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Active Control of 2/1 Magnetic Islands in the HBT-EP Tokamak (open access)

Active Control of 2/1 Magnetic Islands in the HBT-EP Tokamak

Closed and open loop control techniques were applied to growing m/n=2/1 rotating islands in wall stabilized plasmas in the HBT-EP tokamak. The approach taken by HBT-EP combines an adjustable segmented conducting wall (which slows the growth or stabilizes ideal external kinks) with a number of small (6{degree} wide) saddle coils located between the gaps of the conducting wall. In this paper we report demonstration of 2-phase island rotation control from 5 kHz to 15 kHz and observation of the phase instability which are well modeled by the single-helicity, predictions of nonlinear Rutherford island dynamics for 2/1 tearing modes including important effects of ion inertia and FLR which appears as a damping term in the model equations. The closed loop response of active feedback control of the 2/1 mode at moderate gain was observed to be in good agreement with the theory. We have also demonstrated suppression of the 2/1 island growth using an asynchronous frequency modulation drive which maintains the flow damping of the island by application of rotating control fields with frequencies alternating above and below the natural mode frequency. This frequency modulation control technique was also able to prevent disruptions normally observed to follow giant sawtooth crashes in …
Date: November 18, 1997
Creator: Navratil, G. A.; Cates, C.; Mauel, M. E.; Maurer, D.; Nadle, D.; Taylor, E. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 98, No. 207, Ed. 1 Tuesday, November 18, 1997 (open access)

Altus Times (Altus, Okla.), Vol. 98, No. 207, Ed. 1 Tuesday, November 18, 1997

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analysis of tritium mission FMEF/FAA fuel handling accidents (open access)

Analysis of tritium mission FMEF/FAA fuel handling accidents

The Fuels Material Examination Facility/Fuel Assembly Area is proposed to be used for fabrication of mixed oxide fuel to support the Fast Flux Test Facility (FFTF) tritium/medical isotope mission. The plutonium isotope mix for the new mission is different than that analyzed in the FMEF safety analysis report. A reanalysis was performed of three representative accidents for the revised plutonium mix to determine the impact on the safety analysis. Current versions computer codes and meterology data files were used for the analysis. The revised accidents were a criticality, an explosion in a glovebox, and a tornado. The analysis concluded that risk guidelines were met with the revised plutonium mix.
Date: November 18, 1997
Creator: Van Keuren, J. C.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 76, No. 15, Ed. 1 Tuesday, November 18, 1997 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 76, No. 15, Ed. 1 Tuesday, November 18, 1997

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 93, No. 92, Ed. 1 Tuesday, November 18, 1997 (open access)

The Boerne Star (Boerne, Tex.), Vol. 93, No. 92, Ed. 1 Tuesday, November 18, 1997

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: Aldridge, Leon
Object Type: Newspaper
System: The Portal to Texas History
CASES-97 : Diurnal variation of the fair-weather PBL. (open access)

CASES-97 : Diurnal variation of the fair-weather PBL.

The CASES-97 dataset, supplemented by data from the surrounding area and from satellite, will enable us to isolate the effects of soil moisture on boundary layer evolution.Our initial approach will be to use the integrated dataset to determine (a) the factors that contribute to PBL growth, and (b) the factors that determine the wind, temperature, and wind profiles in the growing PBL. This process will help us to consolidate the dataset and tease out remaining inconsistencies. As soon as reasonable, we want to use the dataset in mesoscale numerical models, to test and refine our conclusions. Further detail on the CASES-97 field program can be found at the World Wide Web site at: http://www.mmm.ucar.edu/cases/cases.html.
Date: November 18, 1997
Creator: Coulter, R. L.; Grossman, R. L.; Hicks, B.; Horst, T.; Klazura, G.; LeMone, M. A. et al.
Object Type: Article
System: The UNT Digital Library
Chickasha Daily Express (Chickasha, Okla.), Ed. 1 Tuesday, November 18, 1997 (open access)

