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Border Security: Security of New Passports and Visas Enhanced, but More Needs to Be Done to Prevent Their Fraudulent Use (open access)

Border Security: Security of New Passports and Visas Enhanced, but More Needs to Be Done to Prevent Their Fraudulent Use

A letter report issued by the Government Accountability Office with an abstract that begins "Travel documents are often used fraudulently in attempts to enter the United States. The integrity of U.S. passports and visas depends on the combination of well-designed security features and solid issuance and inspection processes. GAO was asked to examine (1) the features of U.S. passports and visas and how information on the features is shared; (2) the integrity of the issuance process for these documents; and (3) how these documents are inspected at U.S. ports of entry. We reviewed documents such as studies, alerts, and training materials. We met with officials from the Departments of State, Homeland Security, and Commerce's National Institute of Standards and Technology, and U.S. Government Printing Office, and with officials at seven passport offices, nine U.S. ports of entry, two U.S. consulates in Mexico, and two Border Crossing Card production facilities."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Aviation Security: Federal Coordination for Responding to In-flight Security Threats Has Matured, but Procedures Can Be Strengthened (open access)

Aviation Security: Federal Coordination for Responding to In-flight Security Threats Has Matured, but Procedures Can Be Strengthened

Correspondence issued by the Government Accountability Office with an abstract that begins "Five years after the terrorist attacks of September 11, 2001, concerns continue to be raised about the nation's system for protecting commercial aviation. Past disclosures of terrorists' plans for smuggling liquids onboard aircraft to construct a bomb in flight highlighted the continued need to examine this key aspect of homeland security. One layer of the aviation security system involves the ability of the federal government to respond to actual or potential security threats while a commercial aircraft is in flight. These security threats can include the following: (1) Passengers considered to be security risks to aviation are found to be onboard flights bound for or leaving the United States. (2) Situations develop while the aircraft is in flight--for example, a passenger becomes disruptive or acts suspiciously, a bomb threat is received, or an unidentified package is found onboard the aircraft. (3) A commercial aircraft transmits a signal designed to alert authorities that a hijacking is in process. Procedures for addressing these in-flight security threats involve a wide range of federal agencies and entities. The Department of Homeland Security (DHS) is responsible for taking much of the lead in …
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Information Technology: FBI Following a Number of Key Acquisition Practices on New Case Management System but Improvements Still Needed (open access)

Information Technology: FBI Following a Number of Key Acquisition Practices on New Case Management System but Improvements Still Needed

A letter report issued by the Government Accountability Office with an abstract that begins "The Sentinel program is intended to replace and expand on the Federal Bureau of Investigation's (FBI) failed Virtual Case File (VCF) project and thereby meet the bureau's pressing need for a modern, automated capability to support its field agents and intelligence analysts' investigative case management and information sharing requirements. Because of the FBI's experience with VCF and the importance of Sentinel to the bureau's mission operations, GAO was asked to conduct a series of reviews on the FBI's management of Sentinel. This review focuses on the FBI's (1) use of effective practices for acquiring Sentinel and (2) basis for reliably estimating Sentinel's schedule and costs. To address its objectives, GAO researched relevant best practices, reviewed FBI policies and procedures, program plans and other program documents, and interviewed appropriate program officials."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Veterans Affairs: Improved Planning Needed to Guide Development and Implementation of Education Benefits System (open access)

Veterans Affairs: Improved Planning Needed to Guide Development and Implementation of Education Benefits System

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Veterans Affairs (VA) administers programs that provide educational resources to veterans, service members, reservists, and eligible family members of veterans. Under an initiative that the Veterans Benefits Administration (VBA) began in 1999, called The Education Expert System (TEES), VA is moving its education benefits claims processing systems to new technology platforms and replacing the current systems with a new system that is to add more automated processes and eliminate most human intervention. GAO was requested to (1) report on the results of TEES development to date and identify the remaining work to complete the project, (2) identify VBA's plans for completing and implementing TEES, and (3) assess the feasibility of developing and deploying TEES before the completion of VBA's Finance and Accounting System. To accomplish these objectives, GAO analyzed relevant documentation, interviewed program and project officials, and observed processing systems at VA regional offices."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Defense Health Care: Under TRICARE, Children's Hospitals Paid More Than Other Hospitals After Accounting for Patient Complexity (open access)

