Innovative Design Approaches for Large Wind Turbine Blades (open access)

Innovative Design Approaches for Large Wind Turbine Blades

The primary goal of the WindPACT Blade System Design Study (BSDS) was investigation and evaluation of design and manufacturing issues for wind turbine blades in the one to ten megawatt size range. The initial project task was to assess the fundamental physical and manufacturing issues that govern and constrain large blades and entails three basic elements: (1) a parametric scaling study to assess blade structure using current technology, (2) an economic study of the cost to manufacture, transport, and install large blades, and (3) identification of promising innovative design approaches that show potential for overcoming fundamental physical and manufacturing constraints. This report discusses several innovative design approaches and their potential for blade cost reduction. During this effort we reviewed methods for optimizing the blade cross-section to improve structural and manufacturing characteristics. We also analyzed and compared a number of composite materials and evaluated their relative merits for use in large wind turbine blades in the range from 30 meters to 70 meters. The results have been summarized in dimensional and non-dimensional format to aid in interpretation. These results build upon earlier parametric and blade cost studies, which were used as a guide for the innovative design approaches explored here.
Date: March 1, 2003
Creator: ASHWILL, THOMAS D.
Object Type: Report
System: The UNT Digital Library
Electricity: The Road Toward Restructuring (open access)

Electricity: The Road Toward Restructuring

The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: March 14, 2003
Creator: Abel, Amy & Parker, Larry
Object Type: Report
System: The UNT Digital Library
International Law and the Preemptive Use of Force Against Iraq. March 2003 (open access)

International Law and the Preemptive Use of Force Against Iraq. March 2003

This report examines that issue as developed in customary international law and under the United Nations Charter.
Date: March 17, 2003
Creator: Ackerman, David M.
Object Type: Report
System: The UNT Digital Library
Public Aid to Faith-Based Organizations (Charitable Choice): Background and Selected Legal Issues (open access)

Public Aid to Faith-Based Organizations (Charitable Choice): Background and Selected Legal Issues

This report provides background on ten selected questions related to public aid for faith-based organization. Despite the ongoing controversy about charitable choice, not until the 107th Congress were there full hearings and extended debates on its constitutionality, efficacy, and public policy implications.
Date: March 28, 2003
Creator: Ackerman, David M.
Object Type: Report
System: The UNT Digital Library
War Powers Litigation Initiated by Members of Congress Since the Enactment of the War Powers Resolution (open access)

War Powers Litigation Initiated by Members of Congress Since the Enactment of the War Powers Resolution

None
Date: March 19, 2003
Creator: Ackerman, David M.
Object Type: Report
System: The UNT Digital Library
Extraction of macro-molecule images in cryo-EM micrographs (open access)

Extraction of macro-molecule images in cryo-EM micrographs

Advances in Electron Microscopy and single-particle reconstruction have led to results at increasingly high resolutions. This has opened up the possibility of complete automation of single particle reconstruction. Main bottleneck in automation of single particle reconstruction is manual selection of particles in the micrograph. This paper describes a simple but efficient approach for segmentation of particle projections in the micrographs obtained using cryo-electron microscope. Changing the shape of objects to facilitate segmentation from the cluster and reconstructing its actual shape after isolation is successfully attempted. Both low-level and high-level processing techniques are used and the whole process is made automatic. Over 90 percent success in automatic particle picking is achieved. Several areas for improvement and future research directions are discussed.
Date: March 20, 2003
Creator: Adiga, Umesha P.S.; Malladi, Ravi & Glaeser, Robert M.
Object Type: Report
System: The UNT Digital Library
Proteomics: Technology and Applications (open access)

Proteomics: Technology and Applications

This meeting took place at the Keystone, Colorado resort from March 25-30, 2003. It was attended by 206 participants, of which 35 were students; 39% of attendees submitted abstracts. The meeting had 30% returning attendees and 70% new attendees. The group of speakers was composed of internationally recruited junior and senior experts in their respective fields. The group included representatives from academia and the private sector, highlights the convergence of proteomics efforts in the two sectors. The completion of the genome sequences of a large number of prokaryotic and eukaryotic species has catalyzed new research approaches to study the structure, function and control of biological processes. They are characterized by the systematic and in many cases quantitative analysis of all the molecules of a particular type expressed by a cell or tissue. The systematic analysis of proteins has been terms ''proteomics''. In an initial phase, most of the proteomics efforts were focused on large-scale protein identification. More recently, the objectives and technologies of proteomics have been diversified and expanded. Current proteomics research attempts to systematically and, where applicable, quantitatively determine the many properties of proteins and their biological function, including: protein abundance, state of modification, specific activity, interaction with other …
Date: March 25, 2003
Creator: Aebersold, Ruedi
Object Type: Report
System: The UNT Digital Library
An infrastructure for passive network monitoring of application data streams (open access)