Chickasha Daily Express (Chickasha, Okla.), Ed. 1 Tuesday, November 18, 1997

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Daily Chickasha Star (Chickasha, Okla.), Vol. 96, No. 140, Ed. 1 Tuesday, November 18, 1997 (open access)

The Daily Chickasha Star (Chickasha, Okla.), Vol. 96, No. 140, Ed. 1 Tuesday, November 18, 1997

Newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: Settle, David
Object Type: Newspaper
System: The Gateway to Oklahoma History
Deuteron photodisintegration : new results from TJNAF. (open access)

Deuteron photodisintegration : new results from TJNAF.

The first measurements of the differential cross section from d({gamma},p)n up to 4.0 GeV were performed at the Thomas Jefferson National Accelerator Facility (TJNAF, formerly CEBAF). Bremsstrahlung photons from electron beam impinging on a copper radiator and a liquid deuterium target were employed for this experiment. The experiment was performed in Hall C where the photoprotons at forward angles in the center-of-mass were detected in the High Momentum Spectrometer (HMS) and photoprotons at backward angles were detected in the Short Orbit Spectrometer (SOS). The bremsstrahlung photon energy was reconstructed from the measured proton momentum and angle using the two-body kinematics. We report the cross section results at the proton center-of-mass angles of 37{degree} and 90{degree}. These results are in good agreement with previous lower energy measurements. The 90{degree} data continue to show the constituent-counting-rule behavior up to 4 GeV. The results will be compared with models based on QCD as well as those based on meson-exchange theory.
Date: November 18, 1997
Creator: Abbott, D. J.; Ahmidouch, A.; Armstrong, C. S.; Arrington, J.; Cummings, W. J.; Geesaman, D. F. et al.
Object Type: Article
System: The UNT Digital Library
Empirical evaluation of the radiative cooling coefficient for krypton gas in the FTU plasma (open access)

Empirical evaluation of the radiative cooling coefficient for krypton gas in the FTU plasma

For future fusion reactors, a careful balance must be achieved between the cooling of the outer plasma via impurity radiation and the deleterious effects of inevitable core penetration by impurity ions. We have injected krypton gas into the Frascati Tokamak Upgrade (FTU) plasma. The measured visible bremsstrahlung and bolometric signals from krypton have been inverted and the resulting radial impurity density profile and power loss profile for krypton gas are extracted. Using the measured electron density and temperature profiles, the radiative cooling coefficient for krypton is derived. The level of intrinsic impurities (Mo, Cr, Mn and Fe) in the plasma during the krypton puffing is monitored with a VUV SPRED spectrometer. Models for krypton emissivity from the literature are compared to our measured results. 7 figs.
Date: November 18, 1997
Creator: Fournier, K.B.; Pacella, D.; Gregory, B.C.; May, M.J.; Mazzitelli, G.; Gabellieri, L. et al.
Object Type: Report
System: The UNT Digital Library
Enduring Nuclear Fuel Cycle, Proceedings of a panel discussion (open access)

Enduring Nuclear Fuel Cycle, Proceedings of a panel discussion

The panel reviewed the complete nuclear fuel cycle in the context of alternate energy resources, energy need projections, effects on the environment, susceptibility of nuclear materials to theft, diversion, and weapon proliferation. We also looked at ethical considerations of energy use, as well as waste, and its effects. The scope of the review extended to the end of the next century with due regard for world populations beyond that period. The intent was to take a long- range view and to project, not forecast, the future based on ethical rationales, and to avoid, as often happens, long-range discussions that quickly zoom in on only the next few decades. A specific nuclear fuel cycle technology that could satisfy these considerations was described and can be applied globally.
Date: November 18, 1997
Creator: Walter, C. E., LLNL
Object Type: Article
System: The UNT Digital Library
EPICS : Extensible record and device support. (open access)

EPICS : Extensible record and device support.

