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The Relationship Between Student Evaluation of Instruction and Selected Predictors

Description: The study attempted to determine the relationship between student evaluation of instruction and institutional performance ratings with the following predictors: faculty job satisfaction, faculty attitudes toward the evaluation process, faculty attitudes toward factors associated with the evaluation process, and faculty characteristics.
Date: December 1992
Creator: Anderson, S. Eric (Steven Eric)
Partner: UNT Libraries

Exploiting the power of DSM and SMP clusters for parallel CFD

Description: The new generation of powerful DSM and SMP cluster computers enables simulations of fluid dynamics at sufficient resolution to compute the complex nonlinear interactions of small-scale turbulent motions with a large-scale driving flow. With a new programming model of hierarchical shared memory multitasking, it is possible to exploit these new systems without disrupting the flow of small and medium-sized jobs that makes their existence possible.
Date: March 15, 1999
Creator: Anderson, S. E.; Cohen, R. H.; Curtis, B. C.; Dannevik, W. P.; Dimits, A. M.; Dinge, D. et al.
Partner: UNT Libraries Government Documents Department

Stratigraphic data for wells at and near the Idaho National Engineering Laboratory, Idaho

Description: A stratigraphic data base containing 230 stratigraphic units in 333 wells was constructed for deposits that make up the unsaturated zone and the Snake River Plain aquifer at and near INEL in eastern Idaho. Stratigraphic units, which were identified and correlated using data from numerous outcrops, 26 continuous cores, and 328 natural-gamma logs available in Dec. 1993, include 121 basalt-flow groups, 102 sedimentary interbeds, 6 andesite-flow groups, and 1 rhyolite dome. By volume, basalt flows make up about 90% of the deposits underlying most of this 890 mi{sup 2} area. Basalt, sediment, andesite, and rhyolite were identified from outcrops and cores that were selectively evaluated. Stratigraphic units were correlated using these data and natural-gamma logs. Best correlations were for basalt and sediment at Test Area North, the Naval Reactors Area, the Test Reactor Area, ICPP, and the Radioactive Waste Management Complex (RWMC), where most cores and 2/3 of the logs were obtained. Correlations range from good at the RWMC to uncertain the eastern half of the study area. A computer diskette containing the data is included.
Date: May 1, 1996
Creator: Anderson, S. R.; Ackerman, D. J.; Liszewski, M. J. & Frieburger, R. M.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, October 1995--December 1995

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. As an aide in this characterization, which is by no means straightforward, another objective is to combine this technique with volumetric adsorption techniques and track the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. In terms of the primary objectives of the project, the {sup 129}Xe NMR spectra with pressure variation have been obtained for two more coals, completing this task for the sample set of six coals. In terms of the broad objectives of the project, examination of the influence on the xenon signal of packing the powdered coal has been undertaken. These data are of potential value for the determination of whether the porosity is open or closed. Results of powder density and related experiments will be used in the final interpretation of our current data, including the determination of whether, in the NMR of loose powdered, the chemical shift is indicative of the ``true`` gas-solid interaction.
Date: December 31, 1995
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, January 1996--March 1996

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. Another objective is to use this technique to describe the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. During this quarter, we have: (i) investigated particle size effect on the chemical shift of xenon adsorbed in a set of size-graded vitrinites; (ii) tracked the progress of xenon adsorption via xenon NMR, including particle size effect on the adsorption process; (iii) completed a preliminary test for chemical shift anisotropy in coal; and (iv) examined a microporous carbon by {sup 129}Xe NMR after two cycles of oxygen chemisorption/desorption.
Date: August 1, 1996
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Technical progress report, September 1994--October 1995

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. As an aide in this characterization, another objective is to combine this technique with volumetric adsorption techniques and track the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. In terms of the primary objectives of the project, the {sup 129}Xe NMR spectra with pressure variation have been completed for four coals, and N{sub 2} and C0{sub 2} adsorption isotherms with surface area measurement have been completed for three coals. A microporous carbon has been subjected to one oxygen chemisorption/desorption cycle and examined by {sup 129}Xe NMR.
Date: December 31, 1995
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Thickness of surficial sediment at and near the Idaho National Engineering Laboratory, Idaho

