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3-D Experimental Fracture Analysis at High Temperature

Description: T*e, which is an elastic-plastic fracture parameter based on incremental theory of plasticity, was determined numerically and experimentally. The T*e integral of a tunneling crack in 2024-T3 aluminum, three point bend specimen was obtained through a hybrid analysis of moire interferometry and 3-D elastic-plastic finite element analysis. The results were verified by the good agreement between the experimentally and numerically determined T*e on the specimen surface.
Date: September 14, 2001
Creator: Jackson, John H. & Kobayashi, Albert S.
Partner: UNT Libraries Government Documents Department

A 250-GHz CARM (Cyclotron Auto Resonance Maser) oscillator experiment driven by an induction linac

Description: A 250-GHz Cyclotron Auto Resonance Maser (CARM) oscillator has been designed and constructed and will be tested using a 1-kA, 2-MeV electron beam produced by the induction linac at the Accelerator Research Center (ARC) facility of Lawrence Livermore National Laboratory (LLNL). The oscillator circuit was made to operate in the TE{sub 11} mode at ten times cutoff using waveguide Bragg reflectors to create an external cavity Q of 8000. Theory predicts cavity fill times of less than 30 ns (pulse length) and efficiencies approaching 20% is sufficiently low transverse electron velocity spreads are maintained (2%).
Date: September 14, 1990
Creator: Caplan, M.; Kulke, B.; Bubp, D.G. (Lawrence Livermore National Lab., CA (USA)); McDermott, D. & Luhmann, N. (California Univ., Los Angeles, CA (USA))
Partner: UNT Libraries Government Documents Department

2004 Electron Donor Acceptor Interactions Gordon Conference - August 8-13, 2004

Description: The 2004 Gordon Conference on Donor/Acceptor Interactions will take place at Salve Regina University in Newport, Rhode Island on August 8-13, 2004. The conference will be devoted to the consequences of charge interaction and charge motion in molecular and materials systems.
Date: September 14, 2005
Partner: UNT Libraries Government Documents Department

2010 Census: Counting Americans Overseas as Part of the Census Would Not Be Feasible

Description: Testimony issued by the Government Accountability Office with an abstract that begins "The U.S. Census Bureau (Bureau) has typically excluded from the census private citizens residing abroad, but included overseas members of the military, federal civilian employees, and their dependents (in the 1990 and 2000 Censuses, these individuals were included in the numbers used for apportioning Congress). The Bureau recently tested the practicality of counting all overseas Americans. GAO was asked to testify on the test's initial results. Our statement is based on our published reports, one of which is being released at today's hearing."
Date: September 14, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

ABCXYZ: vector potential (A) and magnetic field (B) code (C) for Cartesian (XYZ) geometry using general current elements. [In LRL TRAN for CDC > 600 computer]

Description: ABCXYZ is a computer code for obtaining the Cartesian components of the vector potential and the magnetic field on an observed grid from an arrangement of current-carrying wires. Arbitrary combinations of straight line segments, arcs, and loops are allowed in the specification of the currents. Arbitrary positions and orientations of the current-carrying elements are also allowed. Specification of the wire diameter permits the computation of well-defined fields, even in the interiors of the conductors. An optical feature generates magnetic field lines. Extensive graphical and printed output is available to the user including contour, grid-line, and field-line plots. 12 figures, 1 table.
Date: September 14, 1976
Creator: Anderson, D. V.; Breazeal, J.; Finan, C. H. & Johnston, B. M.
Partner: UNT Libraries Government Documents Department

Acceptance test plan for the Waste Information Control System

Description: This document describes the acceptance test plan for the WICS system. The Westinghouse Hanford Company (WHC) Hazardous Material Control Group (HMC) of the 222-S Laboratory has requested the development of a system to help resolve many of the difficulties associated with tracking and data collection of containers and drums of waste. This system has been identified as Waste Information and Control System (WICS). The request for developing and implementing WICS has been made to the Automation and Simulation Engineering Group (ASE).
Date: September 14, 1994
Creator: Flynn, D. F.
Partner: UNT Libraries Government Documents Department