Although the design of extensible support was not intentionally object oriented, the design does have an object-oriented flavor. Here we discuss the good and bad aspects of using object-oriented ideas. Since the structures generated from a Record Description File contain only data and not methods, they are not similar to Java or C++ classes. Because methods are not present, a clear separation between static and run-time database access is possible. This is a good feature and should be kept. It also allows generation of C structures that can be used by either C or C++ code. The record and device support entry tables are almost like Java interfaces or pure abstract C++ classes. We can state that EPICS databases are defined via a Database Definition Language and an Abstract Interface Definition. The two main shortcomings of the existing implementation are (1) only two interfaces are defined RSETS and DSETS (actually a third called a driver entry table is also defined), and (2) the way hardware links are implemented makes it extremely difficult to support arbitrary bus types and additional hardware configuration information.
Date: November 18, 1997
Creator: Dalesio, L. R. & Kraimer, M. R.
Object Type: Article
System: The UNT Digital Library
Estimation of mass transfer and kinetics in operating biofilters for removal of VOCs (open access)

Estimation of mass transfer and kinetics in operating biofilters for removal of VOCs

Long-term, stable operation of trickle-bed bioreactors remains desirable, but is difficult to achieve for industrial processes, which generate continuous streams of dilute gaseous hydrocarbons. Mass transfer and kinetic parameters are difficult to measure, complicating predictive estimates. Two methods are presented which were used to predict the importance of mass transfer versus kinetics limitations in operating trickle-bed biofilters. Both methods altered the overall kinetic activity of the biofilter and estimated the effective mass transfer coefficient (K{sub 1}a) by varying the VOC (volatile organic contaminant) loading rate and concentration. The first method, used with developing biofilters possessing low biomass, involved addition of cultured biomass to the recirculating liquid to effect an overall change in VOC removal capacity. The second method altered the total bed temperature of a well-established biofilter to effect a change. Results and modeling from these experiments are presented for a mixed culture biofilter which is capable of consuming sparingly soluble alkanes, such as pentane and isobutane. Methods to control overgrowth are discussed which were used to operate one reactor continuously for over 24 months with sustained degradation of VOC alkanes with a rate of 50 g/h/m{sup 3}.
Date: November 18, 1997
Creator: Barton, J. W.; Davison, B. H. & Gable, C. C.
Object Type: Article
System: The UNT Digital Library
FY1998 USDA Budget and Appropriations: Domestic Food Programs (open access)

FY1998 USDA Budget and Appropriations: Domestic Food Programs

None
Date: November 18, 1997
Creator: Jones, Jean Yavis
Object Type: Report
System: The UNT Digital Library
FY1998 USDA Budget and Appropriations: Domestic Food Programs (open access)

FY1998 USDA Budget and Appropriations: Domestic Food Programs

None
Date: November 18, 1997
Creator: Jones, Jean Yavis
Object Type: Report
System: The UNT Digital Library
Geometric Summary of the 9 Chip Ladder for the D0 Silicon Tracker (open access)

Geometric Summary of the 9 Chip Ladder for the D0 Silicon Tracker

Two hybrids types are required to accomodate the flipping of ladders within each bulkhead layer, in order to account for the pigtail routing. Left and right versions are shown below, following the definitions laid out by Mike Matulik. These drawings are not to proper scale in the sketches below. The dimensionally correct versions of the 9 chip hybrids are stored in DCS under drawing number 3823.112-MD-317803 for the lefthanded version, and 3823.112-MD-317804 for the right handed version. Handedness of the hybrids are designated as shown in the figures and table below. There are long and short versions of both the left and the right, for four total 9 chip hdi designs. The pigtail lengths of the long and short are shown in a table in the hybrid drawings which reside in DCS. The chamfer in the hybrid corners (N side) is placed in order to enable the hybrid to be glued to the beryllium substrate, whereas the rectangular cuttout on the same side is to allow direct gluing of a temperature sensor to the substrate metal. The oblong shape on the N side of both hybrids is a 'stay-clear' region (defined in the final drawings) where pressure will be applied …
Date: November 18, 1997
Creator: Ratzmann, P.; Cooper, W.; Goloskie, D.; Kowalski, J.; Lipton, R.; Rapidis, P. et al.
Object Type: Report
System: The UNT Digital Library
The Harper Herald (Harper, Tex.), Vol. 69, No. 45, Ed. 1 Tuesday, November 18, 1997 (open access)

