal diffusion. The specific tasks were the evaluation of hydrogen interaction with defects engineered by ion implantation; defect passivation, activation, and migration in hydrogenated Si under thermal anneal; and electrical activity of hydrogen-impurity complexes. Electrical characterization entailed I-V and C-V measurements, spreading resistance, and deep-level transient spectroscopy (DLTS).
Date: December 1, 2004
Creator: Ashok, S.
Partner: UNT Libraries Government Documents Department

Green Power Marketing in the United States: A Status Report; Seventh Edition

Description: Voluntary consumer decisions to purchase electricity supplied from renewable energy sources represent a powerful market support mechanism for renewable energy development. Beginning in the early 1990s, a small number of U.S. utilities began offering ''green power'' options to their customers. Since then, these products have become more prevalent both from utilities and in states that have introduced competition into their retail electricity markets. Today, more than 50% of all U.S. consumers have an option to purchase some type of green power product from a retail electricity provider. This report provides an overview of green power marketing activity in the United States. The first section provides an overview of green power markets, consumer response, and recent industry trends. Section 2 provides brief descriptions of the utility green pricing programs available nationally. Section 3 describes companies that actively market green power in competitive markets and those that market renew able energy certificates nationally or regionally. The last section provides information on a select number of large, nonresidential green power purchasers, including governmental agencies, universities, and businesses.
Date: September 1, 2004
Creator: Bird, L. & Swezey, B.
Partner: UNT Libraries Government Documents Department

Trends in Utility Green Pricing Programs (2003)

Description: Utilities first began offering consumers a choice of purchasing electricity generated from renewable energy sources in the early 1990s. Since then, the number of U.S. utilities offering green pricing programs has steadily grown. Today, more than 500 utilities in regulated electricity markets--or about 16% of all utilities nationally--offer their customers green power options. Because some of these utilities offer programs in conjunction with cooperative associations or other public power entities, the number of distinct programs is slightly more than 100. Through these programs, more than 33 million customers spanning 34 states have the ability to purchase renewable energy to meet some portion or all of their electricity needs, or make contributions to support the development of renewable energy resources. Typically, customers must pay a premium above standard electricity rates for this service. This report presents year-end 2003 data on utility green pricing programs, and examines trends in consumer response and program implementation over time. The data provided in this report can be used by utilities as benchmarks by which to gauge the success of their green power programs.
Date: September 1, 2004
Creator: Bird, L. & Cardinal, K.
Partner: UNT Libraries Government Documents Department

Turbine Research Program Cold Weather Turbine Project: Period of Performance May 27, 1999 -- March 31, 2004

Description: Northern Power Systems completed the Cold Weather Turbine (CWT) project, which was funded by the National Renewable Energy Laboratory (NREL), under subcontract XAT-9-29200-01. The project's primary goal is to develop a 100-kW wind turbine suited for deployment in remote villages in cold regions. The contract required testing and certification of the turbine to the International Electrotechnical Commission (IEC) 61400-1 international standard through Underwriters Laboratories (UL). The contract also required Northern Power Systems to study design considerations for operation in extreme cold (-80F at the South Pole, for example). The design was based on the successful proof of concept (POC) turbine (developed under NREL and NASA contracts), considered the prototype turbine that would be refined and manufactured to serve villages in cold regions around the world.
Date: August 1, 2004
Creator: Lynch, J.; Bywaters, G.; Costin, D.; Hoskins, S.; Mattila, P. & Stowell, J.
Partner: UNT Libraries Government Documents Department

Van Geet Off-Grid Home: An Integrated Approach to Energy Savings

Description: The Van Geet home near Denver, Colorado, exemplifies the effectiveness of coupling energy conservation measures with renewable energy utilization in a modern residence. The remote location, with no utility connections available, and the owner's interest in renewable energy motivated the ambitious design. This design attracted the interest of the Building America (BA) program and was studied as a research home. As a result, the BA program provided energy engineering throughout the design, construction, and performance evaluation phases. The American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) also recognized the success of this project by awarding it an ASHRAE Technology Award in 2001.
Date: August 1, 2004
Creator: Barley, C. D.; Torcellini, P. & Van Geet, O.
Partner: UNT Libraries Government Documents Department

Wind-Battery-Hydrogen Integration Study

Description: A study was performed to examine the possibility of using batteries and Hydrogen systems to add dispatchability to wind power. A second study examined the production of hydrogen by wind power for sale into a fuels market. Calendar year 2002 load information from the California ISO was combined with 2002 generated wind power from the Lake Benton wind farm in Minnesota. Control systems were developed and optimized, and grid operation for 2002 was simulated with batteries, electrolyzers, fuel cells or other elements. This report presents the results of the two studies.
Date: May 1, 2004
Creator: Fingersh, L. J.
Partner: UNT Libraries Government Documents Department

Development of an In-Line Minority-Carrier Lifetime Monitoring Tool for Process Control during Fabrication of Crystalline Silicon Solar Cells: Annual Subcontract Report, June 2003 (Revised)

Description: Under the PV Manufacturing R&D subcontract''Development of an In-Line, Minority-Carrier Lifetime Monitoring Tool for Process Control during Fabrication of Crystalline Silicon Solar Cells'', Sinton Consulting developed prototypes for several new instruments for use in the manufacture of silicon solar cells. These instruments are based on two families of R&D instruments that were previously available, an illumination vs. open-circuit-voltage technique and the quasi-steady state RF photoconductance technique for measuring minority-carrier lifetime. Compared to the previous instruments, the new prototypes are about 20 times faster per measurement, and have automated data analysis that does not require user intervention even when confronted by challenging cases. For example, un-passivated multi-crystalline wafers with large variations in lifetime and trapping behavior can be measured sequentially without error. Five instruments have been prototyped in this project to date, including a block tester for evaluating cast or HEM silicon blocks, a CZ ingot tester, an FZ boule tester for use with long-lifetime silicon, and an in-line sample head for measuring wafers. The CZ ingot tester and the FZ boule tester are already being used within industry and there is interest in the other prototypes. For each instrument, substantial R&D work was required in developing the device physics and analysis as well as for the hardware. This work has been documented in a series of application notes and conference publications, and will result in significant improvements for both the R&D and the industrial types of instruments.
Date: April 1, 2004
Creator: Sinton, R. A.
Partner: UNT Libraries Government Documents Department

