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Trying Terrorists as War Criminals (open access)

Trying Terrorists as War Criminals

None
Date: October 29, 2001
Creator: Elsea, Jennifer K.
Object Type: Report
System: The UNT Digital Library
Cuba: U.S. Restrictions on Travel and Legislative Initiatives in the 107th Congress (open access)

Cuba: U.S. Restrictions on Travel and Legislative Initiatives in the 107th Congress

Since the United States imposed a comprehensive trade embargo against Cuba in the early 1960s, there have been numerous policy changes to restrictions on travel to Cuba. The embargo regulations do not ban travel itself, but place restrictions on any financial transactions related to travel to Cuba, which effectively result in a travel ban. This report reflects legislative or other major developments , including a listing and discussion of legislative initiatives in the 107th Congress.
Date: October 29, 2001
Creator: Sullivan, Mark P.
Object Type: Report
System: The UNT Digital Library
AIDS in Africa (open access)

AIDS in Africa

Sub-Saharan Africa has been far more severely affected by AIDS than any other part of the world. The United Nations reports that 25.3 million adults and children are infected with the HIV virus in the region, which has about 10% of the world's population but more than 70% of the worldwide total of infected people. This report discusses this issue in detail, including the cause of the African AIDS epidemic, the social and economic consequences, response and treatment, and U.S. policy.
Date: October 29, 2001
Creator: Copson, Raymond W.
Object Type: Report
System: The UNT Digital Library
[Funeral Program for Erastus James Clack, October 29, 2001] (open access)

[Funeral Program for Erastus James Clack, October 29, 2001]

Funeral program for Mr. Erastus James (E.J.) Clack, born September 28, 1921 and died October 23, 2001. The funeral was held October 29, 2001 at Jacob's Chapel United Methodist Church, officiated by Rev. Howard Mims. The funeral arrangements were made through Lewis Funeral Home and he was buried in Southern Memorial Park in San Antonio, Texas.
Date: October 29, 2001
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Structural and electronic properties of carbon nanotube tapers (open access)

Structural and electronic properties of carbon nanotube tapers

Article on structural and electronic properties of carbon nanotube tapers, a set of nanostructures comprised of straight tubular sections with decreasing diameters, joined to each other via conical funnels and terminated with a hemispherical cap.
Date: October 29, 2001
Creator: Meunier, Vincent; Buongiorno Nardelli, Marco; Roland, Christopher & Bernholc, Jerry
Object Type: Article
System: The UNT Digital Library
Electronic Commerce: Small Business Participation in Selected On-line Procurement Programs (open access)

Electronic Commerce: Small Business Participation in Selected On-line Procurement Programs

A letter report issued by the General Accounting Office with an abstract that begins "The federal government has been pursuing electronic initiatives to strengthen its buying processes, reduce costs, and create a competitive "virtual" marketplace. Small businesses, however, may have difficulty participating in federal on-line procurement programs. Furthermore, the government's business outreach and education programs related to electronic commerce may not be adequately coordinated. For the three federal on-line procurement programs GAO reviewed, the dollar share of awards to small businesses exceeded the overall small business share of total federal contract dollars awarded in fiscal years 2000 and 1999. Although small businesses successfully participated in these three programs, they still face obstacles in conducting electronic procurements with the government. The federal government is taking steps to address some of these obstacles, such as implementing a single point of entry on the Internet for vendors to access information on available government business opportunities greater than $25,000. Each of the four business assistance programs GAO examined had taken steps to educate its clients on electronic commerce as part of its operations. However, GAO could not fully determine the extent of these activities because they are conducted by hundreds of local and regional …
Date: October 29, 2001
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Extending the Constant Power Speed Range of the Brushless DC Motor through Dual Mode Inverter Control -- Part I: Theory and Simulation (open access)

Extending the Constant Power Speed Range of the Brushless DC Motor through Dual Mode Inverter Control -- Part I: Theory and Simulation

