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2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector

Description: There are five 2.5 MHz ferrite cavities (h = 28) in the Main Injector with an R/Q of 500 that are presently used for coalescing for the Tevatron. For use with the Fermilab Recycler, feedforward (FF) beam loading compensation (BLC) is required on these cavities because they will be required to operate at a net of 2 kV. Under current Recycler beam conditions, the beam-induced voltage is of this order. Recently a system using a digital bucket delay module operating at 53 MHz (h = 588) was used to produce a one-turn-delay feedforward signal. This signal was then combined with the low level RF signal to the 2.5 MHz cavities to cancel the beam induced voltage. During current operation they have shown consistently to operate with over a 20 dB reduction in beam loading.
Date: May 19, 2003
Creator: Dey, Joseph E.; Kourbanis, Ioanis & Steimel, James
Partner: UNT Libraries Government Documents Department
open access

3-D full waveform inversion of seismic data; Part I. Theory

Description: Full waveform inversion of seismic data is a challenging subject partly because of the lack of precise knowledge of the source. Since currently available approaches involve some form of approximations to the source, inversion results are subject to the quality and the choice of the source information used. A new full waveform inversion scheme has been introduced (Lee and Kim, 2003) using normalized wavefield for simple two-dimensional (2-D) scalar problems. The method does not require source information, so potential inversion errors due to source estimation may be eliminated. A gather of seismic traces is first Fourier-transformed into the frequency domain and a normalized wavefield is obtained for each trace in the frequency domain. Normalization is done with respect to the frequency response of a reference trace selected from the gather, so the complex-valued normalized wavefield is source-independent and dimensionless. The inversion algorithm minimizes misfits between measured normalized wavefield and numerically computed normalized wavefield. In this paper the full waveform inversion is extended to three-dimensional (3-D) problems.
Date: May 12, 2003
Creator: Lee, Ki Ha
Partner: UNT Libraries Government Documents Department
open access

''6-Degrees of Freedom'' Single Crystal Plasticity Experiments

Description: A deformation experiment has been developed specifically for the purpose of validation of dislocation dynamics simulations of plastic flow up to strains on the order of 1% [1]. The experiment has been designed so that a compressive uniaxial stress field is essentially super imposed on the test sample, and the crystal is free to deform with 3 orthogonal translation directions, and 3 rotation/tilt axes of freedom and has been given the name ''6-degrees of freedom'' (6DOF) experiment. The rotation, tilt and translation of the crystal are monitored by 5 laser displacement gages and 3 extensometers. Experiments are being performed on high purity Mo single crystals orientated for ''single slip''. All of the experiments are performed in pairs, with one test sample having highly polished surfaces for optical light and AFM slip-trace analyses, and the other having 4 strain gage rosettes mounted on the sides for measurement of the bi-axial surface strains during testing. All of the experimental data is used together to determine the slip activity of the orientated single crystal during deformation. Experimental results on high-purity Mo single crystals are presented. The results of these experiments show that slip behavior is in substantial deviation from the expected ''Schmid'' behavior. These experimental results bring into question some of the fundamental assumptions used in both the construction of crystal plasticity constitutive relationships and rules for dislocation mobility use in 3-D dislocation dynamics simulations.
Date: May 21, 2003
Creator: Lassila, D. H.; Florando, J. N.; LeBlanc, M. M.; Arsenlis, T. & Rhee, M.
Partner: UNT Libraries Government Documents Department
open access

An 8-Step Program: Shaping and Fixed-Time Food Delivery Effects on Several Approximations and Undesired Responses in Goats.

Description: This study investigated the effects of a shaping program for halter training across 8 steps in the program and 4 trial-terminating, or "undesirable," responses. Three La Mancha goats (Capra hircus) located at the Frank Buck Zoo in Gainesville, Texas were used for the study. A fixed-time 15 s (FT-15 s) was used during the baseline conditions, to examine the effects of response contingent and response-independent food deliveries, as well as to examine what preliminary steps might not necessarily have to be shaped. All 3 goats successfully learned to allow the halter to be placed on them and to lead on the halter, although 2 of the 3 goats required an additional task analysis for the fifth step to further break down that approximation. Several of the early steps selected by the researchers were not necessary to complete the program, as determined by the baseline condition.
Date: May 2003
Creator: Fernandez, Eduardo J.
Partner: UNT Libraries
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9-11 Commission Hearing #2, May 22, 2003, Part 1