Wind Turbine Field Testing of State-Space Control Designs: August 25, 2003--November 30, 2003

Description: This report investigates the application of advanced pitch control algorithms on a 600 kW variable-speed, variable-pitch wind turbine known as the Controls Advanced Research Turbine (CART). A design approach is outlined to test both time-invariant and periodic control methods for fatigue load reduction over all operating wind speeds. Practical implementation issues are identified and addressed. Test data and preliminary performance comparisons are presented to support the approach.
Date: September 1, 2004
Creator: Stol, K. A. & Fingersh, L. J.
Partner: UNT Libraries Government Documents Department

Wind Power Plant Behaviors: Analyses of Long-Term Wind Power Data

Description: The wind industry's growth is hampered by many market barriers, some of which stem from utilities' lack of experience with the technology. The effects of wind power fluctuations on power system operations and requirements of ancillary services for wind power have increasingly become concerns for many electric utilities and wind power developers. To remedy the situation, NREL has undertaken a project to record long-term, high-resolution wind power output data from large wind power plants in various regions.
Date: September 1, 2004
Creator: Wan, Y. H.
Partner: UNT Libraries Government Documents Department

Wind Tunnel Aeroacoustic Tests of Six Airfoils for Use on Small Wind Turbines; Period of Performance: August 23, 2002 through March 31, 2004

Description: The U.S. Department of Energy, working through the National Renewable Energy Laboratory, is engaged in a comprehensive research effort to improve our understanding of wind turbine aeroacoustics. Quiet wind turbines are an inducement to widespread deployment, so the goal of NREL's aeroacoustic research is to develop tools that the U.S. wind industry can use in developing and deploying highly efficient, quiet wind turbines at low wind speed sites. NREL's National Wind Technology Center is implementing a multifaceted approach that includes wind tunnel tests, field tests, and theoretical analyses in direct support of low wind speed turbine development by its industry partners. To that end, wind tunnel aerodynamic tests and aeroacoustic tests have been performed on six airfoils that are candidates for use on small wind turbines. Results are documented in this report.
Date: August 1, 2004
Creator: Oerlemans, S.
Partner: UNT Libraries Government Documents Department

WindPACT Rotor Design Study: Hybrid Tower Design; Period of Performance: 29 June 2000 -- 28 February 2004

Description: The cost of a wind turbine tower can represent as much as 20% of the cost of an entire megawatt-scale horizontal axis wind turbine (HAWT) and as much as 10% of the total cost of energy. The tower is a major cost component, and its design is important: Its structural properties are key to the response of the rotor; its height determines the wind regime that the rotor experiences; it allows access to the turbine nacelle and rotor; and it houses components of the electrical connection and the control and protection systems. Most large wind turbines installed in the United States use self-supporting steel tubular towers. The diameter of these tubes is limited by the size that can be transported by road (approximately 4.3 m). The base dimensions of a truss tower are not restrained by this limit, but trusses may require more maintenance. Guyed tube towers have been used, but they represent additional foundation costs and inconvenience. Addressing these limitations may lead to an alternative that avoids the problems. For this reason, the WindPACT Rotor Design Study was modified to include a study of a hybrid tower to determine the technical and economic feasibility of such a design.
Date: April 1, 2004
Creator: Malcolm, D. J.
Partner: UNT Libraries Government Documents Department

Innovative Approaches to Low Cost Module Manufacturing of String Ribbon Si PV Modules: First Annual Report, 27 September 2002--31 March 2003

Description: This report describes Evergreen Solar, Inc., String Ribbon Si PV technology resulting in an advanced generation of crystalline silicon PV module manufacturing technology applied to a virtually continuous, fully integrated manufacturing line. General objectives for this first year (or Phase I) are listed here, followed by the principal accomplishments for each of these objectives: (1) scale-up of a production-worthy method for doping feedstock; (2) development of a multiple-ribbon growth system (Project Gemini); (3) development of wrap-around contacts for making monolithic modules; (4) accelerated testing of small-size (25 W) monolithic modules; (5) development of an in-line production machine to form solar cell contacts using Evergreen's unique contact printing technology.
Date: May 1, 2004
Creator: Hanoka, J. I.
Partner: UNT Libraries Government Documents Department

International Energy Agency Building Energy Simulation Test and Diagnostic Method for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST): Volume 2: Cases E300-E545.

Description: This report documents an additional set of mechanical system test cases that are planned for inclusion in ANSI/ASHRAE STANDARD 140. The cases test a program's modeling capabilities on the working-fluid side of the coil, but in an hourly dynamic context over an expanded range of performance conditions. These cases help to scale the significance of disagreements that are less obvious in the steady-state cases. The report is Vol. 2 of HVAC BESTEST Volume 1. Volume 1 was limited to steady-state test cases that could be solved with analytical solutions. Volume 2 includes hourly dynamic effects, and other cases that cannot be solved analytically. NREL conducted this work in collaboration with the Tool Evaluation and Improvement Experts Group under the International Energy Agency (IEA) Solar Heating and Cooling Programme Task 22.
Date: December 1, 2004
Creator: J., Neymark & Judkoff, R.
Partner: UNT Libraries Government Documents Department