Accomplishments in Field Period Assembly for NCSX* This is how we did it

Description: The National Compact Stellarator Experiment (NCSX) was a collaborative effort between ORNL and PPPL. PPPL provided the assembly techniques with guidance from ORNL to meet design criteria. The individual vacuum vessel segments, modular coils, trim coils, and toroidal field coils components were delivered to the Field Period Assembly (FPA) crew who then would complete the component assemblies and then assemble the final three field period assemblies, each consisting of two sets of three modular coils assembled over a 120o vacuum vessel segment with the trim coils and toroidal field coils providing the outer layer. The requirements for positioning the modular coils were found to be most demanding. The assembly tolerances required for accurate positioning of the field coil windings in order to generate sufficiently accurate magnetic fields strained state of the art techniques in metrology and alignment and required constant monitoring of assembly steps with laser trackers, measurement arms, and photogrammetry. The FPA activities were being performed concurrently while engineering challenges were being resolved. For example, it was determined that high friction electrically isolated shims were needed between the modular coil interface joints and low distortion welding was required in the nose region of those joints. This took months of analysis and development yet the assembly was not significantly impacted because other assembly tasks could be performed in parallel with ongoing assembly tasks as well as tasks such as advance tooling setup preparation for the eventual welding tasks. The crew technicians developed unique, accurate time saving techniques and tooling which provided significant cost and schedule savings. Project management displayed extraordinary foresight and every opportunity to gain advanced knowledge and develop techniques was taken advantage of. Despite many risk concerns, the cost and schedule performance index was maintained nearly 1.0 during the assembly phase until project cancellation. In this paper, the ...
Date: September 14, 2009
Creator: Michael Viola, J. Edwards, T. Brown, L. Dudek, R. Ellis, P. Heitzenroeder, R. Strykowsky and Michael Cole
Partner: UNT Libraries Government Documents Department

Accuracy and reliability of China's energy statistics

Description: Many observers have raised doubts about the accuracy and reliability of China's energy statistics, which show an unprecedented decline in recent years, while reported economic growth has remained strong. This paper explores the internal consistency of China's energy statistics from 1990 to 2000, coverage and reporting issues, and the state of the statistical reporting system. Available information suggests that, while energy statistics were probably relatively good in the early 1990s, their quality has declined since the mid-1990s. China's energy statistics should be treated as a starting point for analysis, and explicit judgments regarding ranges of uncertainty should accompany any conclusions.
Date: September 14, 2001
Creator: Sinton, Jonathan E.
Partner: UNT Libraries Government Documents Department

Acoustic Probe for Solid-Gas-Liquid Suspension

Description: The primary objective of the research project during the first funding period was to develop an acoustic probe to measure volume percent solids in solid-liquid slurries in the presence of small amounts of gas bubbles. This problem was addressed because of the great need for a non-invasive, accurate and reliable method for solids monitoring in liquid slurries in the presence of radiolytically generated gases throughout the DOE complex. These measurements are necessary during mobilization of salts and sediments in tanks, transport of these slurries in transfer lines to processing facilities across a site, and, in some instances, during high level waste processing. Although acoustic probes have been commonly used for monitoring flows in single-phase fluids (McLeod, 1967), their application to monitor two-phase mixtures has not yet fully realized its potential. A number of investigators in recent years have therefore been involved in developing probes for measuring the volume fractions in liquid solid suspensions (Atkinson and Kytomaa, 1993; Greenwood et al., 1993; Martin et al., 1995) and in liquid-liquid suspensions (Bonnet and Tavlarides, 1987; Tavlarides and Bonnet, 1988, Yi and Tavlarides, 1990; Tsouris and Tavlarides, 1993, Tsouris et al., 1995). In particular, Atkinson and Kytomaa (1993) showed that the acoustic technique can be used to determine both the velocity and the volume fraction of solids while Martin et al. (1995) and Spelt et al. (1999) showed that the acoustic probe can also be used to obtain information on the size distribution of the particles. In a recent testing of in-line slurry monitors with radioactive slurries suspended with Pulsair Mixers (Hylton & Bayne, 1999), an acoustic probe did not compare well with other instruments most probably due to presence of entrained gases and improper acoustic frequency range of interrogation. The work of the investigators cited has established the potential of the acoustic ...
Date: September 14, 2003
Creator: Tavlarides, L.L. & Sangani, Ashok
Partner: UNT Libraries Government Documents Department