Description: Thickness of surficial sediment was determined from natural-gamma logs in 333 wells at and near the Idaho National Engineering Laboratory in eastern Idaho to provide reconnaissance data for future site-characterization studies. Surficial sediment, which is defined as the unconsolidated clay, silt, sand, and gravel that overlie the uppermost basalt flow at each well, ranges in thickness from 0 feet in seven wells drilled through basalt outcrops east of the Idaho Chemical Processing Plant to 313 feet in well Site 14 southeast of the Big Lost River sinks. Surficial sediment includes alluvial, lacustrine, eolian, and colluvial deposits that generally accumulated during the past 200 thousand years. Additional thickness data, not included in this report, are available from numerous auger holes and foundation borings at and near most facilities.
Date: June 1, 1996
Creator: Anderson, S. R.; Liszewski, M. J. & Ackerman, D. J.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, April 1996--June 1996

Description: Objective is to use {sup 129}Xe NMR to study the microporous structure of coals. During this quarter, we have: performed a presaturation experiment on Wyodak subbituminous coal, monitored the progress of Xe adsorption in an anthracite, focusing on the changes observed in the external-surface adsorbed gas signal, used an echo sequence to obtain {sup 129}Xe NMR spectra of Blind Canyon hvAb coal, and improved and repeated the successive oxygen adsorption and desorption experiment on a microporous carbon.
Date: November 1, 1996
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, July 1996--September 1996

Description: The primary objective of this project is to use {sup 129}Xe NMR to characterize the microporous structure of coals. We will use direct information on pore size, as well as indirect information from adsorption rates and evidence for intra/extraparticle diffusion, to characterize the connectivity of the micropore network. A second objective is to use {sup 129}Xe NMR to describe the effect of controlled opening of the micropores in a microporous carbon by oxygen chemi-sorption/desorption. Our experimental focus in this quarter has been the low power presaturation of the NMR signal of {sup 129}Xe adsorbed in coal. Preliminary work on this experiment was reported in the last quarter. Low power presaturation of {sup 129}Xe adsorbed in two coals produces a hole-burning effect in the adsorbed xenon NMR signals, indicating that these signals are broad due to overlap of a series of chemical shifts. Saturation transfer to the entire adsorbed xenon signal and to the extraparticle gas is observed with increasing presaturation time. Differences in timing of saturation transfer to the external gas have implications for the nature of the connectivity of the pore structures in coal.
Date: October 1, 1996
Creator: Anderson, S.A.; Hatcher, P.G. & Radovic, L.R.
Partner: UNT Libraries Government Documents Department

First operation of the upgraded SLAC A-Line

Description: The SLAC A-Line has been upgraded to transport electrons to fixed target experiments in End Station A (ESA) with energies up to 50 GeV. From September through November, 1995, this beam line was commissioned and used to deliver 48.36 GeV polarized electrons to Experiment E-154 at 120 pulses/sec and up to 10{sup 11} e{sup {minus}}/pulse. The beam had a full width momentum spread of less than 0.5 percent, and was focused to a small spot ({sigma}=0.7 mm) at the target. In this paper the authors describe the first operational experience with this new beam line.
Date: October 1, 1996
Creator: Erickson, R.; Anderson, S. & Baker, A.
Partner: UNT Libraries Government Documents Department

Geologic ages and accumulation rates of basalt-flow groups and sedimentary interbeds in selected wells at the Idaho National Engineering Laboratory, Idaho

Description: Geologic ages and accumulation rates, estimated from regressions, were used to evaluate measured ages and interpreted stratigraphic and structural relations of basalt and sediment in the unsaturated zone and the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL) in eastern Idaho. Geologic ages and accumulation rates were estimated from standard linear regressions of 21 mean potassium-argon (K-Ar) ages, selected mean paleomagnetic ages, and cumulative depths of a composite stratigraphic section composed of complete intervals of basalt and sediment that were deposited in areas of past maximum subsidence. Accumulation rates also were estimated from regressions of stratigraphic intervals in three wells in and adjacent to an area of interpreted uplift at and near the Idaho Chemical Processing Plant (ICPP) and the Test Reactor Area (TRA) to allow a comparison of rates in areas of past uplift and subsidence. Estimated geologic ages range from about 200 thousand to 1.8 million years before present and are reasonable approximations for the interval of basalt and sediment above the effective base of the aquifer, based on reported uncertainties of corresponding measured ages. Estimated ages between 200 and 800 thousand years are within the range of reported uncertainties for all 15 K-Ar ages used in regressions and two out of three -argon ({sup 40}Ar/{sup 39}Ar) ages of duplicate argon samples. Two sets of estimated ages between 800 thousand and 1.8 million years are within the range of reported uncertainties for all seven K-Ar ages used in regressions, which include one shared age of about 800 thousand years. Two sets of ages were estimated for this interval because K-Ar ages make up two populations that agree with previous and revised ages of three paleomagnetic subchrons. The youngest set of ages is consistent with a K-Ar age from the effective base of the aquifer that ...
Date: January 1, 1997
Creator: Anderson, S. R.; Liszewski, M. J. & Cecil, L. D.
Partner: UNT Libraries Government Documents Department