An inverter topology and control scheme has been developed that can drive low-inductance, surface-mounted permanent magnet motors over the wide constant power speed range required in electric vehicle applications. This new controller is called the dual-mode inverter control (DMIC) [1]. The DMIC can drive either the Permanent Magnet Synchronous Machine (PMSM) with sinusoidal back emf, or the brushless dc machine (BDCM) with trapezoidal emf in the motoring and regenerative braking modes. In this paper we concentrate on the BDCM under high-speed motoring conditions. Simulation results show that if all motor and inverter loss mechanisms are neglected, the constant power speed range of the DMIC is infinite. The simulation results are supported by closed form expressions for peak and rms motor current and average power derived from analytical solution to the differential equations governing the DMIC/BDCM drive for the lossless case. The analytical solution shows that the range of motor inductance that can be accommodated by the DMIC is more than an order of magnitude such that the DMIC is compatible with both low- and high-inductance BDCMs. Finally, method is given for integrating the classical hysteresis band current control, used for motor control below base speed, with the phase advance of …
Date: October 29, 2001
Creator: Lawler, J.S.
Object Type: Article
System: The UNT Digital Library
Lessons Learned in Testing of Safeguards Equipment. (open access)

Lessons Learned in Testing of Safeguards Equipment.

The International Atomic Energy Agency's (IAEA) Department of Safeguards uses complex instrumentation for the application of safeguards at nuclear facilities around the world. Often, this equipment is developed through cooperation with member state support programs because the Agency's requirements are unique and are not met by commercially available equipment. Before approving an instrument or system for routine inspection use, the IAEA subjects it to a series of tests designed to evaluate its reliability. In 2000, the IAEA began to observe operational failures in digital surveillance systems. In response to the observed failures, the IAEA worked with the equipment designer and manufacturer to determine the cause of failure. An action plan was developed to correct the performance issues and further test the systems to make sure that additional operational issues would not surface later. This paper addresses the steps taken to address operation issues related to digital image surveillance systems and the lessons learned during this process.
Date: October 29, 2001
Creator: Pepper, S.; Farnitano, M.; Carelli, J.; Hazeltine, J. & BAILEY,D. Bailey, D.
Object Type: Article
System: The UNT Digital Library
Monitoring and mitigation of sustained, localized pitting corrosion. (open access)

Monitoring and mitigation of sustained, localized pitting corrosion.

None
Date: October 29, 2001
Creator: Lin, Y. P.; St.Martin, E. J. & Frank, J. R.
Object Type: Article
System: The UNT Digital Library
High Temperature Surface Measurements Using Lifetime Imaging of Thermographic Phosphors: Bonding Tests (open access)

High Temperature Surface Measurements Using Lifetime Imaging of Thermographic Phosphors: Bonding Tests

Temperature-sensitive paint (TSP) comprised of thermally sensitive phosphor can provide a viable means for noncontact thermometry in wind tunnel and other aeropropulsion applications. Described here are recent results aimed at developing a phosphor and binder system that will cover a wide temperature range, ambient to 1000 C. The phosphor/binder mixture is to be sprayed directly on the surface with an airbrush. Whereas many surfaces are candidates for various uses, the present effort concerned silicon carbide, silicon nitride and silica substrates. Initial tests show that a phosphor mixture with two water-soluble materials, designated LK and HPC and manufactured by ZYP Inc., adhered well to these substrates. This same material was earlier shown to function well on a high strength nickel alloy.
Date: October 29, 2001
Creator: Allison, S. W.
Object Type: Article
System: The UNT Digital Library
Limitations of the Conventional Phase Advance Method for Constant Power Operation of the Brushless DC Motor (open access)

Limitations of the Conventional Phase Advance Method for Constant Power Operation of the Brushless DC Motor

