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Investigation into the repetition-rate limitations of magnetic switches

Description: The use of magnetic switches to generate high power pulses has opened up a whole new spectrum of possibilities. Here we describe an investigation into the maximum repetition rates possible with these devices.
Date: February 10, 1982
Creator: Birx, D. L.; Reginato, L. L. & Schmidt, J. A.
Partner: UNT Libraries Government Documents Department
open access

Overlapping Schwarz for Nonlinear Problems. An Element Agglomeration Nonlinear Additive Schwarz Preconditioned Newton Method for Unstructured Finite Element Problems

Description: This paper extends previous results on nonlinear Schwarz preconditioning ([4]) to unstructured finite element elliptic problems exploiting now nonlocal (but small) subspaces. The non-local finite element subspaces are associated with subdomains obtained from a non-overlapping element partitioning of the original set of elements and are coarse outside the prescribed element subdomain. The coarsening is based on a modification of the agglomeration based AMGe method proposed in [8]. Then, the alge… more
Date: February 10, 2005
Creator: Cai, X C; Marcinkowski, L & Vassilevski, P S
Partner: UNT Libraries Government Documents Department
open access

A method for quick assessment of CO2 storage capacity in closed and semi-closed saline formations

Description: Saline aquifers of high permeability bounded by overlying/underlying seals may be surrounded laterally by low-permeability zones, possibly caused by natural heterogeneity and/or faulting. Carbon dioxide (CO{sub 2}) injection into and storage in such 'closed' systems with impervious seals, or 'semi-closed' systems with nonideal (low-permeability) seals, is different from that in 'open' systems, from which the displaced brine can easily escape laterally. In closed or semi-closed systems, the pres… more
Date: February 10, 2008
Creator: Zhou, Q.; Birkholzer, J.; Tsang, C. F. & Rutqvist, J.
Partner: UNT Libraries Government Documents Department
open access

Risks of Mortality and Morbidity from Worldwide Terrorism: 1968-2004

Description: Worldwide data on terrorist incidents between 1968 and 2004 gathered by the RAND corporation and the Oklahoma City National Memorial Institute for the Prevention of Terrorism (MIPT) were assessed for patterns and trends in morbidity/mortality. Adjusted data analyzed involve a total of 19,828 events, 7,401 ''adverse'' events (each causing {ge}1 victim), and 86,568 ''casualties'' (injuries) of which 25,408 were fatal. Most terror-related adverse events, casualties and deaths involved bombs and gu… more
Date: February 10, 2005
Creator: Bogen, K. T. & Jones, E. D.
Partner: UNT Libraries Government Documents Department
open access

Why every national deep-geological-isolation program needs a long-term science & technology component

Description: The objective of this paper is to set down the rationale for a separate Science & Technology (S&T) Program within every national deep-geological-isolation program. The fundamental rationale for such a Program is to provide a dedicated focus for longer-term science and technology activities that ultimately will benefit the whole repository mission. Such a Program, separately funded and with a dedicated staff (separate from the ''mainline'' activities to develop the repository, the surface fa… more
Date: February 10, 2006
Creator: Budnitz, R J
Partner: UNT Libraries Government Documents Department
open access

Supersymmetry, Naturalness, and Signatures at the LHC

Description: Weak scale supersymmetry is often said to be fine-tuned, especially if the matter content is minimal. This is not true if there is a large A term for the top squarks. We present a systematic study on fine-tuning in minimal supersymmetric theories and identify low energy spectra that do not lead to severe fine-tuning. Characteristic features of these spectra are: a large A term for the top squarks, small top squark masses, moderately large tan {beta}, and a small {mu} parameter. There are classe… more
Date: February 10, 2006
Creator: Kitano, Ryuichiro & Nomura, Yasunori
Partner: UNT Libraries Government Documents Department
open access

Microanalytical Methods for Bio-Forensics Investigations

Description: Forensics investigations of bio-crime or bio-terrorism incidents require careful analysis of collected evidentiary material. Although the biological markers in the evidentiary material are important (e.g. genomic signatures, protein markers), the elemental make-up of the organisms themselves and the surrounding non-biological material is extremely useful for attributing a specific process and, perhaps, specific persons to the production of the biological agent. This talk will describe the coord… more
Date: February 10, 2006
Creator: Brewer, L N; Weber, P K; Grant, R P; Ghosal, S & Michael, J R
Partner: UNT Libraries Government Documents Department
open access