An infrastructure for passive network monitoring of application data streams

When diagnosing network problems, it is often desirable to have a view of traffic inside the network. In this paper we describe an infrastructure for passive monitoring that can be used to determine which segments of the network are the source of problems for an application data stream. The monitoring hosts are relatively low-cost, off-the-shelf PCs. A unique feature of the infrastructure is secure activation of monitoring hosts in the core of the network without direct network administrator intervention.
Date: March 1, 2003
Creator: Agarwal, Deb; Gonzalez, Jose Maria; Jin, Guojun & Tierney, Brian
Object Type: Article
System: The UNT Digital Library
Trade and the Americas (open access)

Trade and the Americas

None
Date: March 20, 2003
Creator: Ahearn, Raymond J.
Object Type: Report
System: The UNT Digital Library
U.S.-European Union Trade Relations: Issues and Policy Challenges (open access)

U.S.-European Union Trade Relations: Issues and Policy Challenges

None
Date: March 21, 2003
Creator: Ahearn, Raymond J.
Object Type: Report
System: The UNT Digital Library
Streamlined Energy-Savings Calculations for Heat-Island Reduction Strategies (open access)

Streamlined Energy-Savings Calculations for Heat-Island Reduction Strategies

We have developed summary tables (sorted by heating- and cooling-degree-days) to estimate the potential of Heat-Island Reduction (HIR) strategies (i.e., solar-reflective roofs, shade trees, reflective pavements, and urban vegetation) to reduce cooling-energy use in buildings. The tables provide estimates of savings for both direct effect (reducing heat gain through the building shell) and indirect effect (reducing the ambient air temperature). In this analysis, we considered three building types that offer the most savings potential : residences, offices, and retail stores. Each building type was characterized in detail by Pre-1980 (old) or 1980+ (new) construction vintage and with natural gas or electricity as heating fuel. We defined prototypical-building characteristics for each building type and simulated the effects of HIR strategies on building cooling and heating energy use and peak power demand using the DOE-2.1E model and weather data for about 240 locations in the U.S. A statistical analysis of previously completed simulations for five cities was used to estimate the indirect savings. Our simulations included the effect of (1) solar-reflective roofing material on building [direct effect], (2) placement of deciduous shade trees near south and west walls of building [direct effect], and (3) ambient cooling achieved by urban reforestation and reflective …
Date: March 15, 2003
Creator: Akbari, Hashem & Konopacki, Steven J.
Object Type: Report
System: The UNT Digital Library
Smart Screening System (S3) In Taconite Processing (open access)

Smart Screening System (S3) In Taconite Processing

Initial assessment of vibrating fine screens at a taconite processing plant in Mountain Iron Minnesota showed undesirable high noise and vibration levels. This has resulted in lower screening efficiency, higher energy and maintenance cost, and lower productivity and workers safety concerns. Current material separation technology uses heavy electric motors with an unbalance rotating mass to generate the shaking. These motors along with the screens and supporting structure shake other machines and structure in the vicinity of the screens. SmartScreens{trademark} technology, based on smart materials, uses miniaturized motors to generate shaking. This technology, based on Energy Flow Control{trademark} and Vibration Control by Confinement{trademark}, can efficiently and effectively direct the energy flow and confine it to the screens. The SmartScreens{trademark} technology addresses problems related to noise and vibration, screening efficiency, productivity, maintenance cost, and worker safety. Successful development of SmartScreens{trademark} technology will bring drastic change to the screening and physical separation industry. The conceptual designs for SmartScreens{trademark} resonators have been developed. These resonators will be utilized to amplify motion generated by smart motors. Resonator designs are down selected based on the final system requirement and vibration characteristics. The most promising resonator designs are incorporated in the full system model and are analyzed …
Date: March 1, 2003
Creator: Allaei, Daryoush; Mohammed, Asim Syed & Tarnowski, David
Object Type: Report
System: The UNT Digital Library
Kalispel Resident Fish Project: Annual Report, 2002. (open access)

Kalispel Resident Fish Project: Annual Report, 2002.