Description: Recording of the second public hearing held by the National Commission on Terrorist Attacks Upon the United States on May 22, 2003 at the Hart Senate Office Building in Washington, D.C. This hearing addresses four topics, which include the commission mandate and objectives, intelligence oversight and the joint inquiry, affected constituencies, and the state of civil aviation security on September 11th. This section includes the first panel on the commission mandate and objectives, with testimony from Congresswoman Nancy Pelosi, Senator John McCain, and Senator Joseph Lieberman.
Date: May 22, 2003
Duration: 52 minutes 43 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #2, May 22, 2003, Part 2

Description: Recording of the second public hearing held by the National Commission on Terrorist Attacks upon the United States on May 22, 2003 at the Hart Office Senate Building in Washington, D.C. This hearing addresses four topics, which include the commission mandate and objectives, intelligence oversight and the joint inquiry, affected constituencies, and the state of civil aviation security on September 11th. This section includes the second panel on intelligence oversight and the joint inquiry with testimony from Senators Bob Graham and Richard Shelby and Representatives Porter Goss and Jane Harman.
Date: May 22, 2003
Duration: 1 hour 34 minutes 46 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #2, May 22, 2003, Part 3

Description: Recording of the second public hearing held by the National Commission on Terrorist Attacks upon the United States on May 22, 2003 at the Hart Senate Office Building in Washington, D.C. This hearing addresses four topics, which include the commission mandate and objectives, intelligence oversight and the joint inquiry, affected constituencies, and the state of civil aviation security on September 11th. This section contains the third panel on affected constituencies with testimony from Senators Schumer, Clinton, Corzine and Lautenberg, and Representatives Nadler, Shays, and Smith.
Date: May 22, 2003
Duration: 1 hour 23 minutes 23 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #2, May 22, 2003, Part # 4

Description: Recording of the second public hearing held by the National Commission on Terrorist Attacks upon the United States on May 22, 2003 at the Hart Senate Office Building in Washington, D.C. This hearing addresses four topics, which include the commission mandate and objectives, intelligence oversight and the joint inquiry, affected constituencies, and the state of civil aviation security on September 11th. This section includes the panel on civil aviation security with testimony from representatives of the Federal Aviation Administration, the Department of Transportation, the Air Transport Association of America, and the Transportation Security Agency.
Date: May 22, 2003
Duration: 2 hours 45 minutes 13 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #2, May 23, 2003, Part 1

Description: Recording of the second public hearing held by the National Commission on Terrorist Attacks upon the United States on May 23 in Washington, D.C. This hearing addresses four topics, which include the commission mandate and objectives, intelligence oversight and the joint inquiry, affected constituencies, and the state of civil aviation security on September 11th. This section includes the panel on civil aviation security, with testimony from Norman Mineta, Major General Craig McKinley, and Lieutenant General Mike Canavan on the attacks and the response to the 9/11 attacks.
Date: May 23, 2003
Duration: 2 hours 6 minutes 47 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
captions transcript

9-11 Commission Hearing #2, May 23, 2003, Part 2

Description: Recording of the second public hearing held by the National Commission on Terrorist Attacks upon the United States on May 23, 2003 in Washington, D.C. This hearing addresses four topics, which include the commission mandate and objectives, intelligence oversight and the joint inquiry, affected constituencies, and the state of civil aviation security on September 11th. This section concludes the panel on civil aviation security, with testimony from Stephen McHale, Major General O.K. Steele, and Mary Schiavo on reforming civil aviation security.
Date: May 23, 2003
Duration: 2 hours 31 minutes 29 seconds
Creator: National Commission on Terrorist Attacks upon the United States
Partner: UNT Libraries Government Documents Department
open access

53 MHZ Feedforward beam loading compensation in the Fermilab main injector

Description: 53 MHz feedforward beam loading compensation is crucial to all operations of the Main Injector. Recently a system using a fundamental frequency down converter mixer, a digital bucket delay module and a fundamental frequency up converter mixer were used to produce a one-turn-delay feedforward signal. This signal was then combined with the low level RF signal to the cavities to cancel the transient beam induced voltage. During operation they have shown consistently over 20 dB reduction in side-band voltage around the fundamental frequency during Proton coalescing and over 14 dB in multi-batch antiproton coalescing.
Date: May 19, 2003
Creator: al., Joseph E Dey et
Partner: UNT Libraries Government Documents Department
open access