The brushless dc motor (BDCM) has high-power density and efficiency relative to other motor types. These properties make the BDCM well suited for applications in electric vehicles provided a method can be developed for driving the motor over the 4 to 6:1 constant power speed range (CPSR) required by such applications. The present state of the art for constant power operation of the BDCM is conventional phase advance (CPA) [1]. In this paper, we identify key limitations of CPA. It is shown that the CPA has effective control over the developed power but that the current magnitude is relatively insensitive to power output and is inversely proportional to motor inductance. If the motor inductance is low, then the rms current at rated power and high speed may be several times larger than the current rating. The inductance required to maintain rms current within rating is derived analytically and is found to be large relative to that of BDCM designs using high-strength rare earth magnets. Th us, the CPA requires a BDCM with a large equivalent inductance.
Date: October 29, 2001
Creator: Lawler, J.S.
Object Type: Article
System: The UNT Digital Library
Modular PM Motor Drives for Automotive Traction Applications (open access)

Modular PM Motor Drives for Automotive Traction Applications

This paper presents modular permanent magnet (PM) motor drives for automotive traction applications. A partially modularized drive system consisting of a single PM motor and multiple inverters is described. The motor has multiple three-phase stator winding sets and each winding set is driven with a separate three-phase inverter module. A truly modularized inverter and motor configuration based on an axial-gap PM motor is then introduced, in which identical PM motor modules are mounted on a common shaft and each motor module is powered by a separate inverter module. The advantages of the modular approach for both inverter and motor include: (1) power rating scalability--one design meets different power requirements by simply stacking an adequate number of modules, thus avoiding redesigning and reducing the development cost, (2) increased fault tolerance, and (3) easy repairing. A prototype was constructed by using two inverters and an axial-gap PM motor with two sets of three-phase stat or windings, and it is used to assist the diesel engine in a hybrid electric vehicle converted from a Chevrolet Suburban. The effect of different pulse-width-modulation strategies for both motoring and regenerative modes on current control is analyzed. Torque and regenerative control algorithms are implemented with a digital …
Date: October 29, 2001
Creator: Su, G.J.
Object Type: Article
System: The UNT Digital Library
High Temperature Ceramic Fuel Cell Measurement and Diagnostics for Application to Solid Oxide Fuel Cell Systems (open access)

High Temperature Ceramic Fuel Cell Measurement and Diagnostics for Application to Solid Oxide Fuel Cell Systems

This paper is the result of an extensive literature review and technology evaluation, performed to determine the status of sensors and measurement technologies.
Date: October 29, 2001
Creator: Koehler, Theresa M; Jarrell, Donald B & Bond, Leonard J
Object Type: Report
System: The UNT Digital Library
An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock (open access)

An Improved Probabilistic Fracture Mechanics Model for Pressurized Thermal Shock

This paper provides an overview of an improved probabilistic fracture mechanics (PFM) model used for calculating the conditional probabilities of fracture and failure of a reactor pressure vessel (RPV) subjected to pressurized-thermal-shock (PTS) transients. The updated PFM model incorporates several new features: expanded databases for the fracture toughness properties of RPV steels; statistical representations of the fracture toughness databases developed through application of rigorous mathematical procedures; and capability of generating probability distributions for RPV fracture and failure. The updated PFM model was implemented into the FAVOR fracture mechanics program, developed at Oak Ridge National Laboratory as an applications tool for RPV integrity assessment; an example application of that implementation is discussed herein. Applications of the new PFM model are providing essential input to a probabilistic risk assessment (PRA) process that will establish an improved technical basis for re-assessment of current PTS regulations by the US Nuclear Regulatory Commission (NRC). The methodology described herein should be considered preliminary and subject to revision in the PTS re-evaluation process.
Date: October 29, 2001
Creator: Dickson, T. L.
Object Type: Article
System: The UNT Digital Library
Extending the Constant Power Speed Range of the Brushless DC Motor through Dual Mode Inverter Control -- Part II: Laboratory Proof-of-Principle (open access)

Extending the Constant Power Speed Range of the Brushless DC Motor through Dual Mode Inverter Control -- Part II: Laboratory Proof-of-Principle