The dynamical behavior of classifier systems

Description: Classifier systems are quite complicated, in terms of both their components and behavior. This complexity is understandable given the wide spectrum of activity they are intended to model. Unfortunately, the complexity of these systems also makes it difficult to understand them analytically. Previous analysis has focused on specific components of the classifier system, for example, the genetic algorithm or the bucket brigade. The lack of a unified theory has led users of these systems to rely on… more
Date: February 10, 1989
Creator: Forrest, S. & Miller, J.H.
Partner: UNT Libraries Government Documents Department
open access

Seismic margin reviews of nuclear power plants: Identification of important functions and systems

Description: The purpose of this paper is to present the basis and method used for the development of the systems screening portion of the seismic margin review methodology. The results from the review of seven utility-sponsored seismic PRA's and one Seismic Safety Margins Research Program Study have been used to develop some insights regarding the importance of various systems and functions to seismic margins. (JDH)
Date: February 10, 1987
Creator: Prassinos, P. G.; Moore, D. L. & Amico, P. J.
Partner: UNT Libraries Government Documents Department
open access

Structural design considerations in the Mirror Fusion Test Facility (MFTF-B) vacuum vessel

Description: In view of favorable results from the Tandem Mirror Experiment (TMX) also at LLNL, the MFTF project is now being rescoped into a large tandem mirror configuration (MFTF-B), which is the mainline approach to a mirror fusion reactor. This paper concerns itself with the structural aspects of the design of the vessel. The vessel and its intended functions are described. The major structural design issues, especially those influenced by the analysis, are described. The objectives of the finite eleme… more
Date: February 10, 1981
Creator: Vepa, Kosla & Sterbentz, William H.
Partner: UNT Libraries Government Documents Department
open access

Modular TPC's for relativistic heavy ion experiments

Description: We have developed a TPC system for use in relativistic heavy ion experiments that permits the efficient reconstruction of high multiplicity events including events with decay vertices. It operates with the beam through the middle of the chamber giving good efficiency, two-track separation and spatial resolution. The three-dimensional points in this system allow the reconstruction of the complex events of interest. The use of specially developed hybrid electronics allows us to build a compact an… more
Date: February 10, 1989
Creator: Etkin, A.; Eiseman, S. E.; Foley, K. J.; Hackenburg, R. W.; Longacre, R. S.; Love, W. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Neutron detectors for fusion reaction-rate measurements

Description: Fusion reactions in an inertial-confinement fusion (ICF) target filled with deuterium or a deuterium/tritium fuel release nearly monoenergetic neutrons. Because most the neutrons leave the compressed target without collision, they preserve reaction-rate information as they travel radially outward from their point of origin. Three fast, neutron detector techniques, each capable of measuring the fusion reaction-rate of ICF targets, have been demonstrated. The most advanced detector is based on th… more
Date: February 10, 1994
Creator: Lerche, R. A.; Phillion, D. W.; Landen, O. L.; Murphy, T. J. & Jaanimagi, P. A.
Partner: UNT Libraries Government Documents Department
open access

Greenhouse gas emission impacts of electric vehicles under varying driving cycles in various counties and US cities

Description: Electric vehicles (EVs) can reduce greenhouse gas emissions, relative to emissions from gasoline-fueled vehicles. However, those studies have not considered all aspects that determine greenhouse gas emissions from both gasoline vehicles (GVs) and EVs. Aspects often overlooked include variations in vehicle trip characteristics, inclusion of all greenhouse gases, and vehicle total fuel cycle. In this paper, we estimate greenhouse gas emission reductions for EVs, including these important aspects.… more
Date: February 10, 1994
Creator: Wang, M. Q. & Marr, W. W.
Partner: UNT Libraries Government Documents Department
open access

On the Possibility of the Sheath-Driven, Finite-Beta Modes Localized Near the Divertor Plate

Description: It is shown that, in a finite beta plasma, there may exist sheath driven modes whose amplitude decreases exponentially with the distance from the divertor plate. The modes are sensitive to the radial tilt of the divertor plate. The short-wavelength branch of the instability, with the cross-field wavelength Dof order of a few ion gyroradii, is present in the case of a ''positive'' tilt of the divertor plate, whereas the long-wavelength branch, with D of order of 10 or so gyroradii is unstable fo… more
Date: February 10, 2005
Creator: Cohen, R & Ryutov, D
Partner: UNT Libraries Government Documents Department
open access

Source fabrication and lifetime for Li{sup +} ion beams extracted from alumino-silicate sources

Description: A space-charge-limited beam with current densities (J) exceeding 1 mA/cm{sup 2} have been measured from lithium alumino-silicate ion sources at a temperature of ∼1275{degrees}C. At higher extraction voltages, the source appears to become emission limited with J ≥ 1.5 mA/cm{sup 2}, and J increases weakly with the applied voltage. A source with an alumino-silicate coating 6.35 mm in diameter and ≤0.25 mm thick, has a lifetime of ∼40 hours at ∼1275{degrees}C, when pulsed at 0.05 Hz and with pulse … more
Date: February 10, 2012
Creator: Greenway, W. G. & Kwan, J. W.
Partner: UNT Libraries Government Documents Department
open access