In 2002 the Kalispel Natural Resource Department (KNRD) continued monitoring enhancement projects (implemented from 1996 to 1998) for bull trout (Salvelinus confluentus), westslope cutthroat (Oncorhynchus clarki lewisi) and largemouth bass (Micropterus salmoides). Additional baseline fish population and habitat assessments were conducted, in 2002, in tributaries to the Pend Oreille River. Further habitat and fish population enhancement projects were also implemented in 2002.
Date: March 1, 2003
Creator: Andersen, Todd & Olson, Jason
Object Type: Report
System: The UNT Digital Library
LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES (open access)

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

This report represents a summary of the work carried out on this project which started October 1999 and ended March 2003. A list of the publications resulting from the work are contained in Appendix A. The most significant achievements are: (1) Dense nanocrystalline zirconia and ceria films were obtained at temperatures < 400 C. (2) Nanocrystalline films of both ceria and zirconia were characterized. (3) We showed that under anodic conditions 0.5 to 1 micron thick nanocrystalline films of Sc doped zirconia have sufficient electronic conductivity to prevent them from being useful as an electrolyte. (4) We have developed a process by which dense 0.5 to 5 micron thick dense films of either YSZ or ceria can be deposited on sintered porous substrates which serve as either the cathode or anode at temperatures as low as 400 C. (5) The program has provided the research to produce two PhD thesis for students, one is now working in the solid oxide fuel cell field. (6) The results of the research have resulted in 69 papers published, 3 papers submitted or being prepared for publication, 50 oral presentations and 3 patent disclosures.
Date: March 31, 2003
Creator: Anderson, Harlan U.; Dogan, Fatih & Petrovsky, Vladimir
Object Type: Report
System: The UNT Digital Library
Coming to Washington, D.C.? Sources of Information on Temporary Housing (open access)

Coming to Washington, D.C.? Sources of Information on Temporary Housing

This report will introduce a newcomer to the Washington, D.C., metropolitan area to sources of general interest, neighborhoods, housing, and public transportation. The intended audience is congressional staff needing short-term or summer housing, although many of the sources given may also be helpful for those needing more than a three- to six-month lease. Sources suggested are often accessible by their Internet addresses.
Date: March 20, 2003
Creator: Anderson, J. Michael
Object Type: Report
System: The UNT Digital Library
Enron: A Select Chronology of Congressional, Corporate, and Government Activities (open access)

Enron: A Select Chronology of Congressional, Corporate, and Government Activities

This report presents basic background information on the collapse of the Enron Corporation, identifying public policy issues in financial market oversight. This report briefly summarizes some federal laws carrying criminal penalties which may be implicated in the events surrounding the collapse of the Enron Corp. This report compares the auditing and accounting reform measures passed by the House (H.R. 3763) and reported by the Senate Committee on Banking, Housing, and Urban Affairs. This report compares the major provisions of three auditor and accounting reform proposals: H.R. 3763, S. 2673, and a rule proposed on June 20, 2002, by the SEC that would create a new auditor oversight board by using the SEC’s existing authority to regulate corporate accounting. The report focuses on Section 404(a) of the Employee Retirement Income Security Act (ERISA), the federal statute that regulates employer-sponsored pension plans. Section 404(a) is considered the “touchstone for understanding the scope and object of an ERISA fiduciary’s duties.”
Date: March 18, 2003
Creator: Anderson, J. Michael
Object Type: Report
System: The UNT Digital Library
Nuclear Data Measurements for 21st Century Reactor Physics Applications (open access)

Nuclear Data Measurements for 21st Century Reactor Physics Applications

The United States Department of Energy (DOE), Office of Nuclear Energy (NE) has embarked on a long-term program to significantly advance the science and technology of nuclear energy. This is in response to the overall national plan for accelerated development of domestic energy resources on several fronts, punctuated by recent dramatic events that have emphasized the need for the US to reduce its dependence on foreign petroleum supplies. Key aspects of the DOE-NE agenda are embodied in the Generation-IV (Gen-IV) advanced nuclear energy systems development program and in the Advanced Fuel Cycle (AFC) program. The planned efforts involve near-term and intermediate-term improvements in fuel utilization and recycling in current nuclear power reactor systems as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. The success of the overall NE effort will depend not only on sophisticated system development and engineering, but also on the advances in the supporting sciences and technologies. Of these, one of the most important is the improvement of the relevant fundamental nuclear science data bases, especially the evaluated neutron interaction cross section files that serve as the foundation of …
Date: March 1, 2003
Creator: Aryaeinejad, Rahmat; Cole, Jerald D.; Drigert, Mark W.; Jewell, James K.; McGrath, Christopher A.; Nigg, David W. et al.
Object Type: Report
System: The UNT Digital Library
Innovative Methods for Corn Stover Collecting, Handling, Storing and Transporting (open access)

Innovative Methods for Corn Stover Collecting, Handling, Storing and Transporting