Fiber optic sensor: Feedback control design and implementation

Description: Digital feedback control of Gas Tungsten Arc Welding (GTAW) has been demonstrated on a tube sample of stainless steel and titanium alloy. A fiber optic sensor returns a signal proportional to backside radiance from the workpiece; that signal is used by the controller to compute a compensation weld current. The controller executes 10 times a second on an Intel 486 chip. For travel speeds of 3 to 6 inches per minute and thicknesses between 0.025 and 0.10 inches, constant backside bead width was maintained within 0.02 inches, from startup to tie-in.
Date: July 1, 1997
Creator: Tung, D.; Bertram, L.; Hillaire, R.; Anderson, S.; Leonard, S. & Marburger, S.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, October 1996--December 1996

Description: Selective presaturation and saturation transfer {sup 129}Xe NMR experiments were performed on a high volatile C bituminous coal and an anthracite. The experiments detect the movement of xenon atoms among different regions of the internal surface, and to the external surface of the coal particles. The results indicate that adsorbed xenon atoms can move to the external surface of the bituminous coal significantly faster than in the anthracite. The results are interpreted in terms of the porous structure of the coals.
Date: January 1, 1997
Creator: Anderson, S.A.; Hatcher, P.G. & Radovic, L.R.
Partner: UNT Libraries Government Documents Department

SLAC accelerator operations report: 1995--1997

Description: Operational statistics for the linear accelerator programs at SLAC are presented, including run-time records for SLC and the fixed-target programs. Also included are summaries of reliability and maintenance-related statistics.
Date: May 1, 1997
Creator: Erickson, R.; Allen, C.W.; Anderson, S.; Linebarger, W. & Stanek, M.
Partner: UNT Libraries Government Documents Department

Stratigraphy of the unsaturated zone and the Snake River Plain aquifer at and near the Idaho National Engineering Laboratory, Idaho

Description: The unsaturated zone and the Snake River Plain aquifer at and near the Idaho National Engineering Laboratory (INEL) are made up of at least 178 basalt-flow groups, 103 sedimentary interbeds, 6 andesite-flow groups, and 4 rhyolite domes. Stratigraphic units identified in 333 wells in this 890-mile{sup 2} area include 121 basalt-flow groups, 102 sedimentary interbeds, 6 andesite-flow groups, and 1 rhyolite dome. Stratigraphic units were identified and correlated using the data from numerous outcrops and 26 continuous cores and 328 natural-gamma logs available in December 1993. Basalt flows make up about 85% of the volume of deposits underlying the area.
Date: August 1, 1997
Creator: Anderson, S.R. & Liszewski, M.J.
Partner: UNT Libraries Government Documents Department

Taxonomic and developmental aspects of radiosensitivity

Description: Considerable information is available on the effects of radioactivity on adult and early life stages of organisms. The preponderance of data is on mortality after a single irradiation with relatively high doses. Unfortunately, because experiments were carried out under different conditions and for different time periods, the validity of comparing the results from different laxonomic groups is questionable. In general, the conclusions are that there is a relationship (1) between radioresistance to high doses of acute radiation and taxonomy of the organism, primitive forms being more radioresistant than complex vertebrates and (2) between radiosensitivity and developmental stage, early life stages being more sensitive than later stages. The first conclusion may be related to the capability of the organism to repopulate cells and to differentiate and redifferentiate them; the second to the rate of cellular division and to the degree of differentiation. In question, however, is the relevance of the responses from high levels of acute radiation to that of the responses to long-term exposure to low levels of radiation, which are ecologically of more interest. Data from studies of the effects of acute and chronic exposure on development of gametes and zygotes indicate that, for some fishes and invertebrates, responses at the cellular and molecular levels show effect levels comparable to those observed in some mammals. Acute doses between 0,05 and 0.5Cy and dose rates between 0.02 to 0.2mCy/h appear to define critical ranges in which detrimental effects on fertility are first observed in a variety of radiosensitive organisms. To better understand inherent radiosensitivity, we need more information on the ability of cells to repopulate and differentiate and to prevent or repair damage to biological critical molecules, such as DNA, because these factors may alter significantly organisms` responses to radiation.
Date: November 1, 1996
Creator: Harrison, F.L. & Anderson, S.L.
Partner: UNT Libraries Government Documents Department