Actinide recovery from combustible waste: the Ce(IV)-NHO/sub 3/ system. Final report

Description: Actinides in ash can be leached effectively by refluxing with Ce(IV) in HNO/sub 3/; solubilization of actinide in ash was greater than or equal to 95% at ash concentrations to 30 g/l in stirred leachant. Plutonium and americium were the actinides present in the ash. Solubilized plutonium and americium were recovered from Ce(IV)-HNO/sub 3/ solution by solvent extraction. Extraction of plutonium into 30% tributyl phosphate in n-dodecane gave 99.99% recovery. The plutonium-depleted solution was then extracted with 30% dihexyl-N,N-diethylcarbamolylmethylenephosphonate (DHDECMP). Americium recovery was 99.64%. The Ce(IV)-HNO/sub 3/ system was compared with the HF-HNO/sub 3/ system now in common use. Advantages of the former included less equipment corrosion, no volatilization of silica, safe oxidation of carbon residues, minimal secondary waste (Ce is recycled), and better solubilization of actinide in the initial contact. However, additional contacts do not significantly improve solubilization, and a small fraction of actinide is not solubilized with Ce(IV)-HNO/sub 3/ that can be solubilized by HF-HNO/sub 3/. The effect of the fission product ruthenium on the dissolution of actinides in the Ce(IV)-HNO/sub 3/ system was investigated briefly, and a method for removing the ruthenium electrolytically was developed. Several process flowsheets were also considered. Actinide recovery requirements will suggest which of these might best be used. 6 figures, 7 tables.
Date: September 14, 1979
Creator: Thompson, G. H.; Childs, E. L.; Kochen, R. L.; Schmunk, R. H. & Smith, C. M.
Partner: UNT Libraries Government Documents Department

Activity of irradiated regular metal in buckets

Description: The potential of shipping a bucket of metal that has not had sufficient decay time is a common problem to all Reactor Processing Operations. The only method at present to assure shipping adequately decayed metal is by procedural control. This study was performed to determine the feasibility of establishing decay time for irradiated metal in buckets by radiation activity measurements.
Date: September 14, 1964
Creator: Smith, R. H.
Partner: UNT Libraries Government Documents Department

Adjustment of the (235)U Fission Spectrum

Description: The latest nuclear data are used to examine the sensitivity of the least squares adjustment of the {sup 235}U fission spectrum to the measured reaction rates, dosimetry cross sections, and prior spectrum covariance matrix. All of these parameters were found to be very important in the spectrum adjustment. The most significant deficiency in the nuclear data is the absence of a good prior covariance matrix. Covariance matrices generated from analytic models of the fission spectra have been used in the past. This analysis reveals some unusual features in the covariance matrix produced with this approach. Specific needs are identified for improved nuclear data to better determine the {sup 235}U spectrum. An improved {sup 235}U covariance matrix and adjusted spectrum are recommended for use in radiation transport sensitivity analyses.
Date: September 14, 1999
Partner: UNT Libraries Government Documents Department

[Advertisement for Star-Telegram Youth Spotlight]

Description: Photograph of three slides advertising the Star Telegram Youth Spotlight. The two slides on the left are facing the same direction but the slide on the right is facing the opposite direction. The slide on the left has a clipping from the Star Telegram. This clipping has the title of the column, "Fort Worth Star Telegram Youth Spotlight", with an illustration of a light in a black box at the top and a photograph below this in which two ladies wearing hats are visible. The bottom left corner of the slide has handwritten text that reads "Star-T TELOP #1". The middle slide features text that reads "Coming... Sept. 18 Star-Telegram" and the date is in white lettering while the other words are in black lettering. In the bottom left corner of the slide is handwritten text that reads "Star-T TELOP #2". The slide on the right has text that reads "Youth Spotlight" in narrow black letters. There is handwritten text in the top right corner of the slide that reads "Star-T TELOP #3".
Date: September 14, 1959
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Afghanistan Casualties: Military Forces and Civilians