Defense Health Care: Under TRICARE, Children's Hospitals Paid More Than Other Hospitals After Accounting for Patient Complexity

A letter report issued by the Government Accountability Office with an abstract that begins "Under the Department of Defense's (DOD) TRICARE health program, hospitals that treat primarily children--designated by DOD as children's hospitals--are paid differently from other types of civilian hospitals through a children's hospital differential payment. Representatives of children's hospitals state that payments for children's hospital services do not fully recognize the higher complexity of children's hospital patients. Acknowledging concerns over payments for children's hospital services, the National Defense Authorization Act for Fiscal Year 2006 directed GAO to study DOD's current system of payments to children's hospitals. This report examines (1) the effect of the differential on TRICARE's base payments to children's hospitals, (2) differences in diagnosis and complexity between TRICARE pediatric patients at children's hospitals and those at other hospitals, (3) the extent to which TRICARE payment differences across hospitals reflect differences in patient complexity, and (4) recent trends in TRICARE pediatric patients' use of children's hospital services. To do this, GAO analyzed pertinent TRICARE claims data for fiscal years 2003 through 2006 and interviewed relevant DOD officials and representatives of children's hospitals."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Federal Family Education Loan Program: Increased Department of Education Oversight of Lender and School Activities Needed to Help Ensure Program Compliance (open access)

Federal Family Education Loan Program: Increased Department of Education Oversight of Lender and School Activities Needed to Help Ensure Program Compliance

A letter report issued by the Government Accountability Office with an abstract that begins "Concerns have been raised about the Department of Education's (Education) role in overseeing the lenders and schools that participate in the largest of the federal government's student loan programs, the Federal Family Education Loan Program (FFELP). GAO was asked to analyze Education's use of its oversight, guidance, and enforcement authorities under FFELP. To do this, GAO reviewed departmental documents and federal laws, regulations, and cases and interviewed officials from Education and the student loan industry."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Military Personnel: Air National Guard Has Taken Steps to Improve the Reliability of Personnel Strength Data, but More Needs to Be Done (open access)

Military Personnel: Air National Guard Has Taken Steps to Improve the Reliability of Personnel Strength Data, but More Needs to Be Done

Correspondence issued by the Government Accountability Office with an abstract that begins "In September 2004, the Air National Guard (ANG) discovered inaccuracies in its personnel strength data for recruits with no prior service assigned to pay groups F (attending Initial Active Duty Training, or IADT) and P (awaiting IADT). Specifically, these data did not reflect an accurate accounting of the number of recruits in pay groups F and P. Those recruits attending IADT work full-time and are paid accordingly (pay group F), while recruits waiting to attend IADT receive pay on a part-time basis at the rate of four drills per month (pay group P). The pay for those attending IADT is much higher than for those waiting to attend IADT, so the effect of miscoding the pay groups on ANG's budget estimates can be considerable. In May 2007, we reported to Congress that although ANG has taken reasonable steps to correct the errors in its personnel strength data, some problems still exist with a key quality assurance tool (the Status Report Card process) and with the reliability of the alternate data being reported while the inaccuracies are addressed. The purpose of this correspondence is to inform Congress of the …
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Environmental Protection: EPA-State Enforcement Partnership Has Improved, but EPA's Oversight Needs Further Enhancement (open access)

Environmental Protection: EPA-State Enforcement Partnership Has Improved, but EPA's Oversight Needs Further Enhancement