Previous theoretical work has shown that when all loss mechanisms are neglected the constant power speed range (CPSR) of a brushless dc motor (BDCM) is infinite when the motor is driven by the dual-mode inverter control (DMIC) [1,2]. In a physical drive, losses, particularly speed-sensitive losses, will limit the CPSR to a finite value. In this paper we report the results of laboratory testing of a low-inductance, 7.5-hp BDCM driven by the DMIC. The speed rating of the test motor rotor limited the upper speed of the testing, and the results show that the CPSR of the test machine is greater than 6:1 when driven by the DMIC. Current wave shape, peak, and rms values remained controlled and within rating over the entire speed range. The laboratory measurements allowed the speed-sensitive losses to be quantified and incorporated into computer simulation models, which then accurately reproduce the results of lab testing. The simulator shows that the limiting CPSR of the test motor is 8:1. These results confirm that the DMIC is capable of driving low-inductance BDCMs over the wide CPSR that would be required in electric vehicle applications.
Date: October 29, 2001
Creator: Lawler, J.S.
Object Type: Article
System: The UNT Digital Library
Multilevel DC Link Inverter for Brushless Permanent Magnet Motors with Very Low Inductance (open access)

Multilevel DC Link Inverter for Brushless Permanent Magnet Motors with Very Low Inductance

Due to their long effective air gaps, permanent magnet motors tend to have low inductance. The use of ironless stator structure in present high power PM motors (several tens of kWs) reduces the inductance even further (< 100 {micro}H). This low inductance imposes stringent current regulation demands for the inverter to obtain acceptable current ripple. An analysis of the current ripple for these low inductance brushless PM motors shows that a standard inverter with the most commonly used IGBT switching devices cannot meet the current regulation demands and will produce unacceptable current ripples due to the IGBT's limited switching frequency. This paper introduces a new multilevel dc link inverter, which can dramatically reduce the current ripple for brushless PM motor drives. The operating principle and design guidelines are included.
Date: October 29, 2001
Creator: Su, G. J.
Object Type: Article
System: The UNT Digital Library
Development of an improved 2-cm centrifugal contactor for cesium removal from high-level waste. (open access)

Development of an improved 2-cm centrifugal contactor for cesium removal from high-level waste.

None
Date: October 29, 2001
Creator: Leonard, R. A.; Aase, S. B.; Arafat, H. A.; Conner, C.; Falkenberg, J. R. & Vandegrift, G. F.
Object Type: Report
System: The UNT Digital Library
Complex interfacial flows. Final report for period August 1, 1997 - July 31, 2001 (open access)

Complex interfacial flows. Final report for period August 1, 1997 - July 31, 2001

The objective of this grant was to study complex interfacial flows. Here we report on several problems considered. In particular we have investigated the motion of a liquid along a second liquid interface, we have investigated a canonical problem associated with the rupture of a viscous interface, we have investigated the dynamics of a gas bubble or drop in an inclined parallel walled channel under gravity with and without the presence of surfactants, we have studied the dynamics of a dry spot in a thin liquid film and we have developed a numerical code to study the dynamics of a liquid interface in a parallel walled channel. In addition, two students have completed their Ph.D. thesis during this grant period.
Date: October 29, 2001
Creator: Miksis, Michael J.
Object Type: Report
System: The UNT Digital Library
Effects of Silicon Carbide (SiC) Power Devices on HEV PWM Inverter Losses (open access)

Effects of Silicon Carbide (SiC) Power Devices on HEV PWM Inverter Losses

None
Date: October 29, 2001
Creator: Ospineci, B.
Object Type: Article
System: The UNT Digital Library
Investigation of Byproduct Application to Jet Fuel (open access)