Opportunistic or event-driven maintenance at the Stanford Linear Accelerator Center

Description: The Stanford Linear Accelerator Center (SLAC) uses a maintenance management philosophy that is best described as opportunistic or event-driven. Opportunistic maintenance can be defined as a systematic method of collecting, investigating, pre-planning, and publishing a set of proposed maintenance tasks and acting on them when there is an unscheduled failure or repair ``opportunity``. Opportunistic maintenance can be thought of as a modification of the run-to-fail maintenance management philosophy. This maintenance plan was adopted and developed to improve the overall availability of SLAC`s linear accelerator, beam delivery systems, and associated controls, power systems, and utilities. In the late 1980`s, as the technical complexity of the accelerator facility increased, variations on a conventional maintenance plan were used with mixed results. These variations typically included some type of regular periodic interruption to operations. The periodic shutdowns and unscheduled failures were additive and resulted in unsatisfactory availability. Maintenance issues are evaluated in a daily meeting that includes the accelerator managers, maintenance supervisors and managers, safety office personnel, program managers, and accelerator operators. Lists of pending maintenance tasks are made available to the general SLAC population by a World Wide Web site on a local internet. A conventional information system which pre-dates the WWW site is still being used to provide paper copies to groups that are not yet integrated into the WWW system. The local internet provides real time maintenance information, allowing people throughout the facility to track progress on tasks with essentially real-time status updates. With the introduction of opportunistic maintenance, the accelerator`s availability has been measurably better. This paper will discuss processes, rolls and responsibilities of key maintenance groups, and management tools developed to support opportunistic maintenance.
Date: March 1, 1997
Creator: Allen, C.W.; Anderson, S.; Erickson, R.; Linebarger, W.; Sheppard, J.C. & Stanek, M.
Partner: UNT Libraries Government Documents Department

The next linear collider damping ring complex

Description: We report progress on the design of the Next Linear Collider (NLC) Damping Rings complexes. The purpose of the damping rings is to provide low emittance electron and positron bunch trains to the NLC linacs, at a rate of 120 Hz. As an option to operate at the higher rate of 180 Hz, two 1.98 GeV main damping rings per beam are proposed, and one positron pre-damping ring. The main damping rings store up to 0.8 amp in 3 trains of 190 bunches each and have normalized extracted beam emittances {gamma}{var_epsilon}x = 3 mm-mrad and {gamma}{var_epsilon}y = 0.02 mm-mrad. The optical designs, based on a theoretical minimum emittance lattice (TME), are described, with an analysis of dynamic aperture and non-linear effects. Key subsystems and components are described, including the wiggler, the vacuum systems and photon stop design, and the higher-order-mode damped RF cavities. Impedance and instabilities are discussed.
Date: June 12, 2001
Creator: Corlett,J.; Atkinson,D.; De Santis,S.; Hartman, N.; Kennedy, K.; Li, D. et al.
Partner: UNT Libraries Government Documents Department

Geologic Controls of Hydraulic Conductivity in the Snake River Plain Aquifer At and Near the Idaho National Engineering and Environmental Laboratory, Idaho

Description: The effective hydraulic conductivity of basalt and interbedded sediment that compose the Snake River Plain aquifer at and near the Idaho National Engineering and Environmental Laboratory (INEEL) ranges from about 1.0x10 -2 to 3.2x10 4 feet per day (ft/d). This six-order-of-magnitude range of hydraulic conductivity was estimated from single-well aquifer tests in 114 wells, and is attributed mainly to the physical characteristics and distribution of basalt flows and dikes. Hydraulic conductivity is greatest in thin pahoehoe flows and near-vent volcanic deposits. Hydraulic conductivity is least in flows and deposits cut by dikes. Estimates of hydraulic conductivity at and near the INEEL are similar to those measured in similar volcanic settings in Hawaii. The largest variety of rock types and the greatest range of hydraulic conductivity are in volcanic rift zones, which are characterized by numerous aligned volcanic vents and fissures related to underlying dikes. Three broad categories of hydraulic conductivity corresponding to six general types of geologic controls can be inferred from the distribution of wells and vent corridors. Hydraulic conductivity of basalt flows probably is increased by localized fissures and coarse mixtures of interbedded sediment, scoria, and basalt rubble. Hydraulic conductivity of basalt flows is decreased locally by abundant alteration minerals of probable hydrothermal origin. Hydraulic conductivity varies as much as six orders of magnitude in a single vent corridor and varies from three to five orders of magnitude within distances of 500 to 1,000 feet. Abrupt changes in hydraulic conductivity over short distances suggest the presence of preferential pathways and local barriers that may greatly affect the movement of ground water and the dispersion of radioactive and chemical wastes downgradient from points of waste disposal.
Date: February 1, 1999
Creator: Anderson, S. R.; Kuntz, M. A. & Davis, L. C.
Partner: UNT Libraries Government Documents Department