Investigation of innovative methods for collecting, handling, storing, and transporting corn stover for potential use for production of cellulosic ethanol.
Date: March 1, 2003
Creator: Atchison, J. E. & Hettenhaus, J. R.
Object Type: Report
System: The UNT Digital Library
Catalytic Hydration of Alkenes and Alkynes (open access)

Catalytic Hydration of Alkenes and Alkynes

The fifteen years of DOE support have encompassed two different projects, electron-transfer reactions of metal carbonyl anions and water-soluble organometallic complexes. Each of these is related to homogeneous catalysis and will be described in separate sections. Electron Transfer--Twenty-one manuscripts resulted from our studies of electron-transfer reactions of metal carbonyl anions and acknowledge DOE support. Construction of an infrared stopped-flow system allowed us to measure rates of reactions for the extremely air-sensitive metal carbonyl anions. As for carbanions, both one-electron and two-electron processes occur for metal carbonyl anions. The most unexpected feature was examples of a very rapid two-electron process, followed by a much slower one-electron back transfer. The two-electron processes were accompanied by transfer of a ligand between two metals, M-X + M{prime}{sup -} {yields} M{sup -} + M{prime}-X with X groups of CO{sup 2}, H{sup +}, CH{sub 3}{sup +} and Br{sup +}. These transfers, which can be considered nucleophilic displacements, occurred when M{prime}{sup -} was more nucleophilic than M{sup -}. The 21 published manuscripts explore one- and two-electron processes for many such organometallic complexes. Water-Soluble Organometallic Complexes--The potential of water-soluble organometallic complexes in ''green chemistry'' intrigued us. Sixteen manuscripts acknowledging DOE support have appeared thus far in this field. …
Date: March 18, 2003
Creator: Atwood, Jim D.
Object Type: Report
System: The UNT Digital Library
Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays (open access)

Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays

With a sample of approximately 89 million B{bar B} pairs collected with the BABAR detector, they measure branching fractions, determine the degree of longitudinal polarization, and search for direct CP violation in the decays B{sup 0} {yields} {phi}K*{sup 0} and B{sup +} {yields} {phi}K*{sup +}. They perform a search for other charmless vector-vector B decays involving {rho} and K*(892) resonances and observe the decays B{sup +} {yields} {rho}{sup 0} K*{sup +} and B{sup +} {yields} {rho}{sup 0}{rho}{sup +}. The branching fractions are measured to be {Beta}({phi}K*{sup 0}) = (11.1{sub -1.2}{sup +1.3} {+-} 1.1) x 10{sup -6}, {Beta}({phi}K*{sup +}) = (12.1{sub -1.9}{sup +2.1} {+-} 1.5) x 10{sup -6}, {Beta}({rho}{sup 0} K*{sup +}) = (7.7{sub -2.0}{sup +2.1} {+-} 1.4) x 10{sup -6}, and {Beta}({rho}{sup 0}{rho}{sup +}) = (9.9{sub -2.5}{sup +2.6} {+-} 2.5) x 10{sup -6}. The longitudinal polarization fractions are measured to be {Lambda}{sub L}/{Lambda}({phi}K*{sup 0}) = 0.65 {+-} 0.07 {+-} 0.04 and {Lambda}{sub L}/{Lambda}({phi}K*{sup +}) = 0.46 {+-} 0.12 {+-} 0.05. They measure the charge asymmetries: {Alpha}{sub CP}({phi}K*{sup 0}) = +0.04 {+-} 0.12 {+-} 0.02 and {Alpha}{sub CP}({phi}K*{sup +}) = +0.16 {+-} 0.17 {+-} 0.04.
Date: March 11, 2003
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Gaillard, J.-M.; Hicheur, A.; Karyotakis, Y. et al.
Object Type: Article
System: The UNT Digital Library
HVL{_}CTH: A Simple Tool That Simulates The Hyper-Velocity Launch of a Flyer Plate (open access)

HVL{_}CTH: A Simple Tool That Simulates The Hyper-Velocity Launch of a Flyer Plate