Investigation of Byproduct Application to Jet Fuel

Subcontract report in which J.E. Sinor Consultants Inc. reported on a brief study of jet fuel characteristics and markets to determine whether any applications for an alkyl benzene product exist.
Date: October 29, 2001
Creator: J.E. Sinor Consultants, Inc.
Object Type: Report
System: The UNT Digital Library
Igneous Consequence Modeling for the TSPA-SR (open access)

Igneous Consequence Modeling for the TSPA-SR

The purpose of this technical report is to develop credible, defendable, substantiated models for the consequences of igneous activity for the TSPA-SR Model. The effort will build on the TSPA-VA and improve the quality of scenarios and depth of the technical basis underlying disruptive events modeling. Computational models for both volcanic eruptive releases (this is an event that results in ash containing waste being ejected from Yucca Mountain) and igneous intrusion groundwater releases (this is an event that reaches the repository level, impacts the waste packages, and produces releases from waste packages damaged by igneous activity) will be included directly in the TSPA calculations as part of the TSPA-SR Model. This Analysis Model Report (AMR) is limited to development of the conceptual models for these two scenarios. The mathematical implementation of these conceptual models will be done within the TSPA-SR Model. Thus, this AMR will not include any model results or sensitivity analyses. Calculation of any doses resulting from igneous releases will also be done within the TSPA-SR model, as will the probabilistic weighting of these doses. Calculation and analysis of the TSPA-SR Model results for igneous disruption are, therefore, outside the scope of this activity. The reason for not …
Date: October 29, 2001
Creator: McCord, John
Object Type: Report
System: The UNT Digital Library
Building America House Performance Analysis Procedures (open access)

Building America House Performance Analysis Procedures

As the Building America Program has grown to include a large and diverse cross section of the home building industry, accurate and consistent analysis techniques have become more important to help all program partners as they perform design tradeoffs and calculate energy savings for prototype houses built as part of the program. This document illustrates some of the analysis concepts proven effective and reliable for analyzing the transient energy usage of advanced energy systems as well as entire houses. The analysis procedure described here provides a starting point for calculating energy savings of a prototype house relative to two base cases: builder standard practice and regional standard practice. Also provides building simulation analysis to calculate annual energy savings based on side-by-side short-term field testing of a prototype house.
Date: October 29, 2001
Creator: Hendron, R.; Farrar-Nagy, S.; Anderson, R. & Judkoff, R.
Object Type: Report
System: The UNT Digital Library
Using Chemicals to Optimize Conformance Control in Fractured Reservoirs (open access)

Using Chemicals to Optimize Conformance Control in Fractured Reservoirs

This report describes work performed during the third and final year of the project, Using Chemicals to Optimize Conformance Control in Fractured Reservoirs. This research project had three objectives. The first objective was to develop a capability to predict and optimize the ability of gels to reduce permeability to water more than that to oil or gas. The second objective was to develop procedures for optimizing blocking agent placement in wells where hydraulic fractures cause channeling problems. The third objective was to develop procedures to optimize blocking agent placement in naturally fractured reservoirs.
Date: October 29, 2001
Creator: Seright, Randall S.; Liang, Jenn-Tai; Schrader, Richard; Hagstrom, John, II; Wang, Ying; Kumar, Ananad et al.
Object Type: Report
System: The UNT Digital Library
Automated real-time testing (ARTT) for embedded control systems (ECS). (open access)

Automated real-time testing (ARTT) for embedded control systems (ECS).

Developing real-time automated test systems for embedded control systems has been a real problem. Some engineers and scientists have used customized software and hardware as a solution, which can be very expensive and time consuming to develop. We have discovered how to integrate a suite of commercially available off-the-shelf software tools and hardware to develop a scalable test platform that is capable of performing complete black-box testing for a dual-channel real-time Embedded-PLC-based control system (www.aps.anl.gov). We will discuss how the Vali/Test Pro testing methodology was implemented to structure testing for a personnel safety system with large quantities of requirements and test cases.
Date: October 29, 2001
Creator: Hawkins, J.; Nguyen, H. & Howard, R.
Object Type: Article
System: The UNT Digital Library