A letter report issued by the Government Accountability Office with an abstract that begins "The Environmental Protection Agency (EPA) enforces the nation's environmental laws through its Office of Enforcement and Compliance Assurance (OECA). OECA sets overall enforcement policies and through its 10 regions oversees state agencies authorized to implement environmental programs consistent with federal requirements. GAO was asked to (1) identify trends in federal resources to regions and states for enforcement between 1997 and 2006, and determine regions' and states' views on the adequacy of these resources; (2) determine EPA's progress in improving priority setting and enforcement planning with states; and (3) examine EPA's efforts to improve oversight of states' enforcement programs and identify additional actions EPA could take to ensure more consistent state performance and oversight. GAO examined information from all 10 regions and 10 authorized states, among other things."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
TRICARE: Changes to Access Policies and Payment Rates for Services Provided by Civilian Obstetricians (open access)

TRICARE: Changes to Access Policies and Payment Rates for Services Provided by Civilian Obstetricians

Correspondence issued by the Government Accountability Office with an abstract that begins "About 111,000 women covered by the Department of Defense's (DOD) TRICARE program gave birth during 2006. During their pregnancies, about half of these women received obstetric care from physicians and other providers practicing at military hospitals and clinics called military treatment facilities (MTF), while half received their care from civilian physicians and other civilian providers. In recent years, the use of civilian obstetric care has increased among TRICARE beneficiaries. In 2004, 51 percent of TRICARE beneficiaries delivered their babies at civilian hospitals; by 2006, 54 percent delivered at civilian hospitals. However, through 2005, some TRICARE beneficiaries reported difficulties obtaining obstetric care from civilian physicians. At the same time, some civilian physicians contended that TRICARE payment rates for obstetric care were too low. TRICARE reimburses physicians for most obstetric care using two global payments, one for uncomplicated vaginal delivery and the other for uncomplicated cesarean delivery, each of which is a single amount that covers a defined set of related services. In the case of obstetrics, these global payments cover a woman's prenatal visits, the physician's assistance at delivery of the baby, and postnatal care after the delivery of …
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Defense Contract Management: DOD's Lack of Adherence to Key Contracting Principles on Iraq Oil Contract Put Government Interests at Risk (open access)

Defense Contract Management: DOD's Lack of Adherence to Key Contracting Principles on Iraq Oil Contract Put Government Interests at Risk

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Defense's (DOD) U.S. Army Corps of Engineers (Corps) awarded the $2.5 billion Restore Iraqi Oil (RIO I) contract to Kellogg Brown & Root in March 2003 in an effort to reestablish Iraq's oil infrastructure. The contract was also used to ensure adequate fuel supplies inside Iraq. RIO I was a cost-plus-award-fee type contract that provided for payment of the contractor's costs, a fixed fee determined at inception of the contract, and a potential award fee. The Defense Contract Audit Agency (DCAA) reviewed the 10 RIO I task orders and questioned $221 million in contractor costs. We were asked to determine (1) how DOD addressed DCAA's RIO I audit findings and what factors contributed to DOD's decision and (2) the extent to which DOD paid award fees for RIO I and followed the planned process for making that decision. To accomplish this, we reviewed DOD and DCAA documents related to RIO I and interviewed Corps, DCAA, and other officials."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Capitol Visitor Center: Update on Status of Project's Schedule and Cost as of July 31, 2007 (open access)

Capitol Visitor Center: Update on Status of Project's Schedule and Cost as of July 31, 2007

Testimony issued by the Government Accountability Office with an abstract that begins "Since the June 27, 2007, Capitol Visitor Center (CVC) hearing, the project's construction has progressed, and according to the latest schedule, Architect of the Capitol (AOC) is still projecting a June 27, 2008, completion date and a September 22, 2008 opening date. Work has advanced on the project's heating, ventilation, and air-conditioning (HVAC) system, interior wall stone and ceiling installation, and other interior and exterior construction work. However, some delays have occurred in activities on the project's critical path (i.e., the work on the fire alarm system) and on most of its near-critical paths, and further delays are possible. AOC was able to mitigate the delay in the project's critical path by reducing the time available for future fire alarm testing. This action may not produce the desired results, though, given the complexity of the requirements for fire alarm testing. Delays in near-critical activities such as the ceiling close-ins and the House and Senate expansion spaces have reduced the time reserved for contingencies along those near-critical paths, but have not yet affected the critical path. Furthermore, a number of risks to the project's schedule remain. These include potential …
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Homeland Security: Observations on DHS and FEMA Efforts to Prepare for and Respond to Major and Catastrophic Disasters and Address Related Recommendations and Legislation (open access)