Sandia National Laboratories has developed a unique method for a hyper-velocity launch (HVL), the three-stage gun. The three-stage gun is a modified two-stage light-gas gun, consisting of a piston used in the first stage, an impactor in the second stage, and a flyer plate in the third stage. The impactor is made up of different material layers that are increasing in shock impedance. The graded or pillowed layers allow the flyer to be launched at velocities up to 16 km/s without the formation of a single shock wave in the flyer plate and without it melting. Under certain experimental conditions the flyer velocity cannot be measured by standard means, X-rays and VISAR. Also, there is a need to know the flyer velocity prior to a launch in order to calibrate instruments and determine the appropriate shot configuration. The objective of HVL{_}CTH is to produce an accurate forecast of the flyer plate velocity under different launch conditions. CTH is a Eulerian shock physics computational analysis package developed at Sandia National Laboratories. Using CTH requires knowledge of its syntax and capabilities. HVL{_}CTH allows the user to easily interface with CTH, through the use of Fortran programs and batch files, in order to …
Date: March 1, 2003
Creator: BLACKBURN, DANIEL R.; VOGLER, TRACY J. & CHHABILDAS, LALIT C.
Object Type: Report
System: The UNT Digital Library
Low-Level Detection of a Bacillus Anthracis Simulant using Love-Wave Biosensors on 36 Degree YX LiTaO3 (open access)

Low-Level Detection of a Bacillus Anthracis Simulant using Love-Wave Biosensors on 36 Degree YX LiTaO3

Crucial to low-level detection of biowarfare agents in aqueous environments is the mass sensitivity optimization of Love-wave acoustic sensors. The present work is an experimental study of 36{sup o} YX cut LiTaO{sub 3} based Love-wave devices for detection of pathogenic spores in aqueous conditions. Given that the detection limit (DL) of Love-wave based sensors is a strong function of the overlying waveguide, two waveguide materials have been investigated, which are polyimide and polystyrene. To determine the mass sensitivity of Love-wave sensor, bovine serum albumin (BSA) protein was injected into the Love-wave test cell while recording magnitude and phase shift across each sensor. Polyimide had the lowest mass detection limit with an estimated value of 1-2 ng/cm{sup 2}, as compared to polystyrene where DL = 2.0 ng/cm{sup 2}. Suitable chemistries were used to orient antibodies on the Love-wave sensor using adsorbed protein G. The thickness of each biofilm was measured using ellipsometry from which the surface concentrations were calculated. The monoclonal antibody BD8 with a high degree of selectivity for anthrax spores was used to capture the non-pathogenic simulant B. thuringiensis B8 spores. Bacillus Subtilis spores were used as a negative control to determine whether significant non-specific binding would occur. Spore …
Date: March 1, 2003
Creator: BRANCH,DARREN W. & BROZIK,SUSAN M.
Object Type: Report
System: The UNT Digital Library
Comparing the risk profiles of renewable and natural gas electricity contracts: A summary of the California Department of Water Resources contracts (open access)

Comparing the risk profiles of renewable and natural gas electricity contracts: A summary of the California Department of Water Resources contracts

Electricity markets in the United States have witnessed unprecedented instability over the last few years, with substantial volatility in wholesale market prices, significant financial distress among major industry organizations, and unprecedented legal, regulatory and legislative activity. These events demonstrate the considerable risks that exist in the electricity industry. Recent industry instability also illustrates the need for thoughtful resource planning to balance the cost, reliability, and risk of the electricity supplied to end-use customers. In balancing different supply options, utilities, regulators, and other resource planners must consider the unique risk profiles of each generating source. This paper evaluates the relative risk profiles of renewable and natural gas generating plants. The risks that exist in the electricity industry depend in part on the technologies that are used to generate electricity. Natural gas has become the fuel of choice for new power plant additions in the United States. To some, this emphasis on a single fuel source signals the potential for increased risk. Renewable generation sources, on the other hand, are frequently cited as a potent source of socially beneficial risk reduction relative to natural gas-fired generation. Renewable generation is not risk free, however, and also imposes certain costs on the electricity sector. …
Date: March 12, 2003
Creator: Bachrach, Devra; Wiser, Ryan; Bolinger, Mark & Golove, William
Object Type: Report
System: The UNT Digital Library
Design and Performance of Capping Layers for EUV Multilayer Mirrors (open access)

Design and Performance of Capping Layers for EUV Multilayer Mirrors

The reflectance stability of multilayer coatings for extreme ultraviolet lithography (EUVL) in a commercial tool environment is of uttermost importance to ensure continuous exposures with minimum maintenance cost. We have made substantial progress in designing the protective capping layer coatings, understanding their performance and estimating their lifetimes based on accelerated electron beam and EUV exposure studies. Our current capping layer coatings have about 40 times longer lifetimes than Si-capped multilayer optics. Nevertheless, the lifetime of current Ru-capped multilayers is too short to satisfy commercial tool requirements and further improvements are essential.
Date: March 10, 2003
Creator: Bajt, S.; Chapman, H. N.; Nuygen, N.; Alameda, J.; Robinson, J. C.; Malinowski, M. et al.
Object Type: Article
System: The UNT Digital Library