Description: This report collects statistics from a variety of sources on casualties sustained during Operation Enduring Freedom (OEF), which began on October 7, 2001. OEF actions took place primarily in Afghanistan, but OEF casualties also include American casualties in other countries, listed within this report.
Date: September 14, 2010
Creator: Chesser, Susan G.
Partner: UNT Libraries Government Documents Department

Afghanistan: Narcotics and U.S. Policy

Description: This report provides current statistical information, profiles the Afghanistan narcotics trade's participants, explores linkages between narcotics, insecurity, and corruption, and reviews U.S. and international policy responses since late 2001. The report also considers ongoing policy debates regarding the counternarcotics role of coalition military forces, poppy eradication, alternative livelihoods, and funding issues for Congress.
Date: September 14, 2007
Creator: Blanchard, Christopher M.
Partner: UNT Libraries Government Documents Department

Afghanistan: Politics, Elections, and Government Performance

Description: This report discusses the current political state of Afghanistan, as well as the Afghan government. This report also discusses Afghanistan's relationship with the United States, particularly U.S. efforts to urge President Hamid Karzai to address corruption within the Afghan government.
Date: September 14, 2010
Creator: Katzman, Kenneth
Partner: UNT Libraries Government Documents Department

Agricultural and Environmental Input Parameters for the Biosphere Model

Description: This analysis is one of 10 technical reports that support the Environmental Radiation Model for Yucca Mountain Nevada (ERMYN) (i.e., the biosphere model). It documents development of agricultural and environmental input parameters for the biosphere model, and supports the use of the model to develop biosphere dose conversion factors (BDCFs). The biosphere model is one of a series of process models supporting the total system performance assessment (TSPA) for the repository at Yucca Mountain. The ERMYN provides the TSPA with the capability to perform dose assessments. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships between the major activities and their products (the analysis and model reports) that were planned in ''Technical Work Plan for Biosphere Modeling and Expert Support'' (BSC 2004 [DIRS 169573]). The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes the ERMYN and its input parameters.
Date: September 14, 2004
Creator: Rasmuson, K. & Rautenstrauch, K.
Partner: UNT Libraries Government Documents Department

Algebraic sub-structuring for electromagnetic applications

Description: Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, we show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.
Date: September 14, 2004
Creator: Yang, Chao; Gao, Weiguo; Bai, Zhaojun; Li, Xiaoye; Lee, Lie-Quan; Husbands, Parry et al.
Partner: UNT Libraries Government Documents Department

Algorithm for Computation of Electromagnetic Fields of An Accelerated Short Bunch Inside a Rectangular Chamber

Description: We discuss the feasibility of an application of an implicit finite-difference approximation to calculate the fields of a relativistic bunch moving with no restriction inside a vacuum chamber. We assume that a bunch trajectory is not straight but is inside a vacuum chamber or its branch. The bunch can be deflected by the fields of bending magnets. The bunch can be short enough to produce coherent synchrotron radiation (CSR). Accelerator physicists believe that electromagnetic phenomena of charged beams are governed by Maxwell's equations together with Newton's equations for particle dynamics. To understand the behavior of the beams and radiated fields we just need to find a solution to these equations for the case, which can fully describe the real accelerator environment. So, at first we make a model, which contains all the necessary components, but at the same time can be easily 'inserts' into the equations. Sometimes, it is possible to find analytical solutions, but usually they are only work for one-dimensional cases and rarer for two-dimension cases. To find a solution in general we may transform the equations into a equivalent finite-difference form and solve them using computers. We can find a lot of finite-difference schemes, which approximate Maxwell's equations since the first one that was published in 1966. Most of them are so called explicit schemes. That means that the value of the field at the new time step is calculated only by the field values at the previous time step. Stability conditions for these schemes do not allow a time step to be greater than or equal to a space (mesh) step. This limitation brings an additional troublesome effect for short wavelengths compared a mesh step. We state that this effect works like a frequency dispersion media, which is 'hidden' in the finite-difference equation.
Date: September 14, 2010
Creator: Novokhatski, Alexander & Sullivan, Michael
Partner: UNT Libraries Government Documents Department