Homeland Security: Observations on DHS and FEMA Efforts to Prepare for and Respond to Major and Catastrophic Disasters and Address Related Recommendations and Legislation

Testimony issued by the Government Accountability Office with an abstract that begins "The Federal Emergency Management Agency (FEMA) within the Department of Homeland Security (DHS) faces the simultaneous challenges of preparing for the season and implementing the reorganization and other provisions of the Post-Katrina Emergency Management Reform Act of 2006. The Act stipulated major changes to FEMA that were intended to enhance its preparedness for and response to catastrophic and major disasters. As GAO has reported, FEMA and DHS face continued challenges, including clearly defining leadership roles and responsibilities, developing necessary disaster response capabilities, and establishing accountability systems to provide effective services while protecting against waste, fraud, and abuse. This testimony (1) summarizes GAO's findings on these challenges and FEMA's and DHS's efforts to address them; and (2) discusses several disaster management issues for continued congressional attention."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Stabilizing Iraq: DOD Cannot Ensure That U.S.-Funded Equipment Has Reached Iraqi Security Forces (open access)

Stabilizing Iraq: DOD Cannot Ensure That U.S.-Funded Equipment Has Reached Iraqi Security Forces

A letter report issued by the Government Accountability Office with an abstract that begins "Since 2003, the United States has provided about $19.2 billion to develop Iraqi security forces. The Department of Defense (DOD) recently requested an additional $2 billion to continue this effort. Components of the Multinational Force-Iraq (MNF-I), including the Multinational Security Transition Command-Iraq (MNSTC-I), are responsible for implementing the U.S. program to train and equip Iraqi forces. This report (1) examines the property accountability procedures DOD and MNF-I applied to the U.S. train-and-equip program for Iraq and (2) assesses whether DOD and MNF-I can account for the U.S.-funded equipment issued to the Iraqi security forces. To accomplish these objectives, GAO reviewed MNSTC-I property books as of January 2007 and interviewed current and former officials from DOD and MNF-I."
Date: July 31, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Database and Analytical Tool Development for the Management of Data Derived from US DOE (NETL) Funded Fine Particulate (PM2.5) Research (open access)

Database and Analytical Tool Development for the Management of Data Derived from US DOE (NETL) Funded Fine Particulate (PM2.5) Research

Advanced Technology Systems, Inc. (ATS) was contracted by the U. S. Department of Energy's National Energy Technology Laboratory (DOE-NETL) to develop a state-of-the-art, scalable and robust web-accessible database application to manage the extensive data sets resulting from the DOE-NETL-sponsored ambient air monitoring programs in the upper Ohio River valley region. The data management system was designed to include a web-based user interface that will allow easy access to the data by the scientific community, policy- and decision-makers, and other interested stakeholders, while providing detailed information on sampling, analytical and quality control parameters. In addition, the system will provide graphical analytical tools for displaying, analyzing and interpreting the air quality data. The system will also provide multiple report generation capabilities and easy-to-understand visualization formats that can be utilized by the media and public outreach/educational institutions. The project was conducted in two phases. Phase One included the following tasks: (1) data inventory/benchmarking, including the establishment of an external stakeholder group; (2) development of a data management system; (3) population of the database; (4) development of a web-based data retrieval system, and (5) establishment of an internal quality assurance/quality control system on data management. Phase Two involved the development of a platform for …
Date: July 31, 2007
Creator: Khosah, Robinson
Object Type: Report
System: The UNT Digital Library
MODELLING THERMODYNAMICS OF ALLOYS FOR FUSION APPLICATION . Semi annual report for the Fusion Program (open access)

MODELLING THERMODYNAMICS OF ALLOYS FOR FUSION APPLICATION . Semi annual report for the Fusion Program