A 201 MHz RF cavity design with non-stressed pre-curved Be windows for muon cooling channels

Description: We present a 201-MHz RF cavity design for muon cooling channels with non-stressed and pre-curved Be foils to terminate the beam apertures. The Be foils are necessary to improve the cavity shunt impedance with large beam apertures needed for accommodating large transverse size muon beams. Be is a low-Z material with good electrical and thermal properties. It presents an almost transparent window to muon beams, but terminates the RF cavity electro-magnetically. Previous designs use pre-stressed flat Be foils in order to keep cavity from detuning resulted from RF heating on the window surface. Be foils are expensive, and it is difficult to make them under desired tension. An alternative design is to use precurved and non-stressed Be foils where the buckling direction is known, and frequency shifts can be properly predicted. We will present mechanical simulations on the Be foils in this paper.
Date: May 1, 2003
Creator: Li, Derun; Ladran, A.; Staples, J.; Virostek, S.; Zisman, M.; Lau, W. et al.
Partner: UNT Libraries Government Documents Department
open access

2002 Chemical Engineering Division annual report.

Description: The Chemical Engineering Division is one of eight engineering research divisions within Argonne National Laboratory, one of the U.S. government's oldest and largest research laboratories. The University of Chicago oversees the laboratory on behalf of the U.S. Department of Energy (DOE). Argonne's mission is to conduct basic scientific research, to operate national scientific facilities, to enhance the nation's energy resources, and to develop better ways to manage environmental problems. Argonne has the further responsibility of strengthening the nation's technology base by developing innovative technology and transferring it to industry. The Division is a diverse early-stage engineering organization, specializing in the treatment of spent nuclear fuel, development of advanced electrochemical power sources, and management of both high- and low-level nuclear wastes. Although this work is often indistinguishable from basic research, our efforts are directed toward the practical devices and processes that are covered by Argonne's mission. Additionally, the Division operates the Analytical Chemistry Laboratory; Environment, Safety, and Health Analytical Chemistry services; and Dosimetry and Radioprotection services, which provide a broad range of analytical services to Argonne and other organizations. The Division is multidisciplinary. Its people have formal training as ceramists; physicists; material scientists; electrical, mechanical, chemical, and nuclear engineers; and chemists. They have experience working in academia; urban planning; and the petroleum, aluminum, and automotive industries. Their skills include catalysis, ceramics, electrochemistry, metallurgy, nuclear magnetic resonance spectroscopy, and petroleum refining, as well as the development of nuclear waste forms, batteries, and high-temperature superconductors. Our wide-ranging expertise finds ready application in solving energy and environmental problems. Division personnel are frequently called on by governmental and industrial organizations for advice and contributions to problem solving in areas that intersect present and past Division programs and activities.
Date: May 22, 2003
Creator: Lewis, D.; Graziano, D. & Miller, J. F.
Partner: UNT Libraries Government Documents Department
open access

3D Computations and Experiments

Description: This project is in its first full year after the combining of two previously funded projects: ''3D Code Development'' and ''Dynamic Material Properties''. The motivation behind this move was to emphasize and strengthen the ties between the experimental work and the computational model development in the materials area. The next year's activities will indicate the merging of the two efforts. The current activity is structured in two tasks. Task A, ''Simulations and Measurements'', combines all the material model development and associated numerical work with the materials-oriented experimental activities. Task B, ''ALE3D Development'', is a continuation of the non-materials related activities from the previous project.
Date: May 12, 2003
Creator: Couch, R; Faux, D; Goto, D & Nikkel, D
Partner: UNT Libraries Government Documents Department
open access

Abortion: Legislative Response

Description: The primary focus of this issue brief is legislative action in the 108th Congress with respect to abortion. However, discussion of those legislative proposals necessarily involves a brief discussion of the leading U.S. Supreme Court decisions concerning a woman’s right to choose whether to terminate her pregnancy. For a more detailed discussion of the relevant case law, see CRS Report 95-724, Abortion Law Development: A Brief Overview.
Date: May 9, 2003
Creator: Lewis, Karen J.; Shimabukuro, Jon O. & Ely, Dana
Partner: UNT Libraries Government Documents Department
open access