Very High Resolution Simulation of Compressible Turbulence on the IBM-SP System

Description: Understanding turbulence and mix in compressible flows is of fundamental importance to real-world applications such as chemical combustion and supernova evolution. The ability to run in three dimensions and at very high resolution is required for the simulation to accurately represent the interaction of the various length scales, and consequently, the reactivity of the intermixing species. Toward this end, we have carried out a very high resolution (over 8 billion zones) 3-D simulation of the Richtmyer-Meshkov instability and turbulent mixing on the IBM Sustained Stewardship TeraOp (SST) system, developed under the auspices of the Department of Energy (DOE) Accelerated Strategic Computing Initiative (ASCI) and located at Lawrence Livermore National Laboratory. We have also undertaken an even higher resolution proof-of-principle calculation (over 24 billion zones) on 5832 processors of the IBM, which executed for over an hour at a sustained rate of 1.05 Tflop/s, as well as a short calculation with a modified algorithm that achieved a sustained rate of 1.18 Tflop/s. The full production scientific simulation, using a further modified algorithm, ran for 27,000 timesteps in slightly over a week of n-all time using 3840 processors of the IBM system, clocking a sustained throughput of roughly 0.6 teraflop per second. Nearly 300,000 graphics files comprising over three terabytes of data were produced and post-processed. The capability of running in 3-D at high resolution enabled us to get a more accurate and detailed picture of the fluid-flow structure--in particular, to simulate the development of fine scale structures from the interactions of long- and short-wavelength phenomena, to elucidate differences between two-dimensional and three-dimensional turbulence, to explore a conjecture regarding the transition from unstable flow to fully developed turbulence with increasing Reynolds number, and to ascertain convergence of the computed solution with respect to mesh resolution.
Date: August 5, 1999
Creator: Mirin, A.A.; Cohen, R.H.; Curtis, B.C.; Dannevik, W.P.; Dimits, A.M.; Duchaineau, M.A. et al.
Partner: UNT Libraries Government Documents Department

Photoionization of (H2)2 and the Clusters of O2 Molecules

Description: Photoionizationof (H{sub 2}){sub 2} and clusters of O{sub 2} are investigated in a molecular beam experiment. No evidence was found for the existence of stable (H{sub 2}){sub 2}{sup +}. Photoionization spectra of (H{sub 2}){sub 2}+h{nu}{yields} {yields} H{sub 3}{sup +} + H + e is quite similar to that of H{sup 2} +h{nu} {yields} H{sub 2}{sup +} + e, yet the appreciable differences in some features of spectra suggests that there is a competition between the autoionization and vibrational predissociation of vibronically excited (H{sub 2}){sub 2}. From the photoionization thresholds of (O{sub 2}){sub n}, n = 1-5, it is concluded that (O{sub 2}){sub 2}{sup +} is bound by 0.26 ± 0.02 eV, but the additional binding energies for higher clusters of O{sub 2}{sup +} are much smaller; just about what one would expect from a charge induced dipole interaction.
Date: June 1, 1980
Creator: Anderson, S. L.; Hirooka, T.; Tiedemann, P. W.; Mahan, B. H. & Lee, Y. T.
Partner: UNT Libraries Government Documents Department

An X-Band Gun Test Area at SLAC

Description: The X-Band Test Area (XTA) is being assembled in the NLCTA tunnel at SLAC to serve as a test facility for new RF guns. The first gun to be tested will be an upgraded version of the 5.6 cell, 200 MV/m peak field X-band gun designed at SLAC in 2003 for the Compton Scattering experiment run in ASTA. This new version includes some features implemented in 2006 on the LCLS gun such as racetrack couplers, increased mode separation and elliptical irises. These upgrades were developed in collaboration with LLNL since the same gun will be used in an injector for a LLNL Gamma-ray Source. Our beamline includes an X-band acceleration section which takes the electron beam up to 100 MeV and an electron beam measurement station. Other X-Band guns such as the UCLA Hybrid gun will be characterized at our facility.
Date: September 7, 2012
Creator: Limborg-Deprey, C.; Adolphsen, C.; Chu, T.S.; Dunning, M.P.; Jobe, R.K.; Jongewaard, E.N. et al.
Partner: UNT Libraries Government Documents Department