The Harper Herald (Harper, Tex.), Vol. 69, No. 45, Ed. 1 Tuesday, November 18, 1997

Weekly newspaper from Harper, Texas that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: Bishop, Karen
Object Type: Newspaper
System: The Portal to Texas History
Leptonic and semileptonic decays of heavy mesons. (open access)

Leptonic and semileptonic decays of heavy mesons.

None
Date: November 18, 1997
Creator: Ivanov, M. A.; Kalinovsky, Y. L.; Maris, P. & Roberts, C. D.
Object Type: Article
System: The UNT Digital Library
[Letter to Dan Morales from John Anzalone concerning statewide poll results] (open access)

[Letter to Dan Morales from John Anzalone concerning statewide poll results]

Letter from John Anzalone to Dan Morales about the results of a statewide poll on Morales.
Date: November 18, 1997
Creator: Anzalone, John
Object Type: Letter
System: The UNT Digital Library
The Mannford Star (Mannford, Okla.), Vol. 2, No. 117, Ed. 1 Tuesday, November 18, 1997 (open access)

The Mannford Star (Mannford, Okla.), Vol. 2, No. 117, Ed. 1 Tuesday, November 18, 1997

Weekly newspaper from Mannford, Oklahoma that includes local, state, and national news along with advertising.
Date: November 18, 1997
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
Modeling forces in high-temperature superconductors (open access)

Modeling forces in high-temperature superconductors

We have developed a simple model that uses computed shielding currents to determine the forces acting on a high-temperature superconductor (HTS). The model has been applied to measurements of the force between HTS and permanent magnets (PM). Results show the expected hysteretic variation of force as the HTS moves first toward and then away from a permanent magnet, including the reversal of the sign of the force. Optimization of the shielding currents is carried out through a simulated annealing algorithm in a C++ program that repeatedly calls a commercial electromagnetic software code. Agreement with measured forces is encouraging.
Date: November 18, 1997
Creator: Turner, L. R. & Foster, M. W.
Object Type: Article
System: The UNT Digital Library
Neutron scattering characterization of pure and rare-earth modified zirconia catalysis. (open access)

Neutron scattering characterization of pure and rare-earth modified zirconia catalysis.

The combined application of neutron powder diffraction, small angle neutron scattering and neutron inelastic scattering has led to improved understanding of the crystal phases, defect structure, microstructure and hydroxyl/water dynamics in pure and lanthanide-modified zirconia catalysts. Powder diffraction experiments quantified the degree of stabilization and provided evidence for static, oxygen vacancy-induced atomic displacements in stabilized zirconia. Quantitative assessment of Bragg peak breadths led to measurements of ''grain size'', representing coherency length of long-range ordered atomic arrangements (crystals). Small angle neutron scattering provided a separate measurement of ''grain size'', representing the average size of the primary particles in the aggregates, and the evolution of porosity (micro- versus meso-) and surface roughness caused by RE modification and heat treatment. Finally, the dynamics of hydrogen atoms associated with surface hydroxyls and adsorbed water was investigated by neutron-inelastic scattering, revealing changes in frequency and band breadth of O-H stretch, H-O-H bend, and librational motion of water molecules.
Date: November 18, 1997
Creator: Loong, C.-K.; Ozawa, M.; Richardson, J. W., Jr.; Suzuki, S. & Thiyagarajan, P.
Object Type: Article
System: The UNT Digital Library
[News Clip: Auto strike] captions transcript

[News Clip: Auto strike]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: November 18, 1997, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Meg Ryan] captions transcript

[News Clip: Meg Ryan]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: November 18, 1997, 11:00 a.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library