This research has two main objectives: (1) The development of computational tools to evaluate alloy properties, using the information contained in thermodynamic functions. We aim at improving the ability of classical potentials to account for complex alloy behavior; and (2) The application of these tools to predict properties of alloys under irradiation. Atomistic simulations of alloys at the empirical level face the challenge of correctly modeling basic thermodynamic properties. In the periods reported previously we develop a methodology to generalize many-body classic potentials to incorporate complex formation energy curves. Application to Fe-Cr allows us to predict the implications of the ab initio results of formation energy on the phase diagram of this alloy and to get a detailed insight into the processes leading to precipitation of {alpha}{prime} phase under irradiation. In particular in this period we report on the consequences of the negative heat of formation at low Cr composition on the short range order SRO existing in the {alpha} phase. We elaborate a simple description of SRO on a two phase alloy and compare the predictions with experiments. We provide a key to rationalize a diversity of experiments on SRO versus annealing time or irradiation dose.
Date: July 31, 2007
Creator: Caro, J A
Object Type: Report
System: The UNT Digital Library
Evaluation of 2004 Toyota Prius Hybrid Electic Drive System Interim Report - Revised (open access)

Evaluation of 2004 Toyota Prius Hybrid Electic Drive System Interim Report - Revised

The 2004 Toyota Prius is a hybrid automobile equipped with a gasoline engine and a battery-powered electric motor. Both of these motive power sources are capable of providing mechanical drive power for the vehicle. The engine can deliver a peak power output of 57 kilowatts (kW) at 5000 revolutions per minute (rpm) while the motor can deliver a peak power output of 50 kW at 1300 rpm. Together, this engine-motor combination has a specified peak power output of 82 kW at a vehicle speed of 85 kilometers per hour (km/h). In operation, the 2004 Prius exhibits superior fuel economy compared to conventionally powered automobiles. Laboratory tests were conducted to evaluate the electrical and mechanical performance of the 2004 Toyota Prius and its hybrid electric drive system. As a hybrid vehicle, the 2004 Prius uses both a gasoline-powered internal combustion engine and a battery-powered electric motor as motive power sources. Innovative algorithms for combining these two power sources results in improved fuel efficiency and reduced emissions compared to traditional automobiles. Initial objectives of the laboratory tests were to measure motor and generator back-electromotive force (emf) voltages and determine gearbox-related power losses over a specified range of shaft speeds and lubricating oil …
Date: July 31, 2007
Creator: Ayers, C. W.; Hsu, J. S.; Marlino, L. D.; Miller, C. W.; Ott, G. W., Jr.; Oland, C. B. et al.
Object Type: Report
System: The UNT Digital Library
Operation of a Public Geologic Core and Sample Repository in Houstion, Texas (open access)

Operation of a Public Geologic Core and Sample Repository in Houstion, Texas

The Bureau of Economic Geology's Houston Research Center (HRC) is well established as a premier regional research center for geologic research serving not only Houston, but geoscientists from around Texas, the U. S., and even the world. As reported in the FY05 and FY06 technical progress reports to the DOE, the HRC provides a state-of-the-art core viewing facility, two fully equipped conference rooms, and a comprehensive technical library, all available for public use. In addition, the HRC currently now houses over 725,000 boxes of rock material (as of January 2008), and has space to hold approximately 300,000 more boxes. Use of the facility has remained strong; the number of patrons averaged over 100 per month from June 1, 2006 to October 2007, and 90,000 boxes of core were donated to, and received by, the HRC during this time. Usage is a combination of individuals describing core, groups of geoscientists holding seminars and workshops, and various industry and government-funded groups holding short courses, workshops, and seminars. These numbers are in addition to the numerous daily requests from patrons desiring to have rock material shipped offsite to their own offices. The BEG/HRC secured several substantial donations of rock materials and cash totaling …
Date: July 31, 2007
Creator: Tinker, Scott & DeJarnett, Beverly
Object Type: Report
System: The UNT Digital Library
Process Design for the Biocatalysis of Value-Added Chemicals from Carbon Dioxide (open access)