An Abstract Description Approach to the Discovery and Classification of Bioinformatics Web Sources

Description: The World Wide Web provides an incredible resource to genomics researchers in the form of dynamic data sources--e.g. BLAST sequence homology search interfaces. The growth rate of these sources outpaces the speed at which they can be manually classified, meaning that the available data is not being utilized to its full potential. Existing research has not addressed the problems of automatically locating, classifying, and integrating classes of bioinformatics data sources. This paper presents an overview of a system for finding classes of bioinformatics data sources and integrating them behind a unified interface. We examine an approach to classifying these sources automatically that relies on an abstract description format: the service class description. This format allows a domain expert to describe the important features of an entire class of services without tying that description to any particular Web source. We present the features of this description format in the context of BLAST sources to show how the service class description relates to Web sources that are being described. We then show how a service class description can be used to classify an arbitrary Web source to determine if that source is an instance of the described service. To validate the effectiveness of this approach, we have constructed a prototype that can correctly classify approximately two-thirds of the BLAST sources we tested. We then examine these results, consider the factors that affect correct automatic classification, and discuss future work.
Date: May 1, 2003
Creator: Rocco, D & Critchlow, T J
Partner: UNT Libraries Government Documents Department
open access

Accelerated Stress Testing of Thin-Film Modules with SnO2:F Transparent Conductors

Description: This paper reviews a testing program conducted at NREL for the past two years that applied voltage, water vapor, and light stresses to thin-film photovoltaic (PV) modules with SnO2:F transparent conducting oxides (TCOs) deposited on soda-lime glass superstrates. Electrochemical corrosion at the glass-TCO interface was observed to result in delamination of the thin-film layers. Experimental testing was directed toward accelerating the corrosion and understanding the nature of the resulting damage.
Date: May 1, 2003
Creator: Osterwald, C. R.; McMahon, T. J.; del Cueto, J. A.; Adelstein, J. & Puett, J.
Partner: UNT Libraries Government Documents Department
open access

Accelerator Magnet Plugging By Metal Oxides: A Theoretical Investigation, Remediation, and Preliminary Results

Description: The Thomas Jefferson National Accelerator Facility has experienced magnet overheating at high power. Overheating is caused by cooling water passages becoming plugged and is a direct result of the Dean Effect deposition of corrosion products suspended in the water. Salving simplified dynamic model equations of the flow in the magnet tubing bends yielded a relationship for plugging rate as a function of particle size, concentration, velocity, channel width and bend radius. Calculated deposition rates using data from a previous study are promising. Remediation has consisted of submicron filtration, magnet cleaning, and dissolved oxygen removal. Preliminary results are good: no accelerator outages have been attributed to magnet plugging since the remediation has been completed.
Date: May 1, 2003
Creator: Rust, William W.
Partner: UNT Libraries Government Documents Department
open access

Accelerator related backgrounds in the LHC forward detectors

Description: Detailed Monte Carlo simulations are performed on radiation environment in the LHC IP5 interaction region at the locations of the TOTEM Roman Pots proposed to detect particles produced at very small angles in the elastic scattering and diffraction dissociation processes at the LHC. Radiation loads on these detectors are calculated with the MARS14 code both of the pp-collision origin and beam loss related (beam-gas and tails from collimators).
Date: May 28, 2003
Creator: al., Nikolai V. Mokhov et
Partner: UNT Libraries Government Documents Department
open access

Accessing Information on the World Wide Web: Predicting Usage Based on Involvement