Extreme Ultraviolet Laser-based Table-top Aerial Image Metrology of Lithographic Masks

Description: We report the first at-wavelength line edge roughness measurements of patterned EUV lithography masks realized using a table-top aerial imaging system based on a table-top {lambda}=13.2 laser.
Date: February 10, 2010
Creator: Brizuela, F.; Carbajo, S.; Sakdinawat, A.; Wang, Y.; Alessi, D.; Martz, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Multiband Charge-Coupled Device

Description: No Description Available.
Date: February 10, 2014
Creator: Chang, Chu-En; Segal, Julie D.; Roodman, Aaron J.; Howe, Roger T. & Kenney, Christopher J.
Partner: UNT Libraries Government Documents Department
open access

Corrosion and ESCA studies of uranium after exposure to an RF discharge

Description: Corrosion of uranium in O/sub 2/ or H/sub 2/O atmospheres can be inhibited by first oxidizing the surface and then exposing it to organic vapors at temperatures near 400/sup 0/C. There is evidence that a polymeric material is formed on the surface and that it may be responsible for the corrosion inhibition. Polymer coatings can also be prepared using an RF discharge. This paper describes experiments in which uranium surfaces were exposed to an RF discharge and then evaluated as to their corrosi… more
Date: February 10, 1977
Creator: Happe, J. A.; Colmenares, C. A.; McCreary, T. & Somorjai, G. A.
Partner: UNT Libraries Government Documents Department
open access

Effects of shield impedance, connector resistance, and coaxial inductors on ground noise interference in nuclear reactor instrumentation systems

Description: Electrical noise interference in low-level (approximately 50 ..mu..V), wide band (approximately 15 MHz) flux monitoring systems applied to nuclear reactor control causes safety and reliability problems. Others have shown that one predominant source of noise interference is conduction of currents in instrument cable shields and building conduits. Since these currents produce noise that is similar to signals produced by nuclear detectors, such noise interference reduces the ability of a reactor i… more
Date: February 10, 1976
Creator: Burns, R. S.
Partner: UNT Libraries Government Documents Department
open access

BPM Breakdown Potential in the PEP-II B-factory Storage Ring Collider

Description: High current B-Factory BPM designs incorporate a button type electrode which introduces a small gap between the button and the beam chamber. For achievable currents and bunch lengths, simulations indicate that electric potentials can be induced in this gap which are comparable to the breakdown voltage. This study characterizes beam induced voltages in the existing PEP-II storage ring collider BPM as a function of bunch length and beam current.
Date: February 10, 2010
Creator: Weathersby, Stephen & Novokhatski, Alexander
Partner: UNT Libraries Government Documents Department
open access

Performance Analysis of Mechanical Draft Cooling Tower

Description: Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has cross-flow and counter-current MDCT's consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to simulate the cooling tower performance for … more
Date: February 10, 2009
Creator: Lee, S.; Alfred Garrett, A.; James02 Bollinger, J. & Larry Koffman, L.
Partner: UNT Libraries Government Documents Department
open access

HOM Sensitivity in the PEP-II HER Vacuum Chamber

Description: Synchrotron radiation is the main source of vacuum chamber heating in the PEP-II storage ring collider. This heating is reduced substantially as lattice energy is lowered. Energy scans over {Upsilon} energy states were performed by varying the high energy ring (HER) lattice energy at constant gap voltage and frequency. We observed unexpected temperature rise at particular locations when HER lattice energy was lowered from 8.6 GeV ({Upsilon}(3S)) to 8.0 GeV ({Upsilon}(2S)) while most other tempe… more
Date: February 10, 2010
Creator: Weathersby, Stephen; Novokhatski, Alexander & Sullivan, Mike
Partner: UNT Libraries Government Documents Department
open access

An Exact SU(2) Symmetry and Persistent Spin Helix in a Spin-Orbit Coupled System

Description: Spin-orbit coupled systems generally break the spin rotation symmetry. However, for a model with equal Rashba and Dresselhauss coupling constant (the ReD model), and for the [110] Dresselhauss model, a new type of SU(2) spin rotation symmetry is discovered. This symmetry is robust against spin-independent disorder and interactions, and is generated by operators whose wavevector depends on the coupling strength. It renders the spin lifetime infinite at this wavevector, giving rise to a Persisten… more
Date: February 10, 2010
Creator: Bernevig, Andrei
Partner: UNT Libraries Government Documents Department
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