Process Design for the Biocatalysis of Value-Added Chemicals from Carbon Dioxide

This report describes results toward developing a process to sequester CO{sub 2} centered on the enzymes PEP carboxylase and pyruvate carboxylase. The process involves the use of bacteria to convert CO{sub 2} and glucose as a co-substrate and generates succinic acid as a commodity chemical product. The study reports on strain development and process development. In the area of strain development, knockouts in genes which divert carbon from the enzymatic steps involved in CO{sub 2} consumption were completed, and were shown not to affect significantly the rate of CO{sub 2} sequestration and succinic acid generation. Furthermore, the pyc gene encoding for pyruvate carboxylase proved to be unstable when integrated onto the chromosome. In the area of process development, an optimal medium, pH and base counterion were obtained, leading to a sequestration rate as great as 800 mg/Lh. Detailed studies of gas phase composition demonstrated that CO{sub 2} composition has a significant affect on CO{sub 2} sequestration, while the presence of 'toxic' compounds in the gas, including NO{sub 2}, CO and SO{sub 2} did not have a detrimental effect on sequestration. Some results on prolonging the rate of sequestration indicate that enzyme activities decrease with time, suggesting methods to prolong enzyme …
Date: July 31, 2007
Creator: Eiteman, Mark
Object Type: Report
System: The UNT Digital Library
Flat-Field Calibration of CCD Detector for Long TraceProfilers (open access)

Flat-Field Calibration of CCD Detector for Long TraceProfilers

The next generation of synchrotrons and free electron lasersrequires x-ray optical systems with extremely high-performance,generally, of diffraction limited quality. Fabrication and use of suchoptics requires highly accurate metrology. In the present paper, wediscuss a way to improve the performance of the Long Trace Profiler(LTP), a slope measuring instrument widely used at synchrotron facilitiesto characterize x-ray optics at high-spatial-wavelengths fromapproximately 2 mm to 1 m. One of the major sources of LTP systematicerror is the detector. For optimal functionality, the detector has topossess the smallest possible pixel size/spacing, a fast method ofshuttering, and minimal non-uniformity of pixel-to-pixel photoresponse.While the first two requirements are determined by choice of detector,the non-uniformity of photoresponse of typical detectors such as CCDcameras is around 2-3 percent. We describe a flat-field calibration setupspecially developed for calibration of CCD camera photo-response and darkcurrent with an accuracy of better than 0.5 percent. Such accuracy isadequate for use of a camera as a detector for an LTP with performance of~;0.1 microradian (rms). We also present the design details of thecalibration system and results of calibration of a DALSA CCD camera usedfor upgrading our LTP-II instrument at the ALS Optical MetrologyLaboratory.
Date: July 31, 2007
Creator: Kirschman, Jonathan L.; Domning, Edward E.; Franck, Keith D.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R. et al.
Object Type: Article
System: The UNT Digital Library
PHASE 1 Technical Letter Report – TS-00358: Portable Acoustic Contraband Detector (open access)

PHASE 1 Technical Letter Report – TS-00358: Portable Acoustic Contraband Detector

This TLR provides the results of all PNNL managed activities on this project, and contains a description of the data acquisition configuration and testing protocols, results and conclusions from this work. This TLR is part of the final deliverables package submitted to the client during the Phase 1 Go/No-Go meeting in Richland, Washington, on July 31, 2007.
Date: July 31, 2007
Creator: Diaz, Aaron A.
Object Type: Report
System: The UNT Digital Library
Low Speed Technology for Small Turbine Development Reaction Injection Molded 7.5 Meter Wind Turbine Blade (open access)

Low Speed Technology for Small Turbine Development Reaction Injection Molded 7.5 Meter Wind Turbine Blade