Description: Advice for Web designers often includes an admonition to use short, scannable, bullet-pointed text, reflecting the common belief that browsing the Web most often involves scanning rather than reading. Literature from several disciplines focuses on the myriad combinations of factors related to online reading but studies of the users' interests and motivations appear to offer a more promising avenue for understanding how users utilize information on Web pages. This study utilized the modified Personal Involvement Inventory (PII), a ten-item instrument used primarily in the marketing and advertising fields, to measure interest and motivation toward a topic presented on the Web. Two sites were constructed from Reader's Digest Association, Inc. online articles and a program written to track students' use of the site. Behavior was measured by the initial choice of short versus longer versions of the main page, the number of pages visited and the amount of time spent on the site. Data were gathered from students at a small, private university in the southwest part of the United States to answer six hypotheses which posited that subjects with higher involvement in a topic presented on the Web and a more positive attitude toward the Web would tend to select the longer text version, visit more pages, and spend more time on the site. While attitude toward the Web did not correlate significantly with any of the behavioral factors, the level of involvement was associated with the use of the sites in two of three hypotheses, but only partially in the manner hypothesized. Increased involvement with a Web topic did correlate with the choice of a longer, more detailed initial Web page, but was inversely related to the number of pages viewed so that the higher the involvement, the fewer pages visited. An additional indicator of usage, the average amount …
Date: May 2003
Creator: Langford, James David
Partner: UNT Libraries
open access

Accounting Reform After Enron: Issues in the 108th Congress

Description: This report discusses the anxieties within Congress in the wake of the Enron scandal. Moreover, the report notes that the 108th Congress is not likely to pass legislative reform as extreme as the 107th Congress, but will still confront issues of accounting reform. The report also highlights what the 108th Congress plans to reform.
Date: May 28, 2003
Creator: Jickling, Mark
Partner: UNT Libraries Government Documents Department
open access

Acculturative Processes and Their Impact on Self-Reports of Psychological Distress in Mexican-American Adolescents

Description: The current study examined the effects of acculturative processes on the self-report of behavioral problems in Hispanic children ages 11-14. Acculturation was measured by the Acculturation Rating Scale for Mexican Americans-II (ARSMA-II) (ã Sage Publications, Thousand Oaks, CA, www.sagepub.com) (Cuellar, Arnold, and Maldonado, 1995) and the self-report of behavioral symptoms was assessed using the Youth Self-Report (ã T.M. Achenbach, Burlington, VT, www.aseba.com) (Achenbach, 1991). It was hypothesized that while both the linear and orthogonal categories of acculturation would account for a significant proportion of the variance in behavior problems in this age group, the orthogonal model would account for a larger proportion of variance due to its multidimensional nature. As well, it was hypothesized that the experimental Marginalization scales of the ARSMA-II would be predictive of behavioral problems. Multivariate analysis of variance was used to test these hypotheses and results were non-significant for the linear, orthogonal, and marginalization categories. The effects of the ethnic/cultural homogeneity of the region from which the sample was drawn, the buffering of social support, and the developmental aspects of ethnic identity are discussed as factors which may have influenced the potential impact of acculturative stress on psychological and behavioral functioning.
Date: May 2003
Creator: Garrison, Lance A.
Partner: UNT Libraries
open access

Achieving Order through CHAOS: the LLNL HPC Linux Cluster Experience

Description: Since fall 2001, Livermore Computing at Lawrence Livermore National Laboratory has deployed 11 Intel IA-32-based Linux clusters ranging in size up to 1154 nodes. All provide a common programming model and implement a similar cluster architecture. Hardware components are carefully selected for performance, usability, manageability, and reliability and are then integrated and supported using a strategy that evolved from practical experience. Livermore Computing Linux clusters run a common software environment that is developed and maintained in-house while drawing components and additional support from the open source community and industrial partnerships. The environment is based on Red Hat Linux and adds kernel modifications, cluster system management, monitoring and failure detection, resource management, authentication and access control, development environment, and parallel file system. The overall strategy has been successful and demonstrates that world-class high-performance computing resources can be built and maintained using commodity off-the-shelf hardware and open source software.
Date: May 2, 2003
Creator: Braby, R L; Garlick, J E & Goldstone, R J
Partner: UNT Libraries Government Documents Department
open access

ACME: Algorithms for Contact in a Multiphysics Environment API Version 1.3

Description: An effort is underway at Sandia National Laboratories to develop a library of algorithms to search for potential interactions between surfaces represented by analytic and discretized topological entities. This effort is also developing algorithms to determine forces due to these interactions for transient dynamics applications. This document describes the Application Programming Interface (API) for the ACME (Algorithms for Contact in a Multiphysics Environment) library.
Date: May 1, 2003
Creator: BROWN, KEVIN H.; VOTH, THOMAS E.; GLASS, MICHEAL W.; GULLERUD, ARNE S.; HEINSTEIN, MARTIN W. & JONES, REESE E.
Partner: UNT Libraries Government Documents Department
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