An optimized small turbine blade (7.5m radius) was designed and a partial section molded with the RIM (reaction-injection molded polymer) process for mass production. The intended market is for generic three-bladed wind turbines, 100 kilowatts or less, for grid-assist end users with rural and semi-rural sites, such as the farm/ranch market, having low to moderate IEC Class 3-4 wind regimes. This blade will have substantial performance improvements over, and be cheaper than, present-day 7.5m blades. This is made possible by the injection-molding process, which yields high repeatability, accurate geometry and weights, and low cost in production quantities. No wind turbine blade in the 7.5m or greater size has used this process. The blade design chosen uses a RIM skin bonded to a braided infused carbon fiber/epoxy spar. This approach is attractive to present users of wind turbine blades in the 5-10m sizes. These include rebladeing California wind farms, refurbishing used turbines for the Midwest farm market, and other manufacturers introducing new turbines in this size range.
Date: July 31, 2007
Creator: Wright, David M. & Bennett, Keith
Object Type: Report
System: The UNT Digital Library
Proposal for a Universal Test Mirror for Characterization of SlopeMeasuring Instruments (open access)

Proposal for a Universal Test Mirror for Characterization of SlopeMeasuring Instruments

The development of third generation light sources like theAdvanced Light Source (ALS) or BESSY II brought to a focus the need forhigh performance synchrotron optics with unprecedented tolerances forslope error and micro roughness. Proposed beam lines at Free ElectronLasers (FEL) require optical elements up to a length of one meter,characterized by a residual slope error in the range of 0.1murad (rms),and rms values of 0.1 nm for micro roughness. These optical elements mustbe inspected by highly accurate measuring instruments, providing ameasurement uncertainty lower than the specified accuracy of the surfaceunder test. It is essential that metrology devices in use at synchrotronlaboratories be precisely characterized and calibrated to achieve thistarget. In this paper we discuss a proposal for a Universal Test Mirror(UTM) as a realization of a high performance calibration instrument. Theinstrument would provide an ideal calibration surface to replicate aredundant surface under test of redundant figure. The application of asophisticated calibration instrument will allow the elimination of themajority of the systematic error from the error budget of an individualmeasurement of a particular optical element. We present the limitationsof existing methods, initial UTM design considerations, possiblecalibration algorithms, and an estimation of the expectedaccuracy.
Date: July 31, 2007
Creator: Yashchuk, Valeriy V.; McKinney, Wayne R.; Warwick, Tony; Noll,Tino; Siewert, Frank; Zeschke, Thomas et al.
Object Type: Article
System: The UNT Digital Library
Low-temperature charge transport in Ga-acceptor nanowires implanted by focused-ion beams (open access)

Low-temperature charge transport in Ga-acceptor nanowires implanted by focused-ion beams

Ga-acceptor nanowires were embedded in crystalline Si using focused-ion beams. The dc current-voltage characteristics of these wires after annealing are highly nonlinear at low temperatures, and a threshold voltage of less than 50 mV is observed independent of Ga+ dosage and implant beam overlap. These features suggest a Coulomb blockade transport mechanism presumably caused by a network of Ga precipitates in the substrate. This granular scenario is further supported by measurements of gated nanowires. Nanowires with metallic conductance at low temperatures could be achieved by reducing the current density of the focused-ion beams.
Date: July 31, 2007
Creator: Schenkel, Thomas; Robinson, S.J.; Perkins, C.L.; Tucker, J.R.; Schenkel, T.; Wang, X.W. et al.
Object Type: Article
System: The UNT Digital Library
Neutron Beams from Deuteron Breakup at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (open access)

Neutron Beams from Deuteron Breakup at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory

Accelerator-based neutron sources offer many advantages, in particular tunability of the neutron beam in energy and width to match the needs of the application. Using a recently constructed neutron beam line at the 88-Inch Cyclotron at LBNL, tunable high-intensity sources of quasi-monoenergetic and broad spectrum neutrons from deuteron breakup are under development for a variety of applications.
Date: July 31, 2007
Creator: McMahan, M. A.; Ahle, L.; Bleuel, D. L.; Bernstein, L.; Braquest, B. R.; Cerny, J. et al.
Object Type: Article
System: The UNT Digital Library